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Sample records for invasive mechanical ventilation

  1. Patient-ventilator dyssynchrony during assisted invasive mechanical ventilation.

    PubMed

    Murias, G; Villagra, A; Blanch, L

    2013-04-01

    Patient-ventilator dyssynchrony is common during mechanical ventilation. Dyssynchrony decreases comfort, prolongs mechanical ventilation and intensive care unit stays, and might lead to worse outcome. Dyssynchrony can occur during the triggering of the ventilator, the inspiration period after triggering, the transition from inspiration to expiration, and the expiratory phase. The most common dyssynchronies are delayed triggering, autotriggering, ineffective inspiratory efforts (which can occur at any point in the respiratory cycle), mismatch between the patient's and ventilator's inspiratory times, and double triggering. At present, the detection of dyssynchronies usually depends on healthcare staff observing ventilator waveforms; however, performance is suboptimal and many events go undetected. To date, technological complexity has made it impossible to evaluate patient-ventilator synchrony throughout the course of mechanical ventilation. Studies have shown that a high index of dyssynchrony may increase the duration of mechanical ventilation. Better training, better ventilatory modes, and/or computerized systems that permit better synchronization of patients' demands and ventilator outputs are necessary to improve patient-ventilator synchrony.

  2. Modern non-invasive mechanical ventilation turns 25.

    PubMed

    Díaz Lobato, Salvador; Mayoralas Alises, Sagrario

    2013-11-01

    The history of non-invasive mechanical ventilation goes back more than 100 years, but it was not until 1987 when what we could call "modern" non-invasive mechanical ventilation was developed. The description of Delaubier and Rideau of a patient with Duchenne's disease who had been effectively ventilated through a nasal mask marked the start of a new era in the history of non-invasive mechanical ventilation. Over these last 25years, we have witnessed exponential growth in its use, field of activity and technological advances on an exciting fast-paced track. We believe that it is time to review the main milestones that have marked the development of non-invasive mechanical ventilation to date, while paying homage to this therapeutic method that has contributed so much to the advancement of respiratory medicine in the last 25years.

  3. [Home mechanical ventilation: Invasive and noninvasive ventilation therapy for chronic respiratory failure].

    PubMed

    Huttmann, S E; Storre, J H; Windisch, W

    2015-06-01

    Home mechanical ventilation represents a valuable therapeutic option to improve alveolar ventilation in patients with chronic respiratory failure. For this purpose both invasive ventilation via tracheostomy and noninvasive ventilation via facemasks are available. The primary goal of home mechanical ventilation is a reduction of symptoms, improvement of quality of life and in many cases reduction of mortality. Elective establishment of home mechanical ventilation is typically provided for noninvasive ventilation in respect to clinical symptoms and partial pressure of carbon dioxide depending on the underlying disease. However, invasive mechanical ventilation is increasingly being used to continue ventilatory support in polymorbid patients following unsuccessful weaning. Recommendations and guidelines have been published by the German Respiratory Society (DGP).

  4. Quality of life of ALS and LIS patients with and without invasive mechanical ventilation.

    PubMed

    Rousseau, Marie-Christine; Pietra, Stéphane; Blaya, José; Catala, Anne

    2011-10-01

    There are very few studies where quality of life (QOL) is assessed in patients with complete physical and functional disability and dependence to invasive mechanical ventilation (IV). We compared QOL of amyotrophic lateral sclerosis (ALS) and locked-in-syndrome (LIS) patients with invasive mechanical ventilation to ALS and LIS patients without mechanical invasive ventilation. Thirty-four patients, 27 with ALS and seven with LIS (vascular or tumoral aetiology) were included in the study. Twelve had invasive ventilation, 22 had non-invasive ventilation, and in the non-invasive ventilation group, five of them had ventilation via mask. The following scales were used for patients: ALS Functional Rating Scale (ALSFRS), McGILL, Short-Form 36 (SF36), Beck Depression Inventory-II, the Toronto Alexithymia Scale and the anxiety inventory of Spielberger. Mean ALSFRS scores were significantly lower in the invasive ventilation group (IV) than in the non-invasive ventilation group. McGILL and SF36 were not significantly different between the IV group and the non-invasive ventilation group; there were no significant differences between the two groups for others scales either. Comparison between IV group and LIS without invasive mechanical ventilation revealed no significant difference for SF36 and McGILL QOL scores. QOL was not significantly different between the IV and not invasively ventilated patients, but ALSFRS was significantly lower in the IV group, and comparison of QOL scores between non-ventilated LIS patients who had the same score of dependence that invasively ventilated patients did not show any difference. Invasive mechanical ventilation for patients who accept tracheotomy allows life prolongation and their QOL is not affected; medical teams should be aware of that.

  5. [Non-invasive mechanical ventilation in the pre- and intraoperative period and difficult airway].

    PubMed

    Esquinas, A M; Jover, J L; Úbeda, A; Belda, F J

    2015-11-01

    Non-invasive mechanical ventilation is a method of ventilatory assistance aimed at increasing alveolar ventilation, thus achieving, in selected subjects, the avoidance of endotracheal intubation and invasive mechanical ventilation, with the consequent improvement in survival. There has been a systematic review and study of the technical, clinical experiences, and recommendations concerning the application of non-invasive mechanical ventilation in the pre- and intraoperative period. The use of prophylactic non-invasive mechanical ventilation before surgery that involves significant alterations in the ventilatory function may decrease the incidence of postoperative respiratory complications. Its intraoperative use will mainly depend on the type of surgery, type of anaesthetic technique, and the clinical status of the patient. Its use allows greater anaesthetic depth without deterioration of oxygenation and ventilation of patients.

  6. Pressure versus volume controlled modes in invasive mechanical ventilation.

    PubMed

    Garnero, A J; Abbona, H; Gordo-Vidal, F; Hermosa-Gelbard, C

    2013-05-01

    The first generation of mechanical ventilators were controlled and cycled by pressure. Unfortunately, they did not allow control of the delivered tidal volume under changes in the dynamics of the respiratory system. This led to a second generation of ventilators that allowed volume control, hence favoring the ventilatory strategy based on normalization of the arterial gases. Studies conducted in the 1980s which related lung injury to the high ventilator pressures utilized while treating acute respiratory distress syndrome patients renewed interest in pressure-controlled mechanical ventilation. In addition, new evidence became available, leading to the development of pulmonary protective strategies aiming at preventing the progression of ventilator-induced lung injury. This review provides a detailed description of the control of pressure or volume using certain ventilatory modes, and offers a general view of their advantages and disadvantages, based on the latest available evidence.

  7. [Non-invasive mechanical ventilation in the treatment of acute heart failure].

    PubMed

    Alfonso Megido, Joaquín; González Franco, Alvaro

    2014-03-01

    When acute heart failure progresses and there is acute cardiogenic pulmonary edema, routine therapeutic measures should be accompanied by other measures that help to correct oxygenation of the patient. The final and most drastic step is mechanical ventilation. Non-invasive ventilation has been developed in the last few years as a method that attempts to improve oxygenation without the need for intubation, thus, in theory, reducing morbidity and mortality in these patients. The present article describes the controversies surrounding the results of this technique and discusses its indications. The article also discusses how to start non-invasive ventilation in patients with acute pulmonary edema from a practical point of view.

  8. Resolution of obstructive atelectasis with non-invasive mechanical ventilation.

    PubMed

    Mirambeaux Villalona, Rosa; Mayoralas Alises, Sagrario; Díaz Lobato, Salvador

    2014-10-01

    Bronchoscopy is a commonly used technique in patients with atelectasis due to mucus plugs. We present here the case of an 82-year-old patient with a history of Meige's syndrome who developed acute respiratory failure due to atelectasis of the right upper lobe associated with hospital-acquired pneumonia. The patient had a severely reduced level of consciousness, significant work-of-breathing and severe hypercapnic acidosis, all of which contraindicated bronchoscopy. Bi-level noninvasive mechanical ventilation (NIMV) was initiated by way of a face mask. Progress was favourable, with clear clinical and gasometric improvement. The chest X-ray performed 12hours later showed complete resolution of the atelectasis. These data suggest that NIMV may be useful in the treatment of atelectasis is some critical patients.

  9. Online estimation of respiratory mechanics in non-invasive pressure support ventilation: a bench model study.

    PubMed

    Mulqueeny, Qestra; Tassaux, Didier; Vignaux, Laurence; Jolliet, Philippe; Schindhelm, Klaus; Redmond, Stephen; Lovell, Nigel H

    2010-01-01

    An online algorithm for determining respiratory mechanics in patients using non-invasive ventilation (NIV) in pressure support mode was developed and embedded in a ventilator system. Based on multiple linear regression (MLR) of respiratory data, the algorithm was tested on a patient bench model under conditions with and without leak and simulating a variety of mechanics. Bland-Altman analysis indicates reliable measures of compliance across the clinical range of interest (± 11-18% limits of agreement). Resistance measures showed large quantitative errors (30-50%), however, it was still possible to qualitatively distinguish between normal and obstructive resistances. This outcome provides clinically significant information for ventilator titration and patient management.

  10. [Non-invasive mechanical ventilation in postoperative patients. A clinical review].

    PubMed

    Esquinas, A M; Jover, J L; Úbeda, A; Belda, F J

    2015-11-01

    Non-invasive ventilation (NIV) is a method of ventilatory support that is increasing in importance day by day in the management of postoperative respiratory failure. Its role in the prevention and treatment of atelectasis is particularly important in the in the period after thoracic and abdominal surgeries. Similarly, in the transplanted patient, NIV can shorten the time of invasive mechanical ventilation, reducing the risk of infectious complications in these high-risk patients. It has been performed A systematic review of the literature has been performed, including examining the technical, clinical experiences and recommendations concerning the application of NIV in the postoperative period.

  11. Non-invasive mechanical ventilation in the treatment of acute respiratory failure in chronic obstructive pulmonary disease.

    PubMed

    Ambrosino, N; Nava, S; Rubini, F

    1993-01-01

    Acute respiratory failure is usually managed by means of mechanical ventilation via an endotracheal tube or tracheostomy, when conservative treatment fails. Invasive mechanical ventilation is associated with several complications. The recent development of non-invasive methods of ventilation, has led to an attempt to avoid the complications of invasive mechanical ventilation during episodes of acute respiratory failure, ensuring at the same time a similar degree of efficacy. Both intermittent negative pressure ventilation and positive pressure ventilation by face or nasal mask have recently been used for this purpose. Negative pressure ventilation by means of iron lung, cuirass or poncho-wrap ventilators, has never been used in place of endotracheal intubation, and studies of this kind of ventilation are inconclusive: as a consequence, there is, at the moment, no indication for the generalized use of negative pressure ventilation in acute respiratory failure. Intermittent positive pressure ventilation by facial or nasal masks, has recently been used in the treatment of respiratory failure in place of endotracheal intubation. The results are promising, but remain controversial. It may be attempted in selected patients with obstructive respiratory disorders, but the procedure is very time-consuming for nurses.

  12. [Mechanical ventilator].

    PubMed

    Kimura, Akio; Hashimoto, S

    2009-07-01

    The development of the computer technology brought reform in the field of medical equipment. Originally the mechanical ventilator was an instrument only as for running by pressure and the tool that let you breathe. However, it has a function to assist a measurement (tidal volume, peek pressure, etc.) and to wean from a ventilator. There is a case to use a mechanical ventilator for after a chest surgical operation. After the operation without the complication, it seems that there is not the special administration. However, special respiratory management is necessary in case of chronic respiratory failure and acute lung injury, acute respiratory distress syndrome. Therefore I introduce a method to use a respirator after an operation in our institution.

  13. [Amyotrophic neuralgia associated with bilateral phrenic paralysis treated with non-invasive mechanical ventilation].

    PubMed

    García García, María Del Carmen; Hernández Borge, Jacinto; Antona Rodríguez, María José; Pires Gonçalves, Pedro; García García, Gema

    2015-09-07

    Amyotrophic neuralgia is an uncommon neuropathy characterized by severe unilateral shoulder pain. Isolated or concomitant involvement of other peripheral motor nerves depending on the brachial plexus such as phrenic or laryngeal nerves is unusual(1). Its etiology is unknown, yet several explanatory factors have been proposed. Phrenic nerve involvement, either unilateral or bilateral, is exceedingly rare. Diagnosis relies on anamnesis, functional and imaging investigations and electromyogram. We report the case of a 48-year-old woman with a past history of renal transplantation due to proliferative glomerulonephritis with subsequent transplant rejection, who was eventually diagnosed with amyotrophic neuralgia with bilateral phrenic involvement, and who required sustained non-invasive mechanical ventilation.

  14. Incidence and causes of non-invasive mechanical ventilation failure after initial success

    PubMed Central

    Moretti, M.; Cilione, C.; Tampieri, A.; Fracchia, C.; Marchioni, A.; Nava, S.

    2000-01-01

    BACKGROUND—The rate of failure of non-invasive mechanical ventilation (NIMV) in patients with chronic obstructive pulmonary disease (COPD) with acute respiratory insufficiency ranges from 5% to 40%. Most of the studies report an incidence of "late failure" (after >48 hours of NIMV) of about 10-20%. The recognition of this subset of patients is critical because prolonged application of NIMV may unduly delay the time of intubation.
METHODS—In this multicentre study the primary aims were to assess the rate of "late NIMV failure" and possible associated predictive factors; secondary aims of the study were evaluation of the best ventilatory strategy in this subset of patients and their outcomes in and out of hospital. The study was performed in two respiratory intensive care units (ICUs) on patients with COPD admitted with an episode of hypercapnic respiratory failure (mean (SD) pH 7.23(0.07), PaCO2 85.3 (15.8) mm Hg).
RESULTS—One hundred and thirty seven patients initially responded to NIMV in terms of objective (arterial blood gas tensions) and subjective improvement. After 8.4 (2.8) days of NIMV 31 patients (23%; 95% confidence interval (CI) 18 to 33) experienced a new episode of acute respiratory failure while still ventilated. The occurrence of "late NIMV failure" was significantly associated with functional limitations (ADL scale) before admission to the respiratory ICU, the presence of medical complications (particularly hyperglycaemia), and a lower pH on admission. Depending on their willingness or not to be intubated, the patients received invasive ventilation (n=19) or "more aggressive" (more hours/day) NIMV (n=12). Eleven (92%) of those in this latter subgroup died while in the respiratory ICU compared with 10 (53%) of the patients receiving invasive ventilation. The overall 90 day mortality was 21% and, after discharge from hospital, was similar in the "late NIMV failure" group and in patients who did not experience a second episode of acute

  15. Respiratory mechanics in COPD patients who failed non-invasive ventilation: role of intrinsic PEEP.

    PubMed

    Antonaglia, Vittorio; Ferluga, Massimo; Capitanio, Guido; Lucangelo, Umberto; Piller, Fulvia; Roman-Pognuz, Erik; Biancardi, Bruno; Caggegi, Giuseppe Davide; Zin, Walter A

    2012-10-15

    Non-invasive positive pressure ventilation (NPPV) is the first choice to treat exacerbations in COPD patients. NPPV can fail owing to different causes related to gas exchange impairment (RF group) or intolerance (INT group). To assess if the respiratory mechanical properties and the ratio between the dynamic and static intrinsic positive end-expiratory pressure (PEEP(i),dyn/PEEP(i),stat), reflecting lung mechanical inequalities, were different between groups, 29 COPD patients who failed NPPV (15 RF and 14 INT) were studied, early after the application of invasive ventilation. Blood gas analysis, clinical status, and mechanical properties were measured. pH was higher in INT patients before intubation (p<0.001). PEEP(i),dyn/PEEP(i),stat was found higher in INT group with (p=0.021) and without PEEP (ZEEP, p<0.01). PEEP(i),dyn/PEEP(i),stat was exponentially associated with the duration of NPPV in INT group (p=0.011). INT and RF patients had similar impairment of respiratory system resistance and elastance.

  16. Pathophysiological Basis of Acute Respiratory Failure on Non-Invasive Mechanical Ventilation.

    PubMed

    Romero-Dapueto, C; Budini, H; Cerpa, F; Caceres, D; Hidalgo, V; Gutiérrez, T; Keymer, J; Pérez, R; Molina, J; Giugliano-Jaramillo, C

    2015-01-01

    Noninvasive mechanical ventilation (NIMV) was created for patients who needed noninvasive ventilator support, this procedure decreases the complications associated with the use of endotracheal intubation (ETT). The application of NIMV has acquired major relevance in the last few years in the management of acute respiratory failure (ARF), in patients with hypoxemic and hypercapnic failure. The main advantage of NIMV as compared to invasive mechanical ventilation (IMV) is that it can be used earlier outside intensive care units (ICUs). The evidence strongly supports its use in patients with COPD exacerbation, support in weaning process in chronic obstructive pulmonary disease (COPD) patients, patients with acute cardiogenic pulmonary edema (ACPE), and Immunosuppressed patients. On the other hand, there is poor evidence that supports the use of NIMV in other pathologies such as pneumonia, acute respiratory distress syndrome (ARDS), and during procedures as bronchoscopy, where its use is still controversial because the results of these studies are inconclusive against the decrease in the rate of intubation or mortality.

  17. Pathophysiological Basis of Acute Respiratory Failure on Non-Invasive Mechanical Ventilation

    PubMed Central

    Romero-Dapueto, C; Budini, H; Cerpa, F; Caceres, D; Hidalgo, V; Gutiérrez, T; Keymer, J; Pérez, R; Molina, J; Giugliano-Jaramillo, C

    2015-01-01

    Noninvasive mechanical ventilation (NIMV) was created for patients who needed noninvasive ventilator support, this procedure decreases the complications associated with the use of endotracheal intubation (ETT). The application of NIMV has acquired major relevance in the last few years in the management of acute respiratory failure (ARF), in patients with hypoxemic and hypercapnic failure. The main advantage of NIMV as compared to invasive mechanical ventilation (IMV) is that it can be used earlier outside intensive care units (ICUs). The evidence strongly supports its use in patients with COPD exacerbation, support in weaning process in chronic obstructive pulmonary disease (COPD) patients, patients with acute cardiogenic pulmonary edema (ACPE), and Immunosuppressed patients. On the other hand, there is poor evidence that supports the use of NIMV in other pathologies such as pneumonia, acute respiratory distress syndrome (ARDS), and during procedures as bronchoscopy, where its use is still controversial because the results of these studies are inconclusive against the decrease in the rate of intubation or mortality. PMID:26312101

  18. [Reflections on the use of non-invasive mechanical ventilation in acute respiratory failure].

    PubMed

    Scala, Raffaele

    2012-12-01

    Given its prevalence into the clinical practice, non-invasive ventilation (NIV) can be included among the cornerstones of medicine. Just think of the acute applications of NIV which are in constant expansion, from COPD exacerbation to severe de novo hypoxemia, from postoperative distress to extra-hospital use in acute pulmonary edema, from ongoing support of interventional procedures to delicate strategies for end of life in terminally ill oncologic and non-oncologic patients. The thought should be focused on how, by whom, where and to whom is delivered this mode of artificial ventilation to avoid the risk of trivialization and flattening.

  19. Flexible bronchoscopy during non-invasive positive pressure mechanical ventilation: are two better than one?

    PubMed

    Scala, Raffaele

    2016-09-01

    Flexible bronchoscopy (FBO) and non-invasive positive pressure ventilation (NIPPV) are largely applied in respiratory and general intensive care units. FBO plays a crucial role for the diagnosis of lung infiltrates of unknown origin and for the treatment of airways obstruction due to bronchial mucous plugging and hemoptysis in critical patients. NIPPV is the first-choice ventilatory strategy for acute respiratory failure (ARF) of different causes as it could be used as prevention or as alternative to the conventional mechanical ventilation (CMV) via endotracheal intubation (ETI). Some clinical scenarios represent contraindications for these techniques such as severe ARF in spontaneous breathing patients for FBO and accumulated tracheo-bronchial secretions in patients with depressed cough for NIPPV. In these contexts, the decision of performing ETI should carefully consider the risk of CMV-correlated complications. An increasing amount of published data suggested the use of FBO during NIPPV in ARF in order to avoid/reduce the need of ETI. Despite a strong rationale for the combined use of the two techniques, there is not still enough evidence for a large-scale application of this strategy in all different clinical scenarios. The majority of the available data are in favor of the "help" given by NIPPV to diagnostic FBO in high-risk spontaneously breathing patients with severe hypoxemia. Preliminary findings report the successful "help" given by early FBO to NIPPV in patients with hypoxemic-hypercapnic ARF who are likely to fail because of hypersecretion. Synergy of FBO and NIPPV application is emerging also to perform ETI in challenging situations, such as predicted difficult laringoscopy and NPPV failure in severely hypoxemic patients. This combined approach should be performed only in centers showing a wide experience with both NIPPV and FBO, where close monitoring and ETI facilities are promptly available.

  20. Home Mechanical Ventilation in Children.

    PubMed

    Preutthipan, Aroonwan

    2015-09-01

    The number of children dependent on home mechanical ventilation has been reported to be increasing in many countries around the world. Home mechanical ventilation has been well accepted as a standard treatment of children with chronic respiratory failure. Some children may need mechanical ventilation as a lifelong therapy. To send mechanically ventilated children back home may be more difficult than adults. However, relatively better outcomes have been demonstrated in children. Children could be safely ventilated at home if they are selected and managed properly. Conditions requiring home ventilation include increased respiratory load from airway or lung pathologies, ventilatory muscle weakness and failure of neurologic control of ventilation. Home mechanical ventilation should be considered when the patient develops progressive respiratory failure or intractable failure to wean mechanical ventilation. Polysomnography or overnight pulse oximetry plus capnometry are used to detect nocturnal hypoventilation in early stage of respiratory failure. Ventilator strategy including non-invasive and invasive approach should be individualized for each patient. The author strongly believes that parents and family members are able to take care of their child at home if they are trained and educated effectively. A good team work with dedicated members is the key factor of success.

  1. Non-invasive assessment of cardiac output during mechanical ventilation - a novel approach using an inert gas rebreathing method.

    PubMed

    Nickl, Werner; Bugaj, Till; Mondritzki, Thomas; Kuhlebrock, Kathrin; Dinh, Winfried; Krahn, Thomas; Sohler, Florian; Truebel, Hubert

    2011-06-01

    Measurement of cardiac output (CO) is of importance in the diagnostic of critically ill patients. The invasive approach of thermodilution (TD) via pulmonary artery catheter is clinically widely used. A new non-invasive technique of inert gas rebreathing (IGR) shows a good correlation with TD measurements in spontaneously breathing individuals. For the first time, we investigated whether IGR can also be applied to sedated and mechanically ventilated subjects with a clinical point of care device. CO data from IGR were compared with TD in six healthy mongrel dogs. Data sampling was repeated under baseline conditions (rest) and under stress challenge by applying 10 μg/kg/min of dobutamine intravenously. Switching from mechanical ventilation to IGR, as well as the rebreathing procedures, were carried out manually. Cardiac output data from IGR and TD correlated with a coefficient of r=0.90 (95% confidence interval [0.81; 0.95]). The Bland-Altman analysis showed a bias of 0.46 l/min for the IGR CO measurements. Ninety-five percent of all differences fall in the interval [-1.03; 1.95], being the limit of the ± 1.96 standard deviation lines. IGR is a new approach for non-invasive cardiac output measurement in mechanically ventilated individuals, but requires further investigation for clinical use.

  2. Non-invasive ventilation.

    PubMed Central

    Spence, D.

    1996-01-01

    Nasal intermittent positive pressure ventilation is an effective treatment for nocturnal hypoventilation secondary to chest wall deformity or respiratory muscle weakness. Physicians should be aware that, in these groups of patients, disabling breathlessness can be alleviated and established cor pulmonale reversed by the technique. Images Figure 1 Figure 2 Figure 3 PMID:8949588

  3. Development and evaluation of an appraisal form to assess clinical effectiveness of adult invasive mechanical ventilation systems

    PubMed Central

    2012-01-01

    Background Rapid developments in intensive care medicine have made mechanical ventilation an essential method in the resuscitation and comprehensive treatment of critical care patients. This study aimed to develop and evaluate an appraisal form assessing the clinical effectiveness of adult invasive mechanical ventilation systems. Methods An appraisal form was designed according to the effectiveness evaluation theory of the American Weapons Systems Effectiveness Industry Advisory Committee (WSEIAC) along with literature review and expert panel review. Content validity of the preliminary form was analyzed in a cohort of 200 patients. Exploratory and confirmatory factor analysis was used to assess appraisal form validity. Discriminate validity of different ventilation outcomes was analyzed by t test. Test/retest reliability and inter-scorer reliability were evaluated with 30 patients after a 2-week interval by Cronbach's alpha. Results Exploratory factor analysis showed eigenvalues for 3 dimensions (availability, dependability, capability) to be 7.85, 4.43, and 4.22, respectively. Cronbach’s α for internal consistency of the appraisal form was 0.957, and 0.922, 0.961 and 0.937, respectively, for the 3 dimensions. Test-retest reliability of 3 dimensions was 0.976, and 0.862, 0.857, 0.885, respectively. Intra-class correlation coefficient verified test-retest reliability; ICC 0.976 and 0.862, 0.857, 0.885 for 3 dimensions, respectively. Conclusions The appraisal form for clinical effectiveness of adult invasive mechanical ventilation systems has high reliability and validity and may be used in clinical setting. PMID:22747895

  4. Inhalation therapy in mechanical ventilation

    PubMed Central

    Maccari, Juçara Gasparetto; Teixeira, Cassiano; Gazzana, Marcelo Basso; Savi, Augusto; Dexheimer-Neto, Felippe Leopoldo; Knorst, Marli Maria

    2015-01-01

    Patients with obstructive lung disease often require ventilatory support via invasive or noninvasive mechanical ventilation, depending on the severity of the exacerbation. The use of inhaled bronchodilators can significantly reduce airway resistance, contributing to the improvement of respiratory mechanics and patient-ventilator synchrony. Although various studies have been published on this topic, little is known about the effectiveness of the bronchodilators routinely prescribed for patients on mechanical ventilation or about the deposition of those drugs throughout the lungs. The inhaled bronchodilators most commonly used in ICUs are beta adrenergic agonists and anticholinergics. Various factors might influence the effect of bronchodilators, including ventilation mode, position of the spacer in the circuit, tube size, formulation, drug dose, severity of the disease, and patient-ventilator synchrony. Knowledge of the pharmacological properties of bronchodilators and the appropriate techniques for their administration is fundamental to optimizing the treatment of these patients. PMID:26578139

  5. Pulmonary mechanics during mechanical ventilation.

    PubMed

    Henderson, William R; Sheel, A William

    2012-03-15

    The use of mechanical ventilation has become widespread in the management of hypoxic respiratory failure. Investigations of pulmonary mechanics in this clinical scenario have demonstrated that there are significant differences in compliance, resistance and gas flow when compared with normal subjects. This paper will review the mechanisms by which pulmonary mechanics are assessed in mechanically ventilated patients and will review how the data can be used for investigative research purposes as well as to inform rational ventilator management.

  6. Intraoperative mechanical ventilation for the pediatric patient.

    PubMed

    Kneyber, Martin C J

    2015-09-01

    Invasive mechanical ventilation is required when children undergo general anesthesia for any procedure. It is remarkable that one of the most practiced interventions such as pediatric mechanical ventilation is hardly supported by any scientific evidence but rather based on personal experience and data from adults, especially as ventilation itself is increasingly recognized as a harmful intervention that causes ventilator-induced lung injury. The use of low tidal volume and higher levels of positive end-expiratory pressure became an integral part of lung-protective ventilation following the outcomes of clinical trials in critically ill adults. This approach has been readily adopted in pediatric ventilation. However, a clear association between tidal volume and mortality has not been ascertained in pediatrics. In fact, experimental studies have suggested that young children might be less susceptible to ventilator-induced lung injury. As such, no recommendations on optimal lung-protective ventilation strategy in children with or without lung injury can be made.

  7. Conventional mechanical ventilation

    PubMed Central

    Tobias, Joseph D.

    2010-01-01

    The provision of mechanical ventilation for the support of infants and children with respiratory failure or insufficiency is one of the most common techniques that are performed in the Pediatric Intensive Care Unit (PICU). Despite its widespread application in the PICUs of the 21st century, before the 1930s, respiratory failure was uniformly fatal due to the lack of equipment and techniques for airway management and ventilatory support. The operating rooms of the 1950s and 1960s provided the arena for the development of the manual skills and the refinement of the equipment needed for airway management, which subsequently led to the more widespread use of endotracheal intubation thereby ushering in the era of positive pressure ventilation. Although there seems to be an ever increasing complexity in the techniques of mechanical ventilation, its successful use in the PICU should be guided by the basic principles of gas exchange and the physiology of respiratory function. With an understanding of these key concepts and the use of basic concepts of mechanical ventilation, this technique can be successfully applied in both the PICU and the operating room. This article reviews the basic physiology of gas exchange, principles of pulmonary physiology, and the concepts of mechanical ventilation to provide an overview of the knowledge required for the provision of conventional mechanical ventilation in various clinical arenas. PMID:20927268

  8. Predictive value of daily living score in acute respiratory failure of COPD patients requiring invasive mechanical ventilation pilot study

    PubMed Central

    2012-01-01

    Background Mechanical ventilation (MV) is imperative in many forms of acute respiratory failure (ARF) in COPD patients. Previous studies have shown the difficulty to identify parameters predicting the outcome of COPD patients treated by invasive MV. Our hypothesis was that a non specialized score as the activities daily living (ADL) score may help to predict the outcome of these patients. Methods We studied the outcome of 25 COPD patients admitted to the intensive care unit for ARF requiring invasive MV. The patients were divided into those weaning success (group A n = 17, 68%) or failure (group B n = 8, 32%). We investigated the correlation between the ADL score and the outcome and mortality. Results The ADL score was higher in group A (5.1 ±1.1 vs 3.7 ± 0.7 in group B, p < 0.01). Weaning was achieved in 76.5% of the cases with an ADL score ≥ 4 and in 23.5% of the cases with an ADL score < 4 (p < 0.05). Pulmonary function test, arterial blood gases collected during period of clinical stability and at admission and nutritional status were similar in both groups. The mortality, at six months, was 36%. The ADL score was a significant predictor of 6-month mortality (80 with an ADL score <4, 20 with an ADL score ≥4, p < 0.01). Conclusion Our pilot study demonstrates that the ADL score is predictive of weaning success and mortality at 6 months, suggesting that the assessment of daily activities should be an important component of ARF management in COPD patients. PMID:23078114

  9. Non-invasive ventilation in acute cardiogenic pulmonary oedema

    PubMed Central

    Agarwal, R; Aggarwal, A; Gupta, D; Jindal, S

    2005-01-01

    Non-invasive ventilation (NIV) is the delivery of assisted mechanical ventilation to the lungs, without the use of an invasive endotracheal airway. NIV has revolutionised the management of patients with various forms of respiratory failure. It has decreased the need for invasive mechanical ventilation and its attendant complications. Cardiogenic pulmonary oedema (CPO) is a common medical emergency, and NIV has been shown to improve both physiological and clinical outcomes. From the data presented herein, it is clear that there is sufficiently high level evidence to favour the use of continuous positive airway pressure (CPAP), and that the use of CPAP in patients with CPO decreases intubation rate and improves survival (number needed to treat seven and eight respectively). However, there is insufficient evidence to recommend the use of bilevel positive airway pressure (BiPAP), probably the exception being patients with hypercapnic CPO. More trials are required to conclusively define the role of BiPAP in CPO. PMID:16210459

  10. Understanding mechanical ventilators.

    PubMed

    Chatburn, Robert L

    2010-12-01

    The respiratory care academic community has not yet adopted a standardized system for classifying and describing modes of ventilation. As a result, there is enough confusion that patient care, clinician education and even ventilator sales are all put at risk. This article summarizes a ventilator mode taxonomy that has been extensively published over the last 15 years. Specifically, the classification system has three components: a description of the control variables within breath; a description of the sequence of mandatory and spontaneous breaths; and a specification for the targeting scheme. This three-level specification provides scalability of detail to make the mode description appropriate for the particular need. At the bedside, we need only refer to a mode briefly using the first or perhaps first and second components. To distinguish between similar modes and brand names, we would need to include all components. This taxonomy uses the equation of motion for the respiratory system as the underlying theoretical framework. All terms relevant to describing modes of mechanical ventilation are defined in an extensive appendix.

  11. Home Mechanical Ventilation in South Korea

    PubMed Central

    Kim, Dong Hyun; Choi, Won Ah

    2014-01-01

    Purpose To survey the use of invasive and noninvasive home mechanical ventilation (HMV) methods in South Korea from the perspective of physical medicine and rehabilitation (PM&R). Materials and Methods For 413 users of HMV, retrospective reviews of PM&R interventions and survey of HMV methods employed from Mar 2000 to Dec 2009. Results Of the 413 users, the majority of whom with progressive neuromuscular disorders (NMDs) (n=358), 284 patients initially used noninvasive mechanical ventilation (NIV), while 63 others who were using tracheostomy mechanical ventilation switched to NIV as part of their rehabilitation. The NMD patients began HMV at an earlier age (34.9±20.3 yrs), and used for longer (14.7±7.5) hours than patients with non-neuromuscular causes of respiratory impairment. Conclusion Noninvasive management was preferred over invasive ones, and transition to the former was a result of PM&R interventions. PMID:25323913

  12. [Mechanical ventilation at home: facts and questions].

    PubMed

    Fitting, J W

    1993-06-15

    Treatment of respiratory insufficiency with retention of CO2 by mechanic ventilation has come into use over the last decade, favored by use of non-invasive methods like nasal ventilation. Best results have been observed in hypercapnic respiratory insufficiency caused by neuromuscular disease or restrictive pathologic changes of the lung. Nocturnal use of nasal ventilation alone is often sufficient to correct also the daily CO2-values. Mechanisms explaining this beneficial effect are not yet known-The respiratory CNS-centers, respiratory muscles or thoracopulmonary mechanics may play etiologically an important role. Medical indications for nasal ventilation in chronic obstructive pulmonary disease are not clear, since results from several studies are controversial. Also in severe or progressive neurologic diseases a critical evaluation is mandatory for assessment of benefits including improvement of quality of life.

  13. Ventilation and respiratory mechanics.

    PubMed

    Sheel, Andrew William; Romer, Lee M

    2012-04-01

    During dynamic exercise, the healthy pulmonary system faces several major challenges, including decreases in mixed venous oxygen content and increases in mixed venous carbon dioxide. As such, the ventilatory demand is increased, while the rising cardiac output means that blood will have considerably less time in the pulmonary capillaries to accomplish gas exchange. Blood gas homeostasis must be accomplished by precise regulation of alveolar ventilation via medullary neural networks and sensory reflex mechanisms. It is equally important that cardiovascular and pulmonary system responses to exercise be precisely matched to the increase in metabolic requirements, and that the substantial gas transport needs of both respiratory and locomotor muscles be considered. Our article addresses each of these topics with emphasis on the healthy, young adult exercising in normoxia. We review recent evidence concerning how exercise hyperpnea influences sympathetic vasoconstrictor outflow and the effect this might have on the ability to perform muscular work. We also review sex-based differences in lung mechanics.

  14. Mechanical ventilation in abdominal surgery.

    PubMed

    Futier, E; Godet, T; Millot, A; Constantin, J-M; Jaber, S

    2014-01-01

    One of the key challenges in perioperative care is to reduce postoperative morbidity and mortality. Patients who develop postoperative morbidity but survive to leave hospital have often reduced functional independence and long-term survival. Mechanical ventilation provides a specific example that may help us to shift thinking from treatment to prevention of postoperative complications. Mechanical ventilation in patients undergoing surgery has long been considered only as a modality to ensure gas exchange while allowing maintenance of anesthesia with delivery of inhaled anesthetics. Evidence is accumulating, however, suggesting an association between intraoperative mechanical ventilation strategy and postoperative pulmonary function and clinical outcome in patients undergoing abdominal surgery. Non-protective ventilator settings, especially high tidal volume (VT) (>10-12mL/kg) and the use of very low level of positive end-expiratory pressure (PEEP) (PEEP<5cmH2O) or no PEEP, may cause alveolar overdistension and repetitive tidal recruitment leading to ventilator-associated lung injury in patients with healthy lungs. Stimulated by previous findings in patients with acute respiratory distress syndrome, the use of lower tidal volume ventilation is becoming increasingly more common in the operating room. However, lowering tidal volume, though important, is only part of the overall multifaceted approach of lung protective mechanical ventilation. In this review, we aimed at providing the most recent and relevant clinical evidence regarding the use of mechanical ventilation in patients undergoing abdominal surgery.

  15. Difficult weaning from mechanical ventilation.

    PubMed

    Oh, T E

    1994-07-01

    Weaning from mechanical ventilation may be influenced by factors relating to equipment, techniques and procedures. Criteria to initiate weaning and predictors of weaning outcome are generally unreliable, but mechanical work of breathing, the tidal volume: frequency ratio and the inspiratory pressure: maximal inspiratory pressure ratio may anticipate those likely to fail weaning. The optimal weaning ventilatory mode is not known, but intermittent mandatory ventilation, pressure support ventilation, and continuous positive pressure ventilation are the most commonly used. The resistances of individual components of breathing circuits are extremely important. Blow-by heated humidifiers and ventilators which compensate for the impedances of their inspiratory demand valves impose clinically acceptable spontaneous breathing loads. Close monitoring, adequate respiratory muscle rest, attention to mineral deficiencies, nutrition and pulmonary hygiene are also important parts of the weaning process.

  16. Application of fiberoptic bronchscopy in patients with acute exacerbations of chronic obstructive pulmonary disease during sequential weaning of invasive-noninvasive mechanical ventilation

    PubMed Central

    Song, Rong-rong; Qiu, Yan-ping; Chen, Yong-ju; Ji, Yong

    2012-01-01

    BACKGROUND: Early withdrawal of invasive mechanical ventilation (IMV) followed by noninvasive MV (NIMV) is a new strategy for changing modes of treatment in patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) with acute respiratory failure (ARF). Using pulmonary infection control window (PIC window) as the switch point for transferring from invasive to noninvasive MV, the time for early extubation can be more accurately judged, and therapy efficacy can be improved. This study aimed to prospectively investigate the clinical effectiveness of fiberoptic bronchscopy (FOB) in patients with AECOPD during sequential weaning of invasive-noninvasive MV. METHODS: Since July 2006 to January 2011, 106 AECOPD patients with ARF were treated with comprehensive medication and IMV after hospitalization. Patients were randomly divided into two groups according to whether fiberoptic bronchoscope is used (group A, n=54) or not (group B, n=52) during sequential weaning from invasive to noninvasive MV. In group A, for sputum suction and bronchoalveolar lavage (BAL), a fiberoptic bronchoscope was put into the airway from the outside of an endotracheal tube, which was accompanied with uninterrupted use of a ventilator. After achieving PIC window, patients of both groups changed to NIMV mode, and weaned from ventilation. The following listed indices were used to compare between the groups after treatment: 1) the occurrence time of PIC, the duration of MV, the length of ICU stay, the success rate of weaning from MV for the first time, the rate of reventilation and the occurrence rate of ventilator-associated pneumonia (VAP); 2) the convenience and safety of FOB manipulation. The results were compared using Student’s t test and the Chi-square test. RESULTS: The occurrence time of PIC was (5.01±1.49) d, (5.87±1.87) d in groups A and B, respectively (P<0.05); the duration of MV was (6.98±1.84) d, (8.69±2.41) d in groups A and B, respectively (P<0.01); the

  17. Basic concepts in mechanical ventilation.

    PubMed

    Carbery, Catherine

    2008-03-01

    Mechanical ventilatory support is a major component of the clinical management of critically ill patients admitted into intensive care. Closely linked with the developments within critical care medicine, the use of ventilatory support has been increasing since the polio epidemics in the 1950s (Lassen 1953). Initially used to provide controlled mandatory ventilation, today with advances in technology, most mechanical ventilators are triggered by the patient, increasing the awareness of the complexity of patient/ventilator interaction (Tobin 1994). Though ventilator appearance and design may have changed quite significantly and the variety of options for support extensive, the basic concepts of mechanical ventilatory support of the critically ill patient remains unchanged. This paper aims to outline these concepts so as to gain a better understanding of mechanical ventilatory support.

  18. Long-term non-invasive ventilation in children.

    PubMed

    Amaddeo, Alessandro; Frapin, Annick; Fauroux, Brigitte

    2016-12-01

    Use of long-term non-invasive ventilation is increasing exponentially worldwide in children of all ages. The treatment entails delivery of ventilatory assistance through a non-invasive interface. Indications for use of non-invasive ventilation include conditions that affect normal respiratory balance (eg, those associated with dysfunction of the central drive or respiratory muscles) and disorders characterised by an increase in respiratory load (eg, obstructive airway or lung diseases). The type of non-invasive ventilation used depends on the pathophysiological features of the respiratory failure. For example, non-invasive ventilation will need to either replace central drive if the disorder is characterised by an abnormal central drive or substitute for the respiratory muscles if the condition is associated with respiratory muscle weakness. Non-invasive ventilation might also need to unload the respiratory muscles in case of an increase in respiratory load, as seen in upper airway obstruction and some lung diseases. Technical aspects are also important when choosing non-invasive ventilation-eg, appropriate interface and device. The great heterogeneity of disorders, age ranges of affected children, prognoses, and outcomes of patients needing long-term non-invasive ventilation underline the need for management by skilled multidisciplinary centres with technical competence in paediatric non-invasive ventilation and expertise in sleep studies and therapeutic education.

  19. Prognosis of mechanically ventilated patients.

    PubMed Central

    Papadakis, M A; Lee, K K; Browner, W S; Kent, D L; Matchar, D B; Kagawa, M K; Hallenbeck, J; Lee, D; Onishi, R; Charles, G

    1993-01-01

    In this Department of Veterans Affairs cooperative study, we examined predictors of in-hospital and 1-year mortality of 612 mechanically ventilated patients from 6 medical intensive care units in a retrospective cohort design. The outcome variable was vital status at hospital discharge and after 1 year. The results showed that 97% of patients were men, the mean age was 63 +/- 11 years (SD), and hospital mortality was 64% (95% confidence interval, 60% to 68%). Within the next year, an additional 38% of hospital survivors died, for a total 1-year mortality of 77% (95% confidence interval, 73% to 80%). Hospital and 1-year mortality, respectively, for patients older than 70 years was 76% and 94%, for those with serum albumin levels below 20 grams per liter it was 92% and 96%, for those with an Acute Physiology and Chronic Health Evaluation II (APACHE II) score greater than 35 it was 91% and 98%, and for patients who were being mechanically ventilated after cardiopulmonary resuscitation it was 86% and 90%. The mortality ratio (actual mortality versus APACHE II-predicted mortality) was 1.15. Conclusions are that patient age, APACHE II score, serum albumin levels, or the use of cardiopulmonary resuscitation may identify a subset of mechanically ventilated veterans for whom mechanical ventilation provides little or no benefit. PMID:8128673

  20. Diaphragm Dysfunction in Mechanically Ventilated Patients.

    PubMed

    Dot, Irene; Pérez-Teran, Purificación; Samper, Manuel-Andrés; Masclans, Joan-Ramon

    2017-03-01

    Muscle involvement is found in most critical patients admitted to the intensive care unit (ICU). Diaphragmatic muscle alteration, initially included in this category, has been differentiated in recent years, and a specific type of muscular dysfunction has been shown to occur in patients undergoing mechanical ventilation. We found this muscle dysfunction to appear in this subgroup of patients shortly after the start of mechanical ventilation, observing it to be mainly associated with certain control modes, and also with sepsis and/or multi-organ failure. Although the specific etiology of process is unknown, the muscle presents oxidative stress and mitochondrial changes. These cause changes in protein turnover, resulting in atrophy and impaired contractility, and leading to impaired functionality. The term 'ventilator-induced diaphragm dysfunction' was first coined by Vassilakopoulos et al. in 2004, and this phenomenon, along with injury cause by over-distention of the lung and barotrauma, represents a challenge in the daily life of ventilated patients. Diaphragmatic dysfunction affects prognosis by delaying extubation, prolonging hospital stay, and impairing the quality of life of these patients in the years following hospital discharge. Ultrasound, a non-invasive technique that is readily available in most ICUs, could be used to diagnose this condition promptly, thus preventing delays in starting rehabilitation and positively influencing prognosis in these patients.

  1. Hypercapnic encephalopathy syndrome: a new frontier for non-invasive ventilation?

    PubMed

    Scala, Raffaele

    2011-08-01

    According to the classical international guidelines, non-invasive ventilation is contraindicated in hypercapnic encephalopathy syndrome (HES) due to the poor compliance to ventilatory treatment of confused/agitated patients and the risk of aspirative pneumonia related to lack of airways protection. As a matter of fact, conventional mechanical ventilation has been recommended as "golden standard" in these patients. However, up to now there are not controlled data that have demonstrated in HES the advantage of conventional mechanical ventilation vs non-invasive ventilation. In fact, patients with altered mental status have been systematically excluded from the randomised and controlled trials performed with non-invasive ventilation in hypercapnic acute respiratory failure. Recent studies have clearly demonstrated that an initial cautious NPPV trial in selected HES patients may be attempt as long as there are no other contraindications and the technique is provided by experienced caregivers in a closely monitored setting where ETI is always readily available. The purpose of this review is to report the physiologic rationale, the clinical feasibility and the still open questions about the careful use of non-invasive ventilation in HES as first-line ventilatory strategy in place of conventional mechanical ventilation via endotracheal intubation.

  2. [Non-invasive mechanical ventilation with a facial interface during sedation for a percutaneous endoscopic gastrostomy in a patient with amyotrophic lateral sclerosis].

    PubMed

    González-Frasquet, M C; García-Covisa, N; Vidagany-Espert, L; Herranz-Gordo, A; Llopis-Calatayud, J E

    2015-11-01

    Amyotrophic lateral sclerosis is a chronic neurodegenerative disease of the central nervous system which affects the motor neurons and produces a progressive muscle weakness, leading to atrophy and muscle paralysis, and ultimately death. Performing a percutaneous endoscopic gastrostomy with sedation in patients with amyotrophic lateral sclerosis can be a challenge for the anesthesiologist. The case is presented of a 76-year-old patient who suffered from advanced stage amyotrophic lateral sclerosis, ASA III, in which a percutaneous endoscopic gastrostomy was performed with deep sedation, for which non-invasive ventilation was used as a respiratory support to prevent hypoventilation and postoperative respiratory complications.

  3. A taxonomy for mechanical ventilation: 10 fundamental maxims.

    PubMed

    Chatburn, Robert L; El-Khatib, Mohamad; Mireles-Cabodevila, Eduardo

    2014-11-01

    The American Association for Respiratory Care has declared a benchmark for competency in mechanical ventilation that includes the ability to "apply to practice all ventilation modes currently available on all invasive and noninvasive mechanical ventilators." This level of competency presupposes the ability to identify, classify, compare, and contrast all modes of ventilation. Unfortunately, current educational paradigms do not supply the tools to achieve such goals. To fill this gap, we expand and refine a previously described taxonomy for classifying modes of ventilation and explain how it can be understood in terms of 10 fundamental constructs of ventilator technology: (1) defining a breath, (2) defining an assisted breath, (3) specifying the means of assisting breaths based on control variables specified by the equation of motion, (4) classifying breaths in terms of how inspiration is started and stopped, (5) identifying ventilator-initiated versus patient-initiated start and stop events, (6) defining spontaneous and mandatory breaths, (7) defining breath sequences (8), combining control variables and breath sequences into ventilatory patterns, (9) describing targeting schemes, and (10) constructing a formal taxonomy for modes of ventilation composed of control variable, breath sequence, and targeting schemes. Having established the theoretical basis of the taxonomy, we demonstrate a step-by-step procedure to classify any mode on any mechanical ventilator.

  4. Economics of mechanical ventilation and respiratory failure.

    PubMed

    Cooke, Colin R

    2012-01-01

    For patients with acute respiratory failure, mechanical ventilation provides the most definitive life-sustaining therapy. Because of the intense resources required to care for these patients, its use accounts for considerable costs. There is great societal need to ensure that use of mechanical ventilation maximizes societal benefits while minimizing costs, and that mechanical ventilation, and ventilator support in general, is delivered in the most efficient and cost-effective manner. This review summarizes the economic aspects of mechanical ventilation and summarizes the existing literature that examines its economic impact cost effectiveness.

  5. Modes of mechanical ventilation for the operating room.

    PubMed

    Ball, Lorenzo; Dameri, Maddalena; Pelosi, Paolo

    2015-09-01

    Most patients undergoing surgical procedures need to be mechanically ventilated, because of the impact of several drugs administered at induction and during maintenance of general anaesthesia on respiratory function. Optimization of intraoperative mechanical ventilation can reduce the incidence of post-operative pulmonary complications and improve the patient's outcome. Preoxygenation at induction of general anaesthesia prolongs the time window for safe intubation, reducing the risk of hypoxia and overweighs the potential risk of reabsorption atelectasis. Non-invasive positive pressure ventilation delivered through different interfaces should be considered at the induction of anaesthesia morbidly obese patients. Anaesthesia ventilators are becoming increasingly sophisticated, integrating many functions that were once exclusive to intensive care. Modern anaesthesia machines provide high performances in delivering the desired volumes and pressures accurately and precisely, including assisted ventilation modes. Therefore, the physicians should be familiar with the potential and pitfalls of the most commonly used intraoperative ventilation modes: volume-controlled, pressure-controlled, dual-controlled and assisted ventilation. Although there is no clear evidence to support the advantage of any one of these ventilation modes over the others, protective mechanical ventilation with low tidal volume and low levels of positive end-expiratory pressure (PEEP) should be considered in patients undergoing surgery. The target tidal volume should be calculated based on the predicted or ideal body weight rather than on the actual body weight. To optimize ventilation monitoring, anaesthesia machines should include end-inspiratory and end-expiratory pause as well as flow-volume loop curves. The routine administration of high PEEP levels should be avoided, as this may lead to haemodynamic impairment and fluid overload. Higher PEEP might be considered during surgery longer than 3 h

  6. [Invasive and non-invasive ventilation in conflict with best palliative care in severe COPD].

    PubMed

    Mikesch, Martin; Reichenpfader, Peter

    2009-12-01

    This example of an 80-year-old patient with severe lung disease and respiratory failure demonstrates the difficult relationship between the patient's needs, physical symptoms, and social problems. This man decides after a prolonged and difficult in-patient treatment actively for home ventilation rather than die of respiratory failure. He opts for tracheostomy and invasive ventilation because he cannot handle non-invasive mask-ventilation sufficiently by himself. It requires professional communication and support to gain the acceptance of family and caregivers for home ventilation. A survey of existing data on end of life decision-making in end-stage lung disease is given.

  7. Estimating Respiratory Mechanical Parameters during Mechanical Ventilation

    PubMed Central

    Barbini, Paolo

    1982-01-01

    We propose an algorithm for the estimation of the parameters of the mechanical respiratory system. The algorithm is based on non linear regression analysis with a two-compartment respiratory system model. The model used allows us to take account of the non homogeneous properties of the lungs which may cause uneven distribution of ventilation and thus affect the gas exchange in the lungs. The estimation of the parameters of such a model permits the optimization of the type of ventilation to be used in patients undergoing respiratory treatment. This can be done bearing in mind the effects of the mechanical ventilation on venous return as well as the quality of gas exchange. We have valued the performances of the estimation algorithm which is proposed on the basis of the agreement between the data and the model response, of the stability of the parameter estimates and of the standard deviations of the parameters. The parameter estimation algorithm described does not have recourse to the examination of the impedance spectra and is completely independent of the type of ventilator employed.

  8. Assisted mechanical ventilation: the future is now!

    PubMed

    Kacmarek, Robert M; Pirrone, Massimiliano; Berra, Lorenzo

    2015-07-29

    Assisted ventilation is a highly complex process that requires an intimate interaction between the ventilator and the patient. The complexity of this form of ventilation is frequently underappreciated by the bedside clinician. In assisted mechanical ventilation, regardless of the specific mode, the ventilator's gas delivery pattern and the patient's breathing pattern must match near perfectly or asynchrony between the patient and the ventilator occurs. Asynchrony can be categorized into four general types: flow asynchrony; trigger asynchrony; cycle asynchrony; and mode asynchrony. In an article recently published in BMC Anesthesiology, Hodane et al. have demonstrated reduced asynchrony during assisted ventilation with Neurally Adjusted Ventilatory Assist (NAVA) as compared to pressure support ventilation (PSV). These findings add to the growing volume of data indicating that modes of ventilation that provide proportional assistance to ventilation - e.g., NAVA and Proportional Assist Ventilation (PAV) - markedly reduce asynchrony. As it becomes more accepted that the respiratory center of the patient in most circumstances is the most appropriate determinant of ventilatory pattern and as the negative outcome effects of patient-ventilator asynchrony become ever more recognized, we can expect NAVA and PAV to become the preferred modes of assisted ventilation!

  9. Respiratory mechanics in mechanically ventilated patients.

    PubMed

    Hess, Dean R

    2014-11-01

    Respiratory mechanics refers to the expression of lung function through measures of pressure and flow. From these measurements, a variety of derived indices can be determined, such as volume, compliance, resistance, and work of breathing. Plateau pressure is a measure of end-inspiratory distending pressure. It has become increasingly appreciated that end-inspiratory transpulmonary pressure (stress) might be a better indicator of the potential for lung injury than plateau pressure alone. This has resulted in a resurgence of interest in the use of esophageal manometry in mechanically ventilated patients. End-expiratory transpulmonary pressure might also be useful to guide the setting of PEEP to counterbalance the collapsing effects of the chest wall. The shape of the pressure-time curve might also be useful to guide the setting of PEEP (stress index). This has focused interest in the roles of stress and strain to assess the potential for lung injury during mechanical ventilation. This paper covers both basic and advanced respiratory mechanics during mechanical ventilation.

  10. Nursing care of the mechanically ventilated patient in ITU: 1.

    PubMed

    Ashurst, S

    The mechanically ventilated patient often represents the ultimate in vulnerability and demands the highest standards of nursing care. Not only may the patient be unconscious but also the artificial airway is an unnatural invasion of the most innate physiological mechanism--breathing, and the nurse must safeguard this during all aspects of care. Nursing these patients is immensely satisfying and varied. It ranges from caring for the patient's activities of daily living to carrying out the highly technical and invasive monitoring and interventions which require specialist knowledge and skills. This article, the first in a two-part series, covers the types of ventilation, suction therapy, oral and eye care, elimination, body position, physiotherapy and the physiological effects of mechanical ventilation.

  11. [Non-invasive ventilation and acute cardiogenic pulmonary oedema].

    PubMed

    Golmard, Céline

    2015-11-01

    Non-invasive ventilation is an integral part of therapies used in patients presenting acute cardiogenic pulmonary oedema. In cardiac intensive care, these patients are treated by teams trained and practised in this technique. The nurses play a central role in the support and monitoring of the patients.

  12. Exercise oscillatory ventilation: Mechanisms and prognostic significance

    PubMed Central

    Dhakal, Bishnu P; Lewis, Gregory D

    2016-01-01

    Alteration in breathing patterns characterized by cyclic variation of ventilation during rest and during exercise has been recognized in patients with advanced heart failure (HF) for nearly two centuries. Periodic breathing (PB) during exercise is known as exercise oscillatory ventilation (EOV) and is characterized by the periods of hyperpnea and hypopnea without interposed apnea. EOV is a non-invasive parameter detected during submaximal cardiopulmonary exercise testing. Presence of EOV during exercise in HF patients indicates significant impairment in resting and exercise hemodynamic parameters. EOV is also an independent risk factor for poor prognosis in HF patients both with reduced and preserved ejection fraction irrespective of other gas exchange variables. Circulatory delay, increased chemosensitivity, pulmonary congestion and increased ergoreflex signaling have been proposed as the mechanisms underlying the generation of EOV in HF patients. There is no proven treatment of EOV but its reversal has been noted with phosphodiesterase inhibitors, exercise training and acetazolamide in relatively small studies. In this review, we discuss the mechanistic basis of PB during exercise and the clinical implications of recognizing PB patterns in patients with HF. PMID:27022457

  13. Humidification during Mechanical Ventilation in the Adult Patient

    PubMed Central

    Al Ashry, Haitham S.; Modrykamien, Ariel M.

    2014-01-01

    Humidification of inhaled gases has been standard of care in mechanical ventilation for a long period of time. More than a century ago, a variety of reports described important airway damage by applying dry gases during artificial ventilation. Consequently, respiratory care providers have been utilizing external humidifiers to compensate for the lack of natural humidification mechanisms when the upper airway is bypassed. Particularly, active and passive humidification devices have rapidly evolved. Sophisticated systems composed of reservoirs, wires, heating devices, and other elements have become part of our usual armamentarium in the intensive care unit. Therefore, basic knowledge of the mechanisms of action of each of these devices, as well as their advantages and disadvantages, becomes a necessity for the respiratory care and intensive care practitioner. In this paper, we review current methods of airway humidification during invasive mechanical ventilation of adult patients. We describe a variety of devices and describe the eventual applications according to specific clinical conditions. PMID:25089275

  14. Challenges on non-invasive ventilation to treat acute respiratory failure in the elderly.

    PubMed

    Scala, Raffaele

    2016-11-15

    Acute respiratory failure is a frequent complication in elderly patients especially if suffering from chronic cardio-pulmonary diseases. Non-invasive mechanical ventilation constitutes a successful therapeutic tool in the elderly as, like in younger patients, it is able to prevent endotracheal intubation in a wide range of acute conditions; moreover, this ventilator technique is largely applied in the elderly in whom invasive mechanical ventilation is considered not appropriated. Furthermore, the integration of new technological devices, ethical issues and environment of treatment are still largely debated in the treatment of acute respiratory failure in the elderly.This review aims at reporting and critically analyzing the peculiarities in the management of acute respiratory failure in elderly people, the role of noninvasive mechanical ventilation, the potential advantages of applying alternative or integrated therapeutic tools (i.e. high-flow nasal cannula oxygen therapy, non-invasive and invasive cough assist devices and low-flow carbon-dioxide extracorporeal systems), drawbacks in physician's communication and "end of life" decisions. As several areas of this topic are not supported by evidence-based data, this report takes in account also "real-life" data as well as author's experience.The choice of the setting and of the timing of non-invasive mechanical ventilation in elderly people with advanced cardiopulmonary disease should be carefully evaluated together with the chance of using integrated or alternative supportive devices. Last but not least, economic and ethical issues may often challenges the behavior of the physicians towards elderly people who are hospitalized for acute respiratory failure at the end stage of their cardiopulmonary and neoplastic diseases.

  15. Lemierre's Syndrome Associated with Mechanical Ventilation and Profound Deafness

    PubMed Central

    2017-01-01

    Lemierre's syndrome is a rare disorder that is characterized by anaerobic organisms inducing a thrombophlebitis of the internal jugular vein (IJV) following a course of oropharyngeal infection. It often occurs in young and healthy patients. Clinicians continuously misinterpret early symptoms until infection disseminates systematically and life-threatening sepsis transpires. We report the case of a 58-year-old female developing Lemierre's syndrome accompanied by invasive ventilation support and a profound deafness requiring the implementation of a cochlear implant. This is one of two reported cases of Lemierre's syndrome associated with mechanical ventilation support and the only case associated with a cochlear implant. PMID:28331642

  16. New modes of assisted mechanical ventilation.

    PubMed

    Suarez-Sipmann, F

    2014-05-01

    Recent major advances in mechanical ventilation have resulted in new exciting modes of assisted ventilation. Compared to traditional ventilation modes such as assisted-controlled ventilation or pressure support ventilation, these new modes offer a number of physiological advantages derived from the improved patient control over the ventilator. By implementing advanced closed-loop control systems and using information on lung mechanics, respiratory muscle function and respiratory drive, these modes are specifically designed to improve patient-ventilator synchrony and reduce the work of breathing. Depending on their specific operational characteristics, these modes can assist spontaneous breathing efforts synchronically in time and magnitude, adapt to changing patient demands, implement automated weaning protocols, and introduce a more physiological variability in the breathing pattern. Clinicians have now the possibility to individualize and optimize ventilatory assistance during the complex transition from fully controlled to spontaneous assisted ventilation. The growing evidence of the physiological and clinical benefits of these new modes is favoring their progressive introduction into clinical practice. Future clinical trials should improve our understanding of these modes and help determine whether the claimed benefits result in better outcomes.

  17. Use of non‐invasive ventilation in UK emergency departments

    PubMed Central

    Browning, J; Atwood, B; Gray, A

    2006-01-01

    Aim To describe the current use of non‐invasive ventilation in UK emergency departments. Methods A structured questionnaire was sent to all UK emergency departments assessing 25,000 new patients annually. Results 222 of 233 departments completed the questionnaire. 148 currently use non‐invasive ventilation (NIV). Most used NIV for either cardiogenic pulmonary oedema (n = 128) or chronic obstructive pulmonary disease (n = 115). Only 49 departments have protocols for NIV use and 23 audited practice. Conclusion NIV is commonly used in UK emergency departments. Practices vary significantly. One solution would be the development of guidelines on when and how to use NIV in emergency medicine practice. PMID:17130599

  18. Mechanical ventilation and respiratory mechanics during equine anesthesia.

    PubMed

    Moens, Yves

    2013-04-01

    The mechanical ventilation of horses during anesthesia remains a crucial option for optimal anesthetic management, if the possible negative cardiovascular side effects are managed, because this species is prone to hypercapnia and hypoxemia. The combined use of capnography and pitot-based spirometry provide complementary information on ventilation and respiratory mechanics, respectively. This facilitates management of mechanical ventilation in conditions of changing respiratory system compliance (ie, laparoscopy) and when investigating new ventilatory strategies including alveolar recruitment maneuvers and optimization of positive expiratory pressure.

  19. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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  20. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Mechanical ventilation system: Standards. 154.1205... Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each exhaust type mechanical ventilation system required under § 154.1200 (a) must have ducts...

  1. 46 CFR 154.1200 - Mechanical ventilation system: General.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Mechanical ventilation system: General. 154.1200 Section... Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a... cargo handling equipment must have a fixed, exhaust-type mechanical ventilation system. (b)...

  2. 46 CFR 154.1200 - Mechanical ventilation system: General.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Mechanical ventilation system: General. 154.1200 Section... Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a... cargo handling equipment must have a fixed, exhaust-type mechanical ventilation system. (b)...

  3. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Mechanical ventilation system: Standards. 154.1205... Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each exhaust type mechanical ventilation system required under § 154.1200 (a) must have ducts...

  4. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Mechanical ventilation system: Standards. 154.1205... Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each exhaust type mechanical ventilation system required under § 154.1200 (a) must have ducts...

  5. 46 CFR 154.1200 - Mechanical ventilation system: General.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Mechanical ventilation system: General. 154.1200 Section... Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a... cargo handling equipment must have a fixed, exhaust-type mechanical ventilation system. (b)...

  6. Special Considerations in Neonatal Mechanical Ventilation.

    PubMed

    Dalgleish, Stacey; Kostecky, Linda; Charania, Irina

    2016-12-01

    Care of infants supported with mechanical ventilation is complex, time intensive, and requires constant vigilance by an expertly prepared health care team. Current evidence must guide nursing practice regarding ventilated neonates. This article highlights the importance of common language to establish a shared mental model and enhance clear communication among the interprofessional team. Knowledge regarding the underpinnings of an open lung strategy and the interplay between the pathophysiology and individual infant's response to a specific ventilator strategy is most likely to result in a positive clinical outcome.

  7. Mechanical Ventilation and ARDS in the ED

    PubMed Central

    Mohr, Nicholas M.; Miller, Christopher N.; Deitchman, Andrew R.; Castagno, Nicole; Hassebroek, Elizabeth C.; Dhedhi, Adam; Scott-Wittenborn, Nicholas; Grace, Edward; Lehew, Courtney; Kollef, Marin H.

    2015-01-01

    BACKGROUND: There are few data regarding mechanical ventilation and ARDS in the ED. This could be a vital arena for prevention and treatment. METHODS: This study was a multicenter, observational, prospective, cohort study aimed at analyzing ventilation practices in the ED. The primary outcome was the incidence of ARDS after admission. Multivariable logistic regression was used to determine the predictors of ARDS. RESULTS: We analyzed 219 patients receiving mechanical ventilation to assess ED ventilation practices. Median tidal volume was 7.6 mL/kg predicted body weight (PBW) (interquartile range, 6.9-8.9), with a range of 4.3 to 12.2 mL/kg PBW. Lung-protective ventilation was used in 122 patients (55.7%). The incidence of ARDS after admission from the ED was 14.7%, with a mean onset of 2.3 days. Progression to ARDS was associated with higher illness severity and intubation in the prehospital environment or transferring facility. Of the 15 patients with ARDS in the ED (6.8%), lung-protective ventilation was used in seven (46.7%). Patients who progressed to ARDS experienced greater duration in organ failure and ICU length of stay and higher mortality. CONCLUSIONS: Lung-protective ventilation is infrequent in patients receiving mechanical ventilation in the ED, regardless of ARDS status. Progression to ARDS is common after admission, occurs early, and worsens outcome. Patient- and treatment-related factors present in the ED are associated with ARDS. Given the limited treatment options for ARDS, and the early onset after admission from the ED, measures to prevent onset and to mitigate severity should be instituted in the ED. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01628523; URL: www.clinicaltrials.gov PMID:25742126

  8. Cardiac output estimation using pulmonary mechanics in mechanically ventilated patients

    PubMed Central

    2010-01-01

    The application of positive end expiratory pressure (PEEP) in mechanically ventilated (MV) patients with acute respiratory distress syndrome (ARDS) decreases cardiac output (CO). Accurate measurement of CO is highly invasive and is not ideal for all MV critically ill patients. However, the link between the PEEP used in MV, and CO provides an opportunity to assess CO via MV therapy and other existing measurements, creating a CO measure without further invasiveness. This paper examines combining models of diffusion resistance and lung mechanics, to help predict CO changes due to PEEP. The CO estimator uses an initial measurement of pulmonary shunt, and estimations of shunt changes due to PEEP to predict CO at different levels of PEEP. Inputs to the cardiac model are the PV loops from the ventilator, as well as the oxygen saturation values using known respiratory inspired oxygen content. The outputs are estimates of pulmonary shunt and CO changes due to changes in applied PEEP. Data from two published studies are used to assess and initially validate this model. The model shows the effect on oxygenation due to decreased CO and decreased shunt, resulting from increased PEEP. It concludes that there is a trade off on oxygenation parameters. More clinically importantly, the model also examines how the rate of CO drop with increased PEEP can be used as a method to determine optimal PEEP, which may be used to optimise MV therapy with respect to the gas exchange achieved, as well as accounting for the impact on the cardiovascular system and its management. PMID:21108836

  9. Brazilian recommendations of mechanical ventilation 2013. Part I

    PubMed Central

    Barbas, Carmen Sílvia Valente; Ísola, Alexandre Marini; Farias, Augusto Manoel de Carvalho; Cavalcanti, Alexandre Biasi; Gama, Ana Maria Casati; Duarte, Antonio Carlos Magalhães; Vianna, Arthur; Serpa, Ary; Bravim, Bruno de Arruda; Pinheiro, Bruno do Valle; Mazza, Bruno Franco; de Carvalho, Carlos Roberto Ribeiro; Toufen, Carlos; David, Cid Marcos Nascimento; Taniguchi, Corine; Mazza, Débora Dutra da Silveira; Dragosavac, Desanka; Toledo, Diogo Oliveira; Costa, Eduardo Leite; Caser, Eliana Bernardete; Silva, Eliezer; Amorim, Fabio Ferreira; Saddy, Felipe; Galas, Filomena Regina Barbosa Gomes; Silva, Gisele Sampaio; de Matos, Gustavo Faissol Janot; Emmerich, João Claudio; Valiatti, Jorge Luis dos Santos; Teles, José Mario Meira; Victorino, Josué Almeida; Ferreira, Juliana Carvalho; Prodomo, Luciana Passuello do Vale; Hajjar, Ludhmila Abrahão; Martins, Luiz Cláudio; Malbouisson, Luiz Marcelo Sá; Vargas, Mara Ambrosina de Oliveira; Reis, Marco Antonio Soares; Amato, Marcelo Brito Passos; Holanda, Marcelo Alcântara; Park, Marcelo; Jacomelli, Marcia; Tavares, Marcos; Damasceno, Marta Cristina Paulette; Assunção, Murillo Santucci César; Damasceno, Moyzes Pinto Coelho Duarte; Youssef, Nazah Cherif Mohamad; Teixeira, Paulo José Zimmermann; Caruso, Pedro; Duarte, Péricles Almeida Delfino; Messeder, Octavio; Eid, Raquel Caserta; Rodrigues, Ricardo Goulart; de Jesus, Rodrigo Francisco; Kairalla, Ronaldo Adib; Justino, Sandra; Nemer, Sérgio Nogueira; Romero, Simone Barbosa; Amado, Verônica Moreira

    2014-01-01

    Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document. PMID:25028944

  10. Brazilian recommendations of mechanical ventilation 2013. Part I.

    PubMed

    Barbas, Carmen Sílvia Valente; Isola, Alexandre Marini; Farias, Augusto Manoel de Carvalho; Cavalcanti, Alexandre Biasi; Gama, Ana Maria Casati; Duarte, Antonio Carlos Magalhães; Vianna, Arthur; Serpa Neto, Ary; Bravim, Bruno de Arruda; Pinheiro, Bruno do Valle; Mazza, Bruno Franco; Carvalho, Carlos Roberto Ribeiro de; Toufen Júnior, Carlos; David, Cid Marcos Nascimento; Taniguchi, Corine; Mazza, Débora Dutra da Silveira; Dragosavac, Desanka; Toledo, Diogo Oliveira; Costa, Eduardo Leite; Caser, Eliana Bernardete; Silva, Eliezer; Amorim, Fabio Ferreira; Saddy, Felipe; Galas, Filomena Regina Barbosa Gomes; Silva, Gisele Sampaio; Matos, Gustavo Faissol Janot de; Emmerich, João Claudio; Valiatti, Jorge Luis Dos Santos; Teles, José Mario Meira; Victorino, Josué Almeida; Ferreira, Juliana Carvalho; Prodomo, Luciana Passuello do Vale; Hajjar, Ludhmila Abrahão; Martins, Luiz Cláudio; Malbouisson, Luiz Marcelo Sá; Vargas, Mara Ambrosina de Oliveira; Reis, Marco Antonio Soares; Amato, Marcelo Brito Passos; Holanda, Marcelo Alcântara; Park, Marcelo; Jacomelli, Marcia; Tavares, Marcos; Damasceno, Marta Cristina Paulette; Assunção, Murillo Santucci César; Damasceno, Moyzes Pinto Coelho Duarte; Youssef, Nazah Cherif Mohamad; Teixeira, Paulo José Zimmermann; Caruso, Pedro; Duarte, Péricles Almeida Delfino; Messeder, Octavio; Eid, Raquel Caserta; Rodrigues, Ricardo Goulart; Jesus, Rodrigo Francisco de; Kairalla, Ronaldo Adib; Justino, Sandra; Nemer, Sérgio Nogueira; Romero, Simone Barbosa; Amado, Verônica Moreira

    2014-01-01

    Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumonia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document.

  11. Brazilian recommendations of mechanical ventilation 2013. Part I.

    PubMed

    2014-01-01

    Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document.

  12. Brazilian recommendations of mechanical ventilation 2013. Part 2.

    PubMed

    Barbas, Carmen Sílvia Valente; Ísola, Alexandre Marini; Farias, Augusto Manoel de Carvalho; Cavalcanti, Alexandre Biasi; Gama, Ana Maria Casati; Duarte, Antonio Carlos Magalhães; Vianna, Arthur; Serpa Neto, Ary; Bravim, Bruno de Arruda; Pinheiro, Bruno do Valle; Mazza, Bruno Franco; de Carvalho, Carlos Roberto Ribeiro; Toufen Júnior, Carlos; David, Cid Marcos Nascimento; Taniguchi, Corine; Mazza, Débora Dutra da Silveira; Dragosavac, Desanka; Toledo, Diogo Oliveira; Costa, Eduardo Leite; Caser, Eliana Bernadete; Silva, Eliezer; Amorim, Fabio Ferreira; Saddy, Felipe; Galas, Filomena Regina Barbosa Gomes; Silva, Gisele Sampaio; de Matos, Gustavo Faissol Janot; Emmerich, João Claudio; Valiatti, Jorge Luis dos Santos; Teles, José Mario Meira; Victorino, Josué Almeida; Ferreira, Juliana Carvalho; Prodomo, Luciana Passuello do Vale; Hajjar, Ludhmila Abrahão; Martins, Luiz Claudio; Malbouisson, Luis Marcelo Sá; Vargas, Mara Ambrosina de Oliveira; Reis, Marco Antonio Soares; Amato, Marcelo Brito Passos; Holanda, Marcelo Alcântara; Park, Marcelo; Jacomelli, Marcia; Tavares, Marcos; Damasceno, Marta Cristina Paulette; Assunção, Murillo Santucci César; Damasceno, Moyzes Pinto Coelho Duarte; Youssef, Nazah Cherif Mohamed; Teixeira, Paulo José Zimmermann; Caruso, Pedro; Duarte, Péricles Almeida Delfino; Messeder, Octavio; Eid, Raquel Caserta; Rodrigues, Ricardo Goulart; de Jesus, Rodrigo Francisco; Kairalla, Ronaldo Adib; Justino, Sandra; Nemer, Sergio Nogueira; Romero, Simone Barbosa; Amado, Verônica Moreira

    2014-01-01

    Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document.

  13. Brazilian recommendations of mechanical ventilation 2013. Part I

    PubMed Central

    2014-01-01

    Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document. PMID:25210957

  14. Brazilian recommendations of mechanical ventilation 2013. Part 2

    PubMed Central

    2014-01-01

    Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document. PMID:25410835

  15. Brazilian recommendations of mechanical ventilation 2013. Part 2

    PubMed Central

    Barbas, Carmen Sílvia Valente; Ísola, Alexandre Marini; Farias, Augusto Manoel de Carvalho; Cavalcanti, Alexandre Biasi; Gama, Ana Maria Casati; Duarte, Antonio Carlos Magalhães; Vianna, Arthur; Serpa Neto, Ary; Bravim, Bruno de Arruda; Pinheiro, Bruno do Valle; Mazza, Bruno Franco; de Carvalho, Carlos Roberto Ribeiro; Toufen Júnior, Carlos; David, Cid Marcos Nascimento; Taniguchi, Corine; Mazza, Débora Dutra da Silveira; Dragosavac, Desanka; Toledo, Diogo Oliveira; Costa, Eduardo Leite; Caser, Eliana Bernadete; Silva, Eliezer; Amorim, Fabio Ferreira; Saddy, Felipe; Galas, Filomena Regina Barbosa Gomes; Silva, Gisele Sampaio; de Matos, Gustavo Faissol Janot; Emmerich, João Claudio; Valiatti, Jorge Luis dos Santos; Teles, José Mario Meira; Victorino, Josué Almeida; Ferreira, Juliana Carvalho; Prodomo, Luciana Passuello do Vale; Hajjar, Ludhmila Abrahão; Martins, Luiz Claudio; Malbouisson, Luis Marcelo Sá; Vargas, Mara Ambrosina de Oliveira; Reis, Marco Antonio Soares; Amato, Marcelo Brito Passos; Holanda, Marcelo Alcântara; Park, Marcelo; Jacomelli, Marcia; Tavares, Marcos; Damasceno, Marta Cristina Paulette; Assunção, Murillo Santucci César; Damasceno, Moyzes Pinto Coelho Duarte; Youssef, Nazah Cherif Mohamed; Teixeira, Paulo José Zimmermann; Caruso, Pedro; Duarte, Péricles Almeida Delfino; Messeder, Octavio; Eid, Raquel Caserta; Rodrigues, Ricardo Goulart; de Jesus, Rodrigo Francisco; Kairalla, Ronaldo Adib; Justino, Sandra; Nemer, Sergio Nogueira; Romero, Simone Barbosa; Amado, Verônica Moreira

    2014-01-01

    Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document. PMID:25295817

  16. State of the evidence: mechanical ventilation with PEEP in patients with cardiogenic shock.

    PubMed

    Wiesen, Jonathan; Ornstein, Moshe; Tonelli, Adriano R; Menon, Venu; Ashton, Rendell W

    2013-12-01

    The need to provide invasive mechanical ventilatory support to patients with myocardial infarction and acute left heart failure is common. Despite the large number of patients requiring mechanical ventilation in this setting, there are remarkably few data addressing the ideal mode of respiratory support in such patients. Although there is near universal acceptance regarding the use of non-invasive positive pressure ventilation in patients with acute pulmonary oedema, there is more concern with invasive positive pressure ventilation owing to its more significant haemodynamic impact. Positive end-expiratory pressure (PEEP) is almost universally applied in mechanically ventilated patients due to benefits in gas exchange, recruitment of alveolar units, counterbalance of hydrostatic forces leading to pulmonary oedema and maintenance of airway patency. The limited available clinical data suggest that a moderate level of PEEP is safe to use in severe left ventricular (LV) dysfunction and cardiogenic shock, and may provide haemodynamic benefits as well in LV failure which exhibits afterload-sensitive physiology.

  17. Early Mobilization of Mechanically Ventilated Patients.

    PubMed

    Hruska, Pam

    2016-12-01

    Critically ill patients requiring mechanical ventilation are least likely to be mobilized and, as a result, are at-risk for prolonged complications from weakness. The use of bed rest and sedation when caring for mechanically ventilated patients is likely shaped by historical practice; however, this review demonstrates early mobilization, with little to no sedation, is possible and safe. Assessing readiness for mobilization in context of progressing patients from passive to active activities can lead to long-term benefits and has been achievable with resource-efficient implementations and team work.

  18. Non-invasive ventilation in amyotrophic lateral sclerosis.

    PubMed

    Vrijsen, Bart; Testelmans, Dries; Belge, Catharina; Robberecht, Wim; Van Damme, Philip; Buyse, Bertien

    2013-03-01

    Abstract Non-invasive ventilation (NIV) is widely used to improve alveolar hypoventilation in amyotrophic lateral sclerosis. Several studies indicate a better survival when NIV is used, certainly in patients with none to moderate bulbar dysfunction. Data on quality of life (QoL) are rather disputable. Overall QoL is shown to be equivalent in patients with or without NIV, although health-related QoL is shown to be increased in patients with none to moderate bulbar dysfunction. NIV improves sleep quality, although patient-ventilator asynchronies are demonstrated. FVC < 50%, seated or supine, has been widely applied as threshold to initiate NIV. Today, measurements of respiratory muscle strength, nocturnal gas exchange and symptomatic complaints are used as indicators to start NIV. Being compliant with NIV therapy increases QoL and survival. Cough augmentation has an important role in appropriate NIV. Patients have today more technical options and patients with benefit from these advances are growing in number. Tracheal ventilation needs to be discussed when NIV seems impossible or becomes insufficient.

  19. Flow measurement in mechanical ventilation: a review.

    PubMed

    Schena, Emiliano; Massaroni, Carlo; Saccomandi, Paola; Cecchini, Stefano

    2015-03-01

    Accurate monitoring of flow rate and volume exchanges is essential to minimize ventilator-induced lung injury. Mechanical ventilators employ flowmeters to estimate the amount of gases delivered to patients and use the flow signal as a feedback to adjust the desired amount of gas to be delivered. Since flowmeters play a crucial role in this field, they are required to fulfill strict criteria in terms of dynamic and static characteristics. Therefore, mechanical ventilators are equipped with only the following kinds of flowmeters: linear pneumotachographs, fixed and variable orifice meters, hot wire anemometers, and ultrasonic flowmeters. This paper provides an overview of these sensors. Their working principles are described together with their relevant advantages and disadvantages. Furthermore, the most promising emerging approaches for flowmeters design (i.e., fiber optic technology and three dimensional micro-fabrication) are briefly reviewed showing their potential for this application.

  20. Mechanical Ventilation in Sepsis: A Reappraisal.

    PubMed

    Zampieri, Fernando G; Mazza, Bruno

    2017-01-01

    Sepsis is the main cause of close to 70% of all cases of acute respiratory distress syndromes (ARDS). In addition, sepsis increases susceptibility to ventilator-induced lung injury. Therefore, the development of a ventilatory strategy that can achieve adequate oxygenation without injuring the lungs is highly sought after for patients with acute infection and represents an important therapeutic window to improve patient care. Suboptimal ventilatory settings cannot only harm the lung, but may also contribute to the cascade of organ failure in sepsis due to organ crosstalk.Despite the prominent role of sepsis as a cause for lung injury, most of the studies that addressed mechanical ventilation strategies in ARDS did not specifically assess sepsis-related ARDS patients. Consequently, most of the recommendations regarding mechanical ventilation in sepsis patients are derived from ARDS trials that included multiple clinical diagnoses. While there have been important improvements in general ventilatory management that should apply to all critically ill patients, sepsis-related lung injury might still have particularities that could influence bedside management.After revisiting the interplay between sepsis and ventilation-induced lung injury, this review will reappraise the evidence for the major components of the lung protective ventilation strategy, emphasizing the particularities of sepsis-related acute lung injury.

  1. Early non-invasive ventilation treatment for severe influenza pneumonia.

    PubMed

    Masclans, J R; Pérez, M; Almirall, J; Lorente, L; Marqués, A; Socias, L; Vidaur, L; Rello, J

    2013-03-01

    The role of non-invasive ventilation (NIV) in acute respiratory failure caused by viral pneumonia remains controversial. Our objective was to evaluate the use of NIV in a cohort of (H1N1)v pneumonia. Usefulness and success of NIV were assessed in a prospective, observational registry of patients with influenza A (H1N1) virus pneumonia in 148 Spanish intensive care units (ICUs) in 2009-10. Significant variables for NIV success were included in a multivariate analysis. In all, 685 patients with confirmed influenza A (H1N1)v viral pneumonia were admitted to participating ICUs; 489 were ventilated, 177 with NIV. The NIV was successful in 72 patients (40.7%), the rest required intubation. Low Acute Physiology and Chronic Health Evaluation (APACHE) II, low Sequential Organ Failure Assessment (SOFA) and absence of renal failure were associated with NIV success. Success of NIV was independently associated with fewer than two chest X-ray quadrant opacities (OR 3.5) and no vasopressor requirement (OR 8.1). However, among patients with two or more quadrant opacities, a SOFA score ≤7 presented a higher success rate than those with SOFA score >7 (OR 10.7). Patients in whom NIV was successful required shorter ventilation time, shorter ICU stay and hospital stay than NIV failure. In patients in whom NIV failed, the delay in intubation did not increase mortality (26.5% versus 24.2%). Clinicians used NIV in 25.8% of influenza A (H1N1)v viral pneumonia admitted to ICU, and treatment was effective in 40.6% of them. NIV success was associated with shorter hospital stay and mortality similar to non-ventilated patients. NIV failure was associated with a mortality similar to those who were intubated from the start.

  2. A Medical Student Workshop in Mechanical Ventilation.

    ERIC Educational Resources Information Center

    And Others; Kushins, Lawrence G.

    1980-01-01

    In order to teach applied respiratory physiology to medical students, the anesthesiology faculty at the University of Florida College of Medicine has designed and implemented a course that includes a laboratory workshop in mechanical ventilation of an animal model that allows students to apply and expand their knowledge. (JMD)

  3. Special cases: mechanical ventilation of neurosurgical patients.

    PubMed

    Johnson, Victoria E; Huang, Jason H; Pilcher, Webster H

    2007-04-01

    Mechanical ventilation has evolved greatly over the last half century, guided primarily by improved comprehension of the relevant pathology/physiology. Neurosurgical patients are a unique subgroup of patients who heavily use this technology for both support, and less commonly, as a therapy. Such patients demand special consideration with regard to mode of ventilation, use of positive end-expiratory pressure, and monitoring. In addition, meeting the ventilatory needs of neurosurgical patients while minimizing ventilatory-induced lung damage can be a challenging aspect of care.

  4. Complementary home mechanical ventilation techniques. SEPAR Year 2014.

    PubMed

    Chiner, Eusebi; Sancho-Chust, José N; Landete, Pedro; Senent, Cristina; Gómez-Merino, Elia

    2014-12-01

    This is a review of the different complementary techniques that are useful for optimizing home mechanical ventilation (HMV). Airway clearance is very important in patients with HMV and many patients, particularly those with reduced peak cough flow, require airway clearance (manual or assisted) or assisted cough techniques (manual or mechanical) and suctioning procedures, in addition to ventilation. In the case of invasive HMV, good tracheostomy cannula management is essential for success. HMV patients may have sleep disturbances that must be taken into account. Sleep studies including complete polysomnography or respiratory polygraphy are helpful for identifying patient-ventilator asynchrony. Other techniques, such as bronchoscopy or nutritional support, may be required in patients on HMV, particularly if percutaneous gastrostomy is required. Information on treatment efficacy can be obtained from HMV monitoring, using methods such as pulse oximetry, capnography or the internal programs of the ventilators themselves. Finally, the importance of the patient's subjective perception is reviewed, as this may potentially affect the success of the HMV.

  5. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Each exhaust type mechanical ventilation system required under § 154.1200 (a) must have ducts for... duct under paragraph (a) of this section must be at least 10 m (32.8 ft.) from ventilation intakes and... operational controls outside the ventilated space. (g) No ventilation duct for a gas-dangerous space may...

  6. Assessment of mechanical ventilation parameters on respiratory mechanics.

    PubMed

    Pidaparti, Ramana M; Koombua, Kittisak; Ward, Kevin R

    2012-01-01

    Better understanding of airway mechanics is very important in order to avoid lung injuries for patients undergoing mechanical ventilation for treatment of respiratory problems in intensive-care medicine, as well as pulmonary medicine. Mechanical ventilation depends on several parameters, all of which affect the patient outcome. As there are no systematic numerical investigations of the role of mechanical ventilation parameters on airway mechanics, the objective of this study was to investigate the role of mechanical ventilation parameters on airway mechanics using coupled fluid-solid computational analysis. For the airway geometry of 3 to 5 generations considered, the simulation results showed that airflow velocity increased with increasing airflow rate. Airway pressure increased with increasing airflow rate, tidal volume and positive end-expiratory pressure (PEEP). Airway displacement and airway strains increased with increasing airflow rate, tidal volume and PEEP form mechanical ventilation. Among various waveforms considered, sine waveform provided the highest airflow velocity and airway pressure while descending waveform provided the lowest airway pressure, airway displacement and airway strains. These results combined with optimization suggest that it is possible to obtain a set of mechanical ventilation strategies to avoid lung injuries in patients.

  7. [Monitorization of respiratory mechanics in the ventilated patient].

    PubMed

    García-Prieto, E; Amado-Rodríguez, L; Albaiceta, G M

    2014-01-01

    Monitoring during mechanical ventilation allows the measurement of different parameters of respiratory mechanics. Accurate interpretation of these data can be useful for characterizing the situation of the different components of the respiratory system, and for guiding ventilator settings. In this review, we describe the basic concepts of respiratory mechanics, their interpretation, and their potential use in fine-tuning mechanical ventilation.

  8. Mechanical ventilation for status asthmaticus in children.

    PubMed

    Dworkin, G; Kattan, M

    1989-04-01

    We retrospectively reviewed the time course of recovery of pediatric patients in status asthmaticus who were undergoing mechanical ventilation for life-threatening respiratory failure to evaluate the results with current medications and technology. Ten patients between 2 and 18 years of age underwent intubation on 20 occasions. Mechanical ventilation was maintained for a mean of 2 days. Positive end-expiratory pressure was introduced in the recovery phase to prevent hypoxemia. Twelve episodes (Group 1) involved intubation less than 48 hours; in eight episodes (group 2) the patients required ventilatory support greater than 48 hours. The two groups did not differ in regard to age, pharmacologic therapy, preintubation arterial blood gas data, or initial ventilator settings, but the rise in pH and fall in Paco2 differed significantly over the first 12 hours of therapy. In the group 2 patients, peak pressures were not increased greater than 60 cm H2O despite elevated Paco2 values, and aggressive sodium bicarbonate therapy for pH correction was not pursued. Complications were few and all patients survived. We conclude that asthma patients have variable resolution of airway obstruction during mechanical ventilation and that controlled hypoventilation can be a safe therapy for the patients with more severe obstruction.

  9. [Principles and function of mechanical ventilation: classification and modes of ventilators].

    PubMed

    Kelbel, C; Huntemann, M; Lorenz, J

    2006-04-01

    A spectrum of diseases is associated with the necessity for partial or total support of pulmonary ventilation. The insight into the function of ventilators and their modes reduces the spectrum of ventilatory support to a few basic principles. The knowledge enables the pulmonary intensivist to adapt mechanical ventilation to the individual patient's needs. This overview describes the technical aspects of mechanical ventilation and summarizes the variety of specific modes implied.

  10. History of Mechanical Ventilation. From Vesalius to Ventilator-induced Lung Injury.

    PubMed

    Slutsky, Arthur S

    2015-05-15

    Mechanical ventilation is a life-saving therapy that catalyzed the development of modern intensive care units. The origins of modern mechanical ventilation can be traced back about five centuries to the seminal work of Andreas Vesalius. This article is a short history of mechanical ventilation, tracing its origins over the centuries to the present day. One of the great advances in ventilatory support over the past few decades has been the development of lung-protective ventilatory strategies, based on our understanding of the iatrogenic consequences of mechanical ventilation such as ventilator-induced lung injury. These strategies have markedly improved clinical outcomes in patients with respiratory failure.

  11. Effective sample size estimation for a mechanical ventilation trial through Monte-Carlo simulation: Length of mechanical ventilation and Ventilator Free Days.

    PubMed

    Morton, S E; Chiew, Y S; Pretty, C; Moltchanova, E; Scarrott, C; Redmond, D; Shaw, G M; Chase, J G

    2017-02-01

    Randomised control trials have sought to seek to improve mechanical ventilation treatment. However, few trials to date have shown clinical significance. It is hypothesised that aside from effective treatment, the outcome metrics and sample sizes of the trial also affect the significance, and thus impact trial design. In this study, a Monte-Carlo simulation method was developed and used to investigate several outcome metrics of ventilation treatment, including 1) length of mechanical ventilation (LoMV); 2) Ventilator Free Days (VFD); and 3) LoMV-28, a combination of the other metrics. As these metrics have highly skewed distributions, it also investigated the impact of imposing clinically relevant exclusion criteria on study power to enable better design for significance. Data from invasively ventilated patients from a single intensive care unit were used in this analysis to demonstrate the method. Use of LoMV as an outcome metric required 160 patients/arm to reach 80% power with a clinically expected intervention difference of 25% LoMV if clinically relevant exclusion criteria were applied to the cohort, but 400 patients/arm if they were not. However, only 130 patients/arm would be required for the same statistical significance at the same intervention difference if VFD was used. A Monte-Carlo simulation approach using local cohort data combined with objective patient selection criteria can yield better design of ventilation studies to desired power and significance, with fewer patients per arm than traditional trial design methods, which in turn reduces patient risk. Outcome metrics, such as VFD, should be used when a difference in mortality is also expected between the two cohorts. Finally, the non-parametric approach taken is readily generalisable to a range of trial types where outcome data is similarly skewed.

  12. Home mechanical ventilation: a Canadian Thoracic Society clinical practice guideline.

    PubMed

    McKim, Douglas A; Road, Jeremy; Avendano, Monica; Abdool, Steve; Cote, Fabien; Duguid, Nigel; Fraser, Janet; Maltais, Fracois; Morrison, Debra L; O'Connell, Colleen; Petrof, Basil J; Rimmer, Karen; Skomro, Robert

    2011-01-01

    Increasing numbers of patients are surviving episodes of prolonged mechanical ventilation or benefitting from the recent availability of userfriendly noninvasive ventilators. Although many publications pertaining to specific aspects of home mechanical ventilation (HMV) exist, very few comprehensive guidelines that bring together all of the current literature on patients at risk for or using mechanical ventilatory support are available. The Canadian Thoracic Society HMV Guideline Committee has reviewed the available English literature on topics related to HMV in adults, and completed a detailed guideline that will help standardize and improve the assessment and management of individuals requiring noninvasive or invasive HMV. The guideline provides a disease-specific review of illnesses including amyotrophic lateral sclerosis, spinal cord injury, muscular dystrophies, myotonic dystrophy, kyphoscoliosis, post-polio syndrome, central hypoventilation syndrome, obesity hypoventilation syndrome, and chronic obstructive pulmonary disease as well as important common themes such as airway clearance and the process of transition to home. The guidelines have been extensively reviewed by international experts, allied health professionals and target audiences. They will be updated on a regular basis to incorporate any new information.

  13. Respiratory infections in patients undergoing mechanical ventilation.

    PubMed

    Rello, Jordi; Lisboa, Thiago; Koulenti, Despoina

    2014-09-01

    Lower respiratory tract infections in mechanically ventilated patients are a frequent cause of antibiotic treatment in intensive-care units. These infections present as severe sepsis or septic shock with respiratory dysfunction in intubated patients. Purulent respiratory secretions are needed for diagnosis, but distinguishing between pneumonia and tracheobronchitis is not easy. Both presentations are associated with longlasting mechanical ventilation and extended intensive-care unit stay, providing a rationale for antibiotic treatment initiation. Differentiation of colonisers from true pathogens is difficult, and microbiological data show Staphylococcus aureus and Pseudomonas aeruginosa to be of great concern because of clinical outcomes and therapeutic challenges. Key management issues include identification of the pathogen, choice of initial empirical antibiotic, and decisions with regard to the resolution pattern.

  14. Bilateral Scapulohumeral Ankylosis after Prolonged Mechanical Ventilation

    PubMed Central

    Schreinemakers, J. Rieneke; van Noort, Arthur; Rademakers, Maarten V.

    2016-01-01

    This case demonstrates a rarely reported bilateral scapulohumeral bony ankylosis. A young woman developed extensive heterotopic ossifications (HOs) in both shoulder joints after being mechanically ventilated for several months at the intensive care unit in a comatose status. She presented with a severe movement restriction of both shoulder joints. Surgical resection of the bony bridges was performed in 2 separate sessions with a significant improvement of shoulder function afterwards. No postoperative complications, pain, or recurrence of HOs were noted at 1-year follow-up. Mechanical ventilation, immobilization, neuromuscular blockage, and prolonged sedation are known risk factors for the development of HOs in the shoulder joints. Relatively early surgical resection of the HOs can be performed safely in contrary to earlier belief. Afterwards, nonsteroidal anti-inflammatory drugs and/or radiation therapy can be possible treatment modalities to prevent recurrence of HOs. PMID:27583120

  15. Patient-ventilator asynchronies: may the respiratory mechanics play a role?

    PubMed Central

    2013-01-01

    Introduction The mechanisms leading to patient/ventilator asynchrony has never been systematically assessed. We studied the possible association between asynchrony and respiratory mechanics in patients ready to be enrolled for a home non-invasive ventilatory program. Secondarily, we looked for possible differences in the amount of asynchronies between obstructive and restrictive patients and a possible role of asynchrony in influencing the tolerance of non-invasive ventilation (NIV). Methods The respiratory pattern and mechanics of 69 consecutive patients with chronic respiratory failure were recorded during spontaneous breathing. After that patients underwent non-invasive ventilation for 60 minutes with a "dedicated" NIV platform in a pressure support mode during the day. In the last 15 minutes of this period, asynchrony events were detected and classified as ineffective effort (IE), double triggering (DT) and auto-triggering (AT). Results The overall number of asynchronies was not influenced by any variable of respiratory mechanics or by the underlying pathologies (that is, obstructive vs restrictive patients). There was a high prevalence of asynchrony events (58% of patients). IEs were the most frequent asynchronous events (45% of patients) and were associated with a higher level of pressure support. A high incidence of asynchrony events and IE were associated with a poor tolerance of NIV. Conclusions Our study suggests that in non-invasively ventilated patients for a chronic respiratory failure, the incidence of patient-ventilator asynchronies was relatively high, but did not correlate with any parameters of respiratory mechanics or underlying disease. PMID:23531269

  16. Collective fluid mechanics of honeybee nest ventilation

    NASA Astrophysics Data System (ADS)

    Gravish, Nick; Combes, Stacey; Wood, Robert J.; Peters, Jacob

    2014-11-01

    Honeybees thermoregulate their brood in the warm summer months by collectively fanning their wings and creating air flow through the nest. During nest ventilation workers flap their wings in close proximity in which wings continuously operate in unsteady oncoming flows (i.e. the wake of neighboring worker bees) and near the ground. The fluid mechanics of this collective aerodynamic phenomena are unstudied and may play an important role in the physiology of colony life. We have performed field and laboratory observations of the nest ventilation wing kinematics and air flow generated by individuals and groups of honeybee workers. Inspired from these field observations we describe here a robotic model system to study collective flapping wing aerodynamics. We microfabricate arrays of 1.4 cm long flapping wings and observe the air flow generated by arrays of two or more fanning robotic wings. We vary phase, frequency, and separation distance among wings and find that net output flow is enhanced when wings operate at the appropriate phase-distance relationship to catch shed vortices from neighboring wings. These results suggest that by varying position within the fanning array honeybee workers may benefit from collective aerodynamic interactions during nest ventilation.

  17. Estimates of the demand for mechanical ventilation in the US during an influenza pandemic

    PubMed Central

    Meltzer, Martin I.; Patel, Anita; Koonin, Lisa M.

    2015-01-01

    An outbreak in China in April 2013 of human illnesses due to avian influenza A(H7N9) virus provided reason for U.S. public health officials to revisit existing national pandemic response plans. We built a spreadsheet model to examine the potential demand for invasive mechanical ventilation (excluding “rescue therapy" ventilation). We considered scenarios of either 20% or 30% gross influenza clinical attack rate (CAR), with a “low severity” scenario with case fatality rates (CFR) of 0.05%–0.1%, or a “high severity” scenario (CFR: 0.25%–0.5%). We used rates-of-influenza-related illness to calculate the numbers of potential clinical cases, hospitalizations, admissions to intensive care units (ICUs), and need for mechanical ventilation. We assumed 10 days ventilator use per ventilated patient, 13% of total ventilator demand will occur at peak, and a 33.7% weighted average mortality risk while on a ventilator. At peak, for a 20% CAR, low severity scenario, an additional 7,000 to 11,000 ventilators will be needed, averting a pandemic total of 35,000 to 55,000 deaths. A 30% CAR, high severity scenario, will need approximately 35,000 to 60,500 additional ventilators, averting a pandemic total 178,000 to 308,000 deaths. Estimates of deaths averted may not be realized because successful ventilation also depends on sufficient numbers of suitably trained staff, needed supplies (e.g., drugs, reliable oxygen sources, suction apparatus, circuits, and monitoring equipment) and timely ability to match access to ventilators with critically ill cases. There is a clear challenge to plan and prepare to meet demands for mechanical ventilators for a future severe pandemic. PMID:25878301

  18. Estimates of the demand for mechanical ventilation in the United States during an influenza pandemic.

    PubMed

    Meltzer, Martin I; Patel, Anita; Ajao, Adebola; Nystrom, Scott V; Koonin, Lisa M

    2015-05-01

    An outbreak in China in April 2013 of human illnesses due to avian influenza A(H7N9) virus provided reason for US public health officials to revisit existing national pandemic response plans. We built a spreadsheet model to examine the potential demand for invasive mechanical ventilation (excluding "rescue therapy" ventilation). We considered scenarios of either 20% or 30% gross influenza clinical attack rate (CAR), with a "low severity" scenario with case fatality rates (CFR) of 0.05%-0.1%, or a "high severity" scenario (CFR: 0.25%-0.5%). We used rates-of-influenza-related illness to calculate the numbers of potential clinical cases, hospitalizations, admissions to intensive care units, and need for mechanical ventilation. We assumed 10 days ventilator use per ventilated patient, 13% of total ventilator demand will occur at peak, and a 33.7% weighted average mortality risk while on a ventilator. At peak, for a 20% CAR, low severity scenario, an additional 7000 to 11,000 ventilators will be needed, averting a pandemic total of 35,000 to 55,000 deaths. A 30% CAR, high severity scenario, will need approximately 35,000 to 60,500 additional ventilators, averting a pandemic total 178,000 to 308,000 deaths. Estimates of deaths averted may not be realized because successful ventilation also depends on sufficient numbers of suitably trained staff, needed supplies (eg, drugs, reliable oxygen sources, suction apparatus, circuits, and monitoring equipment) and timely ability to match access to ventilators with critically ill cases. There is a clear challenge to plan and prepare to meet demands for mechanical ventilators for a future severe pandemic.

  19. The influence of music during mechanical ventilation and weaning from mechanical ventilation: A review.

    PubMed

    Hetland, Breanna; Lindquist, Ruth; Chlan, Linda L

    2015-01-01

    Mechanical ventilation (MV) causes many distressing symptoms. Weaning, the gradual decrease in ventilator assistance leading to termination of MV, increases respiratory effort, which may exacerbate symptoms and prolong MV. Music, a non-pharmacological intervention without side effects may benefit patients during weaning from mechanical ventilatory support. A narrative review of OVID Medline, PsychINFO, and CINAHL databases was conducted to examine the evidence for the use of music intervention in MV and MV weaning. Music intervention had a positive impact on ventilated patients; 16 quantitative and 2 qualitative studies were identified. Quantitative studies included randomized clinical trials (10), case controls (3), pilot studies (2) and a feasibility study. Evidence supports music as an effective intervention that can lesson symptoms related to MV and promote effective weaning. It has potential to reduce costs and increase patient satisfaction. However, more studies are needed to establish its use during MV weaning.

  20. Design Features of Modern Mechanical Ventilators.

    PubMed

    MacIntyre, Neil

    2016-12-01

    A positive-pressure breath ideally should provide a VT that is adequate for gas exchange and appropriate muscle unloading while minimizing any risk for injury or discomfort. The latest generation of ventilators uses sophisticated feedback systems to sculpt positive-pressure breaths according to patient effort and respiratory system mechanics. Currently, however, these new control strategies are not totally closed-loop systems. This is because the automatic input variables remain limited, some clinician settings are still required, and the specific features of the perfect breath design still are not entirely clear. Despite these limitations, there are some rationale for many of these newer feedback features.

  1. The Therapeutic Outcomes of Mechanical Ventilation in Hematological Malignancy Patients with Respiratory Failure.

    PubMed

    Fujiwara, Yusuke; Yamaguchi, Hiroki; Kobayashi, Katsuya; Marumo, Atsushi; Omori, Ikuko; Yamanaka, Satoshi; Yui, Shunsuke; Fukunaga, Keiko; Ryotokuji, Takeshi; Hirakawa, Tsuneaki; Okabe, Masahiro; Wakita, Satoshi; Tamai, Hayato; Okamoto, Muneo; Nakayama, Kazutaka; Takeda, Shinhiro; Inokuchi, Koiti

    2016-01-01

    Objective In hematological malignancy patients, the complication of acute respiratory failure often reaches a degree of severity that necessitates mechanical ventilation. The objective of the present study was to investigate the therapeutic outcomes of mechanical ventilation in hematological malignancy patients with respiratory failure and to analyze the factors that are associated with successful treatment in order to identify the issues that should be addressed in the future. Methods The present study was a retrospective analysis of 71 hematological malignancy patients with non-cardiogenic acute respiratory failure who were treated with mechanical ventilation at Nippon Medical School Hospital between 2003 and 2014. Results Twenty-six patients (36.6%) were treated with mechanical ventilation in an intensive care unit (ICU). Non-invasive positive pressure ventilation (NPPV) was applied in 29 cases (40.8%). The rate of successful mechanical ventilation treatment with NPPV alone was 13.8%. The rate of endotracheal extubation was 17.7%. A univariate analysis revealed that the following factors were associated with the successful extubation of patients who received invasive mechanical ventilation: respiratory management in an ICU (p=0.012); remission of the hematological disease (p=0.011); female gender (p=0.048); low levels of accompanying non-respiratory organ failure (p=0.041); and the non-use of extracorporeal circulation (p=0.005). A subsequent multivariate analysis revealed that respiratory management in an ICU was the only variable associated with successful extubation (p=0.030). Conclusion The outcomes of hematological malignancy patients who receive mechanical ventilation treatment for respiratory failure are very poor. Respiratory management in an ICU environment may be useful in improving the therapeutic outcomes of such patients.

  2. The growing role of noninvasive ventilation in patients requiring prolonged mechanical ventilation.

    PubMed

    Hess, Dean R

    2012-06-01

    For many patients with chronic respiratory failure requiring ventilator support, noninvasive ventilation (NIV) is preferable to invasive support by tracheostomy. Currently available evidence does not support the use of nocturnal NIV in unselected patients with stable COPD. Several European studies have reported benefit for high intensity NIV, in which setting of inspiratory pressure and respiratory rate are selected to achieve normocapnia. There have also been studies reporting benefit for the use of NIV as an adjunct to exercise training. NIV may be useful as an adjunct to airway clearance techniques in patients with cystic fibrosis. Accumulating evidence supports the use of NIV in patients with obesity hypoventilation syndrome. There is considerable observational evidence supporting the use of NIV in patients with chronic respiratory failure related to neuromuscular disease, and one randomized controlled trial reported that the use of NIV was life-prolonging in patients with amyotrophic lateral sclerosis. A variety of interfaces can be used to provide NIV in patients with stable chronic respiratory failure. The mouthpiece is an interface that is unique in this patient population, and has been used with success in patients with neuromuscular disease. Bi-level pressure ventilators are commonly used for NIV, although there are now a new generation of intermediate ventilators that are portable, have a long battery life, and can be used for NIV and invasive applications. Pressure support ventilation, pressure controlled ventilation, and volume controlled ventilation have been used successfully for chronic applications of NIV. New modes have recently become available, but their benefits await evidence to support their widespread use. The success of NIV in a given patient population depends on selection of an appropriate patient, selection of an appropriate interface, selection of an appropriate ventilator and ventilator settings, the skills of the clinician, the

  3. Nutritional support of the mechanically ventilated patient.

    PubMed

    Shikora, S A; Benotti, P N

    1997-03-01

    As with all critically ill patients, those requiring mechanical ventilation are susceptible to the wasting of illness and cannot survive without prompt nutritional support. It may be fair to say that the proper provision of nutrients, and in particular the avoidance of overfeeding, are even more crucial for this subset of critically ill patients. To maximize the overall benefits of feeding, it is crucial to provide the nutritional support early and enterally whenever possible. Therefore, the best strategy for early removal of the mechanical ventilatory support must include the timely and careful administration of nutrients, micronutrients, minerals, vitamins, and fluid, in conjunction with standard intensive care therapeutics and the appropriate respiratory muscle-strengthening program.

  4. Ofloxacin pharmacokinetics in mechanically ventilated patients.

    PubMed Central

    Martin, C; Lambert, D; Bruguerolle, B; Saux, P; Freney, J; Fleurette, J; Meugnier, H; Gouin, F

    1991-01-01

    The pharmacokinetics of ofloxacin were studied in 12 intensive care patients, 6 of whom were under controlled mechanical ventilation. All patients had a creatinine clearance of greater than 80 ml/min per 1.73 m2. They were given 3 mg of ofloxacin per kg of body weight intravenously at a constant flow rate in 30 min twice a day for 7 days. Pharmacokinetic studies were performed on days 1 and 7. Between days 1 and 7, significant increases in the alpha (distribution) and beta (elimination) phase half-lives, the area under the serum concentration-time curve, and peak and trough levels in serum were observed, together with a marked decrease (greater than 50%) in total body clearance. Possible contributing factors for alteration of ofloxacin pharmacokinetics in ventilated patients were patient age, liver dysfunction, drug interaction, and drug accumulation in a deep compartment. This study shows that in intensive care patients the pharmacokinetics of ofloxacin differ from those reported for healthy volunteers. PMID:1929329

  5. [Chronic respiratory insufficiency. Non-invasive long-term ventilation methods].

    PubMed

    Aubier, M; Muir, J F; Robert, D; Leger, P; Langevin, B; Benhamou, D

    1993-01-01

    The techniques of non-invasive ventilation have reappeared in force as an assortment of therapeutic techniques since the end of the 1980's. At the same time there was a transient renewed interest in perithoracic ventilation favouring the use of new methods of connection to the patient (e.g. poncho). The principal feature has been the use of intermittent positive pressure ventilation by the nasal route, which rapidly became essential for home therapy in patients with chronic restrictive respiratory failure notably in those secondary to thoracic deformation and to neuromuscular pathology. The concept of resting the respiratory muscles has been the basis for techniques of ventilatory assistance and in part the nasal route has now replaced home ventilation using a tracheotomy. Also in certain types of acute respiratory failure, nasal ventilation widely preferred over endotracheal ventilation.

  6. Review of ventilatory techniques to optimize mechanical ventilation in acute exacerbation of chronic obstructive pulmonary disease.

    PubMed

    Reddy, Raghu M; Guntupalli, Kalpalatha K

    2007-01-01

    Chronic obstructive pulmonary disease (COPD) is a major global healthcare problem. Studies vary widely in the reported frequency of mechanical ventilation in acute exacerbations of COPD. Invasive intubation and mechanical ventilation may be associated with significant morbidity and mortality. A good understanding of the airway pathophysiology and lung mechanics in COPD is necessary to appropriately manage acute exacerbations and respiratory failure. The basic pathophysiology in COPD exacerbation is the critical expiratory airflow limitation with consequent dynamic hyperinflation. These changes lead to further derangement in ventilatory mechanics, muscle function and gas exchange which may result in respiratory failure. This review discusses the altered respiratory mechanics in COPD, ways to detect these changes in a ventilated patient and formulating ventilatory techniques to optimize management of respiratory failure due to exacerbation of COPD.

  7. Review of ventilatory techniques to optimize mechanical ventilation in acute exacerbation of chronic obstructive pulmonary disease

    PubMed Central

    Reddy, Raghu M; Guntupalli, Kalpalatha K

    2007-01-01

    Chronic obstructive pulmonary disease (COPD) is a major global healthcare problem. Studies vary widely in the reported frequency of mechanical ventilation in acute exacerbations of COPD. Invasive intubation and mechanical ventilation may be associated with significant morbidity and mortality. A good understanding of the airway pathophysiology and lung mechanics in COPD is necessary to appropriately manage acute exacerbations and respiratory failure. The basic pathophysiology in COPD exacerbation is the critical expiratory airflow limitation with consequent dynamic hyperinflation. These changes lead to further derangement in ventilatory mechanics, muscle function and gas exchange which may result in respiratory failure. This review discusses the altered respiratory mechanics in COPD, ways to detect these changes in a ventilated patient and formulating ventilatory techniques to optimize management of respiratory failure due to exacerbation of COPD. PMID:18268918

  8. Non-invasive ventilation in acute respiratory failure in children

    PubMed Central

    Abadesso, Clara; Nunes, Pedro; Silvestre, Catarina; Matias, Ester; Loureiro, Helena; Almeida, Helena

    2012-01-01

    The aim of this paper is to assess the clinical efficacy of non-invasive ventilation (NIV) in avoiding endotracheal intubation (ETI), to demonstrate clinical and gasometric improvement and to identify predictive risk factors associated with NIV failure. An observational prospective clinical study was carried out. Included Patients with acute respiratory disease (ARD) treated with NIV, from November 2006 to January 2010 in a Pediatric Intensive Care Unit (PICU). NIV was used in 151 patients with acute respiratory failure (ARF). Patients were divided in two groups: NIV success and NIV failure, if ETI was required. Mean age was 7.2±20.3 months (median: 1 min: 0,3 max.: 156). Main diagnoses were bronchiolitis in 102 (67.5%), and pneumonia in 44 (29%) patients. There was a significant improvement in respiratory rate (RR), heart rate (HR), pH, and pCO2 at 2, 6, 12 and 24 hours after NIV onset (P<0.05) in both groups. Improvement in pulse oximetric saturation/fraction of inspired oxygen (SpO2/FiO2) was verified at 2, 4, 6, 12 and 24 hours after NIV onset in the success group (P<0.001). In the failure group, significant SpO2/FiO2 improvement was only observed in the first 4 hours. NIV failure occurred in 34 patients (22.5%). Risk factors for NIV failure were apnea, prematurity, pneumonia, and bacterial co-infection (P<0.05). Independent risk factors for NIV failure were apneia (P<0.001; odds ratio 15.8; 95% confidence interval: 3.42–71.4) and pneumonia (P<0.001, odds ratio 31.25; 95% confidence interval: 8.33–111.11). There were no major complications related with NIV. In conclusion this study demonstrates the efficacy of NIV as a form of respiratory support for children and infants with ARF, preventing clinical deterioration and avoiding ETI in most of the patients. Risk factors for failure were related with immaturity and severe infection. PMID:22802994

  9. Non-invasive determination of respiratory effort in spontaneous breathing and support ventilation: a validation study with healthy volunteers.

    PubMed

    Lopez-Navas, Kristel; Brandt, Sebastian; Strutz, Merle; Gehring, Hartmut; Wenkebach, Ullrich

    2014-08-01

    The proper setting of support ventilation aims to follow the patients' demands, ensuring adequate assistance to their respiratory effort. Effort assessment is thus necessary. But invasive procedures like measuring transdiaphragmatic pressure (Pdi) are impractical in long-term ventilation. Our purpose was therefore the development of the Occlusion+Delta (O+D) method for non-invasive continuous assessment of effort, quantified by the inspiratory pressure-time-product (PTPinsp), during ventilatory support. Flow and airway pressure were measured from 25 healthy volunteers at three effort levels. For the non-invasive method, short expiratory occlusions were executed each three to seven cycles to estimate resistance and compliance with a fitting algorithm fed with the differences between occluded and undisturbed cycles. Signals and estimates were then used to calculate the effort. For the validation of O+D, its estimations were compared to the results from invasive measurement of Pdi using balloon catheters. The agreement between PTPinsp from the invasive measurement and the proposed alternative was confirmed by regression analysis (PTP(O+D)=1.13PTP(Pdi)- 0.85, R²=0.84) and calculation of their differences (mean±SD=1.78±7.18 cm H2O s). Repeated execution of the non-invasive O+D method facilitates a safe automatic assessment of respiratory mechanics and breathing effort, promoting the rapid recognition of changes in patient's demands and the adaptation of support.

  10. Update on clinical trials in home mechanical ventilation.

    PubMed

    Hodgson, Luke E; Murphy, Patrick B

    2016-02-01

    Home mechanical ventilation (HMV) is an increasingly common intervention and is initiated for a range of pathological processes, including neuromuscular disease (NMD), chronic obstructive pulmonary disease (COPD) and obesity related respiratory failure. There have been important recent data published in this area, which helps to guide practice by indicating which populations may benefit from this intervention and the optimum method of setting up and controlling sleep disordered breathing. Recent superficially conflicting data has been published regarding HMV in COPD, with a trial in post-exacerbation patients suggesting no benefit, but in stable chronic hypercapnic patients suggesting a clear and sustained mortality benefit. The two studies are critiqued and the potential reasons for the differing results are discussed. Early and small trial data is frequently contradicted with larger randomised controlled trials and this has been the case with diaphragm pacing being shown to be potentially harmful in the latest data, confirming the importance of non-invasive ventilation (NIV) in NMD such as motor neurone disease. Advances in ventilator technology have so far appeared quicker than the clinical data to support their use; although small and often unblinded, the current data suggests equivalence to standard modes of NIV, but with potential comfort benefits that may enhance adherence. The indications for NIV have expanded since its inception, with an effort to treat sleep disordered breathing as a result of chronic heart failure (HF). The SERVE-HF trial has recently demonstrated no clear advantage to this technology and furthermore detected a potentially deleterious effect, with a worsening of all cause and cardiovascular mortality in the treated group compared to controls. The review serves to provide the reader with a critical review of recent advances in the field of sleep disordered breathing and HMV.

  11. Acute respiratory failure and mechanical ventilation in pregnant patient: A narrative review of literature

    PubMed Central

    Bhatia, Pradeep Kumar; Biyani, Ghansham; Mohammed, Sadik; Sethi, Priyanka; Bihani, Pooja

    2016-01-01

    Physiological changes of pregnancy imposes higher risk of acute respiratory failure (ARF) with even a slight insult and remains an important cause of maternal and fetal morbidity and mortality. Although pregnant women have different respiratory physiology and different causes of ARF, guidelines specific to ventilatory settings, goals of oxygenation and weaning process could not be framed due to lack of large-scale randomized controlled trials. During the 2009 H1N1 pandemic, pregnant women had higher morbidity and mortality compared to nonpregnant women. During this period, alternative strategies of ventilation such as high-frequency oscillatory ventilation, inhalational of nitric oxide, prone positioning, and extra corporeal membrane oxygenation were increasingly used as a desperate measure to rescue pregnant patients with severe hypoxemia who were not improving with conventional mechanical ventilation. This article highlights the causes of ARF and recent advances in invasive, noninvasive and alternative strategies of ventilation used during pregnancy. PMID:28096571

  12. Evaluation of self-perception of mechanical ventilation knowledge among Brazilian final-year medical students, residents and emergency physicians

    PubMed Central

    Tallo, Fernando Sabia; de Campos Vieira Abib, Simone; de Andrade Negri, Alexandre Jorgi; Filho, Paulo Cesar; Lopes, Renato Delascio; Lopes, Antônio Carlos

    2017-01-01

    OBJECTIVE: To present self-assessments of knowledge about mechanical ventilation made by final-year medical students, residents, and physicians taking qualifying courses at the Brazilian Society of Internal Medicine who work in urgent and emergency settings. METHODS: A 34-item questionnaire comprising different areas of knowledge and training in mechanical ventilation was given to 806 medical students, residents, and participants in qualifying courses at 11 medical schools in Brazil. The questionnaire’s self-assessment items for knowledge were transformed into scores. RESULTS: The average score among all participants was 21% (0-100%). Of the total, 85% respondents felt they did not receive sufficient information about mechanical ventilation during medical training. Additionally, 77% of the group reported that they would not know when to start noninvasive ventilation in a patient, and 81%, 81%, and 89% would not know how to start volume control, pressure control and pressure support ventilation modes, respectively. Furthermore, 86.4% and 94% of the participants believed they would not identify the basic principles of mechanical ventilation in patients with obstructive pulmonary disease and acute respiratory distress syndrome, respectively, and would feel insecure beginning ventilation. Finally, 77% said they would fear for the safety of a patient requiring invasive mechanical ventilation under their care. CONCLUSION: Self-assessment of knowledge and self-perception of safety for managing mechanical ventilation were deficient among residents, students and emergency physicians from a sample in Brazil. PMID:28273238

  13. Mechanical ventilation in patients subjected to extracorporeal membrane oxygenation (ECMO).

    PubMed

    López Sanchez, M

    2017-02-08

    Mechanical ventilation (MV) is a crucial element in the management of acute respiratory distress syndrome (ARDS), because there is high level evidence that a low tidal volume of 6ml/kg (protective ventilation) improves survival. In these patients with refractory respiratory insufficiency, venovenous extracorporeal membrane oxygenation (ECMO) can be used. This salvage technique improves oxygenation, promotes CO2 clearance, and facilitates protective and ultraprotective MV, potentially minimizing ventilation-induced lung injury. Although numerous trials have investigated different ventilation strategies in patients with ARDS, consensus is lacking on the optimal MV settings during venovenous ECMO. Although the concept of "lung rest" was introduced years ago, there are no evidence-based guidelines on its use in application to MV in patients supported by ECMO. How MV in ECMO patients can promote lung recovery and weaning from ventilation is not clear. The purpose of this review is to describe the ventilation strategies used during venovenous ECMO in clinical practice.

  14. Ammonia emissions from two mechanically ventilated UK livestock buildings

    NASA Astrophysics Data System (ADS)

    Demmers, T. G. M.; Burgess, L. R.; Short, J. L.; Phillips, V. R.; Clark, J. A.; Wathes, C. M.

    Ammonia emission rates from livestock buildings are required to construct an accurate emission inventory for the UK. Ventilation and ammonia emission rates from a fattening pig unit and a broiler house, both mechanically ventilated, were estimated using fan wheel anemometers and thermal converters with a chemiluminescence NO x-analyser to measure the ventilation rate and the ammonia concentration, respectively. The estimated ammonia emission factors were 46.9 and 16.6 kg lu -1 a -1 for the fattening pig unit and the broiler house, respectively. Both emission factors were within the range reported in the literature. A tracer gas (CO) method, based on a constant tracer release rate, was validated for measuring ventilation rates from naturally ventilated livestock buildings. Air inlets and outlets were identified using the air temperature or tracer concentration in the opening. Tracer concentration was found to be a more suitable criterion than temperature. In both houses, a significant correlation between the estimated ventilation rate using the tracer method and the measured ventilation rate using fan wheel anemometers was found. The ventilation rate was underestimated by 12 and 6% for the piggery and broiler house, respectively. The instantaneous ammonia emission derived from the tracer gas method was lower than the ammonia emission derived from the fan wheel anemometer method by 14 and 16% for the piggery and broiler house, respectively. The ventilation and ammonia emission estimates using the tracer method were within acceptable range from the ventilation and emission rates measured using measuring fans, but because of its accuracy and simplicity the fan wheel anemometer method is preferred for long-term measurements of ventilation rate in mechanically ventilated buildings.

  15. Amyotrophic Lateral Sclerosis Patients' Perspectives on Use of Mechanical Ventilation.

    ERIC Educational Resources Information Center

    Young, Jenny M.; And Others

    1994-01-01

    Interviewed 13 amyotrophic lateral sclerosis patients. All believed that they alone should make decision regarding use of mechanical ventilation. Factors they considered important were quality of life, severity of disability, availability of ventilation by means of nasal mask, possible admission to long-term care facility, ability to discontinue…

  16. A Porcine Model for Initial Surge Mechanical Ventilator Assessment and Evaluation of Two Limited Function Ventilators

    PubMed Central

    Dickson, Robert P; Hotchkin, David L; Lamm, Wayne JE; Hinkson, Carl; Pierson, David J; Glenny, Robb W; Rubinson, Lewis

    2013-01-01

    Objective To adapt an animal model of acute lung injury for use as a standard protocol for a screening, initial evaluation of limited function, or “surge,” ventilators for use in mass casualty scenarios. Design Prospective, experimental animal study. Setting University research laboratory. Subjects 12 adult pigs. Interventions 12 spontaneously breathing pigs (6 in each group) were subjected to acute lung injury/acute respiratory distress syndrome (ALI/ARDS) via pulmonary artery infusion of oleic acid. Following development of respiratory failure, animals were mechanically ventilated with a limited function ventilator (Simplified Automatic Ventilator [SAVe] I or II; Automedx) for one hour or until the ventilator could not support the animal. The limited function ventilator was then exchanged for a full function ventilator (Servo 900C; Siemens). Measurements and Main Results Reliable and reproducible levels of ALI/ARDS were induced. The SAVe I was unable to adequately oxygenate 5 animals, with PaO2 (52.0 ± 11.1 torr) compared to the Servo (106.0 ± 25.6 torr; p=0.002). The SAVe II was able to oxygenate and ventilate all 6 animals for one hour with no difference in PaO2 (141.8 ± 169.3 torr) compared to the Servo (158.3 ± 167.7 torr). Conclusions We describe a novel in vivo model of ALI/ARDS that can be used to initially screen limited function ventilators considered for mass respiratory failure stockpiles, and is intended to be combined with additional studies to defintively assess appropriateness for mass respiratory failure. Specifically, during this study we demonstrate that the SAVe I ventilator is unable to provide sufficient gas exchange, while the SAVe II, with several more functions, was able to support the same level of hypoxemic respiratory failure secondary to ALI/ARDS for one hour. PMID:21187747

  17. Variability in Mechanical Ventilation: What's All the Noise About?

    PubMed

    Naik, Bhiken I; Lynch, Carl; Durbin, Charles G

    2015-08-01

    Controlled mechanical ventilation is characterized by a fixed breathing frequency and tidal volume. Physiological and mathematical models have demonstrated the beneficial effects of varying tidal volume and/or inspiratory pressure during positive-pressure ventilation. The addition of noise (random changes) to a monotonous nonlinear biological system, such as the lung, induces stochastic resonance that contributes to the recruitment of collapsed alveoli and atelectatic lung segments. In this article, we review the mechanism of physiological pulmonary variability, the principles of noise and stochastic resonance, and the emerging understanding that there are beneficial effects of variability during mechanical ventilation.

  18. [Weaning from prolonged mechanical ventilation at 72 hours of spontaneous breathing].

    PubMed

    Villalba, Darío; Plotnikow, Gustavo; Feld, Viviana; Rivero Vairo, Noelia; Scapellato, José; Díaz Nielsen, Ernesto

    2015-01-01

    The aim of this study was to describe the population admitted to a weaning center (WC) to receive invasive mechanical ventilation (MV), analyze their evolution and identify weaning failure predictors. The medical records of 763 patients admitted to the respiratory care service in the period between May 2005 and January 2012 were reviewed; 372 were selected among 415 tracheotomized and mechanically ventilated. Different variables were analyzed as weaning failure predictors. The mean age of patients admitted was 69 years (SD 14.7), 57% were men. The median length of hospitalization in ICU was 33 days (IQR 26-46). Admission to ICU was due to medical causes in 86% of cases. During hospitalization in WC 186 (50%) patients achieved the successful weaning at a median of 13 days (interquartile range-IQR 5-38). A predictor of weaning failure was age. When we studied the subpopulation with partial disconnection of mechanical ventilation, we found a history of COPD and ageas predictors. Although 25% of the patients died, or required referral to a center of major complexity before 2 weeks of hospitalization, more than half of the patients were able to be removed permanently from the invasive mechanical ventilation (MV), this could support the care of chronic critical patients in MV and rehabilitation centers in Argentina because patients in these centers have a chance of weaning from MV, despite the high chances of developing complications.

  19. Sedation in mechanically ventilated patients—time to stay awake?

    PubMed Central

    Moreira, Fabio Tanzillo

    2016-01-01

    On June, 2016, Klompas and colleagues published an article in the Chest entitled “Associations between different sedatives and ventilator-associated events, length of stay, and mortality in patients who were mechanically ventilated”, which investigated the effects of different sedatives on ventilator-associated events (VAEs), length of stay, and mortality in patients who were mechanically ventilated. This study used data of over 9,603 patients in order to investigate patients over the age of 18 who underwent mechanical ventilation for more than 3 days over a 7-year period in a large academic medical center. The investigators found that propofol and dexmedetomidine were associated with less time to extubation compared with benzodiazepines, but dexmedetomidine was also associated with less time to extubation vs. propofol. This study raises important questions about the sedation of critically ill patients. PMID:27826584

  20. Numerical investigation of pulmonary drug delivery under mechanical ventilation conditions

    NASA Astrophysics Data System (ADS)

    Banerjee, Arindam; van Rhein, Timothy

    2012-11-01

    The effects of mechanical ventilation waveform on fluid flow and particle deposition were studied in a computer model of the human airways. The frequency with which aerosolized drugs are delivered to mechanically ventilated patients demonstrates the importance of understanding the effects of ventilation parameters. This study focuses specifically on the effects of mechanical ventilation waveforms using a computer model of the airways of patient undergoing mechanical ventilation treatment from the endotracheal tube to generation G7. Waveforms were modeled as those commonly used by commercial mechanical ventilators. Turbulence was modeled with LES. User defined particle force models were used to model the drag force with the Cunningham correction factor, the Saffman lift force, and Brownian motion force. The endotracheal tube (ETT) was found to be an important geometric feature, causing a fluid jet towards the right main bronchus, increased turbulence, and a recirculation zone in the right main bronchus. In addition to the enhanced deposition seen at the carinas of the airway bifurcations, enhanced deposition was also seen in the right main bronchus due to impaction and turbulent dispersion resulting from the fluid structures created by the ETT. Authors acknowledge financial support through University of Missouri Research Board Award.

  1. Fatal brain gas embolism during non-invasive positive pressure ventilation

    PubMed Central

    Rivara, Claire B; Chevrolet, Jean-Claude; Gasche, Yvan; Charbonney, Emmanuel

    2008-01-01

    Gas embolism is a dreaded complication following invasive medical procedures, traumatic lung injury and decompression accidents. We report a case of fatal gas embolism following the use of non-invasive ventilation (NIV) with bilevel positive airway pressure (BiPAP). The patient initially underwent left bronchial artery embolisation for massive haemoptysis in the context of severe tuberculotic sequels. Under NIV and after heavy coughing he became hemiparetic and his level of consciousness suddenly dropped. Computed tomography of the brain showed multiple air embolism and ischaemic lesions were confirmed by magnetic resonance imaging. Echocardiographic investigations showed no intracardiac defect. Vasculo-pulmonary abnormalities in the context of heavy coughing and non-invasive ventilation may have played a major role in the occurrence of this event. New neurological events in a patient with tuberculotic sequels or any known vascular pulmonary abnormalities and NIV should raise the suspicion of brain gas embolism. PMID:21716825

  2. Leakage estimation using Kalman filtering in noninvasive mechanical ventilation.

    PubMed

    Rodrigues, G G; Freitas, U S; Bounoiare, D; Aguirre, L A; Letellier, C

    2013-05-01

    Noninvasive mechanical ventilation is today often used to assist patient with chronic respiratory failure. One of the main reasons evoked to explain asynchrony events, discomfort, unwillingness to be treated, etc., is the occurrence of nonintentional leaks in the ventilation circuit, which are difficult to account for because they are not measured. This paper describes a solution to the problem of variable leakage estimation based on a Kalman filter driven by airflow and the pressure signals, both of which are available in the ventilation circuit. The filter was validated by showing that based on the attained leakage estimates, practically all the untriggered cycles can be explained.

  3. Non-invasive ventilation in prone position for refractory hypoxemia after bilateral lung transplantation.

    PubMed

    Feltracco, Paolo; Serra, Eugenio; Barbieri, Stefania; Persona, Paolo; Rea, Federico; Loy, Monica; Ori, Carlo

    2009-01-01

    Temporary graft dysfunction with gas exchange abnormalities is a common finding during the postoperative course of a lung transplant and is often determined by the post-reimplantation syndrome. Supportive measures including oxygen by mask, inotropes, diuretics, and pulmonary vasodilators are usually effective in non-severe post-reimplantation syndromes. However, in less-responsive clinical pictures, tracheal intubation with positive pressure ventilation, or non-invasive positive pressure ventilation (NIV), is necessary. We report on the clinical course of two patients suffering from refractory hypoxemia due to post-reimplantation syndrome treated with NIV in the prone and Trendelenburg positions. NIV was well tolerated and led to resolution of atelectactic areas and dishomogeneous lung infiltrates. Repeated turning from supine to prone under non invasive ventilation determined a stable improvement of gas exchange and prevented a more invasive approach. Even though NIV in the prone position has not yet entered into clinical practice, it could be an interesting option to achieve a better match between ventilation and perfusion. This technique, which we successfully applied in lung transplantation, can be easily extended to other lung diseases with non-recruitable dorso-basal areas.

  4. Noninvasive mechanical ventilation in chronic obstructive pulmonary disease and in acute cardiogenic pulmonary edema.

    PubMed

    Rialp Cervera, G; del Castillo Blanco, A; Pérez Aizcorreta, O; Parra Morais, L

    2014-03-01

    Noninvasive ventilation (NIV) with conventional therapy improves the outcome of patients with acute respiratory failure due to hypercapnic decompensation of chronic obstructive pulmonary disease (COPD) or acute cardiogenic pulmonary edema (ACPE). This review summarizes the main effects of NIV in these pathologies. In COPD, NIV improves gas exchange and symptoms, reducing the need for endotracheal intubation, hospital mortality and hospital stay compared with conventional oxygen therapy. NIV may also avoid reintubation and may decrease the length of invasive mechanical ventilation. In ACPE, NIV accelerates the remission of symptoms and the normalization of blood gas parameters, reduces the need for endotracheal intubation, and is associated with a trend towards lesser mortality, without increasing the incidence of myocardial infarction. The ventilation modality used in ACPE does not affect the patient prognosis.

  5. Utility of Transcutaneous Capnography for Optimization of Non-Invasive Ventilation Pressures

    PubMed Central

    Gehrer, Simone; Pandey, Kamlesh V; Vaidya, Preyas J; Leuppi, Joerg D.; Tamm, Michael; Strobel, Werner

    2016-01-01

    Introduction Nocturnal Non-invasive Positive Pressure Ventilation (NPPV) is the treatment of choice in patients with chronic hypercapnic respiratory failure due to hypoventilation. Continuous oxygen saturation measured with a pulse oximeter provides a surrogate measure of arterial oxygen saturation but does not completely reflect ventilation. Currently, Partial Pressure of Arterial (PaCO2) measured by arterial blood analysis is used for estimating the adequacy of ventilatory support and serves as the gold standard Aim To examine the safety, feasibility and utility of cutaneous capnography to re-titrate the non-invasive positive pressure ventilation settings in patients with chronic hypercapnic respiratory failure due to hypoventilation. Materials and Methods Twelve patients with chronic hypercapnic respiratory failure prospectively underwent complete polysomnography and cutaneous capnography measurement on the ear lobe. Non-invasive ventilation pressures were adjusted with the aim of normalizing cutaneous carbon dioxide or at least reducing it by 10 to 15 mmHg. Sensor drift for cutaneous carbon dioxide of 0.7 mmHg per hour was integrated in the analysis. Results Mean baseline cutaneous carbon dioxide was 45.4 ± 6.5 mmHg and drift corrected awake value was 45.1 ± 8.3 mmHg. The correlation of baseline cutaneous carbon dioxide and the corrected awake cutaneous carbon dioxide with arterial blood gas values were 0.91 and 0.85 respectively. Inspiratory positive airway pressures were changed in nine patients (75%) and expiratory positive airway pressures in eight patients (66%). Epworth sleepiness score before and after the study showed no change in five patients, improvement in six patients and deterioration in one patient. Conclusion Cutaneous capnography is feasible and permits the optimization of non-invasive ventilation pressure settings in patients with chronic hypercapnic respiratory failure due to hypoventilation. Continuous cutaneous capnography might serve as

  6. Non-invasive ventilation in the treatment of sleep-related breathing disorders: A review and update.

    PubMed

    Nicolini, A; Banfi, P; Grecchi, B; Lax, A; Walterspacher, S; Barlascini, C; Robert, D

    2014-01-01

    Non-invasive mechanical ventilation (NIV) was originally used in patients with acute respiratory compromises or exacerbations of chronic respiratory diseases as an alternative to intubation. Over the last thirty years NIV has been used during the night in patients with stable chronic lung diseases such as obstructive sleep apnea, the overlap syndrome (COPD and obstructive sleep apnea), neuromuscular disorders, obesity-hypoventilation syndrome and in other conditions such as sleep disorders associated with congestive heart failure. In this review we discuss the different types of NIV, the specific conditions in which they can be used as well as the indications, recommendations, and evidence supporting the efficacy of NIV.

  7. Enteral alimentation and gastrointestinal bleeding in mechanically ventilated patients.

    PubMed

    Pingleton, S K; Hadzima, S K

    1983-01-01

    The incidence of upper gastrointestinal (GI) bleeding in mechanically ventilated ICU patients receiving enteral alimentation was reviewed and compared to bleeding occurring in ventilated patients receiving prophylactic antacids or cimetidine. Of 250 patients admitted to our ICU during a 1-yr time period, 43 ventilated patients were studied. Patients in each group were comparable with respect to age, respiratory diagnosis, number of GI hemorrhage risk factors, and number of ventilator, ICU, and hospital days. Twenty-one patients had evidence of GI bleeding. Fourteen of 20 patients receiving antacids and 7 of 9 patients receiving cimetidine had evidence of GI bleeding. No bleeding occurred in 14 patients receiving enteral alimentation. Complications of enteral alimentation were few and none required discontinuation of enteral alimentation. Our preliminary data suggest the role of enteral alimentation in critically ill patients may include not only protection against malnutrition but also protection against GI bleeding.

  8. Long term non-invasive domiciliary assisted ventilation for respiratory failure following thoracoplasty.

    PubMed Central

    Jackson, M.; Smith, I.; King, M.; Shneerson, J.

    1994-01-01

    BACKGROUND--Ventilatory failure is a well recognised complication of patients who have had a thoracoplasty for tuberculosis, but there are few data regarding the value of long term non-invasive assisted ventilation in this situation. METHODS--Thirty two patients who had had a thoracoplasty 20-46 years previously and who had developed respiratory failure were treated with nocturnal cuirass assisted ventilation or nasal positive pressure ventilation. Their survival and changes in arterial blood gases, nocturnal oximetry, and pulmonary function tests were assessed. RESULTS--The actuarial survival rates at one, three, five, and seven years after starting treatment were 91%, 74%, 64%, and 55%, respectively. Only seven of the 13 deaths were directly attributable to chronic respiratory or cardiac failure. The arterial PO2, PCO2, mean nocturnal oxygen saturation, vital capacity, and maximal inspiratory and expiratory pressures had all improved at the time of the initial post-treatment assessment (mean 12 days after starting treatment), but no subsequent improvements were seen after up to 48 months of follow up. Neither survival nor physiological improvements were correlated with the patients' age, the interval since thoracoplasty, or the pretreatment arterial blood gas tensions or results of pulmonary function tests. CONCLUSIONS--These results show that, even when ventilatory failure has developed, the prognosis with non-invasive assisted ventilation is good and the physiological abnormalities can be partially reversed. Patients who develop respiratory failure after a thoracoplasty should be considered for this type of long term domiciliary treatment. PMID:7940434

  9. Links between the mechanics of ventilation and spine stability.

    PubMed

    Wang, Simon; McGill, Stuart M

    2008-05-01

    Spine stability is ensured through isometric coactivation of the torso muscles; however, these same muscles are used cyclically to assist ventilation. Our objective was to investigate this apparent paradoxical role (isometric contraction for stability or rhythmic contraction for ventilation) of some selected torso muscles that are involved in both ventilation and support of the spine. Eight, asymptomatic, male subjects provided data on low back moments, motion, muscle activation, and hand force. These data were input to an anatomically detailed, biologically driven model from which spine load and a lumbar spine stability index was obtained. Results revealed that subjects entrained their torso stabilization muscles to breathe during demanding ventilation tasks. Increases in lung volume and back extensor muscle activation coincided with increases in spine stability, whereas declines in spine stability were observed during periods of low lung inflation volume and simultaneously low levels of torso muscle activation. As a case study, aberrant ventilation motor patterns (poor muscle entrainment), seen in one subject, compromised spine stability. Those interested in rehabilitation of patients with lung compromise and concomitant back troubles would be assisted with knowledge of the mechanical links between ventilation during tasks that impose spine loading.

  10. Mechanical exsufflation, noninvasive ventilation, and new strategies for pulmonary rehabilitation and sleep disordered breathing.

    PubMed Central

    Bach, J. R.

    1992-01-01

    Manual and mechanical exsufflation are important but underutilized ways to clear airway secretions. These methods are especially useful when used in concert with noninvasive intermittent positive airway pressure ventilatory assistance to facilitate extubation and ventilator weaning. This can be used as much as 24 hours a day as an alternative to tracheostomy ventilation or body ventilator use for patients with paralytic restrictive ventilatory insufficiency. These techniques expedite community management of ventilator assisted individuals by avoiding tracheostomy and need for invasive suctioning and ongoing wound care. For these techniques to be effective and to prevent further suppression of ventilatory drive, supplemental oxygen administration must be avoided unless pO2 is less than 60 mm Hg despite normalization of pCO2. Custom molded interfaces for the delivery of noninvasive intermittent positive airway pressure ventilatory assistance can also be used to facilitate the delivery of variable inspiratory expiratory positive airway pressure for patients with obstructive sleep apnea. Noninvasive intermittent positive airway pressure ventilatory assistance or body ventilator use can rest the respiratory muscles of patients with advanced chronic obstructive pulmonary disease. This and pulmonary rehabilitation programs geared to exercise reconditioning are therapeutic options that significantly improve the quality of life of these patients. For both paralytic restrictive and obstructive pulmonary patients, these techniques decrease cost and frequency of hospitalizations. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:1586868

  11. Weaning from mechanical ventilation in paediatrics. State of the art.

    PubMed

    Valenzuela, Jorge; Araneda, Patricio; Cruces, Pablo

    2014-03-01

    Weaning from mechanical ventilation is one of the greatest volume and strength issues in evidence-based medicine in critically ill adults. In these patients, weaning protocols and daily interruption of sedation have been implemented, reducing the duration of mechanical ventilation and associated morbidity. In paediatrics, the information reported is less consistent, so that as yet there are no reliable criteria for weaning and extubation in this patient group. Several indices have been developed to predict the outcome of weaning. However, these have failed to replace clinical judgement, although some additional measurements could facilitate this decision.

  12. Lung mechanics in the TIMP3 null mouse and its response to mechanical ventilation.

    PubMed

    Martin, Erica L; Truscott, Emily A; Bailey, Timothy C; Leco, Kevin J; McCaig, Lynda A; Lewis, James F; Veldhuizen, Ruud A W

    2007-03-01

    Tissue inhibitor of metalloproteinase-3 (TIMP3) null mice develop emphysema-like airspace enlargement due to an enzymatic imbalance. This study investigates how these abnormalities alter lung mechanics and the response to 2 different mechanical ventilation strategies. Phenotypically, TIMP3 null mice had increased compliance, and decreased resistance, tissue damping, and tissue elastance over wild-type controls. Decreased compliance and increased resistance were observed following the injurious ventilation strategy; however, the TIMP3 null response to both ventilation strategies was similar to wild-type mice. In conclusion, TIMP3 null mice have significant alterations in lung mechanics; however, this does not affect their response to ventilation.

  13. From mechanical ventilation to intensive care medicine: a challenge for Bosnia and Herzegovina.

    PubMed

    Thiéry, Guillaume; Kovacević, Pedja; Straus, Slavenka; Vidovic, Jadranka; Iglica, Amer; Festic, Emir; Gajic, Ognjen

    2009-10-01

    Intensive care medicine is a relatively new specialty, which was created in the 1950's, after invent of mechanical ventilation, which allowed caring for critically ill patients who otherwise would have died. First created for treating mechanically ventilated patients, ICUs extended their scope and care to all patients with life threatening conditions. Over the years, intensive care medicine developed further and became a truly multidisciplinary speciality, encompassing patients from various fields of medicine and involving specialists from a range of base specialties, with additional (subspecialty) training in intensive care medicine. In Bosnia and Herzegovina, the founding of the society of intensive care medicine in 2006, the introduction of non invasive ventilation in 2007, and opening of a multidisciplinary ICUs in Banja Luka and Sarajevo heralded a new age of intensive care medicine. The number of admissions, high severity scores and needs for mechanical ventilation during the first several months in the medical ICU in Banja Luka confirmed the need of these kinds of units in the country. In spite of still suboptimal personnel training, creation of ICUs in Bosnia and Herzegovina may serve as example for other developing countries in the region. However, in order to achieve modern ICU standards and follow European trends toward harmonisation of medicine, Bosnia and Herzegovina needs to take up this challenge by recognizing intensive care medicine as a distinctive specialty, by implementing a specific training program and by setting up multidisciplinary ICUs in acute care hospitals.

  14. Lung hyperinflation by mechanical ventilation versus isolated tracheal aspiration in the bronchial hygiene of patients undergoing mechanical ventilation

    PubMed Central

    Assmann, Crisiela Brum; Vieira, Paulo José Cardoso; Kutchak, Fernanda; Rieder, Marcelo de Mello; Forgiarini, Soraia Genebra Ibrahim; Forgiarini Junior, Luiz Alberto

    2016-01-01

    Objective To determine the efficacy of lung hyperinflation maneuvers via a mechanical ventilator compared to isolated tracheal aspiration for removing secretions, normalizing hemodynamics and improving lung mechanics in patients on mechanical ventilation. Methods This was a randomized crossover clinical trial including patients admitted to the intensive care unit and on mechanical ventilation for more than 48 hours. Patients were randomized to receive either isolated tracheal aspiration (Control Group) or lung hyperinflation by mechanical ventilator (MVH Group). Hemodynamic and mechanical respiratory parameters were measured along with the amount of aspirated secretions. Results A total of 50 patients were included. The mean age of the patients was 44.7 ± 21.6 years, and 31 were male. Compared to the Control Group, the MVH Group showed greater aspirated secretion amount (3.9g versus 6.4g, p = 0.0001), variation in mean dynamic compliance (-1.3 ± 2.3 versus -2.9 ± 2.3; p = 0.008), and expired tidal volume (-0.7 ± 0.0 versus -54.1 ± 38.8, p = 0.0001) as well as a significant decrease in peak inspiratory pressure (0.2 ± 0.1 versus 2.5 ± 0.1; p = 0.001). Conclusion In the studied sample, the MVH technique led to a greater amount of aspirated secretions, significant increases in dynamic compliance and expired tidal volume and a significant reduction in peak inspiratory pressure. PMID:27096673

  15. Improved survival with an ambulatory model of non-invasive ventilation implementation in motor neuron disease.

    PubMed

    Sheers, Nicole; Berlowitz, David J; Rautela, Linda; Batchelder, Ian; Hopkinson, Kim; Howard, Mark E

    2014-06-01

    Non-invasive ventilation (NIV) increases survival and quality of life in motor neuron disease (MND). NIV implementation historically occurred during a multi-day inpatient admission at this institution; however, increased demand led to prolonged waiting times. The aim of this study was to evaluate the introduction of an ambulatory model of NIV implementation. A prospective cohort study was performed. Inclusion criteria were referral for NIV implementation six months pre- or post-commencement of the Day Admission model. This model involved a 4-h stay to commence ventilation with follow-up in-laboratory polysomnography titration and outpatient attendance. Outcome measures included waiting time, hospital length of stay, adverse events and polysomnography data. Results indicated that after changing to the Day Admission model the median waiting time fell from 30 to 13.5 days (p < 0.04) and adverse events declined (4/17 pre- (three deaths, one acute admission) vs. 0/12 post-). Survival was also prolonged (median (IQR) 278 (51-512) days pre- vs 580 (306-1355) days post-introduction of the Day Admission model; hazard ratio 0.41, p = 0.04). Daytime PaCO2 was no different. In conclusion, reduced waiting time to commence ventilation and improved survival were observed following introduction of an ambulatory model of NIV implementation in people with MND, with no change in the effectiveness of ventilation.

  16. Non-invasive ventilation in chronic obstructive pulmonary disease: management of acute type 2 respiratory failure.

    PubMed

    Roberts, C M; Brown, J L; Reinhardt, A K; Kaul, S; Scales, K; Mikelsons, C; Reid, K; Winter, R; Young, K; Restrick, L; Plant, P K

    2008-10-01

    Non-invasive ventilation (NIV) in the management of acute type 2 respiratory failure in patients with chronic obstructive pulmonary disease (COPD) represents one of the major technical advances in respiratory care over the last decade. This document updates the 2002 British Thoracic Society guidance and provides a specific focus on the use of NIV in COPD patients with acute type 2 respiratory failure. While there are a variety of ventilator units available most centres now use bi-level positive airways pressure units and this guideline refers specifically to this form of ventilatory support although many of the principles encompassed are applicable to other forms of NIV. The guideline has been produced for the clinician caring for COPD patients in the emergency and ward areas of acute hospitals.

  17. Mechanical ventilation in mass casualty scenarios. Augmenting staff: project XTREME.

    PubMed

    Hanley, Michael E; Bogdan, Gregory M

    2008-02-01

    Disaster preparedness typically includes plans that address the need for surge capacity to manage mass-casualty events. A major concern of disaster preparedness in respiratory therapy focuses on responding to a sudden increase in the volume of patients who require mechanical ventilation. Plans for such disasters must include contingencies to address surge capacity in ventilator inventories and the respiratory therapy staff who will manage the ventilators. Tactics to address these situations include efforts to lower demand by transferring patients to other institutions as well as efforts to augment staffing levels. Staff can be augmented by mobilization of deployable teams of volunteers from outside the region and through exploitation of local resources. The latter includes strategies to recruit local respiratory therapists who are currently in either non-clinical or non-hospital-based positions and policies that optimize existing respiratory therapy resources within an institution by canceling elective surgeries, altering shift structure, and postponing vacations. An alternative approach would employ non-respiratory-therapy staff to assist in the management of patients with respiratory failure. Project XTREME (Cross-Training Respiratory Extenders for Medical Emergencies) is a cross-training program developed to facilitate training of non-respiratory-therapy health professionals to assist in the management of patients who require mechanical ventilation. It includes an interactive digital video disc as well as a competency validation laboratory and is designed to be performed at the time of an emergency. Pilot testing of the program suggests it is effective.

  18. Automated mechanical ventilation: adapting decision making to different disease states.

    PubMed

    Lozano-Zahonero, S; Gottlieb, D; Haberthür, C; Guttmann, J; Möller, K

    2011-03-01

    The purpose of the present study is to introduce a novel methodology for adapting and upgrading decision-making strategies concerning mechanical ventilation with respect to different disease states into our fuzzy-based expert system, AUTOPILOT-BT. The special features are: (1) Extraction of clinical knowledge in analogy to the daily routine. (2) An automated process to obtain the required information and to create fuzzy sets. (3) The controller employs the derived fuzzy rules to achieve the desired ventilation status. For demonstration this study focuses exclusively on the control of arterial CO(2) partial pressure (p(a)CO(2)). Clinical knowledge from 61 anesthesiologists was acquired using a questionnaire from which different disease-specific fuzzy sets were generated to control p(a)CO(2). For both, patients with healthy lung and with acute respiratory distress syndrome (ARDS) the fuzzy sets show different shapes. The fuzzy set "normal", i.e., "target p(a)CO(2) area", ranges from 35 to 39 mmHg for healthy lungs and from 39 to 43 mmHg for ARDS lungs. With the new fuzzy sets our AUTOPILOT-BT reaches the target p(a)CO(2) within maximal three consecutive changes of ventilator settings. Thus, clinical knowledge can be extended, updated, and the resulting mechanical ventilation therapies can be individually adapted, analyzed, and evaluated.

  19. Microbial profiling of dental plaque from mechanically ventilated patients.

    PubMed

    Sands, Kirsty M; Twigg, Joshua A; Lewis, Michael A O; Wise, Matt P; Marchesi, Julian R; Smith, Ann; Wilson, Melanie J; Williams, David W

    2016-02-01

    Micro-organisms isolated from the oral cavity may translocate to the lower airways during mechanical ventilation (MV) leading to ventilator-associated pneumonia (VAP). Changes within the dental plaque microbiome during MV have been documented previously, primarily using culture-based techniques. The aim of this study was to use community profiling by high throughput sequencing to comprehensively analyse suggested microbial changes within dental plaque during MV. Bacterial 16S rDNA gene sequences were obtained from 38 samples of dental plaque sampled from 13 mechanically ventilated patients and sequenced using the Illumina platform. Sequences were processed using Mothur, applying a 97% gene similarity cut-off for bacterial species level identifications. A significant 'microbial shift' occurred in the microbial community of dental plaque during MV for nine out of 13 patients. Following extubation, or removal of the endotracheal tube that facilitates ventilation, sampling revealed a decrease in the relative abundance of potential respiratory pathogens and a compositional change towards a more predominantly (in terms of abundance) oral microbiota including Prevotella spp., and streptococci. The results highlight the need to better understand microbial shifts in the oral microbiome in the development of strategies to reduce VAP, and may have implications for the development of other forms of pneumonia such as community-acquired infection.

  20. Mechanical Ventilation Boot Camp: A Simulation-Based Pilot Study

    PubMed Central

    Yee, Jennifer; Fuenning, Charles; George, Richard; Hejal, Rana; Haines, Nhi; Dunn, Diane; Gothard, M. David; Ahmed, Rami A.

    2016-01-01

    Objectives. Management of mechanically ventilated patients may pose a challenge to novice residents, many of which may not have received formal dedicated critical care instruction prior to starting their residency training. There is a paucity of data regarding simulation and mechanical ventilation training in the medical education literature. The purpose of this study was to develop a curriculum to educate first-year residents on addressing and troubleshooting ventilator alarms. Methods. Prospective evaluation was conducted of seventeen residents undergoing a twelve-hour three-day curriculum. Residents were assessed using a predetermined critical action checklist for each case, as well as pre- and postcurriculum multiple-choice cognitive knowledge questionnaires and confidence surveys. Results. Significant improvements in cognitive knowledge, critical actions, and self-reported confidence were demonstrated. The mean change in test score from before to after intervention was +26.8%, and a median score increase of 25% was noted. The ARDS and the mucus plugging cases had statistically significant improvements in critical actions, p < 0.001. A mean increase in self-reported confidence was realized (1.55 to 3.64), p = 0.049. Conclusions. A three-day simulation curriculum for residents was effective in increasing competency, knowledge, and confidence with ventilator management. PMID:26949545

  1. Ventilation.

    PubMed

    Turner, W A; Bearg, D W; Brennan, T

    1995-01-01

    This chapter begins with an overview of the history of ventilation guidelines, which has led to the guidelines that are in effect today. Of particular interest is the most recent return in the past 5 years to ventilation rates that more closely reflect a mean or average of the range of guidelines that have existed over the past century. OSHA's and the EPA's recognition of the need to operate ventilation systems in buildings in an accountable manner is also of note. Of even more interest is the resurgence of the concept of minimum mixing and once-through ventilation air that has been pursued in parts of Northern Europe for the past 10 years, and in a school that is being designed with this concept in New Hampshire. In addition, the design concept of equipping office buildings with low pressure drop high efficiency particle filtration to remove fine particles from all of the air that is supplied to the occupants is being used increasingly in the U.S. This chapter also presents an overview of the various types of ventilation systems found in homes and commercial office buildings and the common indoor air quality problems that may be associated with them. It also offers an overview of common HVAC evaluation techniques that can be used to determine if a ventilation system is performing in a manner that makes sense for the use of the space and the needs of the occupants. Are the occupants receiving a reasonable supply of outdoor air? Is the air that they receive of reasonable quality? Are obvious pollutants being exhausted? Ventilation systems have become extremely complex and more difficult to run and maintain over the past 40 years. This trend will continue to drive the need for professionally maintained HVAC equipment that is serviced and run by individuals who are accountable for the quality of the air that the system delivers.

  2. Best Practices for Managing Pain, Sedation, and Delirium in the Mechanically Ventilated Patient.

    PubMed

    Garrett, Kitty M

    2016-12-01

    Nursing management of pain, agitation, and delirium in mechanically ventilated patients is a challenge in critical care. Oversedation can lead to delayed extubation, prolonged ventilator days, unnecessary neurologic testing, and complications such as weakness and delirium. Undersedation can lead to self-extubation, invasive line removal, unnecessary patient distress, and injury to self or others. Acquiring an optimal level of sedation requires the bedside nurse to be more vigilant than ever with patient assessment and medication titration. This article provides a historical perspective of the management of pain, agitation, and delirium, and disseminates information contained in revised Society for Critical Care Medicine Clinical Practice Guidelines (January 2013) to promote their implementation in day-to-day nursing care.

  3. Ventilation distribution and chest wall mechanics in microgravity

    NASA Technical Reports Server (NTRS)

    Paiva, M.; Wantier, M.; Verbanck, S.; Engel, L. A.; Prisk, G. K.; Guy, H. J. B.; West, J. B.

    1997-01-01

    The effect of gravity on lung ventilation distribution and the mechanisms of the chest wall were investigated. The following tests were performed with the respiratory monitoring system of the Anthorack, flown onboard Spacelab D2 mission: single breath washout (SBW), multiple breath washout (MBW) and argon rebreathing (ARB). In order to study chest wall mechanisms in microgravity, a respiratory inductive plethysmograph was used. The SBW tests did not reach statistical significance, while the ARB tests showed that gravity independent inhomogeneity of specific ventilation is larger than gravity dependent inhomogeneity. In which concerns the chest wall mechanisms, the analysis on the four astronauts during the normal respirations of the relaxation maneuver showed a 40 percent increase on the abdominal contribution to respiration.

  4. [Lung-brain interaction in the mechanically ventilated patient].

    PubMed

    López-Aguilar, J; Fernández-Gonzalo, M S; Turon, M; Quílez, M E; Gómez-Simón, V; Jódar, M M; Blanch, L

    2013-10-01

    Patients with acute lung injury or acute respiratory distress syndrome (ARDS) admitted to the ICU present neuropsychological alterations, which in most cases extend beyond the acute phase and have an important adverse effect upon quality of life. The aim of this review is to deepen in the analysis of the complex interaction between lung and brain in critically ill patients subjected to mechanical ventilation. This update first describes the neuropsychological alterations occurring both during the acute phase of ICU stay and at discharge, followed by an analysis of lung-brain interactions during mechanical ventilation, and finally explores the etiology and mechanisms leading to the neurological disorders observed in these patients. The management of critical patients requires an integral approach focused on minimizing the deleterious effects over the short, middle or long term.

  5. Depressive Disorders during Weaning from Prolonged Mechanical Ventilation

    PubMed Central

    Jubran, Amal; Lawm, Gerald; Kelly, Joanne; Duffner, Lisa A.; Gungor, Gokay; Collins, Eileen G.; Lanuza, Dorothy M.; Hoffman, Leslie A.; Tobin, Martin J.

    2010-01-01

    Purpose Patients who require mechanical ventilation are at risk of emotional stress because of total dependence on a machine for breathing. The stress may negatively impact ventilator weaning and survival. The purpose of this study was to determine whether depressive disorders in patients being weaned from prolonged mechanical ventilation are linked to weaning failure and decreased survival. Methods A prospective study of 478 consecutive patients transferred to a long-term acute care hospital for weaning from prolonged ventilation was undertaken. A clinical psychologist conducted a psychiatric interview to assess for the presence of depressive disorders. Results Of the 478 patients, 142 had persistent coma or delirium and were unable to be evaluated for depressive disorders. Of the remaining 336 patients, 142 (42%) were diagnosed with depressive disorders. In multivariate analysis, co-morbidity score (odds ratio [OR], 1.23, p=0.007), functional dependence before the acute illness (OR, 1.70, p=0.03), and history of psychiatric disorders (OR, 3.04, p=0.0001) were independent predictors of depressive disorders. The rate of weaning failure was higher in patients with depressive disorders than in those without such disorders (61% versus 33%, p=0.0001), as was mortality (24% versus 10%, p=0.0008). The presence of depressive disorders was independently associated with mortality (OR, 4.3; p=0.0002); age (OR, 1.06; p=0.001) and co-morbidity score (OR, 1.24; p=0.02) also predicted mortality. Conclusion Depressive disorders were diagnosed in 42% of patients who are being weaned from prolonged ventilation. Patients with depressive disorders were more likely to experience weaning failure and death. PMID:20232042

  6. Convexity, Jensen's inequality and benefits of noisy mechanical ventilation.

    PubMed

    Brewster, John F; Graham, M Ruth; Mutch, W Alan C

    2005-09-22

    Mechanical ventilators breathe for you when you cannot or when your lungs are too sick to do their job. Most ventilators monotonously deliver the same-sized breaths, like clockwork; however, healthy people do not breathe this way. This has led to the development of a biologically variable ventilator--one that incorporates noise. There are indications that such a noisy ventilator may be beneficial for patients with very sick lungs. In this paper we use a probabilistic argument, based on Jensen's inequality, to identify the circumstances in which the addition of noise may be beneficial and, equally important, the circumstances in which it may not be beneficial. Using the local convexity of the relationship between airway pressure and tidal volume in the lung, we show that the addition of noise at low volume or low pressure results in higher mean volume (at the same mean pressure) or lower mean pressure (at the same mean volume). The consequence is enhanced gas exchange or less stress on the lungs, both clinically desirable. The argument has implications for other life support devices, such as cardiopulmonary bypass pumps. This paper illustrates the benefits of research that takes place at the interface between mathematics and medicine.

  7. NanoClusters Enhance Drug Delivery in Mechanical Ventilation

    NASA Astrophysics Data System (ADS)

    Pornputtapitak, Warangkana

    The overall goal of this thesis was to develop a dry powder delivery system for patients on mechanical ventilation. The studies were divided into two parts: the formulation development and the device design. The pulmonary system is an attractive route for drug delivery since the lungs have a large accessible surface area for treatment or drug absorption. For ventilated patients, inhaled drugs have to successfully navigate ventilator tubing and an endotracheal tube. Agglomerates of drug nanoparticles (also known as 'NanoClusters') are fine dry powder aerosols that were hypothesized to enable drug delivery through ventilator circuits. This Thesis systematically investigated formulations of NanoClusters and their aerosol performance in a conventional inhaler and a device designed for use during mechanical ventilation. These engineered powders of budesonide (NC-Bud) were delivered via a MonodoseRTM inhaler or a novel device through commercial endotracheal tubes, and analyzed by cascade impaction. NC-Bud had a higher efficiency of aerosol delivery compared to micronized stock budesonide. The delivery efficiency was independent of ventilator parameters such as inspiration patterns, inspiration volumes, and inspiration flow rates. A novel device designed to fit directly to the ventilator and endotracheal tubing connections and the MonodoseRTM inhaler showed the same efficiency of drug delivery. The new device combined with NanoCluster formulation technology, therefore, allowed convenient and efficient drug delivery through endotracheal tubes. Furthermore, itraconazole (ITZ), a triazole antifungal agent, was formulated as a NanoCluster powder via milling (top-down process) or precipitation (bottom-up process) without using any excipients. ITZ NanoClusters prepared by wet milling showed better aerosol performance compared to micronized stock ITZ and ITZ NanoClusters prepared by precipitation. ITZ NanoClusters prepared by precipitation methods also showed an amorphous state

  8. [Central alveolar hypoventilation with cor pulmonale: successful treatment by non-invasive intermittent positive pressure ventilation].

    PubMed

    Montiel, G C; Roncoroni, A J; Quadrelli, S A; De Vito, E L

    1994-01-01

    A 62 year-old woman with a bilateral carotid body paraganglioma presented, 2 years after the removal of the right one, with signs of right-heart failure. Hypoxemia, hypercapnia, polycythemia and pulmonary hypertension with normal ventilatory capacity were found. Central alveolar hypoventilation was diagnosed on the basis of absence of ventilatory response and sensation of provoked hypercapnia, prolonged breath-holding time and correction of hypercapnia by voluntary ventilation. Progesterone (200 mg/d during 3 weeks) or naloxone did not improve either arterial blood gases (ABG) or the P 0.1/PCO2 curve. Hypoxemia and hypercapnia were not corrected during metabolic acidosis provoked by acetazolamide (250 mg/d). Nasal CPAP did not control hypoventilation periods. Mechanical ventilation was initiated with negative pressure (NPV) through a poncho. The patient presented severe discomfort with NPV and obstructive apneas were verified during it. She refused to continue NPV. Mechanical ventilation was initiated with positive intermittent pressure (IPPV) through a nasal mask. The patient had excellent tolerance to the procedure. SpO2 during IPPV was always higher than 95%. During sleep induction (under IPPV), respiration in phase with the ventilator 1: 1 was observed; instead, during consolidated sleep there was a complete dependence of the ventilator with apnea for over 2 min when IPPV was interrupted (Fig. 1). After 2 months of treatment, a relief of right ventricular failure occurred and hematocrit fell to 39%. There was an improvement of day-time ABG (Table I). The P. 0.1/PaCO2 curve 3 months after IPPV was the same as the previous one (Fig. 2). The patient has been for 18 months on home ventilation.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Expiratory flow limitation in morbidly obese postoperative mechanically ventilated patients.

    PubMed

    Koutsoukou, A; Koulouris, N; Bekos, B; Sotiropoulou, C; Kosmas, E; Papadima, K; Roussos, C

    2004-10-01

    Although obesity promotes tidal expiratory flow limitation (EFL), with concurrent dynamic hyperinflation (DH), intrinsic PEEP (PEEPi) and risk of low lung volume injury, the prevalence and magnitude of EFL, DH and PEEPi have not yet been studied in mechanically ventilated morbidly obese subjects. In 15 postoperative mechanically ventilated morbidly obese subjects, we assessed the prevalence of EFL [using the negative expiratory pressure (NEP) technique], PEEPi, DH, respiratory mechanics, arterial oxygenation and PEEPi inequality index as well as the levels of PEEP required to abolish EFL. In supine position at zero PEEP, 10 patients exhibited EFL with a significantly higher PEEPi and DH and a significantly lower PEEPi inequality index than found in the five non-EFL (NEFL) subjects. Impaired gas exchange was found in all cases without significant differences between the EFL and NEFL subjects. Application of 7.5 +/- 2.5 cm H2O of PEEP (range: 4-16) abolished EFL with a reduction of PEEPi and DH and an increase in FRC and the PEEPi inequality index but no significant effect on gas exchange. The present study indicates that: (a) on zero PEEP, EFL is present in most postoperative mechanically ventilated morbidly obese subjects; (b) EFL (and concurrent risk of low lung volume injury) is abolished with appropriate levels of PEEP; and (c) impaired gas exchange is common in these patients, probably mainly due to atelectasis.

  10. Use of volume-targeted non-invasive bilevel positive airway pressure ventilation in a patient with amyotrophic lateral sclerosis*,**

    PubMed Central

    Diaz-Abad, Montserrat; Brown, John Edward

    2014-01-01

    Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease in which most patients die of respiratory failure. Although volume-targeted non-invasive bilevel positive airway pressure (BPAP) ventilation has been studied in patients with chronic respiratory failure of various etiologies, its use in ALS has not been reported. We present the case of a 66-year-old woman with ALS and respiratory failure treated with volume-targeted BPAP ventilation for 15 weeks. Weekly data downloads showed that disease progression was associated with increased respiratory muscle weakness, decreased spontaneous breathing, and increased use of non-invasive positive pressure ventilation, whereas tidal volume and minute ventilation remained relatively constant. PMID:25210968

  11. Pneumothorax, Pneumomediastinum, Pneumoperitoneum and Surgical Emphysema in Mechanically Ventilated Patients

    PubMed Central

    Kamha, A; Alzeer, H; Elithy, M

    2008-01-01

    A 29 year old male patient of Indian ancestry was admitted to an outside hospital with rapid deterioration of his level of consciousness. The patient required mechanical ventilation and transfer to MICU at Hamad Medical Corporation. The patient remained hypoxic. Chest X-ray, CT of chest, abdomen, pelvis and proximal areas of both lower limbs were performed. Pneumomediastinum, pneumoperitoneum, and extensive surgical emphysema were the diagnoses. PMID:21516154

  12. Leaky ryanodine receptors contribute to diaphragmatic weakness during mechanical ventilation

    PubMed Central

    Matecki, Stefan; Dridi, Haikel; Jung, Boris; Saint, Nathalie; Reiken, Steven R.; Scheuermann, Valérie; Mrozek, Ségolène; Umanskaya, Alisa; Petrof, Basil J.; Jaber, Samir; Marks, Andrew R.; Lacampagne, Alain

    2016-01-01

    Ventilator-induced diaphragmatic dysfunction (VIDD) refers to the diaphragm muscle weakness that occurs following prolonged controlled mechanical ventilation (MV). The presence of VIDD impedes recovery from respiratory failure. However, the pathophysiological mechanisms accounting for VIDD are still not fully understood. Here, we show in human subjects and a mouse model of VIDD that MV is associated with rapid remodeling of the sarcoplasmic reticulum (SR) Ca2+ release channel/ryanodine receptor (RyR1) in the diaphragm. The RyR1 macromolecular complex was oxidized, S-nitrosylated, Ser-2844 phosphorylated, and depleted of the stabilizing subunit calstabin1, following MV. These posttranslational modifications of RyR1 were mediated by both oxidative stress mediated by MV and stimulation of adrenergic signaling resulting from the anesthesia. We demonstrate in the murine model that such abnormal resting SR Ca2+ leak resulted in reduced contractile function and muscle fiber atrophy for longer duration of MV. Treatment with β-adrenergic antagonists or with S107, a small molecule drug that stabilizes the RyR1–calstabin1 interaction, prevented VIDD. Diaphragmatic dysfunction is common in MV patients and is a major cause of failure to wean patients from ventilator support. This study provides the first evidence to our knowledge of RyR1 alterations as a proximal mechanism underlying VIDD (i.e., loss of function, muscle atrophy) and identifies RyR1 as a potential target for therapeutic intervention. PMID:27457930

  13. Hypervirulent Klebsiella pneumoniae induced ventilator-associated pneumonia in mechanically ventilated patients in China.

    PubMed

    Yan, Q; Zhou, M; Zou, M; Liu, W-e

    2016-03-01

    The purpose of this study was to investigate the clinical characteristics of hypervirulent K. pneumoniae (hvKP) induced ventilator-associated pneumonia (VAP) and the microbiological characteristics and epidemiology of the hvKP strains. A retrospective study of 49 mechanically ventilated patients with K. pneumoniae induced VAP was conducted at a university hospital in China from January 2014 to December 2014. Clinical characteristics and K. pneumoniae antimicrobial susceptibility and biofilm formation were analyzed. Genes of capsular serotypes K1, K2, K5, K20, K54 and K57 and virulence factors plasmid rmpA(p-rmpA), iroB, iucA, mrkD, entB, iutA, ybtS, kfu and allS were also evaluated. Multilocus sequence typing (MLST) and random amplified polymorphic DNA (RAPD) analyses were used to study the clonal relationship of the K. pneumoniae strains. Strains possessed p-rmpA and iroB and iucA were defined as hvKP. Of 49 patients, 14 patients (28.6 %) were infected by hvKP. Antimicrobial resistant rate was significantly higher in cKP than that in hvKP. One ST29 K54 extended-spectrum-beta-lactamase (ESBL) producing hvKP strain was detected. The prevalence of K1 and K2 in hvKP was 42.9 % and 21.4 %, respectively. The incidences of K1, K2, K20, p-rmpA, iroB, iucA, iutA, Kfu and alls were significantly higher in hvKP than those in cKP. ST23 was dominant among hvKP strains, and all the ST23 strains had identical RAPD pattern. hvKP has become a common pathogen of VAP in mechanically ventilated patients in China. Clinicians should increase awareness of hvKP induced VAP and enhance epidemiologic surveillance.

  14. Non-Invasive Ventilation in Patients with Heart Failure: A Systematic Review and Meta-Analysis

    PubMed Central

    Bittencourt, Hugo Souza; dos Reis, Helena França Correia; Lima, Melissa Santos; Gomes Neto, Mansueto

    2017-01-01

    Non-invasive ventilation (NIV) may perfect respiratory and cardiac performance in patients with heart failure (HF). The objective of the study to establish, through systematic review and meta-analysis, NIV influence on functional capacity of HF patients. A systematic review with meta-analysis of randomized studies was carried out through research of databases of Cochrane Library, SciELO, Pubmed and PEDro, using the key-words: heart failure, non-invasive ventilation, exercise tolerance; and the free terms: bi-level positive airway pressure (BIPAP), continuous positive airway pressure (CPAP), and functional capacity (terms were searched for in English and Portuguese) using the Boolean operators AND and OR. Methodological quality was ensured through PEDro scale. Weighted averages and a 95% confidence interval (CI) were calculated. The meta-analysis was done thorugh the software Review Manager, version 5.3 (Cochrane Collaboration). Four randomized clinical trials were included. Individual studies suggest NIV improved functional capacity. NIV resulted in improvement in the distance of the six-minute walk test (6MWT) (68.7m 95%CI: 52.6 to 84.9) in comparison to the control group. We conclude that the NIV is an intervention that promotes important effects in the improvement of functional capacity of HF patients. However, there is a gap in literature on which are the most adequate parameters for the application of this technique. PMID:28099587

  15. [Design of a lung simulator for teaching lung mechanics in mechanical ventilation].

    PubMed

    Heili-Frades, Sarah; Peces-Barba, Germán; Rodríguez-Nieto, María Jesús

    2007-12-01

    Over the last 10 years, noninvasive ventilation has become a treatment option for respiratory insufficiency in pulmonology services. The technique is currently included in pulmonology teaching programs. Physicians and nurses should understand the devices they use and the interaction between the patient and the ventilator in terms of respiratory mechanics, adaptation, and synchronization. We present a readily assembled lung simulator for teaching purposes that is reproducible and interactive. Based on a bag-in-box system, this model allows the concepts of respiratory mechanics in mechanical ventilation to be taught simply and graphically in that it reproduces the patterns of restriction, obstruction, and the presence of leaks. It is possible to demonstrate how each ventilation parameter acts and the mechanical response elicited. It can also readily simulate asynchrony and demonstrate how this problem can be corrected.

  16. Numerical simulation of volume-controlled mechanical ventilated respiratory system with 2 different lungs.

    PubMed

    Shi, Yan; Zhang, Bolun; Cai, Maolin; Zhang, Xiaohua Douglas

    2016-11-09

    Mechanical ventilation is a key therapy for patients who cannot breathe adequately by themselves, and dynamics of mechanical ventilation system is of great significance for life support of patients. Recently, models of mechanical ventilated respiratory system with 1 lung are used to simulate the respiratory system of patients. However, humans have 2 lungs. When the respiratory characteristics of 2 lungs are different, a single-lung model cannot reflect real respiratory system. In this paper, to illustrate dynamic characteristics of mechanical ventilated respiratory system with 2 different lungs, we propose a mathematical model of mechanical ventilated respiratory system with 2 different lungs and conduct experiments to verify the model. Furthermore, we study the dynamics of mechanical ventilated respiratory system with 2 different lungs. This research study can be used for improving the efficiency and safety of volume-controlled mechanical ventilation system.

  17. Mechanical ventilation for imaging the small animal lung.

    PubMed

    Hedlund, Laurence W; Johnson, G Allan

    2002-01-01

    This review emphasizes some of the challenges and benefits of in vivo imaging of the small animal lung. Because mechanical ventilation plays a key role in high-quality, high-resolution imaging of the small animal lung, the article focuses particularly on the problems of ventilation support, control of breathing motion and lung volume, and imaging during different phases of the breathing cycle. Solutions for these problems are discussed primarily in relation to magnetic resonance imaging, both conventional proton imaging and the newer, hyperpolarized helium imaging of pulmonary airways. Examples of applications of these imaging solutions to normal and diseased lung are illustrated in the rat and guinea pig. Although difficult to perform, pulmonary imaging in the small animal can be a valuable source of information not only for the normal lung, but also for the lung challenged by disease.

  18. Use of the virtual ventilator, a screen-based computer simulation, to teach the principles of mechanical ventilation.

    PubMed

    Keegan, Robert; Henderson, Tom; Brown, Gary

    2009-01-01

    Examination scores from 109 students enrolled in the professional veterinary program at Washington State University were evaluated to determine the effectiveness and utility of the Virtual Ventilator computer simulation for teaching the principles of mechanical ventilation in an anesthesia course. Students were randomly assigned to either a live-animal mechanical ventilation laboratory (LIVE-1st) or a computer laboratory using the mechanical ventilation simulation (SIM-1st) in week 1. During week 2, students in the LIVE-1st group participated in the ventilation simulation while students in the SIM-1st group participated in the live-animal laboratory. Student knowledge was evaluated using two similar written quizzes administered following each laboratory. Student opinions concerning the value of the simulation were assessed using an online survey. Differences in quiz scores within and between groups were compared using t-tests while survey results were tabulated. A p value of less than 0.05 was considered significant. Within the LIVE-1st group, scores for the second quiz, which was taken after the students had completed the simulation exercise, were significantly higher than those obtained from the first quiz. Accordingly, the Virtual Ventilator simulation was at least equivalent to the live-animal laboratory in the ability to present information that was subsequently tested for on the quizzes. Students in the SIM-1st group reported that use of the simulation prior to a live-animal ventilation laboratory enhanced their understanding of and ability to provide mechanical ventilation to anesthetized patients. The Virtual Ventilator simulation appears to be a useful and well-received teaching tool.

  19. Non-invasive ventilation for children with acute respiratory failure in the developing world: literature review and an implementation example.

    PubMed

    Balfour-Lynn, R E; Marsh, G; Gorayi, D; Elahi, E; LaRovere, J

    2014-06-01

    Over 2 million children die of acute respiratory infection every year, with around 98% of these deaths occurring in developing countries. Depending upon the clinical status of the patient, supplemental oxygen is usually the first line therapy. However this often proves inadequate for acute respiratory failure (ARF), in which case intubation and mechanical positive pressure ventilation are required. Adult intensive care successfully introduced non-invasive positive pressure ventilation (NIPPV) to treat ARF over a decade ago. This experience, coupled with the use of NIPPV in children with chronic respiratory insufficiency, has led to increasing use of NIPPV to treat ARF in paediatric populations. NIPPV can have similar or improved outcomes to IPPV, but with fewer complications. However there are no controlled trials of its use in children, and most data come from observational studies and retrospective reviews. In a developing world setting, where mortality from ARF is high and the risks of intubation are great and often not feasible, NIPPV can be a simple and cost-effective way to treat these patients. Its implementation in rural Northern Ghana shows NIPPV for ARF can be delivered safely with minimal training, and appears to impact significantly on mortality in those under 5 years.

  20. [Sleep-apnea syndrome, mechanical ventilation and critical care in Archivos de Bronconeumología (December 2009-December 2010)].

    PubMed

    Abad Fernández, Araceli; Pumarega, Irene Cano; Hernández, Concepción; Sampol, Gabriel; Terán-Santos, Joaquín

    2011-01-01

    The present study aims to review all the major articles on respiratory sleep disorders, mechanical ventilation, and respiratory critical care published in the last year in Archivos de bronconeumología. Between December 2009 and November 2010, 15 studies on these topics were published in Archivos de bronconeumología. Ten of these studies dealt with respiratory sleep disorders, consisting of six original articles, one special article, one review article, one letter to the editor and one supplement on chronic obstructive pulmonary disease and its association with sleep apneas. Five articles were published on non-invasive mechanical ventilation: one editorial, one special article, one article in a supplement and two original articles. As in previous years, there was a marked difference in the number of articles published on non-invasive mechanical ventilation and sleep-apnea syndrome, with a greater number of articles being published on the latter. Although some articles highlight the importance of the place where ventilation is commenced, no study specifically dealing with intermediate care units was published in Archivos de bronconeumología in 2010. This absence could be interpreted as a result of the low implantation of this type of unit in Spain, contrasting with the high activity undertaken in this field by pneumology services.

  1. Transient-state mechanisms of wind-induced burrow ventilation.

    PubMed

    Turner, J Scott; Pinshow, Berry

    2015-01-15

    Burrows are common animal habitations, yet living in a burrow presents physiological challenges for its inhabitants because the burrow isolates them from sources and sinks for oxygen, carbon dioxide, water vapor and ammonia. Conventionally, the isolation is thought to be overcome by either diffusion gas exchange within the burrow or some means of capturing wind energy to power steady or quasi-steady bulk flows of air through it. Both are examples of what may be called 'DC' models, namely steady to quasi-steady flows powered by steady to quasi-steady winds. Natural winds, however, are neither steady nor quasi-steady, but are turbulent, with a considerable portion of the energy contained in so-called 'AC' (i.e. unsteady) components, where wind velocity varies chaotically and energy to power gas exchange is stored in some form. Existing DC models of burrow gas exchange do not account for this potentially significant source of energy for ventilation. We present evidence that at least two AC mechanisms operate to ventilate both single-opening burrows (of the Cape skink, Trachylepis capensis) and double-opening model burrows (of Sundevall's jird, Meriones crassus). We propose that consideration of the physiological ecology and evolution of the burrowing habit has been blinkered by the long neglect of AC ventilation.

  2. Pleural liquid and kinetic friction coefficient of mesothelium after mechanical ventilation.

    PubMed

    Bodega, Francesca; Sironi, Chiara; Porta, Cristina; Zocchi, Luciano; Agostoni, Emilio

    2015-01-15

    Volume and protein concentration of pleural liquid in anesthetized rabbits after 1 or 3h of mechanical ventilation, with alveolar pressure equal to atmospheric at end expiration, were compared to those occurring after spontaneous breathing. Moreover, coefficient of kinetic friction between samples of visceral and parietal pleura, obtained after spontaneous or mechanical ventilation, sliding in vitro at physiological velocity under physiological load, was determined. Volume of pleural liquid after mechanical ventilation was similar to that previously found during spontaneous ventilation. This finding is contrary to expectation of Moriondo et al. (2005), based on measurement of lymphatic and interstitial pressure. Protein concentration of pleural liquid after mechanical ventilation was also similar to that occurring after spontaneous ventilation. Coefficient of kinetic friction after mechanical ventilation was 0.023±0.001, similar to that obtained after spontaneous breathing.

  3. Comparison of respiratory and hemodynamic stability in patients with traumatic brain injury ventilated by two ventilator modes: Pressure regulated volume control versus synchronized intermittent mechanical ventilation

    PubMed Central

    Aghadavoudi, Omid; Alikiaii, Babak; Sadeghi, Fariba

    2016-01-01

    Background: This study aimed to compare pressure regulated volume control (PRVC) and synchronized intermittent mechanical ventilation (SIMV) modes of ventilation according to respiratory and hemodynamic stability in patients with traumatic brain injury (TBI) admitted to Intensive Care Unit (ICU). Materials and Methods: In a randomized, single-blinded, clinical trial study, 100 patients who hospitalized in ICU due to TBI were selected and randomly divided into two groups. The first and second groups were ventilated by PRVC and SIMV modes, respectively. During mechanical ventilation, arterial blood gas and respiratory and hemodynamic parameters were also recorded and compared between the two groups. Results: According to the t-test, the mean rapid shallow breathing index (RSBI) after the first 8 h of mechanical ventilation was significantly higher in SIMV group compared with PRVC group (107.6 ± 2.75 vs. 102.2 ± 5.2, respectively, P < 0.0001). Further, according to ANOVA with repeated measures, the trend of RSBI changes had a significant difference between the two groups (P < 0.001). The trend of ratio of partial pressure arterial oxygen and fraction of inspired oxygen was different between the two groups according to Mann–Whitney–Wilcoxon test (P < 0.001). Conclusions: Using PRVC mode might be more desirable than using SIMV mode in patients with TBI due to better stability of ventilation and oxygenating. To ensure for more advantages of PRVC mode, further studies with longer follow-up and more detailed measurements are recommended. PMID:28028515

  4. Components of respiratory resistance monitored in mechanically ventilated patients.

    PubMed

    Babik, B; Peták, F; Asztalos, T; Deák, Z I; Bogáts, G; Hantos, Z

    2002-12-01

    The interrupter technique is commonly adopted to monitor respiratory resistance (Rrs,int) during mechanical ventilation; however, Rrs,int is often interpreted as an index of airway resistance (Raw). This study compared the values of Rrs,int provided by a Siemens 940 Lung Mechanics Monitor with total respiratory impedance (Zrs) parameters in 39 patients with normal spirometric parameters, who were undergoing elective coronary bypass surgery. Zrs was determined at the airway opening with pseudorandom oscillations of 0.2-6 Hz at end inspiration. Raw and tissue resistance (Rti) were derived from the Zrs data by model fitting; Rti and total resistance (Rrs,osc=Raw+Rti) were calculated at the actual respirator frequencies. Lower airway resistance (Rawl) was estimated by measuring tracheal pressure. Although good agreement was obtained between Rrs,osc and Rrs,int, with a ratio of 1.07+/-0.19 (mean+/-SD), they correlated poorly (r2=0.36). Rti and the equipment component of Raw accounted for most of Rrs,osc (39.8+/-11.9 and 43.0+/-6.9%, respectively), whereas only a small portion belonged to Rawl (17.2+/-6.3%). It is concluded that respiratory resistance may become very insensitive to changes in lower airway resistance and therefore, inappropriate for following alterations in airway tone during mechanical ventilation, especially in patients with relatively normal respiratory mechanics, where the tissue and equipment resistances represent the vast majority of the total resistance.

  5. Microbial invasions: the process, patterns, and mechanisms.

    PubMed

    Mallon, Cyrus Alexander; Elsas, Jan Dirk van; Salles, Joana Falcão

    2015-11-01

    There has recently been a surge of literature examining microbial invasions into a variety of environments. These studies often include a component of biological diversity as a major factor determining an invader's fate, yet common results are rarely cross-compared. Since many studies only present a snapshot of the entire invasion process, a bird's eye view is required to piece together the entire continuum, which we find consists of introduction, establishment, spread, and impact phases. We further examine the patterns and mechanisms associated with invasion resistance and create a mechanistic synthesis governed by the species richness, species evenness, and resource availability of resident communities. We conclude by exploring the advantages of using a theoretical invasion framework across different fields.

  6. Respiratory syncytial virus infection in children admitted to hospital but ventilated mechanically for other reasons.

    PubMed

    von Renesse, Anja; Schildgen, Oliver; Klinkenberg, Dennis; Müller, Andreas; von Moers, Arpad; Simon, Arne

    2009-01-01

    One thousand five hundred sixty-eight RSV infections were documented prospectively in 1,541 pediatric patients. Of these, 20 (1.3%) had acquired the RSV infection while treated by mechanical ventilation for reasons other than the actual RSV infection (group ventilated mechanically). The clinical characteristics of children who were infected with respiratory syncytial virus (RSV) infection while ventilated mechanically for other reasons are described and compared with a matched control group. Sixty percent of the group ventilated mechanically had at least one additional risk factor for a severe course of infection (prematurity 50%, chronic lung disease 20%, congenital heart disease 35%, immunodeficiency 20%). The median age at diagnosis in the group ventilated mechanically was 4.2 months. The matched pairs analysis (group ventilated mechanically vs. control group) revealed a higher proportion of patients with hypoxemia and apnoea in the group ventilated mechanically; more patients in the control group showed symptoms of airway obstruction (wheezing). At least one chest radiography was performed in 95% of the patients (n = 19) in the group ventilated mechanically versus 45% (n = 9) in the control group (P = 0.001). The frequency of pneumonia was 40% in the group ventilated mechanically and 20% in the control group. Despite existing consensus recommendations, only two patients (10%) of the group ventilated mechanically had received palivizumab previously. Significantly more patients in the group ventilated mechanically received antibiotic treatment (85% vs. 45%, P = 0.008), and attributable mortality was higher in the group ventilated mechanically (15% [n = 3] vs. 0% in the control group, P = 0.231). Children treated by long term mechanical ventilation may acquire RSV infection by transmission by droplets or caregivers and face an increased risk of a severe course of RSV infection. The low rate of immunoprophylaxis in this particular risk group should be improved.

  7. Effects of manual hyperinflation in preterm newborns under mechanical ventilation

    PubMed Central

    Viana, Camila Chaves; Nicolau, Carla Marques; Juliani, Regina Celia Turola Passos; de Carvalho, Werther Brunow; Krebs, Vera Lucia Jornada

    2016-01-01

    Objective To assess the effects of manual hyperinflation, performed with a manual resuscitator with and without the positive end-expiratory pressure valve, on the respiratory function of preterm newborns under mechanical ventilation. Methods Cross-sectional study of hemodynamically stable preterm newborns with gestational age of less than 32 weeks, under mechanical ventilation and dependent on it at 28 days of life. Manual hyperinflation was applied randomly, alternating the use or not of the positive end-expiratory pressure valve, followed by tracheal aspiration for ending the maneuver. For nominal data, the two-tailed Wilcoxon test was applied at the 5% significance level and 80% power. Results Twenty-eight preterm newborns, with an average birth weight of 1,005.71 ± 372.16g, an average gestational age of 28.90 ± 1.79 weeks, an average corrected age of 33.26 ± 1.78 weeks, and an average mechanical ventilation time of 29.5 (15 - 53) days, were studied. Increases in inspiratory and expiratory volumes occurred between time-points A5 (before the maneuver) and C1 (immediately after tracheal aspiration) in both the maneuver with the valve (p = 0.001 and p = 0.009) and without the valve (p = 0.026 and p = 0.001), respectively. There was also an increase in expiratory resistance between time-points A5 and C1 (p = 0.044). Conclusion Lung volumes increased when performing the maneuver with and without the valve, with a significant difference in the first minute after aspiration. There was a significant difference in expiratory resistance between the time-points A5 (before the maneuver) and C1 (immediately after tracheal aspiration) in the first minute after aspiration within each maneuver. PMID:27737427

  8. Inhibition of Janus kinase signaling during controlled mechanical ventilation prevents ventilation-induced diaphragm dysfunction.

    PubMed

    Smith, Ira J; Godinez, Guillermo L; Singh, Baljit K; McCaughey, Kelly M; Alcantara, Raniel R; Gururaja, Tarikere; Ho, Melissa S; Nguyen, Henry N; Friera, Annabelle M; White, Kathy A; McLaughlin, John R; Hansen, Derek; Romero, Jason M; Baltgalvis, Kristen A; Claypool, Mark D; Li, Wei; Lang, Wayne; Yam, George C; Gelman, Marina S; Ding, Rongxian; Yung, Stephanie L; Creger, Daniel P; Chen, Yan; Singh, Rajinder; Smuder, Ashley J; Wiggs, Michael P; Kwon, Oh-Sung; Sollanek, Kurt J; Powers, Scott K; Masuda, Esteban S; Taylor, Vanessa C; Payan, Donald G; Kinoshita, Taisei; Kinsella, Todd M

    2014-07-01

    Controlled mechanical ventilation (CMV) is associated with the development of diaphragm atrophy and contractile dysfunction, and respiratory muscle weakness is thought to contribute significantly to delayed weaning of patients. Therefore, therapeutic strategies for preventing these processes may have clinical benefit. The aim of the current study was to investigate the role of the Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) signaling pathway in CMV-mediated diaphragm wasting and weakness in rats. CMV-induced diaphragm atrophy and contractile dysfunction coincided with marked increases in STAT3 phosphorylation on both tyrosine 705 (Tyr705) and serine 727 (Ser727). STAT3 activation was accompanied by its translocation into mitochondria within diaphragm muscle and mitochondrial dysfunction. Inhibition of JAK signaling during CMV prevented phosphorylation of both target sites on STAT3, eliminated the accumulation of phosphorylated STAT3 within the mitochondria, and reversed the pathologic alterations in mitochondrial function, reduced oxidative stress in the diaphragm, and maintained normal diaphragm contractility. In addition, JAK inhibition during CMV blunted the activation of key proteolytic pathways in the diaphragm, as well as diaphragm atrophy. These findings implicate JAK/STAT3 signaling in the development of diaphragm muscle atrophy and dysfunction during CMV and suggest that the delayed extubation times associated with CMV can be prevented by inhibition of Janus kinase signaling.-Smith, I. J., Godinez, G. L., Singh, B. K., McCaughey, K. M., Alcantara, R. R., Gururaja, T., Ho, M. S., Nguyen, H. N., Friera, A. M., White, K. A., McLaughlin, J. R., Hansen, D., Romero, J. M., Baltgalvis, K. A., Claypool, M. D., Li, W., Lang, W., Yam, G. C., Gelman, M. S., Ding, R., Yung, S. L., Creger, D. P., Chen, Y., Singh, R., Smuder, A. J., Wiggs, M. P., Kwon, O.-S., Sollanek, K. J., Powers, S. K., Masuda, E. S., Taylor, V. C., Payan, D. G

  9. Inhibition of Janus kinase signaling during controlled mechanical ventilation prevents ventilation-induced diaphragm dysfunction

    PubMed Central

    Smith, Ira J.; Godinez, Guillermo L.; Singh, Baljit K.; McCaughey, Kelly M.; Alcantara, Raniel R.; Gururaja, Tarikere; Ho, Melissa S.; Nguyen, Henry N.; Friera, Annabelle M.; White, Kathy A.; McLaughlin, John R.; Hansen, Derek; Romero, Jason M.; Baltgalvis, Kristen A.; Claypool, Mark D.; Li, Wei; Lang, Wayne; Yam, George C.; Gelman, Marina S.; Ding, Rongxian; Yung, Stephanie L.; Creger, Daniel P.; Chen, Yan; Singh, Rajinder; Smuder, Ashley J.; Wiggs, Michael P.; Kwon, Oh-Sung; Sollanek, Kurt J.; Powers, Scott K.; Masuda, Esteban S.; Taylor, Vanessa C.; Payan, Donald G.; Kinoshita, Taisei; Kinsella, Todd M.

    2014-01-01

    Controlled mechanical ventilation (CMV) is associated with the development of diaphragm atrophy and contractile dysfunction, and respiratory muscle weakness is thought to contribute significantly to delayed weaning of patients. Therefore, therapeutic strategies for preventing these processes may have clinical benefit. The aim of the current study was to investigate the role of the Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) signaling pathway in CMV-mediated diaphragm wasting and weakness in rats. CMV-induced diaphragm atrophy and contractile dysfunction coincided with marked increases in STAT3 phosphorylation on both tyrosine 705 (Tyr705) and serine 727 (Ser727). STAT3 activation was accompanied by its translocation into mitochondria within diaphragm muscle and mitochondrial dysfunction. Inhibition of JAK signaling during CMV prevented phosphorylation of both target sites on STAT3, eliminated the accumulation of phosphorylated STAT3 within the mitochondria, and reversed the pathologic alterations in mitochondrial function, reduced oxidative stress in the diaphragm, and maintained normal diaphragm contractility. In addition, JAK inhibition during CMV blunted the activation of key proteolytic pathways in the diaphragm, as well as diaphragm atrophy. These findings implicate JAK/STAT3 signaling in the development of diaphragm muscle atrophy and dysfunction during CMV and suggest that the delayed extubation times associated with CMV can be prevented by inhibition of Janus kinase signaling.—Smith, I. J., Godinez, G. L., Singh, B. K., McCaughey, K. M., Alcantara, R. R., Gururaja, T., Ho, M. S., Nguyen, H. N., Friera, A. M., White, K. A., McLaughlin, J. R., Hansen, D., Romero, J. M., Baltgalvis, K. A., Claypool, M. D., Li, W., Lang, W., Yam, G. C., Gelman, M. S., Ding, R., Yung, S. L., Creger, D. P., Chen, Y., Singh, R., Smuder, A. J., Wiggs, M. P., Kwon, O.-S., Sollanek, K. J., Powers, S. K., Masuda, E. S., Taylor, V. C., Payan, D. G

  10. Home mechanical ventilation: outcomes according to remoteness from health center and different family education levels.

    PubMed

    Pekcan, Sevgi; Aslan, Ayşe Tana; Kiper, Nural; Köse, Mehmet; Cobanoglu, Nazan; Yalçin, Ebru; Doğru, Deniz; Ozçelik, Uğur

    2010-01-01

    Throughout the world, home mechanical ventilation (HMV) is being increasingly employed to treat patients suffering from chronic respiratory failure. This present study aimed to examine the characteristics and outcomes of 27 children seen in our department over a four-year period who were treated with HMV. The causes of chronic respiratory failure were as follows: 16 (59.3%) neuromuscular disease, 6 (22.2%) primary respiratory diseases, 3 (11.1%) congenital heart disease, and 2 (7.4%) storage disease. The mean age was 59.4 months (1 day-15 years); mean follow-up for invasive ventilation was 356 (0-1200) days and for non-invasive HMV was 517 (30-1440) days. With respect to maternal educational level, 13 had graduated from elementary school and 14 from high school or university. Nine of our patients resided in Ankara, while 18 lived in rural areas of Turkey. Eleven of the 27 patients died during the HMV period (1-36 months) at home. Five patients were weaned from HMV between 1-19 months. Our experience showed that HMV can be applied successfully in chronic respiratory failure patients in Turkey. Length of the follow-up period and mortality rate were not affected by the patient's place of residence (city center or rural) or maternal level of education.

  11. [Starting experience with non-invasive ventilation in paediatric intensive care unit].

    PubMed

    Vermeulen, F; de Halleux, Q; Ruiz, N; Scalfaro, P; Cotting, J; Stucki, P

    2003-10-01

    Non-invasive ventilation in pressure support (NIV) is well described in the adult and child over 5 years. However, its use in children less than 1 year of age remains anecdotal. We report our preliminary experience with the use of NIV in six children aged from 5 days to 10 months. NIV was delivered with a flow generator (VPAP IIST, Resmed Ltd, North Ryde, NSW, Australia) in association with specific tubings and a nasal mask. The use of NIV resulted in a significant decrease of both the respiratory rate (from 53 to 39 breaths per min, p < 0.01) and the PvCO(2) (from 9.33 to 6.28 kPa, p < 0.01). These results show that NIV can be used in children under 1 year of age with improvement of physiological parameters.

  12. Non-invasive ventilation for sleep-disordered breathing in Smith-Magenis syndrome.

    PubMed

    Connor, Victoria; Zhao, Sizheng; Angus, Robert

    2016-08-05

    Smith-Magenis syndrome (SMS) is a rare genetic neurodevelopmental disorder characterised by behavioural disturbances, intellectual disability and early onset obesity. The physical features of this syndrome are well characterised; however, behavioural features, such as sleep disturbance, are less well understood and difficult to manage. Sleep issues in SMS are likely due to a combination of disturbed melatonin cycle, facial anatomy and obesity-related ventilatory problems. Sleep disorders can be very distressing to patients and their families, as exemplified by our patient's experience, and can worsen behavioural issues as well as general health. This case demonstrates the successful use of non-invasive ventilation in treating underlying obesity hypoventilation syndrome and obstructive sleep apnoea. As a consequence of addressing abnormalities in sleep patterns, some behavioural problems improved.

  13. Clinical review: Humidifiers during non-invasive ventilation - key topics and practical implications

    PubMed Central

    2012-01-01

    Inadequate gas conditioning during non-invasive ventilation (NIV) can impair the anatomy and function of nasal mucosa. The resulting symptoms may have a negative effect on patients' adherence to ventilatory treatment, especially for chronic use. Several parameters, mostly technical aspects of NIV, contribute to inefficient gas conditioning. Factors affecting airway humidity during NIV include inspiratory flow, inspiratory oxygen fraction, leaks, type of ventilator, interface used to deliver NIV, temperature and pressure of inhaled gas, and type of humidifier. The correct application of a humidification system may avoid the effects of NIV-induced drying of the airway. This brief review analyses the consequences of airway dryness in patients receiving NIV and the technical tools necessary to guarantee adequate gas conditioning during ventilatory treatment. Open questions remain about the timing of gas conditioning for acute or chronic settings, the choice and type of humidification device, the interaction between the humidifier and the underlying disease, and the effects of individual humidification systems on delivered humidity. PMID:22316078

  14. Domiciliary Non-invasive Ventilation in COPD: An International Survey of Indications and Practices.

    PubMed

    Crimi, Claudia; Noto, Alberto; Princi, Pietro; Cuvelier, Antoine; Masa, Juan F; Simonds, Anita; Elliott, Mark W; Wijkstra, Peter; Windisch, Wolfram; Nava, Stefano

    2016-08-01

    Despite the fact that metanalyses and clinical guidelines do not recommend the routine use of domiciliary non-invasive ventilation (NIV) for patients diagnosed with severe stable Chronic Obstructive Pulmonary Disease (COPD) and with chronic respiratory failure, it is common practice in some countries. We conducted an international web-survey of physicians involved in provision of long-term NIV to examine patterns of domiciliary NIV use in patients diagnosed with COPD. The response rate was 41.6%. A reduction of hospital admissions, improvements in quality of life and dyspnea relief were considered as the main expected benefits for patients. Nocturnal oxygen saturation assessment was the principal procedure performed before NIV prescription. Recurrent exacerbations (>3) requiring NIV and failed weaning from in hospital NIV were the most important reasons for starting domiciliary NIV. Pressure support ventilation (PSV) was the most common mode, with "low" intensity settings (PSV-low) the most popular (44.4 ± 30.1%) compared with "high" intensity (PSV-high) strategies (26.9 ± 25.9%), with different geographical preferences. COPD is confirmed to be a common indication for domiciliary NIV. Recurrent exacerbations and failed weaning from in-hospital NIV were the main reasons for its prescription.

  15. Antipsychotic Drug Use and Screening for Delirium in Mechanically Ventilated Patients in Canadian Intensive Care Units: An Observational Study

    PubMed Central

    Thiboutot, Zoé; Perreault, Marc M; Williamson, David R; Rose, Louise; Mehta, Sangeeta; Guenette, Melanie D; Cook, Deborah; Burry, Lisa

    2016-01-01

    Background: Critically ill patients frequently experience delirium, and antipsychotic drugs are often used to manage symptoms. Objectives: To describe the use of antipsychotic drugs and delirium screening tools in mechanically ventilated, critically ill adult patients in Canadian intensive care units (ICUs) and to identify factors associated with the use of antipsychotic drugs. Methods: Pharmacists from 51 Canadian ICUs prospectively collected data on antipsychotic use and delirium screening in all patients for whom invasive mechanical ventilation was initiated during a chosen 2-week period occurring sometime in 2008 or 2009. Results: Data were collected for a total of 712 patients, of whom 115 (16.2%) received at least one dose of an antipsychotic. The antipsychotic prescribed, the total daily dose, and the administration schedule varied across sites. Delirium screening tools, validated for use in mechanically ventilated patients and endorsed by professional society guidelines, were part of routine care in a minority of ICUs (7/51 [13.7%]), and delirium screening was documented for few patients overall (41/712 patients [5.8%]). In a multivariable analysis, administration of antipsychotics was independently associated with longer duration of mechanical ventilation (odds ratio [OR] 1.12, 95% confidence interval [CI] 1.07–1.17), daily interruption of sedation (OR 1.71, 95% CI 1.01–2.90), and use of physical restraints (OR 2.15, 95% CI 1.27–3.65). Conclusion: A minority of mechanically ventilated patients in Canadian ICUs received antipsychotic drugs, and screening for delirium with validated tools was rare. Antipsychotic drug use was independently associated with longer duration of mechanical ventilation, daily interruption of sedation, and use of physical restraints. PMID:27168631

  16. Impact of tongue biofilm removal on mechanically ventilated patients

    PubMed Central

    Santos, Paulo Sérgio da Silva; Mariano, Marcelo; Kallas, Monira Samaan; Vilela, Maria Carolina Nunes

    2013-01-01

    Objective To evaluate the effectiveness of a tongue cleaner in the removal of tongue biofilm in mechanically ventilated patients. Methods Tongue biofilm and tracheal secretion samples were collected from a total of 50 patients: 27 in the study group (SG) who were intubated or tracheostomized under assisted ventilation and treated with the tongue cleaner and 23 in the control group (CG) who did not undergo tongue cleaning. Oral and tracheal secretion cultures of the SG (initially and after 5 days) and the CG (at a single time-point) were performed to evaluate the changes in bacterial flora. Results The median age of the SG patients was 77 years (45-99 years), and that of the CG patients was 79 years (21-94 years). The length of hospital stay ranged from 17-1,370 days for the SG with a median stay of 425 days and from 4-240 days for the CG with a median stay of 120 days. No significant differences were found when the dental plaque indexes were compared between the SG and the CG. There was no correlation between the index and the length of hospital stay. The same bacterial flora was found in the dental plaque of 9 of the 27 SG patients before and after the tongue scraper was used for 5 days compared with the CG (p=0.683). Overall, 7 of the 27 SG patients had positive bacterial cultures for the same strains in both tongue biofilm and tracheal secretions compared with the CG (p=0.003). Significant similarities in strain resistance and susceptibility of the assessed microorganisms were observed between oral and tracheal microflora in 6/23 cases in the CG (p=0.006). Conclusion The use of a tongue cleaner is effective at reducing tongue biofilm in patients on mechanical ventilation and facilitates oral hygiene interventions performed by caregivers. Clinical Trials Registry NCT01294943 PMID:23887759

  17. Mechanical ventilation, diaphragm weakness and weaning: A rehabilitation perspective

    PubMed Central

    Martin, A Daniel; Smith, Barbara; Gabrielli, Andrea

    2013-01-01

    Most patients are easily liberated from mechanical ventilation (MV) following resolution of respiratory failure and a successful trial of spontaneous breathing, but about 25% of patients experience difficult weaning. MV use leads to cellular changes and weakness, which has been linked to weaning difficulties and has been labeled ventilator induced diaphragm dysfunction (VIDD). Aggravating factors in human studies with prolonged weaning include malnutrition, chronic electrolyte abnormalities, hyperglycemia, excessive resistive and elastic loads, corticosteroids, muscle relaxant exposure, sepsis and compromised cardiac function. Numerous animal studies have investigated the effects of MV on diaphragm function. Virtually all of these studies have concluded that MV use rapidly leads to VIDD and have identified cellular and molecular mechanisms of VIDD. Molecular and functional studies on the effects of MV on the human diaphragm have largely confirmed the animal results and identified potential treatment strategies. Only recently have potential VIDD treatments been tested in humans, including pharmacologic interventions and diaphragm “training”. A limited number of human studies have found that specific diaphragm training can increase respiratory muscle strength in FTW patients and facilitate weaning, but larger, multicenter trials are needed. PMID:23692928

  18. Indoor Environmental Quality in Mechanically Ventilated, Energy-Efficient Buildings vs. Conventional Buildings

    PubMed Central

    Wallner, Peter; Munoz, Ute; Tappler, Peter; Wanka, Anna; Kundi, Michael; Shelton, Janie F.; Hutter, Hans-Peter

    2015-01-01

    Energy-efficient buildings need mechanical ventilation. However, there are concerns that inadequate mechanical ventilation may lead to impaired indoor air quality. Using a semi-experimental field study, we investigated if exposure of occupants of two types of buildings (mechanical vs. natural ventilation) differs with regard to indoor air pollutants and climate factors. We investigated living and bedrooms in 123 buildings (62 highly energy-efficient and 61 conventional buildings) built in the years 2010 to 2012 in Austria (mainly Vienna and Lower Austria). Measurements of indoor parameters (climate, chemical pollutants and biological contaminants) were conducted twice. In total, more than 3000 measurements were performed. Almost all indoor air quality and room climate parameters showed significantly better results in mechanically ventilated homes compared to those relying on ventilation from open windows and/or doors. This study does not support the hypothesis that occupants in mechanically ventilated low energy houses are exposed to lower indoor air quality. PMID:26561823

  19. Indoor Environmental Quality in Mechanically Ventilated, Energy-Efficient Buildings vs. Conventional Buildings.

    PubMed

    Wallner, Peter; Munoz, Ute; Tappler, Peter; Wanka, Anna; Kundi, Michael; Shelton, Janie F; Hutter, Hans-Peter

    2015-11-06

    Energy-efficient buildings need mechanical ventilation. However, there are concerns that inadequate mechanical ventilation may lead to impaired indoor air quality. Using a semi-experimental field study, we investigated if exposure of occupants of two types of buildings (mechanical vs. natural ventilation) differs with regard to indoor air pollutants and climate factors. We investigated living and bedrooms in 123 buildings (62 highly energy-efficient and 61 conventional buildings) built in the years 2010 to 2012 in Austria (mainly Vienna and Lower Austria). Measurements of indoor parameters (climate, chemical pollutants and biological contaminants) were conducted twice. In total, more than 3000 measurements were performed. Almost all indoor air quality and room climate parameters showed significantly better results in mechanically ventilated homes compared to those relying on ventilation from open windows and/or doors. This study does not support the hypothesis that occupants in mechanically ventilated low energy houses are exposed to lower indoor air quality.

  20. Regional tidal lung strain in mechanically ventilated normal lungs.

    PubMed

    Paula, Luis Felipe; Wellman, Tyler J; Winkler, Tilo; Spieth, Peter M; Güldner, Andreas; Venegas, Jose G; Gama de Abreu, Marcelo; Carvalho, Alysson R; Vidal Melo, Marcos F

    2016-12-01

    Parenchymal strain is a key determinant of lung injury produced by mechanical ventilation. However, imaging estimates of volumetric tidal strain (ε = regional tidal volume/reference volume) present substantial conceptual differences in reference volume computation and consideration of tidally recruited lung. We compared current and new methods to estimate tidal volumetric strains with computed tomography, and quantified the effect of tidal volume (VT) and positive end-expiratory pressure (PEEP) on strain estimates. Eight supine pigs were ventilated with VT = 6 and 12 ml/kg and PEEP = 0, 6, and 12 cmH2O. End-expiratory and end-inspiratory scans were analyzed in eight regions of interest along the ventral-dorsal axis. Regional reference volumes were computed at end-expiration (with/without correction of regional VT for intratidal recruitment) and at resting lung volume (PEEP = 0) corrected for intratidal and PEEP-derived recruitment. All strain estimates demonstrated vertical heterogeneity with the largest tidal strains in middependent regions (P < 0.01). Maximal strains for distinct estimates occurred at different lung regions and were differently affected by VT-PEEP conditions. Values consistent with lung injury and inflammation were reached regionally, even when global measurements were below critical levels. Strains increased with VT and were larger in middependent than in nondependent lung regions. PEEP reduced tidal-strain estimates referenced to end-expiratory lung volumes, although it did not affect strains referenced to resting lung volume. These estimates of tidal strains in normal lungs point to middependent lung regions as those at risk for ventilator-induced lung injury. The different conditions and topography at which maximal strain estimates occur allow for testing the importance of each estimate for lung injury.

  1. The optimum timing to wean invasive ventilation for patients with AECOPD or COPD with pulmonary infection

    PubMed Central

    Song, Yuanlin; Chen, Rongchang; Zhan, Qingyuan; Chen, Shujing; Luo, Zujin; Ou, Jiaxian; Wang, Chen

    2016-01-01

    COPD is characterized by a progressive decline in lung function and mental and physical comorbidities. It is a significant burden worldwide due to its growing prevalence, comorbidities, and mortality. Complication by bronchial-pulmonary infection causes 50%–90% of acute exacerbations of COPD (AECOPD), which may lead to the aggregation of COPD symptoms and the development of acute respiratory failure. Non-invasive or invasive ventilation (IV) is usually implemented to treat acute respiratory failure. However, ventilatory support (mainly IV) should be discarded as soon as possible to prevent the onset of time-dependent complications. To withdraw IV, an optimum timing has to be selected based on weaning assessment and spontaneous breathing trial or replacement of IV by non-IV at pulmonary infection control window. The former method is more suitable for patients with AECOPD without significant bronchial-pulmonary infection while the latter method is more suitable for patients with AECOPD with acute significant bronchial-pulmonary infection. PMID:27042042

  2. Weaning from mechanical ventilation: why are we still looking for alternative methods?

    PubMed

    Frutos-Vivar, F; Esteban, A

    2013-12-01

    Most patients who require mechanical ventilation for longer than 24 hours, and who improve the condition leading to the indication of ventilatory support, can be weaned after passing a first spontaneous breathing test. The challenge is to improve the weaning of patients who fail that first test. We have methods that can be referred to as traditional, such as the T-tube, pressure support or synchronized intermittent mandatory ventilation (SIMV). In recent years, however, new applications of usual techniques as noninvasive ventilation, new ventilation methods such as automatic tube compensation (ATC), mandatory minute ventilation (MMV), adaptive support ventilation or automatic weaning systems based on pressure support have been described. Their possible role in weaning from mechanical ventilation among patients with difficult or prolonged weaning remains to be established.

  3. Injurious mechanical ventilation in the normal lung causes a progressive pathologic change in dynamic alveolar mechanics

    PubMed Central

    Pavone, Lucio A; Albert, Scott; Carney, David; Gatto, Louis A; Halter, Jeffrey M; Nieman, Gary F

    2007-01-01

    Introduction Acute respiratory distress syndrome causes a heterogeneous lung injury, and without protective mechanical ventilation a secondary ventilator-induced lung injury can occur. To ventilate noncompliant lung regions, high inflation pressures are required to 'pop open' the injured alveoli. The temporal impact, however, of these elevated pressures on normal alveolar mechanics (that is, the dynamic change in alveolar size and shape during ventilation) is unknown. In the present study we found that ventilating the normal lung with high peak pressure (45 cmH20) and low positive end-expiratory pressure (PEEP of 3 cmH2O) did not initially result in altered alveolar mechanics, but alveolar instability developed over time. Methods Anesthetized rats underwent tracheostomy, were placed on pressure control ventilation, and underwent sternotomy. Rats were then assigned to one of three ventilation strategies: control group (n = 3, Pcontrol = 14 cmH2O, PEEP = 3 cmH2O), high pressure/low PEEP group (n = 6, Pcontrol = 45 cmH2O, PEEP = 3 cmH2O), and high pressure/high PEEP group (n = 5, Pcontrol = 45 cmH2O, PEEP = 10 cmH2O). In vivo microscopic footage of subpleural alveolar stability (that is, recruitment/derecruitment) was taken at baseline and than every 15 minutes for 90 minutes following ventilator adjustments. Alveolar recruitment/derecruitment was determined by measuring the area of individual alveoli at peak inspiration (I) and end expiration (E) by computer image analysis. Alveolar recruitment/derecruitment was quantified by the percentage change in alveolar area during tidal ventilation (%I – EΔ). Results Alveoli were stable in the control group for the entire experiment (low %I – EΔ). Alveoli in the high pressure/low PEEP group were initially stable (low %I – EΔ), but with time alveolar recruitment/derecruitment developed. The development of alveolar instability in the high pressure/low PEEP group was associated with histologic lung injury. Conclusion A

  4. Mechanical ventilation and lung infection in the genesis of air-space enlargement

    PubMed Central

    Sartorius, Alfonso; Lu, Qin; Vieira, Silvia; Tonnellier, Marc; Lenaour, Gilles; Goldstein, Ivan; Rouby, Jean-Jacques

    2007-01-01

    Introduction Air-space enlargement may result from mechanical ventilation and/or lung infection. The aim of this study was to assess how mechanical ventilation and lung infection influence the genesis of bronchiolar and alveolar distention. Methods Four groups of piglets were studied: non-ventilated-non-inoculated (controls, n = 5), non-ventilated-inoculated (n = 6), ventilated-non-inoculated (n = 6), and ventilated-inoculated (n = 8) piglets. The respiratory tract of intubated piglets was inoculated with a highly concentrated solution of Escherichia coli. Mechanical ventilation was maintained during 60 hours with a tidal volume of 15 ml/kg and zero positive end-expiratory pressure. After sacrifice by exsanguination, lungs were fixed for histological and lung morphometry analyses. Results Lung infection was present in all inoculated piglets and in five of the six ventilated-non-inoculated piglets. Mean alveolar and mean bronchiolar areas, measured using an analyzer computer system connected through a high-resolution color camera to an optical microscope, were significantly increased in non-ventilated-inoculated animals (+16% and +11%, respectively, compared to controls), in ventilated-non-inoculated animals (+49% and +49%, respectively, compared to controls), and in ventilated-inoculated animals (+95% and +118%, respectively, compared to controls). Mean alveolar and mean bronchiolar areas significantly correlated with the extension of lung infection (R = 0.50, p < 0.01 and R = 0.67, p < 0.001, respectively). Conclusion Lung infection induces bronchiolar and alveolar distention. Mechanical ventilation induces secondary lung infection and is associated with further air-space enlargement. The combination of primary lung infection and mechanical ventilation markedly increases air-space enlargement, the degree of which depends on the severity and extension of lung infection. PMID:17274806

  5. Quantitative investigation of alveolar structures with OCT using total liquid ventilation during mechanical ventilation

    NASA Astrophysics Data System (ADS)

    Schnabel, Christian; Gaertner, Maria; Meissner, Sven; Koch, Edmund

    2012-02-01

    To develop new treatment possibilities for patients with severe lung diseases it is crucial to understand the lung function on an alveolar level. Optical coherence tomography (OCT) in combination with intravital microscopy (IVM) are used for imaging subpleural alveoli in animal models to gain information about dynamic and morphological changes of lung tissue during mechanical ventilation. The image content suitable for further analysis is influenced by image artifacts caused by scattering, refraction, reflection, and absorbance. Because the refractive index varies with each air-tissue interface in lung tissue, these effects decrease OCT image quality exceedingly. The quality of OCT images can be increased when the refractive index inside the alveoli is matched to the one of tissue via liquid-filling. Thereby, scattering loss can be decreased and higher penetration depth and tissue contrast can be achieved. To use the advantages of liquid-filling for in vivo imaging of small rodent lungs, a suitable breathing fluid (perfluorodecalin) and a special liquid respirator are necessary. Here we show the effect of liquid-filling on OCT and IVM image quality of subpleural alveoli in a mouse model.

  6. Mechanical ventilation: past lessons and the near future

    PubMed Central

    2013-01-01

    The ability to compensate for life-threatening failure of respiratory function is perhaps the signature technology of intensive care medicine. Unchanging needs for providing effective life-support with minimized risk and optimized comfort have been, are now, and will be the principal objectives of providing mechanical ventilation. Important lessons acquired over nearly half-a-century of ICU care have brought us closer to meeting them, as technological advances in instrumentation now effectively put this hard-won knowledge into action. Rising demand in the face of economic constraints is likely to drive future innovations focused on reducing the need for user input, automating multi-element protocols, and carefully monitoring the patient for progress and complications. PMID:23514222

  7. Opioid Analgesics for Sedation and Analgesia During Mechanical Ventilation.

    PubMed

    Zeller, Brandy; Giebe, Jeanne

    2015-01-01

    Neonates are exposed to repetitive pain and stress during their stay in a NICU, which can lead to chronic complications related to their neurodevelopment and neurobehavior. Approximately 20 percent of all neonates in a NICU are intubated, mechanically ventilated, and require suctioning, which can cause both acute and chronic pain. Pain management in the neonate can be challenging. Nurses and other caregivers need to be well trained to assess pain in the neonate to effectively identify and provide appropriate pain management strategies. There is a lack of evidence to support routine administration of opiates in the neonate. As with any medication, the possibility of short- and long-term adverse reactions must be considered. Nonpharmacologic therapy should be used as much as possible.

  8. Mechanical ventilation: past lessons and the near future.

    PubMed

    Marini, John J

    2013-01-01

    The ability to compensate for life-threatening failure of respiratory function is perhaps the signature technology of intensive care medicine. Unchanging needs for providing effective life-support with minimized risk and optimized comfort have been, are now, and will be the principal objectives of providing mechanical ventilation. Important lessons acquired over nearly half-a-century of ICU care have brought us closer to meeting them, as technological advances in instrumentation now effectively put this hard-won knowledge into action. Rising demand in the face of economic constraints is likely to drive future innovations focused on reducing the need for user input, automating multi-element protocols, and carefully monitoring the patient for progress and complications.

  9. Anaesthesia ventilators

    PubMed Central

    Jain, Rajnish K; Swaminathan, Srinivasan

    2013-01-01

    Anaesthesia ventilators are an integral part of all modern anaesthesia workstations. Automatic ventilators in the operating rooms, which were very simple with few modes of ventilation when introduced, have become very sophisticated with many advanced ventilation modes. Several systems of classification of anaesthesia ventilators exist based upon various parameters. Modern anaesthesia ventilators have either a double circuit, bellow design or a single circuit piston configuration. In the bellows ventilators, ascending bellows design is safer than descending bellows. Piston ventilators have the advantage of delivering accurate tidal volume. They work with electricity as their driving force and do not require a driving gas. To enable improved patient safety, several modifications were done in circle system with the different types of anaesthesia ventilators. Fresh gas decoupling is a modification done in piston ventilators and in descending bellows ventilator to reduce th incidence of ventilator induced volutrauma. In addition to the conventional volume control mode, modern anaesthesia ventilators also provide newer modes of ventilation such as synchronised intermittent mandatory ventilation, pressure-control ventilation and pressure-support ventilation (PSV). PSV mode is particularly useful for patients maintained on spontaneous respiration with laryngeal mask airway. Along with the innumerable benefits provided by these machines, there are various inherent hazards associated with the use of the ventilators in the operating room. To use these workstations safely, it is important for every Anaesthesiologist to have a basic understanding of the mechanics of these ventilators and breathing circuits. PMID:24249886

  10. Technology for noninvasive mechanical ventilation: looking into the black box

    PubMed Central

    Navajas, Daniel; Montserrat, Josep M.

    2016-01-01

    Current devices for providing noninvasive respiratory support contain sensors and built-in intelligence for automatically modifying ventilation according to the patient's needs. These devices, including automatic continuous positive airway pressure devices and noninvasive ventilators, are technologically complex and offer a considerable number of different modes of ventilation and setting options, the details of which are sometimes difficult to capture by the user. Therefore, better predicting and interpreting the actual performance of these ventilation devices in clinical application requires understanding their functioning principles and assessing their performance under well controlled bench test conditions with simulated patients. This concise review presents an updated perspective of the theoretical basis of intelligent continuous positive airway pressure and noninvasive ventilation devices, and of the tools available for assessing how these devices respond under specific ventilation phenotypes in patients requiring breathing support. PMID:27730162

  11. Tracheomegaly and tracheosephagial fistula following mechanical ventilation: A case report and review of the literature

    PubMed Central

    Kucuk, Canan; Arda, Kemal; Ata, Naim; Turkkani, Mustafa Hamidullah; Yildiz, Özgür Ömer

    2016-01-01

    Postintubation Tracheoesophageal fistula (TEF) is a rare complication. Acquired TEF most commonly occurred following prolonged mechanical ventilation with an endotracheal or tracheostomy tube, cuff-related tracheal injury, post-intubation injury. We present a case of both tracheomegaly and tracheosephagial fistula following mechanical ventilation for 15 days, in the light of the literature. PMID:27222792

  12. Autophagy in pulmonary macrophages mediates lung inflammatory injury via NLRP3 inflammasome activation during mechanical ventilation.

    PubMed

    Zhang, Yang; Liu, Gongjian; Dull, Randal O; Schwartz, David E; Hu, Guochang

    2014-07-15

    The inflammatory response is a primary mechanism in the pathogenesis of ventilator-induced lung injury. Autophagy is an essential, homeostatic process by which cells break down their own components. We explored the role of autophagy in the mechanisms of mechanical ventilation-induced lung inflammatory injury. Mice were subjected to low (7 ml/kg) or high (28 ml/kg) tidal volume ventilation for 2 h. Bone marrow-derived macrophages transfected with a scrambled or autophagy-related protein 5 small interfering RNA were administered to alveolar macrophage-depleted mice via a jugular venous cannula 30 min before the start of the ventilation protocol. In some experiments, mice were ventilated in the absence and presence of autophagy inhibitors 3-methyladenine (15 mg/kg ip) or trichostatin A (1 mg/kg ip). Mechanical ventilation with a high tidal volume caused rapid (within minutes) activation of autophagy in the lung. Conventional transmission electron microscopic examination of lung sections showed that mechanical ventilation-induced autophagy activation mainly occurred in lung macrophages. Autophagy activation in the lungs during mechanical ventilation was dramatically attenuated in alveolar macrophage-depleted mice. Selective silencing of autophagy-related protein 5 in lung macrophages abolished mechanical ventilation-induced nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasome activation and lung inflammatory injury. Pharmacological inhibition of autophagy also significantly attenuated the inflammatory responses caused by lung hyperinflation. The activation of autophagy in macrophages mediates early lung inflammation during mechanical ventilation via NLRP3 inflammasome signaling. Inhibition of autophagy activation in lung macrophages may therefore provide a novel and promising strategy for the prevention and treatment of ventilator-induced lung injury.

  13. Long-term non-invasive ventilation therapies in children: a scoping review protocol

    PubMed Central

    Castro Codesal, Maria L; Featherstone, Robin; Martinez Carrasco, Carmen; Katz, Sherri L; Chan, Elaine Y; Bendiak, Glenda N; Almeida, Fernanda R; Young, Rochelle; Olmstead, Deborah; Waters, Karen A; Sullivan, Collin; Woolf, Vicki; Hartling, Lisa; MacLean, Joanna E

    2015-01-01

    Introduction Non-invasive ventilation (NIV) in children has become an increasingly common modality of breathing support where pressure support is delivered through a mask interface or less commonly through other non-invasive interfaces. At this time, NIV is considered a first-line option for ventilatory support of chronic respiratory insufficiency associated with a range of respiratory and sleep disorders. Previous reviews on the effectiveness, complications and adherence to NIV treatment have lacked systematic methods. The purpose of this scoping review is to provide an overview of the evidence for the use of long-term NIV in children. Methods and analysis We will use previously established scoping methodology. Ten electronic databases will be searched to identify studies in children using NIV for longer than 3 months outside an intensive care setting. Grey literature search will include conference proceedings, thesis and dissertations, unpublished trials, reports from regulatory agencies and manufacturers. Two reviewers will independently screen titles and abstracts for inclusion, followed by full-text screening of potentially relevant articles to determine final inclusion. Data synthesis will be performed at three levels: (1) an analysis of the number, publication type, publication year, and country of publication of the studies; (2) a summary of the study designs, outcomes measures used; (3) a thematic analysis of included studies by subgroups. Ethics and dissemination This study will provide a wide and rigorous overview of the evidence on the use of long-term NIV in children and provide critical information for healthcare professionals and policymakers to better care for this group of children. We will disseminate our findings through conference proceedings and publications, and evaluate the results for further systematic reviews and meta-analyses. PMID:26270951

  14. The comparison of manual and LabVIEW-based fuzzy control on mechanical ventilation.

    PubMed

    Guler, Hasan; Ata, Fikret

    2014-09-01

    The aim of this article is to develop a knowledge-based therapy for management of rats with respiratory distress. A mechanical ventilator was designed to achieve this aim. The designed ventilator is called an intelligent mechanical ventilator since fuzzy logic was used to control the pneumatic equipment according to the rat's status. LabVIEW software was used to control all equipments in the ventilator prototype and to monitor respiratory variables in the experiment. The designed ventilator can be controlled both manually and by fuzzy logic. Eight female Wistar-Albino rats were used to test the designed ventilator and to show the effectiveness of fuzzy control over manual control on pressure control ventilation mode. The anesthetized rats were first ventilated for 20 min manually. After that time, they were ventilated for 20 min by fuzzy logic. Student's t-test for p < 0.05 was applied to the measured minimum, maximum and mean peak inspiration pressures to analyze the obtained results. The results show that there is no statistical difference in the rat's lung parameters before and after the experiments. It can be said that the designed ventilator and developed knowledge-based therapy support artificial respiration of living things successfully.

  15. Lung Injury After One-Lung Ventilation: A Review of the Pathophysiologic Mechanisms Affecting the Ventilated and the Collapsed Lung.

    PubMed

    Lohser, Jens; Slinger, Peter

    2015-08-01

    Lung injury is the leading cause of death after thoracic surgery. Initially recognized after pneumonectomy, it has since been described after any period of 1-lung ventilation (OLV), even in the absence of lung resection. Overhydration and high tidal volumes were thought to be responsible at various points; however, it is now recognized that the pathophysiology is more complex and multifactorial. All causative mechanisms known to trigger ventilator-induced lung injury have been described in the OLV setting. The ventilated lung is exposed to high strain secondary to large, nonphysiologic tidal volumes and loss of the normal functional residual capacity. In addition, the ventilated lung experiences oxidative stress, as well as capillary shear stress because of hyperperfusion. Surgical manipulation and/or resection of the collapsed lung may induce lung injury. Re-expansion of the collapsed lung at the conclusion of OLV invariably induces duration-dependent, ischemia-reperfusion injury. Inflammatory cytokines are released in response to localized injury and may promote local and contralateral lung injury. Protective ventilation and volatile anesthesia lessen the degree of injury; however, increases in biochemical and histologic markers of lung injury appear unavoidable. The endothelial glycocalyx may represent a common pathway for lung injury creation during OLV, because it is damaged by most of the recognized lung injurious mechanisms. Experimental therapies to stabilize the endothelial glycocalyx may afford the ability to reduce lung injury in the future. In the interim, protective ventilation with tidal volumes of 4 to 5 mL/kg predicted body weight, positive end-expiratory pressure of 5 to 10 cm H2O, and routine lung recruitment should be used during OLV in an attempt to minimize harmful lung stress and strain. Additional strategies to reduce lung injury include routine volatile anesthesia and efforts to minimize OLV duration and hyperoxia.

  16. FAMILY PRESENCE AND SURVEILLANCE DURING WEANING FROM PROLONGED MECHANICAL VENTILATION

    PubMed Central

    Happ, Mary Beth; Swigart, Valerie A.; Tate, Judith A.; Arnold, Robert A.; Sereika, Susan M.; Hoffman, Leslie A.

    2007-01-01

    Objectives The research was designed to describe the care and communication processes during weaning from long-term mechanical ventilation (LTMV). A portion of those findings, specifically, how family members interact with the patient and respond to the ventilator and associated ICU bedside equipment during LTMV weaning, are reported here. Methods Ethnography conducted in a medical intensive care unit (MICU) and step-down MICU following 30 adults who were weaning from LTMV (> 4 days). Data collection involved field observations conducted from November 2001 to July 2003, interviews with patients, family members, and MICU clinicians, and clinical record review. Results Family members were present at the LTMV patients’ bedside during 46% of weaning trials and interacted with patients through touch, talking, and surveillance. Families’ bedside surveillance activities were interpretive of numerical monitor displays and laboratory values, protective of patient safety and comfort, and often focused exclusively on weaning. Interpretive language and surveillance were learned from and imitative of clinician behaviors. Clinicians characterized the family’s presence as helpful, a hindrance, or having no effect on the weaning process. Quantitative analysis using random coefficient modeling examining the effect of family presence on length of weaning trials showed significantly longer daily weaning trials when families were present (p < .0001). Conclusion Critical care clinicians influence families’ acquisition of interpretive surveillance skills at the bedside of patients who are weaning from LTMV. This study provides a potentially useful conceptual framework of family behaviors with long-term critically ill patients that could enhance the dialogue about family-centered care and guide future research on family presence in the ICU. PMID:17234477

  17. Predictors of impaired communication in amyotrophic lateral sclerosis patients with tracheostomy-invasive ventilation.

    PubMed

    Nakayama, Yuki; Shimizu, Toshio; Mochizuki, Yoko; Hayashi, Kentaro; Matsuda, Chiharu; Nagao, Masahiro; Watabe, Kazuhiko; Kawata, Akihiro; Oyanagi, Kiyomitsu; Isozaki, Eiji; Nakano, Imaharu

    2015-01-01

    Predictors of communication impairment in patients with amyotrophic lateral sclerosis (ALS) using tracheostomy-invasive ventilation (TIV) were investigated. Seventy-six ALS patients using TIV were enrolled and classified into three subgroups of communication ability: patients who could communicate with communication devices (Stage I), patients who had difficulty with communication (Stage II, III, or IV), and patients who could not communicate by any means (Stage V). Predictors of communication impairment were analysed by the Cox proportional hazard model. Results demonstrated that there were no significant differences in disease duration between subgroups. Within 24 months after disease onset, patients who needed TIV and tube feeding, developed oculomotor impairment or became totally quadriplegic and progressed from Stage I to II and V significantly earlier. Multivariate analyses revealed that within 24 months from onset, the need for TIV and progression to total quadriplegia were significant events in patients who progressed to Stage II, whereas the development of oculomotor limitation was significant in patients who progressed to Stage V. In conclusion, TIV, impaired oculomotor movement and total quadriplegia are predictors of severe communication impairment. Rapid disease progression might indicate future communication impairment after the use of TIV. We highly recommend early detection of impaired communication and identification of the best methods of communication.

  18. [The effectiveness of music therapy in reducing physiological and psychological anxiety in mechanically ventilated patients].

    PubMed

    Wu, Shiau-Jiun; Chou, Fan-Hao

    2008-10-01

    Anxiety, a common reaction in patients receiving ventilation therapy, often impacts negatively on patient recovery. Music therapy, a non-invasion intervention, is readily accepted by patients and has been used to relieve patient anxiety with encouraging results. The purpose of this study was to investigate the effectiveness of music therapy on reducing anxiety in patients on mechanical ventilators. An experimental design was used and all cases were collected from a medical center in southern Taiwan. While the experimental group patients took a 30-minute music therapy session, control group patients were asked to rest. Both facility anxiety and anxiety visual scales were used as research tools, with other non-invasive medical instruments employed to measure heartbeat and breathing, blood pressure and blood oxygen saturation in both patient groups. When compared with the control group, patients in the experimental group showed significant improvement in sense of anxiety (Brief Anxiety Scale, BAS, t(29) = -4.80, p < .001; Visual Analogue Anxiety Scales, VAAS, t(29) = -3.38, p = .002), diastolic pressure (t(29) = -2.74, p = .002), mean arterial pressure(t(29) = -2.26, p = .031) and breathing rate (t(29) = -4.84, p < .001). In analyzing data from the two groups, we found that the sense of anxiety (BAS, t(58) = -3.21, p = .002; VAAS, t(58) = -2.90, p = .005) and breathing rate (t(58) = -3.20, p = .002) in the experimental group decreased significantly following music therapy. Study results are hoped to serve as an important reference for clinical nursing staff. Also, it is hoped that the music therapy method may help facilitate achievement of broader humanized nursing goals.

  19. Non lineal respiratory systems mechanics simulation of acute respiratory distress syndrome during mechanical ventilation.

    PubMed

    Madorno, Matias; Rodriguez, Pablo O

    2010-01-01

    Model and simulation of biological systems help to better understand these systems. In ICUs patients often reach a complex situation where supportive maneuvers require special expertise. Among them, mechanical ventilation in patients suffering from acuter respiratory distress syndrome (ARDS) is specially challenging. This work presents a model which can be simulated and use to help in training of physicians and respiratory therapists to analyze the respiratory mechanics in this kind of patients. We validated the model in 2 ARDS patients.

  20. Mechanisms of cellular invasion by intracellular parasites.

    PubMed

    Walker, Dawn M; Oghumu, Steve; Gupta, Gaurav; McGwire, Bradford S; Drew, Mark E; Satoskar, Abhay R

    2014-04-01

    Numerous disease-causing parasites must invade host cells in order to prosper. Collectively, such pathogens are responsible for a staggering amount of human sickness and death throughout the world. Leishmaniasis, Chagas disease, toxoplasmosis, and malaria are neglected diseases and therefore are linked to socio-economical and geographical factors, affecting well-over half the world's population. Such obligate intracellular parasites have co-evolved with humans to establish a complexity of specific molecular parasite-host cell interactions, forming the basis of the parasite's cellular tropism. They make use of such interactions to invade host cells as a means to migrate through various tissues, to evade the host immune system, and to undergo intracellular replication. These cellular migration and invasion events are absolutely essential for the completion of the lifecycles of these parasites and lead to their for disease pathogenesis. This review is an overview of the molecular mechanisms of protozoan parasite invasion of host cells and discussion of therapeutic strategies, which could be developed by targeting these invasion pathways. Specifically, we focus on four species of protozoan parasites Leishmania, Trypanosoma cruzi, Plasmodium, and Toxoplasma, which are responsible for significant morbidity and mortality.

  1. [Neurally adjusted ventilatory assist: a revolution of mechanical ventilation?].

    PubMed

    Piquilloud, Lise; Jolliet, Philippe; Tassaux, Didier

    2010-12-15

    Neurally adjusted ventilatory assist or NAVA is a new assisted ventilatory mode which, in comparison with pressure support, leads to improved patient-ventilator synchrony and a more variable ventilatory pattern. It also improves arterial oxygenation. With NAVA, the electrical activity of the diaphragm is recorded through a nasogastric tube equipped with electrodes. This electrical activity is then used to pilot the ventilator. With NAVA, the patient's respiratory pattern controls the ventilator's timing of triggering and cycling as well as the magnitude of pressurization, which is proportional to inspiratory demand. The effect of NAVA on patient outcome remains to be determined through well-designed prospective studies.

  2. Brachial artery peak velocity variation to predict fluid responsiveness in mechanically ventilated patients

    PubMed Central

    2009-01-01

    Introduction Although several parameters have been proposed to predict the hemodynamic response to fluid expansion in critically ill patients, most of them are invasive or require the use of special monitoring devices. The aim of this study is to determine whether noninvasive evaluation of respiratory variation of brachial artery peak velocity flow measured using Doppler ultrasound could predict fluid responsiveness in mechanically ventilated patients. Methods We conducted a prospective clinical research in a 17-bed multidisciplinary ICU and included 38 mechanically ventilated patients for whom fluid administration was planned due to the presence of acute circulatory failure. Volume expansion (VE) was performed with 500 mL of a synthetic colloid. Patients were classified as responders if stroke volume index (SVi) increased ≥ 15% after VE. The respiratory variation in Vpeakbrach (ΔVpeakbrach) was calculated as the difference between maximum and minimum values of Vpeakbrach over a single respiratory cycle, divided by the mean of the two values and expressed as a percentage. Radial arterial pressure variation (ΔPPrad) and stroke volume variation measured using the FloTrac/Vigileo system (ΔSVVigileo), were also calculated. Results VE increased SVi by ≥ 15% in 19 patients (responders). At baseline, ΔVpeakbrach, ΔPPrad and ΔSVVigileo were significantly higher in responder than nonresponder patients [14 vs 8%; 18 vs. 5%; 13 vs 8%; P < 0.0001, respectively). A ΔVpeakbrach value >10% predicted fluid responsiveness with a sensitivity of 74% and a specificity of 95%. A ΔPPrad value >10% and a ΔSVVigileo >11% predicted volume responsiveness with a sensitivity of 95% and 79%, and a specificity of 95% and 89%, respectively. Conclusions Respiratory variations in brachial artery peak velocity could be a feasible tool for the noninvasive assessment of fluid responsiveness in patients with mechanical ventilatory support and acute circulatory failure. Trial Registration

  3. Effect of Pressure Controlled Waveforms on Flow Transport and Gas mixing in a Patient Specific Lung Model during Invasive High Frequency Oscillatory Ventilation

    NASA Astrophysics Data System (ADS)

    Alzahrany, Mohammed; Banerjee, Arindam

    2012-11-01

    A computational fluid dynamic study is carried out to investigate gas transport in patient specific human lung models (based on CT scans) during high frequency oscillatory ventilation (HFOV). Different pressure-controlled waveforms and various ventilator frequencies are studied to understand the effect of flow transport and gas mixing during these processes. Three different pressure waveforms are created by solving the equation of motion subjected to constant lung wall compliance and flow resistance. Sinusoidal, exponential and constant waveforms shapes are considered with three different frequencies 6, 10 and 15 Hz and constant tidal volume 50 ml. The velocities are calculated from the obtained flow rate and imposed as inlet flow conditions to represent the mechanical ventilation waveforms. An endotracheal tube ETT is joined to the model to account for the effect of the invasive management device with the peak Reynolds number (Re) for all the cases ranging from 6960 to 24694. All simulations are performed using high order LES turbulent model. The gas transport near the flow reversal will be discussed at different cycle phases for all the cases and a comparison of the secondary flow structures between different cases will be presented.

  4. Non-invasive Positive Pressure Ventilation during Sleep at 3800m: relationship to Acute Mountain Sickness and sleeping oxyhemoglobin saturation

    PubMed Central

    Johnson, PL; Popa, DA; Prisk, GK; Sullivan, CE; Edwards, N

    2014-01-01

    Background and objectives Ascent to high altitude results in hypobaric hypoxia and some individuals will develop Acute Mountain Sickness, which has been shown to be associated with low oxyhemoglobin saturation during sleep. Previous research has shown that positive end-expiratory pressure by use of expiratory valves in a face mask while awake, results in a reduction in AMS symptoms and higher oxyhemoglobin saturation. We aimed to test whether pressure ventilation during sleep would prevent AMS by keeping oxyhaemoglobin higher during sleep. Methods We compared sleeping oxyhemoglobin saturation and the incidence and severity of Acute Mountain Sickness in seven subjects sleeping for two consecutive nights at 3800m above sea level using either non-invasive positive pressure ventilation that delivered positive inspiratory and expiratory airway pressure via a face mask, or sleeping without assisted ventilation. The presence and severity of Acute Mountain Sickness was assessed by administration of the Lake Louise questionnaire. Results We found significant increases in the mean and minimum sleeping oxyhemoglobin saturation and decreases in AMS symptoms in subjects who used positive pressure ventilation during sleep. Mean and minimum sleeping SaO2 was lower in subjects who developed AMS after the night spent without positive pressure ventilation. Conclusion The use of positive pressure ventilation during sleep at 3800m significantly increased the sleeping oxygen saturation; we suggest that the marked reduction in symptoms of AMS is due to this higher sleeping SaO2. We agree with the findings from previous studies that the development of AMS is associated with a lower sleeping oxygen saturation. PMID:20051046

  5. Non-Invasive Ventilation in Patients with Heart Failure: A Systematic Review and Meta-Analysis.

    PubMed

    Bittencourt, Hugo Souza; Reis, Helena França Correia Dos; Lima, Melissa Santos; Gomes, Mansueto

    2017-02-01

    Non-invasive ventilation (NIV) may perfect respiratory and cardiac performance in patients with heart failure (HF). The objective of the study to establish, through systematic review and meta-analysis, NIV influence on functional capacity of HF patients. A systematic review with meta-analysis of randomized studies was carried out through research of databases of Cochrane Library, SciELO, Pubmed and PEDro, using the key-words: heart failure, non-invasive ventilation, exercise tolerance; and the free terms: bi-level positive airway pressure (BIPAP), continuous positive airway pressure (CPAP), and functional capacity (terms were searched for in English and Portuguese) using the Boolean operators AND and OR. Methodological quality was ensured through PEDro scale. Weighted averages and a 95% confidence interval (CI) were calculated. The meta-analysis was done thorugh the software Review Manager, version 5.3 (Cochrane Collaboration). Four randomized clinical trials were included. Individual studies suggest NIV improved functional capacity. NIV resulted in improvement in the distance of the six-minute walk test (6MWT) (68.7m 95%CI: 52.6 to 84.9) in comparison to the control group. We conclude that the NIV is an intervention that promotes important effects in the improvement of functional capacity of HF patients. However, there is a gap in literature on which are the most adequate parameters for the application of this technique. Resumo A ventilação não invasiva (VNI) pode aperfeiçoar o desempenho cardíaco e respiratório dos pacientes com insuficiência cardíaca (IC). O objetivo do estudo é estabelecer, por meio de revisão sistemática e meta-análise, a influência da VNI na capacidade funcional (CF) de indivíduos com IC. Foi realizada uma revisão sistemática com meta-análise de estudos randomizados através da pesquisa nas bases de dados Biblioteca Cochrane, SciELO, Pubmed e PEDro, utilizando-se as palavras-chave: insuficiência cardíaca, ventilação n

  6. Differences in the prognosis among severe trauma and medical patients requiring mechanical ventilation.

    PubMed

    Santana-Cabrera, Luciano; Sánchez-Palacios, Manuel; Rodríguez, Alina Uriarte

    2013-01-01

    Objetive. To find the differences between the prognosis of the patients with severe traumatism injury and those who were admitted with medical pathology who also required mechanical ventilation in our ICU. Patients and Method. Retrospective descriptive study in a polyvalent ICU of a third level hospital for a period of 8 years. Epidemiological variables such as age, sex, average stay, mortality, APACHE II at admission and days of mechanical ventilation, were analyzed in patients with severe traumatism injury and patients with medical pathology that were admitted in ICU and received mechanical ventilation during this period. Results. During the study period were admitted 208 patients with severe traumatism injury and 732 medical patients, all of them required mechanical ventilation. Patients with severe traumatism injury are more younger (41.8 vs 55.3 years, p = 0.001) and entered ICU in a state of minor severity, according to the prognostic index APACHE II (14.8 vs 17.4, p < 0.001), despite which they required more days of mechanical ventilation (9.8 vs 7.8 days, p = 0.017) and had a higher average stay (11.4 vs 9.4 days, p = 0.027), although the mortality was significantly lower (38.2% vs 28.2%, p = 0.005). Multivariate analysis showed as independent variables associated with mortality, the APACHE II (p < 0.0001), the average stay in ICU (p < 0.0001), days of mechanical ventilation (p < 0.0001) and type patient (p = 0.016). Conclusions. Patients with severe traumatic injury that require mechanical ventilation despite to be admitted in ICU in a state of greater severity, having an increased ICU stay and more days of mechanical ventilation, have a better prognosis than medical patients that required also mechanical ventilation at ICU stay, likely to be younger.

  7. Living with severe physical impairment, Duchenne's muscular dystrophy and home mechanical ventilation

    PubMed Central

    Dreyer, Pia S.; Steffensen, Birgit F.; Pedersen, Birthe D.

    2010-01-01

    Aim To study life-experiences of people living with Duchenne's muscular dystrophy (DMD), home mechanical ventilation (HMV) and physical impairment. Background Since the introduction of invasive HMV in the late 1980s people with DMD in Denmark live longer and have the experience of adulthood and a high degree of physical dependency. Method Nineteen patients with DMD and invasive HMV were interviewed in 2007. The interviews were recorded, transcribed verbatim and analysed according to a method inspired by Ricoeur's theory of interpretation. Findings HMV not only extended the participants lifespan, it also gave them the capacity to live an active life. They were totally dependent in everyday living, but in spite of this, they did not see themselves as physically impaired. They realised that there were activities that were physically impossible, but they considered themselves to be just the same person they had always been. This dependency was described as “independent dependency”. Conclusion The lived-experience of physical impairment is found to be “independent dependency” in an active life. To solve problems with loneliness, society needs to work with prejudice and misunderstanding and for better physical accessibility to enable full participation. PMID:20689774

  8. Predictors of Prolonged Mechanical Ventilation after Open Heart Surgery

    PubMed Central

    Totonchi, Ziae; Baazm, Farah; Chitsazan, Mitra; Seifi, Somayeh; Chitsazan, Mandana

    2014-01-01

    Introduction: Due to the importance of prolonged mechanical ventilation (PMV) as a postoperative complication, predicting "high-risk" patients by identifying predisposing risk factors is of important issue. The present study was aimed to identify perioperative variables associated with PMV in patients undergoing open heart surgery. Methods: A total of 743 consecutive patients, American Society of Anesthesiologists (ASA) physical status class III, who were scheduled to undergo open heart surgery using cardiopulmonary bypass were included in this observational study. Perioperative variables were compared between the patients with and without PMV, as defined by an extubation time of >48 h. Results: PMV occurred in 45 (6.1%) patients. On univariate analysis, pre-operative variables; including gender, history of chronic obstructive pulmonary disease (COPD); chronic kidney disease and endocarditis, intra-operative variables; including type of surgery, operation time, pump time, transfusion in operating room and postoperative variables; including bleeding and inotrope-dependency were significantly different between patients with and without PMV (all P<0.001, except for COPD and transfusion in operating room; P=0.004 and P=0.017, respectively). Conclusion: Our findings reinforce that risk stratification for predicting delayed extubation should be an important aspect of preoperative clinical evaluation in all anesthesiology settings. PMID:25610551

  9. Respiratory muscle dysfunction: a multicausal entity in the critically ill patient undergoing mechanical ventilation.

    PubMed

    Díaz, Magda C; Ospina-Tascón, Gustavo A; Salazar C, Blanca C

    2014-02-01

    Respiratory muscle dysfunction, particularly of the diaphragm, may play a key role in the pathophysiological mechanisms that lead to difficulty in weaning patients from mechanical ventilation. The limited mobility of critically ill patients, and of the diaphragm in particular when prolonged mechanical ventilation support is required, promotes the early onset of respiratory muscle dysfunction, but this can also be caused or exacerbated by other factors that are common in these patients, such as sepsis, malnutrition, advanced age, duration and type of ventilation, and use of certain medications, such as steroids and neuromuscular blocking agents. In this review we will study in depth this multicausal origin, in which a common mechanism is altered protein metabolism, according to the findings reported in various models. The understanding of this multicausality produced by the same pathophysiological mechanism could facilitate the management and monitoring of patients undergoing mechanical ventilation.

  10. Management of critical illness with non-invasive ventilation by an Australian HEMS

    PubMed Central

    Coggins, Andrew R; Cummins, Erin N; Burns, Brian

    2016-01-01

    Background Non-invasive ventilation (NIV) therapy is widely used for the management of acute respiratory failure. The objective of this study was to investigate the current use of NIV during interhospital retrievals in an Australian physician-led aeromedical service. Methods We reviewed patients receiving NIV during interhospital retrieval at the Greater Sydney Area Helicopter Medical Services (GSA-HEMS) over a 14-month period. The main objectives were to describe the number of retrievals using NIV, the need for intubation in NIV patients and the effect of the therapy on mission duration. Results Over the study period, 3018 missions were reported; 106 cases (3.51%) involved administration of NIV therapy during the retrieval. The most common indication for NIV was pneumonia (34.0%). 86/106 patients received a successful trial of NIV therapy prior to interhospital transfer. 58 patients were transferred on NIV, while 28 patients had NIV removed during transport. None of these 86 patients required intubation or died, although 17/86 ultimately required intubation within 24 hours at the receiving centre. 20/106 patients required intubation at the referring hospital after a failed trial of NIV therapy. NIV was successfully used in all available transport platforms including rotary wing. Patients receiving NIV were found to have prolonged mission durations compared with other GSA-HEMS patients (222.5 vs 193 min). This increase in mission duration was largely attributable to NIV failure, resulting in a need for Rapid Sequence Intubation at the referring hospital. Conclusions With careful patient selection, the use of interhospital NIV is feasible and appears to be safe in a retrieval system with care provided by a critical care physician. PMID:27371641

  11. The influence of mechanical ventilation on physiological parameters in ball pythons (Python regius).

    PubMed

    Jakobsen, Sashia L; Williams, Catherine J A; Wang, Tobias; Bertelsen, Mads F

    2017-02-10

    Mechanical ventilation is widely recommended for reptiles during anesthesia, and while it is well-known that their low ectothermic metabolism requires much lower ventilation than in mammals, very little is known about the influence of ventilation protocol on the recovery from anesthesia. Here, 15 ball pythons (Python regius) were induced and maintained with isoflurane for 60min at one of three ventilation protocols (30, 125, or 250mlmin(-1)kg(-1) body mass) while an arterial catheter was inserted, and ventilation was then continued on 100% oxygen at the specified rate until voluntary extubation. Mean arterial blood pressure and heart rate (HR) were measured, and arterial blood samples collected at 60, 80, 180min and 12 and 24h after intubation. In all three groups, there was evidence of a metabolic acidosis, and snakes maintained at 30mlmin(-1)kg(-1) experienced an additional respiratory acidosis, while the two other ventilation protocols resulted in normal or low arterial PCO2. In general, normal acid-base status was restored within 12h in all three protocols. HR increased by 143±64% during anesthesia with high mechanical ventilation (250mlmin(-1)kg(-1)) in comparison with recovered values. Recovery times after mechanical ventilation at 30, 125, or 250mlmin(-1)kg(-1) were 289±70, 126±16, and 68±7min, respectively. Mild overventilation may result in a faster recovery, and the associated lowering of arterial PCO2 normalised arterial pH in the face of metabolic acidosis.

  12. Awake palliative thoracic surgery in a high-risk patient: one-lung, non-invasive ventilation combined with epidural blockade.

    PubMed

    Guarracino, F; Gemignani, R; Pratesi, G; Melfi, F; Ambrosino, N

    2008-07-01

    We report the case of a terminally ill cancer patient with recurrent pericardial and bilateral pleural effusions who was scheduled for video-assisted thoracoscopic surgery. The operation was performed with the patient awake under epidural anaesthesia. The patient's cough reflex in response to lung manipulation was successfully minimised by the inhalation of aerosolised lidocaine. Video-assisted thoracic surgery requires the exclusion of a lung from ventilation. In order to support one-lung spontaneous ventilation in this high-risk patient, we successfully used non-invasive bilevel positive airway pressure ventilation via a facemask. Based on this preliminary experience, we think that critically ill patients scheduled for palliative surgery can be successfully managed with the combination of minimally invasive surgical techniques and neuraxial block with non-invasive lung ventilation.

  13. Development of an Outdoor Temperature-Based Control Algorithm for Residential Mechanical Ventilation Control

    SciTech Connect

    Less, Brennan; Walker, Iain; Tang, Yihuan

    2014-06-01

    Smart ventilation systems use controls to ventilate more during those periods that provide either an energy or IAQ advantage (or both) and less during periods that provide a dis advantage. Using detailed building simulations, this study addresses one of the simplest and lowest cost types of smart controllers —outdoor temperature- based control. If the outdoor temperature falls below a certain cut- off, the fan is simply turned off. T he main principle of smart ventilation used in this study is to shift ventilation from time periods with large indoor -outdoor temperature differences, to periods where these differences are smaller, and their energy impacts are expected to be less. Energy and IAQ performance are assessed relative to a base case of a continuously operated ventilation fan sized to comply with ASHRAE 62.2-2013 whole house ventilation requirements. In order to satisfy 62.2-2013, annual pollutant exposure must be equivalent between the temperature controlled and continuous fan cases. This requires ventilation to be greater than 62.2 requirements when the ventilation system operates. This is achieved by increasing the mechanical ventilation system air flow rates.

  14. Mechanical ventilation with the esophageal tracheal combitube (ETC) in the intensive care unit.

    PubMed Central

    Frass, M; Frenzer, R; Mayer, G; Popovic, R; Leithner, C

    1987-01-01

    Mechanical ventilation in critically ill patients is usually performed with the conventional endotracheal airway. The esophageal tracheal combitube (ETC) is a new device for cardiopulmonary resuscitation, conceived to bridge the gap between hospital and prehospital phases. The ETC may be used in esophageal and endotracheal positions. The authors report six patients who were ventilated with the ETC in the esophageal obturator position for 2-8 h after emergency ventilation. Blood gas data showed adequate ventilation with the ETC during the observation period. Data suggest that mechanical ventilation with the ETC is possible for several hours after cardiopulmonary resuscitation. This might be helpful during the initial post-arrest period, when replacement of the ETC by a conventional endotracheal airway might destabilize a vulnerable patient. PMID:3440049

  15. The Effect of Pressure-Controlled Ventilation and Volume-Controlled Ventilation in Prone Position on Pulmonary Mechanics and Inflammatory Markers.

    PubMed

    Şenay, Hasan; Sıvacı, Remziye; Kokulu, Serdar; Koca, Buğra; Bakı, Elif Doğan; Ela, Yüksel

    2016-08-01

    The aim of this present study is to compare the effect of pressure-controlled ventilation and volume-controlled ventilation on pulmonary mechanics and inflammatory markers in prone position. The study included 41 patients undergoing to vertebrae surgery. The patients were randomized into two groups: Group 1 received volume-controlled ventilation, while group 2 received pressure-controlled ventilation. The demographic data, pulmonary mechanics, the inflammatory marker levels just after the induction of anesthetics, at the 6th and 12th hours, and gas analysis from arterial blood samples taken at the beginning and the 30th minute were recorded. The inflammatory marker levels increased in both groups, without any significant difference among groups. Peak inspiratory pressure level was higher in the volume-controlled ventilation group. This study revealed that there is no difference regarding inflammatory marker levels between volume- and pressure-controlled ventilation.

  16. Characteristics and progression of children with acute viral bronchiolitis subjected to mechanical ventilation

    PubMed Central

    Ferlini, Roberta; Pinheiro, Flávia Ohlweiler; Andreolio, Cinara; Carvalho, Paulo Roberto Antonacci; Piva, Jefferson Pedro

    2016-01-01

    Objective To analyze the characteristics of children with acute viral bronchiolitis subjected to mechanical ventilation for three consecutive years and to correlate their progression with mechanical ventilation parameters and fluid balance. Methods Longitudinal study of a series of infants (< one year old) subjected to mechanical ventilation for acute viral bronchitis from January 2012 to September 2014 in the pediatric intensive care unit. The children's clinical records were reviewed, and their anthropometric data, mechanical ventilation parameters, fluid balance, clinical progression, and major complications were recorded. Results Sixty-six infants (3.0 ± 2.0 months old and with an average weight of 4.7 ± 1.4kg) were included, of whom 62% were boys; a virus was identified in 86%. The average duration of mechanical ventilation was 6.5 ± 2.9 days, and the average length of stay in the pediatric intensive care unit was 9.1 ± 3.5 days; the mortality rate was 1.5% (1/66). The peak inspiratory pressure remained at 30cmH2O during the first four days of mechanical ventilation and then decreased before extubation (25 cmH2O; p < 0.05). Pneumothorax occurred in 10% of the sample and extubation failure in 9%, which was due to upper airway obstruction in half of the cases. The cumulative fluid balance on mechanical ventilation day four was 402 ± 254mL, which corresponds to an increase of 9.0 ± 5.9% in body weight. Thirty-seven patients (56%) exhibited a weight gain of 10% or more, which was not significantly associated with the ventilation parameters on mechanical ventilation day four, extubation failure, duration of mechanical ventilation or length of stay in the pediatric intensive care unit. Conclusion The rate of mechanical ventilation for acute viral bronchiolitis remains constant, being associated with low mortality, few adverse effects, and positive cumulative fluid balance during the first days. Better fluid control might reduce the duration of mechanical

  17. Evaluation of an Incremental Ventilation Energy Model for Estimating Impacts of Air Sealing and Mechanical Ventilation

    SciTech Connect

    Logue, Jennifer M.; Turner, Willliam JN; Walker, Iain S.; Singer, Brett C.

    2012-07-01

    Changing the rate of airflow through a home affects the annual thermal conditioning energy. Large-scale changes to airflow rates of the housing stock can significantly alter the energy consumption of the residential energy sector. However, the complexity of existing residential energy models hampers the ability to estimate the impact of policy changes on a state or nationwide level. The Incremental Ventilation Energy (IVE) model developed in this study was designed to combine the output of simple airflow models and a limited set of home characteristics to estimate the associated change in energy demand of homes. The IVE model was designed specifically to enable modelers to use existing databases of home characteristics to determine the impact of policy on ventilation at a population scale. In this report, we describe the IVE model and demonstrate that its estimates of energy change are comparable to the estimates of a wellvalidated, complex residential energy model when applied to homes with limited parameterization. Homes with extensive parameterization would be more accurately characterized by complex residential energy models. The demonstration included a range of home types, climates, and ventilation systems that cover a large fraction of the residential housing sector.

  18. Transpulmonary pressure monitoring during mechanical ventilation: a bench-to-bedside review.

    PubMed

    Mietto, Cristina; Malbrain, Manu L N G; Chiumello, Davide

    2015-01-01

    Different ventilation strategies have been suggested in the past in patients with acute respiratory distress syndrome (ARDS). Airway pressure monitoring alone is inadequate to assure optimal ventilatory support in ARDS patients. The assessment of transpulmonary pressure (PTP) can help clinicians to tailor mechanical ventilation to the individual patient needs. Transpulmonary pressure monitoring, defined as airway pressure (Paw) minus intrathoracic pressure (ITP), provides essential information about chest wall mechanics and its effects on the respiratory system and lung mechanics. The positioning of an esophageal catheter is required to measure the esophageal pressure (Peso), which is clinically used as a surrogate for ITP or pleural pressure (Ppl), and calculates the transpulmonary pressure. The benefits of such a ventilation approach are avoiding excessive lung stress and individualizing the positive end-expiratory pressure (PEEP) setting. The aim is to prevent over-distention of alveoli and the cyclic recruitment/derecruitment or shear stress of lung parenchyma, mechanisms associated with ventilator-induced lung injury (VILI). Knowledge of the real lung distending pressure, i.e. the transpulmonary pressure, has shown to be useful in both controlled and assisted mechanical ventilation. In the latter ventilator modes, Peso measurement allows one to assess a patient's respiratory effort, patient-ventilator asynchrony, intrinsic PEEP and the calculation of work of breathing. Conditions that have an impact on Peso, such as abdominal hypertension, will also be discussed briefly.

  19. An Overview of the Predictor Standard Tools for Patient Weaning from Mechanical Ventilation

    PubMed Central

    Dehghani, Acieh; Abdeyazdan, Gholamhossein; Davaridolatabadi, Elham

    2016-01-01

    Most patients staying in the intensive care unit (ICU) require respiratory support through a ventilator. Since prolonged mechanical ventilation and weaning from the ventilator without criteria or at the inappropriate time can result in many complications, it is required that patients be weaned off the ventilator as soon as possible. This study was conducted to investigate a few standard tools that predict successful and timely weaning of patients from the ventilator. In the literature, SOFA and APACHE II scores, along with various tools, including Burn, Morganroth, and Corgian, have been used in weaning patients from the ventilator. In most of these studies, the increase or decrease in the APACHE II score was correlated with the patient’s weaning time, and this score could be used as a criterion for weaning. Several authors have expressed their belief that the SOFA score in the ICU is a good indicator of the prognosis of patient’s weaning from the ventilator, length of stay, mortality, and rate of recovery. Several studies have compared SOFA and APACHE II scores and have shown that there is a positive correlation between the SOFA and APACHE II scores and that both mortality and dependence on the ventilator are related to these two scores. Another tool is Burn’s weaning program. A higher Burn score indicates successful weaning off of the ventilator, successful extubation, lower length of mechanical ventilation, and shorter stay in the hospital. However, the capabilities of the Morganroth scale and the Gluck and Corgian scoring systems were evaluated only for successful weaning off of the ventilator, and a decrease in the Morganroth and Gluck scores indicated successful weaning. PMID:27054004

  20. Assisted Ventilation.

    PubMed

    Dries, David J

    2016-01-01

    Controlled Mechanical Ventilation may be essential in the setting of severe respiratory failure but consequences to the patient including increased use of sedation and neuromuscular blockade may contribute to delirium, atelectasis, and diaphragm dysfunction. Assisted ventilation allows spontaneous breathing activity to restore physiological displacement of the diaphragm and recruit better perfused lung regions. Pressure Support Ventilation is the most frequently used mode of assisted mechanical ventilation. However, this mode continues to provide a monotonous pattern of support for respiration which is normally a dynamic process. Noisy Pressure Support Ventilation where tidal volume is varied randomly by the ventilator may improve ventilation and perfusion matching but the degree of support is still determined by the ventilator. Two more recent modes of ventilation, Proportional Assist Ventilation and Neurally Adjusted Ventilatory Assist (NAVA), allow patient determination of the pattern and depth of ventilation. Proposed advantages of Proportional Assist Ventilation and NAVA include decrease in patient ventilator asynchrony and improved adaptation of ventilator support to changing patient demand. Work of breathing can be normalized with these modes as well. To date, however, a clear pattern of clinical benefit has not been demonstrated. Existing challenges for both of the newer assist modes include monitoring patients with dynamic hyperinflation (auto-positive end expiratory pressure), obstructive lung disease, and air leaks in the ventilator system. NAVA is dependent on consistent transduction of diaphragm activity by an electrode system placed in the esophagus. Longevity of effective support with this technique is unclear.

  1. Relationship between airway narrowing, patchy ventilation and lung mechanics in asthmatics.

    PubMed

    Tgavalekos, N T; Musch, G; Harris, R S; Vidal Melo, M F; Winkler, T; Schroeder, T; Callahan, R; Lutchen, K R; Venegas, J G

    2007-06-01

    Bronchoconstriction in asthma results in patchy ventilation forming ventilation defects (VDefs). Patchy ventilation is clinically important because it affects obstructive symptoms and impairs both gas exchange and the distribution of inhaled medications. The current study combined functional imaging, oscillatory mechanics and theoretical modelling to test whether the degrees of constriction of airways feeding those units outside VDefs were related to the extent of VDefs in bronchoconstricted asthmatic subjects. Positron emission tomography was used to quantify the regional distribution of ventilation and oscillatory mechanics were measured in asthmatic subjects before and after bronchoconstriction. For each subject, ventilation data was mapped into an anatomically based lung model that was used to evaluate whether airway constriction patterns, consistent with the imaging data, were capable of matching the measured changes in airflow obstruction. The degree and heterogeneity of constriction of the airways feeding alveolar units outside VDefs was similar among the subjects studied despite large inter-subject variability in airflow obstruction and the extent of the ventilation defects. Analysis of the data amongst the subjects showed an inverse relationship between the reduction in mean airway conductance, measured in the breathing frequency range during bronchoconstriction, and the fraction of lung involved in ventilation defects. The current data supports the concept that patchy ventilation is an expression of the integrated system and not just the sum of independent responses of individual airways.

  2. The use of mechanical ventilation protocols in Canadian neonatal intensive care units

    PubMed Central

    Shalish, Wissam; Anna, Guilherme Mendes Sant’

    2015-01-01

    OBJECTIVES: To identify the proportion of Canadian neonatal intensive care units with existing mechanical ventilation protocols and to determine the characteristics and respiratory care practices of units that have adopted such protocols. METHODS: A structured survey including 36 questions about mechanical ventilation protocols and respiratory care practices was mailed to the medical directors of all tertiary care neonatal units in Canada and circulated between December 2012 and March 2013. RESULTS: Twenty-four of 32 units responded to the survey (75%). Of the respondents, 91% were medical directors and 71% worked in university hospitals. Nine units (38%) had at least one type of mechanical ventilation protocol, most commonly for the acute and weaning phases. Units with pre-existing protocols were more commonly university-affiliated and had higher ratios of ventilated patients to physicians or respiratory therapists, although this did not reach statistical significance. The presence of a mechanical ventilation protocol was highly correlated with the coexistence of a protocol for noninvasive ventilation (P<0.001, OR 4.5 [95% CI 1.3 to 15.3]). There were overall wide variations in ventilation practices across units. However, units with mechanical ventilation protocols were significantly more likely to extubate neonates from the assist control mode (P=0.039, OR 8.25 [95% CI 1.2 to 59]). CONCLUSION: Despite the lack of compelling evidence to support their use in neonates, a considerable number of Canadian neonatal intensive care units have adopted mechanical ventilation protocols. More research is needed to better understand their role in reducing unnecessary variations in practice and improving short- and long-term outcomes. PMID:26038643

  3. Mechanical ventilation and sepsis impair protein metabolism in the diaphragm of neonatal pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mechanical ventilation (MV) impairs diaphragmatic function and diminishes the ability to wean from ventilatory support in adult humans. In normal neonatal pigs, animals that are highly anabolic, endotoxin (LPS) infusion induces sepsis, reduces peripheral skeletal muscle protein synthesis rates, but ...

  4. MEASUREMENT OF AMMONIA EMISSIONS FROM MECHANICALLY VENTILATED POULTRY HOUSES USING MULTIPATH TUNABLE DIODE LASER SPECTROSCOPY

    EPA Science Inventory

    Ammonia emissions from mechanically ventilated poultry operations are an important environmental concern. Open Path Tunable Diode Laser Absorption Spectroscopy has emerged as a robust real-time method for gas phase measurement of ammonia concentrations in agricultural settings. ...

  5. Tracheo-bronchitis and pneumonia associated with mechanical ventilation by Chryseobacterium indologenes.

    PubMed

    González-Castro, A; Alsasua, A; Peñasco, Y; Rodríguez, J C; Duerto, J

    2017-02-24

    The development of nosocomial infections by germs resistant to carbapenems inherently increases mortality, and causes an increase in health spending. The knowledge and study of these infections is important in improving epidemiological and therapeutic performance protocols. We present a descriptive study of eight patients diagnosed with tracheobronchitis (TAVM) and pneumonia (NAVM) associated with mechanical ventilation Chryseobacterium indologenes (CBI), over a period of five years. CBI isolation occurred at 11 days on average (rank 7-18) of remaining patients connected to mechanical ventilation. The average length of patients on mechanical ventilation was 36 days (range 10-140). The average ICU stay was 49 days (range 14-180). There was no death at 28 days, but the intra-hospital mortality was 2 cases (25%). Nosocomial respiratory infection secondary to CBI in mechanically ventilated patients has increased in recent years, so that should be included in the differential diagnostic of NAMV.

  6. Myocardial perfusion as assessed by thallium-201 scintigraphy during the discontinuation of mechanical ventilation in ventilator-dependent patients

    SciTech Connect

    Hurford, W.E.; Lynch, K.E.; Strauss, H.W.; Lowenstein, E.; Zapol, W.M. )

    1991-06-01

    Patients who cannot be separated from mechanical ventilation (MV) after an episode of acute respiratory failure often have coexisting coronary artery disease. The authors hypothesized that increased left ventricular (LV) wall stress during periods of spontaneous ventilation (SV) could alter myocardial perfusion in these patients. Using thallium-201 (201TI) myocardial scintigraphy, the authors studied the occurrence of myocardial perfusion abnormalities during periods of SV in 15 MV-dependent patients (nine women, six men; aged 71 {plus minus} 7 yr, mean {plus minus} SD). Fourteen of these patients were studied once with 201TI myocardial scintigraphy during intermittent mechanical ventilation (IMV) and again on another day, after at least 10 min of SV through a T-piece. One patient was studied during SV only. Thirteen of 14 of the patients (93%) studied during MV had abnormal patterns of initial myocardial 201TI uptake, but only 1 patient demonstrated redistribution of 201TI on delayed images. The remainder of the abnormalities observed during MV were fixed defects. SV produced significant alterations of myocardial 201TI distribution or transient LV dilation, or both, in 7 of the 15 patients (47%). Four patients demonstrated new regional decreases of LV myocardial thallium concentration with redistribution of the isotope on delayed images. The patient studied only during SV also had myocardial 201TI defects with redistribution. Five patients (3 also having areas of 201TI redistribution) had transient LV dilation during SV.

  7. Establishment of a prospective cohort of mechanically ventilated patients in five intensive care units in Lima, Peru: protocol and organisational characteristics of participating centres

    PubMed Central

    Denney, Joshua A; Capanni, Francesca; Herrera, Phabiola; Dulanto, Augusto; Roldan, Rollin; Paz, Enrique; Jaymez, Amador A; Chirinos, Eduardo E; Portugal, Jose; Quispe, Rocio; Brower, Roy G; Checkley, William

    2015-01-01

    Introduction Mechanical ventilation is a cornerstone in the management of critically ill patients worldwide; however, less is known about the clinical management of mechanically ventilated patients in low and middle income countries where limitation of resources including equipment, staff and access to medical information may play an important role in defining patient-centred outcomes. We present the design of a prospective, longitudinal study of mechanically ventilated patients in Peru that aims to describe a large cohort of mechanically ventilated patients and identify practices that, if modified, could result in improved patient-centred outcomes and lower costs. Methods and analysis Five Peruvian intensive care units (ICUs) and the Medical ICU at the Johns Hopkins Hospital were selected for this study. Eligible patients were those who underwent at least 24 h of invasive mechanical ventilation within the first 48 h of admission into the ICU. Information on ventilator settings, clinical management and treatment were collected daily for up to 28 days or until the patient was discharged from the unit. Vital status was assessed at 90 days post enrolment. A subset of participants who survived until hospital discharge were asked to participate in an ancillary study to assess vital status, and physical and mental health at 6, 12, 24 and 60 months after hospitalisation, Primary outcomes include 90-day mortality, time on mechanical ventilation, hospital and ICU lengths of stay, and prevalence of acute respiratory distress syndrome. In subsequent analyses, we aim to identify interventions and standardised care strategies that can be tailored to resource-limited settings and that result in improved patient-centred outcomes and lower costs. Ethics and dissemination We obtained ethics approval from each of the four participating hospitals in Lima, Peru, and at the Johns Hopkins School of Medicine, Baltimore, USA. Results will be disseminated as several separate

  8. Respiratory mechanics measured by forced oscillations during mechanical ventilation through a tracheal tube.

    PubMed

    Scholz, Alexander-Wigbert; Weiler, Norbert; David, Matthias; Markstaller, Klaus

    2011-05-01

    The forced oscillation technique (FOT) allows the measurement of respiratory mechanics in the intensive care setting. The aim of this study was to compare the FOT with a reference method during mechanical ventilation through a tracheal tube. The respiratory impedance spectra were measured by FOT in nine anaesthetized pigs, and resistance and compliance were estimated on the basis of a linear resistance-compliance inertance model. In comparison, resistance and compliance were quantified by the multiple linear regression analysis (LSF) of conventional ventilator waveforms to the equation of motion. The resistance of the sample was found to range from 6 to 21 cmH(2)O s l(-1) and the compliance from 12 to 32 ml cmH(2)O(-1). A Bland-Altman analysis of the resistance resulted in a sufficient agreement (bias -0.4 cmH(2)O s l(-1); standard deviation of differences 1.4 cmH(2)O s l(-1); correlation coefficient 0.93) and test-retest reliability (coefficient of variation of repeated measurements: FOT 2.1%; LSF 1.9%). The compliance, however, was poor in agreement (bias -8 ml cmH(2)O(-1), standard deviation of differences 7 ml cmH(2)O(-1), correlation coefficient 0.74) and repeatability (coefficient of variation: FOT 23%; LSF 1.7%). In conclusion, FOT provides an alternative for monitoring resistance, but not compliance, in tracheally intubated and ventilated subjects.

  9. Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control

    SciTech Connect

    Martin, E.

    2014-01-01

    The DOE Building America program has been conducting research leading to cost effective high performance homes since the early 1990's. Optimizing whole house mechanical ventilation as part of the program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this white paper is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version 7.1 (E+) and EnergyGauge USA (EGUSA). Twelve U.S. cities and five climate zones were represented. A total of 864 simulations (2*2*3*3*12= 864) were run using two building archetypes, two building leakage rates, two building orientations, three ventilation systems, three ventilation rates, and twelve climates.

  10. Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control

    SciTech Connect

    Martin, Eric

    2014-01-01

    Optimizing whole house mechanical ventilation as part of the Building Ameerica program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this report is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version 7.1 (E+) and EnergyGauge USA (EGUSA). Twelve U.S. cities and five climate zones were represented. A total of 864 simulations (2*2*3*3*12= 864) were run using two building archetypes, two building leakage rates, two building orientations, three ventilation systems, three ventilation rates, and twelve climates.

  11. Infiltration Effects on Residential Pollutant Concentrations for Continuous and Intermittent Mechanical Ventilation Approaches

    SciTech Connect

    Sherman, Max; Logue, Jennifer; Singer, Brett

    2010-06-01

    The prevailing residential ventilation standard in North America, American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 62.2, specifies volumetric airflow requirements as a function of the overall size of the home and the number of bedrooms, assumes a fixed, minimal amount of infiltration, and requires mechanical ventilation to achieve the remainder. The standard allows for infiltration credits and intermittent ventilation patterns that can be shown to provide comparable performance. Whole-house ventilation methods have a substantial effect on time-varying indoor pollutant concentrations. If alternatives specified by Standard 62.2, such as intermittent ventilation, are used, short-term pollutant concentrations could exceed acute health standards even if chronic health standards are met.The authors present a methodology for comparing ASHRAE- and non-ASHRAE-specified ventilation scenarios on relative indoor pollutant concentrations. We use numerical modeling to compare the maximum time-averaged concentrations for acute exposure relevant (1-hour, 8-hour, 24-hour ) and chronic exposure relevant (1-year) time periods for four different ventilation scenarios in six climates with a range of normalized leakage values. The results suggest that long-term concentrations are the most important metric for assessing the effectiveness of whole-house ventilation systems in meeting exposure standards and that, if chronic health exposure standards are met, acute standards will also be met.

  12. Recent advances in mechanical ventilation in patients without acute respiratory distress syndrome

    PubMed Central

    Filho, Roberto R.; Rocha, Leonardo L.; Schultz, Marcus J.

    2014-01-01

    While being an essential part of general anesthesia for surgery and at times even a life-saving intervention in critically ill patients, mechanical ventilation has a strong potential to cause harm. Certain ventilation strategies could prevent, at least to some extent, the injury caused by this intervention. One essential element of so-called ‘lung-protective’ ventilation is the use of lower tidal volumes. It is uncertain whether higher levels of positive end-expiratory pressures have lung-protective properties as well. There are indications that too high oxygen fractions of inspired air, or too high blood oxygen targets, are harmful. Circumstantial evidence further suggests that spontaneous modes of ventilation are to be preferred over controlled ventilation to prevent harm to respiratory muscle. Finally, the use of restrictive sedation strategies in critically ill patients indirectly prevents ventilation-induced injury, as daily spontaneous awakening and breathing trials and bolus instead of continuous sedation are associated with shorter duration of ventilation and shorten the exposure to the injurious effects of ventilation. PMID:25580269

  13. Effect of early mobilization on discharge disposition of mechanically ventilated patients

    PubMed Central

    Ota, Hideki; Kawai, Hideki; Sato, Makoto; Ito, Kazuaki; Fujishima, Satoshi; Suzuki, Hiroko

    2015-01-01

    [Purpose] The purpose of this study was to clarify the benefits of early mobilization for mechanically ventilated patients for their survival to discharge to home from the hospital. [Subjects and Methods] Medical records were retrospectively analyzed of patients who satisfied the following criteria: age ≥ 18 years; performance status 0–2 and independent living at their home before admission; mechanical ventilation for more than 48 h; and survival after mechanical ventilation. Mechanically ventilated patients in the early mobilization (EM) group (n = 48) received mobilization therapy, limb exercise and chest physiotherapy, whereas those in the control group (n = 60) received bed rest alone. Univariate and multivariate logistic regression analyses were performed to identify clinical variables associated with discharge disposition. [Results] Early mobilization was a positive independent factor and the presence of neurological deficits was a negative factor contributing to discharge to home. Among patients surviving mechanical ventilation without neurological deficits, the rate of discharge to home was significantly higher among patients in the EM group that in the control group (76% vs. 40%). [Conclusion] Early mobilization can improve the rate of discharge to home of patients requiring mechanical ventilation because of non-neurological deficits. PMID:25931747

  14. Non-invasive ventilation in obesity hypoventilation syndrome without severe obstructive sleep apnoea

    PubMed Central

    Masa, Juan F; Corral, Jaime; Caballero, Candela; Barrot, Emilia; Terán-Santos, Joaquin; Alonso-Álvarez, Maria L; Gomez-Garcia, Teresa; González, Mónica; López-Martín, Soledad; De Lucas, Pilar; Marin, José M; Marti, Sergi; Díaz-Cambriles, Trinidad; Chiner, Eusebi; Egea, Carlos; Miranda, Erika; Mokhlesi, Babak; García-Ledesma, Estefanía; Sánchez-Quiroga, M-Ángeles; Ordax, Estrella; González-Mangado, Nicolás; Troncoso, Maria F; Martinez-Martinez, Maria-Ángeles; Cantalejo, Olga; Ojeda, Elena; Carrizo, Santiago J; Gallego, Begoña; Pallero, Mercedes; Ramón, M Antonia; Díaz-de-Atauri, Josefa; Muñoz-Méndez, Jesús; Senent, Cristina; Sancho-Chust, Jose N; Ribas-Solís, Francisco J; Romero, Auxiliadora; Benítez, José M; Sanchez-Gómez, Jesús; Golpe, Rafael; Santiago-Recuerda, Ana; Gomez, Silvia; Bengoa, Mónica

    2016-01-01

    Background Non-invasive ventilation (NIV) is an effective form of treatment in patients with obesity hypoventilation syndrome (OHS) who have concomitant severe obstructive sleep apnoea (OSA). However, there is a paucity of evidence on the efficacy of NIV in patients with OHS without severe OSA. We performed a multicentre randomised clinical trial to determine the comparative efficacy of NIV versus lifestyle modification (control group) using daytime arterial carbon dioxide tension (PaCO2) as the main outcome measure. Methods Between May 2009 and December 2014 we sequentially screened patients with OHS without severe OSA. Participants were randomised to NIV versus lifestyle modification and were followed for 2 months. Arterial blood gas parameters, clinical symptoms, health-related quality of life assessments, polysomnography, spirometry, 6-min walk distance test, blood pressure measurements and healthcare resource utilisation were evaluated. Statistical analysis was performed using intention-to-treat analysis. Results A total of 365 patients were screened of whom 58 were excluded. Severe OSA was present in 221 and the remaining 86 patients without severe OSA were randomised. NIV led to a significantly larger improvement in PaCO2 of −6 (95% CI −7.7 to −4.2) mm Hg versus −2.8 (95% CI −4.3 to −1.3) mm Hg, (p<0.001) and serum bicarbonate of −3.4 (95% CI −4.5 to −2.3) versus −1 (95% CI −1.7 to −0.2 95% CI)  mmol/L (p<0.001). PaCO2 change adjusted for NIV compliance did not further improve the inter-group statistical significance. Sleepiness, some health-related quality of life assessments and polysomnographic parameters improved significantly more with NIV than with lifestyle modification. Additionally, there was a tendency towards lower healthcare resource utilisation in the NIV group. Conclusions NIV is more effective than lifestyle modification in improving daytime PaCO2, sleepiness and polysomnographic parameters. Long

  15. The Association of Fever with Total Mechanical Ventilation Time in Critically Ill Patients

    PubMed Central

    Yokoyama, Takeshi

    2016-01-01

    This research aims to investigate the impact of fever on total mechanical ventilation time (TVT) in critically ill patients. Subgroup analysis was conducted using a previous prospective, multicenter observational study. We included mechanically ventilated patients for more than 24 hours from 10 Korean and 15 Japanese intensive care units (ICU), and recorded maximal body temperature under the support of mechanical ventilation (MAXMV). To assess the independent association of MAXMV with TVT, we used propensity-matched analysis in a total of 769 survived patients with medical or surgical admission, separately. Together with multiple linear regression analysis to evaluate the association between the severity of fever and TVT, the effect of MAXMV on ventilator-free days was also observed by quantile regression analysis in all subjects including non-survivors. After propensity score matching, a MAXMV ≥ 37.5°C was significantly associated with longer mean TVT by 5.4 days in medical admission, and by 1.2 days in surgical admission, compared to those with MAXMV of 36.5°C to 37.4°C. In multivariate linear regression analysis, patients with three categories of fever (MAXMV of 37.5°C to 38.4°C, 38.5°C to 39.4°C, and ≥ 39.5°C) sustained a significantly longer duration of TVT than those with normal range of MAXMV in both categories of ICU admission. A significant association between MAXMV and mechanical ventilator-free days was also observed in all enrolled subjects. Fever may be a detrimental factor to prolong TVT in mechanically ventilated patients. These findings suggest that fever in mechanically ventilated patients might be associated with worse mechanical ventilation outcome. PMID:27822946

  16. Mechanics of ventilation in swellsharks, Cephaloscyllium ventriosum (Scyliorhinidae).

    PubMed

    Ferry-Graham, L A

    1999-06-01

    A simple two-pump model has served to describe the mechanics of ventilation in cartilaginous and bony fishes since the pioneering work of G. M. Hughes. A hallmark of this model is that water flow over the gills is continuous. Studies of feeding kinematics in the swellshark Cephaloscyllium ventriosum, however, suggested that a flow reversal occurred during prey capture and transport. Given that feeding is often considered to be simply an exaggeration of the kinematic events performed during respiration, I investigated whether flow reversals are potentially present during respiration. Pressure and impedance data were coupled with kinematic data from high-speed video footage and dye studies and used to infer patterns of water flow through the heads of respiring swellsharks. Swellsharks were implanted with pressure transducers to determine the pattern and magnitude of pressures generated within the buccal and parabranchial (gill) cavities during respiration. Pressure traces revealed extended periods of pressure reversal during the respiratory cycle. Further, impedance data suggested that pressures within the buccal and parabranchial cavities were not generated by the cyclic opening and closing of the jaws and gills in the manner previously suggested by Hughes. Thus, the classic model needs to be re-evaluated to determine its general applicability. Two alternative models for pressure patterns and their mechanism of generation during respiration are provided. The first depicts a double-reversal scenario common in the swellshark whereby pressures are reversed following both of the pump stages (the suction pump and the pressure pump) rather than after the pressure-pump stage only. The second model describes a scenario in which the suction pump is insufficient for generating a positive pressure differential across the gills; thus, a pressure reversal persists throughout this phase of respiration. Kinematic analysis based on high-speed video footage and dye studies, however

  17. Survey of operating theatre ventilation facilities for minimally invasive surgery in Great Britain and Northern Ireland: current practice and considerations for the future.

    PubMed

    Smyth, E T M; Humphreys, H; Stacey, A; Taylor, E W; Hoffman, P; Bannister, G

    2005-10-01

    Increasing use of minimally invasive surgery (MIS) and other invasive procedures has raised the question of what ventilation facilities are appropriate for such procedures to prevent infection. The Hospital Infection Society (HIS) Working Party on Infection Control in Operating Theatres undertook a survey of practice in Great Britain and Northern Ireland on the ventilation facilities provided for a variety of MIS and other procedures. Five hundred and fifty questionnaires were forwarded to HIS members, and 186 (39%) replies were received. Fifty-eight percent were from district general hospitals (DGHs). Designated theatres for orthopaedic surgery (although not necessarily ultraclean ventilated theatres) were available in more than 80% of hospitals, with approximately 50% of hospitals having designated theatres for a variety of other surgical subspecialities. Approximately two-thirds of urological procedures were performed in conventionally ventilated operating theatres. Most radiological procedures were performed in non-ventilated theatres or treatment rooms. In around half of the DGHs and university/referral hospitals, orthopaedic MIS procedures such as arthroscopy were performed in ultraclean ventilated theatres. This survey revealed considerable variation in the use of conventionally ventilated theatres and ultraclean ventilated theatres. In particular, many radiological and anaesthetic procedures are performed in treatment rooms or ventilated rooms with less than 20 air changes per hour. Whilst it is not clear whether this is acceptable practice given current knowledge, large-scale clinical trials to determine what standards of ventilation are appropriate to minimize infection for these types of procedures would be difficult to conduct. Research is needed on the relative risk of airborne infection for a variety of procedures, including whether all prosthetic implant procedures should be carried out in ultraclean ventilated theatres, as infection associated with

  18. [Long-term effects of home mechanical ventilation with positive pressure using a nasal mask].

    PubMed

    Escarrabill, J; Estopà, R; Robert, D; Casolivé, V; Manresa, F

    1991-10-05

    Home mechanical ventilation (HMV) is an efficient alternative in the treatment of patients with chronic respiratory failure secondary to restrictive mechanical disorders (neuromuscular disease, such as Duchenne's disease, thorax deformities due to kyphoscoliosis or tuberculosis sequelae). The case of a patient with severe kyphoscoliosis in the phase of chronic respiratory failure (PaO2 34 mmHg and PaCO2 61 mmHg, breathing ambient air) is presented in which, following the failure of negative pressure mechanical ventilation ("poncho"), positive pressure ventilation was tested with a silicon made-to-measure nasal mask as the access via. Adaptation to HMV was good with the patient using the ventilation nightly. Following 12 months of treatment the patient is able to carry out everyday activities and arterial gasometry breathing ambient air is PaO2 77 mmHg and PaCO2 43 mmHg.

  19. Measured Air Distribution Effectiveness for Residential Mechanical Ventilation Systems

    SciTech Connect

    Sherman, Max; Sherman, Max H.; Walker, Iain S.

    2008-05-01

    The purpose of ventilation is dilute or remove indoor contaminants that an occupant is exposed to. In a multi-zone environment such as a house, there will be different dilution rates and different source strengths in every zone. Most US homes have central HVAC systems, which tend to mix the air thus the indoor conditions between zones. Different types of ventilation systems will provide different amounts of exposure depending on the effectiveness of their air distribution systems and the location of sources and occupants. This paper will report on field measurements using a unique multi-tracer measurement system that has the capacity to measure not only the flow of outdoor air to each zone, but zone-to-zone transport. The paper will derive seven different metrics for the evaluation of air distribution. Measured data from two homes with different levels of natural infiltration will be used to evaluate these metrics for three different ASHRAE Standard 62.2 compliant ventilation systems. Such information can be used to determine the effectiveness of different systems so that appropriate adjustments can be made in residential ventilation standards such as ASHRAE Standard 62.2.

  20. Total Liquid Ventilation Provides Superior Respiratory Support to Conventional Mechanical Ventilation in a Large Animal Model of Severe Respiratory Failure

    PubMed Central

    Pohlmann, Joshua R; Brant, David O; Daul, Morgan A; Reoma, Junewai L; Kim, Anne C; Osterholzer, Kathryn R; Johnson, Kent J; Bartlett, Robert H; Cook, Keith E; Hirschl, Ronald B

    2011-01-01

    Total liquid ventilation (TLV) has the potential to provide respiratory support superior to conventional mechanical ventilation (CMV) in the acute respiratory distress syndrome (ARDS). However, laboratory studies are limited to trials in small animals for no longer than 4 hours. The objective of this study was to compare TLV and CMV in a large animal model of ARDS for 24 hours. Ten sheep weighing 53 ± 4 (SD) kg were anesthetized and ventilated with 100% oxygen. Oleic acid was injected into the pulmonary circulation until PaO2:FiO2 ≥ 60 mmHg, followed by transition to a protective CMV protocol (n=5) or TLV (n=5) for 24 hours. Pathophysiology was recorded and the lungs were harvested for histological analysis. Animals treated with CMV became progressively hypoxic and hypercarbic despite maximum ventilatory support. Sheep treated with TLV maintained normal blood gases with statistically greater PO2 (p<10−9) and lower PCO2 (p < 10−3) than the CMV group. Survival at 24 hours in the TLV and CMV groups were 100% and 40% respectively (p< 0.05). Thus, TLV provided gas exchange superior to CMV in this laboratory model of severe ARDS. PMID:21084968

  1. Total liquid ventilation provides superior respiratory support to conventional mechanical ventilation in a large animal model of severe respiratory failure.

    PubMed

    Pohlmann, Joshua R; Brant, David O; Daul, Morgan A; Reoma, Junewai L; Kim, Anne C; Osterholzer, Kathryn R; Johnson, Kent J; Bartlett, Robert H; Cook, Keith E; Hirschl, Ronald B

    2011-01-01

    Total liquid ventilation (TLV) has the potential to provide respiratory support superior to conventional mechanical ventilation (CMV) in the acute respiratory distress syndrome (ARDS). However, laboratory studies are limited to trials in small animals for no longer than 4 hours. The objective of this study was to compare TLV and CMV in a large animal model of ARDS for 24 hours. Ten sheep weighing 53 ± 4 (SD) kg were anesthetized and ventilated with 100% oxygen. Oleic acid was injected into the pulmonary circulation until PaO2:FiO2 ≤ 60 mm Hg, followed by transition to a protective CMV protocol (n = 5) or TLV (n = 5) for 24 hours. Pathophysiology was recorded, and the lungs were harvested for histological analysis. Animals treated with CMV became progressively hypoxic and hypercarbic despite maximum ventilatory support. Sheep treated with TLV maintained normal blood gases with statistically greater PO2 (p < 10(-9)) and lower PCO2 (p < 10(-3)) than the CMV group. Survival at 24 hours in the TLV and CMV groups were 100% and 40%, respectively (p < 0.05). Thus, TLV provided gas exchange superior to CMV in this laboratory model of severe ARDS.

  2. Efficiency and outcome of non-invasive versus invasive positive pressure ventilation therapy in respiratory failure due to chronic obstructive pulmonary disease.

    PubMed Central

    Amri Maleh, Valiollah; Monadi, Mahmood; Heidari, Behzad; Maleh, Parviz Amri; Bijani, Ali

    2016-01-01

    Background: Application noninvasive ventilation in the patients with exacerbation of chronic obstructive pulmonary disease (COPD) reduced mortality. This case-control study was designed to compare efficiency and outcome of non-invasive (NIV) versus invasive positive pressure ventilation (IPPV) in respiratory failure due to COPD. Methods: The patients were assigned to NIV or IPPV intermittantly.The clinical parameters, including RR (respiratory rate), BP (blood pressure), HR (heart rate) and PH, PaCO2, PaO2 before and 1, 4 and 24 h after treatment were measured. Demographic information such as age, sex, severity of disease based on APACHE score, length of stay and outcome were recorded. Results: Fifty patients were enrolled in the NIV group and 50 patients in IPPV. The mean age was 70.5 in NIV and 63.9 in invasive ventilation group (p>0.05). In IPPV group, the average values of PH: PCO2: and PO2, were 7.22±0.11, 69.64 + 24.25: and 68.86±24.41 .In NIV, the respective values were 7.30±0.07, 83.94±18.95, and 60.60±19.88. In NIV group, after 1, 4 and 24 h treatment, the clinical and ventilation parameters were stable. The mean APACHE score in was IPPV, 26.46±5.45 and in NIV was 12.26±5.54 (p<0.05). The average length of hospital stay in IPPV was 15.90±10 and in NIV 8.12±6.49 days (p<0.05). The total mortality in the NIV was 4 (8%) and in IPPV, 27 patients (54%) (p<0.05). Conclusion: This study indicates that using NIPPV is a useful therapeutic mode of treatment for respiratory failure with acceptable success rate and lower mortality. The application of NIPPV reduces hospital stay, intubation and its consequent complications. PMID:27386061

  3. Particle Size Concentration Distribution and Influences on Exhaled Breath Particles in Mechanically Ventilated Patients

    PubMed Central

    Chen, Yi-Fang; Huang, Sheng-Hsiu; Wang, Yu-Ling; Chen, Chun-Wan

    2014-01-01

    Humans produce exhaled breath particles (EBPs) during various breath activities, such as normal breathing, coughing, talking, and sneezing. Airborne transmission risk exists when EBPs have attached pathogens. Until recently, few investigations had evaluated the size and concentration distributions of EBPs from mechanically ventilated patients with different ventilation mode settings. This study thus broke new ground by not only evaluating the size concentration distributions of EBPs in mechanically ventilated patients, but also investigating the relationship between EBP level and positive expiratory end airway pressure (PEEP), tidal volume, and pneumonia. This investigation recruited mechanically ventilated patients, with and without pneumonia, aged 20 years old and above, from the respiratory intensive care unit of a medical center. Concentration distributions of EBPs from mechanically ventilated patients were analyzed with an optical particle analyzer. This study finds that EBP concentrations from mechanically ventilated patients during normal breathing were in the range 0.47–2,554.04 particles/breath (0.001–4.644 particles/mL). EBP concentrations did not differ significantly between the volume control and pressure control modes of the ventilation settings in the mechanically ventilated patients. The patient EBPs were sized below 5 µm, and 80% of them ranged from 0.3 to 1.0 µm. The EBPs concentrations in patients with high PEEP (> 5 cmH2O) clearly exceeded those in patients with low PEEP (≤ 5 cmH2O). Additionally, a significant negative association existed between pneumonia duration and EBPs concentration. However, tidal volume was not related to EBPs concentration. PMID:24475230

  4. Predictors of extubation failure and reintubation in newborn infants subjected to mechanical ventilation

    PubMed Central

    Costa, Ana Cristina de Oliveira; Schettino, Renata de Carvalho; Ferreira, Sandra Clecêncio

    2014-01-01

    Objective To identify risk factors for extubation failure and reintubation in newborn infants subjected to mechanical ventilation and to establish whether ventilation parameters and blood gas analysis behave as predictors of those outcomes. Methods Prospective study conducted at a neonatal intensive care unit from May to November 2011. A total of 176 infants of both genders subjected to mechanical ventilation were assessed after extubation. Extubation failure was defined as the need to resume mechanical ventilation within less than 72 hours. Reintubation was defined as the need to reintubate the infants any time after the first 72 hours. Results Based on the univariate analysis, the variables gestational age <28 weeks, birth weight <1,000g and low Apgar scores were associated with extubation failure and reintubation. Based on the multivariate analysis, the variables length of mechanical ventilation (days), potential of hydrogen (pH) and partial pressure of oxygen (pO2) remained associated with extubation failure, and the five-minute Apgar score and age at extubation were associated with reintubation. Conclusion Low five-minute Apgar scores, age at extubation, length of mechanical ventilation, acid-base disorders and hyperoxia exhibited associations with the investigated outcomes of extubation failure and reintubation. PMID:24770689

  5. Noninvasive Mechanical Ventilation in Acute Respiratory Failure Patients: A Respiratory Therapist Perspective

    PubMed Central

    Hidalgo, V; Giugliano-Jaramillo, C; Pérez, R; Cerpa, F; Budini, H; Cáceres, D; Gutiérrez, T; Molina, J; Keymer, J; Romero-Dapueto, C

    2015-01-01

    Physiotherapist in Chile and Respiratory Therapist worldwide are the professionals who are experts in respiratory care, in mechanical ventilation (MV), pathophysiology and connection and disconnection criteria. They should be experts in every aspect of the acute respiratory failure and its management, they and are the ones who in medical units are able to resolve doubts about ventilation and the setting of the ventilator. Noninvasive mechanical ventilation should be the first-line of treatment in acute respiratory failure, and the standard of care in severe exacerbations of chronic obstructive pulmonary disease, acute cardiogenic pulmonary edema, and in immunosuppressed patients with high levels of evidence that support the work of physiotherapist. Exist other considerations where most of the time, physicians and other professionals in the critical units do not take into account when checking the patient ventilator synchrony, such as the appropriate patient selection, ventilator selection, mask selection, mode selection, and the selection of a trained team in NIMV. The physiotherapist needs to evaluate bedside; if patients are properly connected to the ventilator and in a synchronously manner. In Chile, since 2004, the physioterapist are included in the guidelines as a professional resource in the ICU organization, with the same skills and obligations as those described in the literature for respiratory therapists. PMID:26312104

  6. Noninvasive Mechanical Ventilation in Acute Respiratory Failure Patients: A Respiratory Therapist Perspective.

    PubMed

    Hidalgo, V; Giugliano-Jaramillo, C; Pérez, R; Cerpa, F; Budini, H; Cáceres, D; Gutiérrez, T; Molina, J; Keymer, J; Romero-Dapueto, C

    2015-01-01

    Physiotherapist in Chile and Respiratory Therapist worldwide are the professionals who are experts in respiratory care, in mechanical ventilation (MV), pathophysiology and connection and disconnection criteria. They should be experts in every aspect of the acute respiratory failure and its management, they and are the ones who in medical units are able to resolve doubts about ventilation and the setting of the ventilator. Noninvasive mechanical ventilation should be the first-line of treatment in acute respiratory failure, and the standard of care in severe exacerbations of chronic obstructive pulmonary disease, acute cardiogenic pulmonary edema, and in immunosuppressed patients with high levels of evidence that support the work of physiotherapist. Exist other considerations where most of the time, physicians and other professionals in the critical units do not take into account when checking the patient ventilator synchrony, such as the appropriate patient selection, ventilator selection, mask selection, mode selection, and the selection of a trained team in NIMV. The physiotherapist needs to evaluate bedside; if patients are properly connected to the ventilator and in a synchronously manner. In Chile, since 2004, the physioterapist are included in the guidelines as a professional resource in the ICU organization, with the same skills and obligations as those described in the literature for respiratory therapists.

  7. Liver displacement during ventilation in Thiel embalmed human cadavers - a possible model for research and training in minimally invasive therapies.

    PubMed

    Eisma, Roos; Gueorguieva, Mariana; Immel, Erwin; Toomey, Rachel; McLeod, Graeme; Soames, Roger; Melzer, Andreas

    2013-09-01

    Respiration-related movement of organs is a complication in a range of diagnostic and interventional procedures. The development and validation of techniques to compensate for such movement requires appropriate models. Human cadavers embalmed with the Thiel method remain flexible and could provide a suitable model. In this study liver displacement during ventilation was assessed in eight Thiel embalmed cadavers, all of which showed thoracic and abdominal motion. Four cadavers displayed realistic lung behaviour, one showed some signs of pneumothorax after prolonged ventilation, one had limited filling of the lungs, and two displayed significant leakage of air into the thorax. A coronal slice containing the largest section through the liver was imaged with a real-time Fast Gradient Echo (FGR) MRI sequence: Craniocaudal displacement of the liver was then determined from a time-series of slices. The maximum liver displacement observed in the cadavers ranged from 7 to 35 mm. The ventilation applied was comparable to tidal breathing at rest and the results found for liver displacement are similar to values in the literature for respiratory motion of the liver under similar conditions. This indicates that Thiel embalmed cadavers have potential as a model for research and training in minimally invasive procedures.

  8. Comparison of Chemical and Mechanical Prophylaxis of Venous Thromboembolism in Nonsurgical Mechanically Ventilated Patients

    PubMed Central

    Gaspard, Dany; Vito, Karen; Schorr, Christa; Hunter, Krystal; Gerber, David

    2015-01-01

    Background. Thromboembolic events are major causes of morbidity, and prevention is important. We aimed to compare chemical prophylaxis (CP) and mechanical prophylaxis (MP) as methods of prevention in nonsurgical patients on mechanical ventilation. Methods. We performed a retrospective study of adult patients admitted to the Cooper University Hospital ICU between 2002 and 2010. Patients on one modality of prophylaxis throughout their stay were included. The CP group comprised 329 patients and the MP group 419 patients. The primary outcome was incidence of thromboembolic events. Results. Acuity measured by APACHE II score was comparable between the two groups (p = 0.215). Univariate analysis showed 1 DVT/no PEs in the CP group and 12 DVTs/1 PE in the MP group (p = 0.005). Overall mortality was 34.3% and 50.6%, respectively. ICU LOS was similar. Hospital LOS was shorter in the MP group. Multivariate analysis showed a significantly higher incidence of events in the MP prophylaxis group (odds ratio 9.9). After excluding patients admitted for bleeding in both groups, repeat analysis showed again increased events in the MP group (odds ratio 2.9) but this result did not reach statistical significance. Conclusion. Chemical methods for DVT/PE prophylaxis seem superior to mechanical prophylaxis in nonsurgical patients on mechanical ventilation and should be used when possible. PMID:26682067

  9. Minimally invasive endoscopic port-access intracardiac surgery with one lung ventilation: impact on gas exchange and anaesthesia resources.

    PubMed

    Kottenberg-Assenmacher, E; Kamler, M; Peters, J

    2007-03-01

    Minimally invasive endoscopic intracardiac surgery including one lung ventilation has been proposed to decrease surgical trauma but its impact on oxygenation and resource consumption has not been reported. We compared effects on gas exchange, induction, total anaesthesia time, staffing costs, and complications in 42 consecutive patients to a matched group undergoing similar surgery conventionally. Use of endoscopic compared to conventional surgery evoked a decrease in the P(a)o(2)/F(I)o(2) ratio (mean (SD) 24.1 (14.9) vs 48.9 (14) kPa, p < 0.05) following termination of bypass with one lung ventilation (10 patients showed a P(a)o(2)/F(i)o(2) below 13.3 kPa (100 mmHg)). There was also an increase of anaesthesia induction time (47 (13) vs 31 (9) min, p < 0.05), and an increase by 156 min of total anaesthesia time (474 (89) vs 321 (69) min, p < 0.05). Anaesthetist staffing costs increased by 300%. Thus, minimally invasive endoscopic intracardiac surgery consumes many more anaesthesia resources than conventional surgery and can result in hypoxaemia, but overall can be considered feasible provided that extensive continuous monitoring is employed.

  10. Open Lung Biopsy Among Critically Ill, Mechanically Ventilated Patients. A Metaanalysis

    PubMed Central

    Walkey, Allan J.

    2015-01-01

    Rationale: Open lung biopsy may be performed to guide therapy in mechanically ventilated patients with diagnostic uncertainty regarding etiology of pulmonary infiltrates. Current evidence for open lung biopsy in mechanically ventilated patients comes from single-center case series. Objectives: We performed a metaanalysis of case series to determine diagnoses, complications, and changes in therapy after lung biopsy in critically ill patients requiring mechanical ventilation. Methods: We searched Medline for case series of lung biopsies in critically ill patients requiring mechanical ventilation. We pooled results of individual case series using random effects metaanalysis models to obtain summary proportions. Measurements and Main Results: We identified 14 case series including a total of 512 mechanically ventilated patients with 530 histopathological diagnoses. The most common diagnoses were “fibrosis/pneumonitis” (n = 155, 25%; 95% confidence interval [CI], 14–37%) and infection (n = 113, 20%; 95% CI, 15–27%). Viruses were the most commonly identified infectious etiology identified on open lung biopsy, representing 50% of potential pathogens. Diffuse alveolar damage was present in a minority of specimens (n = 100, 16%; 95% CI, 8–25%). Therapeutic changes after lung biopsy occurred in 399 patients (78%; 95% CI, 64–81%). Procedure-related complications occurred in 29% of patients (95% CI, 25–33%), most commonly persistent air leak. Mortality among mechanically ventilated patients after diagnostic open lung biopsy was 54%. Conclusions: Among mechanically ventilated patients with respiratory failure of unclear etiology, lung biopsy yielded a wide range of diagnoses and was associated with a change in therapy in most patients. PMID:26065712

  11. The rapid shallow breathing index as a predictor of successful mechanical ventilation weaning: clinical utility when calculated from ventilator data

    PubMed Central

    de Souza, Leonardo Cordeiro; Lugon, Jocemir Ronaldo

    2015-01-01

    ABSTRACT OBJECTIVE: The use of the rapid shallow breathing index (RSBI) is recommended in ICUs, where it is used as a predictor of mechanical ventilation (MV) weaning success. The aim of this study was to compare the performance of the RSBI calculated by the traditional method (described in 1991) with that of the RSBI calculated directly from MV parameters. METHODS: This was a prospective observational study involving patients who had been on MV for more than 24 h and were candidates for weaning. The RSBI was obtained by the same examiner using the two different methods (employing a spirometer and the parameters from the ventilator display) at random. In comparing the values obtained with the two methods, we used the Mann-Whitney test, Pearson's linear correlation test, and Bland-Altman plots. The performance of the methods was compared by evaluation of the areas under the ROC curves. RESULTS: Of the 109 selected patients (60 males; mean age, 62 ± 20 years), 65 were successfully weaned, and 36 died. There were statistically significant differences between the two methods for respiratory rate, tidal volume, and RSBI (p < 0.001 for all). However, when the two methods were compared, the concordance and the intra-observer variation coefficient were 0.94 (0.92-0.96) and 11.16%, respectively. The area under the ROC curve was similar for both methods (0.81 ± 0.04 vs. 0.82 ± 0.04; p = 0.935), which is relevant in the context of this study. CONCLUSIONS: The satisfactory performance of the RSBI as a predictor of weaning success, regardless of the method employed, demonstrates the utility of the method using the mechanical ventilator. PMID:26785962

  12. Experimental studies on the airflow characteristics of spaces with mechanical ventilation

    SciTech Connect

    Chow, W.K.; Fung, W.Y.

    1997-12-31

    Ventilation in the occupied zone was studied experimentally in the waiting area of nine railway concourses in Hong Kong. The performance of the mechanical ventilation systems in those areas was also evaluated by studying the age of air, local air velocity, and carbon dioxide level. The results show that ventilation effectiveness may not necessarily be improved with increasing supply or extraction flow rate. The revised jet momentum numbers for those stations are also calculated and compared with the mean carbon dioxide concentration and the local age of air. It appears that this parameter can be used for evaluating the performance of the ventilation systems. A linear relation is fitted empirically to correlate the mean local age of air with the revised jet momentum number for the nine stations.

  13. Randomised controlled trial of respiratory system compliance measurements in mechanically ventilated neonates

    PubMed Central

    Stenson, B.; Glover, R.; Wilkie, R.; Laing, I.; Tarnow-Mordi, W.

    1998-01-01

    AIM—To determine whether outcomes of neonatal mechanical ventilation could be improved by regular pulmonary function testing.
METHODS—Two hundred and forty five neonates, without immediately life threatening congenital malformations, were mechanically ventilated in the newborn period. Infants were randomly allocated to conventional clinical management (control group) or conventional management supplemented by regular measurements of static respiratory system compliance, using the single breath technique, with standardised management advice based on the results.
RESULTS—Fifty five (45%) infants in each group experienced one or more adverse outcomes. The median (quartile) durations of ventilation and oxygen supplementation were 5 (2-12) and 6 (2-34) days for the control group, and 4 (2-9) and 6 (3-36) days for the experimental group (not significant). On post-hoc secondary analysis, control group survivors were ventilated for 1269 days with a median (quartile) of 5 (2-13) days, and experimental group survivors were ventilated for 775 days with a median (quartile) duration of 3 (2-8) days (p=0.03).
CONCLUSIONS—Although primary analysis did not show any substantial benefit associated with regular measurement of static respiratory system compliance, this may reflect a type II error, and a moderate benefit has not been excluded. Larger studies are required to establish the value of on-line monitoring techniques now available with neonatal ventilators.

 PMID:9536834

  14. A new system for continuous and remote monitoring of patients receiving home mechanical ventilation

    NASA Astrophysics Data System (ADS)

    Battista, L.

    2016-09-01

    Home mechanical ventilation is the treatment of patients with respiratory failure or insufficiency by means of a mechanical ventilator at a patient's home. In order to allow remote patient monitoring, several tele-monitoring systems have been introduced in the last few years. However, most of them usually do not allow real-time services, as they have their own proprietary communication protocol implemented and some ventilation parameters are not always measured. Moreover, they monitor only some breaths during the whole day, despite the fact that a patient's respiratory state may change continuously during the day. In order to reduce the above drawbacks, this work reports the development of a novel remote monitoring system for long-term, home-based ventilation therapy; the proposed system allows for continuous monitoring of the main physical quantities involved during home-care ventilation (e.g., differential pressure, volume, and air flow rate) and is developed in order to allow observations of different remote therapy units located in different places of a city, region, or country. The developed remote patient monitoring system is able to detect various clinical events (e.g., events of tube disconnection and sleep apnea events) and has been successfully tested by means of experimental tests carried out with pulmonary ventilators typically used to support sick patients.

  15. Effect of Antipyretic Therapy on Mortality in Critically Ill Patients with Sepsis Receiving Mechanical Ventilation Treatment

    PubMed Central

    Ye, Sheng; Xu, Dan; Zhang, Chenmei; Li, Mengyao

    2017-01-01

    Purpose. The study aimed to investigate the effectiveness of antipyretic therapy on mortality in critically ill patients with sepsis requiring mechanical ventilation. Methods. In this study, we employed the multiparameter intelligent monitoring in intensive care II (MIMIC-II) database (version 2.6). All patients meeting the criteria for sepsis and also receiving mechanical ventilation treatment were included for analysis, all of whom suffer from fever or hyperthermia. Logistic regression model and R language (R version 3.2.3 2015-12-10) were used to explore the association of antipyretic therapy and mortality risk in critically ill patients with sepsis receiving mechanical ventilation treatment. Results. A total of 8,711 patients with mechanical ventilator were included in our analysis, and 1523 patients died. We did not find any significant difference in the proportion of patients receiving antipyretic medication between survivors and nonsurvivors (7.9% versus 7.4%, p = 0.49). External cooling was associated with increased risk of death (13.5% versus 9.5%, p < 0.001). In our regression model, antipyretic therapy was positively associated with mortality risk (odds ratio [OR]: 1.41, 95% CI: 1.20–1.66, p < 0.001). Conclusions. The use of antipyretic therapy is associated with increased risk of mortality in septic ICU patients requiring mechanical ventilation. External cooling may even be deleterious. PMID:28386165

  16. Assessment of Indoor Air Quality Benefits and Energy Costs of Mechanical Ventilation

    SciTech Connect

    Logue, J.M.; Price, P.N.; Sherman, M.H.; Singer, B.C.

    2011-07-01

    Intake of chemical air pollutants in residences represents an important and substantial health hazard. Sealing homes to reduce air infiltration can save space conditioning energy, but can also increase indoor pollutant concentrations. Mechanical ventilation ensures a minimum amount of outdoor airflow that helps reduce concentrations of indoor emitted pollutants while requiring some energy for fan(s) and thermal conditioning of the added airflow. This work demonstrates a physics based, data driven modeling framework for comparing the costs and benefits of whole-house mechanical ventilation and applied the framework to new California homes. The results indicate that, on a population basis, the health benefits from reduced exposure to indoor pollutants in New California homes are worth the energy costs of adding mechanical ventilation as specified by ASHRAE Standard 62.2.This study determines the health burden for a subset of pollutants in indoor air and the costs and benefits of ASHRAE's mechanical ventilation standard (62.2) for new California homes. Results indicate that, on a population basis, the health benefits of new home mechanical ventilation justify the energy costs.

  17. Pulmonary blood flow distribution in sheep: effects of anesthesia, mechanical ventilation, and change in posture

    NASA Technical Reports Server (NTRS)

    Walther, S. M.; Domino, K. B.; Glenny, R. W.; Hlastala, M. P.

    1997-01-01

    BACKGROUND: Recent studies providing high-resolution images of pulmonary perfusion have questioned the classical zone model of pulmonary perfusion. Hence the present work was undertaken to provide detailed maps of regional pulmonary perfusion to examine the influence of anesthesia, mechanical ventilation, and posture. METHODS: Pulmonary perfusion was analyzed with intravenous fluorescent microspheres (15 microm) in six sheep studied in four conditions: prone and awake, prone with pentobarbital-anesthesia and breathing spontaneously, prone with anesthesia and mechanical ventilation, and supine with anesthesia and mechanical ventilation. Lungs were air dried at total lung capacity and sectioned into approximately 1,100 pieces (about 2 cm3) per animal. The pieces were weighed and assigned spatial coordinates. Fluorescence was read on a spectrophotometer, and signals were corrected for piece weight and normalized to mean flow. Pulmonary blood flow heterogeneity was assessed using the coefficient of variation of flow data. RESULTS: Pentobarbital anesthesia and mechanical ventilation did not influence perfusion heterogeneity, but heterogeneity increased when the animals were in the supine posture (P < 0.01). Gravitational flow gradients were absent in the prone position but present in the supine (P < 0.001 compared with zero). Pulmonary perfusion was distributed with a hilar-to-peripheral gradient in animals breathing spontaneously (P < 0.05). CONCLUSIONS: The influence of pentobarbital anesthesia and mechanical ventilation on pulmonary perfusion heterogeneity is small compared with the effect of changes in posture. Analysis of flow gradients indicate that gravity plays a small role in determining pulmonary blood flow distribution.

  18. Changes in respiratory mechanics during respiratory physiotherapy in mechanically ventilated patients

    PubMed Central

    Moreira, Fernanda Callefe; Teixeira, Cassiano; Savi, Augusto; Xavier, Rogério

    2015-01-01

    Objective To evaluate the changes in ventilatory mechanics and hemodynamics that occur in patients dependent on mechanical ventilation who are subjected to a standard respiratory therapy protocol. Methods This experimental and prospective study was performed in two intensive care units, in which patients dependent on mechanical ventilation for more than 48 hours were consecutively enrolled and subjected to an established respiratory physiotherapy protocol. Ventilatory variables (dynamic lung compliance, respiratory system resistance, tidal volume, peak inspiratory pressure, respiratory rate, and oxygen saturation) and hemodynamic variables (heart rate) were measured one hour before (T-1), immediately after (T0) and one hour after (T+1) applying the respiratory physiotherapy protocol. Results During the period of data collection, 104 patients were included in the study. Regarding the ventilatory variables, an increase in dynamic lung compliance (T-1 = 52.3 ± 16.1mL/cmH2O versus T0 = 65.1 ± 19.1mL/cmH2O; p < 0.001), tidal volume (T-1 = 550 ± 134mL versus T0 = 698 ± 155mL; p < 0.001), and peripheral oxygen saturation (T-1 = 96.5 ± 2.29% versus T0 = 98.2 ± 1.62%; p < 0.001) were observed, in addition to a reduction of respiratory system resistance (T-1 = 14.2 ± 4.63cmH2O/L/s versus T0 = 11.0 ± 3.43cmH2O/L/s; p < 0.001), after applying the respiratory physiotherapy protocol. All changes were present in the assessment performed one hour (T+1) after the application of the respiratory physiotherapy protocol. Regarding the hemodynamic variables, an immediate increase in the heart rate after application of the protocol was observed, but that increase was not maintained (T-1 = 88.9 ± 18.7 bpm versus T0 = 93.7 ± 19.2bpm versus T+1 = 88.5 ± 17.1bpm; p < 0.001). Conclusion Respiratory therapy leads to immediate changes in the lung mechanics and hemodynamics of mechanical ventilation-dependent patients, and ventilatory changes are likely to remain for at least one hour

  19. The role of spontaneous effort during mechanical ventilation: normal lung versus injured lung.

    PubMed

    Yoshida, Takeshi; Uchiyama, Akinori; Fujino, Yuji

    2015-01-01

    The role of preserving spontaneous effort during mechanical ventilation and its interaction with mechanical ventilation have been actively investigated for several decades. Inspiratory muscle activities can lower the pleural components surrounding the lung, leading to an increase in transpulmonary pressure when spontaneous breathing effort is preserved during mechanical ventilation. Thus, increased transpulmonary pressure provides various benefits for gas exchange, ventilation pattern, and lung aeration. However, it is important to note that these beneficial effects of preserved spontaneous effort have been demonstrated only when spontaneous effort is modest and lung injury is less severe. Recent studies have revealed the 'dark side' of spontaneous effort during mechanical ventilation, especially in severe lung injury. The 'dark side' refers to uncontrollable transpulmonary pressure due to combined high inspiratory pressure with excessive spontaneous effort and the injurious lung inflation pattern of Pendelluft (i.e., the translocation of air from nondependent lung regions to dependent lung regions). Thus, during the early stages of severe ARDS, the strict control of transpulmonary pressure and prevention of Pendelluft should be achieved with the short-term use of muscle paralysis. When there is preserved spontaneous effort in ARDS, spontaneous effort should be maintained at a modest level, as the transpulmonary pressure and the effect size of Pendelluft depend on the intensity of the spontaneous effort.

  20. Music preferences of mechanically ventilated patients participating in a randomized controlled trial.

    PubMed

    Heiderscheit, Annie; Breckenridge, Stephanie J; Chlan, Linda L; Savik, Kay

    2014-01-01

    Mechanical ventilation (MV) is a life-saving measure and supportive modality utilized to treat patients experiencing respiratory failure. Patients experience pain, discomfort, and anxiety as a result of being mechanically ventilated. Music listening is a non-pharmacological intervention used to manage these psychophysiological symptoms associated with mechanical ventilation. The purpose of this secondary analysis was to examine music preferences of 107 MV patients enrolled in a randomized clinical trial that implemented a patient-directed music listening protocol to help manage the psychophysiological symptom of anxiety. Music data presented includes the music genres and instrumentation patients identified as their preferred music. Genres preferred include: classical, jazz, rock, country, and oldies. Instrumentation preferred include: piano, voice, guitar, music with nature sounds, and orchestral music. Analysis of three patients' preferred music received throughout the course of the study is illustrated to demonstrate the complexity of assessing MV patients and the need for an ongoing assessment process.

  1. Music preferences of mechanically ventilated patients participating in a randomized controlled trial

    PubMed Central

    Heiderscheit, Annie; Breckenridge, Stephanie J.; Chlan, Linda L.; Savik, Kay

    2014-01-01

    Mechanical ventilation (MV) is a life-saving measure and supportive modality utilized to treat patients experiencing respiratory failure. Patients experience pain, discomfort, and anxiety as a result of being mechanically ventilated. Music listening is a non-pharmacological intervention used to manage these psychophysiological symptoms associated with mechanical ventilation. The purpose of this secondary analysis was to examine music preferences of 107 MV patients enrolled in a randomized clinical trial that implemented a patient-directed music listening protocol to help manage the psychophysiological symptom of anxiety. Music data presented includes the music genres and instrumentation patients identified as their preferred music. Genres preferred include: classical, jazz, rock, country, and oldies. Instrumentation preferred include: piano, voice, guitar, music with nature sounds, and orchestral music. Analysis of three patients’ preferred music received throughout the course of the study is illustrated to demonstrate the complexity of assessing MV patients and the need for an ongoing assessment process. PMID:25574992

  2. Non-invasive detection of respiratory muscles activity during assisted ventilation.

    PubMed

    Heyer, Laurent; Baconnier, Pierre F; Eberhard, André; Biot, Loïc; Viale, Jean-Paul; Perdrix, Jean-Pierre; Carry, Pierre-Yves

    2002-04-01

    The instantaneous pressure applied by the respiratory muscles [Pmus(t)] of a patient under ventilatory support may be continuously assessed with the help of a model of the passive respiratory system updated cycle by cycle. Inspiratory activity (IA) is considered present when Pmus goes below a given threshold. In six patients, we compared IA with (i) inspiratory activity (IAref) obtained from esophageal pressure and diaphragmatic EMG and (ii) that (IAvent) detected by the ventilator. In any case, a ventilator support onset coincides with an IA onset but the opposite is not true. IA onset is always later than IAref beginning ((0.21 +/- 0.10 s) and IA end always precedes IAref end (0.46 +/- 0.16 s). These results clearly deteriorate when the model is not updated.

  3. Hyperpolarized 3He magnetic resonance imaging ventilation defects in asthma: relationship to airway mechanics.

    PubMed

    Leary, Del; Svenningsen, Sarah; Guo, Fumin; Bhatawadekar, Swati; Parraga, Grace; Maksym, Geoffrey N

    2016-04-01

    In patients with asthma, magnetic resonance imaging (MRI) provides direct measurements of regional ventilation heterogeneity, the etiology of which is not well-understood, nor is the relationship of ventilation abnormalities with lung mechanics. In addition, respiratory resistance and reactance are often abnormal in asthmatics and the frequency dependence of respiratory resistance is thought to reflect ventilation heterogeneity. We acquiredMRIventilation defect maps, forced expiratory volume in one-second (FEV1), and airways resistance (Raw) measurements, and used a computational airway model to explore the relationship of ventilation defect percent (VDP) with simulated measurements of respiratory system resistance (Rrs) and reactance (Xrs).MRIventilation defect maps were experimentally acquired in 25 asthmatics before, during, and after methacholine challenge and these were nonrigidly coregistered to the airway tree model. Using the model coregistered to ventilation defect maps, we narrowed proximal (9th) and distal (14th) generation airways that were spatially related to theMRIventilation defects. The relationships forVDPwith Raw measured using plethysmography (r = 0.79), and model predictions of Rrs>14(r = 0.91,P < 0.0001) and Rrs>9(r = 0.88,P < 0.0001) were significantly stronger (P = 0.005;P = 0.03, respectively) than withFEV1(r = -0.68,P = 0.0001). The slopes for the relationship ofVDPwith simulated lung mechanics measurements were different (P < 0.0001); among these, the slope for theVDP-Xrs0.2relationship was largest, suggesting thatVDPwas dominated by peripheral airway heterogeneity in these patients. In conclusion, as a first step toward understanding potential links between lung mechanics and ventilation defects, impedance predictions were made using a computational airway tree model with simulated constriction of airways related to ventilation defects measured in mild-moderate asthmatics.

  4. Chest compression with a higher level of pressure support ventilation: effects on secretion removal, hemodynamics, and respiratory mechanics in patients on mechanical ventilation*

    PubMed Central

    Naue, Wagner da Silva; Forgiarini, Luiz Alberto; Dias, Alexandre Simões; Vieira, Silvia Regina Rios

    2014-01-01

    OBJECTIVE: To determine the efficacy of chest compression accompanied by a 10-cmH2O increase in baseline inspiratory pressure on pressure support ventilation, in comparison with that of aspiration alone, in removing secretions, normalizing hemodynamics, and improving respiratory mechanics in patients on mechanical ventilation. METHODS: This was a randomized crossover clinical trial involving patients on mechanical ventilation for more than 48 h in the ICU of the Porto Alegre Hospital de Clínicas, in the city of Porto Alegre, Brazil. Patients were randomized to receive aspiration alone (control group) or compression accompanied by a 10-cmH2O increase in baseline inspiratory pressure on pressure support ventilation (intervention group). We measured hemodynamic parameters, respiratory mechanics parameters, and the amount of secretions collected. RESULTS: We included 34 patients. The mean age was 64.2 ± 14.6 years. In comparison with the control group, the intervention group showed a higher median amount of secretions collected (1.9 g vs. 2.3 g; p = 0.004), a greater increase in mean expiratory tidal volume (16 ± 69 mL vs. 56 ± 69 mL; p = 0.018), and a greater increase in mean dynamic compliance (0.1 ± 4.9 cmH2O vs. 2.8 ± 4.5 cmH2O; p = 0.005). CONCLUSIONS: In this sample, chest compression accompanied by an increase in pressure support significantly increased the amount of secretions removed, the expiratory tidal volume, and dynamic compliance. (ClinicalTrials.gov Identifier:NCT01155648 [http://www.clinicaltrials.gov/]) PMID:24626270

  5. The Influence of Fluid Overload on the Length of Mechanical Ventilation in Pediatric Congenital Heart Surgery.

    PubMed

    Sampaio, Tatiana Z A L; O'Hearn, Katie; Reddy, Deepti; Menon, Kusum

    2015-12-01

    Fluid overload and prolonged mechanical ventilation lead to worse outcomes in critically ill children. However, the association between these variables in children following congenital heart surgery is unknown. The objectives of this study were to describe the association between fluid overload and duration of mechanical ventilation, oxygen requirement and radiologic findings of pulmonary and chest wall edema. This study is a retrospective chart review of patients who underwent congenital heart surgery between June 2010 and December 2013. Univariate and multivariate associations between maximum cumulative fluid balance and length of mechanical ventilation and OI were tested using the Spearman correlation test and multiple linear regression models, respectively. There were 85 eligible patients. Maximum cumulative fluid balance was associated with duration of mechanical ventilation (adjusted analysis beta coefficient = 0.53, CI 0.38-0.66, P < 0.001), length of stay in the pediatric intensive care unit (Spearman's correlation = 0.45, P < 0.001), and presence of chest wall edema and pleural effusions on chest radiograph (Mann-Whitney test, P = 0.003). Amount of red blood cells transfused and use of nitric oxide were independently associated with increased duration of mechanical ventilation (P = 0.012 and 0.014, respectively). Fluid overload is associated with prolonged duration of mechanical ventilation and PICU length of stay after congenital heart surgery. Fluid overload was also associated with physiological markers of respiratory restriction. A randomized controlled trial of a restrictive versus liberal fluid replacement strategy is necessary in this patient population, but in the meantime, accumulating observational evidence suggests that cautious use of fluid in the postoperative care may be warranted.

  6. Mechanical Ventilation during Extracorporeal Membrane Oxygenation in Patients with Acute Severe Respiratory Failure.

    PubMed

    Zhang, Zhongheng; Gu, Wan-Jie; Chen, Kun; Ni, Hongying

    2017-01-01

    Conventionally, a substantial number of patients with acute respiratory failure require mechanical ventilation (MV) to avert catastrophe of hypoxemia and hypercapnia. However, mechanical ventilation per se can cause lung injury, accelerating the disease progression. Extracorporeal membrane oxygenation (ECMO) provides an alternative to rescue patients with severe respiratory failure that conventional mechanical ventilation fails to maintain adequate gas exchange. The physiology behind ECMO and its interaction with MV were reviewed. Next, we discussed the timing of ECMO initiation based on the risks and benefits of ECMO. During the running of ECMO, the protective ventilation strategy can be employed without worrying about catastrophic hypoxemia and carbon dioxide retention. There is a large body of evidence showing that protective ventilation with low tidal volume, high positive end-expiratory pressure, and prone positioning can provide benefits on mortality outcome. More recently, there is an increasing popularity on the use of awake and spontaneous breathing for patients undergoing ECMO, which is thought to be beneficial in terms of rehabilitation.

  7. Mechanical Ventilation during Extracorporeal Membrane Oxygenation in Patients with Acute Severe Respiratory Failure

    PubMed Central

    Gu, Wan-Jie; Chen, Kun; Ni, Hongying

    2017-01-01

    Conventionally, a substantial number of patients with acute respiratory failure require mechanical ventilation (MV) to avert catastrophe of hypoxemia and hypercapnia. However, mechanical ventilation per se can cause lung injury, accelerating the disease progression. Extracorporeal membrane oxygenation (ECMO) provides an alternative to rescue patients with severe respiratory failure that conventional mechanical ventilation fails to maintain adequate gas exchange. The physiology behind ECMO and its interaction with MV were reviewed. Next, we discussed the timing of ECMO initiation based on the risks and benefits of ECMO. During the running of ECMO, the protective ventilation strategy can be employed without worrying about catastrophic hypoxemia and carbon dioxide retention. There is a large body of evidence showing that protective ventilation with low tidal volume, high positive end-expiratory pressure, and prone positioning can provide benefits on mortality outcome. More recently, there is an increasing popularity on the use of awake and spontaneous breathing for patients undergoing ECMO, which is thought to be beneficial in terms of rehabilitation. PMID:28127231

  8. [Using non-invasive mask lung ventilation in cardiosurgical patients with acute respiratory distress syndrome].

    PubMed

    Eremenko, A A; Levikov, D I; Egorov, V M; Zorin, D E; Kolomiets, V Ia

    2004-01-01

    Twenty patients aged 33 to 71 (54 +/- 6) years (male - 13, female - 7) operated on the heart and main vessels were included in the case study. I.e. those patient were investigated, whose immediate postoperative results were complicated by the syndrome of multiple organ failure (SMOF) that developed due to different-etiology shock, huge blood loss and hemotransfusion or to the syndrome of acute postperfusion lung damage. NIMLV was made at the resolution stage of SMOF and ARDS after artificial pulmonary ventilation (APL) for as long as 5-7 days. The indications for extubation of patients were as follows: PaO2/FiO2 of 200 and more mm Hg, respiratory rate (RR) of less than 30 per min, respiratory volume of more than 6 ml/kg with pressure support at inspiration of less than 5 cm H2O and with the total pressure at the exhalation end of no more than 3 cm H2O. Mask ventilation sessions were started in a growing dyspnea of more than 26 per min, a decreased content of oxyhemoglobin in arterial blood (below 95% at oxygen inhalation of 10-15 l/min), involvement of auxiliary muscles in breathing and at subjective complaints of patients related with complicated breathing and with being short of air. The mask SIMV ventilation with a preset apparatus-aided rate of inhales of 2-6/min, with Bi-PAP and PSV inhale pressure of 15 cm/ H2O and with PEEP of 3-5 cm/ H2O was made by 40-120 min sessions; the number of IFMLV sessions ranged from 6 to 22/patient, mean - 11 +/- 1.1 h. The total IFMLV duration was 10.7 +/- 1.1 h. The need for respiratory support persisted for 4-6 days after extubation. In 18 (90%) of 20 patients, the mask pulmonary ventilation resolved the respiratory insufficiency. Two (10%) patients were reintubated because of progressing multiorgan failure and because of obturation of the left main bronchus. A questioning of patients on the comfort degree of mask ventilation denoted the Flow-by triggering to be by far better tolerated by patients versus the pressure

  9. Rocking bed and prolonged independence from nocturnal non-invasive ventilation in neurogenic respiratory failure associated with limb weakness

    PubMed Central

    Cormican, L; Higgins, S; Davidson, A; Howard, R; Williams, A

    2004-01-01

    A 40 year old mother of three with autosomal dominant scapuloperoneal muscular dystrophy presented with severe neurogenic respiratory failure requiring nocturnal non-invasive ventilation (NIV). Because of the development of profound proximal muscular weakness as a consequence of the progressive nature of her neurological disease, she eventually was unable to apply and remove the facial interface to set up her NIV circuit. She therefore became dependent on her children and carers to start and stop NIV during the night. A rocking bed was successfully employed as an alternative to nocturnal NIV. Ventilation was facilitated by the passive movement of the diaphragm as a consequence of the movement of the abdominal contents under the effect of gravity. Benefit was demonstrated objectively by pulse oximetry and subjectively by the improvement in the patient's symptomatology and continued independence at night. The ease of use of a rocking bed should be borne in mind when the necessity for nocturnal ventilatory support in neuromuscular disease results in the potential loss of independence for a patient. PMID:15192173

  10. Validation of indirect calorimetry for measurement of energy expenditure in healthy volunteers undergoing pressure controlled non-invasive ventilation support.

    PubMed

    Siirala, Waltteri; Noponen, Tommi; Olkkola, Klaus T; Vuori, Arno; Koivisto, Mari; Hurme, Saija; Aantaa, Riku

    2012-02-01

    The aim of this validation study was to assess the reliability of gas exchange measurement with indirect calorimetry among subjects who undergo non-invasive ventilation (NIV). Oxygen consumption (VO2) and carbon dioxide production (VCO2) were measured in twelve healthy volunteers. Respiratory quotient (RQ) and resting energy expenditure (REE) were then calculated from the measured VO2 and VCO2 values. During the measurement period the subjects were breathing spontaneously and ventilated using NIV. Two different sampling air flow values 40 and 80 l/min were used. The gas leakage from the measurement setup was assessed with a separate capnograph. The mean weight of the subjects was 93 kg. Their mean body mass index was 29 (range 22-40) kg/m2. There was no statistically significant difference in the measured values for VO2, VCO2, RQ and REE during NIV-supported breathing and spontaneous breathing. The change of sampling air flow had no statistically significant effect on any of the above parameters. We found that REE can be accurately measured with an indirect calorimeter also during NIV-supported breathing and the change of sampling air flow does not distort the gas exchange measurement. A higher sampling air flow in indirect calorimetry decreases the possibility for air leakages in the measurement system and increases the reliability of REE measurement.

  11. A new horizon for the use of non-invasive ventilation in patients with acute respiratory distress syndrome

    PubMed Central

    2016-01-01

    Non-invasive ventilation (NIV) has assumed an important role in the management of acute respiratory failure (ARF). NIV, compared with standard medical therapy, improves survival and reduces complications in selected patients with ARF. NIV represents the first-line intervention for some forms of ARF, such as chronic obstructive pulmonary disease (COPD) exacerbations and acute cardiogenic pulmonary edema. The use of NIV is also well supported for immunocompromised patients who are at high risk for infectious complications from endotracheal intubation. Selection of appropriate patients is crucial for optimizing NIV success rates. Appropriate ventilator settings, a well-fitting and comfortable interface, and a team skilled and experienced in managing NIV are key components to its success. In a recent issue of the Journal of the American Medical Association, Patel et al. reported the results of their single-center trial of 83 patients with acute respiratory distress syndrome (ARDS) who were randomly assigned to NIV delivered via a helmet or face mask. Patients assigned to the helmet group exhibited a significantly lower intubation rate and were more likely to survive through 90 days. This perspective reviews the findings of this trial in the context of current clinical practice and in light of data from the literature focused on the potential reasons for success of NIV delivered through a helmet compared to face mask. The implications for early management of patients with ARDS are likewise discussed. PMID:27761452

  12. A comparison of changes in cardiac preload variables during graded hypovolemia and hypervolemia in mechanically ventilated dogs.

    PubMed

    Fujita, Yoshihisa; Yamamoto, Tokunori; Sano, Itsuro; Yoshioka, Naoki; Hinenoya, Hajime

    2004-12-01

    We developed an online monitoring system to measure systolic blood pressure variation (SPV) and its down (dDown) and up components, along with pulse pressure variation (dPP). Using the system, we compared different cardiac preload indicators-such as stroke volume variation (SVV) and corrected flow time (FTc)-along with central venous pressure and pulmonary artery occlusion pressure in mechanically-ventilated dogs during normovolemia, graded hypovolemia (-200 and -350 mL), and hypervolemia (+200 and +350 mL). We simultaneously measured these preload indicators along with global hemodynamic variables and investigated their validity and limitations to access preload changes. SPV increased from 4.8 +/- 1.4 mm Hg at baseline to 11.2 +/- 1.8 mm Hg during hypovolemia (-350 mL), but it did not change significantly during hypervolemia. Similar changes were observed with dDown, dPP, and SVV. FTc, conversely, increased during hypervolemia but remained unchanged during hypovolemia. The results of this study indicate that SPV, dDown, dPP, and SVV are useful indicators of hypovolemia, but not of hypervolemia. Conversely, hypovolemia could not be detected reliably by FTc, but it does reflect blood volume changes during hypervolemia. Although SPV, dDown, and dPP measurements require no additional invasion and cost beyond arterial cannulation, their limits must be kept in mind for the monitoring of blood volume status in mechanically-ventilated patients.

  13. A Survey of Mechanical Ventilator Practices Across Burn Centers in North America

    PubMed Central

    Rhie, Ryan Y.; Lundy, Jonathan B.; Cartotto, Robert; Henderson, Elizabeth; Pressman, Melissa A.; Joe, Victor C.; Aden, James K.; Driscoll, Ian R.; Faucher, Lee D.; McDermid, Robert C.; Mlcak, Ronald P.; Hickerson, William L.; Jeng, James C.

    2016-01-01

    Burn injury introduces unique clinical challenges that make it difficult to extrapolate mechanical ventilator (MV) practices designed for the management of general critical care patients to the burn population. We hypothesize that no consensus exists among North American burn centers with regard to optimal ventilator practices. The purpose of this study is to examine various MV practice patterns in the burn population and to identify potential opportunities for future research. A researcher designed, 24-item survey was sent electronically to 129 burn centers. The χ2, Fisher’s exact, and Cochran–Mantel–Haenszel tests were used to determine if there were significant differences in practice patterns. We analyzed 46 questionnaires for a 36% response rate. More than 95% of the burn centers reported greater than 100 annual admissions. Pressure support and volume assist control were the most common initial MV modes used with or without inhalation injury. In the setting of Berlin defined mild acute respiratory distress syndrome (ARDS), ARDSNet protocol and optimal positive end-expiratory pressure were the top ventilator choices, along with fluid restriction/diuresis as a nonventilator adjunct. For severe ARDS, airway pressure release ventilation and neuromuscular blockade were the most popular. The most frequently reported time frame for mechanical ventilation before tracheostomy was 2 weeks (25 of 45, 55%); however, all respondents reported in the affirmative that there are certain clinical situations where early tracheostomy is warranted. Wide variations in clinical practice exist among North American burn centers. No single ventilator mode or adjunct prevails in the management of burn patients regardless of pulmonary insult. Movement toward American Burn Association–supported, multicenter studies to determine best practices and guidelines for ventilator management in burn patients is prudent in light of these findings. PMID:26135527

  14. Linking Ventilation Heterogeneity Quantified via Hyperpolarized 3He MRI to Dynamic Lung Mechanics and Airway Hyperresponsiveness.

    PubMed

    Lui, Justin K; Parameswaran, Harikrishnan; Albert, Mitchell S; Lutchen, Kenneth R

    2015-01-01

    Advancements in hyperpolarized helium-3 MRI (HP 3He-MRI) have introduced the ability to render and quantify ventilation patterns throughout the anatomic regions of the lung. The goal of this study was to establish how ventilation heterogeneity relates to the dynamic changes in mechanical lung function and airway hyperresponsiveness in asthmatic subjects. In four healthy and nine mild-to-moderate asthmatic subjects, we measured dynamic lung resistance and lung elastance from 0.1 to 8 Hz via a broadband ventilation waveform technique. We quantified ventilation heterogeneity using a recently developed coefficient of variation method from HP 3He-MRI imaging. Dynamic lung mechanics and imaging were performed at baseline, post-challenge, and after a series of five deep inspirations. AHR was measured via the concentration of agonist that elicits a 20% decrease in the subject's forced expiratory volume in one second compared to baseline (PC20) dose. The ventilation coefficient of variation was correlated to low-frequency lung resistance (R = 0.647, P < 0.0001), the difference between high and low frequency lung resistance (R = 0.668, P < 0.0001), and low-frequency lung elastance (R = 0.547, P = 0.0003). In asthmatic subjects with PC20 values <25 mg/mL, the coefficient of variation at baseline exhibited a strong negative trend (R = -0.798, P = 0.02) to PC20 dose. Our findings were consistent with the notion of peripheral rather than central involvement of ventilation heterogeneity. Also, the degree of AHR appears to be dependent on the degree to which baseline airway constriction creates baseline ventilation heterogeneity. HP 3He-MRI imaging may be a powerful predictor of the degree of AHR and in tracking the efficacy of therapy.

  15. Home Mechanical Ventilation in Childhood-Onset Hereditary Neuromuscular Diseases: 13 Years’ Experience at a Single Center in Korea

    PubMed Central

    Han, Young Joo; Park, June Dong; Lee, Bongjin; Choi, Yu Hyeon; Suh, Dong In; Lim, Byung Chan; Chae, Jong-Hee

    2015-01-01

    Introduction Children with hereditary neuromuscular diseases (NMDs) are at a high risk of morbidity and mortality related to respiratory failure. The use of home mechanical ventilation (HMV) has saved the lives of many children with NMD but, due to a lack of studies, dependable guidelines are not available. We drew upon our experience to compare the various underlying NMDs and to evaluate HMV with regard to respiratory morbidity, the proper indications and timing for its use, and to develop a policy to improve the quality of home noninvasive ventilation (NIV). Methods We retrospectively analyzed the medical records of 57 children with childhood-onset hereditary NMDs in whom HMV was initiated between January 2000 and May 2013 at Seoul National University Children's Hospital. The degree of respiratory morbidity was estimated by the frequency and duration of hospitalizations caused by respiratory distress. Results The most common NMD was spinal muscular atrophy (SMA, n = 33). Emergent mechanical ventilation was initiated in 44% of the patients before the confirmed diagnosis, and the indicators of pre-HMV respiratory morbidity (e.g., extubation trials, hypoxia, hospitalizations, and intensive care unit stay) were greater in these patients than in others. The proportion of post-HMV hospitalizations (range, 0.00−0.52; median, 0.01) was lower than that of pre-HMV hospitalizations (0.02−1.00; 0.99) (P < 0.001). Eight patients were able to maintain home NIV. The main causes of NIV failure were air leakage and a large amount of airway secretions. Conclusions The application of HMV helped reduce respiratory morbidity in children with childhood-onset hereditary NMD. Patients with SMA type I can benefit from an early diagnosis and the timely application of HMV. The choice between invasive and noninvasive HMV should be based on the patient’s age and NIV trial tolerance. Systematic follow-up guidelines provided by a multidisciplinary team are needed. PMID:25822836

  16. Indicators of fatigue and of prolonged weaning from mechanical ventilation in surgical patients.

    PubMed

    O'Keefe, G E; Hawkins, K; Boynton, J; Burns, D

    2001-01-01

    Indicators of weaning success have been tested primarily in patients who have been ventilated for short periods of time, and they may not be as accurate in cases where support has been required for longer than a few days. In patients requiring longer periods of support it is difficult to estimate the likelihood of successful liberation. Therefore we evaluated established weaning indices for their accuracy in surgical patients who required > or = 72 hours of mechanical ventilation. Surgical patients who required mechanical ventilation for > or = 72 hours were prospectively followed (over 6 months). We obtained standard indices of ventilatory function daily once patients were ready to wean. These indices included the respiratory rate/tidal volume ratio (RSBI), the maximal inspiratory pressure, and the minute ventilation. The duration of weaning and explicitly defined episodes of fatigue were the outcomes of interest. Statistical analyses evaluated the multiple factors that might influence the duration of weaning. Ninety-five patients (66% trauma; 34% surgery) survived to begin weaning, and 93% were liberated. The median duration of mechanical ventilation prior to weaning was 4 days (range 3-16 days), and the median duration of weaning was 3 days (range 0-56 days). Fatigue occurred in 36 patients and was not reliably predicted by any of the weaning measurements. However, a RSBI of > 105 on the first day of weaning was associated with prolonged weaning. By multivariate analysis, an RSBI of > 105 on the first day of weaning predicted prolonged weaning (hazard ratio 1.9; p = 0.03). After 72 hours of mechanical ventilation, clinical fatigue and successful liberation are not reliably predicted by standard indices of respiratory muscle strength and reserve. However, an RSBI of >105 observed once the patient is ready to wean is associated with prolonged weaning.

  17. Assessment of the effect of continuous sedation with mechanical ventilation on adrenal insufficiency in patients with traumatic brain injury.

    PubMed

    Li, Min; Zhang, Ying; Wu, Kang-Song; Hu, Ying-Hong

    2016-03-01

    The aim of this study was to assess the effect of continuous propofol sedation plus prolonged mechanical ventilation on adrenal insufficiency (AI) in patients with traumatic brain injury (TBI). Eighty-five adult patients diagnosed with moderate TBI (Glasgow Coma Scale (GCS) score 9-13) from October 2011 to October 2012 were included in this prospective study. The patients comprised three groups: no mechanical ventilation and sedation (n=27), mechanical ventilation alone (n=24) and mechanical ventilation plus sedation (n=34). The low-dose short Synacthen test was performed at 8:00 on the first, third, and fifth days after TBI. Logistic regression analysis was performed to identify factors affecting the use of mechanical ventilation and sedation, and the incidence of AI. On the fifth day after injury, the mean baseline cortisol and simulated cortisol levels were significantly lower in the mechanical ventilation plus sedation group compared with the other two groups. Multivariate regression analysis showed that the Acute Physiology and Chronic Health Evaluation (APACHE) score was independently associated with treatment with mechanical ventilation and sedation compared to mechanical ventilation alone. Furthermore, hypoxemia on admission and shock were associated with the development of AI. The findings showed that sedation is associated with an increased incidence of AI. Patients with TBI who are treated with continuous sedation should be monitored for AI carefully.

  18. Nonlinear mechanisms determining expiratory flow limitation in mechanical ventilation: a model-based interpretation.

    PubMed

    Barbini, Paolo; Cevenini, Gabriele; Avanzolni, Guido

    2003-09-01

    A nonlinear model of breathing mechanics, in which the tracheobronchial airways are considered in three serial segments, is presented to obtain insights into the mechanisms underlying expiratory flow limitation (EFL) in mechanically ventilated patients. Chronic obstructive pulmonary disease (COPD) and normal conditions were simulated and EFL was detected by application of negative expiratory pressure at the mouth or resistance reduction of the expiratory circuit. Simulation results confirm that both techniques reveal remarkable differences in the flow-volume curves between normal subjects and COPD patients, the former showing absence of EFL and the latter exhibiting EFL over most of the expiration. To interpret the role of different nonlinear mechanisms in producing EFL, different flow-volume curves obtained by changing model parameter values were analyzed. An increase in lower-airway resistance did not give rise to EFL, whereas a change in the pressure-volume characteristic of the intermediate-airway segment, towards increased resistance and easier collapse, significantly modified system behavior. In particular, EFL was observed when this intermediate-segment change was combined with an increase in lower-airway resistance. This evidence suggests that modifications, producing loss of radial traction and consequent narrowing of the airways in the peribronchial region, may play a leading role in EFL in COPD patients.

  19. Effect of regional lung inflation on ventilation heterogeneity at different length scales during mechanical ventilation of normal sheep lungs.

    PubMed

    Wellman, Tyler J; Winkler, Tilo; Costa, Eduardo L V; Musch, Guido; Harris, R Scott; Venegas, Jose G; Vidal Melo, Marcos F

    2012-09-01

    Heterogeneous, small-airway diameters and alveolar derecruitment in poorly aerated regions of normal lungs could produce ventilation heterogeneity at those anatomic levels. We modeled the washout kinetics of (13)NN with positron emission tomography to examine how specific ventilation (sV) heterogeneity at different length scales is influenced by lung aeration. Three groups of anesthetized, supine sheep were studied: high tidal volume (Vt; 18.4 ± 4.2 ml/kg) and zero end-expiratory pressure (ZEEP) (n = 6); low Vt (9.2 ± 1.0 ml/kg) and ZEEP (n = 6); and low Vt (8.2 ± 0.2 ml/kg) and positive end-expiratory pressure (PEEP; 19 ± 1 cmH(2)O) (n = 4). We quantified fractional gas content with transmission scans, and sV with emission scans of infused (13)NN-saline. Voxel (13)NN-washout curves were fit with one- or two-compartment models to estimate sV. Total heterogeneity, measured as SD[log(10)(sV)], was divided into length-scale ranges by measuring changes in variance of log(10)(sV), resulting from progressive filtering of sV images. High-Vt ZEEP showed higher sV heterogeneity at <12- (P < 0.01), 12- to 36- (P < 0.01), and 36- to 60-mm (P < 0.05) length scales compared with low-Vt PEEP, with low-Vt ZEEP in between. Increased heterogeneity was associated with the emergence of low sV units in poorly aerated regions, with a high correlation (r = 0.95, P < 0.001) between total heterogeneity and the fraction of lung with slow washout. Regional mean fractional gas content was inversely correlated with regional sV heterogeneity at <12- (r = -0.67), 12- to 36- (r = -0.74), and >36-mm (r = -0.72) length scales (P < 0.001). We conclude that sV heterogeneity at length scales <60 mm increases in poorly aerated regions of mechanically ventilated normal lungs, likely due to heterogeneous small-airway narrowing and alveolar derecruitment. PEEP reduces sV heterogeneity by maintaining lung expansion and airway patency at those small length scales.

  20. Prospective observational cohort study of patients with weaning failure admitted to a specialist weaning, rehabilitation and home mechanical ventilation centre

    PubMed Central

    Mifsud Bonnici, Denise; Sanctuary, Thomas; Murphy, Patrick B; Steier, Joerg; Marino, Philip; Pattani, Hina; Creagh-Brown, Ben C; Hart, Nicholas

    2016-01-01

    Objectives According to National Health Service England (NHSE) specialist respiratory commissioning specification for complex home ventilation, patients with weaning failure should be referred to a specialist centre. However, there are limited data reporting the clinical outcomes from such centres. Setting Prospective observational cohort study of patients admitted to a UK specialist weaning, rehabilitation and home mechanical ventilation centre between February 2005 and July 2013. Participants 262 patients admitted with a median age of 64.2 years (IQR 52.6–73.2 years). 59.9% were male. Results 39.7% of patients had neuromuscular and/or chest wall disease, 21% were postsurgical, 19.5% had chronic obstructive pulmonary disease (COPD), 5.3% had obesity-related respiratory failure and 14.5% had other diagnoses. 64.1% of patients were successfully weaned, with 38.2% weaned fully from ventilation, 24% weaned to nocturnal non-invasive ventilation (NIV), 1.9% weaned to nocturnal NIV with intermittent NIV during the daytime. 21.4% of patients were discharged on long-term tracheostomy ventilation. The obesity-related respiratory failure group were most likely to wean (relative risk (RR) for weaning success=1.48, 95% CI 1.35 to 1.77; p<0.001), but otherwise weaning success rates did not significantly vary by diagnostic group. The median time-to-wean was 19 days (IQR 9–33) and the median duration of stay was 31 days (IQR 16–50), with no difference observed between the groups. Weaning centre mortality was 14.5%, highest in the COPD group (RR=2.15, 95% CI 1.19 to 3.91, p=0.012) and lowest in the neuromuscular and/or chest wall disease group (RR=0.34, 95% CI 0.16 to 0.75, p=0.007). Of all patients discharged alive, survival was 71.7% at 6 months and 61.8% at 12 months postdischarge. Conclusions Following NHSE guidance, patients with weaning delay and failure should be considered for transfer to a specialist centre where available, which can demonstrate

  1. Monitoring of total positive end-expiratory pressure during mechanical ventilation by artificial neural networks.

    PubMed

    Perchiazzi, Gaetano; Rylander, Christian; Pellegrini, Mariangela; Larsson, Anders; Hedenstierna, Göran

    2016-04-11

    Ventilation treatment of acute lung injury (ALI) requires the application of positive airway pressure at the end of expiration (PEEPapp) to avoid lung collapse. However, the total pressure exerted on the alveolar walls (PEEPtot) is the sum of PEEPapp and intrinsic PEEP (PEEPi), a hidden component. To measure PEEPtot, ventilation must be discontinued with an end-expiratory hold maneuver (EEHM). We hypothesized that artificial neural networks (ANN) could estimate the PEEPtot from flow and pressure tracings during ongoing mechanical ventilation. Ten pigs were mechanically ventilated, and the time constant of their respiratory system (τRS) was measured. We shortened their expiratory time (TE) according to multiples of τRS, obtaining different respiratory patterns (Rpat). Pressure (PAW) and flow (V'AW) at the airway opening during ongoing mechanical ventilation were simultaneously recorded, with and without the addition of external resistance. The last breath of each Rpat included an EEHM, which was used to compute the reference PEEPtot. The entire protocol was repeated after the induction of ALI with i.v. injection of oleic acid, and 382 tracings were obtained. The ANN had to extract the PEEPtot, from the tracings without an EEHM. ANN agreement with reference PEEPtot was assessed with the Bland-Altman method. Bland Altman analysis of estimation error by ANN showed -0.40 ± 2.84 (expressed as bias ± precision) and ±5.58 as limits of agreement (data expressed as cmH2O). The ANNs estimated the PEEPtot well at different levels of PEEPapp under dynamic conditions, opening up new possibilities in monitoring PEEPi in critically ill patients who require ventilator treatment.

  2. Neurally adjusted ventilation assist in weaning difficulty: First case report from India

    PubMed Central

    Baldi, Milind; Sehgal, Inderpaul Singh; Dhooria, Sahajal; Behera, Digambar; Agarwal, Ritesh

    2016-01-01

    Invasive mechanical ventilation is an integral component in the management of critically ill patients. In certain situations, liberation from mechanical ventilation becomes difficult resulting in prolonged ventilation. Patient-ventilator dyssynchrony is a frequently encountered reason for difficult weaning. Neurally adjusted ventilatory assist (NAVA) is a novel mode of ventilation that utilizes the electrical activity of diaphragm to pick up respiratory signals and delivers assistance in proportion to the ventilatory requirement of a patient. It may, therefore, be associated with a better patient-ventilator synchrony thereby facilitating weaning. Herein, we report the first case from India describing the use of NAVA in successfully weaning a patient with difficult weaning. PMID:27390463

  3. Mechanical ventilation alone, and in the presence sepsis, induces peripheral skeletal muscle catabolism in neonatal pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reduced rates of skeletal muscle accretion are a prominent feature of the metabolic response to sepsis in infants and children. Septic neonates often require medical support with mechanical ventilation (MV). The combined effects of MV and sepsis in muscle have not been examined in neonates, in whom ...

  4. Mechanical ventilation and sepsis induce skeletal muscle catabolism in neonatal pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reduced rates of skeletal muscle accretion are a prominent feature of the metabolic response to sepsis in infants and children. Septic neonates often require medical support with mechanical ventilation (MV). The combined effects of MV and sepsis in muscle have not been examined in neonates, in whom ...

  5. Clinical study on VATS combined mechanical ventilation treatment of ARDS secondary to severe chest trauma

    PubMed Central

    Qi, Yongjun

    2016-01-01

    The aim of the study was to investigate the clinical effects of microinvasive video-assisted thoracoscopic surgery (VATS) combined with mechanical ventilation in the treatment of acute respiratory distress syndrome (ARDS) secondary to severe chest trauma. A total of 62 patients with ARDS secondary to severe chest trauma were divided into the observation and control groups. The patients in the observation groups were treated with VATS combined with early mechanical ventilation while patients in the control group were treated using routine open thoracotomy combined with early mechanical ventilation. Compared to the controls, the survival rate of the observation group was significantly higher. The average operation time of the observation group was significantly shorter than that of the control group, and the incidence of complications in the perioperative period of the observation group was significantly lower than that of the control group (p<0.05). The average application time of the observation group was significantly shorter than that of the control group, and the incidence of ventilator-associated complications was significantly lower than that of the control group (p<0.05). In conclusion, a reasonable understanding of the indications and contraindications of VATS, combined with early mechanical treatment significantly improved the success rate of the treatment of ARDS patients secondary to severe chest trauma and reduced the complications. PMID:27446317

  6. Mechanical Ventilation in Hypobaric Atmosphere - Aeromedical Transport of Critically Ill Patients

    DTIC Science & Technology

    2004-09-01

    Specialist Centro de Instrucción de Medicina Aeroespacial (CIMA) Arturo Soria 82 28027 Madrid SPAIN LtCol. Dr. Ríos Tejada F. Aviation and Space...Medicine Specialist Centro de Instrucción de Medicina Aeroespacial (CIMA) Arturo Soria 82 28027 Madrid SPAIN INTRODUCTION Mechanical ventilation is

  7. A Critical Review of Mechanical Ventilation Virtual Simulators: Is It Time to Use Them?

    PubMed Central

    Gomes, Gabriela Carvalho; Sousa, Nancy Delma Silva Vega Canjura; Carvalho, Andrea K; Diniz, Marcelo Emanoel Bezerra; Viana Junior, Antonio Brazil; Holanda, Marcelo Alcantara

    2016-01-01

    Background Teaching mechanical ventilation at the bedside with real patients is difficult with many logistic limitations. Mechanical ventilators virtual simulators (MVVS) may have the potential to facilitate mechanical ventilation (MV) training by allowing Web-based virtual simulation. Objective We aimed to identify and describe the current available MVVS, to compare the usability of their interfaces as a teaching tool and to review the literature on validation studies. Methods We performed a comparative evaluation of the MVVS, based on a literature/Web review followed by usability tests according to heuristic principles evaluation of their interfaces as performed by professional experts on MV. Results Eight MVVS were identified. They showed marked heterogeneity, mainly regarding virtual patient's anthropomorphic parameters, pulmonary gas exchange, respiratory mechanics and muscle effort configurations, ventilator terminology, basic ventilatory modes, settings alarms, monitoring parameters, and design. The Hamilton G5 and the Xlung covered a broader number of parameters, tools, and have easier Web-based access. Except for the Xlung, none of the simulators displayed monitoring of arterial blood gases and alternatives to load and save the simulation. The Xlung obtained the greater scores on heuristic principles assessments and the greater score of easiness of use, being the preferred MVVS for teaching purposes. No strong scientific evidence on the use and validation of the current MVVS was found. Conclusions There are only a few MVVS currently available. Among them, the Xlung showed a better usability interface. Validation tests and development of new or improvement of the current MVVS are needed. PMID:27731850

  8. Swallowing rehabilitation of dysphagic tracheostomized patients under mechanical ventilation in intensive care units: a feasibility study

    PubMed Central

    Rodrigues, Katia Alonso; Machado, Flávia Ribeiro; Chiari, Brasília Maria; Rosseti, Heloísa Baccaro; Lorenzon, Paula; Gonçalves, Maria Inês Rebelo

    2015-01-01

    Objective The aim of the present study was to assess the feasibility of the early implementation of a swallowing rehabilitation program in tracheostomized patients under mechanical ventilation with dysphagia. Methods This prospective study was conducted in the intensive care units of a university hospital. We included hemodynamically stable patients under mechanical ventilation for at least 48 hours following 48 hours of tracheostomy and with an appropriate level of consciousness. The exclusion criteria were previous surgery in the oral cavity, pharynx, larynx and/or esophagus, the presence of degenerative diseases or a past history of oropharyngeal dysphagia. All patients were submitted to a swallowing rehabilitation program. An oropharyngeal structural score, a swallowing functional score and an otorhinolaryngological structural and functional score were determined before and after swallowing therapy. Results We included 14 patients. The mean duration of the rehabilitation program was 12.4 ± 9.4 days, with 5.0 ± 5.2 days under mechanical ventilation. Eleven patients could receive oral feeding while still in the intensive care unit after 4 (2 - 13) days of therapy. All scores significantly improved after therapy. Conclusion In this small group of patients, we demonstrated that the early implementation of a swallowing rehabilitation program is feasible even in patients under mechanical ventilation. PMID:25909315

  9. The Effects of Guided Imagery on Patients Being Weaned from Mechanical Ventilation

    PubMed Central

    Spiva, LeeAnna; Hart, Patricia L.; Gallagher, Erin; McVay, Frank; Garcia, Melida; Malley, Karen; Kadner, Marsha; Segars, Angela; Brakovich, Betsy; Horton, Sonja Y.; Smith, Novlette

    2015-01-01

    The study purpose was to assess the effects of guided imagery on sedation levels, sedative and analgesic volume consumption, and physiological responses of patients being weaned from mechanical ventilation. Forty-two patients were selected from two community acute care hospitals. One hospital served as the comparison group and provided routine care (no intervention) while the other hospital provided the guided imagery intervention. The intervention included two sessions, each lasting 60 minutes, offered during morning weaning trials from mechanical ventilation. Measurements were recorded in groups at baseline and 30- and 60-minute intervals and included vital signs and Richmond Agitation-Sedation Scale (RASS) score. Sedative and analgesic medication volume consumption were recorded 24 hours prior to and after the intervention. The guided imagery group had significantly improved RASS scores and reduced sedative and analgesic volume consumption. During the second session, oxygen saturation levels significantly improved compared to the comparison group. Guided imagery group had 4.88 less days requiring mechanical ventilation and 1.4 reduction in hospital length of stay compared to the comparison group. Guided imagery may be complementary and alternative medicine (CAM) intervention to provide during mechanical ventilation weaning trials. PMID:26640501

  10. Mechanical ventilation induces myokine expression and catabolism in peripheral skeletal muscle in pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Endotoxin (LPS)-induced sepsis increases circulating cytokines which have been associated with skeletal muscle catabolism. During critical illness, it has been postulated that muscle wasting associated with mechanical ventilation (MV) occurs due to inactivity. We hypothesize that MV and sepsis promo...

  11. Automated logging of inspiratory and expiratory non-synchronized breathing (ALIEN) for mechanical ventilation.

    PubMed

    Chiew, Yeong Shiong; Pretty, Christopher G; Beatson, Alex; Glassenbury, Daniel; Major, Vincent; Corbett, Simon; Redmond, Daniel; Szlavecz, Akos; Shaw, Geoffrey M; Chase, J Geoffrey

    2015-01-01

    Asynchronous Events (AEs) during mechanical ventilation (MV) result in increased work of breathing and potential poor patient outcomes. Thus, it is important to automate AE detection. In this study, an AE detection method, Automated Logging of Inspiratory and Expiratory Non-synchronized breathing (ALIEN) was developed and compared between standard manual detection in 11 MV patients. A total of 5701 breaths were analyzed (median [IQR]: 500 [469-573] per patient). The Asynchrony Index (AI) was 51% [28-78]%. The AE detection yielded sensitivity of 90.3% and specificity of 88.3%. Automated AE detection methods can potentially provide clinicians with real-time information on patient-ventilator interaction.

  12. Noninvasive Mechanical Ventilation in Helicopter Emergency Medical Services Saves Time and Oxygen and Improves Patient and Mission Safety: A Pilot Study.

    PubMed

    Garrote, Jose Ignacio; Aylagas, Diego; Gutierrez, Jose M; Sinisterra, Juan A; Gowran, Brian Mc; Medina, Alberto; Díaz-Tendero, Javier; Gómez-Calcerrada, Pablo; Crespo, Ricardo

    2015-01-01

    Noninvasive mechanical ventilation (NIMV) is used increasingly in patients with severe respiratory distress and has clear benefits over standard medical therapy (SMT) in terms of patient safety. NIMV is particularly useful in cardiogenic acute pulmonary edema and in exacerbations of chronic obstructive pulmonary disease, both of which are frequent reasons for an emergency medical services dispatch. Early use of NIMV avoids complications in these patients in many cases. To date, the use of noninvasive positive-pressure ventilation in the air medical environment has been minimally researched. We evaluated NIMV versus SMT in the helicopter emergency medical services environment in patients with cardiogenic acute pulmonary edema and exacerbated chronic obstructive pulmonary disease. The parameters assessed were stabilization time, tolerance, safety, clinical response, and oxygen consumption. Bilevel noninvasive positive-pressure ventilation was the ventilatory mode used for all patients. The technique of NIMV in medical air transport is useful, easy to operate, and safe. It offers increased patient safety, reducing the need for invasive mechanical ventilation and its complications; better intervention times (35.8 minutes [NIMV] vs. 57.65 minutes [SMT], P < .05); improvement in aircraft operability; and a reduction in oxygen consumption (6.2 L/min vs. 9.8 L/min, P < .05), contributing to mission operability and safety.

  13. Differential Medical Aerosol Device and Interface Selection in Patients during Spontaneous, Conventional Mechanical and Noninvasive Ventilation.

    PubMed

    Ari, Arzu; Fink, James B

    2016-04-01

    Many aerosol delivery devices are available on the market that have different features, characteristics, and operating requirements that need to be considered for the effective treatment of patients with pulmonary diseases. Device selection in aerosol medicine is largely patient dependent. Since there is no aerosol device that suits all patient populations, device selection and successful integration of the prescribed aerosol device to patients is essential. This article explores key issues in differential device selection in spontaneously breathing adults with or without artificial airways, as well as critically ill patients receiving invasive and noninvasive ventilation, with discussion of considerations for integration of aerosol devices to each of these patient populations.

  14. Dynamic Characteristics of Mechanical Ventilation System of Double Lungs with Bi-Level Positive Airway Pressure Model

    PubMed Central

    Shen, Dongkai; Zhang, Qian

    2016-01-01

    In recent studies on the dynamic characteristics of ventilation system, it was considered that human had only one lung, and the coupling effect of double lungs on the air flow can not be illustrated, which has been in regard to be vital to life support of patients. In this article, to illustrate coupling effect of double lungs on flow dynamics of mechanical ventilation system, a mathematical model of a mechanical ventilation system, which consists of double lungs and a bi-level positive airway pressure (BIPAP) controlled ventilator, was proposed. To verify the mathematical model, a prototype of BIPAP system with a double-lung simulators and a BIPAP ventilator was set up for experimental study. Lastly, the study on the influences of key parameters of BIPAP system on dynamic characteristics was carried out. The study can be referred to in the development of research on BIPAP ventilation treatment and real respiratory diagnostics. PMID:27660646

  15. [Evaluation of a new nitric oxide delivery system during mechanical ventilation].

    PubMed

    Noguchi, T; Miyakawa, H; Mori, M; Kitano, T; Iwasaka, H; Oda, S; Taniguchi, K; Honda, N

    1994-07-01

    A new nitric oxide delivery and continuous monitoring system is described. During mechanical ventilation, this new system connected with Siemens Servo 900C ventilator was shown to be able to provide a constant inspired NO concentration (10-100 ppm) using chemiluminescence technique for NO analysis. Gas was analysed at the mixing chamber in front of the ventilator inlet and inspiratory tube connected with the soda-lime carbon-dioxide absorber. Both NO concentrations showed a good correlation (r = 0.99). The actual NO concentration from the NO supply cylinder was 1154 ppm and NO2 concentration was 14 ppm. In mongrel dogs, after 20 minutes of NO inhalation (10-100 ppm), the blood methemoglobin level reached a peak value of 2.2% starting from the pre-inhalation level of 0%. To optimize the safety of the clinical application of NO, its concentration should be measured continuously with chemiluminescence technique.

  16. Zinc Supplementation in Adult Mechanically Ventilated Trauma Patients is Associated with Decreased Occurrence of Ventilator-associated Pneumonia: A Secondary Analysis of a Prospective, Observational Study

    PubMed Central

    Hasanzadeh Kiabi, Farshad; Alipour, Abbas; Darvishi-Khezri, Hadi; Aliasgharian, Aily; Emami Zeydi, Amir

    2017-01-01

    Background: Ventilator-associated pneumonia (VAP) is a type of lung infection that typically affects critically ill patients undergoing mechanical ventilation (MV) in the Intensive Care Unit (ICU). The aim of this analysis is to determine potential association between zinc supplementation with the occurrence of VAP in adult mechanically ventilated trauma patients. Subjects and Methods: This secondary analysis of a prospective observational study was carried out over a period of 1 year in ICUs of one teaching hospital in Iran. A total of 186 adults mechanically ventilated trauma patients, who required at least 48 h of MV and received zinc sulfate supplement (n = 82) or not (n = 104) during their ICU stay, were monitored for the occurrence of VAP until their discharge from the ICU or death. Results: Forty-one of 186 patients developed VAP, 29.09 days after admission (95% confidence interval [CI]: 26.27–31.9). The overall incidence of VAP was 18.82 cases per 1000 days of intubation (95% CI: 13.86–25.57). Patients who received zinc sulfate supplement have smaller hazard of progression to VAP than others (hazard ratio: 0.318 [95% CI: 0.138–0.732]; P < 0.0001). Conclusion: The findings show that zinc supplementation may be associated with a significant reduction in the occurrence of VAP in adult mechanically ventilated trauma patients. Further well-designed randomized clinical trials to confirm the efficacy of this potential preventive modality are warranted. PMID:28197049

  17. Influence of different degrees of head elevation on respiratory mechanics in mechanically ventilated patients

    PubMed Central

    Martinez, Bruno Prata; Marques, Thaís Improta; Santos, Daniel Reis; Salgado, Vanessa Silva; Nepomuceno Júnior, Balbino Rivail; Alves, Giovani Assunção de Azevedo; Gomes Neto, Mansueto; Forgiarini Junior, Luiz Alberto

    2015-01-01

    Objective The positioning of a patient in bed may directly affect their respiratory mechanics. The objective of this study was to evaluate the respiratory mechanics of mechanically ventilated patients positioned with different head angles hospitalized in an intensive care unit. Methods This was a prospective physiological study in which static and dynamic compliance, resistive airway pressure, and peripheral oxygen saturation were measured with the head at four different positions (0° = P1, 30° = P2, 45° = P3, and 60° = P4). Repeated-measures analysis of variance (ANOVA) with a Bonferroni post-test and Friedman analysis were used to compare the values obtained at the different positions. Results A comparison of the 35 evaluated patients revealed that the resistive airway pressure values in the 0° position were higher than those obtained when patients were positioned at greater angles. The elastic pressure analysis revealed that the 60° position produced the highest value relative to the other positions. Regarding static compliance, a reduction in values was observed from the 0° position to the 60° position. The dynamic compliance analysis revealed that the 30° angle produced the greatest value compared to the other positions. The peripheral oxygen saturation showed little variation, with the highest value obtained at the 0° position. Conclusion The highest dynamic compliance value was observed at the 30° position, and the highest oxygenation value was observed at the 0° position. PMID:26761472

  18. Comparison of jet and ultrasonic nebulizer pulmonary aerosol deposition during mechanical ventilation.

    PubMed

    Harvey, C J; O'Doherty, M J; Page, C J; Thomas, S H; Nunan, T O; Treacher, D F

    1997-04-01

    Increased delivery of aerosol to a model lung (attached to a mechanical ventilator) has been demonstrated with an ultrasonic nebulizer as compared to a jet nebulizer. This study examined whether the increased aerosol deposition with an ultrasonic nebulizer could also be demonstrated in vivo. Seven patients (6 male and 1 female) were studied during mechanical ventilalion (Siemens Servo 900C, Middlesex, UK) after open heart surgery. Two studies were performed in each patient. In the first study, aerosol was delivered via a Siemens Servo 945 nebulizer system (high setting) driving a System 22 Acorn jet nebulizer (Medic-Aid, Sussex, UK) containing 3 mL (99m)technetium-labelled human serum albumin (99mTc-HSA) (50 microg; activity 74 MBq). In the second study, a DP100 ultrasonic nebulizer (DP Medical, Meylan, France) containing 12 mL 99mTc-HSA (50 microg; activity 185 MBq) was used. Pulmonary deposition was quantified using a gamma camera. The humidification of the circuit and the ventilator settings were kept constant according to the patient's clinical requirements. The total lung aerosol deposition (mean+/-SD), as a percentage of initial nebulizer activity, was greater using the ultrasonic nebulizer than using the jet nebulizer (53+/-1.4 vs 2.3+/-0.9%; p<0.002). The ultrasonic nebulizer was also associated with a reduction in the time required to complete nebulization (9 vs 21 min, respectively) (p<0.0001). Use of the DP100 ultrasonic nebulizer more than doubled lung deposition compared with the System 22 jet nebulizers in mechanically-ventilated patients. Their efficiency, speed of drug delivery, and compatibility with mechanical ventilator circuits make ultrasonic nebulizers potentially attractive for use during mechanical ventilation.

  19. Energy Impacts of Envelope Tightening and Mechanical Ventilation for the U.S. Residential Sector

    SciTech Connect

    Logue, J. M.; Sherman, M. H.; Walker, I. S.; Singer, B. C.

    2013-01-01

    Effective residential envelope air sealing reduces infiltration and associated energy costs for thermal conditioning, yet often creates a need for mechanical ventilation to protect indoor air quality. This study estimated the potential energy savings of implementing airtightness improvements or absolute standards along with mechanical ventilation throughout the U.S. housing stock. We used a physics-based modeling framework to simulate the impact of envelope tightening, providing mechanical ventilation as needed. There are 113 million homes in the US. We calculated the change in energy demand for each home in a nationally representative sample of 50,000 virtual homes developed from the 2009 Residential Energy Consumption Survey. Ventilation was provided as required by 2010 and proposed 2013 versions of ASHRAE Standard 62.2. Ensuring that all current homes comply with 62.2-2010 would increase residential site energy demand by 0.07 quads (0.07 exajoules (EJ)) annually. Improving airtightness of all homes at current average retrofit performance levels would decrease demand by 0.7 quads (0.74 EJ) annually and upgrading all homes to be as airtight as the top 10% of similar homes would double the savings, leading to roughly $22 billion in annual savings in energy bills. We also analyzed the potential benefits of bringing the entire stock to airtightness specifications of IECC 2012, Canada's R2000, and Passive House standards.

  20. Parameters affecting the tidal volume during expiratory abdominal compression in patients with prolonged tracheostomy mechanical ventilation

    PubMed Central

    Morino, Akira; Shida, Masahiro; Tanaka, Masashi; Sato, Kimihiro; Seko, Toshiaki; Ito, Shunsuke; Ogawa, Shunichi; Takahashi, Naoaki

    2015-01-01

    [Purpose] The aim of this study was to clarify physical parameters affecting the tidal volume during expiratory abdominal compression in patients with prolonged tracheostomy mechanical ventilation. [Methods] Eighteen patients with prolonged mechanical ventilation were included in this study. Expiratory abdominal compression was performed on patients lying in a supine position. The abdomen above the navel was vertically compressed in synchronization with expiration and released with inspiration. We measured the tidal volume during expiratory abdominal compression. [Results] The mean tidal volume during expiratory abdominal compression was higher than that at rest (430.6 ± 127.1 mL vs. 344.0 ± 94.3 mL). The tidal volume during expiratory abdominal compression was correlated with weight, days of ventilator support, dynamic compliance and abdominal expansion. Stepwise multiple regression analysis revealed that weight (β = 0.499), dynamic compliance (β = 0.387), and abdominal expansion (β = 0.365) were factors contributing to the tidal volume during expiratory abdominal compression. [Conclusion] Expiratory abdominal compression increased the tidal volume in patients with prolonged tracheostomy mechanical ventilation. The tidal volume during expiratory abdominal compression was influenced by each of the pulmonary conditions and the physical characteristics. PMID:26311947

  1. Ventilator-induced lung injury in preterm infants

    PubMed Central

    Carvalho, Clarissa Gutierrez; Silveira, Rita C; Procianoy, Renato Soibelmann

    2013-01-01

    In preterm infants, the need for intubation and mechanical ventilation is associated with ventilator-induced lung injuries and subsequent bronchopulmonary dysplasia. The aim of the present review was to improve the understanding of the mechanisms of injury that involve cytokine-mediated inflammation to contribute to the development of new preventive strategies. Relevant articles were retrieved from the PubMed database using the search terms "ventilator-induced lung injury preterm", "continuous positive airway pressure", "preterm", and "bronchopulmonary dysplasia". The resulting data and other relevant information were divided into several topics to ensure a thorough, critical view of ventilation-induced lung injury and its consequences in preterm infants. The role of pro-inflammatory cytokines (particularly interleukins 6 and 8 and tumor necrosis factor alpha) as mediators of lung injury was assessed. Evidence from studies conducted with animals and human newborns is described. This evidence shows that brief periods of mechanical ventilation is sufficient to induce the release of pro-inflammatory cytokines. Other forms of mechanical and non-invasive ventilation were also analyzed as protective alternatives to conventional mechanical ventilation. It was concluded that non-invasive ventilation, intubation followed by early surfactant administration and quick extubation for nasal continuous positive airway pressure, and strategies that regulate tidal volume and avoid volutrauma (such as volume guarantee ventilation) protect against ventilator-induced lung injury in preterm infants. PMID:24553514

  2. Effects of non-invasive ventilation on objective sleep and nocturnal respiration in patients with amyotrophic lateral sclerosis.

    PubMed

    Boentert, Matthias; Brenscheidt, Inga; Glatz, Christian; Young, Peter

    2015-09-01

    In amyotrophic lateral sclerosis (ALS), non-invasive ventilation (NIV) is indicated if sleep-disordered breathing (SDB), daytime hypercapnia, or significant diaphragmatic weakness is present. We investigated both short-term and long-term effects of NIV on objective measures of sleep and nocturnal respiration in patients with ALS. Polysomnography (PSG) and transcutaneous capnography were conducted for diagnosis of SDB (T0), for treatment initiation (T1), and follow-up 3, 9, and 15 months later (T2, T3, and T4, respectively). Records from 65 patients were retrospectively analyzed at T0 and T1. At subsequent timepoints, the number of full data sets decreased since follow-up sleep studies frequently included polygraphy rather than PSG (T2, 38 patients, T3, 17 patients, T4, 11 patients). At T0, mean age was 63.2 years, 29 patients were female, and 22 patients had bulbar ALS. Immediate sequelae of NIV initiation included significant increases of slow wave sleep, rapid eye movement sleep, and oxygen saturation. Mean apnea-hypopnea index, respiratory rate, and the maximum transcutaneous carbon dioxide tension were reduced. At T2-T4, normoxia and normocapnia were preserved. Sleep quality measures showed no alteration as diurnal use of NIV gradually increased reflecting disease progression. In contrast to previous reports, improvement of sleep and respiratory outcomes was found in both non-bulbar and bulbar patients. NIV significantly improves objective sleep quality and SDB in the first night of treatment in patients with bulbar and non-bulbar ALS. NIV warrants nocturnal normoventilation without deterioration of sleep quality in the long run with only minor changes to ventilator settings.

  3. Predicting Mechanical Ventilation and Mortality: Early and Late Indicators in Steven-Johnson Syndrome and Toxic Epidermal Necrolysis.

    PubMed

    Beck, Anna; Cooney, Ryan; Gamelli, Richard L; Mosier, Michael J

    2016-01-01

    Steven-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are characterized by loss of the epidermis, often accompanied by sloughing of the oral mucosa and airway, which may be associated with the need for mechanical ventilation. We retrospectively examined our SJS and TEN population for factors predictive of the need for mechanical ventilation and mortality. Over more than a 7-year period, 74 subjects of ≥18 years old with biopsy-confirmed SJS-TEN were identified. Variables within the first 3 days of admission and throughout the entire hospital stay were analyzed for their value in predicting the need for mechanical ventilation and mortality. Predictive variables were examined using univariate and multivariate logistic regression analyses. Of our 74 subjects, 28 (37.8%) required mechanical ventilation and 11 (13.9%) died, all of whom were intubated. Patients requiring ventilation had a significantly higher %TBSA loss of epidermis on admission and progressive epidermal loss after admission. On multivariate analysis, acute kidney injury within the first 3 days of admission and fewer days from symptom onset to admission were statistically significant in predicting need for mechanical ventilation. In addition, the early need for mechanical ventilation, early serum bicarbonate <20 mm/L, and older age were all associated with higher mortality on multivariate analysis. In conclusion, the need for mechanical ventilation in adult TEN subjects is associated with higher mortality. This is the first time that mechanical ventilation has been specifically examined in the recent U.S. SJS and TEN population. The early recognition of patients at risk for ventilation may help guide management, especially in those patients admitted early after symptom development with acute kidney injury and extensive, progressing epidermal loss.

  4. An experimental study on the impacts of inspiratory and expiratory muscles activities during mechanical ventilation in ARDS animal model

    PubMed Central

    Zhang, Xianming; Du, Juan; Wu, Weiliang; Zhu, Yongcheng; Jiang, Ying; Chen, Rongchang

    2017-01-01

    In spite of intensive investigations, the role of spontaneous breathing (SB) activity in ARDS has not been well defined yet and little has been known about the different contribution of inspiratory or expiratory muscles activities during mechanical ventilation in patients with ARDS. In present study, oleic acid-induced beagle dogs’ ARDS models were employed and ventilated with the same level of mean airway pressure. Respiratory mechanics, lung volume, gas exchange and inflammatory cytokines were measured during mechanical ventilation, and lung injury was determined histologically. As a result, for the comparable ventilator setting, preserved inspiratory muscles activity groups resulted in higher end-expiratory lung volume (EELV) and oxygenation index. In addition, less lung damage scores and lower levels of system inflammatory cytokines were revealed after 8 h of ventilation. In comparison, preserved expiratory muscles activity groups resulted in lower EELV and oxygenation index. Moreover, higher lung injury scores and inflammatory cytokines levels were observed after 8 h of ventilation. Our findings suggest that the activity of inspiratory muscles has beneficial effects, whereas that of expiratory muscles exerts adverse effects during mechanical ventilation in ARDS animal model. Therefore, for mechanically ventilated patients with ARDS, the demands for deep sedation or paralysis might be replaced by the strategy of expiratory muscles paralysis through epidural anesthesia. PMID:28230150

  5. An experimental study on the impacts of inspiratory and expiratory muscles activities during mechanical ventilation in ARDS animal model.

    PubMed

    Zhang, Xianming; Du, Juan; Wu, Weiliang; Zhu, Yongcheng; Jiang, Ying; Chen, Rongchang

    2017-02-23

    In spite of intensive investigations, the role of spontaneous breathing (SB) activity in ARDS has not been well defined yet and little has been known about the different contribution of inspiratory or expiratory muscles activities during mechanical ventilation in patients with ARDS. In present study, oleic acid-induced beagle dogs' ARDS models were employed and ventilated with the same level of mean airway pressure. Respiratory mechanics, lung volume, gas exchange and inflammatory cytokines were measured during mechanical ventilation, and lung injury was determined histologically. As a result, for the comparable ventilator setting, preserved inspiratory muscles activity groups resulted in higher end-expiratory lung volume (EELV) and oxygenation index. In addition, less lung damage scores and lower levels of system inflammatory cytokines were revealed after 8 h of ventilation. In comparison, preserved expiratory muscles activity groups resulted in lower EELV and oxygenation index. Moreover, higher lung injury scores and inflammatory cytokines levels were observed after 8 h of ventilation. Our findings suggest that the activity of inspiratory muscles has beneficial effects, whereas that of expiratory muscles exerts adverse effects during mechanical ventilation in ARDS animal model. Therefore, for mechanically ventilated patients with ARDS, the demands for deep sedation or paralysis might be replaced by the strategy of expiratory muscles paralysis through epidural anesthesia.

  6. A model-based decision support system for critiquing mechanical ventilation treatments.

    PubMed

    Tehrani, Fleur T; Abbasi, Soraya

    2012-06-01

    A computerized system for critiquing mechanical ventilation treatments is presented that can be used as an aide to the intensivist. The presented system is based on the physiological model of the subject's respiratory system. It uses modified versions of previously developed models of adult and neonatal respiratory systems to simulate the effects of different ventilator treatments on the patient's blood gases. The physiological models that have been used for research and teaching purposes by many researchers in the field include lungs, body tissue, and the brain tissue. The lung volume is continuously time-varying and the effects of shunt in the lung, changes in cardiac output and cerebral blood flow, and the arterial transport delays are included in the system. Evaluation tests were done on adult and neonate patients with different diagnoses. In both groups combined, the differences between the arterial partial pressures of CO(2) predicted by the system and the experimental values were 1.86 ± 1.6 mmHg (mean ± SD), and the differences between the predicted arterial hemoglobin oxygen saturation values, S(aO2), and the experimental values measured by using pulse oximetry, S(pO2), were 0.032 ± 0.02 (mean ± SD). The proposed system has the potential to be used alone or in combination with other decision support systems to set ventilation parameters and optimize treatment for patients on mechanical ventilation.

  7. Microbial composition and antibiotic resistance of biofilms recovered from endotracheal tubes of mechanically ventilated patients.

    PubMed

    Vandecandelaere, Ilse; Coenye, Tom

    2015-01-01

    In critically ill patients, breathing is impaired and mechanical ventilation, using an endotracheal tube (ET) connected to a ventilator, is necessary. Although mechanical ventilation is a life-saving procedure, it is not without risk. Because of several reasons, a biofilm often forms at the distal end of the ET and this biofilm is a persistent source of bacteria which can infect the lungs, causing ventilator-associated pneumonia (VAP). There is a link between the microbial flora of ET biofilms and the microorganisms involved in the onset of VAP. Culture dependent and independent techniques were already used to identify the microbial flora of ET biofilms and also, the antibiotic resistance of microorganisms obtained from ET biofilms was determined. The ESKAPE pathogens play a dominant role in the onset of VAP and these organisms were frequently identified in ET biofilms. Also, antibiotic resistant microorganisms were frequently present in ET biofilms. Members of the normal oral flora were also identified in ET biofilms but it is thought that these organisms initiate ET biofilm formation and are not directly involved in the development of VAP.

  8. The use of mechanical ventilation with heat recovery for controlling radon and radondaughter concentrations in houses

    NASA Astrophysics Data System (ADS)

    Nazaroff, W. W.; Boegel, M. L.; Hollowell, C. D.; Roseme, G. D.

    An energy research house in Maryland was found to have radon concentrations far in excess of recommended guidelines. A mechanical ventilation system with heat recovery was installed in this house to test its effectiveness as an energy-efficient control technique for indoor radon. Radon concentration was monitored continuously for 2 weeks under varying ventilation conditions [0.07-0.8 air changes per hour (ach)] and radondaughter concentrations were measured by grab-sample techniques about nine times daily during this period. At ventilation rates of 0.6 ach and higher, radon-daughter levels dropped below guidelines for indoor concentrations. Comparison with other studies indicates that indoor radon buildup may be a problem in a considerable portion of houses characterized by their low infiltration rates. The use of mechanical ventilation systems with air-to-air heat exchangers may offer a practical, cost-effective and energy-efficient means of alleviating not only the radon problem specifically but also the general deterioration of indoor air quality in many houses designed or retrofitted to achieve low infiltration.

  9. Mechanical ventilation in Coffin-Lowry syndrome: a case report

    PubMed Central

    de Moura, Edmilson Bastos; de Moura, Érica Leal Teixeira; Amorim, Fábio Ferreira; Oliveira, Vânia Maria

    2016-01-01

    We describe a 27-year-old patient with Coffin-Lowry syndrome with severe community pneumonia, septic shock and respiratory failure. We summarize both the mechanical ventilatory assistance and the hospitalization period in the intensive care unit. PMID:28099645

  10. Ventilator Associated Pneumonia in Children.

    PubMed

    Chang, Ivy; Schibler, Andreas

    2016-09-01

    Ventilator associated pneumonia (VAP) is a common complication in mechanically ventilated children and adults. There remains much controversy in the literature over the definition, treatment and prevention of VAP. The incidence of VAP is variable, depending on the definition used and can effect up to 12% of ventilated children. For the prevention and reduction of the incidence of VAP, ventilation care bundles are suggested, which include vigorous hand hygiene, head elevation and use of non-invasive ventilation strategies. Diagnosis is mainly based on the clinical presentation with a lung infection occurring after 48hours of mechanical ventilation requiring a change in ventilator settings (mainly increased oxygen requirement, a positive culture of a specimen taken preferentially using a sterile sampling technique either using a bronchoscope or a blind lavage of the airways). A new infiltrate on a chest X ray supports the diagnosis of VAP. For the treatment of VAP, initial broad-spectrum antibiotics should be used followed by a specific antibiotic therapy with a narrow target once the bacterium is confirmed.

  11. Non-invasive ventilation with intelligent volume-assured pressure support versus pressure-controlled ventilation: effects on the respiratory event rate and sleep quality in COPD with chronic hypercapnia

    PubMed Central

    Nilius, Georg; Katamadze, Nato; Domanski, Ulrike; Schroeder, Maik; Franke, Karl-Josef

    2017-01-01

    Background COPD patients who develop chronic hypercapnic respiratory failure have a poor prognosis. Treatment of choice, especially the best form of ventilation, is not well known. Objectives This study compared the effects of pressure-controlled (spontaneous timed [ST]) non-invasive ventilation (NIV) and NIV with intelligent volume-assured pressure support (IVAPS) in chronic hypercapnic COPD patients regarding the effects on alveolar ventilation, adverse patient/ventilator interactions and sleep quality. Methods This prospective, single-center, crossover study randomized patients to one night of NIV using ST then one night with the IVAPS function activated, or vice versa. Patients were monitored using polysomnography (PSG) and transcutaneous carbon dioxide pressure (PtcCO2) measurement. Patients rated their subjective experience (total score, 0–45; lower scores indicate better acceptability). Results Fourteen patients were included (4 females, age 59.4±8.9 years). The total number of respiratory events was low, and similar under pressure-controlled (5.4±6.7) and IVAPS (8.3±10.2) conditions (P=0.064). There were also no clinically relevant differences in PtcCO2 between pressure-controlled and IVAPS NIV (52.9±6.2 versus 49.1±6.4 mmHg). Respiratory rate was lower under IVAPS overall; between-group differences reached statistical significance during wakefulness and non-rapid eye movement sleep. Ventilation pressures were 2.6 cmH2O higher under IVAPS versus pressure-controlled ventilation, resulting in a 20.1 mL increase in breathing volume. Sleep efficiency was slightly higher under pressure-controlled ventilation versus IVAPS. Respiratory arousals were uncommon (24.4/h [pressure-controlled] versus 25.4/h [IVAPS]). Overall patient assessment scores were similar, although there was a trend toward less discomfort during IVAPS. Conclusion Our results show that IVAPS NIV allows application of higher nocturnal ventilation pressures versus ST without affecting sleep

  12. Role of the JNK pathway on the expression of inflammatory factors in alveolar macrophages under mechanical ventilation.

    PubMed

    Tong, Jin; Zhou, Xiang-Dong; Kolosov, Victor P; Perelman, Juliy M

    2013-11-01

    The aim of this study was to investigate the regulatory role of the c-JUN N-terminal kinase (JNK) pathway on interleukin (IL)-8 and tumor necrosis factor (TNF)-α expression in alveolar macrophages (AMs) of injured lung. Lung injury was induced in the New Zealand white rabbit by applying continuous mechanical ventilation with or without inhibitor of JNK (SP600125), p38 (SB203580), or ERK (PD98059). Non-ventilated rabbits (controls) were compared with the different ventilation-days groups, and untreated rabbits ventilated for 3 days (controls) were compared with the different inhibitor groups. We found that mechanical ventilation caused significant decreases in partial pressures of carbon dioxide (pCO2) and oxygen (pO2) of untreated rabbits (all times, P<0.05), but the inhibitor-treated groups showed no change in either blood-gas indicator (all times, P>0.05). Mechanical ventilation caused time-dependent increases in mRNA and protein levels of TNF-α and IL-8 in AMs and in serum of untreated rabbits, with the peak levels occurring at day 3 of ventilation. The SP600125-treated group showed significantly decreased TNF-α expression, but no significant change in IL-8 expression. Neither the SB203580- nor PD98059-treated groups showed any significant change in TNF-α or IL-8 expression. MAPKs' inhibitors could reduce mechanical ventilation-induced inflammation, and SP600125 produced the most robust decrease in inflammation. Mechanical ventilation-induced lung injury stimulates IL-8 and TNF-α expression in rabbit AMs in a time-dependent manner. The JNK pathway plays an important role in mechanical ventilation-stimulated TNF-α expression in AMs, but the injury-stimulated IL-8 expression may be regulated by other signaling pathways.

  13. Injury and repair in the very immature lung following brief mechanical ventilation.

    PubMed

    Brew, Nadine; Hooper, Stuart B; Allison, Beth J; Wallace, Megan J; Harding, Richard

    2011-12-01

    Mechanical ventilation (MV) of very premature infants contributes to lung injury and bronchopulmonary dysplasia (BPD), the effects of which can be long-lasting. Little is currently known about the ability of the very immature lung to recover from ventilator-induced lung injury. Our objective was to determine the ability of the injured very immature lung to repair in the absence of continued ventilation and to identify potential mechanisms. At 125 days gestational age (days GA, 0.85 of term), fetal sheep were partially exposed by hysterotomy under anesthesia and aseptic conditions; they were intubated and ventilated for 2 h with an injurious MV protocol and then returned to the uterus to continue development. Necropsy was performed at either 1 day (short-term group, 126 days GA, n = 6) or 15 days (long-term group, 140 days GA, n = 5) after MV; controls were unventilated (n = 7-8). At 1 day after MV, lungs displayed signs of injury, including hemorrhage, disorganized elastin and collagen deposition in the distal airspaces, altered morphology, significantly reduced secondary septal crest density, and decreased airspace. Bronchioles had thickened epithelium with evidence of injury and sloughing. Relative mRNA levels of early response genes (connective tissue growth factor, cysteine-rich 61, and early growth response-1) and proinflammatory cytokines [interleukins (IL)-1β, IL-6, IL-8, tumor necrosis factor-α, and transforming growth factor-β] were not different between groups 1 day after MV. At 15 days after MV, lung structure was normal with no evidence of injury. We conclude that 2 h of MV induces severe injury in the very immature lung and that these lungs have the capacity to repair spontaneously in the absence of further ventilation.

  14. Neonatal total liquid ventilation: is low-frequency forced oscillation technique suitable for respiratory mechanics assessment?

    PubMed

    Bossé, Dominick; Beaulieu, Alexandre; Avoine, Olivier; Micheau, Philippe; Praud, Jean-Paul; Walti, Hervé

    2010-08-01

    This study aimed to implement low-frequency forced oscillation technique (LFFOT) in neonatal total liquid ventilation (TLV) and to provide the first insight into respiratory impedance under this new modality of ventilation. Thirteen newborn lambs, weighing 2.5 + or - 0.4 kg (mean + or - SD), were premedicated, intubated, anesthetized, and then placed under TLV using a specially design liquid ventilator and a perfluorocarbon. The respiratory mechanics measurements protocol was started immediately after TLV initiation. Three blocks of measurements were first performed: one during initial respiratory system adaptation to TLV, followed by two other series during steady-state conditions. Lambs were then divided into two groups before undergoing another three blocks of measurements: the first group received a 10-min intravenous infusion of salbutamol (1.5 microg x kg(-1) x min(-1)) after continuous infusion of methacholine (9 microg x kg(-1) x min(-1)), while the second group of lambs was chest strapped. Respiratory impedance was measured using serial single-frequency tests at frequencies ranging between 0.05 and 2 Hz and then fitted with a constant-phase model. Harmonic test signals of 0.2 Hz were also launched every 10 min throughout the measurement protocol. Airway resistance and inertance were starkly increased in TLV compared with gas ventilation, with a resonant frequency < or = 1.2 Hz. Resistance of 0.2 Hz and reactance were sensitive to bronchoconstriction and dilation, as well as during compliance reduction. We report successful implementation of LFFOT to neonatal TLV and present the first insight into respiratory impedance under this new modality of ventilation. We show that LFFOT is an effective tool to track respiratory mechanics under TLV.

  15. AUTOPILOT-BT: a system for knowledge and model based mechanical ventilation.

    PubMed

    Lozano, S; Möller, K; Brendle, A; Gottlieb, D; Schumann, S; Stahl, C A; Guttmann, J

    2008-01-01

    A closed-loop system (AUTOPILOT-BT) for the control of mechanical ventilation was designed to: 1) autonomously achieve goals specified by the clinician, 2) optimize the ventilator settings with respect to the underlying disease and 3) automatically adapt to the individual properties and specific disease status of the patient. The current realization focuses on arterial oxygen saturation (SpO(2)), end-tidal CO(2) pressure (P(et)CO(2)), and positive end-expiratory pressure (PEEP) maximizing respiratory system compliance (C(rs)). The "AUTOPILOT-BT" incorporates two different knowledge sources: a fuzzy logic control reflecting expert knowledge and a mathematical model based system that provides individualized patient specific information. A first evaluation test with respect to desired end-tidal-CO(2)-level was accomplished using an experimental setup to simulate three different metabolic CO(2) production rates by means of a physical lung simulator. The outcome of ventilator settings made by the "AUTOPILOT-BT" system was compared to those produced by clinicians. The model based control system proved to be superior to the clinicians as well as to a pure fuzzy logic based control with respect to precision and required settling time into the optimal ventilation state.

  16. The role of endocrine mechanisms in ventilator-associated lung injury in critically ill patients.

    PubMed

    Penesova, A; Galusova, A; Vigas, M; Vlcek, M; Imrich, R; Majek, M

    2012-07-01

    The critically ill subjects are represented by a heterogeneous group of patients suffering from a life-threatening event of different origin, e.g. trauma, cardiopulmonary failure, surgery or sepsis. The majority of these patients are dependent on the artificial lung ventilation, which means a life-saving chance for them. However, the artificial lung ventilation may trigger ventilation-associated lung injury (VALI). The mechanical ventilation at higher volumes (volutrauma) and pressure (barotrauma) can cause histological changes in the lungs including impairments in the gap and adherens junctions and desmosomes. The injured lung epithelium may lead to an impairment of the surfactant production and function, and this may not only contribute to the pathophysiology of VALI but also to acute respiratory distress syndrome. Other components of VALI are atelectrauma and toxic effects of the oxygen. Collectively, all these effects may result in a lung inflammation associated with a subsequent profibrotic changes, endothelial dysfunction, and activation of the local and systemic endocrine responses such as the renin-angiotensin system (RAS). The present review is aimed to describe some of the pathophysiologic aspects of VALI providing a basis for novel therapeutic strategies in the critically ill patients.

  17. Successful Treatment of Carcinomatous Central Airway Obstruction with Bronchoscopic Electrocautery Using Hot Biopsy Forceps during Mechanical Ventilation.

    PubMed

    Ugajin, Motoi; Kani, Hisanori

    2017-01-01

    We report the case of a 72-year-old man with occlusion of the left main bronchus due to squamous cell carcinoma of the lung. He required tracheal intubation and mechanical ventilation because of the aggravation of atelectasis and obstructive pneumonia. Electrocautery using hot biopsy forceps was performed during mechanical ventilation with a 40% fraction of inspired oxygen. He was extubated following improvement in the atelectasis and obstructive pneumonia and discharged with shrinkage of the tumor after chemotherapy. We describe a safe electrocautery procedure using hot biopsy forceps during mechanical ventilation with reference to previous reports.

  18. Successful Treatment of Carcinomatous Central Airway Obstruction with Bronchoscopic Electrocautery Using Hot Biopsy Forceps during Mechanical Ventilation

    PubMed Central

    Kani, Hisanori

    2017-01-01

    We report the case of a 72-year-old man with occlusion of the left main bronchus due to squamous cell carcinoma of the lung. He required tracheal intubation and mechanical ventilation because of the aggravation of atelectasis and obstructive pneumonia. Electrocautery using hot biopsy forceps was performed during mechanical ventilation with a 40% fraction of inspired oxygen. He was extubated following improvement in the atelectasis and obstructive pneumonia and discharged with shrinkage of the tumor after chemotherapy. We describe a safe electrocautery procedure using hot biopsy forceps during mechanical ventilation with reference to previous reports. PMID:28373918

  19. Effect of endotracheal suction on lung dynamics in mechanically-ventilated paediatric patients.

    PubMed

    Morrow, Brenda; Futter, Merle; Argent, Andrew

    2006-01-01

    Endotracheal suctioning is performed regularly in ventilated infants and children to remove obstructive secretions. The effect of suctioning on respiratory mechanics is not known. This study aimed to determine the immediate effect of endotracheal suctioning on dynamic lung compliance, tidal volume, and airway resistance in mechanically-ventilated paediatric patients by means of a prospective observational clinical study. Lung mechanics were recorded for five minutes before and five minutes after a standardised suctioning procedure in 78 patients intubated with endotracheal tubes < or = 4.0 mm internal diameter. Twenty-four patients with endotracheal tube leaks > or = 20% were excluded from analysis. There was a significant overall decrease in dynamic compliance (p < 0.001) and mechanical expired tidal volume (p = 0.03) following suctioning with no change in the percentage endotracheal tube leak (p = 0.41). The change in dynamic compliance was directly related to both endotracheal tube and catheter sizes. There was no significant change in expiratory or inspiratory airway resistance following suctioning (p > 0.05). Although the majority of patients (68.5%) experienced a drop in dynamic compliance following suctioning, dynamic compliance increased in 31.5% of patients after the procedure. This study demonstrates that endotracheal suctioning frequently causes an immediate drop in dynamic compliance and expired tidal volume in ventilated children with variable lung pathology, intubated with small endotracheal tubes, probably indicating loss of lung volume caused by the suctioning procedure. There is no evidence that suctioning reduces airway resistance.

  20. Mechanical ventilation in acute respiratory distress syndrome: The open lung revisited.

    PubMed

    Amado-Rodríguez, L; Del Busto, C; García-Prieto, E; Albaiceta, G M

    2017-02-23

    Acute respiratory distress syndrome (ARDS) is still related to high mortality and morbidity rates. Most patients with ARDS will require ventilatory support. This treatment has a direct impact upon patient outcome and is associated to major side effects. In this regard, ventilator-associated lung injury (VALI) is the main concern when this technique is used. The ultimate mechanisms of VALI and its management are under constant evolution. The present review describes the classical mechanisms of VALI and how they have evolved with recent findings from physiopathological and clinical studies, with the aim of analyzing the clinical implications derived from them. Lastly, a series of knowledge-based recommendations are proposed that can be helpful for the ventilator assisted management of ARDS at the patient bedside.

  1. Pulsed Dose Delivery of Oxygen in Mechanically Ventilated Pigs with Acute Lung Injury

    DTIC Science & Technology

    2013-03-01

    atropine (0.54 mg/kg). They were then intubated with 7.5 French endotracheal tubes. A surgical plane of anesthesia was maintained with isoflurane...patients often require intubation and mechanical ventilation with supplemental oxygen and positive end-expiratory pressure (PEEP). To date, the...circuit, directly at the endotracheal tube. We used the SeQual Eclipse II, which was selected for its oxygen generating capabilities, as it is capable

  2. Can dead space fraction predict the length of mechanical ventilation in exacerbated COPD patients?

    PubMed Central

    Farah, Raymond; Makhoul, Nicola

    2009-01-01

    Background Chronic obstructive pulmonary disease (COPD) is a condition in which there is limited airflow during expiration (exhaling, or breathing out) that is not fully reversible and usually worsens over time. The disease is estimated to kill more than 100,000 Americans each year, and costs related to care of patients with COPD are significant. Physiologically, COPD represents a disruption in ventilation and in the exchange of gases in the lungs. Laboratory tests indicate elevated CO2 levels, gradual reduction of the levels of oxygen and pH in arterial blood, and a consequent rise in the dead space fraction (DSF) of the lungs. Objective Patients with COPD exacerbation represent a large portion of those artificially ventilated. In an attempt to develop a prognostic tool for length of treatment, we compared the proportion of DSF to the length of mechanical ventilation (MV). Methods This study included 73 patients admitted to the intensive care unit (ICU) where they received MV due to exacerbation of COPD. Each patient’s arterial blood gases (ABG) were measured upon admission. PeCO2 was tested using a Datex S/5 instrument. Subsequently, DSF was calculated using the Bohr equation. Statistical data was analyzed using SPSS software. Results Patients included in the study were ventilated from 6 to 160 hours (average 40 ± 47). In addition to ABG measurements, PeCO2 (expired CO2) levels were measured and DSF calculated for each patient. DSF values varied from 0.21 to 0.76 (average 0.119 ± 0.489). No correlation was found between DSF and length of artificial ventilation. Conclusion Evaluation of DSF does not provide a factor in estimating the length of treatment for patients with acute respiratory failure due to COPD exacerbation. PMID:20037683

  3. Effectiveness of an inspiratory pressure-limited approach to mechanical ventilation in septic patients.

    PubMed

    Martin-Loeches, Ignacio; de Haro, Candelaria; Dellinger, R Phillip; Ferrer, Ricard; Phillips, Gary S; Levy, Mitchell M; Artigas, Antonio

    2013-01-01

    Severe sepsis is one of the most common causes of acute lung injury (ALI) and is associated with high mortality. The aim of the study was to see whether a protective strategy based approach with a plateau pressure <30 cmH(2)O was associated with lower mortality in septic patients with ALI in the Surviving Sepsis Campaign international database. A retrospective analysis of an international multicentric database of 15,022 septic patients from 165 intensive care units was used. Septic patients with ALI and mechanical ventilation (n=1,738) had more accompanying organ dysfunction and a higher mortality rate (48.3% versus 33.0%, p<0.001) than septic patients without ALI (n=13,284). In patients with ALI and mechanical ventilation, the use of inspiratory plateau pressures maintained at <30 cmH(2)O was associated with lower mortality by Chi-squared test (46.4% versus 55.1%, p<0.001) and by Kaplan-Meier and log-rank test (p<0.001). In a multivariable random-effects Cox regression, plateau pressure <30 cmH(2)O was significantly associated with lower mortality (hazard ratio 0.84, 95% CI 0.72-0.99; p=0.038). ALI in sepsis was associated with higher mortality, especially when an inspiratory pressure-limited mechanical ventilation approach was not implemented.

  4. Holistic Care for Patients During Weaning from Mechanical Ventilation: A Qualitative Study

    PubMed Central

    Khalafi, Ali; Elahi, Nasrin; Ahmadi, Fazlollah

    2016-01-01

    Background Weaning patients from mechanical ventilation is a complex and highly challenging process. It requires continuity of care, the overall assessment of patients, and a focus on all aspects of patients’ needs by critical care nurses. Objectives The aim of the present study was to explore holistic care while patients are being weaned from mechanical ventilation from the perspective of the critical care nurses. Methods The study was carried out in the intensive care units (ICUs) of six hospitals in Ahvaz, Iran, from 2014 to 2015. In this qualitative study, 25 ICU staff including nurses, nurse managers, and nurse educators were selected by means of purposive sampling. Semi-structured interviews were used for data collection. The interview transcripts were then analyzed using qualitative content analysis. Results The four main themes that emerged to explain nurses’ experiences of holistic care when weaning patients from mechanical ventilation include continuous care, a holistic overview of the patient, promoting human dignity, and the overall development of well-being. Conclusions It was found that avoiding routine pivotal expertise, increasing consciousness of the nonphysical aspects of patients while providing treatment and presenting exclusive care, utilizing experienced ICU nurses, and placing more emphasis on effective communication with patients in order to honor them as human beings can all enhance the holistic quality of care. PMID:28191345

  5. Novel method for conscious airway resistance and ventilation estimation in neonatal rodents using plethysmography and a mechanical lung.

    PubMed

    Zhang, Boyang; McDonald, Fiona B; Cummings, Kevin J; Frappell, Peter B; Wilson, Richard J A

    2014-09-15

    In unrestrained whole body plethysmography, tidal volume is commonly determined using the barometric method, which assumes that temperature and humidity changes (the 'barometric component') are solely responsible for breathing-related chamber pressure fluctuations. However, in small animals chamber pressure is also influenced by a 'mechanical component' dependent on airway resistance and airflow. We devised a novel 'mechanical lung' capable of simulating neonatal mouse breathing in the absence of temperature or humidity changes. Using this device, we confirm that the chamber pressure fluctuations produced by breathing of neonatal mice are dominated by the mechanical component, precluding direct quantitative assessment of tidal volume. Recognizing the importance of airway resistance to the chamber pressure signal and the ability of our device to simulate neonatal breathing at different frequencies and tidal volumes, we invented a novel in vivo, non-invasive method for conscious airway resistance and ventilation estimation (CARVE) in neonatal rodents. This technique will allow evaluation of developmental, pathological and pharmaceutical effects on airway resistance.

  6. Simulation of swallowing dysfunction and mechanical ventilation after a Montgomery T-tube insertion.

    PubMed

    Trabelsi, O; Malvè, M; Mena Tobar, A; Doblaré, M

    2015-01-01

    The Montgomery T-tube is used as a combined tracheal stent and airway after laryngotracheoplasty, to keep the lumen open and prevent mucosal laceration from scarring. It is valuable in the management of upper and mid-tracheal lesions, while invaluable in long and multisegmental stenting lesions. Numerical simulations based on real-patient-tracheal geometry, experimental tissue characterization, and previous numerical estimation of the physiological swallowing force are performed to estimate the consequences of Montgomery T-tube implantation on swallowing and assisted ventilation: structural analysis of swallowing is performed to evaluate patient swallowing capacity, and computational fluid dynamics simulation is carried out to analyze related mechanical ventilation. With an inserted Montgomery T-tube, vertical displacement (Z-axis) reaches 8.01 mm, whereas in the Y-axis, it reaches 6.63 mm. The maximal principal stress obtained during swallowing was 1.6 MPa surrounding the hole and in the upper contact with the tracheal wall. Fluid flow simulation of the mechanical ventilation revealed positive pressure for both inhalation and exhalation, being higher for inspiration. The muscular deflections, considerable during normal breathing, are nonphysiological, and this aspect results in a constant overload of the tracheal muscle. During swallowing, the trachea ascends producing a nonhomogeneous elongation. This movement can be compromised when prosthesis is inserted, which explains the high incidence of glottis close inefficiency. Fluid simulations showed that nonphysiological pressure is established inside the trachea due to mechanical ventilation. This may lead to an overload of the tracheal muscle, explaining several related problems as muscle thinning or decrease in contractile function.

  7. Prospective Multicenter Study of Children With Bronchiolitis Requiring Mechanical Ventilation

    PubMed Central

    Piedra, Pedro A.; Stevenson, Michelle D.; Sullivan, Ashley F.; Forgey, Tate F.; Clark, Sunday; Espinola, Janice A.; Camargo, Carlos A.

    2012-01-01

    OBJECTIVE: To identify factors associated with continuous positive airway pressure (CPAP) and/or intubation for children with bronchiolitis. METHODS: We performed a 16-center, prospective cohort study of hospitalized children aged <2 years with bronchiolitis. For 3 consecutive years from November 1 until March 31, beginning in 2007, researchers collected clinical data and a nasopharyngeal aspirate from study participants. We oversampled children from the ICU. Samples of nasopharyngeal aspirate were tested by polymerase chain reaction for 18 pathogens. RESULTS: There were 161 children who required CPAP and/or intubation. The median age of the overall cohort was 4 months; 59% were male; 61% white, 24% black, and 36% Hispanic. In the multivariable model predicting CPAP/intubation, the significant factors were: age <2 months (odds ratio [OR] 4.3; 95% confidence interval [CI] 1.7–11.5), maternal smoking during pregnancy (OR 1.4; 95% CI 1.1–1.9), birth weight <5 pounds (OR 1.7; 95% CI 1.0–2.6), breathing difficulty began <1 day before admission (OR 1.6; 95% CI 1.2–2.1), presence of apnea (OR 4.8; 95% CI 2.5–8.5), inadequate oral intake (OR 2.5; 95% CI 1.3–4.3), severe retractions (OR 11.1; 95% CI 2.4–33.0), and room air oxygen saturation <85% (OR 3.3; 95% CI 2.0–4.8). The optimism-corrected c-statistic for the final model was 0.80. CONCLUSIONS: In this multicenter study of children hospitalized with bronchiolitis, we identified several demographic, historical, and clinical factors that predicted the use of CPAP and/or intubation, including children born to mothers who smoked during pregnancy. We also identified a novel subgroup of children who required mechanical respiratory support <1 day after respiratory symptoms began. PMID:22869823

  8. Mechanical ventilation alone, and in the presence of sepsis, impair protein metabolism in the diaphragm of neonatal pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mechanical ventilation (MV) impairs diaphragmatic function and diminishes the ability to wean from ventilatory support in adult humans. In normal neonatal pigs, animals that are highly anabolic, endotoxin (LPS) infusion induces sepsis, reduces peripheral skeletal muscle protein synthesis rates, but ...

  9. Portable power supply for continuous mechanical ventilation during intrahospital transport of critically ill patients with ARDS.

    PubMed

    Barton, A C; Tuttle-Newhall, J E; Szalados, J E

    1997-08-01

    Patients with respiratory failure and poor pulmonary compliance requiring high levels of positive pressure ventilation are at high risk during intrahospital transportation. Most ICU ventilators currently do not have a built-in power supply. Manual bag-valve ventilation frequently is used but often without optimum mean airway pressures or minute ventilation guarantees. Transport ventilators also are limited in their ability to provide high positive end-expiratory pressure, variable inspiratory-expiratory ratios, or pressure-controlled ventilation. The 3M SARNS HELP (Hospital Emergency Limited Power) 115, a portable battery, provides continuous power to ICU ventilators and eliminates ventilator circuit interruption for the critical period of patient transportation.

  10. Respiratory mechanics and plasma levels of tumor necrosis factor alpha and interleukin 6 are affected by gas humidification during mechanical ventilation in dogs.

    PubMed

    Hernández-Jiménez, Claudia; García-Torrentera, Rogelio; Olmos-Zúñiga, J Raúl; Jasso-Victoria, Rogelio; Gaxiola-Gaxiola, Miguel O; Baltazares-Lipp, Matilde; Gutiérrez-González, Luis H

    2014-01-01

    The use of dry gases during mechanical ventilation has been associated with the risk of serious airway complications. The goal of the present study was to quantify the plasma levels of TNF-alpha and IL-6 and to determine the radiological, hemodynamic, gasometric, and microscopic changes in lung mechanics in dogs subjected to short-term mechanical ventilation with and without humidification of the inhaled gas. The experiment was conducted for 24 hours in 10 dogs divided into two groups: Group I (n = 5), mechanical ventilation with dry oxygen dispensation, and Group II (n = 5), mechanical ventilation with oxygen dispensation using a moisture chamber. Variance analysis was used. No changes in physiological, hemodynamic, or gasometric, and radiographic constants were observed. Plasma TNF-alpha levels increased in group I, reaching a maximum 24 hours after mechanical ventilation was initiated (ANOVA p = 0.77). This increase was correlated to changes in mechanical ventilation. Plasma IL-6 levels decreased at 12 hours and increased again towards the end of the study (ANOVA p>0.05). Both groups exhibited a decrease in lung compliance and functional residual capacity values, but this was more pronounced in group I. Pplat increased in group I (ANOVA p = 0.02). Inhalation of dry gas caused histological lesions in the entire respiratory tract, including pulmonary parenchyma, to a greater extent than humidified gas. Humidification of inspired gases can attenuate damage associated with mechanical ventilation.

  11. Respiratory Mechanics and Plasma Levels of Tumor Necrosis Factor Alpha and Interleukin 6 Are Affected by Gas Humidification during Mechanical Ventilation in Dogs

    PubMed Central

    Hernández-Jiménez, Claudia; García-Torrentera, Rogelio; Olmos-Zúñiga, J. Raúl; Jasso-Victoria, Rogelio; Gaxiola-Gaxiola, Miguel O.; Baltazares-Lipp, Matilde; Gutiérrez-González, Luis H.

    2014-01-01

    The use of dry gases during mechanical ventilation has been associated with the risk of serious airway complications. The goal of the present study was to quantify the plasma levels of TNF-alpha and IL-6 and to determine the radiological, hemodynamic, gasometric, and microscopic changes in lung mechanics in dogs subjected to short-term mechanical ventilation with and without humidification of the inhaled gas. The experiment was conducted for 24 hours in 10 dogs divided into two groups: Group I (n = 5), mechanical ventilation with dry oxygen dispensation, and Group II (n = 5), mechanical ventilation with oxygen dispensation using a moisture chamber. Variance analysis was used. No changes in physiological, hemodynamic, or gasometric, and radiographic constants were observed. Plasma TNF-alpha levels increased in group I, reaching a maximum 24 hours after mechanical ventilation was initiated (ANOVA p = 0.77). This increase was correlated to changes in mechanical ventilation. Plasma IL-6 levels decreased at 12 hours and increased again towards the end of the study (ANOVA p>0.05). Both groups exhibited a decrease in lung compliance and functional residual capacity values, but this was more pronounced in group I. Pplat increased in group I (ANOVA p = 0.02). Inhalation of dry gas caused histological lesions in the entire respiratory tract, including pulmonary parenchyma, to a greater extent than humidified gas. Humidification of inspired gases can attenuate damage associated with mechanical ventilation. PMID:25036811

  12. Mechanical ventilation and intra-abdominal hypertension: 'Beyond Good and Evil'

    PubMed Central

    2012-01-01

    Intra-abdominal hypertension is frequent in surgical and medical critically ill patients. Intra-abdominal hypertension has a serious impact on the function of respiratory as well as peripheral organs. In the presence of alveolar capillary damage, which occurs in acute respiratory distress syndrome (ARDS), intra-abdominal hypertension promotes lung injury as well as edema, impedes the pulmonary lymphatic drainage, and increases intra-thoracic pressures, leading to atelectasis, airway closure, and deterioration of respiratory mechanics and gas exchange. The optimal setting of mechanical ventilation and its impact on respiratory function and hemodynamics in ARDS associated with intra-abdominal hypertension are far from being assessed. We suggest that the optimal ventilator management of patients with ARDS and intra-abdominal hypertension would include the following: (a) intra-abdominal, esophageal pressure, and hemodynamic monitoring; (b) ventilation setting with protective tidal volume, recruitment maneuver, and level of positive end-expiratory pressure set according to the 'best' compliance of the respiratory system or the lung; (c) deep sedation with or without neuromuscular paralysis in severe ARDS; and (d) open abdomen in selected patients with severe abdominal compartment syndrome. PMID:23256904

  13. Patterns of home mechanical ventilation use in Europe: results from the Eurovent survey.

    PubMed

    Lloyd-Owen, S J; Donaldson, G C; Ambrosino, N; Escarabill, J; Farre, R; Fauroux, B; Robert, D; Schoenhofer, B; Simonds, A K; Wedzicha, J A

    2005-06-01

    The study was designed to assess the patterns of use of home mechanical ventilation (HMV) for patients with chronic respiratory failure across Europe. A detailed questionnaire of centre details, HMV user characteristics and equipment choices was sent to carefully identified HMV centres in 16 European countries. A total of 483 centres treating 27,118 HMV users were identified. Of these, 329 centres completed surveys between July 2001 and June 2002, representing up to 21,526 HMV users and a response rate of between 62% and 79%. The estimated prevalence of HMV in Europe was 6.6 per 100,000 people. The variation in prevalence between countries was only partially related to the median year of starting HMV services. In addition, there were marked differences between countries in the relative proportions of lung and neuromuscular patients using HMV, and the use of tracheostomies in lung and neuromuscular HMV users. Lung users were linked to a HMV duration of <1 yr, thoracic cage users with 6-10 yrs of ventilation and neuromuscular users with a duration of > or =6 yrs. In conclusion, wide variations exist in the patterns of home mechanical ventilation provision throughout Europe. Further work is needed to monitor its use and ensure equality of provision and access.

  14. Candidemia in the critically ill: initial therapy and outcome in mechanically ventilated patients

    PubMed Central

    2013-01-01

    Background Mortality among critically ill patients with candidemia is very high. We sought to determine whether the choice of initial antifungal therapy is associated with survival among these patients, using need for mechanical ventilatory support as a marker of critical illness. Methods Cohort analysis of outcomes among mechanically ventilated patients with candidemia from the 24 North American academic medical centers contributing to the Prospective Antifungal Therapy (PATH) Alliance registry. Patients were included if they received either fluconazole or an echinocandin as initial monotherapy. Results Of 5272 patients in the PATH registry at the time of data abstraction, 1014 were ventilated and concomitantly had candidemia, with 689 eligible for analysis. 28-day survival was higher among the 374 patients treated initially with fluconazole than among the 315 treated with an echinocandin (66% versus 51%, P < .001). Initial fluconazole therapy remained associated with improved survival after adjusting for non-treatment factors in the overall population (hazard ratio .75, 95% CI .59–.96), and also among patients with albicans infection (hazard ratio .62, 95% CI .44–.88). While not statistically significant, fluconazole appeared to be associated with higher mortality among patients infected with glabrata (HR 1.13, 95% CI .70–1.84). Conclusions Among ventilated patients with candidemia, those receiving fluconazole as initial monotherapy were significantly more likely to survive than those treated with an echinocandin. This difference persisted after adjustment for non-treatment factors. PMID:24172136

  15. Inspiratory muscle training to facilitate weaning from mechanical ventilation: protocol for a systematic review

    PubMed Central

    2011-01-01

    Background In intensive care, weaning is the term used for the process of withdrawal of mechanical ventilation to enable spontaneous breathing to be re-established. Inspiratory muscle weakness and deconditioning are common in patients receiving mechanical ventilation, especially that of prolonged duration. Inspiratory muscle training could limit or reverse these unhelpful sequelae and facilitate more rapid and successful weaning. Methods This review will involve systematic searching of five electronic databases to allow the identification of randomised trials of inspiratory muscle training in intubated and ventilated patients. From these trials, we will extract available data for a list of pre-defined outcomes, including maximal inspiratory pressure, the duration of the weaning period, and hospital length of stay. We will also meta-analyse comparable results where possible, and report a summary of the available pool of evidence. Discussion The data generated by this review will be the most comprehensive answer available to the question of whether inspiratory muscle training is clinically useful in intensive care. As well as informing clinicians in the intensive care setting, it will also inform healthcare managers deciding whether health professionals with skills in respiratory therapy should be made available to provide this sort of intervention. Through the publication of this protocol, readers will ultimately be able to assess whether the review was conducted according to a pre-defined plan. Researchers will be aware that the review is underway, thereby avoid duplication, and be able to use it as a basis for planning similar reviews. PMID:21835031

  16. Thenar oxygen saturation during weaning from mechanical ventilation: an observational study.

    PubMed

    Gruartmoner, Guillem; Mesquida, Jaume; Masip, Jordi; Martínez, Maria L; Villagra, Ana; Baigorri, Francisco; Pinsky, Michael R; Artigas, Antonio

    2014-01-01

    Our aim was to determine whether thenar tissue oxygen saturation (S(tO2)), measured by noninvasive near-infrared spectroscopy, and its changes derived from an ischaemic challenge are associated with weaning outcome. Our study comprised a prospective observational study in a 26-bed medical-surgical intensive care unit. Patients receiving mechanical ventilation for >48 h, and considered ready to wean by their physicians underwent a 30-min weaning trial. S(tO2) was measured continuously on the thenar eminence. A transient vascular occlusion test was performed prior to and at the end of the 30-min weaning trial, in order to obtain S(tO2) deoxygenation and reoxygenation rates, and estimated local oxygen consumption. 37 patients were studied. Patients were classified as weaning success (n=24) or weaning failure (n=13). No significant demographic, respiratory or haemodynamic differences were observed between the groups at inclusion. Patients who failed the overall weaning process showed a significant increase in deoxygenation and in local oxygen consumption from baseline to 30 min of weaning trial, whereas no significant changes were observed in the weaning success group. Failure to wean from mechanical ventilation was associated with higher relative increases in deoxygenation after 30 min of spontaneous ventilation.

  17. Effectiveness of new sedation and rehabilitation methods for critically ill patients receiving mechanical ventilation

    PubMed Central

    Yamashita, Kouji; Takami, Akiyoshi; Wakayama, Saichi; Makino, Misato; Takeyama, Yoshihiro

    2017-01-01

    [Purpose] The purpose of this study was to investigate the effects of new sedation management methods and cooperation between nurses and physical therapists on the duration of mechanical ventilation and hospitalization. [Subjects and Methods] Patients who had been treated at the study hospital 2 years before and after the implementation of the new methods were analyzed retrospectively and classified into a “control group” and an “intervention group”, respectively. Both groups were analyzed and subsequently compared regarding the effects of the new sedation and cooperative rehabilitation. [Results] A total of 70 patients met the inclusion criteria and were divided evenly into the two groups. No significant differences were found between the groups in age, APACHE II score, or duration of stay in hospital. On the other hand, significant decreases were seen in the duration of sedation and intubation, mechanical ventilation, and stay in the emergency ward, as well as time until standing. In addition, after intervention, three patients undergoing ventilator treatment were able to be ambulated. [Conclusion] These results suggest that the new sedation and cooperative rehabilitation methods for critically ill patients were effective in the early stage of treatment and shortened the duration of stay in the ward. PMID:28210060

  18. Mechanical Ventilator for Delivery of 17O2 in Brief Pulses

    PubMed Central

    Baumgardner, J.E; Mellon, E.A; Tailor, D.R; Mallikarjunarao, K; Borthakur, A; Reddy, R

    2008-01-01

    The 17O nucleus has been used recently by several groups for magnetic resonance (MR) imaging of cerebral metabolism. Inhalational delivery of 17O2 in very brief pulses could, in theory, have significant advantages for determination of the cerebral metabolic rate for oxygen (CMRO2) with MR imaging. Mechanical ventilators, however, are not typically capable of creating step changes in gas concentration at the airway. We designed a ventilator for large animal and human studies that provides mechanical ventilation to a subject inside an MR scanner through 25 feet of small-bore connecting tubing, and tested its capabilities using helium as a surrogate for 17O2. After switching the source gas from oxygen to helium, the 0-90% response time for helium concentration changes at the airway was 2.4 seconds. The capability for creating rapid step changes in gas concentration at the airway in large animal and human studies should facilitate the experimental testing of the delivery 17O2 in brief pulses, and its potential use in imaging CMRO2. PMID:19662118

  19. Individuality of breathing patterns in patients under noninvasive mechanical ventilation evidenced by chaotic global models

    NASA Astrophysics Data System (ADS)

    Letellier, Christophe; Rodrigues, Giovani G.; Muir, Jean-François; Aguirre, Luis A.

    2013-03-01

    Autonomous global models based on radial basis functions were obtained from data measured from patients under noninvasive mechanical ventilation. Some of these models, which are discussed in the paper, turn out to have chaotic or quasi-periodic solutions, thus providing a first piece of evidence that the underlying dynamics of the data used to estimate the global models are likely to be chaotic or, at least, have a chaotic component. It is explicitly shown that one of such global models produces attractors characterized by a Horseshoe map, two models produce toroidal chaos, and one model produces a quasi-periodic regime. These topologically inequivalent attractors evidence the individuality of breathing profiles observed in patient under noninvasive ventilation.

  20. The need for mechanical ventilation in a child exposed to a laundry detergent pod.

    PubMed

    Kamit-Can, Fulya; Alparslan, Caner; Anıl, Ayşe Berna; Anıl, Murat; Zengin, Neslihan; Can, Ender

    2016-01-01

    Laundry detergent pods (LDPs) are a new, concentrated form of detergent covered by a membrane of polyvinyl alcohol or other water-soluble material. In contrast to traditional laundry detergents, the spectrum of responses to exposure to LDPs ranges from mild to life-threatening events. This is a case report of a 3-year-old male who ingested part of an LDP, leading to a depressed level of consciousness, upper airway obstruction, and severe respiratory distress. The patient required intubation and mechanical ventilation for 2 days before being discharged. This rare, severe clinical pattern demonstrates the potential toxicity of these laundry detergents. In the literature, few cases that required intubation and ventilation have been reported. To our knowledge, this is also the first case of LDP exposure reported from Turkey.

  1. High frequency mechanical ventilation affects respiratory system mechanics differently in C57BL/6J and BALB/c adult mice.

    PubMed

    Hadden, Hélène

    2013-01-15

    We tested the hypothesis that high frequency ventilation affects respiratory system mechanical functions in C57BL/6J and BALB/c mice. We measured respiratory mechanics by the forced oscillation technique over 1h in anesthetized, intubated, ventilated BALB/c and C57BL/6J male mice. We did not detect any change in airway resistance, Rn, tissue damping, G, tissue elastance, H and hysteresivity, eta in BALB/c mice during 1h of ventilation at 150 or at 450 breaths/min; nor did we find a difference between BALB/c mice ventilated at 150 breaths/min compared with 450 breaths/min. Among C57BL/6J mice, except for H, all parameters remained unchanged over 1h of ventilation in mice ventilated at 150 breaths/min. However, after 10 and 30 min of ventilation at 450 breaths/min, Rn, and respiratory system compliance were lower, and eta was higher, than their starting value. We conclude that high frequency mechanical ventilation affects respiratory system mechanics differently in C57BL/6J and BALB/c adult mice.

  2. A closed-loop controller for mechanical ventilation of patients with ARDS.

    PubMed

    Anderson, Jeffrey R; East, Thomas D

    2002-01-01

    Mechanical ventilators are routinely used to care for patients who cannot adequately breath on their own. Management of mechanical ventilation often involves a careful watch of the patient's arterial blood-oxygen tension and requires frequent adjustment of ventilation parameters to optimize the therapy. This situation lends itself as a candidate for closed-loop control. This report describes a closed-loop control system based on well-established protocols to systematically maintain appropriate levels of positive end-expiratory pressure (PEEP) and inspired oxygen (FiO2) in patients with Adult Respiratory Distress Syndrome (ARDS). The closed-loop control system consists of an in-dwelling arterial oxygenation (PaO2) sensor (Pfizer Continucath), coupled to a Macintosh computer that continuously controls FiO2 and PEEP settings on a Hamilton Amadeus ventilator. The implemented protocols provide continuous closed-loop control of oxygenation and a balance between patient need and minimal therapy. The controller is based on a traditional proportional-integral-derivative (PID) approach. The idea is to control, or maintain, the patient's PaO2 level at a target value determined, or set, by the patient's physician. The controller also features non-linear and adaptive characteristics that allow the system to respond more aggressively to "threatening" levels of PaO2. Another benefit of the control system is the ability to display, monitor, record and store all system parameters, settings, and control variables for future analysis and study. The system was extensively tested in the laboratory and in animal trials prior to use on human subjects. The results of a small clinical trial indicated that the system maintained control of the patient's therapy nearly 84% of the time. During the remainder of this time, the controller was interrupted primarily for suctioning, PaO2 sensor calibration or replacement. The response of the closed-loop controller was found to be appropriate

  3. Comparison of pneumotachography and anemometery for flow measurement during mechanical ventilation with volatile anesthetics.

    PubMed

    Mondoñedo, Jarred R; Herrmann, Jacob; McNeil, John S; Kaczka, David W

    2016-11-14

    Volatile anesthetics alter the physical properties of inhaled gases, such as density and viscosity. We hypothesized that the use of these agents during mechanical ventilation would yield systematic biases in estimates of flow ([Formula: see text]) and tidal volume (V T) for two commonly used flowmeters: the pneumotachograph (PNT), which measures a differential pressure across a calibrated resistive element, and the hot-wire anemometer (HWA), which operates based on convective heat transfer from a current-carrying wire to a flowing gas. We measured [Formula: see text] during ventilation of a spring-loaded mechanical test lung, using both the PNT and HWA placed in series at the airway opening. Delivered V T was estimated from the numerically-integrated [Formula: see text]. Measurements were acquired under baseline conditions with room air, and during ventilation with increasing concentrations of isoflurane, sevoflurane, and desflurane. We also evaluated a simple compensation technique for HWA flow, which accounted for changes in gas mixture density. We found that discrepancies in estimated V T between the PNT and HWA occurred during ventilation with isoflurane (6.3 ± 3.0%), sevoflurane (10.0 ± 7.3%), and desflurane (25.8 ± 17.2%) compared to baseline conditions. The magnitude of these discrepancies increased with anesthetic concentration. A simple compensation factor based on density reduced observed differences between the flowmeters, regardless of the anesthetic or concentration. These data indicate that the choice and concentration of anesthetic agents are primary factors for differences in estimated V T between the PNT and HWA. Such discrepancies may be compensated by accounting for alterations in gas density.

  4. Influence of fluid and volume state on PaO2 oscillations in mechanically ventilated pigs.

    PubMed

    Bodenstein, Marc; Bierschock, Stephan; Boehme, Stefan; Wang, Hemei; Vogt, Andreas; Kwiecien, Robert; David, Matthias; Markstaller, Klaus

    2013-03-01

    Varying pulmonary shunt fractions during the respiratory cycle cause oxygen oscillations during mechanical ventilation. In artificially damaged lungs, cyclical recruitment of atelectasis is responsible for varying shunt according to published evidence. We introduce a complimentary hypothesis that cyclically varying shunt in healthy lungs is caused by cyclical redistribution of pulmonary perfusion. Administration of crystalloid or colloid infusions would decrease oxygen oscillations if our hypothesis was right. Therefore, n=14 mechanically ventilated healthy pigs were investigated in 2 groups: crystalloid (fluid) versus no-fluid administration. Additional volume interventions (colloid infusion, blood withdrawal) were carried out in each pig. Intra-aortal PaO2 oscillations were recorded using fluorescence quenching technique. Phase shift of oxygen oscillations during altered inspiratory to expiratory (I:E) ventilation ratio and electrical impedance tomography (EIT) served as control methods to exclude that recruitment of atelectasis is responsible for oxygen oscillations. In hypovolemia relevant oxygen oscillations could be recorded. Fluid and volume state changed PaO2 oscillations according to our hypothesis. Fluid administration led to a mean decline of 105.3 mmHg of the PaO2 oscillations amplitude (P<0.001). The difference of the amplitudes between colloid administration and blood withdrawal was 62.4 mmHg in pigs not having received fluids (P=0.0059). Fluid and volume state also changed the oscillation phase during altered I:E ratio. EIT excluded changes of regional ventilation (i.e., recruitment of atelectasis) to be responsible for these oscillations. In healthy pigs, cyclical redistribution of pulmonary perfusion can explain the size of respiratory-dependent PaO2 oscillations.

  5. Mechanical Ventilation

    MedlinePlus

    ... body ■ To help the lungs get rid of carbon dioxide ■ To ease the work of breathing—Some people ... rays and blood drawn to measure oxygen and carbon dioxide (“blood gases”). Members of the health care team ( ...

  6. Investigating the effects of strap tension during non-invasive ventilation mask application: a combined biomechanical and biomarker approach

    PubMed Central

    Worsley, Peter R; Prudden, George; Gower, George; Bader, Dan L

    2016-01-01

    Non-invasive ventilation is commonly used for respiratory support. However, in some cases, mask application can cause pressure ulcers to specific features of the face, resulting in pain and reduced quality of life for the individual. This study investigated the effects of mask strap tension on the biomechanical and biomarker responses at the skin interface. Healthy participants (n = 13) were recruited and assigned two different masks in a random order, which were fitted with three strap conditions representing increments of 5 mm to increase tension. Masks were worn for 10 minutes at each tension followed by a 10-minute refractory period. Assessment at the device–skin interface included measurements of pressures at the nose and cheeks, temperature and humidity, a selection of inflammatory cytokine concentrations collected from sebum and scores of comfort. The results indicated significantly higher interface pressures at the bridge of the nose compared to the cheeks for both masks (p < 0.05), with nasal interface pressures significantly increasing with elevated strap tension (p < 0.05). One inflammatory cytokine, IL-1α, increased following mask application at the highest tension, with median increases from baselines ranging from 21 to 33%. The other cytokines revealed a less consistent trend with strap tension. The participants reported statistically greater discomfort during elevated strap tension. Temperature and humidity values under the mask were elevated from ambient conditions, although no differences were observed between mask type or strap tension. The bony prominence on the bridge of the nose represented a vulnerable area of skin during respiratory mask application. This study has shown that mask strap tension has a significant effect on the pressure exerted on the nose. This can result in discomfort and an inflammatory response at the skin surface. Further studies are required to investigate respiratory mask application for appropriate individuals with

  7. Sulfide toxicity: Mechanical ventilation and hypotension determine survival rate and brain necrosis

    SciTech Connect

    Baldelli, R.J.; Green, F.H.Y.; Auer, R.N. )

    1993-09-01

    Occupational exposure to hydrogen sulfide is one of the leading causes of sudden death in the workplace, especially in the oil and gas industry. High-dose exposure causes immediate neurogenic apnea and death; lower doses cause [open quotes]knockdown[close quotes] (transient loss of consciousness, with apnea). Because permanent neurological sequelae have been reported, the authors sought to determine whether sulfide can directly kill central nervous system neurons. Ventilated and unventilated rats were studied to allow administration of higher doses of sulfide and to facilitate physiological monitoring. It was extremely difficult to produce cerebral necrosis with sulfide. Only one of eight surviving unventilated rats given high-dose sulfide (a dose that was lethal in [ge]50% of animals) showed cerebral necrosis. Mechanical ventilation shifted the dose that was lethal in 50% of the animals to 190 mg/kg from 94 mg/kg in the unventilated rats. Sulfide was found to potently depress blood pressure. Cerebral necrosis was absent in the ventilated rats (n = 11), except in one rat that showed profound and sustained hypotension to [le]35 Torr. Electroencephalogram activity ceased during exposure but recovered when the animals regained consciousness. The authors conclude that very-high-dose sulfide is incapable of producing cerebral necrosis by a direct histotoxic effect. 32 refs., 5 figs.

  8. Chest physiotherapy in mechanically ventilated patients without pneumonia—a narrative review

    PubMed Central

    De Regt, Jouke; Honoré, Patrick M.

    2017-01-01

    A beneficial adjuvant role of chest physiotherapy (CPT) to promote airway clearance, alveolar recruitment, and ventilation/perfusion matching in mechanically ventilated (MV) patients with pneumonia or relapsing lung atelectasis is commonly accepted. However, doubt prevails regarding the usefulness of applying routine CPT in MV subjects with no such lung diseases. In-depth narrative review based on a literature search for prospective randomized trials comparing CPT with a non-CPT strategy in adult patients ventilated for at least 48 h. Six relevant studies were identified. Sample size was small. Various CPT modalities were used including body positioning, manual chest manipulation (mobilization, percussion, vibration, and compression), and specific techniques such as lung hyperinflation and intrapulmonary percussion. Control subjects mostly received general nursing care and tracheal suction. In general, CPT was safe and supportive, yet had debatable or no significant impact on any relevant patient outcome parameter, including pneumonia. Current evidence does not support “prophylactic” CPT in adult MV patients without pneumonia. PMID:28203436

  9. Global survey on nebulization of antimicrobial agents in mechanically ventilated patients: a call for international guidelines.

    PubMed

    Solé-Lleonart, C; Roberts, J A; Chastre, J; Poulakou, G; Palmer, L B; Blot, S; Felton, T; Bassetti, M; Luyt, C-E; Pereira, J M; Riera, J; Welte, T; Qiu, H; Rouby, J-J; Rello, J

    2016-04-01

    Nebulized antimicrobial agents are increasingly administered for treatment of respiratory infections in mechanically ventilated (MV) patients. A structured online questionnaire assessing the indications, dosages and recent patterns of use for nebulized antimicrobial agents in MV patients was developed. The questionnaire was distributed worldwide and completed by 192 intensive care units. The most common indications for using nebulized antimicrobial agent were ventilator-associated tracheobronchitis (VAT; 58/87), ventilator-associated pneumonia (VAP; 56/87) and management of multidrug-resistant, Gram-negative (67/87) bacilli in the respiratory tract. The most common prescribed nebulized agents were colistin methanesulfonate and sulfate (36/87, 41.3% and 24/87, 27.5%), tobramycin (32/87, 36.7%) and amikacin (23/87, 26.4%). Colistin methanesulfonate, amikacin and tobramycin daily doses for VAP were significantly higher than for VAT (p < 0.05). Combination of parenteral and nebulized antibiotics occurred in 50 (86%) of 58 prescriptions for VAP and 36 (64.2%) of 56 of prescriptions for VAT. The use of nebulized antimicrobial agents in MV patients is common. There is marked heterogeneity in clinical practice, with significantly different in use between patients with VAP and VAT. Randomized controlled clinical trials and international guidance on indications, dosing and antibiotic combinations to improve clinical outcomes are urgently required.

  10. Setting mechanical ventilation in ARDS patients during VV-ECMO: where are we?

    PubMed

    Del Sorbo, L; Goffi, A; Goligher, E; Fan, E; Slutsky, A S

    2015-12-01

    Currently, many centers use venovenous extracorporeal membrane oxygenation (VV-ECMO) as an adjunctive means of gas exchange to mechanical ventilation (MV) in patients with severe ARDS and refractory hypoxemia. One of the most interesting and controversial issues in the management of these patients is how to set the ventilatory strategy. The support provided by VV-ECMO makes the balance between risks and benefits of MV remarkably different from the conventional setting, since the need for MV to facilitate oxygenation and carbon dioxide clearance is greatly reduced or abolished during VV-ECMO. Therefore, the risks of causing ventilator-induced lung injury are of foremost importance; however, the issue of the optimum ventilatory strategy during VV-ECMO has not received sufficient consideration. This paper will describe the diverse MV strategies applied during VV-ECMO in clinical practice and will highlight specific pathophysiological considerations that are crucial in the process of defining optimal ventilation settings in patients with ARDS supported with VV-ECMO.

  11. Infraclavicular axillary vein cannulation using ultrasound in a mechanically ventilated general intensive care population.

    PubMed

    Glen, H; Lang, I; Christie, L

    2015-09-01

    Central venous catheter (CVC) insertion is commonly undertaken in the ICU. The use of ultrasound (US) to facilitate CVC insertion is standard and is supported by guidelines. Because the subclavian vein cannot be insonated where it underlies the clavicle, its use as a CVC site is now less common. The axillary vein, however, can be seen on US just distal to the subclavian vein and placement of a CVC at this site gives a result which is functionally indistinguishable from a subclavian CVC. We evaluated placement of US-guided axillary CVCs in mechanically ventilated intensive care patients. Data were collected for 125 consecutive US-guided axillary CVC procedures in ventilated patients in an adult intensive care setting. All lines were inserted using real-time US guidance with an out-of-plane technique. One hundred and twenty-five procedures occurred in 119 patients. Successful line placement was achieved in 117 out of 125 (94%) procedures. Complications included four procedures that required repeating due to catheter malposition and one arterial puncture. The median number of attempts per procedure was one (IQR 1 to 2). Thirty-nine (31%) patients had a body mass index of 30 or above, 43 (34%) patients had a coagulopathy and 70 (56%) patients had significant ventilator dependence (FiO2 of 0.5 or above, or positive end expiratory pressure 10 cmH20 or above). The technique of US-guided axillary CVC access can be undertaken successfully in ventilated intensive care patients, even in challenging circumstances. Taken together with existing work on the utility and safety of this technique, we suggest that it be adopted more widely in the intensive care population.

  12. Role of tidal volume, FRC, and end-inspiratory volume in the development of pulmonary edema following mechanical ventilation.

    PubMed

    Dreyfuss, D; Saumon, G

    1993-11-01

    Mechanical ventilation with high peak inspiratory pressure and large tidal volume (VT) produces permeability pulmonary edema. Whether it is mean or peak inspiratory pressure (i.e., mean or end-inspiratory volume) that is the major determinant of ventilation-induced lung injury is unsettled. Rats were ventilated with increasing tidal volumes starting from different degrees of FRC that were set by increasing end-expiratory pressure during positive-pressure ventilation. Pulmonary edema was assessed by the measurement of extravascular lung water content. The importance of permeability alterations was evaluated by measurement of dry lung weight and determination of albumin distribution space. Pulmonary edema with permeability alterations occurred regardless of the value of positive end-expiratory pressure (PEEP), provided the increase in VT was large enough. Similarly, edema occurred even during normal VT ventilation provided the increase in PEEP was large enough. Furthermore, moderate increases in VT or PEEP that were innocuous when applied alone, produced edema when combined. The effect of PEEP was not the consequence of raised airway pressure but of the increase in FRC since similar observations were made in animals ventilated with negative inspiratory pressure. However, although permeability alterations were similar, edema was less marked in animals ventilated with PEEP than in those ventilated with zero end-expiratory pressure (ZEEP) with the same end-inspiratory pressure. This "beneficial" effect of PEEP was probably the consequence of hemodynamic alterations. Indeed, infusion of dopamine to correct the drop in systemic arterial pressure that occurred during PEEP ventilation resulted in a significant increase in pulmonary edema. In conclusion, rather than VT or FRC value, the end-inspiratory volume is probably the main determinant of ventilation-induced edema. Hemodynamic status plays an important role in modulating the amount of edema during lung overinflation

  13. Can routine oral care with antiseptics prevent ventilator-associated pneumonia in patients receiving mechanical ventilation? An update meta-analysis from 17 randomized controlled trials

    PubMed Central

    Li, Longti; Ai, Zhibing; Li, Longzhu; Zheng, Xuesong; Jie, Luo

    2015-01-01

    Background: Whether oral antiseptics could reduce the risk of ventilator associated pneumonia (VAP) in patients receiving mechanical ventilation remains controversial. We performed a meta-analysis to assess the effect of oral care with antiseptics on the prevalence of ventilator associated pneumonia in adult critically ill patients. Methods: A comprehensive search of PubMed, Embase and Web of Science were performed to identity relevant studies. Eligible studies were randomized controlled trials of mechanically ventilated adult patients receiving oral care with antiseptics. The quality of included studies was assessed by the Jadad score. Relative risks (RRs), weighted mean differences (WMDs), and 95% confidence intervals (CIs) were calculated and pooled using a fixed-effects model or random-effects model. Heterogeneity among the studies was assessed with I 2 test. Results: 17 studies with a total number of 4249 met the inclusion criteria. Of the 17 studies, 14 assessed the effect of chlorhexidine, and 3 investigated the effect of povidone-iodine. Overall, oral care with antiseptics significantly reduced the prevalence of VAP (RR=0.72, 95% CI: 0.57, 0.92; P=0.008). The use of chlorhexidine was shown to be effective (RR=0.73, 95% CI: 0.57, 0.93; P=0.012), whereas this effect was not observed in povidone-iodine (RR=0.51, 95% CI: 0.09, 2.82; P=0.438). Subgroup analyses showed that oral antiseptics were most marked in cardiac surgery patients (RR=0.54, 95% CI: 0.39, 0.74; P=0.00). Patients with oral antiseptics did not have a reduction in intensive care unit (ICU) mortality (RR=1.11, 95% CI: 0.95, 1.29; P=0.201), length of ICU stay (WMD=-0.10 days, 95% CI: -0.25, 0.05; P=0.188), or duration of mechanical ventilation (WMD=-0.05 days, 95% CI: -0.14, 0.04; P=0.260). Conclusion: Oral care with antiseptics significantly reduced the prevalence of VAP. Chlorhexidine application prevented the occurrence of VAP in mechanically ventilated patients but povidone-iodine did not

  14. [Comparison of volume preset and pressure preset ventilators during daytime nasal ventilation in chronic respiratory failure].

    PubMed

    Perrin, C; Wolter, P; Berthier, F; Tamisier, R; Jullien, V; Lemoigne, F; Blaive, B

    2001-02-01

    Both volume preset and pressure preset ventilators are available for domiciliary nasal ventilation. Owing to their technical characteristics, it has been suggested that impaired ventilatory mechanics might cause a drop in the tidal volume (Vt) delivered by pressure preset devices, thereby placing mechanical ventilation at risk of inefficacy. We have assessed two ventilator systems (one pressure preset and one volume preset) with regard to the tidal volume and end-tidal carbon dioxide tension (PetCO(2)) changes that may be achieved in a group of awake patients with stable chronic respiratory failure (CRF). Eleven patients with stable CRF were ventilated in the assist/control mode for two consecutive one-hour periods. One ventilator was tested each hour, in random order. The VIGIL'AIR(R) system was used to record Vt, Respiratory Rate (RR), and Inspiratory/Expiratory ratio (I/E). The deviation E (E=preset value - measured value) was calculated for each measurement. Changes in PetCO(2) and arterial oxygen saturation were determined respectively by a capnometer and a pulse oximeter. Comparison of the mean deviation of Vt calculated for the two ventilators revealed a difference in patients with chronic obstructive pulmonary disease (COPD). The deviation was greatest with the pressure preset ventilator (PPV), which gave mean measured values higher than the mean preset values. The same comparison failed to reveal any difference in restrictive CRF. Comparison of the volume preset and pressure preset ventilators for RR, I/E and PetCO(2) did not reveal any difference. Compared to the volume preset ventilator, the efficacy of PPV to ventilate is not affected by the restrictive or obstructive nature of CRF. Our results show that pressure-preset ventilator is an adequate alternative to the volume-preset device for daytime non invasive ventilation in chronic respiratory insufficiency.

  15. Mechanical ventilation and thoracic artificial lung assistance during mechanical circulatory support with PUCA pump: in silico study.

    PubMed

    De Lazzari, Claudio; Genuini, Igino; Quatember, Bernhard; Fedele, Francesco

    2014-02-01

    Patients assisted with left ventricular assist device (LVAD) may require prolonged mechanical ventilatory assistance secondary to postoperative respiratory failure. The goal of this work is the study of the interdependent effects LVAD like pulsatile catheter (PUCA) pump and mechanical ventilatory support or thoracic artificial lung (TAL), by the hemodynamic point of view, using a numerical simulator of the human cardiovascular system. In the simulator, different circulatory sections are described using lumped parameter models. Lumped parameter models have been designed to describe the hydrodynamic behavior of both PUCA pump and thoracic artificial lung. Ventricular behavior atrial and septum functions were reproduced using variable elastance model. Starting from simulated pathological conditions we studied the effects produced on some hemodynamic variables by simultaneous PUCA pump, thoracic artificial lung or mechanical ventilation assistance. Thoracic artificial lung was applied in parallel or in hybrid mode. The effects of mechanical ventilation have been simulated by changing mean intrathoracic pressure value from -4 mmHg to +5 mmHg. The hemodynamic variables observed during the simulations, in different assisted conditions, were: left and right ventricular end systolic (diastolic) volume, systolic/diastolic aortic pressure, mean pulmonary arterial pressure, left and right mean atrial pressure, mean systemic venous pressure and the total blood flow. Results show that the application of PUCA (without mechanical ventilatory assistance) increases the total blood flow, reduces the left ventricular end systolic volume and increases the diastolic aortic pressure. Parallel TAL assistance increases the right ventricular end diastolic (systolic) volume reduction both when PUCA is switched "ON" and both when PUCA is switched "OFF". By switching "OFF" the PUCA pump, it seems that parallel thoracic artificial lung assistance produces a greater cardiac output (respect to

  16. Inhibition of Nitro-Oxidative Stress Attenuates Pulmonary and Systemic Injury Induced by High-Tidal Volume Mechanical Ventilation.

    PubMed

    Martínez-Caro, Leticia; Nin, Nicolás; Sánchez-Rodríguez, Carolina; Ferruelo, Antonio; El Assar, Mariam; de Paula, Marta; Fernández-Segoviano, Pilar; Esteban, Andrés; Lorente, José A

    2015-07-01

    Mechanisms contributing to pulmonary and systemic injury induced by high tidal volume (VT) mechanical ventilation are not well known. We tested the hypothesis that increased peroxynitrite formation is involved in organ injury and dysfunction induced by mechanical ventilation. Male Sprague-Dawley rats were subject to low- (VT, 9 mL/kg; positive end-expiratory pressure, 5 cmH2O) or high- (VT, 25 mL/kg; positive end-expiratory pressure, 0 cmH2O) VT mechanical ventilation for 120 min, and received 1 of 3 treatments: 3-aminobenzamide (3-AB, 10 mg/kg, intravenous, a poly adenosine diphosphate ribose polymerase [PARP] inhibitor), or the metalloporphyrin manganese(III) tetrakis(1-methyl-4-pyridyl)porphyrin (MnTMPyP, 5 mg/kg intravenous, a peroxynitrite scavenger), or no treatment (control group), 30 min before starting the mechanical ventilation protocol (n = 8 per group, 6 treatment groups). We measured mean arterial pressure, peak inspiratory airway pressure, blood chemistry, and gas exchange. Oxidation (fluorescence for oxidized dihydroethidium), protein nitration (immunofluorescence and Western blot for 3-nitrotyrosine), PARP protein (Western blot) and gene expression of the nitric oxide (NO) synthase (NOS) isoforms (quantitative real-time reverse transcription polymerase chain reaction) were measured in lung and vascular tissue. Lung injury was quantified by light microscopy. High-VT mechanical ventilation was associated with hypotension, increased peak inspiratory airway pressure, worsened oxygenation; oxidation and protein nitration in lung and aortic tissue; increased PARP protein in lung; up-regulation of NOS isoforms in lung tissue; signs of diffuse alveolar damage at histological examination. Treatment with 3AB or MnTMPyP attenuated the high-VT mechanical ventilation-induced changes in pulmonary and cardiovascular function; down-regulated the expression of NOS1, NOS2, and NOS3; decreased oxidation and nitration in lung and aortic tissue; and attenuated

  17. Association Between Noninvasive Ventilation and Mortality Among Older Patients With Pneumonia

    PubMed Central

    Valley, Thomas S.; Walkey, Allan J.; Lindenauer, Peter K.; Wiener, Renda Soylemez; Cooke, Colin R.

    2016-01-01

    Objective Despite increasing use, evidence is mixed as to the appropriate use of noninvasive ventilation in patients with pneumonia. We aimed to determine the relationship between receipt of noninvasive ventilation and outcomes for patients with pneumonia in a real-world setting. Design, Setting, Patients We performed a retrospective cohort study of Medicare beneficiaries (aged > 64 yr) admitted to 2,757 acute-care hospitals in the United States with pneumonia, who received mechanical ventilation from 2010 to 2011. Exposures Noninvasive ventilation versus invasive mechanical ventilation. Measurement and Main Results The primary outcome was 30-day mortality with Medicare reimbursement as a secondary outcome. To account for unmeasured confounding associated with noninvasive ventilation use, an instrumental variable was used—the differential distance to a high noninvasive ventilation use hospital. All models were adjusted for patient and hospital characteristics to account for measured differences between groups. Among 65,747 Medicare beneficiaries with pneumonia who required mechanical ventilation, 12,480 (19%) received noninvasive ventilation. Patients receiving noninvasive ventilation were more likely to be older, male, white, rural-dwelling, have fewer comorbidities, and were less likely to be acutely ill as measured by organ failures. Results of the instrumental variable analysis suggested that, among marginal patients, receipt of noninvasive ventilation was not significantly associated with differences in 30-day mortality when compared with invasive mechanical ventilation (54% vs 55%; p = 0.92; 95% CI of absolute difference, –13.8 to 12.4) but was associated with significantly lower Medicare spending ($18,433 vs $27,051; p = 0.02). Conclusions Among Medicare beneficiaries hospitalized with pneumonia who received mechanical ventilation, noninvasive ventilation use was not associated with a real-world mortality benefit. Given the wide CIs, however, substantial

  18. Stable Small Animal Mechanical Ventilation for Dynamic Lung Imaging to Support Computational Fluid Dynamics Models

    SciTech Connect

    Jacob, Rick E.; Lamm, W. J.

    2011-11-08

    Pulmonary computational fluid dynamics models require 3D images to be acquired over multiple points in the dynamic breathing cycle, with no breath holds or changes in ventilatory mechanics. With small animals, these requirements result in long imaging times ({approx}90 minutes), over which lung mechanics, such as compliance, can gradually change if not carefully monitored and controlled. These changes, caused by derecruitment of parenchymal tissue, are manifested as an upward drift in peak inspiratory pressure or by changes in the pressure waveform and/or lung volume over the course of the experiment. We demonstrate highly repeatable mechanical ventilation in anesthetized rats over a long duration for pulmonary CT imaging throughout the dynamic breathing cycle. We describe significant updates to a basic commercial ventilator that was acquired for these experiments. Key to achieving consistent results was the implementation of periodic deep breaths, or sighs, of extended duration to maintain lung recruitment. In addition, continuous monitoring of breath-to-breath pressure and volume waveforms and long-term trends in peak inspiratory pressure and flow provide diagnostics of changes in breathing mechanics.

  19. Shortening the length of stay and mechanical ventilation time by using positive suggestions via MP3 players for ventilated patients.

    PubMed

    K Szilágyi, Adrienn; Diószeghy, Csaba; Fritúz, Gábor; Gál, János; Varga, Katalin

    2014-03-01

    Long stay in intensive care unit (ICU) and prolonged ventilation are deleterious for subsequent quality of life and surcharge financial capacity. We have already demonstrated the beneficial effects of using suggestive communication on recovery time during intensive care. The aim of our present study was to prove the same effects with standardized positive suggestive message delivered by an MP3 player. Patients ventilated in ICU were randomized into a control group receiving standard ICU treatment and two groups with a standardized pre-recorded material delivered via headphones: a suggestive message about safety, self-control, and recovery for the study group and a relaxing music for the music group. Groups were similar in terms of age, gender, and mortality, but the SAPS II scores were higher in the study group than that in the controls (57.8 ± 23.6 vs. 30.1 ± 15.5 and 33.7 ± 17.4). Our post-hoc analysis results showed that the length of ICU stay (134.2 ± 73.3 vs. 314.2 ± 178.4 h) and the time spent on ventilator (85.2 ± 34.9 vs. 232.0 ± 165.6 h) were significantly shorter in the study group compared to the unified control. The advantage of the structured positive suggestive message was proven against both music and control groups.

  20. Mechanisms of aquatic species invasions across the SALCC - an update

    USGS Publications Warehouse

    Benson, Amy J.

    2014-01-01

    Our project represents the first attempt to utilize the NAS Database within the context of a Landscape Conservation Cooperative conservation blueprint. A significant amount of effort during the past year was dedicated to determining the most appropriate use of these data for the purposes of identifying the mechanisms and patterns of aquatic species invasions. Descriptive analyses were first undertaken to characterize the spatial and temporal characteristics of the SALCC subset of NAS data.

  1. Early and small changes in serum creatinine concentrations are associated with mortality in mechanically ventilated patients.

    PubMed

    Nin, Nicolás; Lombardi, Raúl; Frutos-Vivar, Fernando; Esteban, Andrés; Lorente, José A; Ferguson, Niall D; Hurtado, Javier; Apezteguia, Carlos; Brochard, Laurent; Schortgen, Fréderique; Raymondos, Konstantinos; Tomicic, Vinko; Soto, Luis; González, Marco; Nightingale, Peter; Abroug, Fekri; Pelosi, Paolo; Arabi, Yaseen; Moreno, Rui; Anzueto, Antonio

    2010-08-01

    Emerging evidence suggests that minor changes in serum creatinine concentrations are associated with increased hospital mortality rates. However, whether serum creatinine concentration (SCr) on admission and its change are associated with an increased mortality rate in mechanically ventilated patients is not known. We have conducted an international, prospective, observational cohort study enrolling adult intensive care unit patients under mechanical ventilation (MV). Recursive partitioning was used to determine the values of SCr at the start of MV (SCr0) and the change in SCr ([DeltaSCr] defined as the maximal difference between the value at start of MV [day 0] and the value on MV day 2 at 8:00 am) that best discriminate mortality. In-hospital mortality, adjusted by a proportional hazards model, was the primary outcome variable. A total of 2,807 patients were included; median age was 59 years and median Simplified Acute Physiology Score II was 44. All-cause in-hospital mortality was 44%. The variable that best discriminated outcome was a SCr0 greater than 1.40 mg/dL (mortality, 57% vs. 36% for patients with SCr0 mechanically ventilated patients.

  2. Effects of thoracic squeezing on airway secretion removal in mechanically ventilated patients

    PubMed Central

    Yousefnia-Darzi, Farkhondeh; Hasavari, Farideh; Khaleghdoost, Tahereh; Kazemnezhad-Leyli, Ehsan; Khalili, Malahat

    2016-01-01

    Background: Accumulation of secretions in the airways of patients with an endotracheal tube and mechanical ventilation will have serious consequences. One of the most common methods of airway clearance is endotracheal suctioning. In order to facilitate discharge of airway secretion resulting in promotion of gas exchange, chest physiotherapy techniques can be used at the time of expiration before suction. Materials and Methods: In this clinical trial with a cross-over design, 50 mechanically ventilated patients admitted to intensive care units (ICUs) were randomly divided into two groups of thoracic squeezing. In each patient, two interventions of endotracheal suctioning were conducted, one with and the other without thoracic squeezing during exhalation, with a 3 h gap between the two interventions and an elapse of three respiratory cycles between the number of compressions. Sputum secreted was collected in a container connected to a suction catheter and weighed. Data were recorded in data gathering forms and analyzed using descriptive and inferential statistics (Wilcoxon and independent t-test, Chi-square) in SPSS version 16. Results: Findings showed that the mean weight of the suction secretions removed from airway without thoracic squeezing was 1.35 g and that of suction secretions removed by thoracic squeezing was 1.94 g. Wilcoxon test showed a significant difference regarding the rate of secretion between the two techniques (P = 0.003). Conclusions: According to the study findings, endotracheal suction with thoracic squeezing on expiration helps airway secretion discharge more than suction alone in patients on mechanical ventilators and can be used as an effective method. PMID:27186214

  3. Placebo-controlled trial of midazolam sedation in mechanically ventilated newborn babies.

    PubMed

    Jacqz-Aigrain, E; Daoud, P; Burtin, P; Desplanques, L; Beaufils, F

    1994-09-03

    Although midazolam is used for sedation of mechanically ventilated newborn babies, this treatment has not been evaluated in a randomised trial. We have done a prospective placebo-controlled study of the effects of midazolam on haemodynamic variables and sedation as judged by a five-item behaviour score. 46 newborn babies on mechanical ventilation for respiratory distress syndrome were randomly assigned to receive midazolam (n = 24) or placebo (n = 22) as a continuous infusion. Doses of midazolam were calculated to obtain plasma concentrations between 200 and 1000 ng/mL within 24 h of starting treatment and to maintain these values throughout the study. Haemodynamic and ventilatory variables were noted every hour, as were complications and possible side-effects of treatment. Mean (SD) duration of inclusion was 78.7 (30.9) h. 1 patient in the treatment group and 7 in the placebo group were withdrawn because of inadequate sedation (p < 0.05). Midazolam gave a significantly better sedative effect than placebo, as estimated by the behaviour score (p < 0.05). Heart rate and blood pressure were reduced by treatment but remained within the normal range for gestational age and there was no effect on ventilatory indices. The incidence of complications was similar in the two groups. No midazolam-related side-effects were noted. Continuous infusion of midazolam at doses adapted to gestational age induces effective sedation in newborn babies on mechanical ventilation, with positive effects on haemodynamic variables. The course of the respiratory distress syndrome was not influenced by this treatment. Midazolam was given over only a few days and the limited effects on heart rate and blood pressure that we report should not encourage long-term administration.

  4. Complications in mechanically ventilated patients of Guillain–Barre syndrome and their prognostic value

    PubMed Central

    Netto, Archana Becket; Taly, Arun B.; Kulkarni, Girish B.; Uma Maheshwara Rao, G. S.; Rao, Shivaji

    2017-01-01

    Introduction: The spectrum of various complications in critically ill Guillain–Barre syndrome (GBS) and its effect on the prognosis is lacking in literature. This study aimed at enumerating the complications in such a cohort and their significance in the prognosis and mortality. Materials and Methods: Retrospective case record analysis of all consecutive mechanically ventilated patients of GBS in neurology Intensive Care Unit (ICU) of a tertiary care institute for 10 years was done. Demographic, laboratory, and treatment details and outcome parameters were recorded. Results: Among the 173 patients were 118 men and 55 women (2.1:1), aged 1–84 years. The average number of ICU complications per patient was 6.8 ± 1.8 (median = 7, range = 1–12). The most common complication was tracheobronchitis (128). Other pulmonary complications were found in 36 patients. The next was metabolic hyponatremia (115) hypokalemia (67), hypocalcemia (13), stress hyperglycemia (10), hyperkalemia (8), hypernatremia (9). Sepsis (40), UTI (47), dysautonomia (27), hypoalbuminemia (76), anemia (75), seizures (8), paralytic ileus (5), bleeding (4), anoxic encephalopathy (3), organ failures (12), deep vein thrombosis (7), and drug rashes (1) were also noted. The complications, considered significant in causing death, Hughes scale ≤ 3 at discharge, prolonged mechanical ventilation (>21 days) and hospitalization (>36 days) were pneumonia, hyponatremia, hypokalemia, urinary infection, tracheobronchial infections, hypoalbuminemia, sepsis, anemia dysautonomia. Conclusion: Active monitoring and appropriate and early intervention by the clinician will improve the quality of life of these patients and reduce the cost of prolonged mechanical ventilation and ICU stay. PMID:28149085

  5. Entropy correlates with Richmond Agitation Sedation Scale in mechanically ventilated critically ill patients.

    PubMed

    Sharma, Ankur; Singh, Preet Mohinder; Trikha, Anjan; Rewari, Vimi; Chandralekha

    2014-04-01

    Sedation is routinely used in intensive care units. However due to absence of objective scoring systems like Bispectral Index and entropy our ability to regulate the degree of sedation is limited. This deficiency is further highlighted by the fact that agitation scores used in intensive care units (ICU) have no role in paralyzed patients. The present study compares entropy as a sedation scoring modality with Richmond Agitation Sedation Scale (RASS) in mechanically ventilated, critically ill patients in an ICU. Twenty-seven, mechanically ventilated, critically ill patients of either sex, 16-65 years of age, were studied over a period of 24 h. They received a standard sedation regimen consisting of a bolus dose of propofol 0.5 mg/kg and fentanyl 1 lg/kg followed by infusions of propofol and fentanyl ranging from 1.5 to 5 mg/kg/h and 0.5 to 2.0 lg/kg/h, respectively. Clinically relevant values of RASS for optimal ICU sedation (between 0 and -3) in non-paralyzed patients were compared to corresponding entropy values, to find if any significant correlation exists between the two. These entropy measurements were obtained using the Datex-Ohmeda-M-EntropyTM module. This module is presently not approved by Food and Drug Administration (FDA) for monitoring sedation in ICU. A total of 527 readings were obtained. There was a statistically significant correlation between the state entropy (SE) and RASS [Spearman's rho/rs = 0.334, p\\0.0001]; response entropy (RE) and RASS [Spearman's rho/rs = 0.341, p\\0.0001]). For adequate sedation as judged by a RASS value of 0 to -3, the mean SE was 57.86 ± 16.50 and RE was 67.75 ± 15.65. The present study illustrates that entropy correlates with RASS (between scores 0 and -3) when assessing the level of sedation in mechanically ventilated critically ill patients.

  6. Validity and reliability of “Persian Weaning Tool” in mechanically ventilated patients

    PubMed Central

    Bazrafshan, Fatemeh; Irajpour, Alireza; Abbasi, Saeed; Mahaki, Behzad

    2016-01-01

    Background: “Persian Weaning Tool” (PWT) is the only specific, national protocol designed to assess patients’ readiness for weaning from mechanical ventilation in Iran. This study was developed to determine the validity and reliability of this protocol. Materials and Methods: This is a psychometric study conducted on 31 patients connected to mechanical ventilation were ready from weaning according to anesthesiologist's diagnosis and was selected through convenient sampling. The patients selected from Intensive Care Units (ICUs) of Al-Zahra Hospital in Isfahan. The sheet data collection includes demographic data, PWT; Burn's Wean Assessment Program (BWAP), and Morganroth's scale. To determine the inter-rater reliability between researcher and his partner, Pearson correlation and paired t-test were used. To assess the criterion validity of the PWT in relation to Burn's and Morganroth's weaning scales (as criteria), Pearson correlation and McNemar tests were used. To specify a minimum acceptable score of the PWT for weaning from mechanical ventilation, receiver operating characteristic curve was used. Results: The results showed that there was statistically significant correlation between score of PWT and BWAP (r = 0.370 with P < 0.05) and there were no statistically significant differences between these tools in terms of identification of patients’ readiness for weaning (P = 0.453). There was statistically significant correlation between PWT score obtained by researcher and his colleague (r = 0.928), and the reliability of this tool was approved. The PWTs cut of point was calculated as 57 (sensitivity = 0.679, specificity = 1). Conclusions: The reliability and validity of the PWT were confirmed for this study's sample size. Consequently, the findings of this study can be used to measure the PWTs effectiveness and applicability in ICUs. PMID:27761432

  7. Measurement of lung function using Electrical Impedance Tomography (EIT) during mechanical ventilation

    NASA Astrophysics Data System (ADS)

    Nebuya, Satoru; Koike, Tomotaka; Imai, Hiroshi; Noshiro, Makoto; Brown, Brian H.; Soma, Kazui

    2010-04-01

    The consistency of regional lung density measurements as estimated by Electrical Impedance Tomography (EIT), in eleven patients supported by a mechanical ventilator, was validated to verify the feasibility of its use in intensive care medicine. There were significant differences in regional lung densities between the normal lung and diseased lungs associated with pneumonia, atelectasis and pleural effusion (Steel-Dwass test, p < 0.05). Temporal changes in regional lung density of patients with atelectasis were observed to be in good agreement with the results of clinical diagnosis. These results indicate that it is feasible to obtain a quantitative value for regional lung density using EIT.

  8. [Parameters of controlled mechanical lung ventilation and external respiratory function during thoracoscopic surgeries in children of different age groups].

    PubMed

    Ovcharenko, N M; Tsypin, L E; Geodakian, O S; Demakhin, A A

    2011-01-01

    The purpose of the study is to estimate the parameters of mechanical ventilation and respiratory function during videotorachoscopic surgeries in children. 73 anesthesias were conducted in children aged 5 to 16 years of age. During the study, a detailed monitoring of respiratory function and parameters of mechanical ventilation was carried out. Indicators reflecting the lung function remained stable in all phases of the study. Parameters of mechanical ventilation during the study varied. Changes in PIP and MAP were similar in all age groups. The maximum changes of compliance were in the third group. One-lung ventilation is safe under certain conditions: increasing FiO2 from 0.5 to 1, the reduction of tidal volume up to 5-5.3 ml/kg, the use of a size or a half size smaller cuffed endotracheal tubes for intubation of the right and left main bronchus compared to those for tracheal intubation. For the intubation of the right main bronchus the endotracheal tube with the Murphy eye should be used, for the means ventilation of the upper lobe of the right lung. If the minute volume of breathing is adequate and there is no preoperative hypercapnia, the elimination of CO2 for one-lung ventilation is not disrupted and the tension of CO2 in arterial blood increases.

  9. Effects of Physician-Targeted Pay-for-Performance on Use of Spontaneous Breathing Trials in Mechanically Ventilated Patients.

    PubMed

    Barbash, Ian J; Pike, Francis; Gunn, Scott R; Seymour, Christopher W; Kahn, Jeremy M

    2016-12-12

    Rationale Pay-for-performance is an increasingly common quality improvement strategy despite the absence of robust supporting evidence. Objectives To determine the impact of a financial incentive program rewarding physicians for the completion of daily spontaneous breathing trials (SBTs) in three academic hospitals. Methods We compared data from mechanically ventilated patients from six months before to two years after introduction of a financial incentive program that provided annual payments to critical care physicians contingent on unit-level SBT completion rates. We used Poisson regression to compare the frequency of days on which SBTs were completed among eligible patients and days on which patients were excluded from SBT eligibility among all mechanically ventilated patients. We used multivariate regression to compare risk-adjusted duration of mechanical ventilation and in-hospital mortality. Measurements and Main Results The cohort included 7,291 mechanically ventilated patients with 75,621 ventilator days. Baseline daily SBT rates were 96.8% (Hospital A), 16.4% (Hospital B), and 74.7% (Hospital C). In hospital A, with the best baseline performance, there was no change in SBT rates, exclusion rates, or duration of mechanical ventilation across time periods. In hospitals B and C, with lower SBT completion rates at baseline, there was an increase in daily SBT completion rates and a concomitant increase in exclusions from eligibility. Duration of mechanical ventilation decreased in hospital C but not hospital B. Mortality was unchanged for all hospitals. Conclusions In hospitals with low baseline SBT completion, physician-targeted financial incentives were associated with increased SBT rates driven in part by increased exclusion rates, without consistent improvements in outcome.

  10. Ultrafine and Fine Particulate Matter Inside and Outside of Mechanically Ventilated Buildings

    PubMed Central

    Miller, Shelly L.; Facciola, Nick A.; Toohey, Darin; Zhai, John

    2017-01-01

    The objectives of this study were to measure levels of particulate matter (PM) in mechanically ventilated buildings and to improve understanding of filtration requirements to reduce exposure. With the use of an Ultra High Sensitivity Aerosol Spectrometer and an Aerodyne Mass Spectrometer, ultrafine (0.055–0.1 μm) and fine (0.1–0.7 μm) indoor and outdoor PM was measured as a function of time in an office, a university building, and two elementary schools. Indoor particle levels were highly correlated with outdoor levels. Indoor and outdoor number concentrations in Denver were higher than those in Boulder, with the highest number concentrations occurring during summer and fall. The ratio of indoor-to-outdoor (I/O) PM was weakly but positively correlated with the amount of ventilation provided to the indoor environment, did not vary much with particle size (ranged between 0.48 and 0.63 for the entire size range), and was similar for each period of the week (weekend vs. weekday, night vs. day). Regression analyses showed that ultrafine indoor PM baseline concentrations were higher at night from nighttime infiltration. A lag time was observed between outdoor and indoor measurements. Weekday days had the shortest lag time of 11 min, and weekend nighttime lags when the HVAC was not in use were 50 to 148 min. Indoor-outdoor PM concentration plots showed ultrafine PM was more correlated compared to fine, and especially when the HVAC system was on. Finally, AMS data showed that most of the PM was organic, with occasional nitrate events occurring outdoors. During nitrate events, there were less indoor particles detected, indicating a loss of particulate phase nitrate. The results from this study show that improved filtration is warranted in mechanically ventilated buildings, particularly for ultrafine particles, and that nighttime infiltration is significant depending on the building design. PMID:28134841

  11. Ultrafine and Fine Particulate Matter Inside and Outside of Mechanically Ventilated Buildings.

    PubMed

    Miller, Shelly L; Facciola, Nick A; Toohey, Darin; Zhai, John

    2017-01-28

    The objectives of this study were to measure levels of particulate matter (PM) in mechanically ventilated buildings and to improve understanding of filtration requirements to reduce exposure. With the use of an Ultra High Sensitivity Aerosol Spectrometer and an Aerodyne Mass Spectrometer, ultrafine (0.055-0.1 μm) and fine (0.1-0.7 μm) indoor and outdoor PM was measured as a function of time in an office, a university building, and two elementary schools. Indoor particle levels were highly correlated with outdoor levels. Indoor and outdoor number concentrations in Denver were higher than those in Boulder, with the highest number concentrations occurring during summer and fall. The ratio of indoor-to-outdoor (I/O) PM was weakly but positively correlated with the amount of ventilation provided to the indoor environment, did not vary much with particle size (ranged between 0.48 and 0.63 for the entire size range), and was similar for each period of the week (weekend vs. weekday, night vs. day). Regression analyses showed that ultrafine indoor PM baseline concentrations were higher at night from nighttime infiltration. A lag time was observed between outdoor and indoor measurements. Weekday days had the shortest lag time of 11 min, and weekend nighttime lags when the HVAC was not in use were 50 to 148 min. Indoor-outdoor PM concentration plots showed ultrafine PM was more correlated compared to fine, and especially when the HVAC system was on. Finally, AMS data showed that most of the PM was organic, with occasional nitrate events occurring outdoors. During nitrate events, there were less indoor particles detected, indicating a loss of particulate phase nitrate. The results from this study show that improved filtration is warranted in mechanically ventilated buildings, particularly for ultrafine particles, and that nighttime infiltration is significant depending on the building design.

  12. Mechanism of Reduced Lung Injury by High Frequency Nasal Ventilation in a Preterm Lamb Model of Neonatal Chronic Lung Disease

    PubMed Central

    Rehan, Virender K.; Fong, Jeanette; Lee, Robert; Sakurai, Reiko; Wang, Zheng-Ming; Dahl, Mar Janna; Lane, Robert H.; Albertine, Kurt H.; Torday, John S.

    2011-01-01

    The mechanism underlying the potentially beneficial effects of the “gentler” modes of ventilation on chronic lung disease (CLD) of the premature infant is not known. We have previously demonstrated that alveolar Parathyroid Hormone-related Protein-Peroxisome Proliferator-Activated Receptorγ (PTHrP-PPARγ) signaling is critically important in alveolar formation, and this signaling pathway is disrupted in hyperoxia- and/or volutrauma-induced neonatal rat lung injury. Whether the same paradigm is also applicable to CLD, resulting from prolonged intermittent mandatory ventilation (IMV), and whether differential effects of the mode of ventilation on the PTHrP-PPARγ signaling pathway explain the potential benefits of the “gentler” modes of ventilation are not known. Using a well-established preterm lamb model of neonatal CLD, we tested the hypothesis that ventilatory support using high-frequency nasal ventilation (HFNV) promotes alveolar PTHrP-PPARγ signaling, whereas IMV inhibits it. Preterm lambs managed by HFNV or IMV for 21 days following preterm delivery at 132-day gestation were studied by Western hybridization and immunofluorescence labeling for key markers of alveolar homeostasis and injury/repair. In lambs managed by IMV, the abundance of key homeostatic alveolar epithelial-mesenchymal markers was reduced, whereas it was significantly increased in the HFNV group, providing a potential molecular mechanism by which “gentler” modes of ventilation reduce neonatal CLD. PMID:21814155

  13. A study on reliability and validity of the Turkish version of the Face Anxiety Scale on mechanically-ventilated patients.

    PubMed

    Iyigun, Emine; Pazar, Berrin; Tastan, Sevinc

    2016-12-01

    Mechanical ventilation treatment causes patient anxiety, such that for those people dependent on mechanical ventilation, it was suggested to self-evaluate anxiety levels using a scale. The aim of this study was to assess the reliability and validity of the Turkish version of the Face Anxiety Scale in order to evaluate general patient anxiety levels for those receiving mechanical ventilation in a cardiovascular surgery (CVS) intensive care unit (ICU). A survey was conducted between April and December 2015 with 99 patients in receipt of mechanical ventilation at the CVS-ICU of a military training hospital in Turkey. Patients' average age was 59.31±16.47 years (range 18-83 years), with 73.7% for males and 73.7% for those undergoing coronary artery bypass graft surgery. The average scores from the Face Anxiety Scale were 2.8±1.3. A statistically significant (positive) correlation was found between scores from the test and retest (r=0.87, p<0.001), which indicated that the scale was reliable. The relationship between the Face Anxiety Scale and Profile of the Mood States (POMS) of participants scored 0.89, corroborating the validity of the former (p<0.001). This study found that it was valuable for evaluating patient anxiety in those receiving mechanical ventilation.

  14. Sedation of mechanically ventilated adults in intensive care unit: a network meta-analysis

    PubMed Central

    Zhang, Zhongheng; Chen, Kun; Ni, Hongying; Zhang, Xiaoling; Fan, Haozhe

    2017-01-01

    Sedatives are commonly used for mechanically ventilated patients in intensive care units (ICU). However, a variety of sedatives are available and their efficacy and safety have been compared in numerous trials with inconsistent results. To resolve uncertainties regarding usefulness of these sedatives, we performed a systematic review and network meta-analysis. Randomized controlled trials comparing sedatives in mechanically ventilated ICU patients were included. Graph-theoretical methods were employed for network meta-analysis. A total of 51 citations comprising 52 RCTs were included in our analysis. Dexmedetomidine showed shorter MV duration than lorazepam (mean difference (MD): 68.7; 95% CI: 18.2–119.3 hours), midazolam (MD: 10.2; 95% CI: 7.7–12.7 hours) and propofol (MD: 3.4; 95% CI: 0.9–5.9 hours). Compared with dexmedetomidine, midazolam was associated with significantly increased risk of delirium (OR: 2.47; 95% CI: 1.17–5.19). Our study shows that dexmedetomidine has potential benefits in reducing duration of MV and lowering the risk of delirium. PMID:28322337

  15. Mechanical Ventilation Induces an Inflammatory Response in Preinjured Lungs in Late Phase of Sepsis.

    PubMed

    Xuan, Wei; Zhou, Quanjun; Yao, Shanglong; Deng, Qingzhu; Wang, Tingting; Wu, Qingping

    2015-01-01

    Mechanical ventilation (MV) may amplify the lung-specific inflammatory response in preinjured lungs by elevating cytokine release and augmenting damage to the alveolar integrity. In this study, we test the hypothesis that MV exerts different negative impacts on inflammatory response at different time points of postlung injury. Basic lung injury was induced by cecal ligation and puncture (CLP) surgery in rats. Physiological indexes including blood gases were monitored during MV and samples were assessed following each experiment. Low V T (tidal volume) MV caused a slight increase in cytokine release and tissue damage at day 1 and day 4 after sepsis induced lung injury, while cytokine release from the lungs in the two moderately ventilated V T groups was amplified. Interestingly, in the two groups where rats received low V T MV, we found that infiltration of inflammatory cells was only profound at day 4 after CLP. Marked elevation of protein leakage indicated a compromise in alveolar integrity in rats that received moderate V T MV at day 4 following CLP, correlating with architectural damage to the alveoli. Our study indicates that preinjured lungs are more sensitive to mechanical MV at later phases of sepsis, and this situation may be a result of differing immune status.

  16. System identification and closed-loop control of end-tidal CO2 in mechanically ventilated patients.

    PubMed

    Hahn, Jin-Oh; Dumont, Guy A; Anersmino, J Mark

    2012-11-01

    This paper presents a systematic approach to system identification and closed-loop control of end-tidal carbon dioxide partial pressure (PETCO2) in mechanically ventilated patients. An empirical model consisting of a linear dynamic system followed by an affine transform is proposed to derive a low-order and high-fidelity representation that can reproduce the positive and inversely proportional dynamic input-output relationship between PETCO2 and minute ventilation (MV) in mechanically ventilated patients. The predictive capability of the empirical model was evaluated using experimental respiratory data collected from eighteen mechanically ventilated human subjects. The model predicted PETCO2 response accurately with a root-mean-squared error (RMSE) of 0.22+/-0.16 mmHg and a coefficient of determination (r2) of 0.81+/-0.18 (mean+/-SD) when a second-order rational transfer function was used as its linear dynamic component. Using the proposed model, a closedloop control method for PETCO2 based on a proportionalintegral (PI) compensator was proposed by systematic analysis of the system root locus. For the eighteen mechanically ventilated patient models identified, the PI compensator exhibited acceptable closed-loop response with a settling time of 1.27+/- 0.20 min and a negligible overshoot (0.51+/-1.17%), in addition to zero steady-state PETCO2 set point tracking. The physiologic implication of the proposed empirical model was analyzed by comparing it with the traditional multi-compartmental model widely used in pharmacological modeling.

  17. Time course analysis of mechanical ventilation-induced diaphragm contractile muscle dysfunction in the rat.

    PubMed

    Corpeno, R; Dworkin, B; Cacciani, N; Salah, H; Bergman, H-M; Ravara, B; Vitadello, M; Gorza, L; Gustafson, A-M; Hedström, Y; Petersson, J; Feng, H-Z; Jin, J-P; Iwamoto, H; Yagi, N; Artemenko, K; Bergquist, J; Larsson, L

    2014-09-01

    Controlled mechanical ventilation (CMV) plays a key role in triggering the impaired diaphragm muscle function and the concomitant delayed weaning from the respirator in critically ill intensive care unit (ICU) patients. To date, experimental and clinical studies have primarily focused on early effects on the diaphragm by CMV, or at specific time points. To improve our understanding of the mechanisms underlying the impaired diaphragm muscle function in response to mechanical ventilation, we have performed time-resolved analyses between 6 h and 14 days using an experimental rat ICU model allowing detailed studies of the diaphragm in response to long-term CMV. A rapid and early decline in maximum muscle fibre force and preceding muscle fibre atrophy was observed in the diaphragm in response to CMV, resulting in an 85% reduction in residual diaphragm fibre function after 9-14 days of CMV. A modest loss of contractile proteins was observed and linked to an early activation of the ubiquitin proteasome pathway, myosin:actin ratios were not affected and the transcriptional regulation of myosin isoforms did not show any dramatic changes during the observation period. Furthermore, small angle X-ray diffraction analyses demonstrate that myosin can bind to actin in an ATP-dependent manner even after 9-14 days of exposure to CMV. Thus, quantitative changes in muscle fibre size and contractile proteins are not the dominating factors underlying the dramatic decline in diaphragm muscle function in response to CMV, in contrast to earlier observations in limb muscles. The observed early loss of subsarcolemmal neuronal nitric oxide synthase activity, onset of oxidative stress, intracellular lipid accumulation and post-translational protein modifications strongly argue for significant qualitative changes in contractile proteins causing the severely impaired residual function in diaphragm fibres after long-term mechanical ventilation. For the first time, the present study demonstrates

  18. Time course analysis of mechanical ventilation-induced diaphragm contractile muscle dysfunction in the rat

    PubMed Central

    Corpeno, R; Dworkin, B; Cacciani, N; Salah, H; Bergman, H-M; Ravara, B; Vitadello, M; Gorza, L; Gustafson, A-M; Hedström, Y; Petersson, J; Feng, H-Z; Jin, J-P; Iwamoto, H; Yagi, N; Artemenko, K; Bergquist, J; Larsson, L

    2014-01-01

    Controlled mechanical ventilation (CMV) plays a key role in triggering the impaired diaphragm muscle function and the concomitant delayed weaning from the respirator in critically ill intensive care unit (ICU) patients. To date, experimental and clinical studies have primarily focused on early effects on the diaphragm by CMV, or at specific time points. To improve our understanding of the mechanisms underlying the impaired diaphragm muscle function in response to mechanical ventilation, we have performed time-resolved analyses between 6 h and 14 days using an experimental rat ICU model allowing detailed studies of the diaphragm in response to long-term CMV. A rapid and early decline in maximum muscle fibre force and preceding muscle fibre atrophy was observed in the diaphragm in response to CMV, resulting in an 85% reduction in residual diaphragm fibre function after 9–14 days of CMV. A modest loss of contractile proteins was observed and linked to an early activation of the ubiquitin proteasome pathway, myosin:actin ratios were not affected and the transcriptional regulation of myosin isoforms did not show any dramatic changes during the observation period. Furthermore, small angle X-ray diffraction analyses demonstrate that myosin can bind to actin in an ATP-dependent manner even after 9–14 days of exposure to CMV. Thus, quantitative changes in muscle fibre size and contractile proteins are not the dominating factors underlying the dramatic decline in diaphragm muscle function in response to CMV, in contrast to earlier observations in limb muscles. The observed early loss of subsarcolemmal neuronal nitric oxide synthase activity, onset of oxidative stress, intracellular lipid accumulation and post-translational protein modifications strongly argue for significant qualitative changes in contractile proteins causing the severely impaired residual function in diaphragm fibres after long-term mechanical ventilation. For the first time, the present study

  19. Lung stress, strain, and energy load: engineering concepts to understand the mechanism of ventilator-induced lung injury (VILI).

    PubMed

    Nieman, Gary F; Satalin, Joshua; Andrews, Penny; Habashi, Nader M; Gatto, Louis A

    2016-12-01

    It was recently shown that acute respiratory distress syndrome (ARDS) mortality has not been reduced in over 15 years and remains ~40 %, even with protective low tidal volume (LVt) ventilation. Thus, there is a critical need to develop novel ventilation strategies that will protect the lung and reduce ARDS mortality. Protti et al. have begun to analyze the impact of mechanical ventilation on lung tissue using engineering methods in normal pigs ventilated for 54 h. They used these methods to assess the impact of a mechanical breath on dynamic and static global lung strain and energy load. Strain is the change in lung volume in response to an applied stress (i.e., Tidal Volume-Vt). This study has yielded a number of exciting new concepts including the following: (1) Individual mechanical breath parameters (e.g., Vt or Plateau Pressure) are not directly correlated with VILI but rather any combination of parameters that subject the lung to excessive dynamic strain and energy/power load will cause VILI; (2) all strain is not equal; dynamic strain resulting in a dynamic energy load (i.e., kinetic energy) is more damaging to lung tissue than static strain and energy load (i.e., potential energy); and (3) a critical consideration is not just the size of the Vt but the size of the lung that is being ventilated by this Vt. This key concept merits attention since our current protective ventilation strategies are fixated on the priority of keeping the Vt low. If the lung is fully inflated, a large Vt is not necessarily injurious. In conclusion, using engineering concepts to analyze the impact of the mechanical breath on the lung is a novel new approach to investigate VILI mechanisms and to help design the optimally protective breath. Data generated using these methods have challenged some of the current dogma surrounding the mechanisms of VILI and of the components in the mechanical breath necessary for lung protection.

  20. State of the Art: Neonatal Non-invasive Respiratory Support: Physiological Implications

    PubMed Central

    Shaffer, Thomas H.; Alapati, Deepthi; Greenspan, Jay S.; Wolfson, Marla R.

    2013-01-01

    Summary The introduction of assisted ventilation for neonatal pulmonary insufficiency has resulted in the successful treatment of many previously fatal diseases. During the past three decades, refinement of invasive mechanical ventilation techniques has dramatically improved survival of many high-risk neonates. However, as with many advances in medicine, while mortality has been reduced, morbidity has increased in the surviving high-risk neonate. In this regard, introduction of assisted ventilation has been associated with chronic lung injury, also known as bronchopulmonary dysplasia. This disease, unknown prior to the appearance of mechanical ventilation, has produced a population of patients characterized by ventilator or oxygen dependence with serious accompanying pulmonary and neurodevelopmental morbidity. The purpose of this article is to review non-invasive respiratory support methodologies to address the physiologic mechanisms by which these methods may prevent the pathophysiologic effects of invasive mechanical ventilation. PMID:22777738

  1. Effect of ultra-fast mild hypothermia using total liquid ventilation on hemodynamics and respiratory mechanics.

    PubMed

    Sage, Michaël; Nadeau, Mathieu; Kohlhauer, Matthias; Praud, Jean-Paul; Tissier, Renaud; Robert, Raymond; Walti, Hervé; Micheau, Philippe

    2016-08-01

    Ultra-fast cooling for mild therapeutic hypothermia (MTH) has several potential applications, including prevention of post-cardiac arrest syndrome. Ultra-fast MTH by total liquid ventilation (TLV) entails the sudden filling of the lungs with a cold perfluorocarbon liquid and its subsequent use to perform TLV. The present physiological study was aimed at assessing whether pulmonary and systemic hemodynamics as well as lung mechanics are significantly altered during this procedure. Pulmonary and systemic arterial pressures, cardiac output as well as airway resistance and respiratory system compliance were measured during ultra-fast MTH by TLV followed by rewarming and normothermia in six healthy juvenile lambs. Results show that none of the studied variables were altered upon varying the perfluorocarbon temperature from 12 to 41 °C. It is concluded that ultra-fast MTH by TLV does not have any deleterious effect on hemodynamics or lung mechanics in healthy juvenile lambs.

  2. The effects of open lung ventilation on respiratory mechanics and haemodynamics in atelectatic infants after cardiopulmonary bypass.

    PubMed

    Cui, Q; Zhou, H; Zhao, R; Liu, J; Yang, X; Zhu, H; Zheng, Q; Gu, C; Yi, D

    2009-01-01

    Acute lung injury (ALI) frequently occurs in infants after cardiopulmonary bypass (CPB) surgery and it sometimes develops into acute respiratory distress syndrome in critically ill infants, which can be life threatening. This study investigated the effects of open lung ventilation on the haemodynamics and respiratory mechanics of 64 infants (34 males; 30 females) with a mean +/- SD age of 8.3 +/- 0.3 months who developed ALI following CPB surgery. Open lung ventilation significantly improved the respiratory mechanics and oxygenation parameters of the infants, including the partial pressure of oxygen in arterial blood (PaO(2)), the ratio of PaO(2)/FiO(2) (fraction of inspired oxygen), peak inspiratory pressure, static compliance and airway resistance. It is concluded that open lung ventilation can greatly improve oxygenation and respiratory mechanics in infants with ALI following CPB surgery.

  3. Bronchopleural Fistula Resolution with Endobronchial Valve Placement and Liberation from Mechanical Ventilation in Acute Respiratory Distress Syndrome: A Case Series

    PubMed Central

    2017-01-01

    Patients who have acute respiratory distress syndrome (ARDS) with persistent air leaks have worse outcomes. Endobronchial valves (EBV) are frequently deployed after pulmonary resection in noncritically ill patients to reduce and eliminate bronchopleural fistulas (BPFs) with persistent air leak (PAL). Information regarding EBV placement in mechanically ventilated patients with ARDS and high volume persistent air leaks is rare and limited to case reports. We describe three cases where EBV placement facilitated endotracheal extubation in patients with severe respiratory failure on prolonged mechanical ventilation with BPFs. In each case, EBV placement led to immediate resolution of PAL. We believe endobronchial valve placement is a safe method treating persistent air leak with severe respiratory failure and may reduce days on mechanical ventilation. PMID:28367339

  4. Limitations of split-night polysomnography for the diagnosis of nocturnal hypoventilation and titration of non-invasive positive pressure ventilation in amyotrophic lateral sclerosis.

    PubMed

    Loewen, Andrea H S; Korngut, Lawrence; Rimmer, Karen; Damji, Omar; Turin, Tanvir C; Hanly, Patrick J

    2014-12-01

    Split-night polysomnography is performed at our centre in all patients with ALS who require assessment for nocturnal hypoventilation and their response to non-invasive ventilation. The purpose of this study was to determine how successful this practice has been, reflected by whether a complete assessment was achieved by a single split-night polysomnogram. We undertook a systematic, retrospective review of all consecutive split-night polysomnograms in ALS patients between 2005 and 2012. A total of 47 cases were reviewed. Forty-three percent of patients had an incomplete test, resulting in a recommendation to repeat the polysomnogram. Poor sleep efficiency and absence of REM sleep in the diagnostic portion of the study were strongly associated with incomplete studies. Clinical variables that reflect severity of ALS (FVC, PaCO2, ALSFRS-R) and use of REM-suppressing antidepressants or sedative-hypnotics were not associated with incomplete split-night polysomnogram. In conclusion, a single, split-night polysomnogram is frequently inconclusive for the assessment of nocturnal hypoventilation and complete titration of non-invasive positive pressure ventilation in patients with ALS. Poor sleep efficiency and absence of REM sleep are the main limitations of split-night polysomnography in this patient population.

  5. Respiratory mechanics during high-frequency oscillatory ventilation: a physical model and preterm infant study.

    PubMed

    Singh, Rachana; Courtney, Sherry E; Weisner, Michael D; Habib, Robert H

    2012-04-01

    Accurate mechanics measurements during high-frequency oscillatory ventilation (HFOV) facilitate optimizing ventilator support settings. Yet, these are influenced substantially by endotracheal tube (ETT) contributions, which may dominate when leaks around uncuffed ETT are present. We hypothesized that 1) the effective removal of ETT leaks may be confirmed via direct comparison of measured vs. model-predicted mean intratracheal pressure [mPtr (meas) vs. mPtr (pred)], and 2) reproducible respiratory system resistance (Rrs) and compliance (Crs) may be derived from no-leak oscillatory Ptr and proximal flow. With the use of ETT test-lung models, proximal airway opening (Pao) and distal (Ptr) pressures and flows were measured during slow-cuff inflations until leaks are removed. These were repeated for combinations of HFOV settings [frequency, mean airway pressure (Paw), oscillation amplitudes (ΔP), and inspiratory time (%t(I))] and varying test-lung Crs. Results showed that leaks around the ETT will 1) systematically reduce the effective distending pressures and lung-delivered oscillatory volumes, and 2) derived mechanical properties are increasingly nonphysiologic as leaks worsen. Mean pressures were systematically reduced along the ventilator circuit and ETT (Paw > Pao > Ptr), even for no-leak conditions. ETT size-specific regression models were then derived for predicting mPtr based on mean Pao (mPao), ΔP, %t(I), and frequency. Next, in 10 of 11 studied preterm infants (0.77 ± 0.24 kg), no-to-minimal leak was confirmed based on excellent agreement between mPtr (meas) and mPtr (pred), and consequently, their oscillatory respiratory mechanics were evaluated. Infant resistance at the proximal ETT (R(ETT); resistance airway opening = R(ETT) + Rrs; P < 0.001) and ETT inertance (P = 0.014) increased significantly with increasing ΔP (50%, 100%, and 150% baseline), whereas Rrs showed a modest, nonsignificant increase (P = 0.14), and Crs was essentially unchanged (P = 0

  6. Composition and distribution of particulate matter (PM10) in a mechanically ventilated University building

    NASA Astrophysics Data System (ADS)

    Ali, Mohamed Yasreen Mohamed; Hanafiah, Marlia Mohd; Latif, Mohd Talib

    2016-11-01

    This study analyses the composition and distribution of particulate matter (PM10) in the Biology department building, in UKM. PM10 were collected using SENSIDYNE Gillian GilAir-5 Personal Air Sampling System, a low-volume sampler, whereas the concentration of heavy metals was determined using Inductively coupled plasma-mass spectrometry (ICP-MS). The concentration of PM10 recorded in the mechanically ventilated building ranges from 89 µgm-3 to 910 µgm-3. The composition of the selected heavy metals in PM10 were dominated by zinc, followed by copper, lead and cadmium. It was found that the present of indoor-related particulate matter were originated from the poorly maintained ventilation system, the activity of occupants and typical office equipments such as printers and photocopy machines. The haze event occured during sampling periods was also affected the PM10 concentration in the building. This results can serve as a starting point to assess the potential human health damage using the life cycle impact assessment, expressed in term of disability adjusted life year (DALY).

  7. A novel preterm respiratory mechanics active simulator to test the performances of neonatal pulmonary ventilators

    NASA Astrophysics Data System (ADS)

    Cappa, Paolo; Sciuto, Salvatore Andrea; Silvestri, Sergio

    2002-06-01

    A patient active simulator is proposed which is capable of reproducing values of the parameters of pulmonary mechanics of healthy newborns and preterm pathological infants. The implemented prototype is able to: (a) let the operator choose the respiratory pattern, times of apnea, episodes of cough, sobs, etc., (b) continuously regulate and control the parameters characterizing the pulmonary system; and, finally, (c) reproduce the attempt of breathing of a preterm infant. Taking into account both the limitation due to the chosen application field and the preliminary autocalibration phase automatically carried out by the proposed device, accuracy and reliability on the order of 1% is estimated. The previously indicated value has to be considered satisfactory in light of the field of application and the small values of the simulated parameters. Finally, the achieved metrological characteristics allow the described neonatal simulator to be adopted as a reference device to test performances of neonatal ventilators and, more specifically, to measure the time elapsed between the occurrence of a potentially dangerous condition to the patient and the activation of the corresponding alarm of the tested ventilator.

  8. Role of mechanical ventilation in the airborne transmission of infectious agents in buildings.

    PubMed

    Luongo, J C; Fennelly, K P; Keen, J A; Zhai, Z J; Jones, B W; Miller, S L

    2016-10-01

    Infectious disease outbreaks and epidemics such as those due to SARS, influenza, measles, tuberculosis, and Middle East respiratory syndrome coronavirus have raised concern about the airborne transmission of pathogens in indoor environments. Significant gaps in knowledge still exist regarding the role of mechanical ventilation in airborne pathogen transmission. This review, prepared by a multidisciplinary group of researchers, focuses on summarizing the strengths and limitations of epidemiologic studies that specifically addressed the association of at least one heating, ventilating and/or air-conditioning (HVAC) system-related parameter with airborne disease transmission in buildings. The purpose of this literature review was to assess the quality and quantity of available data and to identify research needs. This review suggests that there is a need for well-designed observational and intervention studies in buildings with better HVAC system characterization and measurements of both airborne exposures and disease outcomes. Studies should also be designed so that they may be used in future quantitative meta-analyses.

  9. Cardiorespiratory Mechanical Simulator for In Vitro Testing of Impedance Minute Ventilation Sensors in Cardiac Pacemakers.

    PubMed

    Marcelli, Emanuela; Cercenelli, Laura

    2016-01-01

    We developed a cardiorespiratory mechanical simulator (CRMS), a system able to reproduce both the cardiac and respiratory movements, intended to be used for in vitro testing of impedance minute ventilation (iMV) sensors in cardiac pacemakers. The simulator consists of two actuators anchored to a human thorax model and a software interface to control the actuators and to acquire/process impedance signals. The actuators can be driven separately or simultaneously to reproduce the cardiac longitudinal shortening at a programmable heart rate and the diaphragm displacement at a programmable respiratory rate (RR). A standard bipolar pacing lead moving with the actuators and a pacemaker case fixed to the thorax model have been used to measure impedance (Z) variations during the simulated cardiorespiratory movements. The software is able to discriminate the low-frequency component because of respiration (Z(R)) from the high-frequency ripple because of cardiac effect (Z(C)). Impedance minute ventilation is continuously calculated from Z(R) and RR. From preliminary tests, the CRMS proved to be a reliable simulator for in vitro evaluation of iMV sensors. Respiration impedance recordings collected during cardiorespiratory movements reproduced by the CRMS were comparable in morphology and amplitude with in vivo assessments of transthoracic impedance variations.

  10. Analysis of multiple linear regression algorithms used for respiratory mechanics monitoring during artificial ventilation.

    PubMed

    Polak, Adam G

    2011-02-01

    Many patients undergo long-term artificial ventilation and their respiratory system mechanics should be monitored to detect changes in the patient's state and to optimize ventilator settings. In this work the most popular algorithms for tracking variations of respiratory resistance (R(rs)) and elastance (E(rs)) over a ventilatory cycle were analysed in terms of systematic and random errors. Additionally, a new approach was proposed and compared to the previous ones. It takes into account an exact description of flow integration by volume-dependent lung compliance. The results of analyses showed advantages of this new approach and enabled to form several suggestions. Algorithms including R(rs) and E(rs) dependencies on airflow and lung volume can be effectively applied only at low levels of noise present in measurement data, otherwise the use of the simplest model with constant parameters is preferable. Additionally, one should avoid including the resistance dependence on airflow alone, since this considerably destroys the retrieved trace of R(rs). Finally, the estimated cyclic trajectories of R(rs) and E(rs) are more sensitive to noise present in pressure than in the flow signal, and the elastance traces are estimated more accurately than the resistance ones.

  11. Randomised controlled comparison of continuous positive airways pressure, bilevel non-invasive ventilation, and standard treatment in emergency department patients with acute cardiogenic pulmonary oedema

    PubMed Central

    Crane, S; Elliott, M; Gilligan, P; Richards, K; Gray, A

    2004-01-01

    Background: Continuous positive airways pressure (CPAP) and bilevel non-invasive ventilation may have beneficial effects in the treatment of patients with acute cardiogenic pulmonary oedema. The efficacy of both treatments was assessed in the UK emergency department setting, in a randomised comparison with standard oxygen therapy. Methods: Sixty patients presenting with acidotic (pH<7.35) acute, cardiogenic pulmonary oedema, were randomly assigned conventional oxygen therapy, CPAP (10 cm H2O), or bilevel ventilation (IPAP 15 cm H2O, EPAP 5 cm H2O) provided by a standard ventilator through a face mask. The main end points were treatment success at two hours and in-hospital mortality. Analyses were by intention to treat. Results: Treatment success (defined as all of respiratory rate<23 bpm, oxygen saturation of>90%, and arterial blood pH>7.35 (that is, reversal of acidosis), at the end of the two hour study period) occurred in three (15%) patients in the control group, seven (35%) in the CPAP group, and nine (45%) in the bilevel group (p = 0.116). Fourteen (70%) of the control group patients survived to hospital discharge, compared with 20 (100%) in the CPAP group and 15 (75%) in the bilevel group (p = 0.029; Fisher's test). Conclusions: In this study, patients presenting with acute cardiogenic pulmonary oedema and acidosis, were more likely to survive to hospital discharge if treated with CPAP, rather than with bilevel ventilation or with conventional oxygen therapy. There was no relation between in hospital survival and early physiological changes. Survival rates were similar to other studies despite a low rate of endotracheal intubation. PMID:14988338

  12. Test-retest reliability of expiratory abdominal compression with a handheld dynamometer in patients with prolonged mechanical ventilation.

    PubMed

    Morino, Akira; Shida, Masahiro; Tanaka, Masashi; Sato, Kimihiro; Seko, Toshiaki; Ito, Shunsuke; Ogawa, Shunichi; Takahashi, Naoaki

    2015-07-01

    [Purpose] The present study aimed to examine the test-retest reliability of expiratory abdominal compression with a handheld dynamometer in patients with prolonged mechanical ventilation. [Subjects and Methods] We recruited 18 patients with prolonged mechanical ventilation. All patients had impaired consciousness. The mode of the ventilator was synchronized intermittent mandatory ventilation. The abdomen above the navel was vertically compressed using a handheld dynamometer in synchronization with expiration. Expiratory abdominal compression was performed two times. We measured the tidal volume during expiratory abdominal compression. There was an interval of 5 minutes between the first and second measurements. Intraclass correlation coefficient (ICC) and Bland-Altman analysis were performed to examine the test-retest reliability of expiratory abdominal compression with a handheld dynamometer. [Results] The test-retest reliability of expiratory abdominal compression was excellent (ICC(1, 1): 0.987). Bland-Altman analysis showed that there was no fixed bias and no proportional bias. [Conclusion] The findings of this study suggest that expiratory abdominal compression with a handheld dynamometer is reliable and useful for patients with respiratory failure and prolonged mechanical ventilation.

  13. Test-retest reliability of expiratory abdominal compression with a handheld dynamometer in patients with prolonged mechanical ventilation

    PubMed Central

    Morino, Akira; Shida, Masahiro; Tanaka, Masashi; Sato, Kimihiro; Seko, Toshiaki; Ito, Shunsuke; Ogawa, Shunichi; Takahashi, Naoaki

    2015-01-01

    [Purpose] The present study aimed to examine the test-retest reliability of expiratory abdominal compression with a handheld dynamometer in patients with prolonged mechanical ventilation. [Subjects and Methods] We recruited 18 patients with prolonged mechanical ventilation. All patients had impaired consciousness. The mode of the ventilator was synchronized intermittent mandatory ventilation. The abdomen above the navel was vertically compressed using a handheld dynamometer in synchronization with expiration. Expiratory abdominal compression was performed two times. We measured the tidal volume during expiratory abdominal compression. There was an interval of 5 minutes between the first and second measurements. Intraclass correlation coefficient (ICC) and Bland-Altman analysis were performed to examine the test-retest reliability of expiratory abdominal compression with a handheld dynamometer. [Results] The test-retest reliability of expiratory abdominal compression was excellent (ICC(1, 1): 0.987). Bland-Altman analysis showed that there was no fixed bias and no proportional bias. [Conclusion] The findings of this study suggest that expiratory abdominal compression with a handheld dynamometer is reliable and useful for patients with respiratory failure and prolonged mechanical ventilation. PMID:26311946

  14. Mechanical ventilation weaning in inclusion body myositis: feasibility of isokinetic inspiratory muscle training as an adjunct therapy.

    PubMed

    Cordeiro de Souza, Leonardo; Campos, Josué Felipe; Daher, Leandro Possidente; Furtado da Silva, Priscila; Ventura, Alex; do Prado, Pollyana Zamborlini; Brasil, Daniele; Mendonça, Debora; Lugon, Jocemir Ronaldo

    2014-01-01

    Inclusion body myositis is a rare myopathy associated with a high rate of respiratory complications. This condition usually requires prolonged mechanical ventilation and prolonged intensive care stay. The unsuccessful weaning is mainly related to respiratory muscle weakness that does not promptly respond to immunosuppressive therapy. We are reporting a case of a patient in whom the use of an inspiratory muscle-training program which started after a two-week period of mechanical ventilation was associated with a successful weaning in one week and hospital discharge after 2 subsequent weeks.

  15. Mechanical Ventilation Weaning in Inclusion Body Myositis: Feasibility of Isokinetic Inspiratory Muscle Training as an Adjunct Therapy

    PubMed Central

    Campos, Josué Felipe; Daher, Leandro Possidente; Ventura, Alex; do Prado, Pollyana Zamborlini; Brasil, Daniele; Mendonça, Debora; Lugon, Jocemir Ronaldo

    2014-01-01

    Inclusion body myositis is a rare myopathy associated with a high rate of respiratory complications. This condition usually requires prolonged mechanical ventilation and prolonged intensive care stay. The unsuccessful weaning is mainly related to respiratory muscle weakness that does not promptly respond to immunosuppressive therapy. We are reporting a case of a patient in whom the use of an inspiratory muscle-training program which started after a two-week period of mechanical ventilation was associated with a successful weaning in one week and hospital discharge after 2 subsequent weeks. PMID:25147743

  16. Association of Increasing Use of Mechanical Ventilation Among Nursing Home Residents With Advanced Dementia and Intensive Care Unit Beds

    PubMed Central

    Teno, Joan M.; Gozalo, Pedro; Khandelwal, Nita; Curtis, J. Randall; Meltzer, David; Engelberg, Ruth; Mor, Vincent

    2016-01-01

    IMPORTANCE Mechanical ventilation may be lifesaving, but in certain persons, such as those with advanced dementia, it may prolong patient suffering without a clear survival benefit. OBJECTIVE To describe the use and outcomes of mechanical ventilation and its association with the increasing numbers of intensive care unit (ICU) beds in the United States for patients with advanced dementia residing in a nursing home 120 days before that hospital admission. DESIGN, SETTING, AND PARTICIPANTS This retrospective cohort study evaluated Medicare beneficiaries with advanced dementia hospitalized from January 1, 2000, to December 31, 2013, using the Minimum Data Set assessments linked with Medicare part A claims. A hospital fixed-effect, multivariable logistic regression model examined the effect of changes in ICU beds within individual hospitals and the likelihood of receiving mechanical ventilation, controlling for patients’ demographic characteristics, function, and comorbidities. MAIN OUTCOMES AND MEASURES Mechanical ventilation. RESULTS From 2000 to 2013, a total of 635 008 hospitalizations of 380 060 eligible patients occurred (30.5% male and 69.5% female; mean [SD] age, 84.4 [7.4] years). Use of mechanical ventilation increased from 39 per 1000 hospitalizations in 2000 to 78 per 1000 hospitalizations in 2013 (P < .001, test of linear trend). As the number of ICU beds in a hospital increased over time, patients with advanced dementia were more likely to receive mechanical ventilation (ie, adjusted odds ratio per 10 ICU bed increase, 1.06; 95% CI, 1.05–1.07). In 2013, hospitals in the top decile in the number of ICU beds were reimbursed $9611.89 per hospitalization compared with $8050.24 per hospitalization in the lower decile (P < .001) without an improvement in 1-year mortality (65.2% vs 64.6%; P = 54). CONCLUSIONS AND RELEVANCE Among hospitalized nursing home residents with advanced dementia, we found an increase in the use of mechanical ventilation over time

  17. Effects of Different Peep Levels on Mesenteric Leukocyte-Endothelial Interactions in Rats During Mechanical Ventilation

    PubMed Central

    Aikawa, Priscila; Farsky, Sandra Helena Poliselli; de Oliveira, Maria Aparecida; Pazetti, Rogério; Mauad, Thaís; Sannomiya, Paulina; Nakagawa, Naomi Kondo

    2009-01-01

    INTRODUCTION: Mechanical ventilation with positive end expiratory pressure (PEEP) improves oxygenation and treats acute pulmonary failure. However, increased intrathoracic pressure may cause regional blood flow alterations that may contribute to mesenteric ischemia and gastrointestinal failure. We investigated the effects of different PEEP levels on mesenteric leukocyte-endothelial interactions. METHODS: Forty-four male Wistar rats were initially anesthetized (Pentobarbital I.P. 50mg/kg) and randomly assigned to one of the following groups: 1) NAIVE (only anesthesia; n=9), 2) PEEP 0 (PEEP of 0 cmH2O, n=13), 3) PEEP 5 (PEEP of 5 cmH2O, n=12), and 4) PEEP 10 (PEEP of 10 cmH2O, n=13). Positive end expiratory pressure groups were tracheostomized and mechanically ventilated with a tidal volume of 10 mL/kg, respiratory rate of 70 rpm, and inspired oxygen fraction of 1. Animals were maintained under isoflurane anesthesia. After two hours, laparotomy was performed, and leukocyte-endothelial interactions were evaluated by intravital microscopy. RESULTS: No significant changes were observed in mean arterial blood pressure among groups during the study. Tracheal peak pressure was smaller in PEEP 5 compared with PEEP 0 and PEEP 10 groups (11, 15, and 16 cmH2O, respectively; p<0.05). After two hours of MV, there were no differences among NAIVE, PEEP 0 and PEEP 5 groups in the number of rollers (118±9,127±14 and 147±26 cells/10minutes, respectively), adherent leukocytes (3±1,3±1 and 4±2 cells/100μm venule length, respectively), and migrated leukocytes (2±1,2±1 and 2±1 cells/5,000μm2, respectively) at the mesentery. However, the PEEP 10 group exhibited an increase in the number of rolling, adherent and migrated leukocytes (188±15 cells / 10 min, 8±1 cells / 100 μm and 12±1 cells / 5,000 μm2, respectively; p<0.05). CONCLUSIONS: High intrathoracic pressure was harmful to mesenteric microcirculation in the experimental model of rats with normal lungs and stable

  18. Effect of tracheal suctioning on aspiration past the tracheal tube cuff in mechanically ventilated patients

    PubMed Central

    2012-01-01

    Background This clinical study evaluated the effect of a suctioning maneuver on aspiration past the cuff during mechanical ventilation. Methods Patients intubated for less than 48 hours with a PVC-cuffed tracheal tube, under mechanical ventilation with a PEEP ≥5 cm H2O and under continuous sedation, were included in the study. At baseline the cuff pressure was set at 30 cm H2O. Then 0.5ml of blue dye diluted with 3 ml of saline was instilled into the subglottic space just above the cuff. Tracheal suctioning was performed using a 16-French suction catheter with a suction pressure of – 400 mbar. A fiberoptic bronchoscopy was performed before and after the suctioning maneuver, looking for the presence of blue dye in the folds within the cuff wall or in the trachea under the cuff. The sealing of the cuff was defined by the absence of leakage of blue dye either in the cuff wall or in the trachea under the cuff. Results Twenty-five patients were included. The size of the tracheal tube was 7-mm ID for 5 patients, 7.5-mm ID for 16 patients, and 8-mm ID for four patients. Blue dye was never seen in the trachea under the cuff before suctioning and only in one patient (4%) after the suctioning maneuver. Blue dye was observed in the folds within the cuff wall in 6 of 25 patients before suctioning and 11 of 25 after (p = 0.063). Overall, the incidence of sealing of the cuff was 76% before suctioning and 56% after (p = 0.073). Conclusions In patients intubated with a PVC-cuffed tracheal tube and under mechanical ventilation with PEEP ≥5 cm H2O and a cuff pressure set at 30 cm H2O, a single tracheal suctioning maneuver did not increase the risk of aspiration in the trachea under the cuff. Trial registration ClinicalTrials.gov, number NCT01170156 PMID:23134813

  19. Instantaneous responses to high-frequency chest wall oscillation in patients with acute pneumonic respiratory failure receiving mechanical ventilation

    PubMed Central

    Chuang, Ming-Lung; Chou, Yi-Ling; Lee, Chai-Yuan; Huang, Shih-Feng

    2017-01-01

    Abstract Background: Endotracheal intubation and prolonged immobilization of patients receiving mechanical ventilation may reduce expectoration function. High-frequency chest wall oscillation (HFCWO) may ameliorate airway secretion movement; however, the instantaneous changes in patients’ cardiopulmonary responses are unknown. Moreover, HFCWO may influence ventilator settings by the vigorous oscillation. The aim of this study was to investigate these issues. Methods: Seventy-three patients (52 men) aged 71.5 ± 13.4 years who were intubated with mechanical ventilation for pneumonic respiratory failure were recruited and randomly classified into 2 groups (HFCWO group, n = 36; and control group who received conventional chest physical therapy (CCPT, n = 37). HFCWO was applied with a fixed protocol, whereas CCPT was conducted using standard protocols. Both groups received sputum suction after the procedure. Changes in ventilator settings and the subjects’ responses were measured at preset intervals and compared within groups and between groups. Results: Oscillation did not affect the ventilator settings (all P > 0.05). The mean airway pressure, breathing frequency, and rapid shallow breathing index increased, and the tidal volume and SpO2 decreased (all P < 0.05). After sputum suction, the peak airway pressure (Ppeak) and minute ventilation decreased (all P < 0.05). The HFCWO group had a lower tidal volume and SpO2 at the end of oscillation, and lower Ppeak and tidal volume after sputum suction than the CCPT group. Conclusions: HFCWO affects breathing pattern and SpO2 but not ventilator settings, whereas CCPT maintains a steadier condition. After sputum suction, HFCWO slightly improved Ppeak compared to CCPT, suggesting that the study extends the indications of HFCWO for these patients in intensive care unit. (ClinicalTrials.gov number NCT02758106, retrospectively registered.) PMID:28248854

  20. Mechanical ventilation-associated lung fibrosis in acute respiratory distress syndrome: a significant contributor to poor outcome.

    PubMed

    Cabrera-Benitez, Nuria E; Laffey, John G; Parotto, Matteo; Spieth, Peter M; Villar, Jesús; Zhang, Haibo; Slutsky, Arthur S

    2014-07-01

    One of the most challenging problems in critical care medicine is the management of patients with the acute respiratory distress syndrome. Increasing evidence from experimental and clinical studies suggests that mechanical ventilation, which is necessary for life support in patients with acute respiratory distress syndrome, can cause lung fibrosis, which may significantly contribute to morbidity and mortality. The role of mechanical stress as an inciting factor for lung fibrosis versus its role in lung homeostasis and the restoration of normal pulmonary parenchymal architecture is poorly understood. In this review, the authors explore recent advances in the field of pulmonary fibrosis in the context of acute respiratory distress syndrome, concentrating on its relevance to the practice of mechanical ventilation, as commonly applied by anesthetists and intensivists. The authors focus the discussion on the thesis that mechanical ventilation-or more specifically, that ventilator-induced lung injury-may be a major contributor to lung fibrosis. The authors critically appraise possible mechanisms underlying the mechanical stress-induced lung fibrosis and highlight potential therapeutic strategies to mitigate this fibrosis.

  1. Mechanisms of CNS invasion and damage by parasites.

    PubMed

    Kristensson, Krister; Masocha, Willias; Bentivoglio, Marina

    2013-01-01

    Invasion of the central nervous system (CNS) is a most devastating complication of a parasitic infection. Several physical and immunological barriers provide obstacles to such an invasion. In this broad overview focus is given to the physical barriers to neuroinvasion of parasites provided at the portal of entry of the parasites, i.e., the skin and epithelial cells of the gastrointestinal tract, and between the blood and the brain parenchyma, i.e., the blood-brain barrier (BBB). A description is given on how human pathogenic parasites can reach the CNS via the bloodstream either as free-living or extracellular parasites, by embolization of eggs, or within red or white blood cells when adapted to intracellular life. Molecular mechanisms are discussed by which parasites can interact with or pass across the BBB. The possible targeting of the circumventricular organs by parasites, as well as the parasites' direct entry to the brain from the nasal cavity through the olfactory nerve pathway, is also highlighted. Finally, examples are given which illustrate different mechanisms by which parasites can cause dysfunction or damage in the CNS related to toxic effects of parasite-derived molecules or to immune responses to the infection.

  2. A respiratory-gated micro-CT comparison of respiratory patterns in free-breathing and mechanically ventilated rats.

    PubMed

    Ford, Nancy L; McCaig, Lynda; Jeklin, Andrew; Lewis, James F; Veldhuizen, Ruud A W; Holdsworth, David W; Drangova, Maria

    2017-01-01

    In this study, we aim to quantify the differences in lung metrics measured in free-breathing and mechanically ventilated rodents using respiratory-gated micro-computed tomography. Healthy male Sprague-Dawley rats were anesthetized with ketamine/xylazine and scanned with a retrospective respiratory gating protocol on a GE Locus Ultra micro-CT scanner. Each animal was scanned while free-breathing, then intubated and mechanically ventilated (MV) and rescanned with a standard ventilation protocol (56 bpm, 8 mL/kg and PEEP of 5 cm H2O) and again with a ventilation protocol that approximates the free-breathing parameters (88 bpm, 2.14 mL/kg and PEEP of 2.5 cm H2O). Images were reconstructed representing inspiration and end expiration with 0.15 mm voxel spacing. Image-based measurements of the lung lengths, airway diameters, lung volume, and air content were compared and used to calculate the functional residual capacity (FRC) and tidal volume. Images acquired during MV appeared darker in the airspaces and the airways appeared larger. Image-based measurements showed an increase in lung volume and air content during standard MV, for both respiratory phases, compared with matched MV and free-breathing. Comparisons of the functional metrics showed an increase in FRC for mechanically ventilated rats, but only the standard MV exhibited a significantly higher tidal volume than free-breathing or matched MV Although standard mechanical ventilation protocols may be useful in promoting consistent respiratory patterns, the amount of air in the lungs is higher than in free-breathing animals. Matching the respiratory patterns with the free-breathing case allowed similar lung morphology and physiology measurements while reducing the variability in the measurements.

  3. Simultaneous temperature and humidity measurements in a mechanical ventilator using an optical fibre sensor

    NASA Astrophysics Data System (ADS)

    Hernandez, F. U.; Correia, R.; Morgan, S. P.; Hayes-Gill, B.; Evans, D.; Sinha, R.; Norris, A.; Harvey, D.; Hardman, J. G.; Korposh, S.

    2016-05-01

    An optical fibre sensor for simultaneous temperature and humidity measurements consisting of one fibre Bragg grating (FBG) to measure temperature and a mesoporous film of bilayers of Poly(allylamine hydrochloride)(PAH) and silica (SiO2) nanoparticles deposited onto the tip of the same fibre to measure humidity is reported. The hygroscopic film was created using the layer-by-layer (LbL) method and the optical reflection spectra were measured up to a maximum of 23 bilayers. The temperature sensitivity of the FBG was 10 pm/°C while the sensitivity to humidity was (-1.4x10-12 W / %RH) using 23 bilayers. The developed sensor was tested in the mechanical ventilator and temperature and humidity of the delivered artificial air was simultaneously measured. Once calibrated, the optical fibre sensor has the potential to control the absolute humidity as an essential part of critical respiratory care.

  4. Prevalence of Advance Directives Among Older Adults Admitted to Intensive Care Units and Requiring Mechanical Ventilation.

    PubMed

    Gamertsfelder, Elise M; Seaman, Jennifer Burgher; Tate, Judith; Buddadhumaruk, Praewpannarai; Happ, Mary Beth

    2016-04-01

    Because older adults are at high risk for hospitalization and potential decisional incapacity, advance directives are important components of pre-hospital advanced care planning, as they document individual preferences for future medical care. The prevalence of pre-hospital advance directive completion in 450 critically ill older adults requiring mechanical ventilation from two Mid-Atlantic hospitals is described, and demographic and clinical predictors of pre-hospital advance directive completion are explored. The overall advance directive completion rate was 42.4%, with those in older age groups (75 to 84 years and 85 and older) having approximately two times the odds of completion. No significant differences in the likelihood of advance directive completion were noted by sex, race, or admitting diagnosis. The relatively low prevalence of advance directive completion among older adults with critical illness and high mortality rate (24%) suggest a need for greater awareness and education.

  5. [Helicopter transportation of a sedated, mechanically ventilated patient with cervical cord injury].

    PubMed

    Kato, Hideya; Nishiwaki, Yuko; Hosoi, Kunihiko; Shiomi, Naoto; Hirata, Masashi

    2013-09-01

    We report helicopter transportation of a sedated, mechanically ventilated patient with cervical cord injury. A 20-year-old male sustained traumatic injury to the cervical spinal cord during extracurricular activities in a college. On arrival at the hospital, a halo vest was placed on the patient and tracheostomy was performed. On the 38th hospital day, he was transported a distance of 520km by helicopter to a specialized hospital in Fukuoka for medical repatriation. Cabin space was narrow. Since power supply and carrying capacity were limited, battery-driven and portable medical devices were used. In consideration for patient's psychological stress, he was sedated with propofol. RSS (Ramsay sedation scale) scores were recorded to evaluate whether the patient was adequately sedated during helicopter transportation. Prior to transport, we rehearsed the sedation using bispectral index monitoring (BIS) in the hospital to further ensure the patient's safety during the transport.

  6. [Assessment of Wiki technology: a tool for accessing information on mechanical ventilation in intensive care].

    PubMed

    Barra, Daniela Couto Carvalho; Dal Sasso, Grace Teresinha Marcon; Martins, Cleusa Rios; Barbosa, Sayonara de Fátima Faria

    2012-01-01

    The development and application of information technology influence all areas of knowledge, enabling new ways of learning. The Wiki is a tool of information and communication technology provided by the Web 2.0 that can be exploited and used in teaching, learning, care and research in nursing education. Thus, this quantitative study is a descriptive and exploratory objective was to evaluate the nursing students with the criteria of Ergonomics and Usability of the tool Wiki as a technology to access information on nursing care in mechanical ventilation in the Intensive Care Unit. The tool was evaluated as "excellent" in the criteria for Ergonomics and Usability, and is considered a new emerging technology suitable for educational use.

  7. Ventilation and ventilators.

    PubMed

    Hayes, B

    1982-01-01

    The history of ventilation is reviewed briefly and recent developments in techniques of ventilation are discussed. Operating features of ventilators have changed in the past few years, partly as the result of clinical progress; yet, technology appears to have outstripped the clinician's ability to harness it most effectively. Clinical discipline and training of medical staff in the use of ventilators could be improved. The future is promising if clinician and designer can work together closely. Ergonomics of ventilators and their controls and the provision of alarms need special attention. Microprocessors are likely to feature prominently in the next generation of designs.

  8. Liquid ventilation

    PubMed Central

    Sarkar, Suman; Paswan, Anil; Prakas, S.

    2014-01-01

    Human have lungs to breathe air and they have no gills to breath liquids like fish. When the surface tension at the air-liquid interface of the lung increases as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV) is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen as the inert carrier of oxygen and carbon dioxide offers a number of advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. It is well-known that respiratory diseases are one of the most common causes of morbidity and mortality in intensive care unit. During the past few years several new modalities of treatment have been introduced. One of them and probably the most fascinating, is of LV. Partial LV, on which much of the existing research has concentrated, requires partial filling of lungs with perfluorocarbons (PFC's) and ventilation with gas tidal volumes using conventional mechanical ventilators. Various physico-chemical properties of PFC's make them the ideal media. It results in a dramatic improvement in lung compliance and oxygenation and decline in mean airway pressure and oxygen requirements. No long-term side-effect reported. PMID:25886321

  9. Inspiratory muscle training to enhance recovery from mechanical ventilation: a randomised trial

    PubMed Central

    Bissett, Bernie M; Leditschke, I Anne; Neeman, Teresa; Boots, Robert; Paratz, Jennifer

    2016-01-01

    Background In patients who have been mechanically ventilated, inspiratory muscles remain weak and fatigable following ventilatory weaning, which may contribute to dyspnoea and limited functional recovery. Inspiratory muscle training may improve inspiratory muscle strength and endurance following weaning, potentially improving dyspnoea and quality of life in this patient group. Methods We conducted a randomised trial with assessor-blinding and intention-to-treat analysis. Following 48 hours of successful weaning, 70 participants (mechanically ventilated ≥7 days) were randomised to receive inspiratory muscle training once daily 5 days/week for 2 weeks in addition to usual care, or usual care (control). Primary endpoints were inspiratory muscle strength and fatigue resistance index (FRI) 2 weeks following enrolment. Secondary endpoints included dyspnoea, physical function and quality of life, post-intensive care length of stay and in-hospital mortality. Results 34 participants were randomly allocated to the training group and 36 to control. The training group demonstrated greater improvements in inspiratory strength (training: 17%, control: 6%, mean difference: 11%, p=0.02). There were no statistically significant differences in FRI (0.03 vs 0.02, p=0.81), physical function (0.25 vs 0.25, p=0.97) or dyspnoea (−0.5 vs 0.2, p=0.22). Improvement in quality of life was greater in the training group (14% vs 2%, mean difference 12%, p=0.03). In-hospital mortality was higher in the training group (4 vs 0, 12% vs 0%, p=0.051). Conclusions Inspiratory muscle training following successful weaning increases inspiratory muscle strength and quality of life, but we cannot confidently rule out an associated increased risk of in-hospital mortality. Trial registration number ACTRN12610001089022, results. PMID:27257003

  10. Early sedation and clinical outcomes of mechanically ventilated patients: a prospective multicenter cohort study

    PubMed Central

    2014-01-01

    Introduction Sedation overuse is frequent and possibly associated with poor outcomes in the intensive care unit (ICU) patients. However, the association of early oversedation with clinical outcomes has not been thoroughly evaluated. The aim of this study was to assess the association of early sedation strategies with outcomes of critically ill adult patients under mechanical ventilation (MV). Methods A secondary analysis of a multicenter prospective cohort conducted in 45 Brazilian ICUs, including adult patients requiring ventilatory support and sedation in the first 48 hours of ICU admissions, was performed. Sedation depth was evaluated after 48 hours of MV. Multivariate analysis was used to identify variables associated with hospital mortality. Results A total of 322 patients were evaluated. Overall, ICU and hospital mortality rates were 30.4% and 38.8%, respectively. Deep sedation was observed in 113 patients (35.1%). Longer duration of ventilatory support was observed (7 (4 to 10) versus 5 (3 to 9) days, P = 0.041) and more tracheostomies were performed in the deep sedation group (38.9% versus 22%, P = 0.001) despite similar PaO2/FiO2 ratios and acute respiratory distress syndrome (ARDS) severity. In a multivariate analysis, age (Odds Ratio (OR) 1.02; 95% confidence interval (CI) 1.00 to 1.03), Charlson Comorbidity Index >2 (OR 2.06; 95% CI, 1.44 to 2.94), Simplified Acute Physiology Score 3 (SAPS 3) score (OR 1.02; CI 95%, 1.00 to 1.04), severe ARDS (OR 1.44; CI 95%, 1.09 to 1.91) and deep sedation (OR 2.36; CI 95%, 1.31 to 4.25) were independently associated with increased hospital mortality. Conclusions Early deep sedation is associated with adverse outcomes and constitutes an independent predictor of hospital mortality in mechanically ventilated patients. PMID:25047960

  11. Absence of TNF-α enhances inflammatory response in the newborn lung undergoing mechanical ventilation.

    PubMed

    Ehrhardt, Harald; Pritzke, Tina; Oak, Prajakta; Kossert, Melina; Biebach, Luisa; Förster, Kai; Koschlig, Markus; Alvira, Cristina M; Hilgendorff, Anne

    2016-05-15

    Bronchopulmonary dysplasia (BPD), characterized by impaired alveolarization and vascularization in association with lung inflammation and apoptosis, often occurs after mechanical ventilation with oxygen-rich gas (MV-O2). As heightened expression of the proinflammatory cytokine TNF-α has been described in infants with BPD, we hypothesized that absence of TNF-α would reduce pulmonary inflammation, and attenuate structural changes in newborn mice undergoing MV-O2 Neonatal TNF-α null (TNF-α(-/-)) and wild type (TNF-α(+/+)) mice received MV-O2 for 8 h; controls spontaneously breathed 40% O2 Histologic, mRNA, and protein analysis in vivo were complemented by in vitro studies subjecting primary pulmonary myofibroblasts to mechanical stretch. Finally, TNF-α level in tracheal aspirates from preterm infants were determined by ELISA. Although MV-O2 induced larger and fewer alveoli in both, TNF-α(-/-) and TNF-α(+/+) mice, it caused enhanced lung apoptosis (TUNEL, caspase-3/-6/-8), infiltration of macrophages and neutrophils, and proinflammatory mediator expression (IL-1β, CXCL-1, MCP-1) in TNF-α(-/-) mice. These differences were associated with increased pulmonary transforming growth factor-β (TGF-β) signaling, decreased TGF-β inhibitor SMAD-7 expression, and reduced pulmonary NF-κB activity in ventilated TNF-α(-/-) mice. Preterm infants who went on to develop BPD showed significantly lower TNF-α levels at birth. Our results suggest a critical balance between TNF-α and TGF-β signaling in the developing lung, and underscore the critical importance of these key pathways in the pathogenesis of BPD. Future treatment strategies need to weigh the potential benefits of inhibiting pathologic cytokine expression against the potential of altering key developmental pathways.

  12. The application of mechanical aerosol delivery systems in an in vitro model of mechanically ventilated neonates.

    PubMed

    Ehtezazi, Touraj; Turner, Mark A

    2013-12-01

    Delivery of medication to the neonatal lung using current methods is inefficient. Aerosols offer one way to improve delivery to small airways. In this in vitro work, aerosol delivery by using a micropump or a rotary valve has been evaluated in a model of the neonatal setting with a pressurised metered dose inhaler plus spacer outside of the inspiratory limb. Drug depositions were assessed by spectrophotometric analyses. Drug lung deposition was increased by adjusting the rotary valve for co-ordination between the inhalation and aerosol delivery, but this intermittent mode decreased the aerosol delivery by using the micropump. Also, decreasing the volume of spacer decreased drug deposition in test lungs by using the micropump system. At the optimum conditions, the rotary valve aerosol delivery system delivered 3.68±0.91% of the Qvar nominal dose to the test lungs, and this was 2.34±0.01% for the micropump system. In conclusion, the rotary valve aerosol delivery system provided higher amounts of drug particles to the test lungs compared to the micropump system. The advantages of these methods were that the humidity in the ventilation circuit did not affect the aerosol particles in the spacer. Further optimisation is required to improve aerosol deposition in the test lungs. The article has also a short section of recent patents relevant to aerosol delivery.

  13. Factors Influencing Continuous Breath Signal in Intubated and Mechanically-Ventilated Intensive Care Unit Patients Measured by an Electronic Nose

    PubMed Central

    Leopold, Jan Hendrik; Abu-Hanna, Ameen; Colombo, Camilla; Sterk, Peter J.; Schultz, Marcus J.; Bos, Lieuwe D. J.

    2016-01-01

    Introduction: Continuous breath analysis by electronic nose (eNose) technology in the intensive care unit (ICU) may be useful in monitoring (patho) physiological changes. However, the application of breath monitoring in a non-controlled clinical setting introduces noise into the data. We hypothesized that the sensor signal is influenced by: (1) humidity in the side-stream; (2) patient-ventilator disconnections and the nebulization of medication; and (3) changes in ventilator settings and the amount of exhaled CO2. We aimed to explore whether the aforementioned factors introduce noise into the signal, and discuss several approaches to reduce this noise. Methods: Study in mechanically-ventilated ICU patients. Exhaled breath was monitored using a continuous eNose with metal oxide sensors. Linear (mixed) models were used to study hypothesized associations. Results: In total, 1251 h of eNose data were collected. First, the initial 15 min of the signal was discarded. There was a negative association between humidity and Sensor 1 (Fixed-effect β: −0.05 ± 0.002) and a positive association with Sensors 2–4 (Fixed-effect β: 0.12 ± 0.001); the signal was corrected for this noise. Outliers were most likely due to noise and therefore removed. Sensor values were positively associated with end-tidal CO2, tidal volume and the pressure variables. The signal was corrected for changes in these ventilator variables after which the associations disappeared. Conclusion: Variations in humidity, ventilator disconnections, nebulization of medication and changes of ventilator settings indeed influenced exhaled breath signals measured in ventilated patients by continuous eNose analysis. We discussed several approaches to reduce the effects of these noise inducing variables. PMID:27556467

  14. Noninvasive mechanical ventilation with average volume assured pressure support (AVAPS) in patients with chronic obstructive pulmonary disease and hypercapnic encephalopathy

    PubMed Central

    2013-01-01

    Background Non-invasive mechanical ventilation (NIV) in patients with acute respiratory failure has been traditionally determined based on clinical assessment and changes in blood gases, with NIV support pressures manually adjusted by an operator. Bilevel positive airway pressure-spontaneous/timed (BiPAP S/T) with average volume assured pressure support (AVAPS) uses a fixed tidal volume that automatically adjusts to a patient’s needs. Our study assessed the use of BiPAP S/T with AVAPS in patients with chronic obstructive pulmonary disease (COPD) and hypercapnic encephalopathy as compared to BiPAP S/T alone, upon immediate arrival in the Emergency-ICU. Methods We carried out a prospective interventional match-controlled study in Guayaquil, Ecuador. A total of 22 patients were analyzed. Eleven with COPD exacerbations and hypercapnic encephalopathy with a Glasgow Coma Scale (GCS) <10 and a pH of 7.25-7.35 were assigned to receive NIV via BiPAP S/T with AVAPS. Eleven patients were selected as paired controls for the initial group by physicians who were unfamiliar with our study, and these patients were administered BiPAP S/T. Arterial blood gases, GCS, vital signs, and ventilatory parameters were then measured and compared between the two groups. Results We observed statistically significant differences in favor of the BiPAP S/T + AVAPS group in GCS (P = .00001), pCO2 (P = .03) and maximum inspiratory positive airway pressure (IPAP) (P = .005), among others. However, no significant differences in terms of length of stay or days on NIV were observed. Conclusions BiPAP S/T with AVAPS facilitates rapid recovery of consciousness when compared to traditional BiPAP S/T in patients with chronic obstructive pulmonary disease and hypercapnic encephalopathy. Trial registration Current Controlled Trials application ref is ISRCTN05135218 PMID:23497021

  15. The effects of positive expiratory pressure on isovolume flow and dynamic hyperinflation in patients receiving mechanical ventilation.

    PubMed

    Gay, P C; Rodarte, J R; Hubmayr, R D

    1989-03-01

    The use of continuous positive airway pressure (CPAP) or positive end-expiratory pressure (PEEP) has been advocated by some to assist in the weaning process of patients receiving mechanical ventilation for respiratory failure. The efficacy of this technique and its effect on respiratory system mechanics are not well understood. The theoretical advantage of CPAP or PEEP during the weaning process can be obliterated if excessive dynamic hyperinflation is induced. A key determinant of the individual response to this proposed weaning technique is the recognition of the presence or absence of expiratory flow limitation. We studied the effect of progressively increased levels of applied PEEP on isovolume expiratory flow and end-expiratory lung volume in seven patients during controlled mechanical ventilation. In the absence of expiratory flow limitation, passive expiratory flow decreased and end-expiratory lung volume increased when any level of PEEP was applied. In contrast, flow-limited patients did not demonstrate a change in isovolume expiratory flow or end-expiratory lung volume until the applied PEEP reduced the driving pressure for expiratory flow below a critical value. All patients demonstrated dynamic hyperinflation during controlled ventilation as evident by the existence of intrinsic PEEP. The nominal value of applied PEEP that caused a reduction in isovolume expiratory flow was unrelated to the initial level of intrinsic PEEP. The clinical implications of these findings with respect to CPAP therapy during weaning from mechanical ventilation are discussed.

  16. Evaluation of a Mapleson D CPAP system for weaning of mechanical ventilation in pediatric patients

    PubMed Central

    Palomero-Rodríguez, Miguel Angel; de Arteaga, Héctor Chozas; Báez, Yolanda Laporta; de Vicente Sánchez, Jesús; Carretero, Pascual Sanabria; Conde, Pilar Sánchez; Pérez Ferrer, Antonio

    2016-01-01

    Background: Over the last years, we have used a flow-inflating bag circuit with a nasotracheal or nasopharyngeal tube as an interface to deliver effective CPAP support in infants (“Mapleson D CPAP system”). The primary goal of this study was to assess the usefulness of the “Mapleson D CPAP system” for weaning of mechanical ventilation (MV) in infants who received MV over 24 h. Materials and Methods: All infants who received MV for more than 24 h in the last year were enrolled in the study. Demographic data included age, gender, weight, and admission diagnosis. Heart rate, respiratory rate, blood pressure, and oxygen saturation were measured during MV, 2 h after the nasotracheal Mapleson D CPAP system and 2 h after extubation. Patients were classified into two groups: patients MV more than 48 h, and patients with MV fewer than 48 h. P < 0.05 was considered statistically significant. Results: A total of 50 children were enrolled in the study, with a median age was 34 ± 45 months (range, 1–59 months) and median weight was 11.98 ± 9.31 kg (range, 1–48 kg). Median duration of MV was 480 h (range, 2–570). There were no significant differences in PaO2, PaCO2, and pH among MV, 2 h after the nasotracheal Mapleson D CPAP system and 2 h after extubation and spontaneous ventilation with the nasopharyngeal Mapleson D CPAP system or with nasal prongs. The overall extubation failure rate was 26% (n = 13). Weight and age were significantly associated with extubation failure (P < 0.05). Conclusions: The Mapleson D CPAP system, in our opinion, is a useful and safe alternative to more complex and expensive noninvasive CPAP and BiPAP weaning from MV in infants. PMID:27625446

  17. How Mechanical Ventilation Measurement, Cutoff and Duration Affect Rapid Shallow Breathing Index Accuracy: A Randomized Trial

    PubMed Central

    Goncalves, Elaine Cristina; Lago, Alessandra Fabiane; Silva, Elaine Caetano; de Almeida, Marcelo Barros; Basile-Filho, Anibal; Gastaldi, Ada Clarice

    2017-01-01

    Background Decreased accuracy of the rapid shallow breathing index (RSBI) can stem from 1) the method used to obtain this index, 2) duration of mechanical ventilation (MV), and 3) the established cutoff point. The objective was to evaluate the values of RSBI determined by three different methods, using distinct MV times and cutoff points. Methods This prospective study included 40 subjects. Before extubation, three different methods were employed to measure RSBI: pressure support ventilator (PSV) (PSV = 5 - 8 cm H2O; positive end-expiratory pressure (PEEP) = 5 cm H2O) (RSBI_MIN), automatic tube compensation (ATC) (PSV = 0, PEEP = 5 cm H2O, and 100% tube compensation) (RSBI_ATC), and disconnected MV (RSBI_SP). The results were analyzed according to the MV period (less than or over 72 h) and to the outcome of extubation (< 72 h, successful and failed; > 72 h successful and failed). The accuracy of each method was determined at different cutoff points (105, 78, and 50 cycles/min/L). Results The RSBI_MIN, RSBI_ATC, and RSBI_SP values in the group < 72 h were 38 ± 18, 45 ± 26 and 55 ± 22; in the group > 72 h, RSBI_SP value was higher than those of RSBI_ATC and RSBI_MIN (78 ± 29, 51 ± 19 and 39 ± 14) (P < 0.001). For patients with MV > 72 h who failed in removing MV, the RSBI_SP was higher (93 ± 28, 58 ± 18 and 41 ± 10) (P < 0.000), with greater accuracy at cutoff of 78. Conclusion RSBI_SP associated with cutoff point < 78 cycles/min/L seems to be the best strategy to identify failed extubation in subjects with MV for over 72 h. PMID:28270888

  18. Influence of mechanical ventilation and sepsis on redox balance in diaphragm, myocardium, limb muscles, and lungs.

    PubMed

    Chacon-Cabrera, Alba; Rojas, Yeny; Martínez-Caro, Leticia; Vila-Ubach, Monica; Nin, Nicolas; Ferruelo, Antonio; Esteban, Andrés; Lorente, José A; Barreiro, Esther

    2014-12-01

    Mechanical ventilation (MV), using high tidal volumes (V(T)), causes lung (ventilator-induced lung injury [VILI]) and distant organ injury. Additionally, sepsis is characterized by increased oxidative stress. We tested whether MV is associated with enhanced oxidative stress in sepsis, the commonest underlying condition in clinical acute lung injury. Protein carbonylation and nitration, antioxidants, and inflammation (immunoblotting) were evaluated in diaphragm, gastrocnemius, soleus, myocardium, and lungs of nonseptic and septic (cecal ligation and puncture 24 hours before MV) rats undergoing MV (n = 7 per group) for 150 minutes using 3 different strategies (low V(T) [V(T) = 9 mL/kg], moderate V(T) [V(T) = 15 mL/kg], and high V(T) [V(T) = 25 mL/kg]) and in nonventilated control animals. Compared with nonventilated control animals, in septic and nonseptic rodents (1) diaphragms, limb muscles, and myocardium of high-V(T) rats exhibited a decrease in protein oxidation and nitration levels, (2) antioxidant levels followed a specific fiber-type distribution in slow- and fast-twitch muscles, (3) tumor necrosis factor α (TNF-α) levels were higher in respiratory and limb muscles, whereas no differences were observed in myocardium, and (4) in lungs, protein oxidation was increased, antioxidants were rather decreased, and TNF-α remained unmodified. In this model of VILI, oxidative stress does not occur in distant organs or skeletal muscles of rodents after several hours of MV with moderate-to-high V(T), whereas protein oxidation levels were increased in the lungs of the animals. Inflammatory events were moderately expressed in skeletal muscles and lungs of the MV rats. Concomitant sepsis did not strongly affect the MV-induced effects on muscles, myocardium, or lungs in the rodents.

  19. Lung Function and Organ Dysfunctions in 178 Patients Requiring Mechanical Ventilation During The 2009 Influenza A (H1N1) Pandemic

    PubMed Central

    2011-01-01

    Introduction Most cases of the 2009 influenza A (H1N1) infection are self-limited, but occasionally the disease evolves to a severe condition needing hospitalization. Here we describe the evolution of the respiratory compromise, ventilatory management and laboratory variables of patients with diffuse viral pneumonitis caused by pandemic 2009 influenza A (H1N1) admitted to the ICU. Method This was a multicenter, prospective inception cohort study including adult patients with acute respiratory failure requiring mechanical ventilation (MV) admitted to 20 ICUs in Argentina between June and September of 2009 during the influenza A (H1N1) pandemic. In a standard case-report form, we collected epidemiological characteristics, results of real-time reverse-transcriptase--polymerase-chain-reaction viral diagnostic tests, oxygenation variables, acid-base status, respiratory mechanics, ventilation management and laboratory tests. Variables were recorded on ICU admission and at days 3, 7 and 10. Results During the study period 178 patients with diffuse viral pneumonitis requiring MV were admitted. They were 44 ± 15 years of age, with Acute Physiology And Chronic Health Evaluation II (APACHE II) scores of 18 ± 7, and most frequent comorbidities were obesity (26%), previous respiratory disease (24%) and immunosuppression (16%). Non-invasive ventilation (NIV) was applied in 49 (28%) patients on admission, but 94% were later intubated. Acute respiratory distress syndrome (ARDS) was present throughout the entire ICU stay in the whole group (mean PaO2/FIO2 170 ± 25). Tidal-volumes used were 7.8 to 8.1 ml/kg (ideal body weight), plateau pressures always remained < 30 cmH2O, without differences between survivors and non-survivors; and mean positive end-expiratory pressure (PEEP) levels used were between 8 to 12 cm H2O. Rescue therapies, like recruitment maneuvers (8 to 35%), prone positioning (12 to 24%) and tracheal gas insufflation (3%) were frequently applied. At all time points

  20. “Not Being Able to Talk was Horrid”: A Descriptive, Correlational Study of Communication During Mechanical Ventilation

    PubMed Central

    Guttormson, Jill L.; Bremer, Karin Lindstrom; Jones, Rachel M.

    2015-01-01

    Objectives The purpose of this study was to describe the patient experience of communication during mechanical ventilation Research Methodology This descriptive study is a secondary analysis of data collected to study the relationship between sedation and the MV patients' recall of the ICU. Interviews, conducted after extubation, included the Intensive Care Experience Questionnaire. Data were analyzed with Spearman correlation coefficients (rs) and content analysis. Setting Participants were recruited from a medical-surgical intensive care unit in the Midwest United States. Results Participants (n=31) with a mean age of 65 ± 11.9 were on the ventilator a median of 5 days. Inability to communicate needs was associated with helplessness (rs = .43). While perceived lack of information received was associated with not feeling in control (rs =.41) and helplessness (rs =.41). Ineffective communication negatively impacted satisfaction with care. Participants expressed frustration with failed communication and a lack of information received. They believed receipt of information helped them cope and desired a better system of communication during mechanical ventilation. Conclusion Communication effectiveness impacts patients' sense of safety and well-being during mechanical ventilation. Greater emphasis needs to be placed on the development and integration of communication strategies into critical care nursing practice. PMID:25579081

  1. Development of a Novel Alarm System to Improve Adaptation to Non-invasive Ventilation in Patients With High Cervical Spinal Cord Injury

    PubMed Central

    2016-01-01

    In this case report, we want to introduce a successful way of applying non-invasive ventilation (NIV) with a full face mask in patients with high cervical spinal cord injury through a novel alarm system for communication. A 57-year-old man was diagnosed with C3 American Spinal Injury Association impairment scale (AIS) B. We applied NIV for treatment of hypercapnia. Because of mouth opening during sleep, a full face mask was the only way to use NIV. However, he could not take off the mask by himself, and this situation caused great fear. To solve this problem, we designed a novel alarm system. The best intended motion of the patient was neck rotation. Sensing was performed by a balloon sensor placed under the head of the patient. A beep sound was generated whenever the pressure was above the threshold, and more than three consecutive beeps within 3,000 ms created a loud alarm for caregivers. PMID:27847728

  2. Initiation of non-invasive ventilation in amyotrophic lateral sclerosis and clinical practice guidelines: Single-centre, retrospective, descriptive study in a national reference centre.

    PubMed

    Georges, Marjolaine; Golmard, Jean-Louis; Llontop, Claudia; Shoukri, Amr; Salachas, François; Similowski, Thomas; Morelot-Panzini, Capucine; Gonzalez-Bermejo, Jésus

    2017-02-01

    In amyotrophic lateral sclerosis (ALS), respiratory muscle weakness leads to respiratory failure. Non-invasive ventilation (NIV) maintains adequate ventilation in ALS patients. NIV alleviates symptoms and improves survival. In 2006, French guidelines established criteria for NIV initiation based on limited evidence. Their impact on clinical practice remains unknown. Our objective was to describe NIV initiation practices of the main French ALS tertiary referral centre with respect to guidelines. In this retrospective descriptive study, 624 patients followed in a single national reference centre began NIV between 2005 and 2013. We analysed criteria used to initiate NIV, including symptoms, PaCO2, forced vital capacity, maximal inspiratory pressures and time spent with SpO2 <90% at night. At NIV initiation, 90% of patients were symptomatic. Median PaCO2 was 48 mmHg. The main criterion to initiate NIV was 'symptoms' followed by 'hypercapnia' in 42% and 34% of cases, respectively. NIV was initiated on functional parameters in only 5% of cases. Guidelines were followed in 81% of cases. In conclusion, despite compliance with French guidelines, the majority of patients are treated at the stage of symptomatic daytime hypoventilation, which suggests that NIV is initiated late in the course of ALS. Whether this practice could be improved by changing guidelines or increasing respiratory-dedicated resources remains to be determined.

  3. Mild hypothermia attenuates changes in respiratory system mechanics and modifies cytokine concentration in bronchoalveolar lavage fluid during low lung volume ventilation.

    PubMed

    Dostál, P; Senkeřík, M; Pařízková, R; Bareš, D; Zivný, P; Zivná, H; Cerný, V

    2010-01-01

    Hypothermia was shown to attenuate ventilator-induced lung injury due to large tidal volumes. It is unclear if the protective effect of hypothermia is maintained under less injurious mechanical ventilation in animals without previous lung injury. Tracheostomized rats were randomly allocated to non-ventilated group (group C) or ventilated groups of normothermia (group N) and mild hypothermia (group H). After two hours of mechanical ventilation with inspiratory fraction of oxygen 1.0, respiratory rate 60 min(-1), tidal volume 10 ml x kg(-1), positive end-expiratory pressure (PEEP) 2 cm H2O or immediately after tracheostomy in non-ventilated animals inspiratory pressures were recorded, rats were sacrificed, pressure-volume (PV) curve of respiratory system constructed, bronchoalveolar lavage (BAL) fluid and aortic blood samples obtained. Group N animals exhibited a higher rise in peak inspiratory pressures in comparison to group H animals. Shift of the PV curve to right, higher total protein and interleukin-6 levels in BAL fluid were observed in normothermia animals in comparison with hypothermia animals and non-ventilated controls. Tumor necrosis factor-alpha was lower in the hypothermia group in comparison with normothermia and non-ventilated groups. Mild hypothermia attenuated changes in respiratory system mechanics and modified cytokine concentration in bronchoalveolar lavage fluid during low lung volume ventilation in animals without previous lung injury.

  4. The effect of an upper respiratory care program on incidence of ventilator-associated pneumonia in mechanically ventilated patients hospitalized in intensive care units

    PubMed Central

    Bakhtiari, Soheila; Yazdannik, Ahmadreza; Abbasi, Saeid; Bahrami, Nasim

    2015-01-01

    Background: Ventilator-associated pneumonia (VAP) is a common side effect in patients with an endotracheal tube. This study aimed to evaluate the effect of an upper respiratory care program on the incidence of VAP in mechanically ventilated patients. Materials and Methods: In this clinical trial, 62 patients with endotracheal tube were selected and randomly allocated to intervention or control group. In the intervention group, an upper respiratory care program was performed and in the control group, routine care was done. Modified Clinical Pulmonary Infection Questionnaire was completed before, and on the third, fourth, and fifth day after intervention. Data were analyzed by repeated measure analysis of variance (ANOVA), chi-square, and independent t-test through SPSS 13. Results: The results of this study showed that until the fourth day, the incidence of VAP was similar in both intervention and control groups (P > 0.05), but on the fifth day, the incidence of VAP in the intervention group was significantly lower than in the control group (P < 0.05). Conclusions: The results of this study showed that in patients with an endotracheal tube, an upper respiratory care program may reduce the incidence of VAP. Therefore, in order to prevent VAP, nurses are recommended to perform this upper respiratory care program. PMID:26120336

  5. Preoxygenation using invasive ventilator in volume control mode in patients with emergency intubation can shorten the time of preoxygenation and improve the quality of preoxygenation

    PubMed Central

    Wang, Hai; Sun, Jiang-Li; Bai, Zheng-Hai; Wang, Xiao-Bo; Zhang, Zheng-Liang; Pei, Hong-Hong

    2016-01-01

    Abstract Preoxygenation can rapidly improve oxygenation and enhance the security of endotracheal intubation, so it is very essential before endotracheal intubation. The conventional preoxygenation method self-inflating bag (SIB) is not very effective in case of emergency. So our study aims to find a more effective method of preoxygenation in a critical situation. We retrospectively analyzed data of 105 patients in this study. A total of 49 patients with preoxygenation with invasive ventilator in volume control mode (VCM) and 56 patients with preoxygenation with SIB were included. No significant differences were detected in the baseline data of the 2 groups (P > 0.05). Time of preoxygenation (95%) was 174 (168–180) seconds in group VCM and 205 (199–212) seconds in group SIB (P < 0.05), and multifactor linear regression showed that its main risk factors were the methods of preoxygenation and PO2 before preoxygenation (P < 0.05). Immediate SPO2 after preoxygenation was 91 (89–92)% in group VCM and 85 (83–86)% in group SIB (P < 0.05). Total time of preoxygenation and intubation was 266 (252–280) seconds in group VCM and 318 (298–338) seconds in group SIB (P < 0.05). The 24-hour and overall survival rate in group SIB were lower than in group VCM (P > 0.05). Cox regression showed that SaO2 at 5 minutes after intubation was the major risk factor for the survival rate. Invasive ventilator with volume control mode can shorten the time of preoxygenation and improve the quality of preoxygenation in patients with emergency intubation and may be a better method of preoxygenation in a critical situation. PMID:27749553

  6. Mechanical ventilation during anaesthesia: challenges and opportunities for investigating the respiration-related cardiovascular oscillations.

    PubMed

    Beda, Alessandro; Carvalho, Nadja C; Güldner, Andreas; Koch, Thea; de Abreu, Marcelo Gama

    2011-08-01

    The vast majority of the available literature regarding cardiovascular oscillations refers to spontaneously breathing subjects. Only a few studies investigated cardiovascular oscillations, and especially respiration-related ones (RCVO), during intermittent positive pressure mechanical ventilation (IPPV) under anaesthesia. Only a handful considered assisted IPPV, in which spontaneous breathing activity is supported, rather than replaced as in controlled IPPV. In this paper, we review the current understanding of RCVO physiology during IPPV, from literature retrieved through PubMed website. In particular, we describe how during controlled IPPV under anaesthesia respiratory sinus arrhythmia appears to be generated by non-neural mechano-electric feedback in the heart (indirectly influenced by tonic sympathetic regulation of vascular tone and heart contractility) and not by phasic vagal modulation of central origin and/or baroreflex mechanisms. Furthermore, assisted IPPV differs from controlled IPPV in terms of RCVO, reintroducing significant central respiratory vagal modulation of respiratory sinus arrhythmia. This evidence indicates against applying to IPPV interpretative paradigms of RCVO derived from spontaneously breathing subjects, and against considering together IPPV and spontaneously breathing subjects for RCVO-based risk assessment. Finally, we highlight the opportunities that IPPV offers for future investigations of RCVO genesis and interactions, and we indicate several possibilities for clinical applications of RCVO during IPPV.

  7. Plasma-derived human C1-esterase inhibitor does not prevent mechanical ventilation-induced pulmonary complement activation in a rat model of Streptococcus pneumoniae pneumonia.

    PubMed

    de Beer, F M; Aslami, H; Hoeksma, J; van Mierlo, G; Wouters, D; Zeerleder, S; Roelofs, J J T H; Juffermans, N P; Schultz, M J; Lagrand, W K

    2014-11-01

    Mechanical ventilation has the potential to cause lung injury, and the role of complement activation herein is uncertain. We hypothesized that inhibition of the complement cascade by administration of plasma-derived human C1-esterase inhibitor (C1-INH) prevents ventilation-induced pulmonary complement activation, and as such attenuates lung inflammation and lung injury in a rat model of Streptococcus pneumoniae pneumonia. Forty hours after intratracheal challenge with S. pneumoniae causing pneumonia rats were subjected to ventilation with lower tidal volumes and positive end-expiratory pressure (PEEP) or high tidal volumes without PEEP, after an intravenous bolus of C1-INH (200 U/kg) or placebo (saline). After 4 h of ventilation blood, broncho-alveolar lavage fluid and lung tissue were collected. Non-ventilated rats with S. pneumoniae pneumonia served as controls. While ventilation with lower tidal volumes and PEEP slightly amplified pneumonia-induced complement activation in the lungs, ventilation with higher tidal volumes without PEEP augmented local complement activation more strongly. Systemic pre-treatment with C1-INH, however, failed to alter ventilation-induced complement activation with both ventilation strategies. In accordance, lung inflammation and lung injury were not affected by pre-treatment with C1-INH, neither in rats ventilated with lower tidal volumes and PEEP, nor rats ventilated with high tidal volumes without PEEP. Ventilation augments pulmonary complement activation in a rat model of S. pneumoniae pneumonia. Systemic administration of C1-INH, however, does not attenuate ventilation-induced complement activation, lung inflammation, and lung injury.

  8. Clinical factors associated with weaning failure in patients requiring prolonged mechanical ventilation

    PubMed Central

    Shin, Hong-Joon; Chang, Jin-Sun; Ahn, Seong; Kim, Tae-Ok; Park, Cheol-Kyu; Lim, Jung-Hwan; Oh, In-Jae; Kim, Yu-Il; Lim, Sung-Chul; Kim, Young-Chul

    2017-01-01

    Background For patients requiring prolonged mechanical ventilation (PMV), weaning is difficult and mortality is very high. PMV has been defined recently, by consensus, as constituting ≥21 consecutive days of mechanical ventilation (MV) for ≥6 hours per day. This study aimed to evaluate the clinical factors predicting weaning failure in patients undergoing PMV in medical intensive care unit (ICU). Methods We retrospectively reviewed the clinical and laboratory characteristics of 127 patients who received MV for more than 21 days in the medical ICU at Chonnam National University Hospital in South Korea between January 2005 and December 2014. Patients who underwent surgery or experienced trauma were excluded from this study. Results Among the 127 patients requiring PMV, 41 (32.3%) were successfully weaned from MV. The median age of the weaning failure group was higher than that of the weaning success group (74.0 vs. 70.0 years; P=0.003). The proportion of male patients was 58.5% in the weaning success group and 72.1% in the weaning failure group, respectively. The most common reasons for ICU admission were respiratory causes (66.1%) followed by cardiovascular causes (16.5%) in both groups. ICU mortality and in-hospital mortality rates were 55.1% and 55.9%, respectively. In the multivariate analysis, respiratory causes of ICU admission [odds ratio (OR), 3.98; 95% confidence interval (CI), 1.29–12.30; P=0.016] and a high sequential organ failure assessment (SOFA) score on day 21 of MV (OR, 1.47; 95% CI, 1.17–1.85; P=0.001) were significantly associated with weaning failure in patients requiring PMV. The area under the receiver operating characteristic (ROC) curve of the SOFA score on day 21 of MV for predicting weaning failure was 0.77 (95% CI, 0.67–0.87; P=0.000). Conclusions Respiratory causes of ICU admission and a high SOFA score on day 21 of MV could be predictive of weaning failure in patients requiring PMV. PMID:28203417

  9. Opioid Analgesia in Mechanically Ventilated Children: Results from the multicenter MOTIF study

    PubMed Central

    Anand, Kanwaljeet J. S.; Clark, Amy E.; Willson, Douglas F.; Berger, John; Meert, Kathleen L.; Zimmerman, Jerry J.; Harrison, Rick; Carcillo, Joseph A.; Newth, Christopher J. L.; Bisping, Stephanie; Holubkov, Richard; Dean, J. Michael; Nicholson, Carol E.

    2013-01-01

    Objective To examine the clinical factors associated with increased opioid dose among mechanically ventilated children in the Pediatric Intensive Care Unit (PICU). Design Prospective, observational study with 100% accrual of eligible patients. Setting Seven PICUs from tertiary-care children’s hospitals in the Collaborative Pediatric Critical Care Research Network. Patients 419 children treated with morphine or fentanyl infusions. Interventions None Measurements and Main Results Data on opioid use, concomitant therapy, demographic and explanatory variables were collected. Significant variability occurred in clinical practices, with up to 100-fold differences in baseline opioid doses, average daily or total doses, or peak infusion rates. Opioid exposure for 7 or 14 days required doubling of the daily opioid dose in 16% patients (95%CI: 12–19%) and 20% patients (95%CI: 16–24%) respectively. Among patients receiving opioids for longer than 3 days (n=225), this occurred in 28% (95%CI 22–33%) and 35% (95%CI 29–41%) by 7 or 14 days respectively. Doubling of the opioid dose was more likely to occur following opioid infusions for 7 days or longer (OR 7.9, 95%CI 4.3–14.3; p<0.001) or co-therapy with midazolam (OR 5.6, 95%CI 2.4–12.9; p<0.001), and it was less likely to occur if morphine was used as the primary opioid (vs. fentanyl) (OR 0.48, 95%CI 0.25–0.92; p=0.03), for patients receiving higher initial doses (OR 0.96, 95%CI 0.95–0.98; p<0.001), or if patients had prior PICU admissions (OR 0.37, 95%CI 0.15–0.89, p=0.03). Conclusions Mechanically ventilated children require increasing opioid doses, often associated with prolonged opioid exposure or the need for additional sedation. Efforts to reduce prolonged opioid exposure and clinical practice variation may prevent the complications of opioid therapy. PMID:23132396

  10. Effect of Positive End-Expiratory Pressure on Central Venous Pressure in Patients under Mechanical Ventilation

    PubMed Central

    Shojaee, Majid; Sabzghabaei, Anita; Alimohammadi, Hossein; Derakhshanfar, Hojjat; Amini, Afshin; Esmailzadeh, Bahareh

    2017-01-01

    Introduction: Finding the probable governing pattern of PEEP and CVP changes is an area of interest for in-charge physicians and researchers. Therefore, the present study was designed with the aim of evaluating the relationship between the mentioned pressures. Methods: In this quasi-experimental study, patients under mechanical ventilation were evaluated with the aim of assessing the effect of PEEP change on CVP. Non-trauma patients, over 18 years of age, who were under mechanical ventilation and had stable hemodynamics, with inserted CV line were entered. After gathering demographic data, patients underwent 0, 5, and 10 cmH2O PEEPs and the respective CVPs of the mentioned points were recorded. The relationship of CVP and PEEP in different cut points were measured using SPSS 21.0 statistical software. Results: 60 patients with the mean age of 73.95 ± 11.58 years were evaluated (68.3% male). The most frequent cause of ICU admission was sepsis with 45.0%. 5 cmH2O increase in PEEP led to 2.47 ± 1.53 mean difference in CVP level. If the PEEP baseline is 0 at the time of 5 cmH2O increase, it leads to a higher raise in CVP compared to when the baseline is 5 cmH2O (2.47 ± 1.53 vs. 1.57 ± 1.07; p = 0.039). The relationship between CVP and 5 cmH2O (p = 0.279), and 10 cmH2O (p = 0.292) PEEP changes were not dependent on the baseline level of CVP. Conclusion: The findings of this study revealed the direct relationship between PEEP and CVP. Approximately, a 5 cmH2O increase in PEEP will be associated with about 2.5 cmH2O raise in CVP. When applying a 5 cmH2O PEEP increase, if the baseline PEEP is 0, it leads to a significantly higher raise in CVP compared to when it is 5 cmH2O (2.5 vs. 1.6). It seems that sex, history of cardiac failure, baseline CVP level, and hypertension do not have a significant effect in this regard. PMID:28286808

  11. Comparison between a clinical diagnosis method and the surveillance technique of the Center for Disease Control and Prevention for identification of mechanical ventilator-associated pneumonia

    PubMed Central

    Waltrick, Renata; Possamai, Dimitri Sauter; de Aguiar, Fernanda Perito; Dadam, Micheli; de Souza, Valmir João; Ramos, Lucas Rocker; Laurett, Renata da Silva; Fujiwara, Kênia; Caldeira, Milton; Koenig, Álvaro; Westphal, Glauco Adrieno

    2015-01-01

    Objective >To evaluate the agreement between a new epidemiological surveillance method of the Center for Disease Control and Prevention and the clinical pulmonary infection score for mechanical ventilator-associated pneumonia detection. Methods This was a prospective cohort study that evaluated patients in the intensive care units of two hospitals who were intubated for more than 48 hours between August 2013 and June 2014. Patients were evaluated daily by physical therapist using the clinical pulmonary infection score. A nurse independently applied the new surveillance method proposed by the Center for Disease Control and Prevention. The diagnostic agreement between the methods was evaluated. A clinical pulmonary infection score of ≥ 7 indicated a clinical diagnosis of mechanical ventilator-associated pneumonia, and the association of a clinical pulmonary infection score ≥ 7 with an isolated semiquantitative culture consisting of ≥ 104 colony-forming units indicated a definitive diagnosis. Results Of the 801 patients admitted to the intensive care units, 198 required mechanical ventilation. Of these, 168 were intubated for more than 48 hours. A total of 18 (10.7%) cases of mechanical ventilation-associated infectious conditions were identified, 14 (8.3%) of which exhibited possible or probable mechanical ventilatorassociated pneumonia, which represented 35% (14/38) of mechanical ventilator-associated pneumonia cases. The Center for Disease Control and Prevention method identified cases of mechanical ventilator-associated pneumonia with a sensitivity of 0.37, specificity of 1.0, positive predictive value of 1.0, and negative predictive value of 0.84. The differences resulted in discrepancies in the mechanical ventilator-associated pneumonia incidence density (CDC, 5.2/1000 days of mechanical ventilation; clinical pulmonary infection score ≥ 7, 13.1/1000 days of mechanical ventilation). Conclusion The Center for Disease Control and Prevention method failed to

  12. Developing a neonatal unit ventilation protocol for the preterm baby.

    PubMed

    Sant'Anna, G M; Keszler, M

    2012-12-01

    Mechanical ventilation is a resource-intensive complex medical intervention associated with high morbidity. Considerable practice style variation exists in most hospitals and is not only confusing for parents, but the lack of consistently high standard of optimal ventilation deprives some infants of the benefits of state-of-the-art care. Developing a unit protocol for mechanical ventilation requires exhaustive research, inclusion of all stake-holders, thoughtful protocol development and careful implementation after a thorough educational process, followed by monitoring. A protocol for respiratory support should be comprehensive, addressing respiratory support in the delivery room, the use of non-invasive support, intubation criteria, surfactant administration, specific ventilation modes and settings, criteria for escalating therapy, weaning protocols, extubation criteria, and post-extubation management. Evidence favors the use of non-invasive support as first line treatment, progressing to assist/control or pressure support ventilation combined with volume guarantee, if needed, and high-frequency ventilation only for specific indications. The open lung strategy is crucial to lung-protective ventilation.

  13. Management of Ventilatory Insufficiency in Neuromuscular Patients Using Mechanical Ventilator Supported by the Korean Government.

    PubMed

    Kang, Seong-Woong; Choi, Won Ah; Cho, Han Eol; Lee, Jang Woo; Park, Jung Hyun

    2016-06-01

    Since 2001, financial support has been provided for all patients with neuromuscular disease (NMD) who require ventilatory support due to the paralysis of respiratory muscles in Korea. The purpose of this study was to identify ventilator usage status and appropriateness in these patients. We included 992 subjects with rare and incurable NMD registered for ventilator rental fee support. From 21 February 2011 to 17 January 2013, ventilator usage information, regular follow-up observation, and symptoms of chronic hypoventilation were surveyed by phone. Home visits were conducted for patients judged by an expert medical team to require medical examination. Abnormal ventilatory status was assessed by respiratory evaluation. Chronic respiratory insufficiency symptoms were reported by 169 of 992 subjects (17%), while 565 subjects (57%) did not receive regular respiratory evaluation. Ventilatory status was abnormal in 102 of 343 home-visit subjects (29.7%). Although 556 subjects (56%) reported 24-hour ventilator use, only 458 (46%) had an oxygen saturation monitoring device, and 305 (31%) performed an airstacking exercise. A management system that integrates ventilator usage monitoring, counselling and advice, and home visits for patients who receive ventilator support could improve the efficiency of the ventilator support project.

  14. Management of Ventilatory Insufficiency in Neuromuscular Patients Using Mechanical Ventilator Supported by the Korean Government

    PubMed Central

    2016-01-01

    Since 2001, financial support has been provided for all patients with neuromuscular disease (NMD) who require ventilatory support due to the paralysis of respiratory muscles in Korea. The purpose of this study was to identify ventilator usage status and appropriateness in these patients. We included 992 subjects with rare and incurable NMD registered for ventilator rental fee support. From 21 February 2011 to 17 January 2013, ventilator usage information, regular follow-up observation, and symptoms of chronic hypoventilation were surveyed by phone. Home visits were conducted for patients judged by an expert medical team to require medical examination. Abnormal ventilatory status was assessed by respiratory evaluation. Chronic respiratory insufficiency symptoms were reported by 169 of 992 subjects (17%), while 565 subjects (57%) did not receive regular respiratory evaluation. Ventilatory status was abnormal in 102 of 343 home-visit subjects (29.7%). Although 556 subjects (56%) reported 24-hour ventilator use, only 458 (46%) had an oxygen saturation monitoring device, and 305 (31%) performed an airstacking exercise. A management system that integrates ventilator usage monitoring, counselling and advice, and home visits for patients who receive ventilator support could improve the efficiency of the ventilator support project. PMID:27247509

  15. Pursuing excellence: development of an oral hygiene protocol for mechanically ventilated patients.

    PubMed

    Browne, Jennifer A; Evans, Diana; Christmas, Lauren A; Rodriguez, Maria

    2011-01-01

    Oral hygiene in seriously ill patients is a nursing responsibility. Oral hygiene regimens in conjunction with standardized ventilator-associated pneumonia "bundles" reduce the incidence of pneumonia, length of stay, and associated costs in critical care. Following strict adherence to the recommended ventilator-associated pneumonia bundle, the ventilator-associated pneumonia rate at the Northeast Baptist Hospital intensive care units has remained 0% for 36 months. Oral care in this patient population, however, has remained vague based on ritual and nurse preference. This article describes the development of an oral care protocol based on best evidence, providing a rationale for standardization of oral hygiene and the plan for surveillance and updating.

  16. Intermittent noninvasive ventilation at San José Hospital in Chile: report of a German donation.

    PubMed

    Arellano Maric, M P; Roldán Toledo, R; Huttmann, S E; Storre, J H; Windisch, W

    2015-03-01

    Home mechanical ventilation is currently expanding in Chile, but its application along the country is hindered by financial and geographical reasons. In 2006 the San José Hospital in Santiago de Chile developed a non-invasive ventilation (NIV) center as a strategy to overcome the limitations of ventilator availability from public resources. Since then, this center provides intermittent diurnal sessions of NIV to patients with chronic hypercapnic respiratory failure. In 2013, a collaboratory work between the Chilean doctors, the German Interdisciplinary Society of Home Mechanical Ventilation (DIGAB = Deutsche Interdisziplinäre Gesellschaft für Außerklinische Beatmung) and the German non-invasive (NIV) home care provider "Heinen und Löwenstein" organized a donation of 100 second-hand ventilators (BiPAP Synchrony; Respironics, USA) including masks and tubing systems, which were provided by Heinen und Löwenstein. The ventilator devices arrived in Santiago in January 2014. Since then, the following initiatives have been launched: 1) the establishment of a domiciliary mechanical ventilation program independent of governmental founding, 2) NIV setting-titration, 3) renewal of ventilators at the hospital's intermittent NIV unit. Future goals are the establishment of a rehabilitation unit with concomitant NIV therapy and a clinical research program. Therefore, the German donation of ventilators and equipment has a reported impact on the development of NIV in Chile.

  17. Pain assessment during blood collection from sedated and mechanically ventilated children

    PubMed Central

    Dantas, Layra Viviane Rodrigues Pinto; Dantas, Thiago Silveira Pinto; Santana-Filho, Valter Joviniano; Azevedo-Santos, Isabela Freire; DeSantana, Josimari Melo

    2016-01-01

    Objective This study assessed pain and observed physiological parameters in sedated and mechanically ventilated children during a routine procedure. Methods This observational study was performed in a pediatric intensive care unit. Thirty-five children between 1 month and 12 years of age were assessed before, during, and five minutes after an arterial blood collection for gas analysis (painful procedure). Face, Legs, Activity, Cry and Consolability scale was used to assess pain. In addition, patients' heart rate, respiratory rate, peripheral saturation of oxygen and blood pressure (diastolic and systolic) were recorded. COMFORT-B scale was applied before the pain and physiological parameter assessments to verify sedation level of the subjects. Results There was an increase in Face, Legs, Activity, Cry and Consolability score (p = 0.0001) during painful stimuli. There was an increase in heart rate (p = 0.03), respiratory rate (p = 0.001) and diastolic blood pressure (p = 0.006) due to pain caused by the routine procedure. Conclusions This study suggests that assessments of pain using standard scales, such as Face, Legs, Activity, Cry and Consolability score, and other physiological parameters should be consistently executed to optimize pain management in pediatric intensive care units. PMID:27096676

  18. Mechanical ventilation triggers abnormal mitochondrial dynamics and morphology in the diaphragm.

    PubMed

    Picard, Martin; Azuelos, Ilan; Jung, Boris; Giordano, Christian; Matecki, Stefan; Hussain, Sabah; White, Kathryn; Li, Tong; Liang, Feng; Benedetti, Andrea; Gentil, Benoit J; Burelle, Yan; Petrof, Basil J

    2015-05-01

    The diaphragm is a unique skeletal muscle designed to be rhythmically active throughout life, such that its sustained inactivation by the medical intervention of mechanical ventilation (MV) represents an unanticipated physiological state in evolutionary terms. Within a short period after initiating MV, the diaphragm develops muscle atrophy, damage, and diminished strength, and many of these features appear to arise from mitochondrial dysfunction. Notably, in response to metabolic perturbations, mitochondria fuse, divide, and interact with neighboring organelles to remodel their shape and functional properties-a process collectively known as mitochondrial dynamics. Using a quantitative electron microscopy approach, here we show that diaphragm contractile inactivity induced by 6 h of MV in mice leads to fragmentation of intermyofibrillar (IMF) but not subsarcolemmal (SS) mitochondria. Furthermore, physical interactions between adjacent organellar membranes were less abundant in IMF mitochondria during MV. The profusion proteins Mfn2 and OPA1 were unchanged, whereas abundance and activation status of the profission protein Drp1 were increased in the diaphragm following MV. Overall, our results suggest that mitochondrial morphological abnormalities characterized by excessive fission-fragmentation represent early events during MV, which could potentially contribute to the rapid onset of mitochondrial dysfunction, maladaptive signaling, and associated contractile dysfunction of the diaphragm.

  19. Home mechanical ventilation in the aftermath of the Hanshin-Awaji earthquake disaster.

    PubMed

    Shimada, S; Funato, M

    1995-12-01

    Children who were dependent upon home mechanical ventilation (HMV), suffered in various ways from the disastrous Hanshin-Awaji earthquake disaster. The earthquake abruptly cut the supplies of water, gas and electricity, causing intense anxiety for those families. Through loss of the respirator function, some of them experienced an unexpected catastrophe. In the disaster area, there were children who were dependent upon HMV (19 cases) and children who were preparing for HMV in hospitals (nine cases). Information was gathered from questionnaires about the disaster, communication and correspondence with families. None of the 28 cases died or were injured. Nineteen cases had a variety of problems. In eight cases, respiratory support problems were acute. Nevertheless, all of them survived the crisis successfully even in the midst of such a catastrophic situation. An organization of HMV children's families, called the Baku-Baku Club, helped families with HMV problems by supplying water, food, oxygen and compressed air cylinders among other things. Additional outside batteries for portable respirators are essential equipment for HMV, especially for emergencies. A manual for clarifying the system for support in the Baku-Baku Club and a registration system for public medical service should be established in preparation for such a crisis.

  20. What is the proper approach to liberating the weak from mechanical ventilation?

    PubMed

    Brochard, Laurent; Thille, Arnaud W

    2009-10-01

    The general issue of weaning can be viewed as composed of three different groups of patients. First, simple or easy weaning, represents 60% to 70% of patients whose first trial of spontaneous breathing is successful. The main objective of the weaning process is to detect weaning readiness as early as possible, which is best achieved using a systematic approach. The percentage of patients in this group in a given intensive care unit represents the pretest probability of weaning. A second group is made of patients who experience failure of the first spontaneous breathing trial and in whom up to 7 days from the first trial may be required to achieve weaning. This group represents 20% to 25% of patients who undergo weaning from mechanical ventilation. Muscle weakness contributes to the prolongation of weaning in many of these patients. The last group is made of patients who are characterized by a prolonged or very difficult weaning process (about 5% to 15% of patients undergoing weaning). Muscle weakness is likely to be a major contributing factor. Early use of spontaneous breathing, well-controlled use of sedation, and early mobilization may help in reducing muscle weakness and hasten the weaning process. The postextubation period may be particularly at risk in these patients. More research is needed to guide clinicians regarding the best ventilatory management.

  1. Fluctuations of inspired concentrations of nitric oxide and nitrogen dioxide during mechanical ventilation.

    PubMed

    Kuhlen; Busch; Max; Reyle-Hahn; Falke; Rossaint

    1999-01-01

    BACKGROUND: Nitric oxide (NO) is a very reactive agent with potentially toxic oxidation products such as nitrogen dioxide (NO2). Therefore, during NO inhalation a constant inspired concentration and accurate measurement of NO and NO2 concentrations are essential. The objective of this study was to test the NO concentrations at various positions along the inspiratory limb of the breathing circuit using a recently developed system to administer NO in phase with inspiratory flow during mechanical ventilation (Servo 300 NO-A, Siemens, Sweden). Furthermore, we tested whether an active heating system would interfere with inspired NO concentrations. RESULTS: A sharp decline in the NO concentration was found between the respirator's inspiratory outlet and more distal points along the inspiratory limb of the circuit. This finding was most evident when an active heating system was mounted between those points. CONCLUSIONS: The concentrations of NO and NO2 should be measured as near to the patient as possible, as significant fluctuations of these concentrations might be found along the inspiratory limb of the respiratory circuit especially when an active heating system is used.

  2. Fluctuations of inspired concentrations of nitric oxide and nitrogen dioxide during mechanical ventilation

    PubMed Central

    Kuhlen, Ralf; Busch, Thilo; Max, Martin; Reyle-Hahn, Matthias; Falke, Konrad J; Rossaint, Rolf

    1999-01-01

    Background: Nitric oxide (NO) is a very reactive agent with potentially toxic oxidation products such as nitrogen dioxide (NO2). Therefore, during NO inhalation a constant inspired concentration and accurate measurement of NO and NO2 concentrations are essential. The objective of this study was to test the NO concentrations at various positions along the inspiratory limb of the breathing circuit using a recently developed system to administer NO in phase with inspiratory flow during mechanical ventilation (Servo 300 NO-A, Siemens, Sweden). Furthermore, we tested whether an active heating system would interfere with inspired NO concentrations. Results: A sharp decline in the NO concentration was found between the respirator's inspiratory outlet and more distal points along the inspiratory limb of the circuit. This finding was most evident when an active heating system was mounted between those points. Conclusions: The concentrations of NO and NO2 should be measured as near to the patient as possible, as significant fluctuations of these concentrations might be found along the inspiratory limb of the respiratory circuit especially when an active heating system is used. PMID:11056715

  3. Usefulness of open lung biopsy in mechanically ventilated patients with undiagnosed diffuse pulmonary infiltrates: influence of comorbidities and organ dysfunction

    PubMed Central

    Lim, Seong Yong; Suh, Gee Young; Choi, Jae Chol; Koh, Won Jung; Lim, Si Young; Han, Joungho; Lee, Kyung Soo; Shim, Young Mog; Chung, Man Pyo; Kim, Hojoong; Kwon, O Jung

    2007-01-01

    Background The purpose of this study was to evaluate the clinical usefulness of open lung biopsy (OLB) in patients undergoing mechanical ventilation for diffuse pulmonary infiltrates of unknown etiology. Methods This was a 10-year retrospective study in a 10-bed medical intensive care unit. The medical records of 36 ventilator-dependent patients who underwent OLB for the diagnosis of unknown pulmonary infiltrates from 1994 to 2004 were reviewed retrospectively. Data analyzed included demographic data, Charlson age–comorbidity score, number of organ dysfunctions, Acute Physiology and Chronic Health Evaluation (APACHE) II, Simplified Acute Physiology Score (SAPS) II, Sequential Organ Failure Assessment (SOFA) score, ventilation variables, and radiological patterns. Diagnostic yield, effect on subsequent treatment changes, and complications of OLB were also assessed. Results A specific clinico-pathologic diagnosis was obtained for 31 patients (86%). The most common diagnoses were interstitial pneumonia (n = 17, including 8 acute interstitial pneumonia) and viral pneumonia (n = 4). Therapeutic modifications were made in 64% of patients. Patients who received OLB less than 1 week after initiation of mechanical ventilation were more likely to survive (63% versus 11%; P = 0.018). There were no major complications associated with the procedure. Factors independently associated with survival were the Charlson age-comorbidity score, number of organ dysfunction and the PaO2/FiO2 ratio on the day of the OLB. Conclusion OLB can provide a specific diagnosis in many ventilator-dependent patients with undiagnosed pulmonary infiltrate. Early OLB seems to be useful in critically ill patients with isolated respiratory failure. PMID:17725820

  4. Air Distribution Effectiveness for Residential Mechanical Ventilation: Simulation and Comparison of Normalized Exposures

    SciTech Connect

    Petithuguenin, T.D.P.; Sherman, M.H.

    2009-05-01

    The purpose of ventilation is to dilute indoor contaminants that an occupant is exposed to. Even when providing the same nominal rate of outdoor air, different ventilation systems may distribute air in different ways, affecting occupants' exposure to household contaminants. Exposure ultimately depends on the home being considered, on source disposition and strength, on occupants' behavior, on the ventilation strategy, and on operation of forced air heating and cooling systems. In any multi-zone environment dilution rates and source strengths may be different in every zone and change in time, resulting in exposure being tied to occupancy patterns.This paper will report on simulations that compare ventilation systems by assessing their impact on exposure by examining common house geometries, contaminant generation profiles, and occupancy scenarios. These simulations take into account the unsteady, occupancy-tied aspect of ventilation such as bathroom and kitchen exhaust fans. As most US homes have central HVAC systems, the simulation results will be used to make appropriate recommendations and adjustments for distribution and mixing to residential ventilation standards such as ASHRAE Standard 62.2.This paper will report on work being done to model multizone airflow systems that are unsteady and elaborate the concept of distribution matrix. It will examine several metrics for evaluating the effect of air distribution on exposure to pollutants, based on previous work by Sherman et al. (2006).

  5. Tracheostomy and mechanical ventilation weaning in children affected by respiratory virus according to a weaning protocol in a pediatric intensive care unit in Argentina: an observational restrospective trial

    PubMed Central

    2011-01-01

    We describe difficult weaning after prolonged mechanical ventilation in three tracheostomized children affected by respiratory virus infection. Although the spontaneous breathing trials were successful, the patients failed all extubations. Therefore a tracheostomy was performed and the weaning plan was begun. The strategy for weaning was the decrease of ventilation support combining pressure control ventilation (PCV) with increasing periods of continuous positive airway pressure + pressure support ventilation (CPAP + PSV) and then CPAP + PSV with increasing intervals of T-piece. They presented acute respiratory distress syndrome on admission with high requirements of mechanical ventilation (MV). Intervening factors in the capabilities and loads of the respiratory system were considered and optimized. Th