Update on Middle Ear Barotrauma after Hyperbaric Oxygen Therapy—Insights on Pathophysiology

PubMed Central

Lima, Marco Antônio Rios; Farage, Luciano; Cury, Maria Cristina Lancia; Bahamad, Fayez

2014-01-01

Introduction Middle ear barotrauma is the most common side effect of hyperbaric oxygen therapy. Knowledge and understanding of its pathophysiology are crucial for an accurate diagnosis and proper decision making about treatment and prevention. Objective Describe up-to-date information on pathophysiology of middle ear barotrauma after hyperbaric oxygen therapy considering the physiology of pressure variation of the middle ear. Data Synthesis Middle ear barotrauma occurs especially during the compression phase of hyperbaric oxygen therapy. The hyperoxic environment in hyperbaric oxygen therapy leads to ventilatory dysfunction of the eustachian tube, especially in monoplace chambers, where the patients are pressurized with 100% O2, favoring middle ear barotrauma. Conclusion The eustachian tube, the tympanic cavity, and mastoid work together in a neural controlled feedback system in which various mechanisms concur for middle ear pressure regulation. PMID:25992091

Hyperbaric oxygen therapy for traumatic brain injury

PubMed Central

2011-01-01

Traumatic brain injury (TBI) is a major public health issue. The complexity of TBI has precluded the use of effective therapies. Hyperbaric oxygen therapy (HBOT) has been shown to be neuroprotective in multiple neurological disorders, but its efficacy in the management of TBI remains controversial. This review focuses on HBOT applications within the context of experimental and clinical TBI. We also discuss its potential neuroprotective mechanisms. Early or delayed multiple sessions of low atmospheric pressure HBOT can reduce intracranial pressure, improve mortality, as well as promote neurobehavioral recovery. The complimentary, synergistic actions of HBOT include improved tissue oxygenation and cellular metabolism, anti-apoptotic, and anti-inflammatory mechanisms. Thus HBOT may serve as a promising neuroprotective strategy that when combined with other therapeutic targets for TBI patients which could improve long-term outcomes. PMID:22146562

Hyperbaric Oxygen Therapy - An Adjunct to Optimal Combat Trauma Management

DTIC Science & Technology

2004-09-01

the morbidity and mortality of necrotizing fasciitis and gas gangrene, where treatment with HBO2 results in clinical improvement even when standard...04. Hirn, M. (1993). "Hyperbaric oxygen in the treatment of gas gangrene and perineal necrotizing fasciitis . A clinical and experimental study...34Hyperbaric oxygen therapy for necrotizing fasciitis reduces mortality and the need for debridements." Surgery 108(5): 847-50. Rosenthal, E., A. Benderly

The Effect of Hyperbaric Oxygen on Symptoms after Mild Traumatic Brain Injury

DTIC Science & Technology

2012-11-20

Proceedings of the 2nd International Symposium on Hy- perbaric Oxygenation for Cerebral Palsy and the Brain-Injured Child. J.T. Joiner (ed). Best...Krages, K.P., and Helfand, M. (2003). Hyperbaric oxygen therapy for brain injury, cerebral palsy , and stroke: summary, in: AHRQ Evidence Report...prospective, randomized clinical trial to compare the effect of hyperbaric to normobaric hyper- oxia on cerebral metabolism, intracranial pressure, and oxygen

The place of hyperbaric oxygen therapy and ozone therapy in sudden hearing loss.

PubMed

Ergun Taşdöven, Gülin; Derin, Alper Tunga; Yaprak, Neslihan; Özçağlar, Hasan Ümit

It is difficult to evaluate the effect of drugs clinically used for idiopathic sudden sensorineural hearing loss, mainly because its underlying mechanism remains unknown. This study assessed the efficacy of hyperbaric oxygen therapy or ozone therapy in the treatment of idiopathic sudden sensorineural hearing loss, when either therapy was included with steroid treatment. A retrospective analysis examined 106 patients with idiopathic sudden sensorineural hearing loss seen between January 2010 and June 2012. Those with an identified etiology were excluded. The patients were divided into three treatment groups: oral steroid only (n=65), oral steroid+hyperbaric oxygen (n=26), and oral steroid+ozone (n=17). Treatment success was assessed using Siegel criteria and mean gains using pre- and post-treatment audiograms. The highest response rate to treatment was observed in the oral steroid+ozone therapy group (82.4%), followed by the oral steroid+hyperbaric oxygen (61.5%), and oral steroid groups (50.8%). There were no significant differences in the response to treatment between the oral steroid and oral steroid+hyperbaric oxygen groups (p<0.355). The oral steroid+ozone group showed a significantly higher response rate to treatment than the oral steroid group (p=0.019). There were no significant differences between the oral steroid+hyperbaric oxygen and oral steroid+ozone groups (p=0.146). The efficiency of steroid treatment in patients with severe hearing loss was low. It was statistically ascertained that adding hyperbaric oxygen or ozone therapy to the treatment contributed significantly to treatment success. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Treatment of radiation cystitis with hyperbaric oxygen

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schoenrock, G.J.; Cianci, P.

A patient with severe radiation cystitis resistant to current therapy was treated with hyperbaric oxygen to facilitate closure of a vesicocutaneous fistula. In addition to the fistula healing, her symptoms of radiation cystitis have not recurred for over a year and a half.

Hyperbaric oxygen in skeletal muscle of rats submitted to total acute left hindlimb ischemia: A research report.

PubMed

da Silva, Luis Gustavo Campos; Dalio, Marcelo Bellini; Joviliano, Edwaldo Edner; Feres, Omar; Piccinato, Carlos Eli

2015-01-01

Determine the effect of hyperbaric oxygen treatment in skeletal muscle of rats submitted to total acute left hindlimb ischemia. An experimental study was designed using 48 Wistar rats divided into four groups (n = 12): Control; Ischemia (I)--total hindlimb ischemia for 270 minutes; Hyperbaric oxygen treatment during ischemia (HBO2)--total hindlimb ischemia for 270 minutes and hyperbaric oxygen during the first 90 minutes; Pre-treatment with hyperbaric oxygen (PHBO2)--90 minutes of hyperbaric oxygen treatment before total hindlimb ischemia for 270 minutes. Skeletal muscle injury was evaluated by measuring levels of aspartate aminotransferase (AST), lactate dehydrogenase (LDH), total creatine phosphokinase (CPK); muscular malondialdehyde (MDA), muscular glycogen, and serum ischemia-modified albumin (IMA). AST was significantly higher in I, HBO2 and PHBO2 compared with control (P = .001). There was no difference in LDH. CPK was significantly higher in I, HBO2 and PHBO2, compared with control (p = .014). MDA was significantly higher in PHBO2, compared with other groups (p = .042). Glycogen was significantly decreased in I, HBO2 and PHBO2, compared with control (p < .001). Hyperbaric oxygen treatment in acute total hindlimb ischemia exerted no protective effect on muscle injury, regardless of time of application. When applied prior to installation of total ischemia, hyperbaric oxygen treatment aggravated muscle injury.

Effect of hyperbaric oxygen therapy combined with autologous platelet concentrate applied in rabbit fibula fraction healing

PubMed Central

Neves, Paulo César Fagundes; de Campos Vieira Abib, Simone; Neves, Rogério Fagundes; Pircchio, Oronzo; Saad, Karen Ruggeri; Saad, Paulo Fernandes; Simões, Ricardo Santos; Moreira, Marcia Bento; de Souza Laurino, Cristiano Frota

2013-01-01

OBJECTIVES: The purpose is to study the effects of hyperbaric oxygen therapy and autologous platelet concentrates in healing the fibula bone of rabbits after induced fractures. METHODS: A total of 128 male New Zealand albino rabbits, between 6–8 months old, were subjected to a total osteotomy of the proximal portion of the right fibula. After surgery, the animals were divided into four groups (n = 32 each): control group, in which animals were subjected to osteotomy; autologous platelet concentrate group, in which animals were subjected to osteotomy and autologous platelet concentrate applied at the fracture site; hyperbaric oxygen group, in which animals were subjected to osteotomy and 9 consecutive daily hyperbaric oxygen therapy sessions; and autologous platelet concentrate and hyperbaric oxygen group, in which animals were subjected to osteotomy, autologous platelet concentrate applied at the fracture site, and 9 consecutive daily hyperbaric oxygen therapy sessions. Each group was divided into 4 subgroups according to a pre-determined euthanasia time points: 2, 4, 6, and 8 weeks postoperative. After euthanasia at a specific time point, the fibula containing the osseous callus was prepared histologically and stained with hematoxylin and eosin or picrosirius red. RESULTS: Autologous platelet concentrates and hyperbaric oxygen therapy, applied together or separately, increased the rate of bone healing compared with the control group. CONCLUSION: Hyperbaric oxygen therapy and autologous platelet concentrate combined increased the rate of bone healing in this experimental model. PMID:24141841

Systematic review of hyperbaric oxygen therapy for the treatment of radiation-induced skin necrosis.

PubMed

Borab, Zachary; Mirmanesh, Michael D; Gantz, Madeleine; Cusano, Alessandro; Pu, Lee L Q

2017-04-01

Every year, 1.2 million cancer patients receive radiation therapy in the United States. Late radiation tissue injury occurs in an estimated 5-15% of these patients. Tissue injury can include skin necrosis, which can lead to chronic nonhealing wounds. Despite many treatments available to help heal skin necrosis such as hyperbaric oxygen therapy, no clinical guidelines exist and evidence is lacking. The purpose of this review is to identify and comprehensively summarize studies published to date to evaluate the effectiveness of hyperbaric oxygen therapy for the treatment of radiation-induced skin necrosis. Adhering to PRISMA guidelines, a systematic review of currently published articles was performed, evaluating the use of hyperbaric oxygen to treat skin necrosis. Eight articles were identified, including one observational cohort, five case series, and two case reports. The articles describe changes in symptoms and alteration in wound healing of radiation-induced skin necrosis after treatment with hyperbaric oxygen therapy. Hyperbaric oxygen therapy is a safe intervention with promising outcomes; however, additional evidence is needed to endorse its application as a relevant therapy in the treatment of radiation-induced skin necrosis. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

The effect of hyperbaric oxygen treatment on early regeneration of sensory axons after nerve crush in the rat.

PubMed

Bajrović, Fajko F; Sketelj, Janez; Jug, Marko; Gril, Iztok; Mekjavić, Igor B

2002-09-01

Abstract The effect of hyperbaric oxygen treatment (HBO) on sensory axon regeneration was examined in the rat. The sciatic nerve was crushed in both legs. In addition, the distal stump of the sural nerve on one side was made acellular and its blood perfusion was compromised by freezing and thawing. Two experimental groups received hyperbaric exposures (2.5 ATA) to either compressed air (pO2 = 0.5 ATA) or 100% oxygen (pO2 = 2.5 ATA) 90 minutes per day for 6 days. Sensory axon regeneration in the sural nerve was thereafter assessed by the nerve pinch test and immunohistochemical reaction to neurofilament. HBO treatment increased the distances reached by the fastest regenerating sensory axons by about 15% in the distal nerve segments with preserved and with compromised blood perfusion. There was no significant difference between the rats treated with different oxygen tensions. The total number of regenerated axons in the distal sural nerve segments after a simple crush injury was not affected, whereas in the nerve segments with compromised blood perfusion treated by the higher pO2, the axon number was about 30% lower than that in the control group. It is concluded that the beneficial effect of HBO on sensory axon regeneration is not dose-dependent between 0.5 and 2.5 ATA pO2. Although the exposure to 2.5 ATA of pO2 moderately enhanced early regeneration of the fastest sensory axons, it decreased the number of regenerating axons in the injured nerves with compromised blood perfusion of the distal nerve stump.

Nonhealing Wounds Caused by Brown Spider Bites: Application of Hyperbaric Oxygen Therapy.

PubMed

Hadanny, Amir; Fishlev, Gregory; Bechor, Yair; Meir, Oshra; Efrati, Shai

2016-12-01

Bites by Loxosceles spiders (also known as recluse spiders or brown spiders) can cause necrotic ulcerations of various sizes and dimensions. The current standard of care for brown spider bites includes analgesics, ice, compression, elevation, antihistamines, and surgical debridement. Hyperbaric oxygen therapy (HBOT) in the treatment of brown spider bites has been administered in the early stage of ulceration, or 2 to 6 days after the bite. Unfortunately, the diagnosis of spider bite-related ulcers is often delayed and weeks or months may elapse before HBOT is considered. To evaluate the effect of HBOT on nonhealing wounds caused by brown spider bites in the late, chronic, nonhealing stage. Analysis of 3 patients with brown spider-bite healing wounds treated at The Sagol Center for Hyperbaric Medicine and Research in Israel. Patients presented 2 to 3 months after failure of other therapies including topical dressings, antibiotics, and corticosteroids. All patients were treated with daily 2 ATA (atmospheres absolute) with 100% oxygen HBOT sessions. All 3 patients were previously healthy without any chronic disease. Their ages were 30, 42, and 73 years. They were treated once daily for 13, 17, and 31 sessions, respectively. The wounds of all 3 patients healed, and there was no need for additional surgical intervention. There were no significant adverse events in any of the patients. Microvascular injury related to brown spider bites may culminate in ischemic nonhealing wounds even in a relatively young, healthy population. Hyperbaric oxygen therapy should be considered as a valuable therapeutic tool even months after the bite.

[Effects of combined natural hirudin and hyperbaric oxygen therapy on survival of transplanted random-pattern skin flap in rats].

PubMed

Cai, Jieyun; Lin, Bojie; Pan, Xinyuan; Cui, Jia; Pradhan, Rohan; Yin, Guoqian

2018-04-01

To investigate the effect of natural hirudin combined with hyperbaric oxygen therapy on the survival of transplanted random-pattern skin flap in rats. A random-pattern skin flap in size of 10.0 cm×2.5 cm was elevated on the dorsum of 72 Sprague Dawley rats. Then the 72 rats were randomly divided into 4 groups ( n =18) according to the therapy method. At immediate and within 4 days after operation, the rats were treated with normal saline injection in control group, normal saline injection combined with hyperbaric oxygen treatment in hyperbaric oxygen group, the natural hirudin injection in natural hirudin group, and the natural hirudin injection combined with hyperbaric oxygen treatment in combined group. The flap survival was observed after operation, and survival rate was evaluated at 6 days after operation. The skin samples were collected for histological analysis, microvessel density (MVD) measurement, and evaluation of tumor necrosis factor α (TNF-α) expression level by the immunohistochemical staining at 2 and 4 days after operation. Partial necrosis occurred in each group after operation, and the flap in combined group had the best survival. The survival rate of flap was significantly higher in hyperbaric oxygen group, natural hirudin group, and combined group than that in control group, and in combined group than in hyperbaric oxygen group and natural hirudin group ( P <0.05). There was no significant difference between hyperbaric oxygen group and natural hirudin group ( P >0.05). At 2 days, more microvascular structure was observed in hyperbaric oxygen group, natural hirudin group, and combined group in comparison with control group; while plenty of inflammatory cells infiltration in all groups. At 4 days, the hyperbaric oxygen group, natural hirudin group, and the combined group still showed more angiogenesis. Meanwhile, there was still infiltration of inflammatory cells in control group, inflammatory cells in the other groups were significantly

Non-convulsive status epilepticus in a patient with carbon-monoxide poisoning treated with hyperbaric oxygen therapy.

PubMed

Marziali, Simone; Di Giuliano, Francesca; Picchi, Eliseo; Natoli, Silvia; Leonardis, Carlo; Leonardis, Francesca; Garaci, Francesco; Floris, Roberto

2016-12-01

The presentation of carbon monoxide poisoning is non-specific and highly variable. Hyperbaric oxygen therapy is used for the treatment of this condition. Various reports show the occurrence of self-limiting seizures after carbon monoxide poisoning and as a consequence of hyperbaric oxygen therapy. Contrary to the seizures, status epilepticus has been rarely observed in these conditions. The exact pathophysiology underlying seizures and status epilepticus associated with carbon monoxide poisoning and hyperbaric oxygen therapy is not really clear, and some elements appear to be common to both conditions. We describe a case of non-convulsive status epilepticus in a patient with carbon monoxide poisoning treated with hyperbaric oxygen therapy. The mechanism, MRI findings and implications are discussed. © The Author(s) 2016.

Osmotic phenomena in application for hyperbaric oxygen treatment.

PubMed

Babchin, A; Levich, E; Melamed M D, Y; Sivashinsky, G

2011-03-01

Hyperbaric oxygen (HBO) treatment defines the medical procedure when the patient inhales pure oxygen at elevated pressure conditions. Many diseases and all injuries are associated with a lack of oxygen in tissues, known as hypoxia. HBO provides an effective method for fast oxygen delivery in medical practice. The exact mechanism of the oxygen transport under HBO conditions is not fully identified. The objective of this article is to extend the colloid and surface science basis for the oxygen transport in HBO conditions beyond the molecular diffusion transport mechanism. At a pressure in the hyperbaric chamber of two atmospheres, the partial pressure of oxygen in the blood plasma increases 10 times. The sharp increase of oxygen concentration in the blood plasma creates a considerable concentration gradient between the oxygen dissolved in the plasma and in the tissue. The concentration gradient of oxygen as a non-electrolyte solute causes an osmotic flow of blood plasma with dissolved oxygen. In other words, the molecular diffusion transport of oxygen is supplemented by the convective diffusion raised due to the osmotic flow, accelerating the oxygen delivery from blood to tissue. A non steady state equation for non-electrolyte osmosis is solved asymptotically. The solution clearly demonstrates two modes of osmotic flow: normal osmosis, directed from lower to higher solute concentrations, and anomalous osmosis, directed from higher to lower solute concentrations. The fast delivery of oxygen from blood to tissue is explained on the basis of the strong molecular interaction between the oxygen and the tissue, causing an influx of oxygen into the tissue by convective diffusion in the anomalous osmosis process. The transport of the second gas, nitrogen, dissolved in the blood plasma, is also taken into the consideration. As the patient does not inhale nitrogen during HBO treatment, but exhales it along with oxygen and carbon dioxide, the concentration of nitrogen in blood

Hyperbaric oxygen therapy for children with autism spectrum disorder.

PubMed

Sakulchit, Teeranai; Ladish, Chris; Goldman, Ran D

2017-06-01

Question As autism spectrum disorder (ASD) is a multifactorial condition, with genetic and environmental risk factors contributing to children's unique presentation and symptom severity, a range of treatments have been suggested. Parents of children with ASD in my clinic are asking me about alternative therapies to improve their children's condition. One of those therapies is hyperbaric oxygen therapy (HBOT); commercial advertisement in the past has suggested good results with this approach. Should I recommend the use of HBOT for children with ASD? Answer Hyperbaric oxygen therapy provides a higher concentration of oxygen delivered in a chamber or tube containing higher than sea level atmospheric pressure. Case series and randomized controlled trials show no evidence to support the benefit of HBOT for children with ASD. Only 1 randomized controlled trial reported effectiveness of this treatment, and those results have yet to be repeated. Copyright© the College of Family Physicians of Canada.

Hyperbaric Oxygen Environment Can Enhance Brain Activity and Multitasking Performance

PubMed Central

Vadas, Dor; Kalichman, Leonid; Hadanny, Amir; Efrati, Shai

2017-01-01

Background: The Brain uses 20% of the total oxygen supply consumed by the entire body. Even though, <10% of the brain is active at any given time, it utilizes almost all the oxygen delivered. In order to perform complex tasks or more than one task (multitasking), the oxygen supply is shifted from one brain region to another, via blood perfusion modulation. The aim of the present study was to evaluate whether a hyperbaric oxygen (HBO) environment, with increased oxygen supply to the brain, will enhance the performance of complex and/or multiple activities. Methods: A prospective, double-blind randomized control, crossover trial including 22 healthy volunteers. Participants were asked to perform a cognitive task, a motor task and a simultaneous cognitive-motor task (multitasking). Participants were randomized to perform the tasks in two environments: (a) normobaric air (1 ATA 21% oxygen) (b) HBO (2 ATA 100% oxygen). Two weeks later participants were crossed to the alternative environment. Blinding of the normobaric environment was achieved in the same chamber with masks on while hyperbaric sensation was simulated by increasing pressure in the first minute and gradually decreasing to normobaric environment prior to tasks performance. Results: Compared to the performance at normobaric conditions, both cognitive and motor single tasks scores were significantly enhanced by HBO environment (p < 0.001 for both). Multitasking performance was also significantly enhanced in HBO environment (p = 0.006 for the cognitive part and p = 0.02 for the motor part). Conclusions: The improvement in performance of both single and multi-tasking while in an HBO environment supports the hypothesis which according to, oxygen is indeed a rate limiting factor for brain activity. Hyperbaric oxygenation can serve as an environment for brain performance. Further studies are needed to evaluate the optimal oxygen levels for maximal brain performance. PMID:29021747

Hyperbaric Oxygen Environment Can Enhance Brain Activity and Multitasking Performance.

PubMed

Vadas, Dor; Kalichman, Leonid; Hadanny, Amir; Efrati, Shai

2017-01-01

Background: The Brain uses 20% of the total oxygen supply consumed by the entire body. Even though, <10% of the brain is active at any given time, it utilizes almost all the oxygen delivered. In order to perform complex tasks or more than one task (multitasking), the oxygen supply is shifted from one brain region to another, via blood perfusion modulation. The aim of the present study was to evaluate whether a hyperbaric oxygen (HBO) environment, with increased oxygen supply to the brain, will enhance the performance of complex and/or multiple activities. Methods: A prospective, double-blind randomized control, crossover trial including 22 healthy volunteers. Participants were asked to perform a cognitive task, a motor task and a simultaneous cognitive-motor task (multitasking). Participants were randomized to perform the tasks in two environments: (a) normobaric air (1 ATA 21% oxygen) (b) HBO (2 ATA 100% oxygen). Two weeks later participants were crossed to the alternative environment. Blinding of the normobaric environment was achieved in the same chamber with masks on while hyperbaric sensation was simulated by increasing pressure in the first minute and gradually decreasing to normobaric environment prior to tasks performance. Results: Compared to the performance at normobaric conditions, both cognitive and motor single tasks scores were significantly enhanced by HBO environment ( p < 0.001 for both). Multitasking performance was also significantly enhanced in HBO environment ( p = 0.006 for the cognitive part and p = 0.02 for the motor part). Conclusions: The improvement in performance of both single and multi-tasking while in an HBO environment supports the hypothesis which according to, oxygen is indeed a rate limiting factor for brain activity. Hyperbaric oxygenation can serve as an environment for brain performance. Further studies are needed to evaluate the optimal oxygen levels for maximal brain performance.

Rapid analysis of hyperbaric oxygen therapy registry data for reimbursement purposes: Technical communication.

PubMed

Fife, Caroline E; Gelly, Helen; Walker, David; Eckert, Kristen Allison

2016-01-01

To explain how Hyperbaric Oxygen Therapy Registry (HBOTR) data of the US Wound Registry (USWR) helped establish a fair analysis of the physician work of hyperbaric chamber supervision for reimbursement purposes. We queried HBOTR data from January 1, 2013, to December 31, 2013, on patient comorbidities and medications as well as the number of hyperbaric oxygen (HBO₂) therapy treatments supervised per physician per day from all hyperbaric facilities participating in the USWR that had been using the electronic medical record (EHR) for more than six months and had passed data completeness checks. Among 11,240 patients at the 87 facilities included, the mean number of comorbidities and medications was 10 and 12, respectively. The mean number of HBO₂ treatments supervised per physician per day was 3.7 at monoplace facilities and 5.4 at multiplace facilities. Following analysis of these data by the RUC, the reimbursement rate of chamber supervision was decreased to $112.06. Patients undergoing HBO₂ therapy generally suffer from multiple, serious comorbidities and require multiple medications, which increase the risk of HBO₂ and necessitate the presence of a properly trained hyperbaric physician. The lack of engagement by hyperbaric physicians in registry reporting may result in lack of adequate data being available to counter future challenges to reimbursement.

The Effect of Hyperbaric Oxygen on the Growth of Rhizopus nigricans.

DTIC Science & Technology

1980-12-01

identify by block number) Impression Chamber Medical Mycology Oxygen Therapy (ompression Therapy Mucor Phycomycosis hvp)erbaric Medicine Mucormycosis...rado. 3. Cai rnev, W. J. 1980. The effect of hyperbaric oxygen on the growth of Mucor sp. and Aspergillus fumigLatus. Technical Report FJSRL-TR- 80

Hyperbaric oxygen treatment for Parkinson's disease with severe depression and anxiety: A case report.

PubMed

Xu, Jin-Jin; Yang, Si-Tong; Sha, Ying; Ge, Yuan-Yuan; Wang, Jian-Meng

2018-03-01

Patients with Parkinson's disease (PD) frequently suffer from psychiatric disorders, and treating these symptom whereas managing the motor symptoms associated with PD can be a therapeutic challenge. We report a case of PD patient with severe depression and anxiety that refused to be treated with dopaminagonists or SSRIs, the most common treatments for PD patients suffering from psychiatric symptoms. Parkinson's disease with severe depression and anxiety. This man was treated with hyperbaric oxygen treatment for 30 days. Clinical assessment scores for depression and anxiety, including Unified Parkinson's Disease Rating ScaleI (UPDRS I), UPDRS II, Hanmilton Depression Rating Scale, and Hamiliton Anxiety Rating Scale, were improved following the hyperbaric oxygen treatment. Hyperbaric oxygen treatment may be a potential therapeutic method for PD patient suffering from depression and anxiety. Further research is needed to validate this finding and explore a potential mechanism.

Clinical utility of hyperbaric oxygen therapy in genitourinary medicine

PubMed Central

Gandhi, Jason; Seyam, Omar; Smith, Noel L.; Joshi, Gunjan; Vatsia, Sohrab; Khan, Sardar Ali

2018-01-01

Hyperbaric oxygen therapy (HBOT) is a medical technique which delivers oxygen at ambient pressures to increase the amount of dissolved oxygen in the blood and oxygen distribution to tissues. There are several beneficial properties of HBOT concomitant with elevated oxygen distribution in tissue including anti-inflammation, angiogenesis through vascular endothelial growth factor proliferation, augmented fibroblast activity through fibroblast growth factor proliferation, tissue and wound repair, enhancement of lymphocyte and macrophage activity, increased male testosterone secretion, and bactericidal activity. Given its renown in treating conditions such as decompression sickness and carbon monoxide poisoning, HBOT is making gradual strides for use in genitourinary medicine due to its low risk and likeliness to achieve favorable results. Early success has been observed in the treatment of Fournier's gangrene, radiation cystitis, and interstitial cystitis via the elimination of clinical symptoms such as pain. Further indications that have exhibited positive outcomes despite HBOT's ambiguous mechanism of action include cyclophosphamide hemorrhagic cystitis, emphysematous cystitis, pelvic radiation disease, radiation-induced proctopathy, dystrophic calcification of the prostate, erectile dysfunction secondary to urethroplasty, priapism, abnormal renal morphology, blood testosterone, calcific uremic arteriolopathy, and hidradenitis suppurativa. For other indications, multicenter studies must be conducted to determine HBOT's true efficacy, mechanism of action, risks, and advantages over conventional treatments.

Effects of hyperbaric oxygen on intracranial pressure and cerebral blood flow in experimental cerebral oedema1

PubMed Central

Miller, J. D.; Ledingham, I. McA.; Jennett, W. B.

1970-01-01

Increased intracranial pressure was induced in anaesthetized dogs by application of liquid nitrogen to the dura mater. Intracranial pressure and cerebral blood flow were measured, together with arterial blood pressure and arterial and cerebral venous blood gases. Carbon dioxide was administered intermittently to test the responsiveness of the cerebral circulation, and hyperbaric oxygen was delivered at intervals in a walk-in hyperbaric chamber, pressurized to two atmospheres absolute. Hyperbaric oxygen caused a 30% reduction of intracranial pressure and a 19% reduction of cerebral blood flow in the absence of changes in arterial PCO2 or blood pressure, but only as long as administration of carbon dioxide caused an increase in both intracranial pressure and cerebral blood flow. When carbon dioxide failed to influence intracranial pressure or cerebral blood flow then hyperbaric oxygen had no effect. This unresponsive state was reached at high levels of intracranial pressure. Images PMID:5497875

Variability in hyperbaric oxygen treatment for acute carbon monoxide poisoning.

PubMed

Byrne, Brendan T; Lu, Jenny J; Valento, Matthew; Bryant, Sean M

2012-01-01

In patients with acute carbon monoxide (CO) poisoning, we have noted wide clinical variability in both criteria for hyperbaric oxygen (HBO2) treatment as well as HBO2 treatment regimens. Our aim was to survey Midwest hyperbaric centers for insight into specific criteria and protocols for treating acute CO toxicity with HBO2. Hyperbaric centers were identified from the published list of the Undersea and Hyperbaric Medical Society. Ninety-three centers from nine Midwestern states were contacted via telephone. A standard script was used to minimize surveyor bias. Thirty centers that treat CO poisonings were identified. One did not participate in the study. Nineteen reported a specific level of carboxyhemoglobin (COHb) that served as an independent indication for initiation of HBO2 treatment. Four centers used the COHb level as the exclusive indication for HBO2 treatment. Ten centers relied solely on reported symptoms, while the remaining centers used a combination of symptoms plus COHb levels. There were 19 separate treatment protocols. No uniform practice for either the initiation or implementation of HBO2 therapy for CO poisoning exists among U.S. Midwest hyperbaric centers responding to a survey. We see opportunity for specific targeted educational programs as well as further study.

Effect of hyperbaric oxygenation on carbohydrate metabolism protein synthesis in the myocardium during sustained hypodynamia

NASA Technical Reports Server (NTRS)

Makarov, G. A.

1980-01-01

Glycolysis and the intensity of protein synthesis were studied in 140 white male rats in subcellular fractions of the myocardium during 45 day hypodynamia and hyperbaric oxygenation. Hypodynamia increased: (1) the amount of lactic acids; (2) the amount of pyruvic acid; (3) the lactate/pyruvate coefficient; and (4) the activities of aldolase and lactate dehydrogenase. Hyperbaric oxygenation was found to have a favorable metabolic effect on the animals with hypodynamia.

Hyperbaric oxygen modalities are differentially effective in distinct brain ischemia models

PubMed Central

Ostrowski, Robert P.; Stępień, Katarzyna; Pucko, Emanuela; Matyja, Ewa

2016-01-01

The effectiveness and efficacy of hyperbaric oxygen (HBO) preconditioning and post-treatment modalities have been demonstrated in experimental models of ischemic cerebrovascular diseases, including global brain ischemia, transient focal and permanent focal cerebral ischemia, and experimental neonatal hypoxia-ischemia encephalopathy. In general, early and repetitive post-treatment of HBO appears to create enhanced protection against brain ischemia whereas delayed HBO treatment after transient focal ischemia may even aggravate brain injury. This review advocates the level of injury reduction upon HBO as an important component for translational evaluation of HBO based treatment modalities. The combined preconditioning and HBO post-treatment that would provide synergistic effects is also worth considering. PMID:27826422

Oxygen Delivery from Hyperbarically Loaded Microtanks Extends Cell Viability in Anoxic Environments

PubMed Central

Cook, Colin A.; Hahn, Kathryn C.; Morrissette-McAlmon, Justin B.F.; Grayson, Warren L.

2016-01-01

Oxygen diffusion limitations within nascent tissue engineered (TE) grafts lead to the development of hypoxic regions, cell death, and graft failure. Previous efforts have been made to deliver oxygen within TE scaffolds, including peroxide-doping, perfluorocarbons, and hyperbaric oxygen therapy, to mitigate these effects and help maintain post transplantation cell viability, but these have suffered from significant drawbacks. Here we present a novel approach utilizing polymeric hollow-core microspheres that can be hyperbarically loaded with oxygen and subsequently provide prolonged oxygen delivery. These oxygen carriers are termed, microtanks. With an interest in orthopedic applications, we combined microtanks within polycaprolactone to form solid phase constructs with oxygen delivery capabilities. The mathematical laws governing oxygen delivery from microtank-loaded constructs are developed along with empirical validation. Constructs achieved periods of oxygen delivery out to 6 days, which was shown to prolong the survival of human adipose derived stem cells (hASCs) and human umbilical vein endothelial cells (HUVECs) as well as to enhance their cellular morphology under anoxic conditions. The results of this study suggest the microtank approach may be a feasible means of maintaining cell viability in TE scaffolds during the critical period of vascularization in vivo. PMID:25818444

Hyperbaric oxygen therapy for the prevention of arterial gas embolism in food grade hydrogen peroxide ingestion.

PubMed

Hendriksen, Stephen M; Menth, Nicholas L; Westgard, Bjorn C; Cole, Jon B; Walter, Joseph W; Masters, Thomas C; Logue, Christopher J

2017-05-01

Food grade hydrogen peroxide ingestion is a relatively rare presentation to the emergency department. There are no defined guidelines at this time regarding the treatment of such exposures, and providers may not be familiar with the potential complications associated with high concentration hydrogen peroxide ingestions. In this case series, we describe four patients who consumed 35% hydrogen peroxide, presented to the emergency department, and were treated with hyperbaric oxygen therapy. Two of the four patients were critically ill requiring intubation. All four patients had evidence on CT or ultrasound of venous gas emboli and intubated patients were treated as if they had an arterial gas embolism since an exam could not be followed. After hyperbaric oxygen therapy each patient was discharged from the hospital neurologically intact with no other associated organ injuries related to vascular gas emboli. Hyperbaric oxygen therapy is an effective treatment for patients with vascular gas emboli after high concentration hydrogen peroxide ingestion. It is the treatment of choice for any impending, suspected, or diagnosed arterial gas embolism. Further research is needed to determine which patients with portal venous gas emboli should be treated with hyperbaric oxygen therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

Double-blind trials in hyperbaric medicine: A narrative review on past experiences and considerations in designing sham hyperbaric treatment.

PubMed

Lansdorp, C A; van Hulst, Rob A

2018-06-01

Background Hyperbaric oxygen therapy, which consists of breathing 100% oxygen under a higher atmospheric pressure than normal, is utilized worldwide in the treatment of several diseases. With the growing demand for evidence-based research, hyperbaric oxygen therapy has been criticized for delivering too little high-quality research, mainly in the form of randomized controlled trials. While not always indispensable, the addition of a sham-controlled group to such a trial can contribute to the quality of the research. However, the design of a sham (hyperbaric) treatment is associated with several considerations regarding adequate blinding and the use of pressure and oxygen. This narrative review discusses information on the sham profile and the blinding and safety of double-blind trials in hyperbaric medicine, irrespective of the indication for treatment. Methods MEDLINE, Embase and CENTRAL were searched for sham-controlled trials on hyperbaric oxygen therapy. The control treatment was considered sham if patients were blinded to their allocation and treatment took place in a hyperbaric chamber, with no restrictions regarding pressurization, oxygen levels or indication. Studies involving children or only one session of hyperbaric oxygen were excluded. Information on (the choice of) treatment profile, blinding measures, patient's perception regarding allocation and safety issues was extracted from eligible studies. Results A total of 42 eligible trials were included. The main strategies for sham treatment were (1) use of a lower pressure than that of the hyperbaric oxygen group, while breathing 21% oxygen; (2) use of the same pressure as the hyperbaric oxygen group, while breathing an adjusted percentage of oxygen; and (3) use of the same pressure as the hyperbaric oxygen group, while breathing 21% oxygen. The advantages and disadvantages of each strategy are discussed using the information provided by the trials. Conclusion Based on this review, using a lower pressure

Development of underwater and hyperbaric medicine in Malaysia.

PubMed

Rozali, A; Rampal, K G; Zin, B Mohd; Sherina, M S; Khairuddin, H; Abd Halim, M; Sulaiman, A

2006-12-01

Underwater and Hyperbaric Medicine is a treatment modality gaining recognition in Malaysia. It uses the hyperbaric oxygen therapy (HBOT) approach where patients are placed in recompression chambers and subjected to oxygen therapy under pressure. In Malaysia it was introduced as early as the 1960's by the Royal Malaysian Navy to treat their divers for decompression illness (DCI), arterial gas embolism (AGE) and barotraumas. Other sectors in the armed forces, universities and private health centres began developing this approach too in the late 1990's, for similar purposes. In 1996, Underwater and Hyperbaric Medicine began gaining its popularity when the Institute of Underwater and Hyperbaric Medicine at the Armed Forces Hospital in Lumut started treating specific clinical diseases such as diabetic foot ulcers, osteomyelitis, and carbon monoxide poisoning and other diseases using HBOT. This paper discusses the development of this interesting treatment modality, giving a brief historical overview to its current development, as well as provides some thought for its future development in Malaysia.

Effect of Electroacupuncture on Transcutaneous Oxygen Partial Pressure During Hyperbaric Oxygen Therapy in Healthy Individuals.

PubMed

Qu, Lan; Ye, Yong; Li, Chunfeng; Gao, Guangkai

2015-01-01

The goal of hyperbaric oxygen therapy (HBOT) is to increase the oxygen (O₂) supply to the body significantly. Because of the toxic side effects and complications of hyperbaric oxygen (HBO₂), the environmental pressure and treatment time must be restricted. The research team hypothesized that other therapies administered during HBOT could safely improve the value of the arterial oxygen partial pressure (PaO₂) during HBOT and improve its therapeutic effect. The study intended to investigate whether electroacupuncture (EA) while receiving HBOT had a greater effect for healthy individuals than HBOT or EA alone or EA combined with normobaric pure oxygen (pure O₂). The research team designed a randomized, controlled trial. The study was performed in the Department of Hyperbaric Medicine at the No. 401 Hospital of the People's Liberation Army in Qingdao, China. A total of 81 volunteers were recruited. After thorough physical examination and laboratory testing, 21 volunteers were excluded from the study. Participants included 60 healthy volunteers. Participants were randomly assigned to 1 of 4 groups of 15 participants each: (1) an HBOT group, (2) an EA group, (3) an EA During HBOT group, and (4) an EA Combined With Pure O₂group. Because at the current technology level a blood gas analyzer cannot test PaO₂during HBOT, transcutaneous oxygen partial pressure (PtcO₂) of the participants was tested instead. Before, during, and after EA, variations in PtcO₂were monitored in each group. For the EA During HBOT group, (1) the increase in PtcO₂during EA was significantly greater than that observed for the other 3 groups (P > .05). The EA During HBOT method provided improvements in the efficacy, safety, and tolerability of HBOT, and the study's results partially demonstrated the accuracy of the research team's hypothesis that EA therapy applied during HBOT could safely improve the value of PtcO₂(PaO₂) during HBOT and produce a greater therapeutic effect.

Hyperbaric oxygen: B-level evidence in mild traumatic brain injury clinical trials.

PubMed

Figueroa, Xavier A; Wright, James K

2016-09-27

First, to demonstrate that B-level evidence exists for the use of hyperbaric oxygen therapy (HBOT) as an effective treatment in mild to moderate traumatic brain injury/persistent postconcussion syndrome (mTBI/PPCS). Second, to alert readers and researchers that currently used pressurized air controls (≥21% O2, >1.0 ATA) are therapeutically active and cannot be utilized as sham controls without further validation. Review of published, peer-reviewed articles of HBOT prospective and controlled clinical trials of mTBI/PPCS symptoms. Published results demonstrate that HBOT is effective in the treatment of mTBI/PPCS symptoms. Doses of oxygen that are applied at ≥21% O2 and at pressures of >1.0 ATA produce improvements from baseline measures. Some of the recently published clinical trials are mischaracterized as sham-controlled clinical trials (i.e., sham = 21% O2/1.2-1.3 ATA), but are best characterized as dose-varying (variation in oxygen concentration, pressure applied, or both) clinical trials. Hyperbaric oxygen and hyperbaric air have demonstrated therapeutic effects on mTBI/PPCS symptoms and can alleviate posttraumatic stress disorder symptoms secondary to a brain injury in 5 out of 5 peer-reviewed clinical trials. The current use of pressurized air (1.2-1.3 ATA) as a placebo or sham in clinical trials biases the results due to biological activity that favors healing. © 2016 American Academy of Neurology.

Randomized Trial of Hyperbaric Oxygen Therapy for Children with Autism

ERIC Educational Resources Information Center

Granpeesheh, Doreen; Tarbox, Jonathan; Dixon, Dennis R.; Wilke, Arthur E.; Allen, Michael S.; Bradstreet, James Jeffrey

2010-01-01

Autism Spectrum Disorders (ASDs) are characterized by the presence of impaired development in social interaction and communication and the presence of a restricted repertoire of activity and interests. While numerous treatments for ASDs have been proposed, very few have been subjected to rigorous scientific investigation. Hyperbaric oxygen therapy…

Oxygen toxicity in the perfused rat liver and lung under hyperbaric conditions.

PubMed Central

Nishiki, K; Jamieson, D; Oshino, N; Chance, B

1976-01-01

1. In the lung and liver of tocopherol-deficient rats, the activities of glutathione peroxidase and glucose 6-phosphate dehydrogenase were increased substantially, suggesting an important role for both enzymes in protecting the organ against the deleterious effects of lipid peroxides. 2. Facilitation of the glutathione peroxidase reaction by infusing t-butyl hydroperoxide caused the oxidation of nicotinamide nucleotides and glutathione, resulting in a concomitant increase in the rate of release of oxidized glutathione into the perfusate. Thus the rate of production of lipid peroxide and H2O2 in the perfused organ could be compared by simultaneous measurement of the rate of glutathione release and the turnover number of the catalase reaction. 3. On hyperbaric oxygenation at 4 X 10(5)Pa, H2O2 production, estimated from the turnover of the catalase reaction, was increased slightly in the liver, and glutathione release was increased slightly, in both lung and liver. 4. Tocopherol deficiency caused a marked increase in lipid-peroxide formation as indicated by a corresponding increase in glutathione release under hyperbaric oxygenation, with a further enhancement when the tocopherol-deficient rats were also starved. 5. The study demonstrates that the primary response to hyperbaric oxygenation is an elevation of the rate of lipid peroxidation rather than of the rate of formation of H2O2 or superoxide. PMID:12754

Hyperbaric oxygen therapy in combination with systemic treatment of sickle cell disease presenting as central retinal artery occlusion: a case report.

PubMed

Canan, Handan; Ulas, Burak; Altan-Yaycioglu, Rana

2014-11-17

We describe hyperbaric oxygen therapy for the treatment of central retinal artery occlusion in a young adult with sickle cell disease. A 25-year-old Turkish man with a history of sickle cell disease developed sudden painless loss of vision in the left eye and was hospitalized for diagnosis and treatment. Central retinal artery occlusion was diagnosed with retinal whitening, cherry red spot, and delayed arteriovenous transit on fluorescein angiography. He underwent exchange transfusion and hyperbaric oxygen therapy. In the following three months, his visual acuity improved to 20/30. In this present case with sickle cell disease, the visual acuity improved with hyperbaric oxygen therapy in addition to systemic therapy. The result of our case suggests that hyperbaric oxygen therapy may be beneficial in the treatment of central retinal artery occlusion.

Hyperbaric oxygen therapy as treatment for bilateral arm compartment syndrome after CrossFit: case report and literature review.

PubMed

Mendes, Adriano Fernando; Neto, José da Mota; Heringer, Erica Maciel; de Simoni, Leandro Furtado; Pires, Diego Demolinari; Labronici, Pedro José

2018-01-01

CrossFit is a physical fitness program characterized by high-intensity workouts that can be associated with serious injury. Acute compartment syndrome in the upper limbs is a rare occurrence. It may occur after intense physical exercise, and its usual treatment is surgical. Hyperbaric oxygen therapy is a treatment described as adjunctive in cases of compartmental syndrome. We describe the case of a CrossFit practitioner who, after intense training, developed progressive symptoms of rhabdomyolysis and acute bilateral arm compartment syndrome, who was successfully treated with hyperbaric oxygen therapy and required no fasciotomy as surgical treatment. Acute compartment syndrome in the arms after intense physical exercise is a rare occurrence that should be suspected by practitioners of physical activity experiencing intense, disproportionate and progressive pain. In the case presented, hyperbaric oxygen therapy was successfully used in the treatment of the disorder, with satisfactory progress, and without the need for a surgical fasciotomy as therapy. Copyright© Undersea and Hyperbaric Medical Society.

Neuroprotection of hyperbaric oxygen therapy in sub-acute traumatic brain injury: not by immediately improving cerebral oxygen saturation and oxygen partial pressure.

PubMed

Zhou, Bao-Chun; Liu, Li-Jun; Liu, Bing

2016-09-01

Although hyperbaric oxygen (HBO) therapy can promote the recovery of neural function in patients who have suffered traumatic brain injury (TBI), the underlying mechanism is unclear. We hypothesized that hyperbaric oxygen treatment plays a neuroprotective role in TBI by increasing regional transcranial oxygen saturation (rSO 2 ) and oxygen partial pressure (PaO 2 ). To test this idea, we compared two groups: a control group with 20 healthy people and a treatment group with 40 TBI patients. The 40 patients were given 100% oxygen of HBO for 90 minutes. Changes in rSO 2 were measured. The controls were also examined for rSO 2 and PaO 2 , but received no treatment. rSO 2 levels in the patients did not differ significantly after treatment, but levels before and after treatment were significantly lower than those in the control group. PaO 2 levels were significantly decreased after the 30-minute HBO treatment. Our findings suggest that there is a disorder of oxygen metabolism in patients with sub-acute TBI. HBO does not immediately affect cerebral oxygen metabolism, and the underlying mechanism still needs to be studied in depth.

Endoscopic Bubble Trouble: Hyperbaric Oxygen Therapy for Cerebral Gas Embolism During Upper Endoscopy.

PubMed

Cooper, Jeffrey S; Thomas, Jason; Singh, Shailender; Brakke, Tarra

2017-07-01

Gas embolism is a rare but potentially devastating complication of endoscopic procedures. We describe 3 cases of gas embolism which were associated with endoscopic procedures (esophagogastroduodenoscopy and endoscopic retrograde cholangiopancreatography). We treated these at our hyperbaric medicine center with 3 different outcomes: complete resolution, death, and disability. We review the literature regarding this unusual complication of endoscopy and discuss the need for prompt identification and referral for hyperbaric oxygen therapy. Additional adjunctive therapies are also discussed.

Computerized planimetry evaluation of hyperbaric oxygen therapy in the treatment of diabetic foot.

PubMed

Kawecki, Marek; Pasek, Jarosław; Cieślar, Grzegorz; Sieroń, Aleksander; Knefel, Grzegorz; Nowak, Mariusz; Glik, Justyna

2018-01-01

Diabetic foot ulcer is one of the major complications of diabetes mellitus in adults. The aim of the study was to conduct a planimetry evaluation of the effectiveness of hyperbaric oxygen therapy (HBOT) in the treatment of patients with vascular disorders caused by diabetic foot. The study included 94 patients, 30 females (32%) and 64 males (68%), aged 33-76 years, with diabetes lasting 1.5-32 years, who underwent HBOT due to diabetic foot. All patients from that group underwent vascular procedures prior to HBOT. In qualifying patients for hyperbaric oxygen therapy, transcutaneous oximetry method was applied (30-60 exposures in hyperbaric oxygen at pressure of 2.5 ATA). Progress in wound healing was evaluated by computerized planimetry system IRIS 4. In 26 patients the wounds were completely closed and in 37 patients the topical state was significantly improved - the wound surface decreased by 34% in average. During the treatment, in 11 patients amputation of fingers and metatarsal necrotic bones was performed, while in 9 patients amputation was prevented. A planimetry evaluation showed that the application of HBOT in the treatment of diabetic foot enhances foot ulcer healing, reduces tissue damage, contributes to the reduction of complications related to soft tissue and bone infections.

Hyperbaric oxygen therapy in combination with systemic treatment of sickle cell disease presenting as central retinal artery occlusion: a case report

PubMed Central

2014-01-01

Introduction We describe hyperbaric oxygen therapy for the treatment of central retinal artery occlusion in a young adult with sickle cell disease. Case presentation A 25-year-old Turkish man with a history of sickle cell disease developed sudden painless loss of vision in the left eye and was hospitalized for diagnosis and treatment. Central retinal artery occlusion was diagnosed with retinal whitening, cherry red spot, and delayed arteriovenous transit on fluorescein angiography. He underwent exchange transfusion and hyperbaric oxygen therapy. In the following three months, his visual acuity improved to 20/30. Conclusions In this present case with sickle cell disease, the visual acuity improved with hyperbaric oxygen therapy in addition to systemic therapy. The result of our case suggests that hyperbaric oxygen therapy may be beneficial in the treatment of central retinal artery occlusion. PMID:25399776

Hyperbaric oxygen therapy and preconditioning for ischemic and hemorrhagic stroke.

PubMed

Hu, Sheng-Li; Feng, Hua; Xi, Guo-Hua

2016-01-01

To date, the therapeutic methods for ischemic and hemorrhagic stroke are still limited. The lack of oxygen supply is critical for brain injury following stroke. Hyperbaric oxygen (HBO), an approach through a process in which patients breathe in 100% pure oxygen at over 101 kPa, has been shown to facilitate oxygen delivery and increase oxygen supply. Hence, HBO possesses the potentials to produce beneficial effects on stroke. Actually, accumulated basic and clinical evidences have demonstrated that HBO therapy and preconditioning could induce neuroprotective functions via different mechanisms. Nevertheless, the lack of clinical translational study limits the application of HBO. More translational studies and clinical trials are needed in the future to develop effective HBO protocols.

Treatment of portal venous gas embolism with hyperbaric oxygen after accidental ingestion of hydrogen peroxide: a case report and review of the literature.

PubMed

Papafragkou, Sotirios; Gasparyan, Anna; Batista, Richard; Scott, Paul

2012-07-01

It is well known that hydrogen peroxide ingestion can cause gas embolism. To report a case illustrating that the definitive, most effective treatment for gas embolism is hyperbaric oxygen therapy. We present a case of a woman who presented to the Emergency Department with acute abdominal pain after an accidental ingestion of concentrated hydrogen peroxide. Complete recovery from her symptoms occurred quickly with hyperbaric oxygen therapy. This is a case report of the successful use of hyperbaric oxygen therapy to treat portal venous gas embolism caused by hydrogen peroxide ingestion. Hyperbaric oxygen therapy can be considered for the treatment of symptomatic hydrogen peroxide ingestion. Copyright © 2012 Elsevier Inc. All rights reserved.

Human amniotic fluid mesenchymal stem cells in combination with hyperbaric oxygen augment peripheral nerve regeneration.

PubMed

Pan, Hung-Chuan; Chin, Chun-Shih; Yang, Dar-Yu; Ho, Shu-Peng; Chen, Chung-Jung; Hwang, Shiaw-Min; Chang, Ming-Hong; Cheng, Fu-Chou

2009-07-01

Attenuation of pro-inflammatory cytokines and associated inflammatory cell deposits rescues human amniotic fluid mesenchymal stem cells (AFS) from apoptosis. Hyperbaric oxygen (HBO) suppressed stimulus-induced pro-inflammatory cytokine production in blood-derived monocyte-macrophages. Herein, we evaluate the beneficial effect of hyperbaric oxygen on transplanted AFS in a sciatic nerve injury model. Peripheral nerve injury was produced in Sprague-Dawley rats by crushing the left sciatic nerve using a vessel clamp. The AFS were embedded in fibrin glue and delivered to the injured site. Hyperbaric oxygen (100% oxygen, 2 ATA, 60 min/day) was administered 12 h after operation for seven consecutive days. Transplanted cell apoptosis, oxidative stress, inflammatory cell deposits and associated chemokines, pro-inflammatory cytokines, motor function, and nerve regeneration were evaluated 7 and 28 days after injury. Crush injury induced an inflammatory response, disrupted nerve integrity, and impaired nerve function in the sciatic nerve. However, crush injury-provoked inflammatory cytokines, deposits of inflammatory cytokines, and associated macrophage migration chemokines were attenuated in groups receiving hyperbaric oxygen but not in the AFS-only group. No significant increase in oxidative stress was observed after administration of HBO. In transplanted AFS, marked apoptosis was detected and this event was reduced by HBO treatment. Increased nerve myelination and improved motor function were observed in AFS-transplant, HBO-administrated, and AFS/HBO-combined treatment groups. Significantly, the AFS/HBO combined treatment showed the most beneficial effect. AFS in combination with HBO augment peripheral nerve regeneration, which may involve the suppression of apoptotic death in implanted AFS and the attenuation of an inflammatory response detrimental to peripheral nerve regeneration.

Preservation of tumour oxygen after hyperbaric oxygenation monitored by magnetic resonance imaging

PubMed Central

Kinoshita, Y; Kohshi, K; Kunugita, N; Tosaki, T; Yokota, A

1999-01-01

Hyperbaric oxygen (HBO) has been proposed to reduce tumour hypoxia by increasing the dissolved molecular oxygen in tissue. Using a non-invasive magnetic resonance imaging (MRI) technique, we monitored the changes in MRI signal intensity after HBO exposure because dissolved paramagnetic molecular oxygen itself shortens the T1 relation time. SCCVII tumour cells transplanted in mice were used. The molecular oxygen-enhanced MR images were acquired using an inversion recovery-preparation fast low angle shot (IR-FLASH) sequence sensitizing the paramagnetic effects of molecular oxygen using a 4.7 tesla MR system. MR signal of muscles decreased rapidly and returned to the control level within 40 min after decompression, whereas that of tumours decreased gradually and remained at a high level 60 min after HBO exposure. In contrast, the signal from the tumours in the normobaric oxygen group showed no significant change. Our data suggested that MR signal changes of tumours and muscles represent an alternation of extravascular oxygenation. The preserving tumour oxygen concentration after HBO exposure may be important regarding adjuvant therapy for cancer patients. © 2000 Cancer Research Campaign PMID:10638972

Hydrostatic Hyperbaric Chamber Ventilation System

NASA Technical Reports Server (NTRS)

Sargusingh, Miriam M.

2011-01-01

The hydrostatic hyperbaric chamber (HHC) represents the merger of several technologies in development for NASA aerospace applications, harnessed to directly benefit global health. NASA has significant experience developing composite hyperbaric chambers for a variety of applications, including the treatment of medical conditions. NASA also has researched the application of water-filled vessels to increase tolerance of acceleration forces. The combination of these two applications has resulted in the hydrostatic chamber, which has been conceived as a safe, affordable means of making hyperbaric oxygen therapy available in the developing world for the treatment of a variety of medical conditions. Specifically, hyperbaric oxygen therapy is highly-desired as a possibly curative treatment for Buruli Ulcer, an infectious condition that afflicts children in sub-Saharan Africa. Hyperbaric oxygen therapy is simply too expensive and too dangerous to implement in the developing world using standard equipment. The hydrostatic hyperbaric chamber technology changes the paradigm. The HHC differs from standard hyperbaric chambers in that the majority of its volume is filled with water which is pressurized by oxygen being supplied in the portion of the chamber containing the patient s head. This greatly reduces the amount of oxygen required to sustain a hyperbaric atmosphere, thereby making the system more safe and economical to operate. An effort was taken to develop an HHC system to apply HBOT to children that is simple and robust enough to support transport, assembly, maintenance and operation in developing countries. This paper details the concept for an HHC ventilation and pressurization system that will provide controlled pressurization of the system, and provide adequate washout of carbon dioxide while the subject is enclosed in the confined space during the administration of the medical treatment. The concept took into consideration operational complexity, safety to the

Hyperbaric hyperoxia reversibly inhibits erythrocyte phospholipid fatty acid turnover

NASA Technical Reports Server (NTRS)

Dise, Craig A.; Clark, James M.; Lambersten, Christian J.; Goodman, David B. P.

1987-01-01

The effect of hyperbaric hyperoxia on the acylation of membrane phospholipid was studied by measuring the rates of activation of exogenous tritiated oleic acid to acyl thioester and of transesterification of the thioester into membrane phospholipids in intact human erythrocytes obtained 1 h after an exposure of the subjects to a hyperbaric oxygen atmosphere (3.5 h, 100 pct O2, 3 ATA). Exposure to pure oxygen was found to inhibit both the acylation and transesterification reactions by more than 30 percent, with partial recovery detected 24 h later. On the other hand, no rate changes were observed when isolated membranes from the same batches of cells were used in similar experiments. It is suggested that the decrease in the incorporation of tritiated oleic acid after hyperbaric hyperoxia may reflect an early event in the pathogenesis of oxygen-induced cellular injury and that it may be a useful index for the assessment of the tolerance of tissues to hyperoxia.

Hyperbaric oxygen for mild traumatic brain injury: Design and baseline summary.

PubMed

Weaver, Lindell K; Chhoeu, Austin; Lindblad, Anne S; Churchill, Susan; Wilson, Steffanie H

2016-01-01

The Brain Injury and Mechanisms of Action of Hyperbaric Oxygen for Persistent Post-Concussive Symptoms after Mild Traumatic Brain Injury (mTBI) (BIMA) study, sponsored by the Department of Defense, is a randomized double-blind, sham-controlled clinical trial that has a longer duration of follow-up and more comprehensive assessment battery compared to recent HBO₂ studies. BIMA randomized 71 participants from September 2012 to May 2014. Primary results are expected in 2017. Randomized military personnel received hyperbaric oxygen (HBO₂) at 1.5 atmospheres absolute (ATA) or sham chamber sessions at 1.2 ATA, air, for 60 minutes daily for 40 sessions. Outcomes include neuropsychological, neuroimaging, neurological, vestibular, autonomic function, electroencephalography, and visual systems evaluated at baseline, immediately following intervention at 13 weeks and six months with self-report symptom and quality of life questionnaires at 12 months, 24 months and 36 months. Characteristics include: median age 33 years (range 21-53); 99% male; 82% Caucasian; 49% diagnosed post-traumatic stress disorder; 28% with most recent injury three months to one year prior to enrollment; 32% blast injuries; and 73% multiple injuries. This manuscript describes the study design, outcome assessment battery, and baseline characteristics. Independent of a therapeutic role of HBO₂, results of BIMA will aid understanding of mTBI. ClinicalTrials.gov Identifier: NCT01611194; https://clinicaltrials.gov/show/NCT01611194. Copyright© Undersea and Hyperbaric Medical Society.

Hyperbaric oxygenation affects the mechanisms of acetylcholine-induced relaxation in diabetic rats.

PubMed

Unfirer, Sanela; Mihalj, Martina; Novak, Sanja; Kibel, Aleksandar; Cavka, Ava; Mijalevic, Zrinka; Gros, Mario; Brizic, Ivica; Budimir, Danijela; Cosic, Anita; Boban, Mladen; Drenjancevic, Ines

2016-01-01

The effects of hyperbaric oxygenation (HBO₂) on acetylcholine-induced vasorelaxation (AChIR) were evaluated in male Sprague-Dawley (SD) rats randomized into four groups: healthy controls (Ctrl), diabetic rats (DM), and control and diabetic rats that underwent hyperbaric oxygenation (Ctrl+HBO₂ and DM+HBO₂). AChIR was measured in aortic rings, with L-NAME, indomethacin, or MS-PPOH and a combination of inhibitors. mRNA expression of eNOS, iNOS, COX-1 and COX-2 was assessed by qPCR, and protein expression of CYP4A(1-3) by Western blot. Plasma antioxidative capacity and systemic oxidative stress were determined with the ferric reducing ability of plasma (FRAP) and thiobarbituric acid-reactive substances (TBARS) assays, respectively. AChIR was preserved in all groups of rats, but mediated with different mechanisms. In all experimental groups of rats, AChIR was mediated mainly by NO, with the contribution of CYP450 vasodilator metabolites. This effect was the most prominent in the DM+HBO₂ group of rats. The TBARS was significantly higher in both DM and DM+HBO₂ groups compared to respective controls. eNOS expression was upregulated in the DM+HBO₂ group compared to other groups, COX-1 expression was upregulated in the DM+HBO₂ group compared to the control. CYP450-4A1 / A2/A3protein expression was significantly higher expressed in both hyperbaric groups compared to their respective controls. In conclusion, HBO₂ affected all three vasodilator pathways and shifted AChIR to CYP450 enzymes pathway. Copyright© Undersea and Hyperbaric Medical Society.

The negative effect of hyperbaric oxygen therapy at the acute phase of electrochemical esophageal burn induced by button battery ingestion.

PubMed

Aydin, Atakan; Aktas, Samil; Hafiz, Gunter; Kabakas, Fatih; Erer, Metin; Bilgic, Bilge

2004-07-01

Ingestion of button battery, if lodges in esophagus, causes mucosal destruction in esophagus and may damage surrounding tissues due to electrochemical reactions which may lead to esophagus perforation, tracheosefageal fistula and other serious problems. We designed an experimental study to test the effect of hyperbaric oxygen therapy on battery induced electrochemical tissue damage in the esophagus of a rabbit model and possible change with duration of contact time. Button batteries were inserted in esophagus of 40 rabbits which were divided into four groups. Groups 1 and 2 had 15 min of duration of contact time of battery in esophagus, while Groups 3 and 4 had 30 min. Groups 1 and 3 had hyperbaric oxygen therapy for 3 days; Groups 2 and 4 did not. At the end of 3rd day all animals were sacrified and samples were taken from the esophagus for determination of malondialdehyde levels and for histopathological examination to compare: mucosal destruction, muscular layer involvement, perforation and tracheal involvement between groups. Malondialdehyde levels, mucosal destruction, muscular layer involvement, perforation and tracheal involvement were significantly higher in groups which had 30 min of contact time compared to groups which had 15 min. The same assessments were significantly higher in Group 1 (15 min of contact time with hyperbaric oxygen therapy) compared to Group 2 (15 min of contact time without hyperbaric oxygen therapy). However, the difference between Group 3 (30 min of contact time with hyperbaric oxygen therapy) and Group 4 (30 min of contact time, no hyperbaric oxygen therapy) was not significant. Our study demonstrated that if contact time is 15 min HBO had an additive adverse effect to electrochemically burned esophagus by increasing free radicals and eventually tissue damage. However, if the contact time is 30 min its adverse effect is shielded by huge electrochemical destruction due to long contact time.

[Clinical analysis of using hyperbaric oxygen comprehensive therapy for the treatment of 110 cases noise induced deafness].

PubMed

Tan, Junwu; Li, Liangbo; Peng, Hong

2014-10-01

To observe the clinical effects of using hyperbaric oxygen comprehensive therapy for the treatment of noise induced deafness. From May 2009 to April 2012 in our hospital 220 cases of noise induced deafness patients were chosen and they were all construction workers; According to different treatments all patients were divided into the control group (110 cases) only having hyperbaric oxygen treatment and the treatment group (110 cases) using hyperbaric oxygen comprehensive therapy, including control group simply by. Hearing improvements of the two groups were recorded and compared. The cure rate of the comprehensive therapy group was 53.6%which was higher than that of the control group 38.2% (χ(2) = 5.290, P < 5.290), while the total effective rate of the comprehensive therapy group was 79.1%which was also significantly higher than that of the control group 67.3% (χ(2) = 3.914, P < 0.05). After two courses of comprehensive treatment the cure rate and total effective rate were 47.3%and 73.6%respectively, while after four courses of comprehensive treatment group the cure rate and total effective rate turned to be 60.9% and 84.5% respectively, which had significant difference (χ(2) values were 4.118 and 3.958, P < 0.05). The cure rate and total effective rate of the comprehensive therapy group are higher than the simple hyperbaric oxygen treatment group, which is worthy of clinical application and promotion in the future.

Hyperbaric Oxygen Therapy in the Treatment of Chronic Mild-Moderate Blast-Induced Traumatic Brain Injury Post-Concussion Syndrome (PCS) and Post Traumatic Stress Disorder (PTSD)

DTIC Science & Technology

2016-10-01

Award Number: W81XWH-10-1-0962 TITLE: Hyperbaric Oxygen Therapy in the Treatment of Chronic Mild-Moderate Blast-Induced Traumatic Brain Injury...164. TITLE AND SUBTITLE 5a. CONTRACT NUMBER W81XWH-10-1-0962 Hyperbaric Oxygen Therapy in the Treatment of Chronic Mild-Moderate Blast-Induced...month follow-up period post-hyperbaric oxygen treatment. 1 additional subject is scheduled to be screened in October 2016 and 3 are awaiting first

Retrospective study of factors affecting non-healing of wounds during hyperbaric oxygen therapy.

PubMed

Oubre, C M; Roy, A; Toner, C; Kalns, J

2007-06-01

To identify potential factors, including cigarette smoking and diabetes status, that affect wound-healing outcomes during a six-week course of hyperbaric oxygen therapy (HBOT). Seventy-three patients with 85 non-healing lower extremity wounds were treated with hyperbaric oxygen therapy (100% oxygen, 2.4 atmosphere absolute, (ATA), for 90 minutes). The wound area was evaluated over the six-week treatment period. A non-hierarchical clustering analysis of normalised wound-area data revealed that healing responses could be segregated into three groups: robust healing (n=31, over 50% reduction in area), minimal healing (n=33, 15% reduction) and non-healing (n=21,60% increase in area). Further analysis revealed that cigarette smoking was associated with poor response (p<0.0001), whereas diabetes was not. Robust responders had higher blood levels of creatinine and urea nitrogen, increased peripheral oxygenation (TcpO2), and were younger than less responsive patients. The results suggest that response to HBOT is variable and some patients do not benefit from it. Clinicians should evaluate available laboratory values, age and social history to determine if a patient is likely to benefit from HBOT.

Cerebral arterial gas embolism from attempted mechanical thrombectomy: recovery following hyperbaric oxygen therapy.

PubMed

Segan, Louise; Permezel, Fiona; Ch'ng, Wei; Millar, Ian; Brooks, Mark; Lee-Archer, Matt; Cloud, Geoffrey

2018-04-01

Cerebral arterial gas embolism is a recognised complication of endovascular intervention with an estimated incidence of 0.08%. Its diagnosis is predominantly clinical, supported by neuroimaging. The treatment relies on alleviating mechanical obstruction and reversing the proinflammatory processes that contribute to tissue ischaemia. Hyperbaric oxygen therapy is an effective treatment and has multiple mechanisms to reverse the pathological processes involved in cerebral arterial gas embolism. Symptomatic cerebral arterial gas embolism is a rare complication of endovascular intervention for acute ischaemic stroke. Although there are no previous descriptions of its successful treatment with hyperbaric oxygen therapy following mechanical thrombectomy, this is likely to become more common as mechanical thrombectomy is increasingly used worldwide to treat acute ischaemic stroke. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Hyperbaric nitrogen prolongs breath-holding time in humans.

PubMed

Morooka, H; Wakasugi, Y; Shimamoto, H; Shibata, O; Sumikawa, K

2000-09-01

Either an increase in PaCO(2) or a decrease in PaO(2), can affect respiratory stimulation through respiratory centers, thus influencing breath-holding time (BHT). This study was designed to determine whether and how hyperbaric air could influence BHT in comparison with hyperbaric oxygen in humans. We studied 36 healthy volunteers in a multiplace hyperbaric chamber. BHT, pulse oximeter, and transcutaneous carbon dioxide tension were measured at 1 and 2.8 atmosphere absolute (ATA) in two groups. Group A (n = 20) breathed air. Group O (n = 16) breathed oxygen with a face mask (5 L/min). BHTs were 108 +/- 28 s at 1.0 ATA and 230 +/- 71 s at 2.8 ATA in Group A, and 137 +/- 48 s at 1.0 ATA and 180 +/- 52 s at 2.8 ATA in Group O. Transcutaneous carbon dioxide tension in Group A (59 +/- 2 mm Hg) was higher than that in Group O (54 +/- 2 mm Hg) at the end of maximal breath-holding at 2.8 ATA. The prolongation of BHT in hyperbaric air is significantly greater than that in hyperbaric oxygen. Breath-holding time is significantly prolonged in hyperbaric air than it is in hyperbaric oxygen. The mechanism involves the anesthetic effect of nitrogen suppressing the suffocating feeling during breath-holding.

Normal carboxyhaemoglobin level in carbon monoxide poisoning treated with hyperbaric oxygen therapy.

PubMed

Helgeson, Scott A; Wilson, Michael E; Guru, Pramod K

2017-07-24

Throughout the world both intentional and inadvertent exposure to carbon monoxide (CO) remains an important public health issue. While CO poisoning can be lethal, the morbidity is predominantly due to nervous system injury. A previously healthy 22-year-old woman was found unconscious at home by her sister. Her parents were found dead in the house with a recent history of a dysfunctional furnace. She was presumed to have CO poisoning despite an initial carboxyhaemoglobin level of 2.5%. Patient had both clinical and radiological evidence of neurological damage. However, with multiple sessions of hyperbaric oxygen (HBO) therapy she recovered to a near normal functional status. There is no consensus that exists among treating physicians about the role of hyperbaric oxygen in management of neurological injury. The case described here has significant neurological damage related to CO exposure but improved after HBO therapy. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Electrotherapy and hyperbaric oxygen: Promising treatments for postradiation complications

DOE Office of Scientific and Technical Information (OSTI.GOV)

King, G.E.; Scheetz, J.; Jacob, R.F.

1989-09-01

Electrotherapy and hyperbaric oxygen therapy have been added to physical therapy to treat patients with postsurgery and radiation sequelae. Problems of reduced oral opening and range of head movement, soft tissue necrosis, osteoradionecrosis, and delayed wound healing were addressed in 37 patients over a 3-year period. Of this group, 16 irradiated maxillary resection patients were specifically followed up to determine the effectiveness of the new modalities on improving reduced oral opening. Although healing and the quality of the soft tissues showed marked improvement there was no significant improvement in oral opening.

[Changes in the oxidant-antioxidant system activity in patients with hepatic failure treated with hyperbaric oxygenation and actoprotectors].

PubMed

Lakhin, R E; Belozerova, L A; Maksimets, V A; Romanov, D M

1999-01-01

Effects of hyperbaric oxygenation, bemitil, and solcoseryl used in preoperative treatment of patients with hepatic failure on the oxidant-antioxidant system are studied. Lipid peroxidation (LPO) was assessed from changes in the levels of malonic dialdehyde and diene conjugate and the antioxidant system from the number of SH-groups. Hyperbaric oxygenation led to activation of LPO processes. Bemitil decreased the intensity of LPO by extending the potentialities of the antioxidant system. Antioxidant properties of solcoseryl were not realized through the thiol buffer of the antioxidant system. Only a course of treatment with this drug brings about a stable effect.

Effects of heparin and hyperbaric oxygenation on necrosis reduction in an animal model for degloving injuries.

PubMed

Menon, Douglas Neumar; Teixeira, Letícia; Paurosi, Natalha Bristot; Barros, Marcio Eduardo

2017-01-01

to evaluate the efficacy of the treatment with hyperbaric oxygen therapy or with topical and intralesional heparin in an animal model of degloving lesions. we conducted an experimental study with adult, male Wistar rats submitted to degloving of the left hind limb and divided into four groups according to the treatment: Group 1 (control) - without treatment; Group 2 (Heparin) - intralesional application at the time of surgery and topically, in the postoperative period, with heparin spray 10,000IU/mL; Group 3 (hyperbaric oxygenation) - daily sessions of 30 minutes in a hyperbaric chamber with 100% oxygen and 2 ATA pressure; Group 4 (positive control) - administration of a single dose of 45 mg/kg of intraperitoneal allopurinol. On the seventh day, we killed the animals, removed the cutaneous flaps and measured the total and necrotic areas, as well as computed the percentage of necrotic area. the mean percentage of necrosis in the control group was 56.03%; in the positive control group it was 51.36% (p<0.45); in the heparin group, 42.10% (p<0.07); and in the hyperbaric oxygen therapy group, 31.58% (p<0.01) . both hyperbaric oxygen and heparin therapies were effective in reducing the percentage of necrosis in the model studied, although only the hyperbaric oxygenation showed statistical significance. avaliar a eficácia do tratamento com oxigenoterapia hiperbárica ou com heparina tópica e intralesional em modelo animal de desluvamentos. estudo experimental, com ratos adultos machos Wistar, submetidos a desluvamento do membro posterior esquerdo e divididos em quatro grupos, de acordo com o tratamento: Grupo 1 (controle) - sem tratamento; Grupo 2 (Heparina) - aplicação intralesional no momento da cirurgia e tópica, no pós operatório, com spray de heparina 10.000UI/mL; Grupo 3 (oxigenação hiperbárica) - sessões diárias de 30 minutos em câmara hiperbárica com 100% de oxigênio e 2 ATA de pressão; Grupo 4 (controle positivo) - administração de dose única

Management of orbital emphysema secondary to rhegmatogenous retinal detachment repair with hyperbaric oxygen therapy.

PubMed

Iniesta-Sanchez, Dante L; Romero-Caballero, Fatima; Aguirre-Alvarado, Adriana; Rebollo-Hurtado, Victoria; Velez-Montoya, Raul

2016-04-01

To describe the case of orbital subcutaneous emphysema who was successfully treated with hyperbaric oxygen therapy. Case report. Retrospective analysis of medical records and computer tomography images. A 40 years-old female, with retinal detachment who was seen at the emergency department, two weeks after undergoing a combined procedure of pars plana vitrectomy, scleral buckle and Sulfur hexafluoride tamponade. The patient complained of pain, decrease eye movement and edema of the upper eyelid. Clinical examination revealed periorbital crepitus. She was treated immediately with soft tissue decompression with small-gauge needle. Orbital emphysema recurred quickly, indicating possible gas trapped in the soft tissue. Using the US NAVY decompression protocol we were able to achieve fast clinical improvement. The protocol was repeated in several occasions until complete resolution. Hyperbaric oxygen therapy is an effective treatment for orbital and periorbital emphysema, due to its property of helping accelerate N 2 elimination from adipose tissue.

Hyperbaric oxygen therapy in BKV-associated hemorrhagic cystitis refractory to intravenous and intravesical cidofovir: case report and review of literature.

PubMed

Focosi, Daniele; Maggi, Fabrizio; Pistolesi, Donatella; Benedetti, Edoardo; Papineschi, Federico; Galimberti, Sara; Ceccherini-Nelli, Luca; Petrini, Mario

2009-04-01

Hemorrhagic cystitis is a common complication in hematopoietic stem cell transplant recipients. We report here a case of severe BKV-associated hemorrhagic cystitis who did not respond to intravenous cidofovir. Overt hematuria successfully resolved after a few days on hyperbaric oxygen and intravesical instillations of cidofovir, while BK viruria dropped after a few weeks and remained low. We review the literature for therapeutic options in hemorrhagic cystitis and try to explain how hyperbaric oxygen stimulates mucosal repair in the urinary bladder.

An anti-barotrauma system for preventing barotrauma during hyperbaric oxygen therapy.

PubMed

Song, Moon; Hoon, Se Jeon; Shin, Tae Min

2018-01-01

In the present study, a tympanometry-based anti-barotrauma (ABT) device was designed using eardrum admittance measurements to develop an objective method of preventing barotrauma that occurs during hyperbaric oxygen (HBO₂) therapy. The middle ear space requires active equalization, and barotrauma of these tissues during HBO₂therapy constitutes the most common treatment-associated injury. Decongestant nasal sprays and nasal steroids are used, but their efficacy is questionable to prevent middle ear barotrauma (MEB) during HBO₂ treatment. Accordingly, a tympanometry-based ABT device was designed using eardrum admittance measurements to develop an objective method for preventing MEB, which causes pain and injury, and represents one of the principal reasons for patients to stop treatment. This study was conducted to test a novel technology that can be used to measure transmembrane pressures, and provide chamber attendants with real-time feedback regarding the patient's equalization status prior to the onset of pain or injury. Eardrum admittance values were measured according to pressure changes inside a hyperbaric oxygen chamber while the system was fitted to the subject. When the pressure increased to above 200 daPa, eardrum admittance decreased to 16.255% of prepressurization levels. After pressure equalization was achieved, eardrum admittance recovered to 95.595% of prepressurization levels. A one-way repeated measures analysis of variance contrast test was performed on eardrum admittance before pressurization versus during pressurization, and before pressurization versus after pressure equalization. The analysis revealed significant differences at all points during pressurization (P⟨0.001), but no significant difference after pressure equalization was achieved. This ABT device can provide objective feedback reflecting eardrum condition to the patient and the chamber operator during HBO₂ therapy. Copyright© Undersea and Hyperbaric Medical Society.

The treatment of tumors by the induction of anemia and irradiation in hyperbaric oxygen

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sealy, R.; Jacobs, P.; Wood, L.

1989-08-01

Because increased effects have been achieved when murine tumors are irradiated after a period of hypoxia and because of anecdotal clinical experiences of an improved result after irradiation of previously anemic patients in hyperbaric oxygen, the relationship between irradiation and increased survival was investigated in seventy-two patients with advanced head and neck or cervical cancer. Anemia was achieved by means of a two-stage isovolemic venesection maintained for seventy-two hours, hemoglobin was returned to a normal level, and treatment in hyperbaric oxygen was started. Marked tumor shrinkage after the induction of anemia and before radiotherapy was seen and was probably disease,more » site, and hemoglobin level related. As a result, a possible new approach to cancer therapy is suggested. After completion of therapy, the 1-year disease-free survival for patients with head and neck and cervical cancer was not improved, but the 21-month survival for cervical cancer was improved. Further studies are strongly urged.« less

Hyperbaric Side Effects in a Traumatic Brain Injury Randomized Clinical Trial

DTIC Science & Technology

2012-01-01

aHrQ) evidence report/technology assessment, Number 85, “Hyperbaric oxygen therapy for brain injury, cerebral palsy , and stroke” [1]. the report...Carson S, Ash JS, Russman BS, Stavri PZ, Krages KP, et al. Hyperbaric oxygen therapy for brain injury, cerebral palsy , and stroke. Rockville, MD...clini- cal trial to compare the the effect of hyperbaric to normobaric hyperoxia on cerebral metabolism, intracranial pressure, and oxygen toxicity in

Hyperbaric oxygen therapy for traumatic brain injury: bench-to-bedside

PubMed Central

Hu, Qin; Manaenko, Anatol; Xu, Ting; Guo, Zhenni; Tang, Jiping; Zhang, John H.

2016-01-01

Traumatic brain injury (TBI) is a serious public health problem in the United States. Survivors of TBI are often left with significant cognitive, behavioral, and communicative disabilities. So far there is no effective treatment/intervention in the daily clinical practice for TBI patients. The protective effects of hyperbaric oxygen therapy (HBOT) have been proved in stroke; however, its efficiency in TBI remains controversial. In this review, we will summarize the results of HBOT in experimental and clinical TBI, elaborate the mechanisms, and bring out our current understanding and opinions for future studies. PMID:27867476

Effects of hyperbaric, normobaric and hypobaric oxygen supplementation on retinal vessels in newborn rats: a preliminary study.

PubMed

Ricci, B

1987-03-01

An experimental study was conducted on eight litters of newborn rats to evaluate the effects of supplemental oxygen administration on the retinal vasculature. The animals and their mothers were kept inside a pressure chamber and treated for the first 5 days of life. On the sixth day, they were removed and kept for five more days under room air and normobaric conditions. Three litters received continuous flow oxygen at 80% at a compression pressure of +81 kPa, one litter oxygen at 80% at a pressure of -39.5 kPa atms and three other litters received oxygen at 80% under normobaric conditions. The eighth litter was treated with room air oxygen at a compression pressure of +81 kPa. A severe retinopathy with marked retinal neovascularization was seen only in the newborn animals of the litters that received oxygen supplementation under normobaric or hypobaric conditions. Retinal vessels showed no pathological changes in the litters treated with hyperbaric normoxia or hyperoxia. It is possible to hypothesize that the prolonged period of oxygen supplementation failed to produce harmful effects on the retinal vasculature because the moderate hyperbarism caused mild retinal and choroidal vasoconstriction thus preventing excessive oxygen transport to the inner retina from the choroid during hyperoxia without inducing structural damage to the retinal tissue.

Hyperbaric Oxygen Therapy and Oxygen Compatibility of Skin and Wound Care Products

PubMed Central

Bernatchez, Stéphanie F.; Tucker, Joseph; Chiffoleau, Gwenael

2017-01-01

Objective: Use test methods to assess the oxygen compatibility of various wound care products. Approach: There are currently no standard test methods specifically for evaluating the oxygen compatibility and safety of materials under hyperbaric oxygen (HBO) conditions. However, tests such as the oxygen index (OI), oxygen exposure (OE), and autogenous ignition temperature (AIT) can provide useful information. Results: The OI test measures the minimum oxygen concentration that will support candle-like burning, and it was used to test 44 materials. All but two exhibited an OI equal to or greater (safer) than a control material commonly used in HBO. The OE test exposes each material to an oxygen-enriched atmosphere (>99.5% oxygen) to monitor temperature and pressure for an extended duration. The results of the OE testing indicated that none of the 44 articles tested with this method self-ignited within the 60°C, 3 atm pressurized oxygen atmosphere. The AIT test exposes materials to a rapid ramp up in temperature in HBO conditions at 3 atm until ignition occurs. Ten wound care materials and seven materials usually avoided in HBO chambers were tested. The AIT ranged from 138°C to 384°C for wound care products and from 146°C to 420°C for the other materials. Innovation: This work provides useful data and recommendations to help develop a new standard approach for evaluating the HBO compatibility of wound care products to ensure safety for patients and clinicians. Conclusion: The development of an additional test to measure the risk of electrostatic discharge of materials in HBO conditions is needed. PMID:29098113

Hyperbaric Oxygen Therapy for Radiation-Induced Cystitis and Proctitis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oliai, Caspian; Fisher, Brandon; Jani, Ashish

Purpose: To provide a retrospective analysis of the efficacy of hyperbaric oxygen therapy (HBOT) for treating hemorrhagic cystitis (HC) and proctitis secondary to pelvic- and prostate-only radiotherapy. Methods and Materials: Nineteen patients were treated with HBOT for radiation-induced HC and proctitis. The median age at treatment was 66 years (range, 15-84 years). The range of external-beam radiation delivered was 50.0-75.6 Gy. Bleeding must have been refractory to other therapies. Patients received 100% oxygen at 2.0 atmospheres absolute pressure for 90-120 min per treatment in a monoplace chamber. Symptoms were retrospectively scored according to the Late Effects of Normal Tissues-Subjective, Objective,more » Management, Analytic (LENT-SOMA) scale to evaluate short-term efficacy. Recurrence of hematuria/hematochezia was used to assess long-term efficacy. Results: Four of the 19 patients were lost to follow-up. Fifteen patients were evaluated and received a mean of 29.8 dives: 11 developed HC and 4 proctitis. All patients experienced a reduction in their LENT-SOMA score. After completion of HBOT, the mean LENT-SOMA score was reduced from 0.78 to 0.20 in patients with HC and from 0.66 to 0.26 in patients with proctitis. Median follow-up was 39 months (range, 7-70 months). No cases of hematuria were refractory to HBOT. Complete resolution of hematuria was seen in 81% (n = 9) and partial response in 18% (n = 2). Recurrence of hematuria occurred in 36% (n = 4) after a median of 10 months. Complete resolution of hematochezia was seen in 50% (n = 2), partial response in 25% (n = 1), and refractory bleeding in 25% (n = 1). Conclusions: Hyperbaric oxygen therapy is appropriate for radiation-induced HC once less time-consuming therapies have failed to resolve the bleeding. In these conditions, HBOT is efficacious in the short and long term, with minimal side effects.« less

Hyperbaric oxygen for neurologic indications--action plan for multicenter trials in: stroke, traumatic brain injury, radiation encephalopathy & status migrainosus.

PubMed

Helms, A; Evans, A W; Chu, J; Sahgal, A; Ostrowski, R; Sosiak, T; Wolf, G; Gillett, J; Whelan, H

2011-01-01

The 2008 Toronto Hyperbaric Medicine Symposium was convened to discuss research into neurologic indications for hyperbaric oxygen therapy (HBO2T). Four topics were particularly addressed: acute ischemic stroke; acute traumatic brain injury; brain radiation necrosis; and status migrainosus. Four multicenter trials were designed and proposed to evaluate the efficacy of HBO2T for these indications and are presented here in addition to brief reviews of the rationale behind each.

Hyperbaric and hypobaric chamber fires: a 73-year analysis.

PubMed

Sheffield, P J; Desautels, D A

1997-09-01

Fire can be catastrophic in the confined space of a hyperbaric chamber. From 1923 to 1996, 77 human fatalities occurred in 35 hyperbaric chamber fires, three human fatalities in a pressurized Apollo Command Module, and two human fatalities in three hypobaric chamber fires reported in Asia, Europe, and North America. Two fires occurred in diving bells, eight occurred in recompression (or decompression) chambers, and 25 occurred in clinical hyperbaric chambers. No fire fatalities were reported in the clinical hyperbaric chambers of North America. Chamber fires before 1980 were principally caused by electrical ignition. Since 1980, chamber fires have been primarily caused by prohibited sources of ignition that an occupant carried inside the chamber. Each fatal chamber fire has occurred in an enriched oxygen atmosphere (> 28% oxygen) and in the presence of abundant burnable material. Chambers pressurized with air (< 23.5% oxygen) had the only survivors. Information in this report was obtained from the literature and from the Undersea and Hyperbaric Medical Society's Chamber Experience and Mishap Database. This epidemiologic review focuses on information learned from critical analyses of chamber fires and how it can be applied to safe operation of hypobaric and hyperbaric chambers.

Hyperbaric oxygenation for tumour sensitisation to radiotherapy.

PubMed

Bennett, Michael H; Feldmeier, John; Smee, Robert; Milross, Christopher

2012-04-18

Cancer is a common disease and radiotherapy is one well-established treatment for some solid tumours. Hyperbaric oxygenation therapy (HBOT) may improve the ability of radiotherapy to kill hypoxic cancer cells, so the administration of radiotherapy while breathing hyperbaric oxygen may result in a reduction in mortality and recurrence. To assess the benefits and harms of radiotherapy while breathing HBO. In March 2011 we searched The Cochrane Central Register of Controlled Trials (CENTRAL), (The Cochrane Library, Issue 3), MEDLINE, EMBASE, DORCTHIM and reference lists of articles. Randomised and quasi-randomised studies comparing the outcome of malignant tumours following radiation therapy while breathing HBO versus air. Three review authors independently evaluated the quality of the relevant trials and extracted the data from the included trials. Nineteen trials contributed to this review (2286 patients: 1103 allocated to HBOT and 1153 to control). With HBOT, there was a reduction in mortality for head and neck cancers at both one year and five years after therapy (risk ratio (RR) 0.83, P = 0.03, number needed to treat (NNT) = 11; and RR 0.82, P = 0.03, NNT = 5 respectively), as well as improved local tumour control at three months (RR with HBOT 0.58, P = 0.006, NNT = 7). The effect of HBOT varied with different fractionation schemes. Local tumour recurrence was less likely with HBOT at one year (head and neck: RR 0.66, P < 0.0001, NNT = 5), two years (uterine cervix: RR 0.60, P = 0.04, NNT = 5) and five years (head and neck: (RR 0.77, P = 0.01, NNT = 6). Any advantage is achieved at the cost of some adverse effects. There was a significant increase in the rate of both severe radiation tissue injury (RR 2.35, P < 0.0001, (number needed to harm (NNH) = 8) and the chance of seizures during therapy (RR 6.76, P = 0.03, NNH = 22) with HBOT. There is some evidence that HBOT improves local tumour control and mortality for cancers of the head and neck, and local tumour

Effect of hyperbaric oxygen on the growth and development of medicinal maggots.

PubMed

Sherman, Ronald A; Khavari, Borna; Werner, Darryl

2013-01-01

Some wound care therapists use both maggot debridement therapy (MDT) and hyperbaric oxygen (HBO2) therapy to treat non-healing wounds. Some practitioners have reported success using both MDT and HBO2 therapy concurrently; others have not. To begin evaluating the utility of using MDT and HBO2 therapy concurrently, we assessed the effects of hyperbaric oxygen (HBO2) on maggot growth and development, as a surrogate for debridement capacity. Replicate sets of medical-grade blowfly larvae were placed on liver-agar wound models and exposed to HBO2 at 2.0 atmospheres absolute (atm abs) for 90 minutes on 0 (control), 1, 2 or 3 sequential days. The effects of HBO2 exposure were quantified by measuring the maggots' subsequent growth and development. Exposure to HBO2 was most lethal to young larvae (second instars), but not to older larvae (third instars). There was no dose-relationship between the number of HBO2 treatments and rate of larval survival. Our findings suggest that maggot therapy and HBO2 therapy may be administered concurrently, as long as the larvae are not too immature (that is, as long as they are beyond the second instar) by the time they take their first dive. A clinical trial evaluating the clinical benefits of concurrent HBO2 therapy and MDT is warranted.

Hyperbaric oxygen therapy for the treatment of radiation-induced xerostomia: a systematic review.

PubMed

Fox, Nyssa F; Xiao, Christopher; Sood, Amit J; Lovelace, Tiffany L; Nguyen, Shaun A; Sharma, Anand; Day, Terry A

2015-07-01

Radiation-induced xerostomia is one of the most common morbidities of radiation therapy in patients with head and neck cancer. However, in spite of its high rate of occurrence, there are few effective therapies available for its management. The aim of this study was to assess the efficacy of hyperbaric oxygen on the treatment of radiation-induced xerostomia and xerostomia-related quality of life. PubMed, Google Scholar, and the Cochrane Library were searched for retrospective or prospective trials assessing subjective xerostomia, objective xerostomia, or xerostomia-related quality of life. To be included, patients had to have received radiation therapy for head and neck cancer, but not hyperbaric oxygen therapy (HBOT). The systematic review initially identified 293 potential articles. Seven studies, comprising 246 patients, qualified for inclusion. Of the included studies, 6 of 7 were prospective in nature, and 1 was a retrospective study; and 2 of the 7 were controlled studies. HBOT may have utility for treating radiation-induced xerostomia refractory to other therapies. Additionally, HBOT may induce long-term improvement in subjective assessments of xerostomia, whereas other therapies currently available only provide short-term relief. The strength of these conclusions is limited by the lack of randomized controlled clinical trials. Copyright © 2015 Elsevier Inc. All rights reserved.

Hydrostatic Hyperbaric Chamber Ventilation System

NASA Technical Reports Server (NTRS)

Sarguisingh, Miriam J.

2012-01-01

The hydrostatic hyperbaric chamber (HHC) represents the merger of several technologies in development for NASA aerospace applications, harnessed to directly benefit global health. NASA has significant experience developing composite hyperbaric chambers for a variety of applications. NASA also has researched the application of water-filled vessels to increase tolerance of acceleration forces. The combination of these two applications has resulted in the hydrostatic chamber, which has been conceived as a safe, affordable means of making hyperbaric oxygen therapy (HBOT) available in the developing world for the treatment of a variety of medical conditions. Specifically, HBOT is highly-desired as a possibly curative treatment for Buruli Ulcer, an infectious condition that afflicts children in sub-Saharan Africa. HBOT is simply too expensive and too dangerous to implement in the developing world using standard equipment. The HHC technology changes the paradigm. The HHC differs from standard hyperbaric chambers in that the majority of its volume is filled with water which is pressurized by oxygen being supplied in the portion of the chamber containing the patient s head. This greatly reduces the amount of oxygen required to sustain a hyperbaric atmosphere, thereby making the system more safe and economical to operate. An effort was taken to develop an HHC system to apply HBOT to children that is simple and robust enough to support transport, assembly, maintenance and operation in developing countries. This paper details the concept for an HHC ventilation and pressurization system to provide controlled pressurization and adequate washout of carbon dioxide while the subject is enclosed in the confined space during the administration of the medical treatment. The concept took into consideration operational complexity, safety to the patient and operating personnel, and physiological considerations. The simple schematic, comprised of easily acquired commercial hardware

Clinical effectiveness of hyperbaric oxygen therapy for BK-virus-associated hemorrhagic cystitis after allogeneic bone marrow transplantation.

PubMed

Savva-Bordalo, J; Pinho Vaz, C; Sousa, M; Branca, R; Campilho, F; Resende, R; Baldaque, I; Camacho, O; Campos, A

2012-08-01

Late-onset hemorrhagic cystitis (HC) after allogeneic hematopoietic stem cell transplantation (HSCT) has been associated with BK virus (BKV). Antiviral drugs are of limited efficacy and the optimal treatment for HC has not yet been established. Hyperbaric oxygen (HBO) may benefit these patients. We, therefore, retrospectively evaluated the effectiveness of HBO therapy in 16 patients with HC after allogeneic HSCT. All 16 patients had macroscopic hematuria and BKV infection. Patients received 100% oxygen in a hyperbaric chamber at 2.1 atmospheres for 90 min, 5 days per week, with a median 13 treatments (range, 4-84). Fifteen patients (94%) showed complete resolution of hematuria. Median urinary DNA BKV titers declined after HBO (P<0.05). Patients started on HBO earlier after diagnosis of HC responded sooner (P<0.05). HBO was generally well tolerated and proved to be a reliable option for this difficult to manage condition.

Hyperbaric Oxygen Therapy—A Novel Treatment Modality in Oral Submucous Fibrosis: A Review

PubMed Central

Kumar, M. Ashwini; Radhika, Besta; Reddy, Satya Prakash; Yaga, Uday Shankar

2015-01-01

Oral submucous fibrosis (OSMF) is a chronic, debilitating disease characterized by juxta epithelial fibrosis of the oral cavity and regarded as a potentially malignant disorder. Numerous treatment modalities ranging from various drugs to behavioral therapy have been tried with inconsistent results with varying degrees of success reflecting low predictability, requiring further evaluation and standardization. Novel treatment modality such as Hyperbaric oxygen therapy (HBOT) involves inhalation of 100% oxygen at increased atmospheric pressure usually ranging between 2.0 and 2.5 atmospheres for periods between 60 and 120 min. HBOT which can increase oxygen tension and delivery to oxygen-deficient tissue, is a supplementary therapy to improve hypoxic environment of OSMF and also possesses potent anti-inflammatory properties. This article enlightens on possible beneficial effects of HBOT in the management of OSMF at cellular and molecular level. PMID:26155590

Controlled Evaluation of the Effects of Hyperbaric Oxygen Therapy on the Behavior of 16 Children with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Jepson, Bryan; Granpeesheh, Doreen; Tarbox, Jonathan; Olive, Melissa L.; Stott, Carol; Braud, Scott; Yoo, J. Helen; Wakefield, Andrew; Allen, Michael S.

2011-01-01

Hyperbaric oxygen therapy (HBOT) has been used to treat individuals with autism. However, few studies of its effectiveness have been completed. The current study examined the effects of 40 HBOT sessions at 24% oxygen at 1.3 ATA on 11 topographies of directly observed behavior. Five replications of multiple baselines were completed across a total…

Hyperbaric intensive care technology and equipment.

PubMed

Millar, Ian L

2015-03-01

In an emergency, life support can be provided during recompression or hyperbaric oxygen therapy using very basic equipment, provided the equipment is hyperbaric-compatible and the clinicians have appropriate experience. For hyperbaric critical care to be provided safely on a routine basis, however, a great deal of preparation and specific equipment is needed, and relatively few facilities have optimal capabilities at present. The type, size and location of the chamber are very influential factors. Although monoplace chamber critical care is possible, it involves special adaptations and inherent limitations that make it inappropriate for all but specifically experienced teams. A large, purpose-designed chamber co-located with an intensive care unit is ideal. Keeping the critically ill patient on their normal bed significantly improves quality of care where this is possible. The latest hyperbaric ventilators have resolved many of the issues normally associated with hyperbaric ventilation, but at significant cost. Multi-parameter monitoring is relatively simple with advanced portable monitors, or preferably installed units that are of the same type as used elsewhere in the hospital. Whilst end-tidal CO₂ readings are changed by pressure and require interpretation, most other parameters display normally. All normal infusions can be continued, with several examples of syringe drivers and infusion pumps shown to function essentially normally at pressure. Techniques exist for continuous suction drainage and most other aspects of standard critical care. At present, the most complex life support technologies such as haemofiltration, cardiac assist devices and extra-corporeal membrane oxygenation remain incompatible with the hyperbaric environment.

Effects of hyperbaric oxygen on Pseudomonas aeruginosa susceptibility to imipenem and macrophages.

PubMed

Lima, Flavia Luna; Joazeiro, Paulo Pinto; Lancellotti, Marcelo; de Hollanda, Luciana Maria; de Araújo Lima, Bruna; Linares, Edlaine; Augusto, Ohara; Brocchi, Marcelo; Giorgio, Selma

2015-01-01

The seriousness to treat burn wounds infected with Pseudomonas aeruginosa led us to examine whether the effect of the carbapenem antibiotic imipenem is enhanced by hyperbaric oxygen (HBO). The effects of HBO (100% O2, 3 ATA, 5 h) in combination with imipenen on bacterial counts of six isolates of P. aeruginosa and bacterial ultrastructure were investigated. Infected macrophages were exposed to HBO (100% O2, 3 ATA, 90 min) and the production of reactive oxygen species monitored. HBO enhanced the effects of imipenen. HBO increased superoxide anion production by macrophages and likely kills bacteria by oxidative mechanisms. HBO in combination with imipenem can be used to kill P. aeruginosa in vitro and such treatment may be beneficial for the patients with injuries containing the P. aeruginosa.

Hyperbaric oxygen therapy ameliorates acute brain injury after porcine intracerebral hemorrhage at high altitude.

PubMed

Zhu, Hai-tao; Bian, Chen; Yuan, Ji-chao; Liao, Xiao-jun; Liu, Wei; Zhu, Gang; Feng, Hua; Lin, Jiang-kai

2015-06-15

Intracerebral hemorrhage (ICH) at high altitude is not well understood to date. This study investigates the effects of high altitude on ICH, and examines the acute neuroprotection of hyperbaric oxygen (HBO) therapy against high-altitude ICH. Minipigs were placed in a hypobaric chamber for 72 h before the operation. ICH was induced by an infusion of autologous arterial blood (3 ml) into the right basal ganglia. Animals in the high-altitude ICH group received HBO therapy (2.5 ATA for 60 min) 30 min after ICH. Blood gas, blood glucose and brain tissue oxygen partial pressure (PbtO2) were monitored continuously for animals from all groups, as were microdialysis products including glucose, lactate, pyruvate and glutamate in perihematomal tissue from 3 to 12 h post-ICH. High-altitude ICH animals showed significantly lower PbtO2, higher lactate/pyruvate ratio (LPR) and glutamate levels than low-altitude ICH animals. More severe neurological deficits, brain edema and neuronal damage were also observed in high-altitude ICH. After HBO therapy, PbtO2 was significantly increased and LPR and glutamate levels were significantly decreased. Brain edema, neurological deficits and neuronal damage were also ameliorated. The data suggested a more serious disturbance of tissue oxygenation and cerebral metabolism in the acute stage after ICH at high altitude. Early HBO treatment reduced acute brain injury, perhaps through a mechanism involving the amelioration of the derangement of cerebral oxygenation and metabolism following high-altitude ICH.

Pilot case study of the therapeutic potential of hyperbaric oxygen therapy on chronic brain injury.

PubMed

Hardy, Paule; Johnston, Karen M; De Beaumont, Louis; Montgomery, David L; Lecomte, Jacqueline M; Soucy, Jean-Paul; Bourbonnais, Daniel; Lassonde, Maryse

2007-02-15

Recently, the effect of hyperbaric oxygen (HBO(2)) therapy was explored in the treatment of chronic TBI. It has been speculated that idling neurons in the penumbra zone remain viable several years after injury and might be reactivated by enhanced oxygenation. We studied the therapeutic potential of HBO(2) therapy in a 54-year-old man who had sustained traumatic brain injuries one year before testing that resulted in permanent neurological symptoms. Two treatment series separated by a one-year inter-session interval were administered. Treatment series consisted of 20 and 60 daily one-hour exposures to 100% oxygen at 2 ATA. Electrophysiological (event-related potentials), metabolic and behavioral (sensorimotor and neuropsychological) measurements were obtained to evaluate the effects of hyperbaric oxygen therapy on neurocognitive functioning. Following the initial treatment, the patient showed improvements in sensorimotor functions, as well as enhanced P300 amplitude in the damaged hemisphere. Although most of these gains were no longer observed one year after treatment, these were reinstated with an additional series of 60 exposures. Neuropsychological improvements were also observed after the completion of the second series of treatments. The present single-case study provides preliminary evidence of neuropsychological and electrophysiological improvements after series of 20 and 60 treatments, although the first dosage appeared to be insufficient to produce permanent benefits. Longitudinal studies using different treatment parameters should be conducted if we are to systematically investigate long-term improvements resulting from HBO(2) therapy.

Multivariate analysis of prognostic factors for idiopathic sudden sensorineural hearing loss treated with adjuvant hyperbaric oxygen therapy.

PubMed

Xie, Shaobing; Qiang, Qingfen; Mei, Lingyun; He, Chufeng; Feng, Yong; Sun, Hong; Wu, Xuewen

2018-01-01

The objective of this study is to evaluate possible prognostic factors of idiopathic sudden sensorineural hearing loss (ISSNHL) treated with adjuvant hyperbaric oxygen therapy (HBOT) using univariate and multivariate analyses. From January 2008 to October 2016, records of 178 ISSNHL patients treated with auxiliary hyperbaric oxygen therapy were reviewed to assess hearing recovery and evaluate associated prognostic factors (gender, age, localization, initial hearing threshold, presence of tinnitus, vertigo, ear fullness, hypertension, diabetes, onset of HBOT, number of HBOT, and audiogram), by using univariate and multivariate analyses. The overall recovery rate was 37.1%, including complete recovery (19.7%) and partial recovery (17.4%). According to multivariate analysis, later onset of HBOT and higher initial hearing threshold were associated with a poor prognosis in ISSNHL patients treated with HBOT. HBOT is a safe and beneficial adjuvant therapy for ISSNHL patients. 20 sessions of HBOT is possibly enough to show its therapeutic effect. Earlier HBOT onset and lower initial hearing threshold is associated with favorable hearing recovery.

Tinnitus, a military epidemic: is hyperbaric oxygen therapy the answer?

PubMed

Baldwin, Thomas M

2009-01-01

Tinnitus is the phantom perception of sound in the absence of overt acoustic stimulation. Its impact on the military population is alarming. Annually, tinnitus is the most prevalent disability among new cases added to the Veterans Affairs numbers. Also, it is currently the most common disability from the War on Terror. Conventional medical treatments for tinnitus are well documented, but prove to be unsatisfying. Hyperbaric oxygen (HBO2) therapy may improve tinnitus, but the significance of the level of improvement is not clear. There is a case for large randomized trials of high methodological rigor in order to define the true extent of the benefit with the administration of HBO2 therapy for tinnitus.

21 CFR 868.5470 - Hyperbaric chamber.

Code of Federal Regulations, 2013 CFR

2013-04-01

... hyperbaric chamber is a device that is intended to increase the environmental oxygen pressure to promote the movement of oxygen from the environment to a patient's tissue by means of pressurization that is greater than atmospheric pressure. This device does not include topical oxygen chambers for extremities (§ 878...

21 CFR 868.5470 - Hyperbaric chamber.

Code of Federal Regulations, 2014 CFR

2014-04-01

... hyperbaric chamber is a device that is intended to increase the environmental oxygen pressure to promote the movement of oxygen from the environment to a patient's tissue by means of pressurization that is greater than atmospheric pressure. This device does not include topical oxygen chambers for extremities (§ 878...

21 CFR 868.5470 - Hyperbaric chamber.

Code of Federal Regulations, 2012 CFR

2012-04-01

... hyperbaric chamber is a device that is intended to increase the environmental oxygen pressure to promote the movement of oxygen from the environment to a patient's tissue by means of pressurization that is greater than atmospheric pressure. This device does not include topical oxygen chambers for extremities (§ 878...

21 CFR 868.5470 - Hyperbaric chamber.

Code of Federal Regulations, 2011 CFR

2011-04-01

... hyperbaric chamber is a device that is intended to increase the environmental oxygen pressure to promote the movement of oxygen from the environment to a patient's tissue by means of pressurization that is greater than atmospheric pressure. This device does not include topical oxygen chambers for extremities (§ 878...

21 CFR 868.5470 - Hyperbaric chamber.

Code of Federal Regulations, 2010 CFR

2010-04-01

... hyperbaric chamber is a device that is intended to increase the environmental oxygen pressure to promote the movement of oxygen from the environment to a patient's tissue by means of pressurization that is greater than atmospheric pressure. This device does not include topical oxygen chambers for extremities (§ 878...

Hyperbaric oxygen treatment for air or gas embolism.

PubMed

Moon, R E

2014-01-01

Gas can enter arteries (arterial gas embolism) due to alveolar-capillary disruption (caused by pulmonary overpressurization, e.g., breath-hold ascent by divers) or veins (venous gas embolism, VGE) as a result of tissue bubble formation due to decompression (diving, altitude exposure) or during certain surgical procedures where capillary hydrostatic pressure at the incision site is sub-atmospheric. Both AGE and VGE can be caused by iatrogenic gas injection. AGE usually produces strokelike manifestations, such as impaired consciousness, confusion, seizures and focal neurological deficits. Small amounts of VGE are often tolerated due to filtration by pulmonary capillaries. However, VGE can cause pulmonary edema, cardiac "vapor lock" and AGE due to transpulmonary passage or right-to-left shunt through a patent foramen ovale. Intravascular gas can cause arterial obstruction or endothelial damage and secondary vasospasm and capillary leak. Vascular gas is frequently not visible with radiographic imaging, which should not be used to exclude the diagnosis of AGE. Isolated VGE usually requires no treatment; AGE treatment is similar to decompression sickness (DCS), with first aid oxygen then hyperbaric oxygen. Although cerebral AGE (CAGE) often causes intracranial hypertension, animal studies have failed to demonstrate a benefit of induced hypocapnia. An evidence-based review of adjunctive therapies is presented.

Free radical generation in the brain precedes hyperbaric oxygen-induced convulsions.

PubMed

Torbati, D; Church, D F; Keller, J M; Pryor, W A

1992-01-01

We tested the hypothesis that hyperbaric oxygenation (HBO) generates free radicals in the brain before the onset of neurological manifestations of central nervous system (CNS) oxygen poisoning. Chronically cannulated, conscious rats were individually placed in a transparent pressure chamber and exposed to (1) 5 atmospheres absolute (ATA) oxygen for 15 min (n = 4); (2) 5 ATA oxygen for 30 min (n = 5), during which no visible convulsions occurred; (3) 5 ATA oxygen for 30 min with recurrent convulsions (n = 6); (4) 5 ATA oxygen until the appearance of the first visible convulsions (n = 5); (5) 4 ATA oxygen for 60 min during which no convulsions occurred (n = 5); and (6) 5 ATA air for 30 min (n = 5, controls). Immediately before compression, 1 mL of 0.1 M of alpha-phenyl-N-tert-butyl nitrone (PBN) was administered intravenously (iv) for spin trapping. At the termination of each experiment, rats were euthanized by pentobarbital iv and decompressed within 1 min. Brains were rapidly removed for preparation of lipid extracts (Folch). The presence of PBN spin adducts in the lipid extracts was examined by electron spin resonance (ESR) spectroscopy. ESR spectra from unconvulsed rats exposed to 5 ATA oxygen for 30 min revealed both oxygen-centered and carbon-centered PBN spin adducts in three of the five brains. One of the five rats in this group showed an ascorbyl signal in the ESR spectrum.(ABSTRACT TRUNCATED AT 250 WORDS)

Selection criteria utilized for hyperbaric oxygen treatment of carbon monoxide poisoning.

PubMed

Hampson, N B; Dunford, R G; Kramer, C C; Norkool, D M

1995-01-01

Medical directors of North American hyperbaric oxygen (HBO) facilities were surveyed to assess selection criteria applied for treatment of acute carbon monoxide (CO) poisoning within the hyperbaric medicine community. Responses were received from 85% of the 208 facilities in the United States and Canada. Among responders, 89 monoplace and 58 multiplace chamber facilities treat acute CO poisoning, managing a total of 2,636 patients in 1992. A significant majority of facilities treat CO-exposed patients with coma (98%), transient loss of consciousness (LOC) (77%), ischemic changes on electrocardiogram (91%), focal neurologic deficits (94%), or abnormal psychometric testing (91%), regardless of carboxyhemoglobin (COHb) level. Although 92% would use HBO for a patient presenting with headache, nausea, and COHb 40%, only 62% of facilities utilize a specified minimum COHb level as the sole criterion for HBO therapy of an asymptomatic patient. When COHb is used as an independent criterion to determine HBO treatment, the level utilized varies widely between institutions. Half of responding facilities place limits on the delay to treatment for patients with only transient LOC. Time limits are applied less often in cases with persistent neurologic deficits. While variability exists, majority opinions can be derived for many patient selection criteria regarding the use of HBO in acute CO poisoning.

The influence of a hyperbaric environment and increased oxygen partial pressure on the corrosion of dental alloys.

PubMed

Mehl, Christian; Heblich, Frank; Lenz, Rudolf; Ludwig, Klaus; Kern, Matthias

2011-09-01

The purpose of this in-vitro study was to determine whether there is a correlation between a hyperbaric environment or increased oxygen partial pressure and the corrosion of dental alloys used for dental restorations in divers. Samples of three commercially available dental alloys (palladium-based, reduced-gold-content and high-gold-content) were tested in the DIN EN ISO 1562 static immersion test and the amount of dissolved ions measured by atomic absorption spectrometry. The specimens were exposed to one of the following three conditions: normobaric and normoxic conditions (PO2 21 kPa); 608 kPa (6 bar, PO2 127 kPa) pressurised air in a pressure chamber or 506 kPa (5 bar, PO2 304 kPa) pressurised nitrox in a pressure chamber. None of the exposures suggested a correlation between increased ion solubility as a measure of corrosion and increased ambient pressure of the three alloys. The reduced-gold-content alloy released zinc ions at twice the weekly recommended dose. When the palladium-based alloy was exposed to a hyperbaric or hyperbaric/hyperoxic environment, ion solubility increased only slightly for gallium and silver. Within the limited sample size of the current study it can be concluded that hyperbaric and/or hyperoxic conditions do not seem to be a risk for increased corrosion for any of the three tested alloys.

Effects of Hyperbaric Oxygen Treatment on Renal System.

PubMed

Tezcan, Orhan; Caliskan, Ahmet; Demirtas, Sinan; Yavuz, Celal; Kuyumcu, Mahir; Nergiz, Yusuf; Guzel, Abdulmenap; Karahan, Oguz; Ari, Seyhmus; Soker, Sevda; Yalinkilic, Ibrahim; Turkdogan, Kenan Ahmet

2017-01-01

Hyperbaric oxygen (HBO) treatment is steadily increasing as a therapeutic modality for various types of diseases. Although good clinical outcomes were reported with HBO treatment for various diseases, the multisystemic effects of this modality are still unclear. This study aimed to investigate the renal effects of HBO experimentally. Fourteen New Zealand White rabbits were divided into 2 groups randomly as the control group and the study group. The study group received HBO treatment for 28 days (100% oxygen at 2.5 atmospheres for 90 minutes daily) and the control group was used to obtain normal renal tissue of the animal genus. After the intervention period, venous blood samples were obtained, and renal tissue samples were harvested for comparisons. Normal histological morphology was determined with Masson trichrome staining and periodic acid-Schiff staining in the control group. Atrophic glomerular structures, vacuolated tubule cells, and degeneration were detected in the renal samples of the study group with Masson trichrome staining. Additionally, flattening was observed on the brush borders of the proximal tubules, and tubular dilatation was visualized with periodic acid-Schiff staining. The histopathologic disruption of renal morphology was verified with detection of significantly elevated kidney function laboratory biomarkers in the study group. Our findings suggests that HBO has adverse effects on renal glomerulus and proximal tubules. However, the functional effects of this alteration should be investigated with further studies.

Improvement of attention span and reaction time with hyperbaric oxygen treatment in patients with toxic injury due to mold exposure.

PubMed

Ezra, N; Dang, K; Heuser, G

2011-01-01

It is, by now, well established that mold toxins (mycotoxins) can cause significant adverse health effects. In this study, 15 subjects who developed an attention deficit disorder (ADD) and slowing of reaction time at the time of exposure to mold toxins were identified. Deficits in attention span and reaction time were documented not only by taking a careful history, but also by performing a Test of Variables of Attention (TOVA). The TOVA test provides an objective measure of these two variables. It was found that mold-exposed subjects show statistically significant decreases in attention span and significant increases in reaction time to stimuli compared to controls. After ten sessions of hyperbaric oxygen treatment (HBOT), a statistically significant improvement was seen in both measures. This preliminary study suggests promising outcomes in treating mold-exposed patients with hyperbaric oxygen.

Improvement of attention span and reaction time with hyperbaric oxygen treatment in patients with toxic injury due to mold exposure

PubMed Central

Ezra, N.; Dang, K.

2010-01-01

It is, by now, well established that mold toxins (mycotoxins) can cause significant adverse health effects. In this study, 15 subjects who developed an attention deficit disorder (ADD) and slowing of reaction time at the time of exposure to mold toxins were identified. Deficits in attention span and reaction time were documented not only by taking a careful history, but also by performing a Test of Variables of Attention (TOVA). The TOVA test provides an objective measure of these two variables. It was found that mold-exposed subjects show statistically significant decreases in attention span and significant increases in reaction time to stimuli compared to controls. After ten sessions of hyperbaric oxygen treatment (HBOT), a statistically significant improvement was seen in both measures. This preliminary study suggests promising outcomes in treating mold-exposed patients with hyperbaric oxygen. PMID:20978814

Combined Hyperbaric Oxygen Partial Pressure at 1.4 Bar with Infrared Radiation: A Useful Tool To Improve Tissue Hypoxemia?

PubMed

Dünnwald, Tobias; Held, Julia; Balan, Petru; Pecher, Otto; Zeiger, Thomas; Hartig, Frank; Mur, Erich; Weiss, Günter; Schobersberger, Wolfgang

2018-06-13

Tissue hypoxia contributes to the pathogenesis of several acute and chronic diseases. Hyperbaric oxygen therapy (HBO) and whole-body warming using low-temperature infrared technology (LIT) are techniques that might improve hypoxemia. Combining HBO and LIT as hyperbaric oxygen therapy combined with low-temperature infrared radiation (HBOIR) might be an approach that results in positive synergistic effects on oxygenation. LIT increases blood flow and could reduce HBO-induced vasoconstriction, and hyperoxia could compensate for the increased metabolic oxygen requirements mediated by LIT. Both LIT and HBO increase the oxygen diffusion distance in the tissues. HBOIR at 0.5 bar has been shown to be safe and feasible. However, physiological responses and the safety of HBOIR at an increased oxygen (O2) partial pressure of 1.4 bar or 2.4 atmospheres absolute (ATA) still need to be determined. The hope is that should HBOIR at an increased oxygen partial pressure of 1.4 bar be safe, future studies to examine its efficacy in patients with clinical conditions, which include peripheral arterial disease (PAD) or wound healing disorders, will follow. The results of pilot studies have shown that HBOIR at an overload pressure is safe and well tolerated in healthy participants but can generate moderate cardiovascular changes and an increase in body temperature. From the findings of this pilot study, due to its potential synergistic effects, HBOIR could be a promising tool for the treatment of human diseases associated with hypoxemia.

Microvascular oxygen partial pressure during hyperbaric oxygen in diabetic rat skeletal muscle.

PubMed

Yamakoshi, Kohei; Yagishita, Kazuyoshi; Tsuchimochi, Hirotsugu; Inagaki, Tadakatsu; Shirai, Mikiyasu; Poole, David C; Kano, Yutaka

2015-12-15

Hyperbaric oxygen (HBO) is a major therapeutic treatment for ischemic ulcerations that perforate skin and underlying muscle in diabetic patients. These lesions do not heal effectively, in part, because of the hypoxic microvascular O2 partial pressures (PmvO2 ) resulting from diabetes-induced cardiovascular dysfunction, which alters the dynamic balance between O2 delivery (Q̇o2) and utilization (V̇o2) rates. We tested the hypothesis that HBO in diabetic muscle would exacerbate the hyperoxic PmvO2 dynamics due, in part, to a reduction or slowing of the cardiovascular, sympathetic nervous, and respiratory system responses to acute HBO exposure. Adult male Wistar rats were divided randomly into diabetic (DIA: streptozotocin ip) and healthy (control) groups. A small animal hyperbaric chamber was pressurized with oxygen (100% O2) to 3.0 atmospheres absolute (ATA) at 0.2 ATA/min. Phosphorescence quenching techniques were used to measure PmvO2 in tibialis anterior muscle of anesthetized rats during HBO. Lumbar sympathetic nerve activity (LSNA), heart rate (HR), and respiratory rate (RR) were measured electrophysiologically. During the normobaric hyperoxia and HBO, DIA tibialis anterior PmvO2 increased faster (mean response time, CONT 78 ± 8, DIA 55 ± 8 s, P < 0.05) than CONT. Subsequently, PmvO2 remained elevated at similar levels in CONT and DIA muscles until normobaric normoxic recovery where the DIA PmvO2 retained its hyperoxic level longer than CONT. Sympathetic nervous system and cardiac and respiratory responses to HBO were slower in DIA vs. CONT. Specifically the mean response times for RR (CONT: 6 ± 1 s, DIA: 29 ± 4 s, P < 0.05), HR (CONT: 16 ± 1 s, DIA: 45 ± 5 s, P < 0.05), and LSNA (CONT: 140 ± 16 s, DIA: 247 ± 34 s, P < 0.05) were greater following HBO onset in DIA than CONT. HBO treatment increases tibialis anterior muscle PmvO2 more rapidly and for a longer duration in DIA than CONT, but not to a greater level. Whereas respiratory, cardiovascular

Hyperbaric oxygen for post-concussive symptoms in United States military service members: a randomized clinical trial.

PubMed

Weaver, Lindell K; Wilson, Steffanie H; Lindblad, Anne S; Churchill, Susan; Deru, Kayla; Price, Robert C; Williams, Chris S; Orrison, William W; Walker, James M; Meehan, Anna; Mirow, Susan

2018-01-01

In prior military randomized trials, participants with persistent symptoms after mild traumatic brain injury (TBI) reported improvement regardless of receiving hyperbaric oxygen (HBO₂) or sham intervention. This study's objectives were to identify outcomes for future efficacy trials and describe changes by intervention. This Phase II, randomized, double-blind, sham-controlled trial enrolled military personnel with mild TBI and persistent post-concussive symptoms. Participants were randomized to receive 40 HBO₂ (1.5 atmospheres absolute (ATA), ⟩99% oxygen, 60 minutes) or sham chamber sessions (1.2 ATA, room air, 60 minutes) over 12 weeks. Participants and evaluators were blinded to allocation. Outcomes assessed at baseline, 13 weeks and six months included symptoms, quality of life, neuropsychological, neurological, electroencephalography, sleep, auditory, vestibular, autonomic, visual, neuroimaging, and laboratory testing. Participants completed 12-month questionnaires. Intention-to-treat results are reported. From 9/11/2012 to 5/19/2014, 71 randomized participants received HBO₂ (n=36) or sham (n=35). At baseline, 35 participants (49%) met post-traumatic stress disorder (PTSD) criteria. By the Neurobehavioral Symptom Inventory, the HBO₂ group had improved 13-week scores (mean change -3.6 points, P=0.03) compared to sham (+3.9 points). In participants with PTSD, change with HBO₂ was more pronounced (-8.6 vs. +4.8 points with sham, P=0.02). PTSD symptoms also improved in the HBO₂ group, and more so in the subgroup with PTSD. Improvements regressed at six and 12 months. Hyperbaric oxygen improved some cognitive processing speed and sleep measures. Participants with PTSD receiving HBO₂ had improved functional balance and reduced vestibular complaints at 13 weeks. By 13 weeks, HBO₂ improved post-concussive and PTSD symptoms, cognitive processing speed, sleep quality, and balance function, most dramatically in those with PTSD. Changes did not persist

Characterization of the Effects of Hyperbaric Oxygen on the Biochemical and Optical Properties of the Bovine Lens.

PubMed

Lim, Julie C; Vaghefi, Ehsan; Li, Bo; Nye-Wood, Mitchell G; Donaldson, Paul J

2016-04-01

To assess the morphologic, biochemical, and optical properties of bovine lenses treated with hyperbaric oxygen. Lenses were exposed to hyperbaric nitrogen (HBN) or hyperbaric oxygen (HBO) for 5 or 15 hours, lens transparency was assessed using bright field microscopy and lens morphology was visualized using confocal microscopy. Lenses were dissected into the outer cortex, inner cortex, and core, and glutathione (GSH) and malondialdehyde (MDA) measured. Gel electrophoresis and Western blotting were used to detect high molecular weight aggregates (HMW) and glutathione mixed protein disulfides (PSSG). T2-weighted MRI was used to measure lens geometry and map the water/protein ratio to allow gradient refractive index (GRIN) profiles to be calculated. Optical modeling software calculated the change in lens optical power, and an anatomically correct model of the light pathway of the bovine eye was used to determine the effects of HBN and HBO on focal length and overall image quality. Lenses were transparent and lens morphology similar between HBN- and HBO-treated lenses. At 5- and 15-hour HBO exposure, GSH and GSSG were depleted and MDA increased in the core. Glutathione mixed protein disulfides were detected in the outer and inner cortex only with no appearance of HMW. Optical changes were detectable only with 15-hour HBO treatment with a decrease in the refractive index of the core, slightly reduced lens thickness, and an increase in optimal focal length, consistent with a hyperopic shift. This system may serve as a model to study changes that occur with advanced aging rather than nuclear cataract formation per se.

Review of recent non-hyperbaric oxygen interventions for mild traumatic brain injury.

PubMed

Wilson, Steffanie H; Roth, Michael; Lindblad, Anne S; Weaver, Lindell K

2016-01-01

Traumatic brain injury (TBI) affects 3.2 to 5.3 million persons in the United States (U.S.), and the impact in the U.S. military is proportionally higher. Consensus is lacking regarding an accepted outcome to measure the effectiveness of interventions to improve the symptoms associated with TBI, and no standard-of-care treatment exists for mild TBI (mTBI). A recent literature review evaluated hyperbaric oxygen therapy (HBO₂) interventions, and findings were mixed. We conducted a systematic review of non-HBO₂ mTBI interventional trials published in 2005-2015 in military and civilian populations. A total of 154 abstracts, seven randomized controlled trials (RCTs) and five pilot studies were reviewed. RCTs were evaluated using Consolidated Standards of Reporting Trials criteria. Results indicated that studies published within the period of review were small pilot studies for rehabilitation therapy and motion capture or virtual reality gaming interventions. Neuropsychological assessments were commonly specified outcomes, and most studies included a combination of symptom and neuropsychological assessments. Findings indicated a lack of large-scale, well-controlled trials to address the symptoms and sequelae of this condition, but results of small exploratory studies show evidence of potentially promising interventions. Copyright© Undersea and Hyperbaric Medical Society.

Does hyperbaric oxygen have a cancer-causing or -promoting effect? A review of the pertinent literature.

PubMed

Feldmeier, J J; Heimbach, R D; Davolt, D A; Brakora, M J; Sheffield, P J; Porter, A T

1994-12-01

We reviewed all known published reports or studies related to a possible cancer-causing or growth-enhancing effect by hyperbaric oxygen. Published articles were retrieved using Medline searches for the period 1960-1993. Additional references were obtained from bibliographies included in those articles discovered in the computer search. Also, hyperbaric medicine text books and the published proceedings of international hyperbaric conferences were visually searched. Studies and reports discovered in this fashion and related to the topic were included in the review. Twenty-four references were found: 12 were clinical reports, 11 were animal studies, and 1 reported both an animal study and a clinical report. Three clinical reports suggested a positive cancer growth enhancement, whereas 10 clinical reports showed no cancer growth enhancement. Two animal studies suggested a positive cancer-enhancing effect, and 10 animal studies showed no such effect. (The report that included both animals and humans is counted in both groups). The vast majority of published reports show no cancer growth enhancement by HBO exposure. Those studies that do show growth enhancement are refuted by larger subsequent studies, are mixed studies, or are highly anecdotal. A review of published information fails to support a cancer-causing or growth-enhancing effect by HBO.

Hyperbaric oxygen therapy in the pediatric patient: the experience of the Israel Naval Medical Institute.

PubMed

Waisman, D; Shupak, A; Weisz, G; Melamed, Y

1998-11-01

The pediatric patient is to be found in hyperbaric facilities throughout the world, receiving hyperbaric oxygen (HBO) therapy for both life-threatening and chronic diseases. To review the experience accumulated at the Israel Naval Medical Institute in the treatment of pediatric patients. A retrospective analysis and review of all records of patients younger than age 18 years. Between 1980 and 1997, 139 pediatric patients age 2 months to 18 years (mean, 7.7 years) received HBO treatment at the Israel Naval Medical Institute. Of the children, 111 (79%) suffered from acute carbon monoxide (CO) poisoning; 13 (9.2%) were treated after crush injury, traumatic ischemia, or compartment syndrome; 4 (2.8%) had clostridial myonecrosis; 1 (0.7%) had necrotizing fasciitis; 5 (3.6%) had refractory osteomyelitis; 2 (1.4%) had suffered massive air embolism; 2 (1.4%) had purpura fulminans; and 1 (0.7%) suffered from decompression sickness. Outcome, judged by neurologic sequelae, mortality, and extent of soft tissue loss and limb amputation, was favorable in 129 patients (93%). Two patients (1.4%) died, 1 as a result of CO poisoning and the other, gas gangrene; 2 of the patients in the CO group (1.4%) remained with neurologic sequelae, and 6 patients in the acute traumatic ischemia group (4.3%) underwent limb amputation. We had a favorable experience with 129 of a total 139 pediatric patients treated at our facility for the indications listed. A basic knowledge of HBO therapy is needed to refer the pediatric patient for treatment when indicated. The needs of the pediatric patient, especially the critically ill, require specific skills and equipment inside the hyperbaric chamber. Close collaboration between the pediatrician and the hyperbaric medicine physician is essential to ensure adequate care for infants and children.

Research Report: Intermittent hypobaric hypoxia and hyperbaric oxygen on GAP-43 in the rat carotid body.

PubMed

Peng, Zhengwu; Fan, Juan; Liu, Ling; Kuang, Fang; Xue, Fen; Wang, Bairen

2015-01-01

Adaptive changes in the carotid body (CB) including the expression of the growth-associated protein-43 (GAP-43) have been studied in response to low, but not high, oxygen exposure. Expression of GAP-43 in the CB of rats under different atmospheric pressures and oxygen partial pressure (PO2) conditions was investigated. Mature male Sprague-Dawley rats were exposed to intermittent hypobaric hypoxia (IHH, 0, 1, 2 and 3 weeks), intermittent hyperbaric oxygen (IHBO2, 0, 1, 5 and 10 days, sacrificed six hours or 24 hours after the last HBO2 exposure), and intermittent hyperbaric normoxia (IHN, same treatment pattern as IHBO2). GAP-43 was highly expressed (mainly in type I cells) in the CB of normal rats. IHH u-regulated GAP-43 expression in the CB with significant differences (immunohistochemical staining [IHC]: F(3,15)=40.64, P < 0.01; western blot [WB]: F(3,16) = 53.52, P < 0.01) across the subgroups. GAP-43 expression in the CB was inhibited by IHBO2 (controls vs. IHBO2 groups, IHC: F(6,30) = 15.85, P < 0.01; WB: F(6,29) = 15.95, P < 0.01). No detectable changes in GAP-43 expression were found for IHN. These findings indicated that different PO2 conditions, but not air pressures, played an important role in the plasticity of the CB, and that GAP-43 might be a viable factor for the plasticity of the CB.

Management of vibration sickness in coal mines by hyperbaric oxygenation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soboleva, N.P.

1985-02-01

Clinical trials were conducted with hyperbaric oxygenation in the management of vibration sickness in 30 coal miners, 42 to 47 years of age. Assessment of the results of symptomatology and objective laboratory criteria (tetrapolar finger rheography, occulsion plethysmography) demonstrate market improvements in the treated subjects. Headaches disappeared or diminished in intensity, irritability, and fatigability became less pronounced, sleep improved, and the emotional status of the workers provided additional confirmation of the salubrious effects. Among the more pronounced objective findings were the increase in the filling volume and in the blood flow of the peripheral vasculature, and a three-fold decrease inmore » peripheral vascular resistance (from 97 + or 18.2 mm/m1/100 g/min in untreated controls, to 29.0 + or - 6.4 mm/ml/100 g/min in the treated subjects).« less

Adjunctive Hyperbaric Oxygen Therapy for Healing of Chronic Diabetic Foot Ulcers: A Randomized Controlled Trial.

PubMed

Chen, Chen-Yu; Wu, Re-Wen; Hsu, Mei-Chi; Hsieh, Ching-Jung; Chou, Man-Chun

The purpose of this study was to compare the effect of standard wound care with adjunctive hyperbaric oxygen therapy (HBOT) to standard wound care alone on wound healing, markers of inflammation, glycemic control, amputation rate, survival rate of tissue, and health-related quality of life in patients with diabetic foot ulcers (DFUs). Prospective, randomized, open-label, controlled study. The sample comprised 38 patients with nonhealing DFUs who were deemed poor candidates for vascular surgery. Subjects were randomly allocated to an experimental group (standard care plus HBOT, n = 20) or a control group (standard care alone, n = 18). The study setting was a medical center in Kaohsiung City, Taiwan. Hyperbaric oxygen therapy was administered in a hyperbaric chamber under 2.5 absolute atmospheric pressure for 120 minutes; subjects were treated 5 days a week for 4 consecutive weeks. Both groups received standard wound care including debridement of necrotic tissue, topical therapy for Wagner grade 2 DFUs, dietary control and pharmacotherapy to maintain optimal blood glucose levels. Wound physiological indices were measured and blood tests (eg, markers of inflammation) were undertaken. Health-related quality of life was measured using the Medical Outcomes Study 36-Item Short Form. Complete DFU closure was achieved in 5 patients (25%) in the HBOT group (n = 20) versus 1 participant (5.5%) in the routine care group (n = 18) (P = .001). The amputation rate was 5% for the HBOT group and 11% for the routine care group (χ = 15.204, P = .010). The HBOT group showed statistically significant improvements in inflammation index, blood flow, and health-related quality of life from pretreatment to 2 weeks after the last therapy ended (P < .05). Hemoglobin A1c was significantly lower in the HBOT group following treatment (P < .05) but not in the routine care group. Adjunctive HBOT improved wound healing in persons with DFU. Therapy also reduced the risk of amputation of the

Hyperbaric oxygen therapy for wound healing in diabetic rats: Varying efficacy after a clinically-based protocol

PubMed Central

van Neck, Johan W.; Tuk, Bastiaan; Fijneman, Esther M. G.; Redeker, Jonathan J.; Talahatu, Edwin M.; Tong, Miao

2017-01-01

Hyperbaric oxygen therapy (HBOT) is a clinical treatment in which a patient breathes pure oxygen for a limited period of time at an increased pressure. Although this therapy has been used for decades to assist wound healing, its efficacy for many conditions is unproven and its mechanism of action is not yet fully clarified. This study investigated the effects of HBOT on wound healing using a diabetes-impaired pressure ulcer rat model. Seven weeks after streptozotocin-induced diabetes in rats (n = 55), a pressure ulcer was created on dorsal skin. Subsequently, animals received HBOT during 6 weeks following a standard clinical protocol (HBOT group with varying endpoints up to 42 days post-wounding) versus controls without HBOT. Capillary venous oxygen saturation (SO2) showed a significant increase in the HBOT group on day 24; however, this increase was significant at this time point only. The quantity of hemoglobin in the micro-blood vessels (rHB) showed a significant decrease in the HBOT group on days 21 and 42, and showed a trend to decrease on day 31. Blood flow in the microcirculation showed a significant increase on days 17, 21 and 31 but a significant decrease on days 24 and 28. Inflammation scoring showed significantly decreased CD68 counts in the HBOT group on day 42, but not in the early stages of wound healing. Animals in the HBOT group showed a trend for an increase in mean wound breaking strength on day 42. PMID:28545109

Wireless transmission of biosignals for hyperbaric chamber applications

PubMed Central

Perez-Vidal, Carlos; Gracia, Luis; Carmona, Cristian; Alorda, Bartomeu; Salinas, Antonio

2017-01-01

This paper presents a wireless system to send biosignals outside a hyperbaric chamber avoiding wires going through the chamber walls. Hyperbaric chambers are becoming more and more common due to new indications of hyperbaric oxygen treatments. Metallic walls physically isolate patients inside the chamber, where getting a patient’s vital signs turns into a painstaking task. The paper proposes using a ZigBee-based network to wirelessly transmit the patient's biosignals to the outside of the chamber. In particular, a wearable battery supported device has been designed, implemented and tested. Although the implementation has been conducted to transmit the electrocardiography signal, the device can be easily adapted to consider other biosignals. PMID:28296900

Hyperbaric Oxygen Therapy in the Treatment of Chronic Mild-Moderate Blast-Induced Traumatic Brain Injury PCS and PTSD

DTIC Science & Technology

2015-10-01

hyperbaric oxygen therapy; TBI: traumatic brain injury; PPCS: persistent post- concussion syndrome 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...persistent post- concussion syndrome (PPCS). Evidence-based medicine exists for PTSD, but there is no effective treatment for the persistent post... concussion syndrome (PPCS) of mild-moderate TBI nor the combined diagnoses of PPCS and PTSD. Between the Fall of 2008 and end of 2010, the P.I

Defense Health Care: Research on Hyperbaric Oxygen Therapy to Treat Traumatic Brain Injury and Post-Traumatic Stress Disorder

DTIC Science & Technology

2015-12-01

injuries that are not combat related. Letter Page 2 GAO-16-154 Hyperbaric Oxygen Therapy depression , and suicide. Experts believe...fatigue, visual disturbances, sensitivity to noise, judgment problems, depression , and anxiety. Although the majority of individuals with mild TBI have...suffer from other ailments, such as depression and substance abuse. PTSD is one of the most prevalent mental disorders arising from combat. HBO2

[Long-term effects of early hyperbaric oxygen therapy on neonatal rats with hypoxic-ischemic brain damage].

PubMed

Liu, Mei-Na; Zhuang, Si-Qi; Zhang, Hong-Yu; Qin, Zhao-Yuan; Li, Xiao-Yu

2006-06-01

The application and therapeutic effect of hyperbaric oxygen (HBO) in hypoxic-ischemic brain damage (HIBD) remains controversial. Previous studies have focused on the early pathological and biochemical outcomes and there is a lack of long-term functional evaluation. This study was designed to evaluate the long-term pathological and behavioral changes of early HBO therapy on neonatal rats with HIBD. Postnatal 7 days (PD7) rat pups were randomly assigned into Control (n=18), HIBD (n=17) and HBO treatment groups (n=17). HIBD was induced by ligating the left common carotid, followed by 2 hrs hypoxia exposure in the HIBD and HBO treatment groups. The Control group was sham-operated and was not subjected to hypoxia exposure. The HBO therapy with 2 atmosphere absolutes began 0.5-1 hr after HIBD in the HIBD treatment group, once daily for 2 days. The spatial learning and memory ability were evaluated by the Morris water maze test at PD37 to PD41. The morphological and histological changes of the brain, including brain weight, survival neurons, AchE positive unit and NOS positive neurons in hippocampal CA1 region, were detected at PD42. The rats in the HIBD group displayed significant morphological and histological deficits, as well as severe spatial learning and memory disability. In the Morris water maze test, the mean escape latency were longer (56.35 +/- 22.37 s vs 23.07 +/- 16.28 s; P < 0.05) and the probe time and probe length were shorter in the HIBD group (29.29 +/- 6.06 s vs 51.21 +/- 4.59 s and 548 +/- 92 cm vs 989 +/- 101 cm; both P < 0.05) compared with the Control group. The left brain weight in the HIBD group was lighter than that in the Control group (0.601 +/- 0.59 g vs 0.984 +/- 0.18 g; P < 0.05). The survival neurons in the hippocampal CA1 region were less (100 +/- 27/mm vs 183 +/- 8/mm; P < 0.05), as well as the AchE-positive unit and NOS-positive neurons (18.50 +/- 2.24% vs 27.50 +/- 2.18% and 19.25 +/- 4.33 vs 33.75 +/- 5.57 respectively; P < 0.05) after

Hyperbaric oxygen therapy may overcome nitric oxide blockage during cyanide intoxication.

PubMed

Polzik, Peter; Hansen, Marco Bo; Olsen, Niels Vidiendal; Grøndal, Olav; Hyldegaard, Ole

2017-01-01

To determine the effects of a blockade of nitric oxide (NO) synthesis on hyperbaric oxygen (HBO₂) therapy during cyanide (CN) intoxication. 39 anesthetized female Sprague-Dawley rats were exposed to CN intoxication (5.4 mg/kg intra-arterially) with or without previous nitric oxide synthase (NOS) inhibition by L-NG-nitroarginine methyl ester (L-NAME) injection (40 mg/kg intraperitoneally). Subsequently, either HBO₂ therapy (284 kPa/90 minutes), normobaric oxygen therapy (100% oxygen/90 minutes) or nothing was administered. Intracerebral microdialysis was used to measure the interstitial brain concentration of lactate, glucose, glycerol and lactate/pyruvate ratios. L-NAME potentiated CN intoxication by higher maximum and prolonged lactate (in mM: 0. 5 ± 0.3 vs. 0.7 ± 0.4, P ⟨ 0.005) concentrations compared with solely CN-intoxicated rats. The same trend was found for mean glucose, glycerol and lactate/pyruvate ratio levels. During HBO₂ treatment a sustained reduction occurred in mean lactate levels (in mM: 0.5 ± 0.5 vs. 0.7 ± 0.4, P ⟨ 0.01) regardless of NOS blockade by L-NAME. The same trend was found for mean glucose and glycerol levels. The results suggest that blocking NOS using L-NAME can worsen acute CN intoxication. HBO₂ treatment can partially overcome this block and continue to ameliorate CN intoxication.

UHMS position statement: topical oxygen for chronic wounds.

PubMed

Feldmeier, J J; Hopf, H W; Warriner, R A; Fife, C E; Gesell, L B; Bennett, M

2005-01-01

A small body of literature has been published reporting the application of topical oxygen for chronic non-healing wounds . Frequently, and erroneously, this form of oxygen administration has been referred to as "topical hyperbaric oxygen therapy" or even more erroneously "hyperbaric oxygen therapy." The advocates of topical oxygen claim several advantages over systemic hyperbaric oxygen including decreased cost, increased safety, decreased complications and putative physiologic effects including decreased free radical formation and more efficient delivery of oxygen to the wound surface. With topical oxygen an airtight chamber or polyethylene bag is sealed around a limb or the trunk by either a constriction/tourniquet device or by tape and high flow (usually 10 liters per minute) oxygen is introduced into the bag and over the wound. Pressures just over 1.0 atmospheres absolute (atm abs) (typically 1.004 to 1.013 atm abs) are recommended because higher pressures could decrease arterial/capillary inflow. The premise for topical oxygen, the diffusion of oxygen into the wound adequate to enhance healing, is attractive (though not proven) and its delivery is certainly less complex and expensive than hyperbaric oxygen. When discussing the physiology of topical oxygen, its proponents frequently reference studies of systemic hyperbaric oxygen suggesting that mechanisms are equally applicable to both topical and systemic high pressure oxygen delivery. In fact, however, the two are very different. To date, mechanisms of action whereby topical oxygen might be effective have not been defined or substantiated. Conversely, cellular toxicities due to extended courses of topical oxygen have been reported, although, again these data are not conclusive, and no mechanism for toxicity has been examined scientifically. Generally, collagen production and fibroblast proliferation are considered evidence of improved healing, and these are both enhanced by hyperbaric oxygen therapy

Effects of hyperbaric oxygen therapy in enhancing expressions of e-NOS, TNF-α and VEGF in wound healing

NASA Astrophysics Data System (ADS)

Susilo, Imam; Devi, Anita; Purwandhono, Azham; Hadi Warsito, Sunaryo

2017-05-01

Wound healing is a physiological process that occurs progressively through overlapping phases. Tissue oxygenation is an important part of the complex regulation for wound healing. Hyperbaric Oxygen (HBO) therapy is a method of increasing oxygen delivery to tissues. The therapy improves tissue oxygenation and stimulates the formation of H2O2 as a secondary messenger for Tumour Necrosis Factor alpha (TNF α), e-NOS, VEGF and Nuclear Factor Kappa Beta phosphorylation (NF-Kb) which play an important role in the rapid transcription of a wide variety of genes in response to extracellular stimuli. This study aims to determine the effects of Hyperbaric Oxygen therapy in enhancing the expressions of e-NOS, TNF-α, VEGF and wound healing. This study is an animal study with a ‘randomized control group of pre-test and post test design’ on 28 Wistar rats. Randomly, the rats were divided into 4 groups with 7 rats in each group. The HBO treatment group 1 received 5 sessions of HBO 2.4 ATA in 3 × 30 minutes; the HBO treatment group 2 received 10 sessions of HBO 2.4 ATA in 3 × 30 minutes; and each of the control groups were without HBO. Each of the 28 male rats were given a full thickness excisional wound of 1 × 1cm. Examinations of e-NOS, TNF-α, VEGF expressions and wound healing were performed on day-0 (pre-HBO) and day-5 HBO or on day-0 (pre-HBO) and day-10 HBO. The resultsshowthat the Hyperbaric Oxygen therapy can improve e-NOS (p=0.02), TNF-α (p= 0.02), VEGF expression (p=0.02) and wound healing (p=0.002) significantly in the provision of HBO 2.4 ATA for 3 × 30 minutes in 5 sessions over 5 consecutive days. While the 10 sessions of HBO 2.4 ATA for 3 × 30 minutes over 10 consecutive days only increase e-NOS (p=0.02), TNF-α (p=0.04), VEGF expression significantly (p=0.03) but do not improve wound healing significantly (p=0.3) compared with no HBO. The study concludes that HBO can improve the expressions of e-NOS, TNF-α, VEGF and wound healing in the provision of HBO

Bluetooth Communication Interface for EEG Signal Recording in Hyperbaric Chambers.

PubMed

Pastena, Lucio; Formaggio, Emanuela; Faralli, Fabio; Melucci, Massimo; Rossi, Marco; Gagliardi, Riccardo; Ricciardi, Lucio; Storti, Silvia F

2015-07-01

Recording biological signals inside a hyperbaric chamber poses technical challenges (the steel walls enclosing it greatly attenuate or completely block the signals as in a Faraday cage), practical (lengthy cables creating eddy currents), and safety (sparks hazard from power supply to the electronic apparatus inside the chamber) which can be overcome with new wireless technologies. In this technical report we present the design and implementation of a Bluetooth system for electroencephalographic (EEG) recording inside a hyperbaric chamber and describe the feasibility of EEG signal transmission outside the chamber. Differently from older systems, this technology allows the online recording of amplified signals, without interference from eddy currents. In an application of this technology, we measured EEG activity in professional divers under three experimental conditions in a hyperbaric chamber to determine how oxygen, assumed at a constant hyperbaric pressure of 2.8 ATA , affects the bioelectrical activity. The EEG spectral power estimated by fast Fourier transform and the cortical sources of the EEG rhythms estimated by low-resolution brain electromagnetic analysis were analyzed in three different EEG acquisitions: breathing air at sea level; breathing oxygen at a simulated depth of 18 msw, and breathing air at sea level after decompression.

Hyperbaric oxygen therapy with topical negative pressure: an alternative treatment for the refractory sternal wound infection.

PubMed

Sun, I-Feng; Lee, Su-Shin; Chiu, Chaw-Chi; Lin, Sin-Daw; Lai, Chung-Sheng

2008-01-01

Sternal osteomyelitis is a potentially lethal complication after cardiac surgery. It may be the cause of postoperative morbidity and mortality. We present a case of deep sternal wound infection after sternotomy. The patient received three treatments of surgical debridement, irrigation, topical negative pressure (TNP) dressing, and hyperbaric oxygen (HBO) therapy. Forty-five HBO therapy sessions were administered. After nine weeks, the sternal wound was healed and completely epithelialized. This conservative therapy can be an alternative and inexpensive method for the difficult sternal wound infection patient.

Evaluation of the Carefusion Alaris PC infusion pump for hyperbaric oxygen therapy conditions: Technical report.

PubMed

Smale, Andrew; Tsouras, Theo

2017-01-01

We present a standardized test methodology and results for our evaluation of the Carefusion Alaris PC infusion pump, comprising the model 8015 PC Unit and the model 8100 Large Volume Pump (LVP) module. The evaluation consisted of basic suitability testing, internal component inspection, surface temperature measurement of selected internal components, and critical performance testing (infusion rate accuracy and occlusion alarm pressure) during conditions of typical hyperbaric oxygen (HBO₂) treatment in our facility's class A multiplace chamber. We have found that the pumps pose no enhanced risk as an ignition source, and that the pumps operate within manufacturer's specifications for flow rate and occlusion alarms at all stages of HBO₂ treatments, up to 4.0 ATA and pressurization and depressurization rates up to 180 kPa/minute. The pumps do not require purging with air or nitrogen and can be used unmodified, subject to the following conditions: pumps are undamaged, clean, fully charged, and absent from alcohol cleaning residue; pumps are powered from the internal NiMH battery only; maximum pressure exposure 4.0 ATA; maximum pressurization and depressurization rate of 180 kPa/minute; LVP modules locked in place with retaining screws. Copyright© Undersea and Hyperbaric Medical Society.

The effects of hyperbaric oxygen therapy on oxidative stress, inflammation, and symptoms in children with autism: an open-label pilot study

PubMed Central

Rossignol, Daniel A; Rossignol, Lanier W; James, S Jill; Melnyk, Stepan; Mumper, Elizabeth

2007-01-01

Background Recently, hyperbaric oxygen therapy (HBOT) has increased in popularity as a treatment for autism. Numerous studies document oxidative stress and inflammation in individuals with autism; both of these conditions have demonstrated improvement with HBOT, along with enhancement of neurological function and cognitive performance. In this study, children with autism were treated with HBOT at atmospheric pressures and oxygen concentrations in current use for this condition. Changes in markers of oxidative stress and inflammation were measured. The children were evaluated to determine clinical effects and safety. Methods Eighteen children with autism, ages 3–16 years, underwent 40 hyperbaric sessions of 45 minutes duration each at either 1.5 atmospheres (atm) and 100% oxygen, or at 1.3 atm and 24% oxygen. Measurements of C-reactive protein (CRP) and markers of oxidative stress, including plasma oxidized glutathione (GSSG), were assessed by fasting blood draws collected before and after the 40 treatments. Changes in clinical symptoms, as rated by parents, were also assessed. The children were closely monitored for potential adverse effects. Results At the endpoint of 40 hyperbaric sessions, neither group demonstrated statistically significant changes in mean plasma GSSG levels, indicating intracellular oxidative stress appears unaffected by either regimen. A trend towards improvement in mean CRP was present in both groups; the largest improvements were observed in children with initially higher elevations in CRP. When all 18 children were pooled, a significant improvement in CRP was found (p = 0.021). Pre- and post-parental observations indicated statistically significant improvements in both groups, including motivation, speech, and cognitive awareness (p < 0.05). No major adverse events were observed. Conclusion In this prospective pilot study of children with autism, HBOT at a maximum pressure of 1.5 atm with up to 100% oxygen was safe and well tolerated

How to Get Hyperbaric Oxygen Therapy for Children with Cerebral Palsy or Brain Injury: Navigating Insurance Denials, Red Tape, and Other Challenges

ERIC Educational Resources Information Center

Console, Richard P., Jr.

2010-01-01

Medical professionals who use hyperbaric oxygen therapy (HBOT) say that recent studies, as well as anecdotal evidence, indicate that this treatment significantly improves the lives of many children with cerebral palsy and other types of chronic brain injury. So why do many children with these diagnoses not have access to this treatment? Simply…

Increased circulating stem cells and better cognitive performance in traumatic brain injury subjects following hyperbaric oxygen therapy.

PubMed

Shandley, Sabrina; Wolf, E George; Schubert-Kappan, Christine M; Baugh, Laura M; Richards, Michael F; Prye, Jennifer; Arizpe, Helen M; Kalns, John

2017-01-01

Traumatic brain injury (TBI) may cause persistent cognitive dysfunction. A pilot clinical study was performed to determine if hyperbaric oxygen (HBO₂) treatment improves cognitive performance. It was hypothesized that stem cells, mobilized by HBO₂ treatment, are recruited to repair damaged neuronal tissue. This hypothesis was tested by measuring the relative abundance of stem cells in peripheral blood and cognitive performance during this clinical trial. The subject population consisted of 28 subjects with persistent cognitive impairment caused by mild to moderate TBI suffered during military deployment to Iraq or Afghanistan. Fluorescence-activated cell sorting (FACS) analysis was performed for stem cell markers in peripheral blood and correlated with variables resulting from standard tests of cognitive performance and post-traumatic stress disorder: ImPACT, BrainCheckers and PCL-M test results. HBO₂ treatment correlated with stem cell mobilization as well as increased cognitive performance. Together these results support the hypothesis that stem cell mobilization may be required for cognitive improvement in this population. Copyright© Undersea and Hyperbaric Medical Society.

[Hyperbaric oxygen therapy and inert gases in cerebral ischemia and traumatic brain injury].

PubMed

Chhor, V; Canini, F; De Rudnicki, S; Dahmani, S; Gressens, P; Constantin, P

2013-12-01

Cerebral ischemia is a common thread of acute cerebral lesions, whether vascular or traumatic origin. Hyperbaric oxygen (HBO) improves tissue oxygenation and may prevent impairment of reversible lesions. In experimental models of cerebral ischemia or traumatic brain injury, HBO has neuroprotective effects which are related to various mechanisms such as modulation of oxidative stress, neuro-inflammation or cerebral and mitochondrial metabolism. However, results of clinical trials failed to prove any neuroprotective effects for cerebral ischemia and remained to be confirmed for traumatic brain injury despite preliminary encouraging results. The addition of inert gases to HBO sessions, especially argon or xenon which show neuroprotective experimental effects, may provide an additional improvement of cerebral lesions. Further multicentric studies with a strict methodology and a better targeted definition are required before drawing definitive conclusions about the efficiency of combined therapy with HBO and inert gases in acute cerebral lesions. Copyright © 2013 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier SAS. All rights reserved.

Hyperbaric oxygen therapy for systemic gas embolism after hydrogen peroxide ingestion.

PubMed

Byrne, Brendan; Sherwin, Robert; Courage, Cheryl; Baylor, Alfred; Dolcourt, Bram; Brudzewski, Jacek R; Mosteller, Jeffrey; Wilson, Robert F

2014-02-01

Hydrogen peroxide is a commonly available product and its ingestion has been demonstrated to produce in vivo gas bubbles, which can embolize to devastating effect. We report two cases of hydrogen peroxide ingestion with resultant gas embolization, one to the portal system and one cerebral embolus, which were successfully treated with hyperbaric oxygen therapy (HBO), and review the literature. Two individuals presented to our center after unintentional ingestion of concentrated hydrogen peroxide solutions. Symptoms were consistent with portal gas emboli (Patient A) and cerebral gas emboli (Patient B), which were demonstrated on imaging. They were successfully treated with HBO and recovered without event. As demonstrated by both our experience as well as the current literature, HBO has been used to successfully treat gas emboli associated with hydrogen peroxide ingestion. We recommend consideration of HBO in any cases of significant hydrogen peroxide ingestion with a clinical picture compatible with gas emboli. Copyright © 2014 Elsevier Inc. All rights reserved.

Normobaric and hyperbaric oxygen therapy for the treatment and prevention of migraine and cluster headache.

PubMed

Bennett, Michael H; French, Christopher; Schnabel, Alexander; Wasiak, Jason; Kranke, Peter; Weibel, Stephanie

2015-12-28

Migraine and cluster headaches are severe and disabling. Migraine affects up to 18% of women, while cluster headaches are much less common (0.2% of the population). A number of acute and prophylactic therapies are available. Hyperbaric oxygen therapy (HBOT) is the therapeutic administration of 100% oxygen at environmental pressures greater than one atmosphere, while normobaric oxygen therapy (NBOT) is oxygen administered at one atmosphere. This is an updated version of the original Cochrane review published in Issue 3, 2008 under the title 'Normobaric and hyperbaric oxygen for migraine and cluster headache'. To examine the efficacy and safety of normobaric oxygen therapy (NBOT) and hyperbaric oxygen therapy (HBOT) in the treatment and prevention of migraine and cluster headache. We updated searches of the following databases up to 15 June 2015: CENTRAL (the Cochrane Library), MEDLINE, EMBASE, and CINAHL. For the original review we searched the following databases up to May 2008: CENTRAL, MEDLINE, EMBASE, CINAHL, DORCTIHM, and reference lists from relevant articles. We handsearched relevant journals and contacted researchers to identify trials. Randomised controlled trials comparing HBOT or NBOT with one another, other active therapies, placebo (sham) interventions, or no treatment in participants with migraine or cluster headache. Three review authors independently extracted data and assessed the quality of the evidence using the GRADE approach. In this update, we included 11 trials with 209 participants. Five trials (103 participants) compared HBOT versus sham therapy for acute migraine, three trials compared NBOT to sham therapy or ergotamine tartrate for cluster headache (145 participants), two trials evaluated HBOT for cluster headache (29 participants), and one trial (56 participants) compared NBOT to sham for a mixed group of headache. The risk of bias varied considerably across these trials but in general trial quality was poor to moderate. One trial may not

Hyperbaric oxygen therapy (HBOT) in case of hemorrhagic cystitis after radiotherapy

PubMed Central

Klejnotowska, Alicja; Matuszewski, Marcin; Sicko, Zdzislaw; Markuszewski, Marcin; Krajka, Kazimierz

2012-01-01

Introduction We present the effect of hyperbaric oxygen therapy (HBOT) after radiotherapy for cancer in the pelvic cavity resulting in hematuria. Increasing the pressure of oxygen (PO2) in ischemic tissues favors the formation of new blood vessels and increases the secretion of collagen. Material and methods We evaluated 10 patients who were treated with HBOT from October 2006 to December 2010 due to persistent radiation damage to the lining of the bladder leading to recurrent hematuria. The study group was comprised of seven men and three women. In the case of cervical and endometrial cancers, 30 Gy of brachytherapy with 45-50 Gy of teleradiotherapy were used. In prostate cancer (PCa), we applied 50 Gy of teleradiotherapy with an additional dose of 20-24 Gy, and in the case of bladder cancer (BCa), 50 Gy of teleradiotherapy was applied with an additional dose of 16 Gy. HBOT consisted of 60 HBO2 treatments, in which patients were administered 100% oxygen at a pressure of 2.5 atm. Results The group effect of total or partial resolution was observed in six patients. In one case, treatment was discontinued due to an increase in hematuria and the consequent suspicion of bladder tumor recurrence. While in and additional three cases, the treatment did not produce the desired result. Conclusions Treatment of hemorrhagic cystitis is a difficult therapeutic challenge. One possible method is the implementation of HBOT. In very difficult cases, HBO2 treatment appears to be effective in giving more than half of patients a chance of getting better. PMID:24578962

The effect of hyperbaric oxygen treatment on aspiration pneumonia.

PubMed

Sahin, Sevtap Hekimoglu; Kanter, Mehmet; Ayvaz, Suleyman; Colak, Alkin; Aksu, Burhan; Guzel, Ahmet; Basaran, Umit Nusret; Erboga, Mustafa; Ozcan, Ali

2011-08-01

We have studied whether hyperbaric oxygen (HBO) prevents different pulmonary aspiration materials-induced lung injury in rats. The experiments were designed in 60 Sprague-Dawley rats, ranging in weight from 250 to 300 g, randomly allotted into one of six groups (n = 10): saline control, Biosorb Energy Plus (BIO), hydrochloric acid (HCl), saline + HBO treated, BIO + HBO treated, and HCl + HBO treated. Saline, BIO, HCl were injected into the lungs in a volume of 2 ml/kg. A total of seven HBO sessions were performed at 2,4 atm 100% oxygen for 90 min at 6-h intervals. Seven days later, rats were sacrificed, and both lungs in all groups were examined biochemically and histopathologically. Our findings show that HBO inhibits the inflammatory response reducing significantly (P < 0.05) peribronchial inflammatory cell infiltration, alveolar septal infiltration, alveolar edema, alveolar exudate, alveolar histiocytes, interstitial fibrosis, granuloma, and necrosis formation in different pulmonary aspiration models. Pulmonar aspiration significantly increased the tissue HP content, malondialdehyde (MDA) levels and decreased (P < 0.05) the antioxidant enzyme (SOD, GSH-Px) activities. HBO treatment significantly (P < 0.05) decreased the elevated tissue HP content, and MDA levels and prevented inhibition of SOD, and GSH-Px (P < 0.05) enzymes in the tissues. Furthermore, there is a significant reduction in the activity of inducible nitric oxide synthase, TUNEL and arise in the expression of surfactant protein D in lung tissue of different pulmonary aspiration models with HBO therapy. It was concluded that HBO treatment might be beneficial in lung injury, therefore, shows potential for clinical use.

Optimization of Intermittent Hyperbaric Oxygen Exposures by Duration of Oxygen Cycles

DTIC Science & Technology

2012-01-01

IL-1β, IL-6 as a marker of HBO2 toxicity; and (2) by gene expression of heat shock protein 70 (HSP70) as a potential protective factor against... potential use in clinical and military exposures and dives. For this reason, alternation of 30 and 60 min HBO2 cycles with 10 min hyperbaric air breaks was... potential fire/explosion hazards of exposure to several atmospheres of 100% O2. In addition, environmental factors, such as CO2 buildup

The use of hyperbaric oxygen therapy and LED therapy in diabetic foot

NASA Astrophysics Data System (ADS)

Marques, Cristiane R. S.; Martin, Airton A.; Lima, Carlos J.; Conrado, Luis A. L.; Silveira, Fabricio L.; Carvalho, Marcos V.

2004-07-01

Chronic foot ulcers are common ailments presented in diabetes, which offer severe complications and are often unresponsive to therapy. In this work it was evaluated the effects of adjunctive Hyperbaric Oxygen Therapy (HBO) treatment and LEDtherapy irradiation on ulcer healing (HBO) in addition to conventional treatment. In ulcers of diabetic foot these treatments lead to a reduction in the probability of amputation up to almost four times compared with patients not receiving such co-adjutant treatment. The LEDtherapy irradiation was given concurrently using an energy density of 4J/cm2 for 5 min. During the experiment nine patients with diabetic foot ulcers were submitted for HBO sessions with 2,5 ATM for two hours. The experiment demonstrated the effectiveness of HBO + LEDtherapy treatment by favoring the ulcer healing through an increased fibroblastic response, collagen synthesis and neo-vascularization of the ischaemia, as well as increases in the leukocytic bactericidal activity.

Effects of Exercise Training under Hyperbaric Oxygen on Oxidative Stress Markers and Endurance Performance in Young Soccer Players: A Pilot Study.

PubMed

Burgos, Carlos; Henríquez-Olguín, Carlos; Andrade, David Cristóbal; Ramírez-Campillo, Rodrigo; Araneda, Oscar F; White, Allan; Cerda-Kohler, Hugo

2016-01-01

The aim of the present study was to determine the effects of three weeks of hyperbaric oxygen (HBO 2 ) training on oxidative stress markers and endurance performance in young soccer players. Participants (18.6 ± 1.6 years) were randomized into hyperbaric-hyperoxic (HH) training ( n = 6) and normobaric normoxic (NN) training ( n = 6) groups. Immediately before and after the 5th, 10th, and 15th training sessions, plasma oxidative stress markers (lipid hydroperoxides and uric acid), plasma antioxidant capacity (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid [TROLOX]), arterial blood gases, acid-base balance, bases excess (BE), and blood lactate analyses were performed. Before and after intervention, maximal oxygen uptake (VO 2 max) and peak power output (PPO) were determined. Neither HH nor NN experienced significant changes on oxidative stress markers or antioxidant capacity during intervention. VO 2 max and PPO were improved (moderate effect size) after HH training. The results suggest that HBO 2 endurance training does not increase oxidative stress markers and improves endurance performance in young soccer players. Our findings warrant future investigation to corroborate that HBO 2 endurance training could be a potential training approach for highly competitive young soccer players.

Effects of topical nasal steroids and diclofenac on the nasal mucosa during hyperbaric oxygen therapy: a double-blind experimental study.

PubMed

Vuralkan, Erkan; Cobanoglu, Hatice Bengu; Arslan, Abdullah; Arslan, Selcuk; Mungan, Sevdegul; Tatar, Selcuk; Toklu, Akın Savas

2014-08-01

We aimed to evaluate nasal mucosal changes and efficiency of nasal steroids and diclofenac on nasal mucosa during hyperbaric oxygen (HBO) treatment. Forty adult Albino-Wistar rats were randomized into four groups. Group 1 (control group) (n = 10) not exposed to hyperbaric or enhanced oxygen concentrations; group 2 (HBO group) (n = 10) underwent only HBO treatment; group 3 (n = 10) received HBO and intranasal mometasone furoate (10 μl/day); group 4 (n = 10) treated with HBO and diclofenac sodium (10 mg/kg/day ip). Specimens of nasal mucosa were collected after sacrificing and dissection of animals. The specimens were processed for light microscopic evaluation, and then evaluated histopathologically for fibroblastic proliferation and inflammation. Regarding the scores of inflammation, the level of inflammation in the control group was significantly less severe than the other groups (p < 0.05). Evaluation of the fibrosis scores showed that the scores of both groups 2 and 4 were significantly increased (p < 0.05). There were no statistically significant differences between groups 2, 3, and 4 as for fibrosis and inflammation (p > 0.05). Chronic HBO treatment induced mild inflammation of the nasal mucosa. These effects cannot be prevented adequately by administration of nasal steroids and diclofenac.

Chamber personnel's use of Nitrox 50 during hyperbaric oxygen treatment: a quality study--research report.

PubMed

Hansen, Marco B; Jansen, Tejs; Sifakis, Michael B; Hyldegaard, Ole; Jansen, Erik C

2013-01-01

We aimed to evaluate the feasibility and safety of using Nitrox 50 as breathing gas during attendance in a multiplace hyperbaric chamber. Paper logs between Jan.-Dec. 2011 were reviewed to analyze nitrogen gas-loading, actual bottom time, total bottom time and surface interval time. With the use of the Norwegian Diving Tables nitrogen gas-loading was converted to Repetitive Group Letters. Symptoms of decompression sickness and health problems related to hyperbaric exposures were registered at weekly staff meetings. The chamber personnel breathed chamber air or Nitrox 50. 1,207 hyperbaric exposures were distributed to five chamber attendants and technicians, 14 doctors, and six nurses. Nitrox 50 was inhaled on 978 occasions (81.0%). Median nitrogen gas-loading after first pressurization complied with Repetitive Group Letter A (range A-E), second to C (range A-F), third to D (range A-F), fourth to E (range C-H), fifth to F (range C-H), and sixth to E (range B-G). No symptoms of decompression sickness were reported (95% CI 0.00-0.33%). Breathing Nitrox 50 during repetitive hyperbaric sessions seems to be feasible and safe while meeting high demands in number of treatment sessions and patient flow and with fewer people employed in the hyperbaric unit.

Immediate and delayed hyperbaric oxygen therapy as a neuroprotective treatment for traumatic brain injury in mice.

PubMed

Baratz-Goldstein, Renana; Toussia-Cohen, Shlomi; Elpaz, Aviya; Rubovitch, Vardit; Pick, Chaim G

2017-09-01

Traumatic brain injury is the most common cause of death or chronic disability among people under-35-years-old. There is no effective pharmacological treatment currently existing for TBI. Hyperbaric oxygen therapy (HBOT) is defined as the inhalation of pure oxygen in a hyperbaric chamber that is pressurized higher than 1atm. HBOT offers physiological and mechanical effects by inducing a state of increased pressure and hyperoxia. HBOT has been proposed as an effective treatment for moderate traumatic brain injury (mTBI), yet the exact therapeutic window and mechanism that underlies this effect is not completely understood. HBOT was administrated for 4 consecutive days, post a mouse closed head weight drop moderate TBI (mTBI) in 2 different time lines: immediate treatment - initiated 3h post-injury and delayed treatment - initiated 7days post-injury. Behavioral cognitive tests and biochemical changes were assessed. The results were similar for both the immediate and the delayed treatments. mTBI mice exhibited impairment in learning abilities, whereas mTBI mice treated with HBO displayed significant improvement compared with the mTBI group, performing similar to the sham groups. mTBI mice had a decline in myelin basic protein, an increase in neuronal loss (NeuN staining), and an increase in the number of reactive astrocytes (GFAP). The HBO treated mice in both groups did not exhibit these changes and remained similar to the sham group. The delayed HBOT has a potential to serve as a neuroprotective treatment for mTBI with a long therapeutic window. Further research is needed for fully understanding the cellular changes. Copyright © 2017 Elsevier Inc. All rights reserved.

Regional CBF in chronic stable TBI treated with hyperbaric oxygen.

PubMed

Barrett, K F; Masel, B; Patterson, J; Scheibel, R S; Corson, K P; Mader, J T

2004-01-01

To investigate whether Hyperbaric Oxygen Therapy (HBO2) could improve neurologic deficits and regional cerebral blood flow (rCBF) in chronic traumatic brain injuries (TBI), the authors employed a nonrandomized control pilot trial. Five subjects, at least three years post head injury, received HBO2. Five head injured controls (HIC) were matched for age, sex, and type of injury. Five healthy subjects served as normal controls. Sixty-eight normal volunteers comprised a reference data bank against which to compare SPECT brain scans. HBO2 subjects received 120 HBO2 in blocks of 80 and 40 treatments with an interval five-month break. Normal controls underwent a single SPECT brain scan, HBO2, and repeat SPECT battery. TBI subjects were evaluated by neurologic, neuropsychometric, exercise testing, and pre and post study MRIs, or CT scans if MRI was contraindicated. Statistical Parametric Mapping was applied to SPECT scans for rCBF analysis. There were no significant objective changes in neurologic, neuropsychometric, exercise testing, MRIs, or rCBF. In this small pilot study, HBO2 did not effect clinical or regional cerebral blood flow improvement in TBI subjects.

Portable Hyperbaric Chamber

NASA Technical Reports Server (NTRS)

Schneider, William C. (Inventor); Locke, James P. (Inventor); DeLaFuente, Horacio (Inventor)

2001-01-01

A portable, collapsible hyperbaric chamber was developed. A toroidal inflatable skeleton provides initial structural support for the chamber, allowing the attendant and/or patient to enter the chamber. Oval hatches mate against bulkhead rings, and the hyperbaric chamber is pressurized. The hatches seal against an o-ring, and the internal pressure of the chamber provides the required pressure against the hatch to maintain an airtight seal. In the preferred embodiment, the hyperbaric chamber has an airlock to allow the attendant to enter and exit the patient chamber during treatment. Visual communication is provided through portholes in the patient and/or airlock chamber. Life monitoring and support systems are in communication with the interior of the hyperbaric chamber and/or airlock chamber through conduits and/or sealed feed-through connectors into the hyperbaric chamber.

Effects of hyperbaric exposure on eyes with intraocular gas bubbles.

PubMed

Jackman, S V; Thompson, J T

1995-01-01

Air travel is known to be potentially hazardous for patients with intraocular gas bubbles, and the external pressure changes associated with hyperbaric oxygen therapy and scuba diving could be similarly dangerous. Rabbits with a perfluoropropane/air gas mixture filling approximately 60% of the vitreous cavity of the right eye were exposed to 3 different hyperbaric pressure profiles to an equivalent depth of 33 feet. The first group were a control group and were not exposed to hyperbaric pressures. The second group remained at an equivalent depth of 33 feet for 30 minutes, and the third group remained at 33 feet for 1 minute. Both groups ascended to normal atmospheric pressure at a rate of 1 foot per minute. The fourth group remained at 33 feet for 1 minute and then ascended at a rate of 0.2 feet per minute. In all eyes with an intraocular gas bubble, intraocular pressure dropped to zero when the atmospheric pressure was increased, and rose to more than 50 mmHg when the atmospheric pressure was returned to normal. Pressures in excess of 50 mmHg were sustained for 10 minutes or longer in each rabbit exposed to one of the hyperbaric profiles. No significant intraocular pressure changes were observed in eyes without an intraocular gas bubble or eyes not exposed to hyperbaric pressure. Marked elevation in intraocular pressure occurs as a result of hyperbaric exposure in eyes with an intraocular gas bubble. Hyperbaric exposure is therefore not advisable for patients with intraocular gas bubbles.

Randomized, Sham-Controlled, Feasibility Trial of Hyperbaric Oxygen for Service Members With Postconcussion Syndrome: Cognitive and Psychomotor Outcomes 1 Week Postintervention.

PubMed

Walker, William C; Franke, Laura Manning; Cifu, David X; Hart, Brett B

2014-06-01

Background Mild traumatic brain injury (mTBI) and residual postconcussion syndrome (PCS) are common among combatants of the recent military conflicts in Iraq and Afghanistan. Hyperbaric oxygen (HBO2) is a proposed treatment but has not been rigorously studied for this condition. Objectives In a secondary analysis, examine for possible effects on psychomotor (balance and fine motor) and cognitive performance 1 week after an HBO2 intervention in service members with PCS after mTBI. Methods A randomized, double-blind, sham control, feasibility trial comparing pretreatment and posttreatment was conducted in 60 male active-duty marines with combat-related mTBI and PCS persisting for 3 to 36 months. Participants were randomized to 1 of 3 preassigned oxygen fractions (10.5%, 75%, or 100%) at 2.0 atmospheres absolute (ATA), resulting in respective groups with an oxygen exposure equivalent to (1) breathing surface air (Sham Air), (2) 100% oxygen at 1.5 ATA (1.5 ATAO2), and (3) 100% oxygen at 2.0 ATA (2.0 ATAO2). Over a 10-week period, participants received 40 hyperbaric chamber sessions of 60 minutes each. Outcome measures, including computerized posturography (balance), grooved pegboard (fine motor speed/dexterity), and multiple neuropsychological tests of cognitive performance, were collected preintervention and 1-week postintervention. Results Despite the multiple sensitive cognitive and psychomotor measures analyzed at an unadjusted 5% significance level, this study demonstrated no immediate postintervention beneficial effect of exposure to either 1.5 ATAO2 or 2.0 ATAO2 compared with the Sham Air intervention. Conclusions These results do not support the use of HBO2 to treat cognitive, balance, or fine motor deficits associated with mTBI and PCS. © The Author(s) 2013.

Effects of Exercise Training under Hyperbaric Oxygen on Oxidative Stress Markers and Endurance Performance in Young Soccer Players: A Pilot Study

PubMed Central

Henríquez-Olguín, Carlos; Andrade, David Cristóbal; Ramírez-Campillo, Rodrigo; White, Allan; Cerda-Kohler, Hugo

2016-01-01

The aim of the present study was to determine the effects of three weeks of hyperbaric oxygen (HBO2) training on oxidative stress markers and endurance performance in young soccer players. Participants (18.6 ± 1.6 years) were randomized into hyperbaric-hyperoxic (HH) training (n = 6) and normobaric normoxic (NN) training (n = 6) groups. Immediately before and after the 5th, 10th, and 15th training sessions, plasma oxidative stress markers (lipid hydroperoxides and uric acid), plasma antioxidant capacity (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid [TROLOX]), arterial blood gases, acid-base balance, bases excess (BE), and blood lactate analyses were performed. Before and after intervention, maximal oxygen uptake (VO2max) and peak power output (PPO) were determined. Neither HH nor NN experienced significant changes on oxidative stress markers or antioxidant capacity during intervention. VO2max and PPO were improved (moderate effect size) after HH training. The results suggest that HBO2 endurance training does not increase oxidative stress markers and improves endurance performance in young soccer players. Our findings warrant future investigation to corroborate that HBO2 endurance training could be a potential training approach for highly competitive young soccer players. PMID:28083148

Hyberbaric oxygen as sole treatment for severe radiation - induced haemorrhagic cystitis

PubMed Central

Dellis, Athanasios; Papatsoris, Athanasios; Kalentzos, Vasileios; Deliveliotis, Charalambos; Skolarikos, Andreas

2017-01-01

ABSTRACT Purpose To examine the safety and efficacy of hyperbaric oxygen as the primary and sole treatment for severe radiation-induced haemorrhagic cystitis. Materials and methods Hyperbaric oxygen was prospectively applied as primary treatment in 38 patients with severe radiation cystitis. Our primary endpoint was the incidence of complete and partial response to treatment, while the secondary endpoints included the duration of response, the correlation of treatment success-rate to the interval between the onset of haematuria and initiation of therapy, blood transfusion need and total radiation dose, the number of sessions to success, the avoidance of surgery and the overall survival. Results All patients completed therapy without complications with a mean follow-up of 29.33 months. Median number of sessions needed was 33. Complete and partial response rate was 86.8% and 13.2%, respectively. All 33 patients with complete response received therapy within 6 months of the haematuria onset. One patient needed cystectomy, while 33 patients were alive at the end of follow-up. Conclusions Our study suggests the early primary use of hyperbaric oxygen for radiation-induced severe cystitis as an effective and safe treatment option. PMID:28338304

The effect of acute exposure to hyperbaric oxygen on respiratory system mechanics in the rat.

PubMed

Rubini, Alessandro; Porzionato, Andrea; Zara, Susi; Cataldi, Amelia; Garetto, Giacomo; Bosco, Gerardo

2013-10-01

This study was designed to investigate the possible effects of acute hyperbaric hyperoxia on respiratory mechanics of anaesthetised, positive-pressure ventilated rats. We measured respiratory mechanics by the end-inflation occlusion method in nine rats previously acutely exposed to hyperbaric hyperoxia in a standard fashion. The method allows the measurements of respiratory system elastance and of both the "ohmic" and of the viscoelastic components of airway resistance, which respectively depend on the newtonian pressure dissipation due to the ohmic airway resistance to air flow, and on the viscoelastic pressure dissipation caused by respiratory system tissues stress-relaxation. The activities of inducible and endothelial NO-synthase in the lung's tissues (iNOS and eNOS respectively) also were investigated. Data were compared with those obtained in control animals. We found that the exposure to hyperbaric hyperoxia increased respiratory system elastance and both the "ohmic" and viscoelastic components of inspiratory resistances. These changes were accompanied by increased iNOS but not eNOS activities. Hyperbaric hyperoxia was shown to acutely induce detrimental effects on respiratory mechanics. A possible causative role was suggested for increased nitrogen reactive species production because of increased iNOS activity.

Hyperbaric oxygen treatment for carbon monoxide intoxication acquired in the sealed room during the Persian Gulf war.

PubMed

Adir, Y; Bitterman, H; Kol, S; Melamed, Y

1991-01-01

During the recent Persian Gulf war, the civilian population in Israel was frequently instructed to stay in sealed rooms in preparation for a possible chemical missile attack. The war broke out in mid-winter, and in many instances it was necessary to heat the rooms. The use of open fires or malfunctioning heating appliances inside sealed rooms could create ideal conditions for carbon monoxide (CO) poisoning. Six patients with CO intoxication resulting from confinement inside sealed rooms were referred for hyperbaric oxygen (HBO) treatment. Indications for HBO therapy were loss of consciousness and metabolic acidosis. The treatment protocol consisted of 90-min exposure to 100% oxygen at 2.5 atmospheres absolute (ATA), with repeated exposures when required. All patients made a full recovery. The risk of CO poisoning should be taken into consideration and should determine the selection of heating devices for future use in similar circumstances.

Report on Hyperbaric Oxygen Therapy: An Overlooked Therapeutic Option in Stroke Recovery and a Potential Source of Health Sector Revenue and Health Tourism.

PubMed

Lowe, S; Le Mercier du Quesnay, D R; Gayle, Pmh; Henry-Pinnock, F; Wedderburn-Buddo, T

2015-06-30

This is a special case report on Jamaica's first use of hyperbaric oxygen therapy (HBOT) in stroke recovery, presented at the 56 th Annual Conference of the Association of Surgeons in Jamaica, Kingston, Jamaica. The literature and story behind the trial ‒ covering case history, diagnosis and discussion of outcome ‒ technical issues, costing, insurance and possibilities for income earning and health tourism are explored.

Effects of hyperbaric oxygen and nerve growth factor on the long-term neural behavior of neonatal rats with hypoxic ischemic brain damage.

PubMed

Wei, Lixia; Ren, Qing; Zhang, Yongjun; Wang, Jiwen

2017-04-01

To evaluate the effects of HBO (Hyperbaric oxygen) and NGF (Nerve growth factor) on the long-term neural behavior of neonatal rats with HIBD (Neonatal hypoxic ischemic brain damage). The HIBD model was produced by ligating the right common carotid artery of 7 days old SD (Sprague-Dawley) rats followed by 8% O2 + 92% N2 for 2h. Totally 40 rats were randomly divided into 5 groups including sham-operated group, HIBD control group, HBO treated group, NGF treated group and NGF + HBO treated group. The learning and memory ability of these rats was evaluated by Morris water maze at 30 days after birth, and sensory motor function was assessed by experiments of foot error and limb placement at 42 days after birth. The escape latency of HBO treated group, NGF treated group and NGF + HBO treated group was shorter than that of HIBD control group (p<0.01) and longer than that of sham-operated group. The piercing indexes of 3 treated groups were higher than that of HIBD control group (p<0.01). Hyperbaric oxygen and nerve growth factor treatments may improve learning and memory ability and sensory motor function in neonatal rats after hypoxic ischemic brain damage.

[Evaluation of different oxygen therapies on therapeutic effects in rats with acute carbon dioxide poisoning].

PubMed

Niu, Ying-mei; Hao, Feng-tong; Xue, Chang-jiang; Xia, Yu-jing; Zhou, Shuo; Lu, Qing-sheng; Liu, Jian-zhong; Zhang, Peng

2011-03-01

significant difference of the arterial pH, PO2 and PCO2 among oxygen treatment groups (P > 0.05). There was large area of bleeding of lungs in rats with carbon dioxide poisoning, the bleeding of lungs in rats with high concentration of atmospheric oxygen treatment and low concentration of atmospheric oxygen treatment was better than the rats with carbon dioxide poisoning, there was no abnormal appearance of lungs in rats with hyperbaric oxygen treatment. The light microscope observation showed that there were diffuse bleeding and exudation of lungs in rats with carbon dioxide poisoning, the bleeding and exudation of lungs in rats with high concentration of atmospheric oxygen treatment and low concentration of atmospheric oxygen treatment were better than the rats with carbon dioxide poisoning, there were only minor bleeding and exudation of lungs in rats with hyperbaric oxygen treatment. There was no difference of brain in anatomy and microscopy among all groups, there were no significant bleeding, edema, cell degeneration and necrosis. Lung pathology in acute carbon dioxide poisoning rats with hyperbaric oxygen treatment is better than the rats with high concentration of atmospheric oxygen treatment and low concentration of atmospheric oxygen treatment, there is no significant difference of effect between high concentration of atmospheric oxygen treatment group and low concentration of atmospheric oxygen treatment group, however, the results of blood gas analysis and lung pathology than the exposure group improved, so qualified medical unit for hyperbaric oxygen therapy as soon as possible, hyperbaric oxygen treatment facilities in the absence of circumstances, the emergency treatment of early oxygen is also a good measure.

Relationship of oxygen dose to angiogenesis induction in irradiated tissue

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marx, R.E.; Ehler, W.J.; Tayapongsak, P.

1990-11-01

This study was accomplished in an irradiated rabbit model to assess the angiogenic properties of normobaric oxygen and hyperbaric oxygen as compared with air-breathing controls. Results indicated that normobaric oxygen had no angiogenic properties above normal revascularization of irradiated tissue than did air-breathing controls (p = 0.89). Hyperbaric oxygen demonstrated an eight- to ninefold increased vascular density over both normobaric oxygen and air-breathing controls (p = 0.001). Irradiated tissue develops a hypovascular-hypocellular-hypoxic tissue that does not revascularize spontaneously. Results failed to demonstrate an angiogenic effect of normobaric oxygen. It is suggested that oxygen in this sense is a drug requiringmore » hyperbaric pressures to generate therapeutic effects on chronically hypovascular irradiated tissue.« less

The Effects of Hyperbaric Oxygen Therapy on Post-Training Recovery in Jiu-Jitsu Athletes.

PubMed

Branco, Braulio Henrique Magnani; Fukuda, David Hideyoshi; Andreato, Leonardo Vidal; Santos, Jonatas Ferreira da Silva; Esteves, João Victor Del Conti; Franchini, Emerson

2016-01-01

The present study aimed to evaluate the effects of using hyperbaric oxygen therapy during post-training recovery in jiu-jitsu athletes. Eleven experienced Brazilian jiu-jitsu athletes were investigated during and following two training sessions of 1h30min. Using a cross-over design, the athletes were randomly assigned to passive recovery for 2 hours or to hyperbaric oxygen therapy (OHB) for the same duration. After a 7-day period, the interventions were reversed. Before, immediately after, post 2 hours and post 24 hours, blood samples were collected to examine hormone concentrations (cortisol and total testosterone) and cellular damage markers [creatine kinase (CK), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH)]. Moreover, the rating of perceived exertion (RPE) and recovery (RPR) scales were applied. Final lactate [La] values (control: 11.9 ± 1.4 mmol/L, OHB: 10.2 ± 1.4 mmol/L) and RPE [control: 14 (13-17 a.u.), OHB: 18 (17-20 a.u.)] were not significantly different following the training sessions. Furthermore, there was no difference between any time points for blood lactate and RPE in the two experimental conditions (P>0.05). There was no effect of experimental conditions on cortisol (F1,20 = 0.1, P = 0.793, η2 = 0.00, small), total testosterone (F1,20 = 0.03, P = 0.877, η2 = 0.00, small), CK (F1,20 = 0.1, P = 0.759, η2 = 0.01, small), AST (F1,20 = 0.1, P = 0.761, η2 = 0.01, small), ALT (F1,20 = 0.0, P = 0.845, η2 = 0.00, small) or LDH (F1,20 = 0.7, P = 0.413, η2 = 0.03, small). However, there was a difference between the two experimental conditions in RPR with higher values at post 2 h and 24 h in OHB when compared to the control condition (P<0.05). Thus, it can be concluded that OHB exerts no influence on the recovery of hormonal status or cellular damage markers. Nonetheless, greater perceived recovery, potentially due to the placebo effect, was evident following the OHB condition.

The Effects of Hyperbaric Oxygen Therapy on Post-Training Recovery in Jiu-Jitsu Athletes

PubMed Central

Santos, Jonatas Ferreira da Silva; Esteves, João Victor Del Conti

2016-01-01

Objectives The present study aimed to evaluate the effects of using hyperbaric oxygen therapy during post-training recovery in jiu-jitsu athletes. Methods Eleven experienced Brazilian jiu-jitsu athletes were investigated during and following two training sessions of 1h30min. Using a cross-over design, the athletes were randomly assigned to passive recovery for 2 hours or to hyperbaric oxygen therapy (OHB) for the same duration. After a 7-day period, the interventions were reversed. Before, immediately after, post 2 hours and post 24 hours, blood samples were collected to examine hormone concentrations (cortisol and total testosterone) and cellular damage markers [creatine kinase (CK), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH)]. Moreover, the rating of perceived exertion (RPE) and recovery (RPR) scales were applied. Results Final lactate [La] values (control: 11.9 ± 1.4 mmol/L, OHB: 10.2 ± 1.4 mmol/L) and RPE [control: 14 (13–17 a.u.), OHB: 18 (17–20 a.u.)] were not significantly different following the training sessions. Furthermore, there was no difference between any time points for blood lactate and RPE in the two experimental conditions (P>0.05). There was no effect of experimental conditions on cortisol (F1,20 = 0.1, P = 0.793, η2 = 0.00, small), total testosterone (F1,20 = 0.03, P = 0.877, η2 = 0.00, small), CK (F1,20 = 0.1, P = 0.759, η2 = 0.01, small), AST (F1,20 = 0.1, P = 0.761, η2 = 0.01, small), ALT (F1,20 = 0.0, P = 0.845, η2 = 0.00, small) or LDH (F1,20 = 0.7, P = 0.413, η2 = 0.03, small). However, there was a difference between the two experimental conditions in RPR with higher values at post 2 h and 24 h in OHB when compared to the control condition (P<0.05). Conclusions Thus, it can be concluded that OHB exerts no influence on the recovery of hormonal status or cellular damage markers. Nonetheless, greater perceived recovery, potentially due to the placebo effect, was evident

A prospective trial of hyperbaric oxygen for chronic sequelae after brain injury (HYBOBI).

PubMed

Churchill, Susan; Weaver, Lindell K; Deru, Kayla; Russo, Antonietta A; Handrahan, Diana; Orrison, William W; Foley, John F; Elwell, Heather A

2013-01-01

Some practitioners advocate hyperbaric oxygen (HBO2) for sequelae following brain injury. This study assessed recruitment, tolerance and safety in preparation for a randomized clinical trial. Prospective, open-label feasibility study. Hyperbaric medicine department of a tertiary academic hospital. Participatory adult outpatients with problems from stroke (n=22), anoxia (13) or trauma (28) that occurred at least 12 months before enrollment, without contraindications to HBO2. Sixty-three participants enrolled in the study (21 females,42 males). Age was 45 +/- 16 years (18-76) and time from injury was 6.9 +/- 7.1 years (1.0-29.3). Fifty-three completed the study intervention, and 55 completed the assessment battery. PARTICIPANTS underwent 60 daily HBO2 sessions (1.5 atm abs, 100% oxygen, 60 minutes). Assessments were conducted at baseline, after the HBO2 course, and six months later. The prime outcome was feasibility. To estimate the immediate and long-term effects of HBO2, we assessed neuropsychological measures, questionnaires, neurologic exam and physical functioning measures. Some participants also had pre- and post-HBO2 speech evaluation (n=27) and neuroimaging (n=17). The study met our a priori definition for feasibility for recruitment, but 44% required additional time to complete the 60 sessions (up to 105 days). HBO2-related adverse events were rare and not serious. Although many participants reported improvement in symptoms (51% memory, 51% attention/concentration, 48% balance/coordination, 45% endurance, 20% sleep) post-HBO2, and 93% reported that they would participate in the study again, no standardized testing showed clinically important improvement. In the small subset of those undergoing neuroimaging, apparent improvement was observed in auditory functional MRI (8/13), MR spectroscopy (9/17) and brain perfusionby CT angiography (5/9). Conducting an HBO2 clinical trial in this population was feasible. Although many participants reported improvement, the

99mTc-ECD brain perfusion SPECT imaging for the assessment of brain perfusion in cerebral palsy (CP) patients with evaluation of the effect of hyperbaric oxygen therapy.

PubMed

Asl, Mina Taghizadeh; Yousefi, Farzaneh; Nemati, Reza; Assadi, Majid

2015-01-01

The present study was carried out to evaluate cerebral perfusion in different types of cerebral palsy (CP) patients. For those patients who underwent hyperbaric oxygen therapy, brain perfusion before and after the therapy was compared. A total of 11 CP patients were enrolled in this study, of which 4 patients underwent oxygen therapy. Before oxygen therapy and at the end of 40 sessions of oxygen treatment, 99mTc-ECD brain perfusion single photon emission computed tomography (SPECT) was performed , and the results were compared. A total of 11 CP patients, 7 females and 4 males with an age range of 5-27 years participated in the study. In brain SPECT studies, all the patients showed perfusion impairments. The region most significantly involved was the frontal lobe (54.54%), followed by the temporal lobe (27.27%), the occipital lobe (18.18%), the visual cortex (18.18%), the basal ganglia (9.09%), the parietal lobe (9.09%), and the cerebellum (9.09%). Frontal-lobe hypoperfusion was seen in all types of cerebral palsy. Two out of 4 patients (2 males and 2 females) who underwent oxygen therapy revealed certain degree of brain perfusion improvement. This study demonstrated decreased cerebral perfusion in different types of CP patients. The study also showed that hyperbaric oxygen therapy improved cerebral perfusion in a few CP patients. However, it could keep the physiological discussion open and strenghten a link with other areas of neurology in which this approach may have some value.

Hyperbaric oxygen treatment in autism spectrum disorders

PubMed Central

2012-01-01

Traditionally, hyperbaric oxygen treatment (HBOT) is indicated in several clinical disorders include decompression sickness, healing of problem wounds and arterial gas embolism. However, some investigators have used HBOT to treat individuals with autism spectrum disorders (ASD). A number of individuals with ASD possess certain physiological abnormalities that HBOT might ameliorate, including cerebral hypoperfusion, inflammation, mitochondrial dysfunction and oxidative stress. Studies of children with ASD have found positive changes in physiology and/or behavior from HBOT. For example, several studies have reported that HBOT improved cerebral perfusion, decreased markers of inflammation and did not worsen oxidative stress markers in children with ASD. Most studies of HBOT in children with ASD examined changes in behaviors and reported improvements in several behavioral domains although many of these studies were not controlled. Although the two trials employing a control group reported conflicting results, a recent systematic review noted several important distinctions between these trials. In the reviewed studies, HBOT had minimal adverse effects and was well tolerated. Studies which used a higher frequency of HBOT sessions (e.g., 10 sessions per week as opposed to 5 sessions per week) generally reported more significant improvements. Many of the studies had limitations which may have contributed to inconsistent findings across studies, including the use of many different standardized and non-standardized instruments, making it difficult to directly compare the results of studies or to know if there are specific areas of behavior in which HBOT is most effective. The variability in results between studies could also have been due to certain subgroups of children with ASD responding differently to HBOT. Most of the reviewed studies relied on changes in behavioral measurements, which may lag behind physiological changes. Additional studies enrolling children with ASD

Histologic morphometry confirms a prophylactic effect for hyperbaric oxygen in the prevention of delayed radiation enteropathy.

PubMed

Feldmeier, J J; Davolt, D A; Court, W S; Onoda, J M; Alecu, R

1998-01-01

In a previous publication (Feldmeier et al., Radiother Oncol 1995; 35:138-144) we reported our success in preventing delayed radiation enteropathy in a murine model by the application of hyperbaric oxygen (HBO2). In this study we introduce a histologic morphometric technique for assessing fibrosis in the submucosa of these same animal specimens and relate this assay to the previous results. The histologic morphometry, like the previous gross morphometry and compliance assays, demonstrates a significant protective effect for HBO2. The present assay is related to the previous assays in a statistically significant fashion. The predictive value for the histologic morphometric assay demonstrates a sensitivity of 75% and a specificity of 62.5%. The applicability of this assay to other organ systems and its potential superiority to the compliance assay are discussed.

[Effects of hyperbaric oxygenation on oxidative phosphorylation in post-nephrotomy tissues sutured with different surgical threads (an experimental study)].

PubMed

Kostenko, V A

1998-01-01

The activity of mitochondrial respiration and oxidative phosphorylation (OP) was studied in white rats subjected to nephrotomy. The suture was made with absorbable surgical threads such as catgut plain, biofil (from dura mater spinalis of the cattle), dexon II (polyglycolic acid). The use of catgut plain inhibits biosynthetic processes 7 and 14 days after operation. Hyperbaric oxygenation enhances oxidative phosphorylation in postoperative renal tissue sutured with different biological and synthetic absorbable surgical threads (catgut, biofil, dexon II) and prevents sharp depression of the above processes in the course of catgut biodegradation. This fact is of great importance for reduction of normal functional and metabolic activity of the operated kidney.

Successful hyperbaric oxygen therapy for refractory BK virus-associated hemorrhagic cystitis after cord blood transplantation.

PubMed

Hosokawa, K; Yamazaki, H; Nakamura, T; Yoroidaka, T; Imi, T; Shima, Y; Ohata, K; Takamatsu, H; Kotani, T; Kondo, Y; Takami, A; Nakao, S

2014-10-01

BK virus-associated hemorrhagic cystitis (BKV-HC) is a common and major cause of morbidity in recipients of allogeneic hematopoietic stem cell transplantation. A 32-year-old woman developed severe BKV-HC on day 24 after cord blood transplantation (CBT). Despite supportive therapies - such as hyperhydration, forced diuresis, and urinary catheterization - macroscopic hematuria and bladder irritation persisted for over a month. Hyperbaric oxygen (HBO) therapy at 2.1 atmospheres for 90 min per day was started on day 64 after CBT. Macroscopic hematuria resolved within a week, and microscopic hematuria was no longer detectable within 2 weeks. Hematuria did not recur after 11 sessions of HBO therapy, and no significant side effects were observed during or after treatment. HBO therapy could thus be useful in controlling refractory BKV-HC after CBT. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Early CT findings of Fournier's gangrene in a healthy male.

PubMed

Sherman, J; Solliday, M; Paraiso, E; Becker, J; Mydlo, J H

1998-01-01

Early clinical identification of Fournier's gangrene is imperative to avoid delay in the aggressive surgical debridement, antibiotic therapy, and sometimes hyperbaric oxygen treatments. We report on the early computed tomography findings of a non-gas-forming Fournier's gangrene in a healthy male to aid urologists, surgeons, and radiologists in the recognition of this rapidly progressive and often fatal infection.

Hyperbaric oxygen preconditioning protects against traumatic brain injury at high altitude.

PubMed

Hu, S L; Hu, R; Li, F; Liu, Z; Xia, Y Z; Cui, G Y; Feng, H

2008-01-01

Recent studies have shown that preconditioning with hyperbaric oxygen (HBO) can reduce ischemic and hemorrhagic brain injury. We investigated effects of HBO preconditioning on traumatic brain injury (TBI) at high altitude and examined the role of matrix metalloproteinase-9 (MMP-9) in such protection. Rats were randomly divided into 3 groups: HBO preconditioning group (HBOP; n = 13), high-altitude group (HA; n = 13), and high-altitude sham operation group (HASO; n = 13). All groups were subjected to head trauma by weight-drop device, except for HASO group. HBOP rats received 5 sessions of HBO preconditioning (2.5 ATA, 100% oxygen, 1 h daily) and then were kept in hypobaric chamber at 0.6 ATA (to simulate pressure at 4000m altitude) for 3 days before operation. HA rats received control pretreatment (1 ATA, room air, 1 h daily), then followed the same procedures as HBOP group. HASO rats were subjected to skull opening only without brain injury. Twenty-four hours after TBI, 7 rats from each group were examined for neurological function and brain water content; 6 rats from each group were killed for analysis by H&E staining and immunohistochemistry. Neurological outcome in HBOP group (0.71 +/- 0.49) was better than HA group (1.57 +/- 0.53; p < 0.05). Preconditioning with HBO significantly reduced percentage of brain water content (86.24 +/- 0.52 vs. 84.60 +/- 0.37; p < 0.01). Brain morphology and structure seen by light microscopy was diminished in HA group, while fewer pathological injuries occurred in HBOP group. Compared to HA group, pretreatment with HBO significantly reduced the number of MMP-9-positive cells (92.25 +/- 8.85 vs. 74.42 +/- 6.27; p < 0.01). HBO preconditioning attenuates TBI in rats at high altitude. Decline in MMP-9 expression may contribute to HBO preconditioning-induced protection of brain tissue against TBI.

Hyperbaric Oxygen Reduces Aspergillus fumigatus Proliferation In Vitro and Influences In Vivo Disease Outcomes.

PubMed

Dhingra, Sourabh; Buckey, Jay C; Cramer, Robert A

2018-03-01

Recent estimates suggest that more than 3 million people have chronic or invasive fungal infections, causing more than 600,000 deaths every year. Aspergillus fumigatus causes invasive pulmonary aspergillosis (IPA) in patients with compromised immune systems and is a primary contributor to increases in human fungal infections. Thus, the development of new clinical modalities as stand-alone or adjunctive therapy for improving IPA patient outcomes is critically needed. Here we tested the in vitro and in vivo impacts of hyperbaric oxygen (HBO) (100% oxygen, >1 atmosphere absolute [ATA]) on A. fumigatus proliferation and murine IPA outcomes. Our findings indicate that HBO reduces established fungal biofilm proliferation in vitro by over 50%. The effect of HBO under the treatment conditions was transient and fungistatic, with A. fumigatus metabolic activity rebounding within 6 h of HBO treatment being removed. In vivo , daily HBO provides a dose-dependent but modest improvement in murine IPA disease outcomes as measured by survival analysis. Intriguingly, no synergy was observed between subtherapeutic voriconazole or amphotericin B and HBO in vitro or in vivo with daily HBO dosing, though the loss of fungal superoxide dismutase genes enhanced HBO antifungal activity. Further studies are needed to optimize the HBO treatment regimen and better understand the effects of HBO on both the host and the pathogen during a pulmonary invasive fungal infection. Copyright © 2018 American Society for Microbiology.

Effects of Atmospheric Contaminants under Hyperbaric Conditions with Particular Reference to Vision

DTIC Science & Technology

1986-08-13

effects on consciousness. Proceedings of international symposium on submarine and space medicine. New York: MacMillan, pp. 3-18. Phil , R.O., Parkes...evaluation of pharmacological agents in hyperbaric air and helium-oxygen. In C.W. Shilling and W.M. Beckett , Underwater Physiology

Delayed hyperbaric oxygen therapy for air emboli after open heart surgery: case report and review of a success story.

PubMed

Niyibizi, Eva; Kembi, Guillaume Elyes; Lae, Claude; Pignel, Rodrigue; Sologashvili, Tornike

2016-12-05

The current case describes a rare diagnosis of iatrogenic air emboli after elective cardiopulmonary bypass that was successfully treated with delayed hyperbaric oxygen therapy, with good clinical evolution in spite of rare complications. A 35 years old male was admitted to the intensive care unit (ICU) for post-operative management after being placed on cardiopulmonary bypass (CPB) for an elective ventricular septal defect closure and aortic valvuloplasty. The patient initially presented with pathologically late awakening and was extubated 17 h after admission. Neurologic clinical status after extubation showed global aphasia, mental slowness and spatio-temporal disorientation. The injected cerebral CT scan was normal; the EEG was inconclusive (it showed metabolic encephalopathy without epileptic activity); and the cerebral MRI done 48 h after surgery showed multiple small subcortical acute ischemic lesions, mainly on the left fronto- parieto- temporo-occipital lobes. He was taken for hyperbaric oxygen therapy (HOT) over 54 h after cardiac surgery. The first session ended abruptly after 20 min when the patient suffered a generalised tonico-clonic seizure, necessitating a moderately rapid decompression, airway management, and antiepileptic treatment. In total, the patient received 7 HOT sessions over 6 days. He demonstrated full neurological recovery at 4 weeks and GOS (Glasgow Outcome Scale) of 5 out of 5 even after a long delay in initial management. Convulsions are a rare complication of HOT either due to reperfusion syndrome or hyperoxic toxicity and can be managed. Prior imaging by MRI or tympanic paracentesis (myringotomy) should not add further delay of treatment. HOT should be initiated upon late awakening and/or neurologic symptoms after CPB heart surgery, after exclusion of formal counter-indications, even if the delay exceeds 48 h.

Hyperbaric Oxygen Therapy in the Treatment of Chronic Mild-Moderate Blast-Induced Traumatic Brain Injury Post-Concussion Syndrome (PCS) and Post Traumatic Stress Disorder (PTSD)

DTIC Science & Technology

2017-10-01

a randomized sham- controlled double-blind design with the sham- control group receiving slightly pressurized air at the beginning and end of each... controlled ( non -treatment, non -sham) single-arm crossover single-blind study. The scope of the project is to recruit, enroll, test, treat, re-test and...the P.I. conducted a non - controlled pilot trial of hyperbaric oxygen therapy (HBOT 1.5 atmospheres absolute/60 minutes, twice/day, 40 treatments

Investigation of endocrine and immunological response in fat tissue to hyperbaric oxygen administration in rats.

PubMed

Şen, H; Erbağ, G; Ovali, M A; Öztopuz, R Ö; Uzun, M

2016-04-30

Though HBO treatment is becoming more common, the mechanism of action is not fully known. The positive effects of HBO administration on the inflammatory response is thought to be a possible basic mechanism. As a result, we aimed to research whether endocrine and immunological response of fat tissue changes in rats given HBO treatment model. This research was carried out on Wistar albino rats, they were treated with hyperbaric oxygen therapy. Their fatty tissue were taken from the abdomen, gene expression of the cytokines and adipokines were analyzed with Real time PCR method. When the gene expression of hormones and cytokines by fat tissue was examined, the leptin, visfatin, TNF-α, IL-1β and IL-10 levels in the HBO treatment group were statistically significantly increased compared to the control group (p=0.0313, p=0.0156, p=0.0156, p=0.0156, p=0.0313). In conclusion, in our study we identified that HBO administration affected the endochrinological functions of fat tissue.

Inhibition of hypoxia-associated response and kynurenine production in response to hyperbaric oxygen as mechanisms involved in protection against experimental cerebral malaria.

PubMed

Bastos, Marcele F; Kayano, Ana Carolina A V; Silva-Filho, João Luiz; Dos-Santos, João Conrado K; Judice, Carla; Blanco, Yara C; Shryock, Nathaniel; Sercundes, Michelle K; Ortolan, Luana S; Francelin, Carolina; Leite, Juliana A; Oliveira, Rafaella; Elias, Rosa M; Câmara, Niels O S; Lopes, Stefanie C P; Albrecht, Letusa; Farias, Alessandro S; Vicente, Cristina P; Werneck, Claudio C; Giorgio, Selma; Verinaud, Liana; Epiphanio, Sabrina; Marinho, Claudio R F; Lalwani, Pritesh; Amino, Rogerio; Aliberti, Julio; Costa, Fabio T M

2018-03-20

Cerebral malaria (CM) is a multifactorial syndrome involving an exacerbated proinflammatory status, endothelial cell activation, coagulopathy, hypoxia, and accumulation of leukocytes and parasites in the brain microvasculature. Despite significant improvements in malaria control, 15% of mortality is still observed in CM cases, and 25% of survivors develop neurologic sequelae for life-even after appropriate antimalarial therapy. A treatment that ameliorates CM clinical signs, resulting in complete healing, is urgently needed. Previously, we showed a hyperbaric oxygen (HBO)-protective effect against experimental CM. Here, we provide molecular evidence that HBO targets brain endothelial cells by decreasing their activation and inhibits parasite and leukocyte accumulation, thus improving cerebral microcirculatory blood flow. HBO treatment increased the expression of aryl hydrocarbon receptor over hypoxia-inducible factor 1-α (HIF-1α), an oxygen-sensitive cytosolic receptor, along with decreased indoleamine 2,3-dioxygenase 1 expression and kynurenine levels. Moreover, ablation of HIF-1α expression in endothelial cells in mice conferred protection against CM and improved survival. We propose that HBO should be pursued as an adjunctive therapy in CM patients to prolong survival and diminish deleterious proinflammatory reaction. Furthermore, our data support the use of HBO in therapeutic strategies to improve outcomes of non-CM disorders affecting the brain.-Bastos, M. F., Kayano, A. C. A. V., Silva-Filho, J. L., Dos-Santos, J. C. K., Judice, C., Blanco, Y. C., Shryock, N., Sercundes, M. K., Ortolan, L. S., Francelin, C., Leite, J. A., Oliveira, R., Elias, R. M., Câmara, N. O. S., Lopes, S. C. P., Albrecht, L., Farias, A. S., Vicente, C. P., Werneck, C. C., Giorgio, S., Verinaud, L., Epiphanio, S., Marinho, C. R. F., Lalwani, P., Amino, R., Aliberti, J., Costa, F. T. M. Inhibition of hypoxia-associated response and kynurenine production in response to hyperbaric oxygen

Severe pulmonary edema following hyperbaric oxygen therapy for acute carbon monoxide poisoning: a case report and clinical experience.

PubMed

Fan, Danfeng; Lv, Yan; Hu, Huijun; Pan, Shuyi

2017-01-01

Pulmonary edema following hyperbaric oxygen (HBO₂) therapy is a rare clinical phenomenon. This case report describes such a patient - a 56-year-old woman who suffered from severe pulmonary edema after HBO₂ therapy for carbon monoxide (CO) poisoning. Patient experienced ecphysesis and dyspnea suddenly after HBO₂ therapy (100% oxygen at 0.25 MPa, for 60 minutes with a five-minute air break and decompression at 0.01 MPa/minute). Post therapy her heart rate (HR), blood pressure (BP), respiratory rate (RR) and oxygen saturation (SO₂) were 140 bpm, 60/40 mmHg, 38 bpm and 84%, respectively. Diagnoses of acute pulmonary edema and shock were made. Various treatments including antishock, tracheal intubation, mechanical ventilation for respiratory support, a diuretic, dexamethasone, asthma relief, and acidosis correction were administered. Pulmonary computed tomography (CT) indicated significant pulmonary edema. Due to active treatment, the patient showed gradual improvement. Pulmonary CT re-examination showed pulmonary edema markedly improved. At the two-year follow-up, the patient reported no abnormal mental or neurological symptoms. Acute pulmonary edema is rare but can lead to serious side effects of HBO₂ therapy in patients with severe acute CO poisoning. This complication must be must considered when administering HBO₂ therapy to patients with severe CO poisoning.

An overview of protective strategies against ischemia/reperfusion injury: The role of hyperbaric oxygen preconditioning.

PubMed

Hentia, Ciprian; Rizzato, Alex; Camporesi, Enrico; Yang, Zhongjin; Muntean, Danina M; Săndesc, Dorel; Bosco, Gerardo

2018-05-01

Ischemia/reperfusion (I/R) injury, such as myocardial infarction, stroke, and peripheral vascular disease, has been recognized as the most frequent causes of devastating disorders and death currently. Protective effect of various preconditioning stimuli, including hyperbaric oxygen (HBO), has been proposed in the management of I/R. In this study, we searched and reviewed up-to-date published papers to explore the pathophysiology of I/R injury and to understand the mechanisms underlying the protective effect of HBO as conditioning strategy. Animal study and clinic observation support the notion that HBO therapy and conditioning provide beneficial effect against the deleterious effects of postischemic reperfusion. Several explanations have been proposed. The first likely mechanism may be that HBO counteracts hypoxia and reduces I/R injury by improving oxygen delivery to an area with diminished blood flow. Secondly, by reducing hypoxia-ischemia, HBO reduces all the pathological events as a consequence of hypoxia, including tissue edema, increased affective area permeability, postischemia derangement of tissue metabolism, and inflammation. Thirdly, HBO may directly affect cell apoptosis, signal transduction, and gene expression in those that are sensitive to oxygen or hypoxia. HBO provides a reservoir of oxygen at cellular level not only carried by blood, but also by diffusion from the interstitial tissue where it reaches high concentration that may last for several hours, improves endothelial function and rheology, and decreases local inflammation and edema. Evidence suggests the benefits of HBO when used as a preconditioning stimulus in the setting of I/R injury. Translating the beneficial effects of HBO into current practice requires, as for the "conditioning strategies", a thorough consideration of risk factors, comorbidities, and comedications that could interfere with HBO-related protection.

Hyperbaric treatment for children with autism: a multicenter, randomized, double-blind, controlled trial

PubMed Central

Rossignol, Daniel A; Rossignol, Lanier W; Smith, Scott; Schneider, Cindy; Logerquist, Sally; Usman, Anju; Neubrander, Jim; Madren, Eric M; Hintz, Gregg; Grushkin, Barry; Mumper, Elizabeth A

2009-01-01

Background Several uncontrolled studies of hyperbaric treatment in children with autism have reported clinical improvements; however, this treatment has not been evaluated to date with a controlled study. We performed a multicenter, randomized, double-blind, controlled trial to assess the efficacy of hyperbaric treatment in children with autism. Methods 62 children with autism recruited from 6 centers, ages 2–7 years (mean 4.92 ± 1.21), were randomly assigned to 40 hourly treatments of either hyperbaric treatment at 1.3 atmosphere (atm) and 24% oxygen ("treatment group", n = 33) or slightly pressurized room air at 1.03 atm and 21% oxygen ("control group", n = 29). Outcome measures included Clinical Global Impression (CGI) scale, Aberrant Behavior Checklist (ABC), and Autism Treatment Evaluation Checklist (ATEC). Results After 40 sessions, mean physician CGI scores significantly improved in the treatment group compared to controls in overall functioning (p = 0.0008), receptive language (p < 0.0001), social interaction (p = 0.0473), and eye contact (p = 0.0102); 9/30 children (30%) in the treatment group were rated as "very much improved" or "much improved" compared to 2/26 (8%) of controls (p = 0.0471); 24/30 (80%) in the treatment group improved compared to 10/26 (38%) of controls (p = 0.0024). Mean parental CGI scores significantly improved in the treatment group compared to controls in overall functioning (p = 0.0336), receptive language (p = 0.0168), and eye contact (p = 0.0322). On the ABC, significant improvements were observed in the treatment group in total score, irritability, stereotypy, hyperactivity, and speech (p < 0.03 for each), but not in the control group. In the treatment group compared to the control group, mean changes on the ABC total score and subscales were similar except a greater number of children improved in irritability (p = 0.0311). On the ATEC, sensory/cognitive awareness significantly improved (p = 0.0367) in the treatment group

Hyperbaric Oxygen Therapy Can Diminish Fibromyalgia Syndrome – Prospective Clinical Trial

PubMed Central

Efrati, Shai; Golan, Haim; Bechor, Yair; Faran, Yifat; Daphna-Tekoah, Shir; Sekler, Gal; Fishlev, Gregori; Ablin, Jacob N.; Bergan, Jacob; Volkov, Olga; Friedman, Mony; Ben-Jacob, Eshel; Buskila, Dan

2015-01-01

Background Fibromyalgia Syndrome (FMS) is a persistent and debilitating disorder estimated to impair the quality of life of 2–4% of the population, with 9:1 female-to-male incidence ratio. FMS is an important representative example of central nervous system sensitization and is associated with abnormal brain activity. Key symptoms include chronic widespread pain, allodynia and diffuse tenderness, along with fatigue and sleep disturbance. The syndrome is still elusive and refractory. The goal of this study was to evaluate the effect of hyperbaric oxygen therapy (HBOT) on symptoms and brain activity in FMS. Methods and Findings A prospective, active control, crossover clinical trial. Patients were randomly assigned to treated and crossover groups: The treated group patients were evaluated at baseline and after HBOT. Patients in the crossover-control group were evaluated three times: baseline, after a control period of no treatment, and after HBOT. Evaluations consisted of physical examination, including tender point count and pain threshold, extensive evaluation of quality of life, and single photon emission computed tomography (SPECT) imaging for evaluation of brain activity. The HBOT protocol comprised 40 sessions, 5 days/week, 90 minutes, 100% oxygen at 2ATA. Sixty female patients were included, aged 21–67 years and diagnosed with FMS at least 2 years earlier. HBOT in both groups led to significant amelioration of all FMS symptoms, with significant improvement in life quality. Analysis of SPECT imaging revealed rectification of the abnormal brain activity: decrease of the hyperactivity mainly in the posterior region and elevation of the reduced activity mainly in frontal areas. No improvement in any of the parameters was observed following the control period. Conclusions The study provides evidence that HBOT can improve the symptoms and life quality of FMS patients. Moreover, it shows that HBOT can induce neuroplasticity and significantly rectify abnormal

Effects of positive end-expiratory pressure on intracranial pressure in mechanically ventilated dogs under hyperbaric oxygenation.

PubMed

Sun, Qing; Wu, Di; Yu, Tao; Yang, Ying; Wei, Li; Lv, Fuxiang; Gao, Guangkai

2014-01-01

Mechanical ventilation with positive end-expiratory pressure (PEEP) has been advocated as an essential life support for critical patients. However, its side effect, which is demonstrated by an elevation of intracranial pressure (ICP) under normobaric (NBO2) conditions, is potentially detrimental to patients. Hyperbaric oxygen (HBO2) therapy, on the other hand, is frequently applied for the same group of patients, and its efficacy is shown by maintaining a higher PaO2 and a reduced ICP. Our study investigated the effect of HBO2 and NBO2 on ICP with or without PEEP ventilation on healthy dogs by comparing cerebrospinal fluid pressure (CSFP) and concluded that the elevation of PEEP resulted in a significant increase of ICP (CSFP) under both conditions (p < 0.05). HBO2 leads to a lower ICP increase compared to the NBO2 group. Under the same level of PEEP, the joint use of PEEP and HBO2 is safe and highly practical in clinical medicine.

The Mechanism of Hyperbaric Oxygen Therapy in the Treatment of Chronic Wounds and Diabetic Foot Ulcers.

PubMed

Johnston, Benjamin R; Ha, Austin Y; Brea, Bielinsky; Liu, Paul Y

2016-02-01

Non-healing wounds are a growing public health concern, and more than $25 billion per year in the US are spent caring for patients with chronic wounds. Many of these patients are referred to specialized wound centers, where hyperbaric oxygen therapy (HBO2T) has become a mainstay in healing wounds, especially diabetic foot ulcers (DFU). However, it is costly, with a typical course of therapy running into the tens of thousands of dollars. Presently, as many as 30-40% of DFU patients with Wagner's Grade 3 and 4 ulcers treated with HBO2T fail to heal by 24 weeks. Unfortunately, the patient will have already received lengthy therapy (30-60 daily treatments over 6-10 week time period) before having the wound deemed non-responsive. Currently, practitioners employ a combination of clinical markers, diagnostic testing and a four-week preliminary healing response, but this approach is inaccurate and delays definitive identification of HBO2T responder and non-responder phenotypes.

SirT1 mediates hyperbaric oxygen preconditioning-induced ischemic tolerance in rat brain

PubMed Central

Yan, Wenjun; Fang, Zongping; Yang, Qianzi; Dong, Hailong; Lu, Yan; Lei, Chong; Xiong, Lize

2013-01-01

Our previous studies have shown that hyperbaric oxygen preconditioning (HBO-PC) induces tolerance to cerebral ischemia/reperfusion (I/R). This study aimed to investigate whether SirT1, a class III histone deacetylase, is involved in neuroprotection elicited by HBO-PC in animal and cell culture models of ischemia. Rats were subjected to middle cerebral artery occlusion for 120 minutes after HBO-PC (once a day for 5 days). Primary cultured cortical neurons were exposed to 2 hours of HBO-PC after 2 hours of oxygen–glucose deprivation (OGD). We showed that HBO-PC increased SirT1 protein and mRNA expression, promoted neurobehavioral score, reduced infarct volume, and improved morphology at 24 hours and 7 days after cerebral I/R. Neuroprotection of HBO-PC was attenuated by SirT1 inhibitor EX527 and SirT1 knockdown by short interfering RNA (siRNA), whereas it was mimicked by SirT1 activator resveratrol. Furthermore, HBO-PC enhanced SirT1 expression and cell viability and reduced lactate dehydrogenase release 24 hours after OGD/re-oxygenation. The neuroprotective effect of HBO-PC was emulated through upregulating SirT1 and, reversely, attenuated through downregulating SirT1. The modulation of SirT1 was made by adenovirus infection carrying SirT1 or SirT1 siRNA. Besides, SirT1 increased B-cell lymphoma 2 (Bcl-2) expression and decrease cleaved caspase 3. These results indicate that SirT1 mediates HBO-PC-induced tolerance to cerebral I/R through inhibition of apoptosis. PMID:23299244

[Impact of oxygen toxic action on the erythrocyte membrane and possibility of estimating central nervous system function disturbances].

PubMed

Belić, Branislava; Cincović, Marko R

2011-07-01

BACKGROUND/AIM; Prolonged exposure to hyperbaric oxygen leads to changes of erythrocytes shape as a consequence of toxic effects of oxygen on the erythrocyte membrane. The aim of this study was to examine the association between occurance of pathological forms of erythrocytes at different time from the start of hyperbaric oxygenation and the moment of convulsions occurrence, an interrelationship of different pathological forms of erythrocytes during exposure to hyperbaric oxygenation, as well as the correlation between the presence of ruptured erythrocytes and function of central nervous system (CNS) after completion of hyperbaric treatment. Sixty laboratory mice, Mus musculus, were exposed to the wholly-oxygen pressure of 3.5 absolute atmospheres (ATA). Blood was collected at the 32nd, 34th, 36th, 38th and 40th minutes after the exposure to oxygen. Pathological forms of erythrocytes were examined by electron microscopy. A moment of convulsions occurrence was registered in all animals. After decompression neurological examinations of experimental animals were perfomed. The Pearson's coefficient of correlation, and linear regression equations for the parameters outlined in the aim of the study were calculated. Hyperbaric oxygen caused damages of erythrocytes at the 34th minute after beginning of the treatment. Various forms of abnormal red blood cells occured, and immediately before the occurrence of irreversible changes (erythrocyte membrane rupture) echinocyte shape was dominated. A significant correlation between the number of damaged red blood cells at 34th minute and their number at the 36th, 38th and 40th minute was found. Convulsions were diagnosed significantly earlier in mice with a greater number of damaged red blood cells (p < 0.01). There was a negative correlation between the number of irreversiblly damaged red blood cells (ruptured) at the 40th minute and neurological score in the studied animals (p < 0.05). The analysis of altered erythrocytes during

Coma reversal with cerebral dysfunction recovery after repetitive hyperbaric oxygen therapy for severe carbon monoxide poisoning.

PubMed

Dean, B S; Verdile, V P; Krenzelok, E P

1993-11-01

The accepted beneficial effects of hyperbaric oxygen (HBO) include a greatly diminished carboxyhemoglobin (COHgb) half-life, enhanced tissue clearance of residual carbon monoxide (CO), reduced cerebral edema, and reversal of cytochrome oxidase inhibition, and prevention of central nervous system lipid peroxidation. Debate regarding the criteria for selection of HBO versus 100% normobaric oxygen therapy continues, and frequently is based solely on the level of COHgb saturation. Patients who manifest signs of serious CO intoxication (unconsciousness, neuropsychiatric symptoms, cardiac or hemodynamic instability) warrant immediate HBO therapy. An unresponsive 33-year-old woman was found in a closed garage, inside her automobile with the ignition on. Her husband admitted to seeing her 6 hours before discovery. 100% normobaric oxygen was administered in the prehospital and emergency department settings. The patient had an initial COHgb saturation of 46.7%, a Glasgow coma score of 3, and was transferred for HBO therapy. Before HBO therapy, the patient remained unresponsive and demonstrated decerebrate posturing and a positive doll's eyes (negative oculocephalic reflex). The electroencephalogram pattern suggested bilateral cerebral dysfunction consistent with a toxic metabolic or hypoxic encephalopathy. The patient underwent HBO therapy at 2.4 ATA for 90 minutes twice a day for 3 consecutive days. On day 7, the patient began to awaken, was weaned from ventilatory support, and was not soon verbalizing appropriately. A Folstein mental status examination showed a score of 26 of 30. Neurological examination demonstrated mild residual left upper extremity weakness and a normal gait. There was no evidence of significant neurological sequelae at 1 month follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Potential roles of hyperbaric oxygenation in the treatments of brain tumors.

PubMed

Kohshi, Kiyotaka; Beppu, Takaaki; Tanaka, Katsuyuki; Ogawa, Kazuhiko; Inoue, Osamu; Kukita, Ichiro; Clarke, Richard E

2013-01-01

Over the past 50 years hyperbaric oxygen (HBO2) therapy has been used in a wide variety of medical conditions, and one of them is cancer. Many clinical studies have been conducted to evaluate potential therapeutic effects of HBO2 as a part of cancer treatment. This review briefly summaries the potential role of HBO2 therapy in the treatment of malignant tumors and radiation injury of the brain. HBO2 therapy is used for the enhancement of radiosensitivity in the treatment of some cancers, including malignant brain tumors. Radiotherapy within 15 minutes following HBO2 exposure, a relatively new treatment regimen, has been studied at several institutes and has demonstrated promising clinical results for malignant gliomas of the brain. HBO2 therapy also increases sensitivity to some antineoplastic agents; non-randomized clinical trials using carboplatin-based chemotherapy combined with HBO2 show a significant advantage in survival for recurrent malignant gliomas. The possibilities of combining HBO2 therapy with radiotherapy and/or chemotherapy to overcome newly diagnosed and recurrent malignant gliomas deserve extensive clinical trials. HBO2 therapy also shows promising potential for the treatment and/or prevention of radiation injury of the brain after stereotactic radiosurgery for brain lesions. The possibilities with HBO2 to enhance the therapeutic effect of irradiation per se, and to even increase the radiation dose if there are ways to combat the side effects, should boost new scientific interest into the whole field of oncology looking for new armamentaria to fight cancer.

Hyperbaric Oxygen Therapy for the Treatment of Diabetic Foot Ulcers: A Health Technology Assessment

PubMed Central

Lambrinos, Anna; Chan, Brian; Wells, David; Holubowich, Corinne

2017-01-01

Background About 15% to 25% of people with diabetes will develop a foot ulcer. These wounds are often resistant to healing; therefore, people with diabetes experience lower limb amputation at about 20 times the rate of people without diabetes. If an ulcer does not heal with standard wound care, other therapeutic interventions are offered, one of which is hyperbaric oxygen therapy (HBOT). However, the effectiveness of this therapy is not clearly known. The objectives of this health technology assessment were to assess the safety, clinical effectiveness, and cost-effectiveness of standard wound care plus HBOT versus standard wound care alone for the treatment of diabetic foot ulcers. We also investigated the preferences and perspectives of people with diabetic foot ulcers through lived experience. Methods We performed a review of the clinical and economic literature for the effectiveness and cost-effectiveness of hyperbaric oxygen therapy, as well as the budget impact of HBOT from the perspective of the Ministry of Health and Long-Term Care. We assessed the quality of the body of clinical evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. To better understand the preferences, perspectives, and values of patients with diabetic foot ulcers and their experience with HBOT, we conducted interviews and administered an online survey. Results Seven randomized controlled trials and one nonrandomized controlled trial met the inclusion criteria. Comparing standard wound care plus HBOT with standard wound care alone, we found mixed results for major amputation rates (GRADE quality of evidence: low), a significant difference in favour of standard wound care plus HBOT on ulcers healed (GRADE quality of evidence: low), and no difference in terms of adverse events (GRADE quality of evidence: moderate). There is a large degree of uncertainty associated with the evaluation of the cost-effectiveness of standard wound

Functional recovery in rat spinal cord injury induced by hyperbaric oxygen preconditioning.

PubMed

Lu, Pei-Gang; Hu, Sheng-Li; Hu, Rong; Wu, Nan; Chen, Zhi; Meng, Hui; Lin, Jiang-Kai; Feng, Hua

2012-12-01

It is a common belief that neurosurgical interventions can cause inevitable damage resulting from the procedure itself in surgery especially for intramedullary spinal cord tumors. The present study was designed to examine if hyperbaric oxygen preconditioning (HBO-PC) was neuroprotective against surgical injuries using a rat model of spinal cord injury (SCI). Sprague-Dawley rats were randomly divided into three groups: HBO-PC group, hypobaric hypoxic preconditioning (HH-PC) control group, and normobaric control group. All groups were subjected to SCI by weight drop device. Rats from each group were examined for neurological behavior and electrophysiological function. Tissue sections were analyzed by using immunohistochemistry, TdT-mediated dUTP-biotin nick end labeling, and axonal tract tracing. Significant neurological deficits were observed after SCI and HBO-PC and HH-PC improved neurological deficits 1 week post-injury. The latencies of motor-evoked potential and somatosensory-evoked potential were significantly delayed after SCI, which was attenuated by HBO-PC and HH-PC. Compared with normobaric control group, pretreatment with HBO and hypobaric hypoxia significantly reduced the number of TdT-mediated dUTP-biotin nick end labeling-positive cells, and increased nestin-positive cells. HBO-PC and HH-PC enhanced axonal growth after SCI. In conclusion, preconditioning with HBO and hypobaric hypoxia can facilitate functional recovery and suppress cell apoptosis after SCI and may prove to be a useful preventive strategy to neurosurgical SCI.

Requests for emergency hyperbaric oxygen treatment for carbon monoxide poisoning in Ankara, Turkey.

PubMed

Özgök-Kangal, Münïre Kübra; Karatop-Cesur, Iclal; Akcali, Gökhan; Yildiz, Senol; Uzun, Günalp

2016-09-01

Carbon monoxide (CO) poisoning is common in Turkey. Our department is the main provider of emergency hyperbaric oxygen therapy (HBOT) in Ankara and neighboring cities. In this study, we analyzed the characteristics of CO-poisoned patients who were referred by phone to our department for emergency HBOT. We retrospectively reviewed the records of phone consultations with emergency departments regarding the need for treatment of CO-poisoned patients with HBOT between 14 January 2014 and 14 January 2015. The following information was extracted from medical records: age, gender, CO source, exposure duration, carboxyhemoglobin (COHb) level, symptoms, electrocardiography (ECG) findings, cardiac enzymes, pregnancy, the distance of referring hospital to our centre, time between admission and consultation and HBOT decision. Over the one-year period, 562 patients with CO poisoning were referred for HBOT. We recommended HBOT for 289 (51%) patients. HBOT was recommended for 58% (n = 194) of the patients with COHb ≥ 25%, 72% (n = 163) of the patients with a history of syncope, 67% (n = 35) of the patients with ECG abnormality, and 67% (n = 14) of pregnant patients. Patients for whom HBOT was not recommended despite having positive signs of severe poisoning were referred significantly later compared to patients for whom HBOT was recommended. We found that the duration from admission to an emergency department to HBOT consultation affected our decision-making.

Hyperbaric oxygenation therapy for crush injuries reduces the risk of complications: research report.

PubMed

Yamada, Noriaki; Toyoda, Izumi; Doi, Tomoaki; Kumada, Keisuke; Kato, Hisaaki; Yoshida, Shozo; Shirai, Kunihiro; Kanda, Norihide; Ogura, Shinji

2014-01-01

Hyperbaric oxygen (HBO2) therapy has been adopted for crush injuries, but there are few studies supporting its use. We therefore investigated the effects of HBO2 on management of patients with complicated crush injuries. This historic cohort study included patients with crush injuries and open fractures with severities greater than or equal to Gustilo class IIIA. We divided the patients into two groups: Control and HBO2. The control group received conventional treatment, while the HBO2 group received conventional treatment plus HBO2. We compared the groups with respect to the incidence of infection, need for additional surgery, and length of intensive care unit (ICU) and hospital stays. There were 16 patients in the HBO2 group and 13 in the control group. There were no patients with infections in the HBO2 group, whereas in the control group six patients had infections and five needed another drainage procedure. These incidences were significantly lower in the HBO2 group (p = 0.003 and 0.013). However, the durations of ICU and hospital stays were similar across the two groups. HBO2 is effective in the management of crush injuries from the viewpoint of reducing complications and reoperations. These observations should be verified in additional studies with larger sample sizes because the patient number is limited.

Hydrogen peroxide ingestion associated with portal venous gas and treatment with hyperbaric oxygen: a case series and review of the literature.

PubMed

French, Loren Keith; Horowitz, B Zane; McKeown, Nathanael J

2010-07-01

Ingestion of concentrated hydrogen peroxide (H(2)O(2)) has been associated with venous and arterial gas embolic events, hemorrhagic gastritis, gastrointestinal bleeding, shock, and death. Although H(2)O(2) is generally considered a benign ingestion in low concentrations, case reports have described serious toxicity following high concentration exposures. Hyperbaric oxygen (HBO) has been used with success in managing patients suffering from gas embolism with and without manifestations of ischemia. Poison center records were searched from July 1999 to January 2010 for patients with H(2)O(2) exposure and HBO treatment. Cases were reviewed for the concentration of H(2)O(2), symptoms, CT scan findings of portal gas embolism, HBO treatment, and outcome. RESULTS; Eleven cases of portal gas embolism were found. Ages ranged from 4 to 89 years. All but one ingestion was accidental in nature. In 10 cases 35% H(2)O(2) was ingested and in 1 case 12% H(2)O(2) was ingested. All abdominal CT scans demonstrated portal venous gas embolism in all cases. Hyperbaric treatment was successful in completely resolving all portal venous gas bubbles in nine patients (80%) and nearly resolving them in two others. Ten patients were able to be discharged home within 1 day, and one patient had a 3.5-day length of stay. HBO was successful in resolving portal venous gas embolism from accidental concentrated H(2)O(2) ingestions.

Application of Hyperbaric Oxygen Reduce Oxidative Damage of Plasmatic Carbonyl Proteins and 8-OHdG by Activating Glutathion Peroxidase.

PubMed

Matzi, Veronika; Greilberger, Joachim F; Lindenmann, Joerg; Neuboeck, Nicole; Nuhsbaumer, Stephan; Zelzer, Sieglinde; Tafeit, Erwin; Maier, Alfred; Smolle-Juettner, Maria-Frey

2015-01-01

It is postulated that application of hyperbaric oxygenation may induce the production of radicals after HBO. Higher oxygenation and transport of oxygen increase the mitochondrial energy turnover, whereas inner mitochondrial radical formation decreases. Several markers of oxidative stress in healthy volunteers (n = 21), including plasma carbonyl proteins (CP), malondialdehyde (MDA), oxidized LDL (oxLDL), 8-hydroxy-deoxyguanosine (8-OHdG), and erythrocyte glutathione peroxidase (GPx) activity are measured before, during, and after HBO. Median plasma concentrations of CP decreased significantly during HBO compared to CP levels before HBO (from 77.1 to 61.7 pmol/mg; p < 0.001) and increased again after HBO (to 78.1 pmol/mg; p = 0.035). 8-OHdG decreased significantly during HBO (8.1 ng/mL; p < 0.001) and remained constant after HBO (8.1 ng/mL) compared to "before HBO" (9.4 ng/mL). MDA increased significantly from 0.92 μM (before HBO) to 1.26 μM (during HBO, p < 0.01) and decreased again to 1.00 μM (after HBO, p = 0.023). Erythrocyte GPx activity also increased significantly during HBO (26.5 ± 14.7; p = 0.005), but not after HBO (25.6 ± 17.2 IU/mg). A negative correlation was observed between GPx and MDA only during HBO (r = -0.518; p = 0.016). We assume that higher oxygen consumption decreases, on the one hand, the inner mitochondrial generation of free radicals and, on the other, RONS by activation of detoxifying enzymes like GPx.

Oxygen, a Key Factor Regulating Cell Behavior during Neurogenesis and Cerebral Diseases.

PubMed

Zhang, Kuan; Zhu, Lingling; Fan, Ming

2011-01-01

Oxygen is vital to maintain the normal functions of almost all the organs, especially for brain which is one of the heaviest oxygen consumers in the body. The important roles of oxygen on the brain are not only reflected in the development, but also showed in the pathological processes of many cerebral diseases. In the current review, we summarized the oxygen levels in brain tissues tested by real-time measurements during the embryonic and adult neurogenesis, the cerebral diseases, or in the hyperbaric/hypobaric oxygen environment. Oxygen concentration is low in fetal brain (0.076-7.6 mmHg) and in adult brain (11.4-53.2 mmHg), decreased during stroke, and increased in hyperbaric oxygen environment. In addition, we reviewed the effects of oxygen tensions on the behaviors of neural stem cells (NSCs) in vitro cultures at different oxygen concentration (15.2-152 mmHg) and in vivo niche during different pathological states and in hyperbaric/hypobaric oxygen environment. Moderate hypoxia (22.8-76 mmHg) can promote the proliferation of NSCs and enhance the differentiation of NSCs into the TH-positive neurons. Next, we briefly presented the oxygen-sensitive molecular mechanisms regulating NSCs proliferation and differentiation recently found including the Notch, Bone morphogenetic protein and Wnt pathways. Finally, the future perspectives about the roles of oxygen on brain and NSCs were given.

Umbilical cord-derived mesenchymal stem cell transplantation combined with hyperbaric oxygen treatment for repair of traumatic brain injury

PubMed Central

Zhou, Hai-xiao; Liu, Zhi-gang; Liu, Xiao-jiao; Chen, Qian-xue

2016-01-01

Transplantation of umbilical cord-derived mesenchymal stem cells (UC-MSCs) for repair of traumatic brain injury has been used in the clinic. Hyperbaric oxygen (HBO) treatment has long been widely used as an adjunctive therapy for treating traumatic brain injury. UC-MSC transplantation combined with HBO treatment is expected to yield better therapeutic effects on traumatic brain injury. In this study, we established rat models of severe traumatic brain injury by pressurized fluid (2.5–3.0 atm impact force). The injured rats were then administered UC-MSC transplantation via the tail vein in combination with HBO treatment. Compared with monotherapy, aquaporin 4 expression decreased in the injured rat brain, but growth-associated protein-43 expression, calaxon-like structures, and CM-Dil-positive cell number increased. Following combination therapy, however, rat cognitive and neurological function significantly improved. UC-MSC transplantation combined with HBO therapyfor repair of traumatic brain injury shows better therapeutic effects than monotherapy and significantly promotes recovery of neurological functions. PMID:26981097

Hyperbaric oxygen for the treatment of the rare combination of central retinal vein occlusion and cilioretinal artery occlusion.

PubMed

Celebi, Ali Riza Cenk; Kilavuzoglu, Ayse Ebru; Altiparmak, Ugur Emrah; Cosar, C Banu; Ozkiris, Abdullah

2016-03-01

A 43-year-old male presented with sudden onset of painless, blurred vision in his left eye. Dilated fundoscopic examination showed signs consistent with the diagnosis of a combination of central retinal vein occlusion (CRVO) and cilioretinal artery occlusion (CLRAO). He received daily 2-h sessions of hyperbaric oxygen treatment (HBOT), 253 kPa for 14 days. At the end of the HBOT course, the patient's left visual acuity had improved from 20/200 to 20/20. Dilated fundoscopic examination showed that the intra-retinal haemorrhages in the entire retina and the retinal whitening along the course of the CLRA seen at presentation had completely resolved. The combination of CLRAO and CRVO comprises a discrete clinical entity. Even though there are many hypotheses concerning this condition, it is most likely the result of elevated intraluminal pressure in the retinal capillaries due to CRVO that exceeds the pressure in the CLRA. HBOT may be an effective treatment for CRVO-associated CLRAO.

Characterisation of fume from hyperbaric welding operations

NASA Astrophysics Data System (ADS)

Ross, John A. S.; Semple, Sean; Duffin, Rodger; Kelly, Frank; Seldmann, Joerg; Raab, Andrea

2009-02-01

We report preliminary work characterising dust from hyperbaric welding trials carried out at increased pressure in a helium and oxygen atmosphere. Particle size and concentration were measured during welding. Samples for quartz and metal analysis and toxicity assessment were taken from a filter in the local fume extraction system. The residue of dust after metal extraction by nitric acid in hydrogen peroxide predominantly a non-metallic white powder assumed to be dust from welding rod coatings and thermal insulation material. Metallic analysis showed predominantly calcium, from the welding rod coating, and period 4 transition metals such as iron, manganese, magnesium and titanium (inductively coupled mass spectrometry, Agilent 7500c). The presence of zirconium indicated a contribution from grinding. The fume was nanoparticulate in nature with a mean particle diameter of 20-30 nm (MSI Inc WPS 1000XP). It showed an intermediate level of oxidative potential regarding the low-molecular weight respiratory tract lining fluid antioxidants ascorbate and glutathione and caused release of the inflammatory marker IL-8 in a human lung A 549 epithelial cell culture with no indication of cytotoxicity. The study findings have strong implications for the measurement techniques needed to assess fume exposure in hyperbaric welding and the provision of respiratory protection.

Hyperbaric oxygen increases tissue-plasminogen activator-induced thrombolysis in vitro, and reduces ischemic brain damage and edema in rats subjected to thromboembolic brain ischemia.

PubMed

Chazalviel, Laurent; Haelewyn, Benoit; Degoulet, Mickael; Blatteau, Jean-Eric; Vallée, Nicolas; Risso, Jean-Jacques; Besnard, Stéphane; Abraini, Jacques H

2016-01-01

Recent data have shown that normobaric oxygen (NBO) increases the catalytic and thrombolytic efficiency of recombinant tissue plasminogen activator (rtPA) in vitro , and is as efficient as rtPA at restoring cerebral blood flow in rats subjected to thromboembolic brain ischemia. Therefore, in the present study, we studied the effects of hyperbaric oxygen (HBO) (i) on rtPA-induced thrombolysis in vitro and (ii) in rats subjected to thromboembolic middle cerebral artery occlusion-induced brain ischemia. HBO increases rtPA-induced thrombolysis in vitro to a greater extent than NBO; in addition, HBO treatment of 5-minute duration, but not of 25-minute duration, reduces brain damage and edema in vivo . In line with the facilitating effect of NBO on cerebral blood flow, our findings suggest that 5-minute HBO could have provided neuroprotection by promoting thrombolysis. The lack of effect of HBO exposure of longer duration is discussed.

A modified protocol for early treatment of osteomyelitis and osteoradionecrosis of the mandible.

PubMed

Aitasalo, K; Niinikoski, J; Grénman, R; Virolainen, E

1998-08-01

The treatment of osteoradionecrosis (ORN) and early chronic osteomyelitis (COM) of the mandible and maxilla is controversial. Hyperbaric oxygen (HBO) at two to three times the atmospheric pressure at sea level can result in tissue oxygen tension of almost 400 mmHg. Herewith HBO increases oxygen supply in hypoxic tissue, thus inducing fibroblastic proliferation and capillary formation. From 1981 to 1991, we used a monoplace chamber and since 1992, we have also had a multiplace chamber for HBO treatment. Hyperbaric oxygen was given at 2.5-2.8 atmosphere absolute pressure (ATA) for 90-120 minutes, once per day. The patients had five to 10 preoperative and five to seven postoperative sessions. Surgical therapy consisted of decortication of the affected bone, subsequently covered with a free periosteal transplant from the tibia. Thirty-six patients with ORN and 33 with COM of the mandible and maxilla was treated with this protocol. The median follow-up time in this material is 34 months, with a minimum of 10 months. Thirty-six ORN patients (92%) and 26 COM patients (79%) have remained symptom-free after the first treatment period. Three failed ORN patients were successfully treated with a free microvascular flap. The seven failed COM patients have been retreated, and five of them have occasional clinical symptoms. Hyperbaric oxygen is a promising adjunct to surgery in the treatment of mandibular and maxillary ORN and COM. Using this protocol, the necessary HBO treatment sessions have been reduced from earlier protocols, without adverse effect on the outcome.

Hyperbaric index in the primary prevention of hypertensive complications in high-risk pregnancy.

PubMed

Otero González, Alfonso; Uribe Moya, Silvia; Arenas Moncaleano, Ivan Gilberto; Borrajo Prol, María Paz; García García, María Jesús; López Sánchez, Luis

2015-01-01

Preeclampsia (PE) is a major cause of fetal morbidity and mortality. In the Western World, PE affects 2-7% of pregnancies and is responsible for 50,000 deaths annually. Early detection is a priority as it can change the clinical course, but there are no biomarkers or instrumental methods with high sensitivity and specificity. Only the hyperbaric index has a sensitivity and specificity of 99% for early identification of pregnant women at risk of developing PE, but its use is not widespread. To assess the usefulness of the hyperbaric index in the primary prevention of hypertensive pregnancy complications in a public healthcare area. This is a retrospective study of pregnancies that occurred in our area during the period 2007-2012 (N=11,784). The diagnosis was established by the hyperbaric index and pregnant women at risk were treated with ASA at night. In pregnant patients referred to the nephrology clinic (38.2%), diagnosed as high-risk for PE, and treated with 100mg ASA/night (from week 17), the incidence of PE episodes was reduced by 96.94. Copyright © 2015 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

Hyperbaric pressure effects measured by growth of a transplantable tumor in the C3H/HeN mouse.

PubMed

Herndon, B L; Lally, J J

1984-09-01

Both hypobaric exposure at 0.5 atmospheres absolute (ATA) and hyperbaric pressure exposure at 3.5-8 ATA slowed transplantable tumor growth. These experiments detailed the hyperbaric pressure exposure. C3H/HeN-MTV+ mice, bearing the 16/C transplantable murine mammary adenocarcinoma and exposed to 18 days' treatment by a hyperbaric chamber at 3.5-8 ATA, had tumor weights that averaged 50-75% less than the tumor weights in mice caged at ambient ("sea level") pressure. A series of experiments was run to investigate this response to hyperbaric pressure exposure. After mice underwent continuous exposure to 3.5-8 ATA normoxic (normal oxygen) hyperbaric pressure with use of either argon or nitrogen inert gas, which began 3 days after tumor inoculation, tumors were removed at about 3 weeks' growth from these pressure-exposed mice and measured for growth by weighing. Final tumor weight in pressure-exposed experimental mice was significantly less than tumor weight in paired groups of tumor-bearing controls that received no hyperbaric pressure. Tumor weight was inversely related to pressure "dose," although the small pressure range produced an effect at all pressures used. The number of compression-decompression cycles to which the animals were subjected, however, was related positively to tumor weight at necropsy. Continued tumor growth in mice subjected to frequent pressure change (in conjunction with pressure exposure that otherwise limited tumor size) was unexplained by these experiments. The greatest difference between tumor weights in controls and pressure-exposed animals was seen with 2 weeks' continuous pressure exposure. A limited profile of blood tests was performed, and these reflected only minor, expected change in the pressure-exposed experimental animals. The data at hand did not suggest a mechanism by which chronic normoxic hyperbaric pressure limited tumor size.

Long-term exposure to repetitive hyperbaric oxygen results in cumulative oxidative stress in rat lung tissue.

PubMed

Simsek, Kemal; Ay, Hakan; Topal, Turgut; Ozler, Mehmet; Uysal, Bulent; Ucar, Ergun; Acikel, Cengiz H; Yesilyurt, Ozgur; Korkmaz, Ahmet; Oter, Sukru; Yildiz, Senol

2011-02-01

Despite its known benefits, hyperbaric oxygen (HBO) is also reported to enhance the production of reactive oxygen species and can cause oxidative stress in several tissues. Previous studies had shown that HBO-induced oxidative stress is directly proportional to both its exposure pressure and duration. Nevertheless, these studies were usually performed with single-session HBO exposure but its clinical use commonly depends on long-term exposure periods. To clarify the oxidative effect of long-term repetitive HBO in the lung tissue of rats. Male Sprague-Dawley rats were divided into six study groups exposed to consecutive HBO sessions (2.8 atm/90  min) for 5, 10, 15, 20, 30, and 40 days. Animals were sacrificed 24  h after the last HBO session. An additional control group was set to obtain normal data. Lung malondialdehyde (MDA) and carbonylated protein (PCC) levels were determined as measures of oxidative stress along with the activities of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase. None of the measured parameters showed any changes among the groups exposed to 5-15 HBO sessions. However, MDA, PCC, and SOD were found to be significantly increased in the 20 to 40 session groups. These results indicate that repetitive treatment with HBO may cause oxidative stress in critical tissues including the lung. Although HBO-mediated free radicals are accepted to be responsible for the benefits of this therapeutic modality, especially in cases with prolonged exposure, possible injurious effects of supranormal values of bio-oxidative products need to be considered.

Morphological study of rat skin flaps treated with subcutaneous dimethyl sulfoxide combined with hyperbaric oxygen therapy.

PubMed

Almeida, K G; Oliveira, R J; Dourado, D M; Filho, E A; Fernandes, W S; Souza, A S; Araújo, F H S

2015-12-28

This study investigated the effects of hyperbaric oxygen therapy (HBOT) and dimethyl sulfoxide (DMSO) in tissue necrosis, genotoxicity, and cell apoptosis. Random skin flaps were made in 50 male Wistar rats, randomly divided into the following groups. Control group (CT), wherein a rectangular skin section (2 x 8 cm) was dissected from the dorsal muscle layer, preserving the cranial vessels, lifted, and refixed to the bed; distilled water (DW) group, in which DW was injected into the distal half of the skin flap; DMSO group, wherein 5% DMSO was injected; HBOT group, comprising animals treated only with HBOT; and HBOT + DMSO group, comprising animals treated with 100% oxygen at 2.5 atmospheres absolute for 1 h, 2 h after the experiment, daily for 10 consecutive days. A skinflap specimen investigated by microscopy. The percentage of necrosis was not significantly different between groups. The cell viability index was significantly different between groups (P < 0.001): 87.40% (CT), 86.20% (DW), 84.60% (DMSO), 86.60% (DMSO + HBO), and 91% (HBO) (P < 0.001), as was the cell apoptosis index of 12.60 (CT), 12.00 (DW), 15.40 (DMSO), 9.00 (HBO), and 12.00 (DMSO + HBO) (P < 0.001). The genotoxicity test revealed the percentage of cells with DNA damage to be 22.80 (CT), 22.60 (DW), 26.00 (DMSO), 8.80 (DMSO + HBO), and 7.20 (HBO) (P < 0.001). Although the necrotic area was not different between groups, there was a significant reduction in the cellular DNA damage and apoptosis index in the HBOT group.

Oxygen, a Key Factor Regulating Cell Behavior during Neurogenesis and Cerebral Diseases

PubMed Central

Zhang, Kuan; Zhu, Lingling; Fan, Ming

2011-01-01

Oxygen is vital to maintain the normal functions of almost all the organs, especially for brain which is one of the heaviest oxygen consumers in the body. The important roles of oxygen on the brain are not only reflected in the development, but also showed in the pathological processes of many cerebral diseases. In the current review, we summarized the oxygen levels in brain tissues tested by real-time measurements during the embryonic and adult neurogenesis, the cerebral diseases, or in the hyperbaric/hypobaric oxygen environment. Oxygen concentration is low in fetal brain (0.076–7.6 mmHg) and in adult brain (11.4–53.2 mmHg), decreased during stroke, and increased in hyperbaric oxygen environment. In addition, we reviewed the effects of oxygen tensions on the behaviors of neural stem cells (NSCs) in vitro cultures at different oxygen concentration (15.2–152 mmHg) and in vivo niche during different pathological states and in hyperbaric/hypobaric oxygen environment. Moderate hypoxia (22.8–76 mmHg) can promote the proliferation of NSCs and enhance the differentiation of NSCs into the TH-positive neurons. Next, we briefly presented the oxygen-sensitive molecular mechanisms regulating NSCs proliferation and differentiation recently found including the Notch, Bone morphogenetic protein and Wnt pathways. Finally, the future perspectives about the roles of oxygen on brain and NSCs were given. PMID:21503147

Amelioration of rCBF and PbtO2 following TBI at high altitude by hyperbaric oxygen pre-conditioning.

PubMed

Hu, Shengli; Li, Fei; Luo, Haishui; Xia, Yongzhi; Zhang, Jiuquan; Hu, Rong; Cui, Gaoyu; Meng, Hui; Feng, Hua

2010-03-01

Hypobaric hypoxia at high altitude can lead to brain damage and pre-conditioning with hyperbaric oxygen (HBO) can reduce ischemic/hypoxic brain injury. This study investigates the effects of high altitude on traumatic brain injury (TBI) and examines the neuroprotection provided by HBO preconditioning against TBI. Rats were randomly divided into four groups: HBO pre-conditioning group (HBOP, n=10), high altitude group (HA, n=10), plain control group (PC, n=10) and plain sham operation group (sham, n=10). All groups were subjected to head trauma by weight drop device except for the sham group. Rats from each group were examined for neurological function, regional cerebral blood flow (rCBF) and brain tissue oxygen pressure (PbtO(2)) and were killed for analysis by transmission electron microscope. The score of neurological deficits in the HA group was highest, followed by the HBOP group and the PC group, respectively. Both rCBF and PbtO(2) were the lowest in the HA group. Brain morphology and structure seen via the transmission electron microscope was diminished in the HA group, while fewer pathological injuries occurred in the HBOP and PC groups. High altitude aggravates TBI significantly and HBO pre-conditioning can attenuate TBI in rats at high altitude by improvement of rCBF and PbtO(2). Pre-treatment with HBO might be beneficial for people traveling to high altitude locations.

Prevention of Autoimmune Diabetes and Induction of β-Cell Proliferation in NOD Mice by Hyperbaric Oxygen Therapy

PubMed Central

Faleo, Gaetano; Fotino, Carmen; Bocca, Nicola; Molano, R. Damaris; Zahr-Akrawi, Elsie; Molina, Judith; Villate, Susana; Umland, Oliver; Skyler, Jay S.; Bayer, Allison L.; Ricordi, Camillo; Pileggi, Antonello

2012-01-01

We evaluated the effects of hyperbaric oxygen therapy (HOT) on autoimmune diabetes development in nonobese diabetic (NOD) mice. Animals received no treatment or daily 60-min HOT 100% oxygen (HOT-100%) at 2.0 atmospheres absolute and were monitored for diabetes onset, insulitis, infiltrating cells, immune cell function, and β-cell apoptosis and proliferation. Cyclophosphamide-induced diabetes onset was reduced from 85.3% in controls to 48% after HOT-100% (P < 0.005) and paralleled by lower insulitis. Spontaneous diabetes incidence reduced from 85% in controls to 65% in HOT-100% (P = 0.01). Prediabetic mice receiving HOT-100% showed lower insulitis scores, reduced T-cell proliferation upon stimulation in vitro (P < 0.03), increased CD62L expression in T cells (P < 0.04), reduced costimulation markers (CD40, DC80, and CD86), and reduced major histocompatibility complex class II expression in dendritic cells (DCs) (P < 0.025), compared with controls. After autoimmunity was established, HOT was less effective. HOT-100% yielded reduced apoptosis (transferase-mediated dUTP nick-end labeling-positive insulin-positive cells; P < 0.01) and increased proliferation (bromodeoxyuridine incorporation; P < 0.001) of insulin-positive cells compared with controls. HOT reduces autoimmune diabetes incidence in NOD mice via increased resting T cells and reduced activation of DCs with preservation of β-cell mass resulting from decreased apoptosis and increased proliferation. The safety profile and noninvasiveness makes HOT an appealing adjuvant therapy for diabetes prevention and intervention trials. PMID:22566533

Oxygen--a limiting factor for brain recovery.

PubMed

Hadanny, Amir; Efrati, Shai

2015-09-01

Effective brain metabolism is highly dependent on a narrow therapeutic window of oxygen. In major insults to the brain (e.g., intracerebral hemorrhage), a slight decrease in oxygen supply, as occurs in a hypobaric environment at high altitude, has devastating effects on the injured brain tissue. Conversely, increasing brain oxygenation, by the use of hyperbaric oxygen therapy, can improve brain metabolism and its dependent regenerative processes.

Effects of hyperbaric oxygen on crystalline lens and retina in nicotine-exposed rats.

PubMed

Ari, Seyhmus; Nergiz, Yusuf; Cingü, Abdullah Kürşat; Atay, Ahmet Engin; Sahin, Alparslan; Cinar, Yasin; Caca, Ihsan

2013-03-01

To determine histopathological changes on crystalline lens and retina of rats after subcutaneous injection of nicotine and to examine the effects of hyperbaric oxygen (HBO) on these changes related to nicotine exposure. Twenty-eight female Sprague-Dawley rats were enrolled in the study and the rats were divided into four equal sized groups randomly (Group N: the rats exposed only to nicotine, group HB: the rats received only HBO, group N+HB: the rats that underwent to nicotine injection and subsequently received HBO, group C: the control group that neither exposed to nicotine nor received HBO). The rats were sacrificed by decapitation method and all were enucleated immediately after scarification. Tissue samples from crystalline lens, lens capsule, and the retina from the right eyes of the rats were examined by light microscopy. While the histological appearances of the retina and the lens was similar in group HB, group N+HB, and the control group; group N showed some pathological changes like decrement in the retinal ganglion cell density, atrophy of the retinal nerve fiber layer, congestion of the vessels in the optic nerve head, thinning of the internal plexiform layer, thinning of the lens capsule, and transformation of the anterior subcapsular epithelium into squamous epithelia. Subcutaneous injection of nicotine was found to be related with some pathological changes in the retina and lens of the Sprague-Dawley rats. However HBO caused no significant negative effect. Furthermore, the histopathological changes related to nicotine exposure in the lens and retina of the rats recovered by the application of HBO.

Elimination of CT-detected gas bubbles derived from decompression illness with abdominal symptoms after a short hyperbaric oxygen treatment in a monoplace chamber: a case report.

PubMed

Oyaizu, Takuya; Enomoto, Mitsuhiro; Tsujimoto, Toshihide; Kojima, Yasushi; Okawa, Atsushi; Yagishita, Kazuyoshi

2017-01-01

We report the case of a 54-year-old male compressed-air worker with gas bubbles detected by computed tomography (CT). He had complained of strong abdominal pain 30 minutes after decompression after working at a pressure equivalent to 17 meters of sea water for three hours. The initial CT images revealed gas bubbles in the intrahepatic portal vein, pulmonary artery and bilateral femoral vein. After the first hyperbaric oxygen treatment (HBO₂ at 2.5 atmospheres absolute/ATA for 150 minutes), no bubbles were detected on repeat CT examination. The patient still exhibited abdominal distension, mild hypesthesia and slight muscle weakness in the upper extremities. Two sessions of U.S. Navy Treatment Table 6 (TT6) were performed on Days 6 and 7 after onset. The patient recovered completely on Day 7. This report describes the important role of CT imaging in evaluating intravascular gas bubbles as well as eliminating the diagnosis of other conditions when divers or compressed-air workers experience uncommon symptoms of decompression illness. In addition, a short treatment table of HBO₂ using non-TT6 HBO₂ treatment may be useful to reduce gas bubbles and the severity of decompression illness in emergent cases. Copyright© Undersea and Hyperbaric Medical Society.

Clinical Characteristics of Spinal Levobupivacaine: Hyperbaric Compared with Isobaric Solution

PubMed Central

Sanansilp, Vimolluck; Trivate, Travuth; Chompubai, Phakaporn; Visalyaputra, Shusee; Suksopee, Pattipa; Permpolprasert, Ladda; von Bormann, Benno

2012-01-01

We performed a prospective, double-blinded study in 20 patients undergoing gynecologic surgery with lower abdominal incision, to investigate characteristics of intrathecal hyperbaric levobupivacaine compared with isobaric levobupivacaine. We randomly assigned them to receive 3 mL of either isobaric or hyperbaric 0.42% levobupivacaine intrathecally. We found that hyperbaric levobupivacaine, compared with isobaric levobupivacaine, spread faster to T10 level (2.8 ± 1.1 versus 6.6 ± 4.7 minutes, P = 0.039), reached higher sensory block levels at 5 and 15 minutes after injection (T8 versus L1, P = 0.011, and T4 versus T7, P = 0.027, resp.), and had a higher peak level (T4 versus T8, P = 0.040). Isobaric levobupivacaine caused a wider range of peak levels (L1 to C8) compared with hyperbaric form (T7 to T2). The level of T4 or higher reached 90% in the hyperbaric group compared with 20% in the isobaric group (P = 0.005). Our results suggest that hyperbaric levobupivacaine was more predictable for sensory block level and more effective for surgical procedures with lower abdominal approach. Hyperbaric levobupivacaine seems to be suitable, but the optimal dosage needs further investigation. PMID:22619612

Adjunctive hyperbaric oxygen therapy in severe burns: Experience in Taiwan Formosa Water Park dust explosion disaster.

PubMed

Chiang, I-Han; Chen, Shyi-Gen; Huang, Kun-Lun; Chou, Yu-Ching; Dai, Niann-Tzyy; Peng, Chung-Kan

2017-06-01

Despite major advances in therapeutic strategies for the management of patients with severe burns, significant morbidity and mortality is observed. Hyperbaric oxygen therapy (HBOT) increases the supply of oxygen to burn areas. The aim of this study was to determine whether HBOT is effective in the treatment of major thermal burns. On June 27, 2015 in New Taipei, Taiwan, a mass casualty disaster occurred as fire erupted over a large crowd, injuring 499 people. Fifty-three victims (20 women and 33 men) were admitted to Tri-Service General Hospital. Thirty-eight patients underwent adjunctive HBOT (HBOT group), and 15 patients received routine burn therapy (control group). Serum procalcitonin (PCT) level, a sepsis biomarker, was measured until it reached normal levels (<0.5μg/L). The records of all patients from June 2015 to March 2016 were analyzed retrospectively. Outcome measures that were compared between the groups included the use of tracheostomy and hemodialysis, total body surface area (TBSA) and the number of skin graft operations, length of hospital stay, infection status, and mortality. The mean age of the patients was 22.4 years, and the mean TBSA was 43%. All the patients survived and were discharged without requiring limb amputation or being permanently disabled. Patient characteristics did not differ significantly between the groups. PCT levels returned to normal significantly faster (p=0.007) in the HBOT group. Multidisciplinary burn care combined with adjunctive HBOT improves sepsis control compared with standard treatment without HBOT. Prospective studies are required to define the role of HBOT in extensive burns. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Type II decompression sickness in a hyperbaric inside attendant.

PubMed

Johnson-Arbor, Kelly

2012-01-01

Decompression sickness (DCS) of an inside attendant (IA) is rarely encountered in hyperbarics. This report describes an IA who developed Type II DCS after a routine hyperbaric exposure. A 50-year-old male complained of lower extremity weakness and paresthesias after serving as an IA during a hyperbaric treatment to 40 fsw (122.52 kPa). Within 10 minutes after the conclusion of the treatment, the IA experienced irritability and confusion, and was unable to walk. Physical examination revealed decreased sensation below the T7 level, and decreased strength in the lower extremities. Type II DCS was diagnosed, and the IA was recompressed to 60 fsw (183.78 kPa) on a U.S. Navy Treatment Table 6, which resulted in improvement of his symptoms. Transthoracic echocardiography with bubble study performed 16 months after the event demonstrated a large patent foramen ovale (PFO). Increased age, decreased physical fitness and the undiagnosed PFO may have predisposed this attendant to developing DCS. Although rare, DCS may occur in IAs. Routine monitoring and reporting of the long-term health of hyperbaric IAs should be considered by hyperbaric facilities and medical directors in order to further understand the characteristics of DCS and other hyperbaric-related conditions in these workers.

350 años de la medicina hiperbárica: aspectos históricos, fisiopatogénicos y terapéuticos.

PubMed

Huchim, Oswaldo; Rivas-Sosa, Fernando; Rivera-Canul, Normando; Méndez-Domínguez, Nina

2017-01-01

The early use of hyperbaric therapy started with the quest to relieve respiratory problems among inhabitants of large cities during the industrial revolution, and from this, we have explored the benefits of treatment with hyperbaric oxygen in different areas of medicine. With the advances of the medical sciences, our knowledge concerning the therapies with hyperbaric oxygenation certainly has broadened and hyperbaric medicine still intrigues the contemporary medical researchers that are in seek of improve the quality of life of their patients. Copyright: © 2017 SecretarÍa de Salud.

Oxygen and Early Animal Evolution

NASA Astrophysics Data System (ADS)

Xiao, S.

2012-12-01

It is often hypothesized that the rise of animals was triggered by an increase in O2 levels in the atmosphere and oceans. However, this hypothesis is remarkably difficult to test, because the timing of animal divergences is poorly resolved, the physiology of early animals is often unknown, estimates of past pO2 levels come with large error bars, and causal relationships between oxygenation and animal evolution are difficult to establish. Nonetheless, existing phylogenetic, paleontological, and geochemical data indicate that the evolution of macroscopic animals and motile macrometazoans with energetically expensive lifestyles may be temporally coupled with ocean oxygenation events in the Ediacaran Period. Thus, it is plausible that ocean oxygenation may have been a limiting factor in the early evolution of macroscopic, complex, and metabolically aggressive animals (particularly bilaterian animals). However, ocean oxygenation and animal evolution were likely engaged in two-way interactions: Ediacaran oxygenation may have initially lifted a physiological barrier for the evolution of animal size, motility, and active lifestyles, but subsequent animal diversification in the Paleozoic may have also changed oceanic redox structures. Viewed in a broader context, the early evolutionary history of animals was contingent upon a series of events, including genetic preparation (developmental genetics), environmental facilitation (oceanic oxygenation), and ecological escalation (Cambrian explosion), but the rise of animals to ecological importance also had important geobiological impacts on oceanic redox structures, sedimentary fabrics, and global geochemical cycles.

Human circulatory responses to prolonged hyperbaric hyperoxia in Predictive Studies V

NASA Technical Reports Server (NTRS)

Pisarello, J. B.; Clark, J. M.; Lambertsen, C. J.; Gelfand, R.

1987-01-01

Selected results of cardiocirculatory measurements in healthy volunteers who breathed 100 percent O2 continuously at 3.0 ATA for up to 3.5 hr, at 2.5 ATA for up to 6.0 hr, at 2.0 ATA for up to 11.9 hr, and at 1.5 ATA for up to 19.0 hr are reported. The results indicate that resting hemodynamic responses to prolonged hyperbaric oxygen breathing in man usually consist of small deviations from normal sea-level responses. Rapid onset of bradycardia occurred at all four oxygen pressures investigated. This effect was accompanied by a rate-dependent reduction in cardiac output and a degree of systematic vasoconstriction which were small in magnitude and appeared to be functionally unimportant.

Blood lactate changes in professional Indian divers under hyperbaric conditions

PubMed Central

Sikri, Gaurav; Singh, S.P.; Srinivasa, A.B.; Chaudhry, H.B.S.

2016-01-01

Background Hyperoxia due to hyperbaric conditions influences lactate metabolism. Previous studies on lactate levels in hyperbaric conditions have reported varied results depending on the depth of evaluation and breathing gas mixture used. Methods This study compared post-exercise blood lactate levels of Indian professional male divers (breathing ambient air under normobaric conditions) with their post-exercise blood lactate levels measured under simulated hyperbaric conditions. Result In the present study, blood lactate levels in divers were found to have decreased significantly during recovery phase of exercise in hyperbaric conditions of dry diving at 2.8 Atmospheres Absolute (ATA) as compared to normobaric conditions. A significant improvement was observed in physical performance in terms of HR max and duration of exercise. Conclusion This study revealed that hyperoxia due to moderate hyperbaric condition leads to improvement in lactate metabolism in muscles and organs (liver and heart) for its removal. PMID:26900221

Research report: the effects of hyperbaric oxygen preconditioning on myocardial biomarkers of cardioprotection in patients having coronary artery bypass graft surgery.

PubMed

Jeysen, Zivan Yogaratnam; Gerard, Laden; Levant, Guvendik; Cowen, Mike; Cale, Alex; Griffin, Steve

2011-01-01

We have previously conducted and reported on the primary endpoint of a clinical study which demonstrated that hyperbaric oxygen (HBO2) preconditioning consisting of two 30-minute intervals of 100% oxygen at 2.4 atmospheres absolute (ATA) prior to coronary artery bypass graft (CABG) surgery leads to an improvement in left ventricular stroke work (LVSW) 24 hours following CABG. In that study, 81 patients were randomized to treatment with HBO2 (HBO2; n = 41) or routine treatment (Control Group; n = 40) prior to surgery. The objective of this manuscript is to further report on the result of the exploratory secondary endpoints from that study, specifically the effects of HBO2 preconditioning on biomarkers of myocardial protection. Intraoperative right atrial biopsies were assessed, via an Enzyme Linked ImmunoSorbent Assay (ELISA), for the expression of eNOS and HSP72. In this study, no significant differences were observed between the groups with respect to the quantity of myocardial eNOS and HSP72. However, in the HBO2 Group, following ischemia and reperfusion, the quantities of myocardial eNOS and HSP72 were increased. This suggests that HBO2 preconditioning in this group of patients may be capable of inducing endogenous cardioprotection following ischemic reperfusion injury (IRI).

Use of hyperbaric oxygen therapy and PEGylated carboxyhemoglobin bovine in a Jehovah's Witness with life-threatening anemia following postpartum hemorrhage.

PubMed

Thenuwara, K; Thomas, J; Ibsen, M; Ituk, U; Choi, K; Nickel, E; Goodheart, M J

2017-02-01

We present a case of a Jehovah's Witness patient who refused blood products, with the exception of albumin and clotting factors, and underwent cesarean section under spinal anesthesia complicated by postpartum hemorrhage. She was fluid resuscitated and treated with multiple uterotonics and internal iliac artery embolization. Because of agitation she required emergency tracheal intubation. Her hemoglobin concentration dropped from a preoperative value of 12mg/dL to 3mg/dL on postoperative day one. She was acidotic, requiring vasopressors for hemodynamic stability and remained ventilated and sedated. She was treated with daily erythropoietin, iron therapy and cyanocobalamin. Because of ongoing hemorrhage, continued acidemia and vasopressor requirements she was co-treated with PEGylated carboxyhemoglobin bovine and hyperbaric oxygen therapy to reverse her oxygen debt. On postoperative day eight her hemoglobin concentration was 7mg/dL, she was hemodynamically stable and vasopressors were discontinued. She was extubated and discharged from the intensive care unit on postoperative day eight. This report highlights the multiple modalities used in treating a severely anemic patient who refused blood, the use of an investigational new drug, the process of obtaining this drug via the United States Food and Drug Administration emergency expanded access regulation for single patient clinical treatment, and ethical dilemmas faced during treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of antioxidants and hyperbaric oxygen in ameliorating experimental doxorubicin skin toxicity in the rat.

PubMed

Upton, P G; Yamaguchi, K T; Myers, S; Kidwell, T P; Anderson, R J

1986-04-01

Doxorubicin, an antineoplastic drug, can cause severe ulceration if extravasated when iv injected. In this study, the effects of hyperbaric oxygenation (HBO) and the antioxidants butylated hydroxytoluene (BHT) and beta-carotene were tested on such ulcers using female Sprague-Dawley rats. It was found that HBO and vitamin A did not greatly ameliorate the ulcers produced by doxorubicin, but BHT prefed for 1 week before doxorubicin was injected was able to significantly reduce lesion size (P less than 0.05). Doxorubicin with HBO was a lethal combination, with an 87% mortality among the animals by the fourth week after injection. This was probably due to doxorubicin and HBO both promoting the formation of free radicals which are highly destructive to cells. BHT, when prefed (and to a lesser extent, beta-carotene), demonstrated a protective effect by lowering the death rate (P less than 0.05), probably due to their ability to scavenge free radicals. This experiment also tested more conventionally recommended treatments such as sodium bicarbonate (NaHCO3), hydrocortisone, and ice. NaHCO3 and hydrocortisone decreased lesion size although only at a significance of P less than 0.10. Ice did not aid in the healing of the doxorubicin-induced ulcers and even proved deleterious. Multiple injections of hydrocortisone or NaHCO3 appeared to deepen ulceration. Of all the treatments tested, free radical scavengers appear to most significantly reduce skin toxicity of doxorubicin.

Carboxyhemoglobin half-life during hyperbaric oxygen in a patient with lung dysfunction: a case report.

PubMed

Weaver, Lindell K; Deru, Kayla

2017-01-01

The carboxyhemoglobin half-life (COHb t1/2) during hyperbaric oxygen (HBO₂) is often quoted as 23 minutes, derived from the average of two adult male volunteers breathing HBO₂ at 3 atmospheres absolute (ATA). However, the mean COHb t1/2 of 12 male volunteer smokers was 26.3 minutes at 1.58 ATA and in 12 non-intubated carbon monoxide (CO) poisoned patients treated at 3 ATA, was 43 minutes. An 81-year old male, poisoned by an improperly ventilated natural gas heater, was intubated for coma, then treated with HBO₂. His PaO₂/FiO₂ = 283 from aspiration. His initial COHb was 34.4%, and 18 minutes before HBO₂, 5.9%. After a compression interval of 17 minutes, the COHb measured after 22 minutes at 3 ATA was 3.3%. By exponential decay, his COHb t1/2 before HBO₂ was 95 minutes. We estimate the range for COHb t1/2 during compression as 62-81 minutes and for the 3-ATA interval, 58 to 49 minutes, respectively. The mid-point estimate of COHb t1/2 at 3 ATA was 53 minutes. The COHb t1/2 we calculated is greater than previously reported, but longer in our patient possibly because of concomitant respiratory failure, lung dysfunction, and mechanical ventilation. The often-cited COHb t1/2 of 23 minutes, likely underestimates the actual COHb t1/2 in CO-poisoned patients, especially those with cardiopulmonary dysfunction.

Hyperbaric versus plain bupivacaine for spinal anesthesia for cesarean delivery.

PubMed

Heng Sia, Alex Tiong; Tan, Kok Hian; Sng, Ban Leong; Lim, Yvonne; Chan, Edwin S Y; Siddiqui, Fahad Javaid

2015-01-01

Bupivacaine is an amide local anesthetic used in hyperbaric and plain forms administered as spinal anesthesia for cesarean delivery. In this systematic review, we summarized the effectiveness and safety of hyperbaric versus plain bupivacaine in providing anesthesia for cesarean delivery. We considered the adequacy of anesthesia for completion of cesarean delivery and the need for interventions to treat complications. We searched the CENTRAL, MEDLINE, and EMBASE databases. We imposed no language restriction. We included all randomized controlled trials involving patients undergoing spinal anesthesia for elective cesarean delivery that compared the use of hyperbaric bupivacaine with plain bupivacaine. We included 6 studies with a total of 394 patients in this review. These studies have small sample size, few observed events, differences in methodology, and insufficient information pertaining to assessment of risk of bias. This prevented us from calculating pooled estimates. Results show that there is no compelling evidence in favor of the use of intrathecal plain or hyperbaric bupivacaine for spinal anesthesia for cesarean delivery. There is a lack of clear evidence regarding the superiority of hyperbaric compared with plain bupivacaine for spinal anesthesia for cesarean delivery. The need for conversion to general anesthesia because of failed spinal anesthesia is an important clinical outcome, but current data are insufficient to compare spinal anesthesia induced with hyperbaric compared with plain bupivacaine for this outcome. Further research is required.

Modeling Approach for Oxygen Exchange in the Human Lung under Hypobaric Conditions

DTIC Science & Technology

2001-06-01

Operational Medical Issues in Hypo-and Hyperbaric Conditions [les Questions medicales a caractere oprationel liees aux conditions hypobares ou hyperbares ] To...under Hypobaric Conditions DISTRIBUTION: Approved for public release, distribution unlimited This paper is part of the following report: TITLE...Approach for Oxygen Exchange in the Human Lung under Hypobaric Conditions Ing J.P.F. Lindhout*, Drs M. van de Graaff*, Ir Drs R.C. van de Graaff*, Dr

Hyperbaric Oxygen as Radiation Sensitizer for Locally Advanced Squamous Cell Carcinoma of the Oropharynx: A Phase 1 Dose-Escalation Study.

PubMed

Hartford, Alan C; Davis, Thomas H; Buckey, Jay C; Foote, Robert L; Sinesi, Mark S; Williams, Benjamin B; Fariss, Anna K; Schaner, Philip E; Claus, Paul L; Okuno, Scott H; Hussey, James R; Clarke, Richard E

2017-03-01

To explore, in a dose-escalation study, the feasibility of hyperbaric oxygen (HBO) treatments immediately before intensity modulated radiation therapy in conjunction with cisplatinum chemotherapy for squamous cell carcinoma of the head and neck (SCCHN). Eligible patients presented with SCCHN (stage III-IV [M0]), life expectancy >6 months, and Karnofsky performance status ≥70. Enrollees received intensity modulated radiation therapy, 70 Gy in 35 fractions over 7 weeks with weekly cisplatinum. Patients received HBO-100% oxygen, 2.4 atmospheres absolute (ATA) for 30 minutes-twice per week initially. Subsequent patients were escalated to 3 and then 5 times per week. Intensity modulated radiation therapy began within 15 minutes after HBO. Patients were followed for 2 years after RT with quality-of-life questionnaires (Performance Status Scale-Head and Neck Cancer and the Functional Assessment of Cancer Therapy-Head and Neck Cancer) and for 5+ years for local recurrence, distant metastases, disease-specific survival, and overall survival. Twelve subjects enrolled from 3 centers. Two withdrew during radiation therapy and 1 within 14 weeks after radiation therapy. The remaining 9 had primary oropharyngeal disease and were stage IVA (7) or IVB (2). No dose-limiting toxicities were observed with daily HBO. Two patients (22%) required pressure equalization tubes. The average time between HBO and radiation therapy was 8.5 minutes, with 2 of 231 administrations delivered beyond 15 minutes (0.5%). Per-protocol analysis showed a clinical complete response in 7 and a pathologic complete response without tumor in salvage neck dissections in 2. With minimum follow-up of 61 months, per-protocol 5-year overall survival was 100%, local recurrence 0%, and distant metastases 11%. Patient-reported outcomes for quality of life (Functional Assessment of Cancer Therapy-Head and Neck Cancer) were comparable to published results for chemoradiotherapy without HBO. While

Hyperbaric oxygen therapy augments the photodynamic action of methylene blue against bacteria in vitro

NASA Astrophysics Data System (ADS)

Bisland, S. K.; Dadani, F. N.; Chien, C.; Wilson, B. C.

2007-02-01

Photodynamic therapy (PDT) entails the combination of photosensitizer and light to generate cytotoxic molecules that derive from molecular oxygen (O II). The presence of sufficient O II within the target tissues is critical to the efficiency of PDT. This study investigates the use of hyperbaric oxygen therapy in combination with PDT (HOTPDT) to augment the photodynamic action of methylene blue (MB) or 5-aminolevulinic acid (ALA) against gram positive and gram negative bacterial strains in vitro. Staphylococcus aureus or Pseudomonas aeruginosa were grown in trypticase soy broth as planktonic cultures (~10 8/mL) or as established biofilms in 48 well plates (3 days old) at 32°C. Dark toxicity and PDT response in the presence or absence of HOT (2 atmospheres, 100% O II for 30, 60 or 120 min) was established for both MB (0-0.1 mM) and ALA (0- 1 mM) for a range of incubation times. The number of surviving colonies (CFU/mL) was plotted for each treatment groups. Light treatments (5, 10, 20 or 30 J/cm2) were conducted using an array of halogen bulbs with a red filter providing 90% transmittance over 600-800 nm at 21 mW/cm2. HOT increased the dark toxicity of MB (30 min, 0.1 mM) from < 0.2 log cell kill to 0.5 log cell kill. Dark toxicity of ALA (4 hr, 1 mM) was negligible and did not increase with HOT. For non-dark toxic concentrations of MB or ALA, (0.05 mM and 1 mM respectively) HOT-PDT enhanced the antimicrobial effect of MB against Staphylococcus aureus in culture by >1 and >2 logs of cell kill (CFU/mL) at 5 and 10 J/cm2 light dose respectively as compared to PDT alone. HOT-PDT also increased the anti-microbial effects of MB against Staphylococcus aureus biofilms compared to PDT, albeit less so (> 2 logs) following 10 J/cm2 light dose. Anti-microbial effects of PDT using ALA were not significant for either strain with or without HOT. These data suggest that HOTPDT may be useful for improving the PDT treatment of bacterial infections.

The effect of hyperbaric conditions on olfactory functions.

PubMed

Ay, Hakan; Salihoglu, Murat; Altundag, Aytug; Tekeli, Hakan; Memis, Ali; Cayonu, Melih

2014-01-01

The aim of this study was to investigate the effect of increased atmospheric pressure (AP) on olfactory function. The present study included 40 healthy volunteers with no history of chronic rhinosinusitis and nasal polyposis. The experimental procedure consisted of two episodes: (a) baseline episode, with normal AP; 1 absolute atmosphere (atm abs) in a test room at sea level; (b) experimental episode, increased level of AP; 2.4 atm abs in the hyperbaric chamber. Sino-nasal outcome test-20, Trail Making Test A and olfactory testing were performed in each episodes. The study group consisted of 23 men (57.5%) and 17 women (42.5%); the mean age of the study population was 38.7 +/- 9 years (range 23-58 years). The current investigation produced two major findings: (1) the mean of odor threshold scores was significantly increased in the hyperbaric condition when compared to the normobaric condition; (2) rather, there was no significant change in odor discrimination and identification scores in the hyperbaric condition. Based on two measurements taken at two different barometric pressures and the same temperature and relative humidity, this study suggests that odor threshold scores increase under hyperbaric conditions.

Hyperbaric Oxygen Therapy Can Improve Post Concussion Syndrome Years after Mild Traumatic Brain Injury - Randomized Prospective Trial

PubMed Central

Fishlev, Gregori; Bechor, Yair; Volkov, Olga; Bergan, Jacob; Friedman, Mony; Hoofien, Dan; Shlamkovitch, Nathan; Ben-Jacob, Eshel; Efrati, Shai

2013-01-01

Background Traumatic brain injury (TBI) is the leading cause of death and disability in the US. Approximately 70-90% of the TBI cases are classified as mild, and up to 25% of them will not recover and suffer chronic neurocognitive impairments. The main pathology in these cases involves diffuse brain injuries, which are hard to detect by anatomical imaging yet noticeable in metabolic imaging. The current study tested the effectiveness of Hyperbaric Oxygen Therapy (HBOT) in improving brain function and quality of life in mTBI patients suffering chronic neurocognitive impairments. Methods and Findings The trial population included 56 mTBI patients 1–5 years after injury with prolonged post-concussion syndrome (PCS). The HBOT effect was evaluated by means of prospective, randomized, crossover controlled trial: the patients were randomly assigned to treated or crossover groups. Patients in the treated group were evaluated at baseline and following 40 HBOT sessions; patients in the crossover group were evaluated three times: at baseline, following a 2-month control period of no treatment, and following subsequent 2-months of 40 HBOT sessions. The HBOT protocol included 40 treatment sessions (5 days/week), 60 minutes each, with 100% oxygen at 1.5 ATA. “Mindstreams” was used for cognitive evaluations, quality of life (QOL) was evaluated by the EQ-5D, and changes in brain activity were assessed by SPECT imaging. Significant improvements were demonstrated in cognitive function and QOL in both groups following HBOT but no significant improvement was observed following the control period. SPECT imaging revealed elevated brain activity in good agreement with the cognitive improvements. Conclusions HBOT can induce neuroplasticity leading to repair of chronically impaired brain functions and improved quality of life in mTBI patients with prolonged PCS at late chronic stage. Trial Registration ClinicalTrials.gov NCT00715052 PMID:24260334

Hyperbaric oxygen therapy can improve post concussion syndrome years after mild traumatic brain injury - randomized prospective trial.

PubMed

Boussi-Gross, Rahav; Golan, Haim; Fishlev, Gregori; Bechor, Yair; Volkov, Olga; Bergan, Jacob; Friedman, Mony; Hoofien, Dan; Shlamkovitch, Nathan; Ben-Jacob, Eshel; Efrati, Shai

2013-01-01

Traumatic brain injury (TBI) is the leading cause of death and disability in the US. Approximately 70-90% of the TBI cases are classified as mild, and up to 25% of them will not recover and suffer chronic neurocognitive impairments. The main pathology in these cases involves diffuse brain injuries, which are hard to detect by anatomical imaging yet noticeable in metabolic imaging. The current study tested the effectiveness of Hyperbaric Oxygen Therapy (HBOT) in improving brain function and quality of life in mTBI patients suffering chronic neurocognitive impairments. The trial population included 56 mTBI patients 1-5 years after injury with prolonged post-concussion syndrome (PCS). The HBOT effect was evaluated by means of prospective, randomized, crossover controlled trial: the patients were randomly assigned to treated or crossover groups. Patients in the treated group were evaluated at baseline and following 40 HBOT sessions; patients in the crossover group were evaluated three times: at baseline, following a 2-month control period of no treatment, and following subsequent 2-months of 40 HBOT sessions. The HBOT protocol included 40 treatment sessions (5 days/week), 60 minutes each, with 100% oxygen at 1.5 ATA. "Mindstreams" was used for cognitive evaluations, quality of life (QOL) was evaluated by the EQ-5D, and changes in brain activity were assessed by SPECT imaging. Significant improvements were demonstrated in cognitive function and QOL in both groups following HBOT but no significant improvement was observed following the control period. SPECT imaging revealed elevated brain activity in good agreement with the cognitive improvements. HBOT can induce neuroplasticity leading to repair of chronically impaired brain functions and improved quality of life in mTBI patients with prolonged PCS at late chronic stage. ClinicalTrials.gov NCT00715052.

Hyperbaric oxygen therapy as a potential treatment for post-traumatic stress disorder associated with traumatic brain injury

PubMed Central

Eve, David J; Steele, Martin R; Sanberg, Paul R; Borlongan, Cesar V

2016-01-01

Traumatic brain injury (TBI) describes the presence of physical damage to the brain as a consequence of an insult and frequently possesses psychological and neurological symptoms depending on the severity of the injury. The recent increased military presence of US troops in Iraq and Afghanistan has coincided with greater use of improvised exploding devices, resulting in many returning soldiers suffering from some degree of TBI. A biphasic response is observed which is first directly injury-related, and second due to hypoxia, increased oxidative stress, and inflammation. A proportion of the returning soldiers also suffer from post-traumatic stress disorder (PTSD), and in some cases, this may be a consequence of TBI. Effective treatments are still being identified, and a possible therapeutic candidate is hyperbaric oxygen therapy (HBOT). Some clinical trials have been performed which suggest benefits with regard to survival and disease severity of TBI and/or PTSD, while several other studies do not see any improvement compared to a possibly poorly controlled sham. HBOT has been shown to reduce apoptosis, upregulate growth factors, promote antioxidant levels, and inhibit inflammatory cytokines in animal models, and hence, it is likely that HBOT could be advantageous in treating at least the secondary phase of TBI and PTSD. There is some evidence of a putative prophylactic or preconditioning benefit of HBOT exposure in animal models of brain injury, and the optimal time frame for treatment is yet to be determined. HBOT has potential side effects such as acute cerebral toxicity and more reactive oxygen species with long-term use, and therefore, optimizing exposure duration to maximize the reward and decrease the detrimental effects of HBOT is necessary. This review provides a summary of the current understanding of HBOT as well as suggests future directions including prophylactic use and chronic treatment. PMID:27799776

Pulmonary decompression sickness at altitude: early symptoms and circulating gas emboli

NASA Technical Reports Server (NTRS)

Balldin, Ulf I.; Pilmanis, Andrew A.; Webb, James T.

2002-01-01

INTRODUCTION: Pulmonary altitude decompression sickness (DCS) is a rare condition. 'Chokes' which are characterized by the triad of substernal pain, cough, and dyspnea, are considered to be associated with severe accumulation of gas bubbles in the pulmonary capillaries and may rapidly develop into a life-threatening medical emergency. This study was aimed at characterizing early symptomatology and the appearance of venous gas emboli (VGE). METHODS: Symptoms of simulated-altitude DCS and VGE (with echo-imaging ultrasound) were analyzed in 468 subjects who participated in 22 high altitude hypobaric chamber research protocols from 1983 to 2001 at Brooks Air Force Base, TX. RESULTS: Of 2525 subject-exposures to simulated altitude, 1030 (41%) had symptoms of DCS. Only 29 of those included DCS-related pulmonary symptoms. Of these, only 3 subjects had all three pulmonary symptoms of chokes; 9 subjects had two of the pulmonary symptoms; and 17 subjects had only one. Of the 29 subject-exposures with pulmonary symptoms, 27 had VGE and 21 had severe VGE. The mean onset times of VGE and symptoms in the 29 subject-exposures were 42 +/- 30 min and 109 +/- 61 min, respectively. In 15 subjects, the symptoms disappeared during recompression to ground level followed by 2 h of oxygen breathing. In the remaining 14 cases, the symptoms disappeared with immediate hyperbaric oxygen treatment. CONCLUSIONS: Pulmonary altitude DCS or chokes is confirmed to be a rare condition. Our data showed that when diagnosed early, recompression to ground level pressure and/or hyperbaric oxygen treatment was 100% successful in resolving the symptoms.

Effect of combined therapy with ephedrine and hyperbaric oxygen on neonatal hypoxic-ischemic brain injury.

PubMed

Chen, Siyuan; Xiao, Nong; Zhang, Xiaoping

2009-11-13

Perinatal hypoxic-ischemic (HI) is a major cause of brain injury in the newborn, and there is a lack of effective therapies to reduce injury-related disorders. The aim of the present study was to evaluate the effect of a combination of ephedrine and hyperbaric oxygen (HBO) on neonatal hypoxic-ischemic brain injury. 7-day-old Sprague-Dawley rat pups were randomly divided into sham operation, HI, ephedrine, HBO, and combined group. The ephedrine group was intraperitoneally injected with ephedrine, HBO group was treated for 2h at 2.5 absolute atmosphere (ATA) per day, the combined group received both ephedrine and HBO treatments, the sham operation and HI groups were intraperitoneally injected with normal saline. Rat brains at 7 days after HI, were collected to determine histopathological damage and the expression levels of Caspase-3 and Nogo-A. Four weeks after insult, animals were challenged with Morris water maze test. The expressions of Caspase-3 and Nogo-A were reduced in treating groups compared to those in HI group (P<0.01). Compared with the single treatment groups, the expression levels of Caspase-3 and Nogo-A were significantly reduced in the combined group (P<0.01). Compared with the single treatment groups, the average time of escape latency was significantly shorter (P<0.01) and the number of platform location crossing was more (P<0.05) in combined group. These findings indicate that the combination of ephedrine and HBO can enhance the neuroprotective effect in the neonatal rat HI model partially mediated by inhibiting Caspase-3 and Nogo-A pathways.

Compromised breast flap treated with leech therapy, hyperbaric oxygen, pentoxifylline and topical nitroglycerin: A case report.

PubMed

Moffat, Andrew D; Weaver, Lindell K; Tettelbach, William H

2015-01-01

Hyperbaric oxygen (HBO2) is often indicated in compromised surgical flaps. Although limited to animal models and human case reports, the utilization of leech therapy (Hirudo medicinalis) with HBO2 provides better outcomes than each modality alone. Topical nitroglycerin and pentoxifylline are also frequently used adjunctively for compromised flaps. We present a case of successful breast flap salvage utilizing a combination of leech therapy, HBO2, topical nitroglycerin and pentoxifylline. A 34-year-old female, one day post-status cosmetic breast reduction mammoplasty developed a dusky discoloration of the left nipple areolar complex, indicating imminent flap failure. The patient was immediately treated with topical nitroglycerin, oral pentoxifylline, and referred for HBO2. After her first HBO2 treatment, there was clinical improvement to the superior portion of the areolar flap, with little improvement inferiorly where the discoloration had remained essentially unchanged. To address this, we added leech therapy and discontinued the topical nitroglycerin. Ceftriaxone for Aeromonas prophylaxis was started, and leeches were attached two at a time and removed from the area once feeding had ceased. These were applied three times per day for three days while receiving HBO2 twice per day for six days. The patient's flap improved and completely healed by Week 8 without need for further surgery. This is the first case to our knowledge of successful breast flap salvage using a combination of leech therapy, HBO2, topical nitroglycerin and pentoxifylline.

Hyperbaric oxygen can induce neuroplasticity and improve cognitive functions of patients suffering from anoxic brain damage

PubMed Central

Hadanny, A.; Golan, H.; Fishlev, G.; Bechor, Y.; Volkov, O.; Suzin, G.; Ben-Jacob, E.; Efrati, S.

2015-01-01

Abstract Purpose: Cognitive impairment may occur in 42–50% of cardiac arrest survivors. Hyperbaric oxygen therapy (HBO2) has recently been shown to have neurotherapeutic effects in patients suffering from chronic cognitive impairments (CCI) consequent to stroke and mild traumatic brain injury. The objective of this study was to assess the neurotherapeutic effect of HBO2 in patients suffering from CCI due to cardiac arrest. Methods: Retrospective analysis of patients with CCI caused by cardiac arrest, treated with 60 daily sessions of HBO2. Evaluation included objective computerized cognitive tests (NeuroTrax), Activity of Daily Living (ADL) and Quality of life questionnaires. The results of these tests were compared with changes in brain activity as assessed by single photon emission computed tomography (SPECT) brain imaging. Results: The study included 11 cases of CCI patients. Patients were treated with HBO2, 0.5–7.5 years (mean 2.6 ± 0.6 years) after the cardiac arrest. HBO2 was found to induce modest, but statistically significant improvement in memory, attention and executive function (mean scores) of 12% , 20% and 24% respectively. The clinical improvements were found to be well correlated with increased brain activity in relevant brain areas as assessed by computerized analysis of the SPECT imaging. Conclusions: Although further research is needed, the results demonstrate the beneficial effects of HBO2 on CCI in patients after cardiac arrest, even months to years after the acute event. PMID:26409406

Peripheral neuropathy may increase the risk for asymptomatic otic barotrauma during hyperbaric oxygen therapy: research report.

PubMed

Mozdzanowski, Christopher; Perdrizet, George A

2014-01-01

Otic barotrauma (OBT) is an adverse event seen in patients receiving hyperbaric oxygen (HBO2) therapy. After encountering a case of painless tympanic perforation during HBO2 therapy of a diabetic patient with the diagnosis of neuropathic Wagner Grade III foot ulcer, we hypothesized that peripheral neuropathy of the lower extremity may be associated with an increased risk of asymptomatic OBT during HBO2 therapy. The medical records of all HBO2 patients during a one-year period of time were reviewed. Subjects were selected based on otoscopic documentation of OBT and divided into two groups based on the presence or absence of lower extremity peripheral neuropathy. Time to therapeutic compression, presence or absence of ear-related symptoms and modified Teed (mTeed) scores were compared between the two groups. A total of 38 patients with OBT, 18 neuropathic and 20 non-neuropathic, were identified. Asymptomatic OBT occurred more frequently in the neuropathic vs. non-neuropathic group (56% vs. 5%, p < 0.001). mTeed scores were significantly greater in the neuropathic vs. non-neuropathic group (mTeed 1, 30% vs. 61%; mTeed 2, 65% vs. 36%; mTeed 3, 4% vs. 3%; p = 0.032). Mean compression times were shorter in the neuropathic vs. non-neuropathic group (10. 5 +/- 1.8 vs. 14.4 +/- 3.3 minutes, p < 0.001). The presence of peripheral neuropathy of the lower extremity may be associated with a significantly greater incidence of asymptomatic otic barotrauma during HBO2 therapy.

Interaction of Drugs in the Hyperbaric Environment, Bethesda, Maryland, 13-14 September 1979. The Undersea Medical Workshop (21st),

DTIC Science & Technology

1980-10-01

animals breath- ing a helium-oxygen mix (P02 maintained at 0.2 ATA). Results indicated that increased pressure did not alter the analgesic effect of this...diphenhydramine (Benadryl); the effects of caffeine and dimenhydrinate (Dramamine) were dependent on individual suscepti- bility, and the analgesics produced...34Behavioral Effects of Drugs in the Hyperbaric Environment) ...... ................. ... 17 J. M. Walsh Discussion ................... 23 Chapter II

[New approaches in neurosurgery and hyperbaric medicine--the importance of preventive and industrial medicine].

PubMed

Kohshi, K; Munaka, M; Abe, H; Tosaki, T

1999-12-01

Neurosurgical patients have been mainly treated by surgical procedures over the past decades. In addition, hyperbaric oxygen (HBO) therapy in neurosurgery has been used in patients with ischemic cerebrovascular diseases, head trauma, spinal damage, postoperative brain edema and others. However, the main therapeutic methods for neurosurgical diseases have changed dramatically due to developments in radiological techniques, such as radiosurgery and intravascular surgery. With changes in therapeutic methods, HBO therapy may become a very important treatment option for neurosurgical patients. For example, HBO therapy combined with radiotherapy (UOEH regimen) and anticoagulant therapy appear to be very effective in the treatments of malignant brain tumors and ischemic cerebrovascular diseases, respectively. On the other hand, medical examinations under hyper- and hypobaric environments have not yet been fully studied in the central nervous system compared to those in the cardiopulmonary systems. Moreover, the mechanisms of cerebral lesions in decompression sickness and acute mountain sickness remain unclear. Clinical neurologic approaches are very important in these fields. Hence, clinicians and researchers skilled in both neurosurgery and hyperbaric medicine will be required for advanced treatment and preventive and industrial medicine.

Effect of anemia on tumor radiosensitivity under normo and hyperbaric conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rojas, A.; Stewart, F.A.; Smith, K.A.

1987-11-01

The effect of chronic anemia on tumor radiosensitivity in a murine tumor has been investigated. Anemia was induced by bilateral kidney irradiation given several months before tumor implantation. Anemic, anemic transfused, and normal non-anemic age-matched tumor bearing animals were irradiated with X rays (2 F/24 hr) either in air, air plus misonidazole, or under hyperbaric oxygen. The most resistant response was that of tumors grown in normal mice treated in air. Anemia produced an increase in radiosensitivity which was further enhanced by red blood cell replacement. The most sensitive overall response was seen in the anemic-transfused group treated with HBO.

Effect of hyperbaric oxygen preconditioning on peri-hemorrhagic focal edema and aquaporin-4 expression.

PubMed

Fang, Jinyong; Li, Hongling; Li, Guanglei; Wang, Lichun

2015-08-01

The aim of the present study was to investigate the effect of hyperbaric oxygen preconditioning (HBO-PC) on peri-hemorrhagic focal edema and aquaporin-4 (AQP-4) expression in an experimental intracerebral hemorrhage (ICH) rat model. Sixty-six Sprague Dawley® rats were divided into three groups: The sham-surgery group (SHG; n=6); the control group (A-ICH; n=30), in which the rats were injected with autologous blood; and the experimental HBO-PC group (P-HBO; n=30). The rats underwent brain edema and AQP-4 detection at 5 postoperative time-points (24, 48 and 72 h and 5 and 7 days). The water content in the brain tissues of the A-ICH animals was higher than that in the brain tissues of the SHG rats at each time-point (P<0.05), and the edema in the P-HBO was significantly more severe 24 and 48 h postoperatively than that at 7 days postoperatively (P<0.05). The difference between the P-HBO and A-ICH was significant at 48 and 72 h postoperatively (P<0.05). AQP-4 was expressed in the post-hemorrhagic rat brains of all groups; the SHG animals exhibited low expression, while the A-ICH animals exhibited an increased expression 24 h postoperatively. In the A-ICH, expression peaked at 48 h postoperatively and began to decrease gradually after 72 h. At the 7-day time-point, the expression level in the A-ICH was closer to but still higher than that of the SHG animals (P<0.05). The differences between the P-HBO and A-ICH animals at the postoperative 24-h, 48-h and 7-day time-points were statistically significant (P<0.05). In conclusion, HBO-PC may downregulate AQP-4 expression to reduce the intracerebral edema, thus strengthening tolerance to ICH and protecting the nerves.

A comparison of low dose hyperbaric levobupivacaine and hypobaric levobupivacaine in unilateral spinal anaesthesia.

PubMed

Kaya, M; Oztürk, I; Tuncel, G; Senel, G Ozalp; Eskiçirak, H; Kadioğullari, N

2010-11-01

The aim of this study was to compare the clinical effects and characteristics of hyperbaric and hypobaric levobupivacaine for unilateral spinal anaesthesia. Sixty patients were randomly allocated into two groups to receive either 7.5 mg (1.5 ml) hyperbaric levobupivacaine 0.5% or 7.5 mg (4 ml) hypobaric levobupivacaine 0.1875% for elective arthroscopic surgery of the knee under spinal anaesthesia. The level and duration of sensory block, intensity and duration of motor block were recorded. Unilateral sensory block was observed in 27 patients (90%) in the hyperbaric group and 24 patients (80%) in the hypobaric group in the lateral position. After 15 minutes, patients were turned to supine to redistribute the spinal block toward the non-operative side, but spinal anaesthesia was still unilateral in 18 patients (60%) in the hyperbaric group and 10 patients (33%) in the hypobaric group (P = 0.038). Time to readiness for home discharge and complete recovery of sensory block were similar in both groups. In the hyperbaric group, the motor block scores were higher on the operative side during first 10 minutes than they were in the hypobaric group (P < 0.002). Motor block regression was faster in the hyperbaric group (P = 0.01). Hyperbaric and hypobaric levobupivacaine both provided satisfactory unilateral spinal anaesthesia with good haemodynamic stability for arthroscopic surgery, but with more frequent unilateral spinal anaesthesia in the hyperbaric group.

Low-oxygen waters limited habitable space for early animals.

PubMed

Tostevin, R; Wood, R A; Shields, G A; Poulton, S W; Guilbaud, R; Bowyer, F; Penny, A M; He, T; Curtis, A; Hoffmann, K H; Clarkson, M O

2016-09-23

The oceans at the start of the Neoproterozoic Era (1,000-541 million years ago, Ma) were dominantly anoxic, but may have become progressively oxygenated, coincident with the rise of animal life. However, the control that oxygen exerted on the development of early animal ecosystems remains unclear, as previous research has focussed on the identification of fully anoxic or oxic conditions, rather than intermediate redox levels. Here we report anomalous cerium enrichments preserved in carbonate rocks across bathymetric basin transects from nine localities of the Nama Group, Namibia (∼550-541 Ma). In combination with Fe-based redox proxies, these data suggest that low-oxygen conditions occurred in a narrow zone between well-oxygenated surface waters and fully anoxic deep waters. Although abundant in well-oxygenated environments, early skeletal animals did not occupy oxygen impoverished regions of the shelf, demonstrating that oxygen availability (probably >10 μM) was a key requirement for the development of early animal-based ecosystems.

Hyperbaric gaseous cryotherapy: effects on skin temperature and systemic vasoconstriction.

PubMed

Mourot, Laurent; Cluzeau, Christian; Regnard, Jacques

2007-10-01

To compare skin-surface cooling caused by the application of an ice bag (15min) and the projection of carbon dioxide microcristals (2min) under high pressure (75 bar) and low temperature (-78 degrees C), a modality called hyperbaric gaseous cryotherapy. Randomized controlled trial with repeated measure. Laboratory experiment. Twelve healthy male subjects (mean +/- standard deviation, 22.9+/-1.8y). Ice bag and hyperbaric gaseous cryotherapy were randomly applied on the skin of the nondominant hand. Skin temperature of the cooled (dorsal and palmar sides) and contralateral (dorsal side) hands were continuously measured with thermistor surface-contact probes before, during, and after (30min) cooling. Hyperbaric gaseous cryotherapy projection induced a large decrease (P<.05) of the dorsal skin temperature of the cooled hand (from 32.5 degrees +/-0.5 degrees C to 7.3 degrees +/-0.8 degrees C) and a significant decrease of the skin temperature of the palmar side and of the contralateral hand. The skin temperature of the dorsal side of the cooled hand was decreased with an ice bag (from 32.5 degrees +/-0.6 degrees C to 13.9 degrees +/-0.7 degrees C, P<.05). However, the lowest temperature was significantly higher than during hyperbaric gaseous cryotherapy, and no significant changes in the other skin temperatures were observed. Rewarming was equal after the 2 modalities, highlighting a more rapid increase of the skin temperature after hyperbaric gaseous cryotherapy. Hyperbaric gaseous cryotherapy projection decreased the skin temperature of the cooled and contralateral hand, suggesting a systemic skin vasoconstriction response. On the other hand, the vascular responses triggered by ice pack cooling appeared limited and localized to the cooled area.

Factors associated with favorable response to hyperbaric oxygen therapy among patients presenting with iatrogenic cerebral arterial gas embolism.

PubMed

Tekle, Wondwossen G; Adkinson, Cheryl D; Chaudhry, Saqib A; Jadhav, Vikram; Hassan, Ameer E; Rodriguez, Gustavo J; Qureshi, Adnan I

2013-04-01

Iatrogenic cerebral arterial gas embolism (CAGE) is an uncommon but potentially a fatal condition. Hyperbaric oxygen (HBO2) therapy is the only definitive treatment for patients with CAGE presenting with acute neurologic deficits. We reviewed medical records and neuroimaging of consecutive CAGE patients treated with HBO2 at a state referral hyperbaric facility over a 22-year period. We analyzed the effect of demographics, source of intra-arterial gas, signs and symptoms, results of imaging studies, time between event and HBO2 treatment, and response to HBO2 treatment in 36 consecutive patients. Favorable outcome was defined by complete resolution or improvement of CAGE signs and symptoms at 24 h after HBO2 treatment. Unfavorable outcome was defined by unchanged or worsened neurologic signs and symptoms or in hospital death. A total of 26 (72%) of the 36 patients had favorable outcome. Patients with favorable outcome were younger compared to those with unfavorable outcome (mean age [years, SD] 44.7 ± 17.8 vs. 58.1 ± 24.1, p = 0.08). Cardiopulmonary symptoms were significantly more common in CAGE related to venous source of gas compared to arterial source (p = 0.024) but did not influence the rate of favorable outcomes. Adjusted multivariate analysis demonstrated that time from event to HBO2 ≤ 6 h (positively) and the presence of infarct/edema on head computerized tomography (CT)/magnetic resonance imaging (MRI) before HBO2 (negatively) were independent predictors of favorable outcome at 24 h after HBO2 treatment [odds ratio (OR) 9.08 confidence interval (CI) (1.13-72.69), p = 0.0376, and (OR) 0.034 (CI) (0.002-0.58), p = 0.0200, respectively]. Two of the 36 patients were treated with thrombolytics because of acute focal deficits and suspected ischemia-one with intravenous and the second with intra-arterial thrombolysis. The latter patient developed fatal intracerebral hemorrhage. A high proportion of CAGE patients treated with HBO2 had favorable outcomes. Time

Hyperbaric oxygen treatment for inflammatory bowel disease: a systematic review and analysis

PubMed Central

2012-01-01

Background Traditionally, hyperbaric oxygen treatment (HBOT) has been used to treat a limited repertoire of disease, including decompression sickness and healing of problem wounds. However, some investigators have used HBOT to treat inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis. Methods Comprehensive searches were conducted in 8 scientific databases through 2011 to identify publications using HBOT in IBD. Human studies and animal models were collated separately. Results Thirteen studies of HBOT in Crohn's disease and 6 studies in ulcerative colitis were identified. In all studies, participants had severe disease refractory to standard medical treatments, including corticosteroids, immunomodulators and anti-inflammatory medications. In patients with Crohn's disease, 31/40 (78%) had clinical improvements with HBOT, while all 39 patients with ulcerative colitis improved. One study in Crohn's disease reported a significant decrease in proinflammatory cytokines (IL-1, IL-6 and TNF-alpha) and one study in ulcerative colitis reported a decrease in IL-6 with HBOT. Adverse events were minimal. Twelve publications reported using HBOT in animal models of experimentally-induced IBD, including several studies reporting decreased markers of inflammation or immune dysregulation, including TNF-alpha (3 studies), IL-1beta (2 studies), neopterin (1 study) and myeloperoxidase activity (5 studies). HBOT also decreased oxidative stress markers including malondialdehyde (3 studies) and plasma carbonyl content (2 studies), except for one study that reported increased plasma carbonyl content. Several studies reported HBOT lowered nitric oxide (3 studies) and nitric oxide synthase (3 studies) and one study reported a decrease in prostaglandin E2 levels. Four animal studies reported decreased edema or colonic tissue weight with HBOT, and 8 studies reported microscopic improvements on histopathological examination. Although most publications reported

Dose-response study of spinal hyperbaric ropivacaine for cesarean section

PubMed Central

Chen, Xin-zhong; Chen, Hong; Lou, Ai-fei; Lü, Chang-cheng

2006-01-01

Background: Spinal hyperbaric ropivacaine may produce more predictable and reliable anesthesia than plain ropivacaine for cesarean section. The dose-response relation for spinal hyperbaric ropivacaine is undetermined. This double-blind, randomized, dose-response study determined the ED50 (50% effective dose) and ED95 (95% effective dose) of spinal hyperbaric ropivacaine for cesarean section anesthesia. Methods: Sixty parturients undergoing elective cesarean section delivery with use of combined spinal-epidural anesthesia were enrolled in this study. An epidural catheter was placed at the L1~L2 vertebral interspace, then lumbar puncture was performed at the L3~L4 vertebral interspace, and parturients were randomized to receive spinal hyperbaric ropivacaine in doses of 10.5 mg, 12 mg, 13.5 mg, or 15 mg in equal volumes of 3 ml. Sensory levels (pinprick) were assessed every 2.5 min until a T7 level was achieved and motor changes were assessed by modified Bromage Score. A dose was considered effective if an upper sensory level to pin prick of T7 or above was achieved and no intraoperative epidural supplement was required. ED50 and ED95 were determined with use of a logistic regression model. Results: ED50 (95% confidence interval) of spinal hyperbaric ropivacaine was determined to be 10.37 (5.23~11.59) mg and ED95 (95% confidence interval) to be 15.39 (13.81~23.59) mg. The maximum sensory block levels and the duration of motor block and the rate of hypotension, but not onset of anesthesia, were significantly related to the ropivacaine dose. Conclusion: The ED50 and ED95 of spinal hyperbaric ropivacaine for cesarean delivery under the conditions of this study were 10.37 mg and 15.39 mg, respectively. Ropivacaine is suitable for spinal anesthesia in cesarean delivery. PMID:17111469

Early Cambrian oxygen minimum zone-like conditions at Chengjiang

NASA Astrophysics Data System (ADS)

Hammarlund, Emma U.; Gaines, Robert R.; Prokopenko, Maria G.; Qi, Changshi; Hou, Xian-Guang; Canfield, Donald E.

2017-10-01

The early Cambrian succession at Chengjiang contains the most diverse Cambrian fossil assemblage yet described, and contributes significantly to our understanding of the diversification of metazoans in the Cambrian ;explosion;. The Cambrian Period occupies a transitional episode of global ocean chemistry, following the oxygenation of the surface ocean and of shallow marine environments during the Ediacaran Period, but prior to the establishment of a predominantly oxygenated deep ocean in the mid-Paleozoic. Despite recent attention, a detailed understanding of the chemical conditions that prevailed in early Cambrian marine settings and the relationship of those conditions to early metazoan ecosystems is still emerging. Here, we report multi-proxy geochemical data from two drill cores through the early Cambrian (Series 2) Yu'anshan Formation of Yunnan, China. Results reveal dynamic water-column chemistry within the succession, which progressively shifted from euxinic to oxic conditions during deposition of the Yu'anshan Formation. The Chengjiang biota occurs in strata that appear to have been deposited under an oxygen-depleted water column that may have supported denitrification, as in modern oxygen-minimum zones. The oxygenated benthic environments in which the Chengjiang biota thrived were proximal to, but sharply separated from, the open ocean by a persistent anoxic water mass that occupied a portion of the outer shelf. Oxygen depletion in the lower water column developed dynamically in response to nutrient availability and possibly at lower thresholds of productivity due to lower atmospheric oxygen concentrations in Cambrian. These findings suggest that the frequent development of oxygen-limiting conditions in continental margin settings provided an environmental barrier that may have affected biogeographic, ecological and evolutionary development of early metazoan communities.

16. NBS TOPSIDE CONTROL ROOM, THE NBS HYPERBARIC CHAMBER IS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. NBS TOPSIDE CONTROL ROOM, THE NBS HYPERBARIC CHAMBER IS VERY CLOSE TO THE WATER'S EDGE AND HERE FOR DIVER EMERGENCY SUPPORT. A MEDICAL STAFF IS LOCATED ON THE MARSHALL SPACE FLIGHT CENTER (MSFC) AND SUPPORTS THE NBS PERSONNEL WHEN HYPERBARIC CHAMBER OPERATION IS NECESSARY. - Marshall Space Flight Center, Neutral Buoyancy Simulator Facility, Rideout Road, Huntsville, Madison County, AL

Comparison of hypobaric, hyperbaric, and isobaric solutions of bupivacaine during continuous spinal anesthesia.

PubMed

Van Gessel, E F; Forster, A; Schweizer, A; Gamulin, Z

1991-06-01

This study was designed to compare the anesthetic properties of hypobaric bupivacaine with those of isobaric and hyperbaric solutions when administered in the supine position in an elderly population undergoing hip surgery using continuous spinal anesthesia. Plain bupivacaine (0.5%) was mixed with equal volumes of 10% dextrose (hyperbaric), 0.9% NaCl (isobaric), or distilled water (hypobaric) to obtain 0.25% solutions. In a double-blind fashion, all patients received 3 mL (7.5 mg) of their particular solution injected through the spinal catheter in the horizontal supine position. The sensory level obtained in the hyperbaric group (median, T4; range, T3-L3) was significantly higher than in both the isobaric (median, T11; range, T6-L1) and hypobaric (median, L1; range, T4-L3) groups. A motor blockade of grade 2 or 3 was obtained in 14 of 15 and 12 of 15 patients in, respectively, the hyperbaric and isobaric groups, but only in 8 of 15 patients in the hypobaric group. After the initial injection of 3 mL (7.5 mg), a sensory level of T10 and a motor blockade of grade 2 or 3 was obtained in 14 of 15, 5 of 15, and 3 of 15 patients in the hyperbaric, isobaric, and hypobaric groups, respectively. All remaining patients received 1 or 2 additional milliliters (2.5-5 mg) and achieved these required anesthetic conditions, except for one patient in the hyperbaric group and eight patients in the hypobaric group in whom anesthesia was achieved with hyperbaric tetracaine. The decrease in mean arterial pressure was significantly more severe in the hyperbaric (30%) than in either the isobaric (18%) or hypobaric (14%) groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Test results for the evaluation of a glucometer for use under hyperbaric conditions: Technical report.

PubMed

Tsouras, Theo

2017-01-01

This study aimed to evaluate a recently developed equipment test method by assessing the safe and accurate functioning of the Abbott Optium FreeStyle H portable blood glucose monitor for use in the Alfred Hospital's hyperbaric chamber. The results of this study indicate that the test method can be used successfully to evaluate instruments and/or devices for use in the hyperbaric environment. The evaluation initially found that this particular glucose monitor contained a lithium battery which can be hazardous when used in the hyperbaric environment. However, upon further inspection it was determined the battery posed minimal risk for fire and explosion due to its small capacity and design application. The results indicate that the Abbott Optium FreeStyle H blood glucose monitor operated normally when used in the hyperbaric chamber. This glucometer was found to perform within the calibration specification requirements for accuracy at all stages of a typical hyperbaric treatment and as such the Abbott Optium FreeStyle H blood glucose monitor was deemed safe for use in the hyperbaric chamber at the Alfred Hospital. Copyright© Undersea and Hyperbaric Medical Society.

Is Hyperbaric Oxygen Therapy Effective for Traumatic Brain Injury? A Rapid Evidence Assessment of the Literature and Recommendations for the Field.

PubMed

Crawford, Cindy; Teo, Lynn; Yang, EunMee; Isbister, Caitlin; Berry, Kevin

This systematic review examines the efficacy of hyperbaric oxygen (HBO2) for traumatic brain injury (TBI) to make evidence-based recommendations for its application and future research. A comprehensive search was conducted to identify studies through 2014. Methodological quality was assessed and synthesis and interpretation of relevant data was performed. Twelve randomized trials were included. All mild TBI studies demonstrated minimal bias and no statistically significant differences between HBO2 and sham arms. Statistically significant improvement occurred over time within both groups. Moderate-to-severe TBI studies were of mixed quality, with majority of results favoring HBO2 compared with "standard care." The placebo analysis conducted was limited by lack of details. For mild TBI, results indicate HBO2 is no better than sham treatment. Improvements within both HBO2 and sham groups cannot be ignored. For acute treatment of moderate-to-severe TBI, although methodology appears flawed across some studies, because of the complexity of brain injury, HBO2 may be beneficial as a relatively safe adjunctive therapy if feasible. Further research should be considered to resolve the controversy surrounding this field, but only if methodological flaws are avoided and bias minimized.

[Effect of 2000 m descent simulated in a hyperbaric chamber on arterial blood oxygen saturation and sleep quality in workers of a gold mine situated at an altitude of 3800-4200 m above sea level].

PubMed

Przybyłowski, Tadeusz; Ashirbaev, Aibek; Le Roux, Johannes; Zieliński, Jan

2003-01-01

Acute mountain sickness can become life threatening to people traveling at high altitude. Simulated descent with a hyperbaric chamber is a widely accepted way to treat this condition. The aim of this study was to analyze the influence of simulated descent to 2000 m on arterial oxygen saturation (SaO2), periodic breathing and sleep quality in a group of workers of a gold mine situated at 3800 m. Sleep studies were performed twice in stationary hyperbaric chamber with a portable system--MESAM IV in 20 workers. During the first study the chamber was not pressurized and on the second night the barometric pressure was set to mimic descent to 2000 m. During second study, a significant decrease in ODI (Oxygen Desaturation Index), from 9.7 +/- 6/h to 1.8 +/- 3.4/h (p < 0.0001), was noticed; mean SaO2 increased from 84.3 +/- 3.2% do 92.7 +/- 2.8% (p < 0.0001), significant changes in percentage of study time in individual SaO2 ranges were also noticed. The number (12.7 +/- 8.4 vs. 7.5 +/- 5; p < 0.05) and index of changes in body position were decreased (2.0 +/- 1.5 vs. 1.2 +/- 0.9/h; p < 0.05) as well. Simulated descent to 2000 m causes a decrease in number of desaturations, improvement in mean SaO2 during sleep, decrease in heart rate and these data suggest a decrease in periodic breathing during sleep. A decrease in number and index of body position changes suggests improved sleep quality.

The medical use of oxygen: a time for critical reappraisal.

PubMed

Sjöberg, F; Singer, M

2013-12-01

Oxygen treatment has been a cornerstone of acute medical care for numerous pathological states. Initially, this was supported by the assumed need to avoid hypoxaemia and tissue hypoxia. Most acute treatment algorithms, therefore, recommended the liberal use of a high fraction of inspired oxygen, often without first confirming the presence of a hypoxic insult. However, recent physiological research has underlined the vasoconstrictor effects of hyperoxia on normal vasculature and, consequently, the risk of significant blood flow reduction to the at-risk tissue. Positive effects may be claimed simply by relief of an assumed local tissue hypoxia, such as in acute cardiovascular disease, brain ischaemia due to, for example, stroke or shock or carbon monoxide intoxication. However, in most situations, a generalized hypoxia is not the problem and a risk of negative hyperoxaemia-induced local vasoconstriction effects may instead be the reality. In preclinical studies, many important positive anti-inflammatory effects of both normobaric and hyperbaric oxygen have been repeatedly shown, often as surrogate end-points such as increases in gluthatione levels, reduced lipid peroxidation and neutrophil activation thus modifying ischaemia-reperfusion injury and also causing anti-apoptotic effects. However, in parallel, toxic effects of oxygen are also well known, including induced mucosal inflammation, pneumonitis and retrolental fibroplasia. Examining the available 'strong' clinical evidence, such as usually claimed for randomized controlled trials, few positive studies stand up to scrutiny and a number of trials have shown no effect or even been terminated early due to worse outcomes in the oxygen treatment arm. Recently, this has led to less aggressive approaches, even to not providing any supplemental oxygen, in several acute care settings, such as resuscitation of asphyxiated newborns, during acute myocardial infarction or after stroke or cardiac arrest. The safety of more

Hyperbaric Oxygen Treatment in Radiation-Induced Cystitis and Proctitis: A Prospective Cohort Study on Patient-Perceived Quality of Recovery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oscarsson, Nicklas, E-mail: nicklas.oscarsson@vgregion.se; Arnell, Per; Lodding, Pär

Purpose: In this prospective cohort study, the effects of hyperbaric oxygen treatment (HBOT) were evaluated concerning patient-perceived symptoms of late radiation-induced cystitis and proctitis secondary to radiation therapy for pelvic cancer. Methods and Materials: Thirty-nine patients, 35 men and 4 women with a mean age of 71 (range, 35-84) years were included after informed consent and institutional ethics approval. They had all been treated with radiation therapy for prostate (n=34), cervix (n=2), or rectal (n=3) cancer using external beam radiation at a dose of 25 to 75 Gy. Patients with hematuria requiring blood transfusion were excluded. The HBOT was deliveredmore » with 100% oxygen for 90 minutes at 2.0 to 2.4 atmospheres (ATA). Mean number of treatments was 36 (28-40). Symptoms were prospectively assessed using the Expanded Prostate Index Composite score before, during, and 6 to 12 months after HBOT. Results: The HBOT was successfully conducted, and symptoms were alleviated in 76% for patients with radiation cystitis, 89% for patients with radiation proctitis, and 88% of patients with combined cystitis and proctitis. Symptom reduction was demonstrated by an increased Expanded Prostate Index Composite score in the urinary domain from 50 ± 16 to 66 ± 20 after treatment (P<.001) and in the bowel domain from 48 ± 18 to 68 ± 18 after treatment (P<.001). For 31% of the patients with cystitis and 22% with proctitis, there were only trivial symptoms after HBOT. The improvement was sustained at follow-up in both domains 6 to 12 months after HBOT. No severe side effects were observed related to HBOT, and treatment compliance was high. Conclusions: HBOT can be an effective and safe treatment modality for late radiation therapy-induced soft tissue injuries in the pelvic region.« less

Low pressure hyperbaric oxygen therapy and SPECT brain imaging in the treatment of blast-induced chronic traumatic brain injury (post-concussion syndrome) and post traumatic stress disorder: a case report

PubMed Central

2009-01-01

A 25-year-old male military veteran presented with diagnoses of post concussion syndrome and post traumatic stress disorder three years after loss of consciousness from an explosion in combat. The patient underwent single photon emission computed tomography brain blood flow imaging before and after a block of thirty-nine 1.5 atmospheres absolute hyperbaric oxygen treatments. The patient experienced a permanent marked improvement in his post-concussive symptoms, physical exam findings, and brain blood flow. In addition, he experienced a complete resolution of post-traumatic stress disorder symptoms. After treatment he became and has remained employed for eight consecutive months. This case suggests a novel treatment for the combined diagnoses of blast-induced post-concussion syndrome and post-traumatic stress disorder. PMID:19829822

Influence of hyperbaric oxygen on biomechanics and structural bone matrix in type 1 diabetes mellitus rats.

PubMed

Limirio, Pedro Henrique Justino Oliveira; da Rocha Junior, Huberth Alexandre; Morais, Richarlisson Borges de; Hiraki, Karen Renata Nakamura; Balbi, Ana Paula Coelho; Soares, Priscilla Barbosa Ferreira; Dechichi, Paula

2018-01-01

The aim of this study was to evaluate the biomechanics and structural bone matrix in diabetic rats subjected to hyperbaric oxygen therapy (HBO). Twenty-four male rats were divided into the following groups: Control; Control + HBO; Diabetic, and Diabetic + HBO. Diabetes was induced with streptozotocin (STZ) in the diabetic Groups. After 30 days, HBO was performed every 48h in HBO groups and all animals were euthanized 60 days after diabetic induction. The femur was submitted to a biomechanical (maximum strength, energy-to-failure and stiffness) and Attenuated Total Reflectance Fourier transform infrared (ATR-FTIR) analyses (crosslink ratio, crystallinity index, matrix-to-mineral ratio: Amide I + II/Hydroxyapatite (M:MI) and Amide III + Collagen/HA (M:MIII)). In biomechanical analysis, diabetic animals showed lower values of maximum strength, energy and stiffness than non-diabetic animals. However, structural strength and stiffness were increased in groups with HBO compared with non-HBO. ATR-FTIR analysis showed decreased collagen maturity in the ratio of crosslink peaks in diabetic compared with the other groups. The bone from the diabetic groups showed decreased crystallinity compared with non-diabetic groups. M:MI showed no statistical difference between groups. However, M:MIII showed an increased matrix mineral ratio in diabetic+HBO and control+HBO compared with control and diabetic groups. Correlations between mechanical and ATR-FTIR analyses showed significant positive correlation between collagen maturity and stiffness. Diabetes decreased collagen maturation and the mineral deposition process, thus reducing biomechanical properties. Moreover, the study showed that HBO improved crosslink maturation and increased maximum strength and stiffness in the femur of T1DM animals.

Polysulfone coating for hollow fiber artificial lungs operated at hypobaric and hyperbaric pressures.

PubMed

High, K M; Snider, M T; Panol, G R; Richard, R B; Gray, D N

1996-01-01

Carbon dioxide transfer is increased when the gas phase of a hollow fiber membrane lung is operated at hypobaric pressures. Oxygen transfer is augmented by hyperbaric pressures. However, uncoated hollow fibers transmit gas bubbles into the blood when operated at a pressure greater than 800 mmHg and may have increased plasma leakage when operated at hypobaric pressures. Ultrathin polymer coatings may avoid this problem while reducing thrombogenicity. The authors coated microporous polypropylene hollow fibers with 380 microns outer diameter and 50 microns walls using 1, 2, 3, and 4% solutions of polysulfone in tetrahydrofuran by dipping or continuous pull through. These fibers were mounted in small membrane lung prototypes having surface areas of 70 and 187 cm2. In gas-to-gas testing, the longer the exposure time to the solution and the greater the polymer concentration, the less the permeation rate. The 3% solutions blocked bulk gas flow. The coating was 1 micron thick by mass balance calculations. During water-to-gas tests, hypobaric gas pressures of 40 mmHg absolute were tolerated, but CO2 transfer was reduced to 40% of the bare fibers. Hyperbaric gas pressures of 2,100 mmHg absolute tripled O2 transfer without bubble formation.

Effect of intrathecal hyperbaric bupivacaine with small dose clonidine versus hyperbaric bupivacaine alone in lower abdominal surgeries: A comparative study

PubMed Central

Tyagi, Amit; Rastogi, Shivani; Tripathi, Manoj; Bhandari, Rajlaxmi; Bais, Prateek Singh; Singh, Mahendra

2016-01-01

Context: The continued success of regional anesthetic techniques can be credited due to improved local anesthetic drugs, with lower toxicities and longer duration of action, but still many efforts are being done to increase the duration of the block and postoperative analgesia. Therefore, use of adjuvant drugs for anesthesia is intended to prolong analgesia and preventing deleterious clinical effects of local anesthetics. Aims: The present study is designed to evaluate effects of intrathecal hyperbaric bupivacaine versus hyperbaric bupivacaine with low dose clonidine on the onset and level of sensory and motor block, the intensity of motor blockade, and time of analgesia required in the postoperative period. Settings and Design: Study area were our operation theater and postanesthesia care unit of Department of Anesthesiology, this was a prospective, randomized, placebo-controlled, and double-blind study for a period of 1 year comprising of 60 patients. Materials and Methods: Patients were randomly allocated into two groups: Group 1 (S) (n = 30): Patients received intrathecal hyperbaric bupivacaine 12.5 mg with normal saline 0.5 ml and Group 2 (C) (n = 30): Patients received intrathecal hyperbaric bupivacaine 12.5 mg with 1 μg/kg clonidine (approximated to 0.5 ml with normal saline). Statistical Analysis: Two groups were compared by Student's t-test, Chi-square test; ANOVA and significance of mean difference bet were done by Newman–Keuls test. Results and Conclusion: Duration of analgesia was prolonged in Group C (363.07 ± 166.30 min) patients compared to Group S patients (226.95 ± 119 min) and they also required less top up analgesic in the postoperative period. PMID:27212746

Simultaneous Monitoring of Vascular Oxygenation and Tissue Oxygen Tension of Breast Tumors Under Hyperbaric Oxygen Exposure

DTIC Science & Technology

2008-04-01

28. Alagoz, T., R. Buller, B. Anderson, K. Terrell , R...and oxygenation Ann . New Acad. Sci. 838 29–45 Chapman J D, Stobbe C C, Arnfield M R, Santus R, Lee J and McPhee M S 1991 Oxygen dependency of tumor

Reducing pulmonary injury by hyperbaric oxygen preconditioning during simulated high altitude exposure in rats.

PubMed

Li, Zhuo; Gao, Chunjin; Wang, Yanxue; Liu, Fujia; Ma, Linlin; Deng, Changlei; Niu, Ko-Chi; Lin, Mao-Tsun; Wang, Chen

2011-09-01

Hyperbaric oxygen preconditioning (HBO₂P + HAE) has been found to be beneficial in preventing the occurrence of ischemic damage to brain, spinal cord, heart, and liver in several disease models. In addition, pulmonary inflammation and edema are associated with a marked reduction in the expression levels of both aquaporin (AQP) 1 and AQP5 in the lung. Here, the aims of this study are first to ascertain whether acute lung injury can be induced by simulated high altitude in rats and second to assess whether HBO2P + HAE is able to prevent the occurrence of the proposed high altitude-induced ALI. Rats were randomly divided into the following three groups: the normobaric air (NBA; 21% O₂ at 1 ATA) group, the HBO₂P + high altitude exposure (HAE) group, and the NBA + HAE group. In HBO₂P + HAE group, animals received 100% O₂ at 2.0 ATA for 1 hour per day, for five consecutive days. In HAE groups, animals were exposed to a simulated HAE of 6,000 m in a hypobaric chamber for 24 hours. Right after being taken out to the ambient, animals were anesthetized generally and killed and thoroughly exsanguinated before their lungs were excised en bloc. The lungs were used for both histologic and molecular evaluation and analysis. In NBA + HAE group, the animals displayed higher scores of alveolar edema, neutrophil infiltration, and hemorrhage compared with those of NBA controls. In contrast, the levels of both AQP1 and AQP5 proteins and mRNA expression in the lung in the NBA + HAE group were significantly lower than those of NBA controls. However, the increased lung injury scores and the decreased levels of both AQP1 and AQP5 proteins and mRNA expression in the lung caused by HAE was significantly reduced by HBO₂P + HAE. Our results suggest that high altitude pulmonary injury may be prevented by HBO2P + HAE in rats.

Hyperbaric oxygen therapy in the treatment of osteonecrosis of the femoral head: a review of the current literature.

PubMed

Uzun, Gunalp; Mutluoglu, Mesut; Ersen, Omer; Yildiz, Senol

2016-01-01

To review the current literature on the use of hyperbaric oxygen (HBO₂) therapy in the treatment of osteonecrosis of the femoral head (ONFH). We searched PubMed, Directory of Open Access Journals (DOAJ), EMBASE, Web of Science, Academic Search Complete, CINAHL and MEDLINE through April 2015. We hand-searched relevant textbooks, conference proceedings and the reference lists of review articles and clinical studies Randomized controlled trials (RCT) and observational studies (cohort study, case-control study, case series) that reported the outcome of patients who received HBO₂therapy for ONFH were included. Only English-language articles were included. Study quality was not used as an exclusion criterion. Two authors independently assessed trials for inclusion, extracted data and presented to other authors. Disagreements were resolved by consensus. We identified eight clinical studies; two randomized controlled trials (RCTs); one historically controlled study; and five case series. The majority of the studies were small-scale, heterogeneous and methodologically weak. In four of the studies HBO₂therapy was combined with other treatment modalities, making it impossible to draw firm conclusions on the specific effects of HBO₂therapy. Hip survivorship in studies wherein HBO₂therapy was used alone was 95.5% in Steinberg Stage I lesions, 89% in Steinberg Stage II lesions and 100% in Ficat Stage II lesions. There is a room for HBO₂therapy in the management ONFH. Further RCTs, however, are required to better elucidate the role of HBO₂therapy in the treatment of ONFH.

Incidence of DCS and oxygen toxicity in chamber attendants: a 28-year experience.

PubMed

Witucki, Pete; Duchnick, Jay; Neuman, Tom; Grover, Ian

2013-01-01

Decompression sickness (DCS) and central nervous system oxygen toxicity are inherent risks for "inside" attendants (IAs) of hyperbaric chambers. At the Hyperbaric Medicine Center at the University of California San Diego (UCSD), protocols have been developed for decompressing IAs. Protocol 1: For a total bottom time (TBT) of less than 80 minutes at 2.4 atmospheres absolute (atm abs) or shallower, the U.S. Navy (1955) no-decompression tables were utilized. Protocol 2: For a TBT between 80 and 119 minutes IAs breathed oxygen for 15 minutes prior to initiation of ascent. Protocol 3: For a TBT between 120-139 minutes IAs breathed oxygen for 30 minutes prior to ascent. These protocols have been utilized for approximately 28 years and have produced zero cases of DCS and central nervous system oxygen toxicity. These results, based upon more than 24,000 exposures, have an upper limit of risk of DCS and oxygen toxicity of 0.02806 (95% CI) using UCSD IA decompression Protocol 1, 0.00021 for Protocol 2, and 0.00549 for Protocol 3. We conclude that the utilization of this methodology may be useful at other sea-level multiplace chambers.

[The effect of long-term hyperbarism on pregnant guinea pigs and their progeny].

PubMed

Sviderskaia, G E; Dmitrieva, L E

1991-01-01

The effect of hyperbarism has been investigated on 1-3-, 4-5- and 8-10-week pregnant rats and their offsprings. It was found that the mortality rate of pregnant rats is two times higher after hyperbaric exposures than in control animals. The animals exhibit the highest sensitivity at a stage of 8-10 weeks. Hyperbaric conditions significantly affect offsprings. Only 53% of newborn puppies were found to be normal, whereas 35% were born dead and 12% revealed various abnormalities. The highest sensitivity was observed during organogenesis (4-5 weeks), the mortality rate during this period reached 70%. The body mass in newborn puppies was significantly lower than in control animals. The most significant retardation in the development was observed in animals which were subjected to the effect of hyperbarism at the 4-5-th week of intrauterine life.

Topical oxygen therapy & micro/nanobubbles: a new modality for tissue oxygen delivery.

PubMed

Sayadi, Lohrasb R; Banyard, Derek A; Ziegler, Mary E; Obagi, Zaidal; Prussak, Jordyne; Klopfer, Michael J; Evans, Gregory Rd; Widgerow, Alan D

2018-06-01

Up to 15 billion dollars of US health care expenditure each year is consumed by treatment of poorly healing wounds whose etiologies are often associated with aberrancies in tissue oxygenation. To address this issue, several modes of tissue oxygen delivery systems exist, including Hyperbaric Oxygen Therapy (HBOT) and Topical Oxygen Therapy (TOT), but their efficacies have yet to be fully substantiated. Micro/nanobubbles (MNBs), which range anywhere from 100 μm to <1 μm in diameter and are relatively stable for hours, offer a new mode of oxygen delivery to wounds. The aim of this article is to systematically review literature examining the use of TOT for wound healing and use of MNBs for tissue oxygenation using the MEDLINE database. The search yielded 87 articles (12 MNB articles and 75 TOT articles), of which 52 met the inclusion criteria for this literature review (12 MNB articles and 40 TOT articles). Additionally, we present an analysis on the efficacy of our MNB generating technology and propose its use as a wound healing agent. © 2018 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Oxygen and wound care: a review of current therapeutic modalities and future direction.

PubMed

Howard, Michael A; Asmis, Reto; Evans, Karen Kim; Mustoe, Thomas A

2013-01-01

While the importance of oxygen to the wound healing process is well accepted, research and technological advances continue in this field and efforts are ongoing to further utilize oxygen as a therapeutic modality. In this paper, the authors briefly review the role of oxygen in wound healing and discuss the distinct mechanism of action as well as the advantages and disadvantages of the three major oxygen-based therapies currently in clinical use (Hyperbaric Oxygen and Topical Oxygen and Continuous Diffusion of Oxygen), as well as review the existing literature regarding these distinct therapeutic modalities. © 2013 by the Wound Healing Society.

Oxygen in wound healing: nutrient, antibiotic, signaling molecule, and therapeutic agent.

PubMed

Eisenbud, David E

2012-07-01

Disturbances to healing observed under hypoxic conditions have given insights into the roles of oxygen. Wound hypoxia is more prevalent than generally appreciated, and occurs even in patients who are free of arterial occlusive disease. There is a strong scientific basis for oxygen treatment as prophylaxis against infection, to facilitate wound closure, and to prevent amputation in wounded patients. This article reviews extensive data from preclinical and human trials of supplemental inhaled oxygen, hyperbaric oxygen, and topical oxygen treatment. Oxygen supports biochemical metabolism and cellular function, and has roles in combating infection and facilitating the wound healing cascade. Copyright © 2012 Elsevier Inc. All rights reserved.

Effect of Exposure to Hyperoxic, Hypobaric, and Hyperbaric Environments on Concentrations of Selected Aerobic and Anaerobic Fecal Flora of Mice

PubMed Central

Gillmore, James D.; Gordon, Francis B.

1975-01-01

Alterations in selected aerobic and anaerobic fecal microflora of the mouse were determined during exposure to hyperoxic and normoxic hypo- and hyperbaric environments. Examination of fecal cultures obtained during exposure for 6 weeks to either 60 or 77% oxygen concentration at 1 atmosphere absolute revealed little alteration in the aerobic or anaerobic flora. There appeared to be only a retardation in the reduction of the Klebsiella-Enterobacter flora which normally occurs after weaning. During exposure to hypobaric environments (100% O2, 0.2 atmosphere absolute), significant alterations in concentrations of Escherichia coli, slow lactose fermenters, Klebsiella-Enterobacter, and enterococci were found in some instances. All alterations were toward increased concentrations. Variations in concentrations of different colony types of obligately anaerobic gram-positive (anGPR) and gram-negative (anGNR) rods cultured during the same experiments also occurred. One colony type of anGPR appeared to decrease while a second type increased in numbers. Concentrations of three colony types of anGNR were generally, but not always, increased. During hyperbaric exposure (2.8% O2, 7.5 atmospheres absolute), increased concentrations of Klebsiella-Enterobacter, E. coli, slow lactose fermenters and enterococci were also noted. Changes in numbers of both colony types of anGPR, when occurring, were in the direction of lower numbers. Alteration in numbers of anGNR were in both directions but were more frequent in the direction of higher numbers. After return to normal air for 4 weeks of either hypo- or hyperbaric exposure, fecal concentrations of all organisms tended to revert toward control values with the exception of the anGPR which remained in lower concentrations after termination of the hyperbaric exposure. These observations indicate that, despite the great variation in the fecal flora among individual mice, it is possible to discover the effects induced by altered gaseous

A novel system for organ and tissues preservation: the refrigerating hyperbaric chamber.

PubMed

Guimarães, F A G; Taha, M O; Simões, M J; Moino, C A A; Santos, I V; Amador, J C; Santos, R A; Queiroz, R B; Amaro, R R; Jesus, M A S

2006-01-01

This study was designed to investigate the feasibility of building a simple and inexpensive device to preserve organs or tissues in hyperbaric and hypothermic conditions. The device was built on a 40-cm wide, 28-cm long, and 23-cm deep stainless steel chassis. The pressure vessel was built by a 7.8-cm bore stainless steel cylinder put inside another 12-cm cylinder welded together and closed by a steel plate on the top and bottom. The inferior plate was welded, and the superior one was fixed by manual clasp nut. The cooling system is made up of air compressor, condenser, expansion area, and cooling worm that is located between the cylinders. The temperature-controlling device is a computer processor contained in an integrated-circuit chip, with a on-off system to maintain the chamber temperature between 2 degrees to 4 degrees C. The compression of the chamber is performed by lateral coupling with the oxygen cylinder and is maintained at 5.5 absolute atmospheres and controlled by air pressure gauge. The maximal work pressure was evaluated by spreadsheet. Temperature or pressure changes were evaluated by 12- and 24-hour assays. The maximal work pressure permitted was 6.5 absolute atmospheres. Thus, the container was free from danger. The temperature inside the chamber was kept between 2 degrees and 4 degrees C. The production costs of the prototype was US$1000. The manufacture of the refrigerating hyperbaric chamber is viable, simple, and inexpensive.

IN VITRO STUDIES ON HEME OXYGENASE-1 AND P24 ANTIGEN HIV-1 LEVEL AFTERHYPERBARIC OXYGEN TREATMENTOFHIV-1 INFECTED ON PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS).

PubMed

Budiarti, Retno; Kuntaman; Nasronudin; Suryokusumo; Khairunisa, Siti Qamariyah

2018-01-01

Heme oxygenase-1 (HO-1) is a protein secreted by immune cells as a part of immune response mechanism.HO-1 can be induced by variety agents that causingoxidative stress, such as exposure to 100% oxygenat2,4 ATA pressure.It plays a vital role in maintaining cellular homeostasis.This study was conducted to identify the effect of hyperbaric oxygen exposure in cultured ofPBMCthat infected by HIV-1. Primary culture of PBMCs were isolated from 16 healthy volunteers and HIV-1 infected MT4 cell line by co-culture. The PBMCs were aliquoted into two wells as control group and treatment group. The 16 samples of HIV-1 infected PBMCwere exposed to oxygen at 2,4 ATA in animal hyperbaric chamber forthree times in 30 minutes periods with 5 minutes spacing period, that called 1 session.The Treatment done on 5 sessions within 5 days. 16 samples of HIV-1 infected PMBCs that have no hyperbaric treatment became control group.The supernatant were measured the HO-1 production by ELISA andmRNA expression of HO-1 by real time PCR and the number ofantigen p24 HIV-1by ELISA. The result showed that there was no increasing of HO-1 at both mRNA level and protein level, there was a decreasing number of antigen p24 HIV-1 at the treatment group. In addition, hyperbaric exposure could not increase the expression of HO-1, more over the viral replication might be reduced by other mechanism. Hyperbaric oxygen could increases cellular adaptive response of PBMCs infected HIV-1 through increased expression of proteins that can inhibit HIV viralreplication.

IN VITRO STUDIES ON HEME OXYGENASE-1 AND P24 ANTIGEN HIV-1 LEVEL AFTERHYPERBARIC OXYGEN TREATMENTOFHIV-1 INFECTED ON PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS)

PubMed Central

Budiarti, Retno; Kuntaman; Nasronudin; Suryokusumo; Khairunisa, Siti Qamariyah

2018-01-01

Background: Heme oxygenase-1 (HO-1) is a protein secreted by immune cells as a part of immune response mechanism.HO-1 can be induced by variety agents that causingoxidative stress, such as exposure to 100% oxygenat2,4 ATA pressure.It plays a vital role in maintaining cellular homeostasis.This study was conducted to identify the effect of hyperbaric oxygen exposure in cultured ofPBMCthat infected by HIV-1. Material and Methods: Primary culture of PBMCs were isolated from 16 healthy volunteers and HIV-1 infected MT4 cell line by co-culture. The PBMCs were aliquoted into two wells as control group and treatment group. The 16 samples of HIV-1 infected PBMCwere exposed to oxygen at 2,4 ATA in animal hyperbaric chamber forthree times in 30 minutes periods with 5 minutes spacing period, that called 1 session. The Treatment done on 5 sessions within 5 days. 16 samples of HIV-1 infected PMBCs that have no hyperbaric treatment became control group.The supernatant were measured the HO-1 production by ELISA andmRNA expression of HO-1 by real time PCR and the number ofantigen p24 HIV-1by ELISA. Results: The result showed that there was no increasing of HO-1 at both mRNA level and protein level, there was a decreasing number of antigen p24 HIV-1 at the treatment group. In addition, hyperbaric exposure could not increase the expression of HO-1, more over the viral replication might be reduced by other mechanism. Conclusions: Hyperbaric oxygen could increases cellular adaptive response of PBMCs infected HIV-1 through increased expression of proteins that can inhibit HIV viralreplication. PMID:29619425

Rectal temperature changes and oxygen toxicity in dogs treated in a monoplace chamber.

PubMed

Shmalberg, Justin; Davies, Wendy; Lopez, Stacy; Shmalberg, Danielle; Zilberschtein, Jose

2015-01-01

Hyperbaric oxygen treatments are increasingly administered to pet dogs, using veterinary-specific monoplace chambers. The basic physiologic responses, chamber performance and oxygen toxicity rates have not yet been evaluated in dogs in a clinical setting. As a result, a series of consecutive 45-minute, 2-atmospheres absolute (atm abs) hyperbaric treatments with 100% oxygen were evaluated in a veterinary rehabilitation center (n = 285). 65 dogs with a mean body weight of 21 ± 15 kg (1.4-71 kg) were treated with an average of four sessions each. The mean rectal temperature of canine patients decreased 0.07 degrees C (0.1 degrees F) during treatments (p = 0.04). Intra-chamber temperature and humidity both increased: +1.0 degrees C (1.7 degrees F, p < 0.0001) and +5.7% (p < 0.0001), respectively. The mean maximal oxygen concentration measured before depressurization of the veterinary-specific commercial chamber was 98.0 ± 0.9%. No strong correlations (r > 0.75) were identified between body weights, body condition scores, maximal oxygen concentrations, starting or ending rectal temperature, chamber humidity and chamber temperature. Oxygen toxicity was not observed during the observational period. Patients were most commonly treated for intervertebral disc disease (n = 16 dogs) and extensive traumatic wounds (n = 10 dogs), which represented a large number of the total study sessions (19% and 16%, respectively).

Topical oxygen as an adjunct to wound healing: a clinical case series.

PubMed

Kalliainen, Loree K.; Gordillo, Gayle M.; Schlanger, Richard; Sen, Chandan K.

2003-01-01

BACKGROUND: Disrupted vasculature and high energy-demand to support processing and regeneration of wounded tissue are typical characteristics of a wound site. Oxygen delivery is a critical element for the healing of wounds. Clinical experience with adjunctive hyperbaric oxygen therapy in the treatment of chronic wounds have shown that wound hyperoxia increases wound granulation tissue formation and accelerates wound contraction and secondary closure. Nevertheless, the physiologic basis for this modality remains largely unknown. Also, systemic hyperbaric oxygen therapy is associated with risks related to oxygen toxicity. Topical oxygen therapy represents a less explored modality in wound care. The advantages of topical oxygen therapy include low cost, lack of systemic oxygen toxicity, and the ability to receive treatment at home, making the benefits of oxygen therapy available to a much larger population of patients. MATERIALS AND METHODS: Over 9 months, seven surgeons treated 58 wounds in 32 patients with topical oxygen with follow-up ranging from 1 to 8 months. The data presented herein is a retrospective analysis of the results we have achieved using topical oxygen on complex wounds. RESULTS: Thirty-eight wounds in 15 patients healed while on topical oxygen. An additional five wounds in five patients had preoperative oxygen therapy; all wounds initially healed postoperatively. In two patients, wounds recurred post-healing. In ten wounds, topical oxygen had no effect; and two of those patients went on to require limb amputation. There were no complications attributable to topical oxygen. Three patients died during therapy and one died in the first postoperative month from underlying medical problems. Two patients were lost to follow-up. CONCLUSIONS: In this case series, topical oxygen had no detrimental effects on wounds and showed beneficial indications in promoting wound healing.

Hyperbaric hyperoxia alters innate immune functional properties during NASA Extreme Environment Mission Operation (NEEMO).

PubMed

Strewe, C; Crucian, B E; Sams, C F; Feuerecker, B; Stowe, R P; Choukèr, A; Feuerecker, M

2015-11-01

Spaceflight is associated with immune dysregulation which is considered as risk factor for the performance of exploration-class missions. Among the consequences of confinement and other environmental factors of living in hostile environments, the role of different oxygen concentrations is of importance as either low (e.g. as considered for lunar or Martian habitats) or high (e.g. during extravehicular activities) can trigger immune dysfunction. The aim of this study was to investigate the impact of increased oxygen availability--generated through hyperbaricity--on innate immune functions in the course of a 14 days NEEMO mission. 6 male subjects were included into a 14 days undersea deployment at the Aquarius station (Key Largo, FL, USA). The underwater habitat is located at an operating depth of 47 ft. The 2.5 times higher atmospheric pressure in the habitat leads to hyperoxia. The collection of biological samples occurred 6 days before (L-6), at day 7 (MD7) and 11/13 (MD11/13) during the mission, and 90 days thereafter (R). Blood analyses included differential blood cell count, ex vivo innate immune activation status and inhibitory competences of granulocytes. The absolute leukocyte count showed an increase during deployment as well as the granulocyte and monocyte count. Lymphocyte count was decreased on MD7. The assessments of native adhesion molecules on granulocytes (CD11b, CD62L) indicated a highly significant cellular activation (L-6 vs. MD7/MD13) during mission. In contrast, granulocytes were more sensitive towards anti-inflammatory stimuli (adenosine) on MD13. Living in the NEEMO habitat for 14 days induced significant immune alterations as seen by an activation of adhesion molecules and vice versa higher sensitivity towards inhibition. This investigation under hyperbaric hyperoxia is important especially for Astronauts' immune competence during extravehicular activities when exposed to similar conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

Effect of exposure to hyperoxic, hypobaric, and hyperbaric environments on concentrations of selected and aerobic and anaerobic fecal flora of mice.

PubMed

Gillmore, J D; Gordon, F B

1975-03-01

Alterations in selected aerobic and anaerobic fecal microflora of the mouse were determined during exposure to hyperoxic and normoxic hypo- and hyperbaric environments. Examination of fecal cultures obtained during exposure for 6 weeks to either 60 or 77% oxygen concentration 1 atmosphere absolute revealed little alteration in the aerobic or anaerobic flora. There appeared to be only a retardation in the reduction of the Klebsiella-Enterobacter flora which normally occurs after weaning. During exposure to hypobaric environments (100% O-2, 0.2 atmosphere absolute), significant alterations in concentrations of Escherichia coli, slow lactose fermenters, Klebsiella-Enterobacter, and enterococci were found in some instances. All alterations were toward increased concentrations. Variations in concentrations of different colony types of obligately anaerobic gram-positive (anGPR) and gram-negative (anGNR) rods cultured during the same experiments also occurred. One colony type of anGPR appeared to decrease while a second type increased in numbers. Concentrations of three colony types of anGNR were generally, but not always, increased. During hyperbaric exposure (2.8% O-2, 7.5 atmospheres absolute), increased concentrations of Klebsiella-Enterobacter, E. coli, slow lactose fermenters and enterococci were also noted. Changes in numbers of both colony types of anGPR, when occurring, were in the direction of lower numbers. Alteration in numbers of anGNR were in both directions but were more frequent in the direction of higher numbers. After return to normal air for 4 weeks of either hypo- or hyperbaric exposure, fecal concentrations of all organisms tended to revert toward control values with the exception of the anGPR which remained in lower concentrations after termination of the hyperbaric exposure. These observations indicate that, despite the great variation in the fecal flora among individual mice, it is possible to discover the effects induced by altered gaseous

Hyperbaric oxygen therapy stimulates colonic stem cells and induces mucosal healing in patients with refractory ulcerative colitis: a prospective case series

PubMed Central

Bekheit, Mohamed; Baddour, Nahed; Katri, Khaled; Taher, Yousry; El Tobgy, Khaled; Mousa, Essam

2016-01-01

Background Hyperbaric oxygen (HBO) is used as part of treatment in a variety of clinical conditions. Its use in the treatment of ulcerative colitis has been reported in few clinical reports. Objective We report the effect of HBO on refractory ulcerative colitis exploring one potential mechanism of action. Design A review of records of patients with refractory ulcerative colitis who received HBO was conducted. Clinical and histopathological scoring was utilised to evaluate the response to HBO therapy (HBOT). Results All patients manifested clinical improvement by the 40th cycle of HBOT. The median number of stool frequency dropped from seven motions/day (range=3–20) to 1/day (range=0.5–3), which was significant (z=−4.6, p<0.001). None of the patients manifested persistent blood passage after HBOT (z=−3.2, p=0.002). The severity index significantly improved after HBOT (z=−4.97, p<0.001). Histologically, a significant reduction of the scores of activity was recorded accompanied by a significant increase in the proliferating cell nuclear antigen labelling index of the CD44 cells of the colonic mucosa (p=0.001). Conclusions HBOT is effective in the setting of refractory ulcerative colitis. The described protocol is necessary for successful treatment. HBOT stimulates colonic stem cells to promote healing. PMID:27195128

The changes in histopathology and mass in hyperbaric oxygen-treated auricular cartilage grafts in a rabbit model.

PubMed

Bilici, Suat; Yiğit, Özgür; Dönmez, Zehra; Huq, Gülben Erdem; Aktaş, Şamil

2015-04-01

The aim of the study is to investigate the histopathologic and cartilage mass changes in hyperbaric oxygen (HBO)-treated auricular cartilage grafts either crushed or fascia wrapped in a rabbit model. This is a prospective, controlled experimental study. Sixteen rabbits were randomly allocated into control (n = 8) and treatment groups (n = 8). Each group was further grouped as crushed cartilage (n = 4) and fascia wrapped crushed cartilage (n = 4). The eight rabbits in the treatment group had HBO once daily for 10 days as total of 10 sessions. The mass of cartilage, cartilage edge layout, structural layout, staining disorders of the chondroid matrix, necrosis, calcification besides bone metaplasia, chronic inflammation in the surrounding tissues, fibrosis, and increased vascularity were evaluated in the hematoxylin and eosin (H&E)-stained sections. Fibrosis in the surrounding tissue and cartilage matrix was evaluated with Masson's trichrome stain. The toluidine blue staining was used to evaluate loss of metachromasia in matrix. The prevalence of glial fibrillary acidic protein (GFAP) staining in chondrocytes was also evaluated. Although the remaining amount of cartilage mass after implantation does not show a significant difference between the control and the study group (p = 0.322, p <0.05).The difference between control and study group in terms of positive staining with GFAP was statistically significant (p = 0.01, p <0.05). Necrosis and loss of matrix metachromasia were significantly low in the study group compared with control group (p = 0.001, p = 0.006, p <0.05). HBO therapy did not have significant effect on the mass of rabbit auricular cartilage graft. HBO therapy significantly reduced loss of metachromasia, necrosis, and GFAP staining in the auricular cartilage grafts of the animal model. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

RNA sequencing analysis reveals new findings of hyperbaric oxygen treatment on rats with acute carbon monoxide poisoning.

PubMed

Wang, Wenlan; Xue, Li; Li, Ya; Li, Rong; Xie, Xiaoping; Bao, Junxiang; Hai, Chunxu; Li, Jinsheng

2016-01-01

To elucidate the altered gene network in the brains of carbon monoxide (CO) poisoned rats after treatment with hyperbaric oxygen (HBO₂). RNA sequencing (RNA-seq) analysis was performed to examine differentially expressed genes (DEGs) in brain tissue samples from nine male rats: a normal control group; a CO poisoning group; and an HBO₂ treatment group (three rats/group). Reverse transcription polymerase chain reaction (RT-PCR) and real-time quantitative PCR were used for validation of the DEGs in another 18 male rats (six rats/group). RNA-seq revealed that two genes were upregulated (4.18 and 8.76 log to the base 2 fold change) (p⟨0.05) in the CO-poisoned rats relative to the control rats; two genes were upregulated (3.88 and 7.69 log to the base 2 fold change); and 23 genes were downregulated (3.49-15.12 log to the base 2 fold change) (p⟨0.05) in the brains of the HBO₂-treated rats relative to the CO-poisoned rats. Target prediction of DEGs by gene network analysis and analysis of pathways affected suggested that regulation of gene expressions of dopamine metabolism and nitric oxide (NO) synthesis were significantly affected by CO poisoning and HBO₂ treatment. Results of RT-PCR and real-time quantitative PCR indicated that four genes (Pomc, GH-1, Pr1 and Fshβ) associated with hormone secretion in the hypothalamic-pituitary system have potential as markers for prognosis of CO. This study is the first RNA-seq analysis profile of HBO₂ treatment on rats with acute CO poisoning. It concludes that changes of hormone secretion in the hypothalamic-pituitary system, dopamine metabolism and NO synthesis involved in brain damage and behavior abnormalities after CO poisoning and HBO₂ therapy may regulate these changes.

Effect of hyperbaric oxygen on lipid peroxidation and visual development in neonatal rats with hypoxia-ischemia brain damage.

PubMed

Chen, Jing; Chen, Yan-Hui; Lv, Hong-Yan; Chen, Li-Ting

2016-07-01

The aim of the present study was to investigate the effect of hyperbaric oxygen (HBO) on lipid peroxidation and visual development in a neonatal rat model of hypoxic-ischemic brain damage (HIBD). The rat models of HIBD were established by delayed uterus dissection and were divided randomly into two groups (10 rats each): HIBD and HBO-treated HIBD (HIBD+HBO) group. Another 20 rats that underwent sham-surgery were also divided randomly into the HBO-treated and control groups. The rats that underwent HBO treatment received HBO (0.02 MPa, 1 h/day) 24 h after the surgery and this continued for 14 days. When rats were 4 weeks old, their flash visual evoked potentials (F-VEPs) were monitored and the ultrastructures of the hippocampus were observed under transmission electron microscope. The levels of superoxide dismutase (SOD) and malonyldialdehyde (MDA) in the brain tissue homogenate were detected by xanthine oxidase and the thiobarbituric acid colorimetric method. Compared with the control group, the ultrastructures of the pyramidal neurons in the hippocampal CA3 area were distorted, the latencies of F-VEPs were prolonged (P<0.01) and the SOD activities were lower while the MDA levels were higher (P<0.01) in the HIBD group. No significant differences in ultrastructure, the latency of F-VEPs or SOD/MDA levels were identified between the HBO-treated HIBD group and the normal control group (P>0.05). HBO enhances antioxidant capacity and reduces the ultrastructural damage induced by hypoxic-ischemia, which may improve synaptic reconstruction and alleviate immature brain damage to promote the habilitation of brain function.

A ZigBee-based wireless system for monitoring vital signs in hyperbaric chambers: Technical report.

PubMed

Carmona, Cristian; Alorda, Bartomeu; Gracia, Luis; Perez-Vidal, Carlos; Salinas, Antonio

2017-01-01

This paper presents the replacement of a traditional wired communication link of the hyperbaric chambers with a wireless ZigBee-based system. This move allows a reduction in the costs of seals capable of withstanding the internal pressures and gives rise to a more versatile system. The new system is able to capture and process individual vital signs like the electrocardiography signal, and other analog sources, sending the data to an external computer and allowing analysis, representation and sharing with medical staff. This system solves such problems as the attenuation of the signal produced by the metal walls of the hyperbaric chamber and has a coverage area large enough to manage up to six patients with an effective data rate conversion of 2kHz. Furthermore, a battery-based and multiparameter platform is designed for multipatient hyperbaric chambers. Copyright© Undersea and Hyperbaric Medical Society.

A metabolic simulator for unmanned testing of breathing apparatuses in hyperbaric conditions.

PubMed

Frånberg, Oskar; Loncar, Mario; Larsson, Åke; Ornhagen, Hans; Gennser, Mikael

2014-11-01

A major part of testing of rebreather apparatuses for underwater diving focuses on the oxygen dosage system. A metabolic simulator for testing breathing apparatuses was built and evaluated. Oxygen consumption was achieved through catalytic combustion of propene. With an admixture of carbon dioxide in the propene fuel, the system allowed the respiratory exchange ratio to be set freely within human variability and also made it possible to increase test pressures above the condensation pressure of propene. The system was tested by breathing ambient air in a pressure chamber with oxygen uptake (Vo₂) ranging from 1-4 L · min(-1), tidal volume (VT) from 1-3 L, breathing frequency (f) of 20 and 25 breaths/min, and chamber pressures from 100 to 670 kPa. The measured end-tidal oxygen concentration (Fo₂) was compared to calculated end-tidal Fo₂. The largest average difference in end-tidal Fo₂during atmospheric pressure conditions was 0.63%-points with a 0.28%-point average difference during the whole test. During hyperbaric conditions with pressures ranging from 100 to 670 kPa, the largest average difference in Fo₂was 1.68%-points seen during compression from 100 kPa to 400 kPa and the average difference in Fo₂during the whole test was 0.29%-points. In combination with a breathing simulator simulating tidal breathing, the system can be used for dynamic continuous testing of breathing equipment with changes in VT, f, Vo2, and pressure.

Evolving Oxygen Landscape of the Early Atmosphere and Oceans

NASA Astrophysics Data System (ADS)

Lyons, T. W.; Reinhard, C. T.; Planavsky, N. J.

2013-12-01

The past decade has witnessed remarkable advances in our understanding of oxygen on the early Earth, and a new framework, the topic of this presentation, is now in place to address the controls on spatiotemporal distributions of oxygen and their potential relationships to deep-Earth processes. Recent challenges to the Archean biomarker record have put an added burden on inorganic geochemistry to fingerprint and quantify the early production, accumulation, and variation of biospheric oxygen. Fortunately, a wide variety of techniques now point convincingly to photosynthetic oxygen production and dynamic accumulation well before the canonical Great Oxidation Event (GOE). Recent modeling of sulfur recycling over this interval allows for transient oxygen accumulation in the atmosphere without the disappearance of non-mass-dependent (NMD) sulfur isotope anomalies from the stratigraphic record and further allows for persistent accumulation in the atmosphere well before the permanent disappearance of NMD signals. This recent work suggests that the initial rise of oxygen may have occurred in fits and starts rather than a single step, and that once permanently present in the atmosphere, oxygen likely rose to high levels and then plummeted, in phase with the Paleoproterozoic Lomagundi positive carbon isotope excursion. More than a billion years of oxygen-free conditions in the deep ocean followed and set a challenging course for life, including limited abundances and diversity of eukaryotic organisms. Despite this widespread anoxia, sulfidic (euxinic) conditions were likely limited to productive ocean margins. Nevertheless, euxinia was sufficiently widespread to impact redox-dependent nutrient relationships, particularly the availability of bioessential trace metals critical in the nitrogen cycle, which spawned feedbacks that likely maintained oxygen at very low levels in the ocean and atmosphere and delayed the arrival of animals. Then, in the mid, pre-glacial Neoproterozoic

Intravenous oxygen: a novel method of oxygen delivery in hypoxemic respiratory failure?

PubMed

Gehlbach, Jonathan A; Rehder, Kyle J; Gentile, Michael A; Turner, David A; Grady, Daniel J; Cheifetz, Ira M

2017-01-01

Hypoxemic respiratory failure is a common problem in critical care. Current management strategies, including mechanical ventilation and extracorporeal membranous oxygenation, can be efficacious but these therapies put patients at risk for toxicities associated with invasive forms of support. Areas covered: In this manuscript, we discuss intravenous oxygen (IVO 2 ), a novel method to improve oxygen delivery that involves intravenous administration of a physiologic solution containing dissolved oxygen at hyperbaric concentrations. After a brief review of the physiology behind supersaturated fluids, we summarize the current evidence surrounding IVO 2 . Expert commentary: Although not yet at the stage of clinical testing in the United States and Europe, IVO 2 has been used safely in Asia. Furthermore, preliminary laboratory data have been encouraging, suggesting that IVO 2 may play a role in the management of patients with hypoxemic respiratory failure in years to come. However, significantly more work needs to be done, including definitive evidence that such a therapy is safe, before it can be included in an intensivist's arsenal for hypoxemic respiratory failure.

A low-dose bupivacaine: a comparison of hyperbaric and hypobaric solutions for unilateral spinal anesthesia.

PubMed

Kaya, Menşure; Oğuz, Selma; Aslan, Kemal; Kadioğullari, Nihal

2004-01-01

The injection of small doses of local anesthetic solutions through pencil-point directional needles and maintaining the lateral decubitus position for 15 to 30 minutes after the injection have been suggested to facilitate the unilateral distribution of spinal anesthesia. We evaluated the effects of hypobaric and hyperbaric bupivacaine in attempting to achieve unilateral spinal anesthesia for patients undergoing lower limb orthopedic surgery. Fifty patients were randomly allocated into 2 groups to receive either 1.5 mL hyperbaric bupivacaine 0.5% (7.5 mg; n = 25) or 4.2 mL hypobaric bupivacaine 0.18% (7.5 mg; n = 25). Drugs were administered at the L3-4 interspace with the patient in the lateral position. Patients remained in this position for 15 minutes before turning supine for the operation. Spinal block was assessed by pinprick and modified Bromage scale on both sides. Unilateral spinal block was observed in 20 patients in the hyperbaric group (80%) and in 19 patients in the hypobaric group (76%) while in the lateral position. However, 15 minutes after patients were turned supine, unilateral spinal anesthesia decreased to 68% of cases in the hyperbaric group and 24% of cases in the hypobaric group (P <.05). The motor block was more intense during the first 5 and 10 minutes (P <.05), but at the end of operation there was no difference between the groups. The hemodynamic changes were similar between the groups. As a result, unilateral spinal anesthesia with hyperbaric and hypobaric bupivacaine provided a rapid motor and sensory recovery and good hemodynamic stability, but more unilateral spinal block was achieved in patients in the hyperbaric group when compared with patients in the hypobaric group.

Hyperbaric Oxygen Therapy Is Associated With Lower Short- and Long-Term Mortality in Patients With Carbon Monoxide Poisoning.

PubMed

Huang, Chien-Cheng; Ho, Chung-Han; Chen, Yi-Chen; Lin, Hung-Jung; Hsu, Chien-Chin; Wang, Jhi-Joung; Su, Shih-Bin; Guo, How-Ran

2017-11-01

To date, there has been no consensus about the effect of hyperbaric oxygen therapy (HBOT) on the mortality of patients with carbon monoxide poisoning (COP). This retrospective nationwide population-based cohort study from Taiwan was conducted to clarify this issue. Using the Nationwide Poisoning Database, we identified 25,737 patients with COP diagnosed between 1999 and 2012, including 7,278 patients who received HBOT and 18,459 patients who did not. The mortality risks of the two cohorts were compared, including overall mortality, and stratified analyses by age, sex, underlying comorbidities, monthly income, suicide attempt, drug poisoning, acute respiratory failure, and follow-up until 2013 were conducted. We also tried to identify independent mortality predictors and evaluated their effects. Patients who received HBOT had a lower mortality rate compared with patients who did not (adjusted hazard ratio [AHR], 0.74; 95% CI, 0.67-0.81) after adjusting for age, sex, underlying comorbidities, monthly income, and concomitant conditions, especially in patients younger than 20 years (AHR, 0.45; 95% CI, 0.26-0.80) and those with acute respiratory failure (AHR, 0.43; 95% CI, 0.35-0.53). The lower mortality rate was noted for a period of 4 years after treatment of the COP. Patients who received two or more sessions of HBOT had a lower mortality rate than did those who received HBOT only once. Older age, male sex, low monthly income, diabetes, malignancy, stroke, alcoholism, mental disorders, suicide attempts, and acute respiratory failure were also independent mortality predictors. HBOT was associated with a lower mortality rate in patients with COP, especially in those who were younger than 20 years and those with acute respiratory failure. The results provide important references for decision-making in the treatment of COP. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

[Spread of spinal anesthesia with 3 different hyperbaric solutions used in Japan].

PubMed

Masuda, R; Yokoyama, K; Inoue, T

1998-12-01

We studied the spread of spinal anesthesia with 3 different hyperbaric solutions commercially available in Japan. Percamin-S [0.3% dibucaine in 5% hyperbaric saline] (P), Neo-Percamin.S [0.24% dibucaine with 0.12% T-caine in 9.5% glucose] (N) and 0.5% Tetcaine [tetracaine] in 10% glucose (T) were studied. Two ml of each solution was administered intrathecally using a 25 gauge Quincke needle. Patients (n = 90) were allocated to one of 9 groups receiving 2 ml of P, N or T at L 2-3, L 3-4 or L 4-5 interspace. Both N and T produced significantly higher spread of analgesia than P at any of L 3-4 and L 4-5 interspaces. P and N have the same specific gravity, even though significant differences were found in spread of segmental analgesia. Local anesthesic agents and solvent solutions themselves are considered to influence the spread of spinal anesthesia as the specific gravity of hyperbaric solution does.

[Low dose isobaric, hyperbaric, or hypobaric bupivacaine for unilateral spinal anesthesia.].

PubMed

Imbelloni, Luiz Eduardo; Beato, Lúcia; Gouveia, Marildo A; Cordeiro, José Antônio

2007-06-01

Unilateral spinal anesthesia has its advantages, especially in patients undergoing outpatient basis surgeries. Low dose, slow speed of administration, and the lateral positioning make easier the unilateral distribution in spinal anesthesia. Isobaric, hyperbaric, and hypobaric solutions of bupivacaine were compared in the unilateral spinal anesthesia in patients undergoing outpatient basis orthopedic surgeries. One hundred and fifty patients were randomly divided in three groups to receive 5 mg of 0.5% isobaric bupivacaine (Iso Group), 5 mg of 0.5% hyperbaric bupivacaine (Hyper Group), or 5 mg of 0.15% hypobaric bupivacaine (Hypo Group). The solutions were administered in the L3-L4 space with the patient in the lateral decubitus and remaining in this position for 20 minutes. Sensitive anesthesia was evaluated by the pin prick test. Motor blockade was determined by the modified Bromage scale. Both blockades were compared with the opposite side and among themselves. There was a significant difference between the side of the surgery and the opposite side in all three groups at 20 minutes, but the frequency of unilateral spinal anesthesia was greater with the hyperbaric and hypobaric solutions. Sensitive and motor blockades were observed in 14 patients in the Iso Group, 38 patients in the Hyper Group, and 40 patients in the Hypo Group. Patients did not develop any hemodynamic changes. Postpuncture headache and transitory neurological symptoms were not observed. Spinal anesthesia with hypobaric and hyperbaric solutions present a higher frequency of unilateral anesthesia. After 20 minutes, isobaric bupivacaine mobilized into cerebrospinal fluid (CSF) resulted in unilateral spinal anesthesia in only 28% of the patients.

Reactive Oxygen Species on the Early Earth and Survival of Bacteria

NASA Technical Reports Server (NTRS)

Balk, Melikea; Mason, Paul; Stams, Alfons J. M.; Smidt, Hauke; Freund, Friedemann; Rothschild, Lynn

2011-01-01

An oxygen-rich atmosphere appears to have been a prerequisite for complex, multicellular life to evolve on Earth and possibly elsewhere in the Universe. However it remains unclear how free oxygen first became available on the early Earth. A potentially important, and as yet poorly constrained pathway, is the production of oxygen through the weathering of rocks and release into the near-surface environment. Reactive Oxygen Species (ROS), as precursors to molecular oxygen, are a key step in this process, and may have had a decisive impact on the evolution of life, present and past. ROS are generated from minerals in igneous rocks during hydrolysis of peroxy defects, which consist of pairs of oxygen anions oxidized to the valence state -1 and during (bio) transformations of iron sulphide minerals. ROS are produced and consumed by intracellular and extracellular reactions of Fe, Mn, C, N, and S species. We propose that, despite an overall reducing or neutral oxidation state of the macroenvironment and the absence of free O2 in the atmosphere, organisms on the early Earth had to cope with ROS in their microenvironments. They were thus under evolutionary pressure to develop enzymatic and other defences against the potentially dangerous, even lethal effects of oxygen and its derived ROS. Conversely it appears that microorganisms learned to take advantage of the enormous reactive potential and energy gain provided by nascent oxygen. We investigate how oxygen might be released through weathering. We test microorganisms in contact with rock surfaces and iron sulphides. We model bacteria such as Deionococcus radiodurans and Desulfotomaculum, Moorella and Bacillus species for their ability to grow or survive in the presence of ROS. We examine how early Life might have adapted to oxygen.

Laparoscopic cholecystectomy under spinal anesthesia: comparative study between conventional-dose and low-dose hyperbaric bupivacaine

PubMed Central

Imbelloni, Luiz Eduardo; Sant’Anna, Raphael; Fornasari, Marcos; Fialho, José Carlos

2011-01-01

Background Laparoscopic cholecystectomy has the advantages of causing less postoperative pain and requiring a short hospital stay, and therefore is the treatment of choice for cholelithiasis. This study was designed to compare spinal anesthesia using hyperbaric bupivacaine given as a conventional dose by lumbar puncture or as a low-dose by thoracic puncture. Methods A total of 140 patients with symptomatic gallstone disease were randomized to undergo laparoscopic cholecystectomy with low-pressure CO2 pneumoperitoneum under spinal anesthesia using either conventional lumbar spinal anesthesia (hyperbaric bupivacaine 15 mg and fentanyl 20 mg) or low-dose thoracic spinal anesthesia (hyperbaric bupivacaine 7.5 mg and fentanyl 20 μg). Intraoperative parameters, postoperative pain, complications, recovery time, and patient satisfaction at follow-up were compared between the two treatment groups. Results All procedures were completed under spinal anesthesia, with no cases needing conversion to general anesthesia. Values for time for block to reach the T3 dermatomal level, duration of motor and sensory block, and hypotensive events were significantly lower with low-dose bupivacaine. Postoperative pain was higher for low-dose hyperbaric bupivacaine at 6 and 12 hours. All patients were discharged after 24 hours. Follow-up 1 week postoperatively showed all patients to be satisfied and to be keen advocates of spinal anesthesia. Conclusion Laparoscopic cholecystectomy can be performed successfully under spinal anesthesia. A small dose of hyperbaric bupivacaine 7.5 mg and 20 μg fentanyl provides adequate spinal anesthesia for laparoscopy and, in comparison with hyperbaric bupivacaine 15% and fentanyl 20 μg, causes markedly less hypotension. The low-dose strategy may have an advantage in ambulatory patients because of the earlier recovery of motor and sensory function and earlier discharge. PMID:22915892

Continuous glucose monitoring--a study of the Enlite sensor during hypo- and hyperbaric conditions.

PubMed

Adolfsson, Peter; Örnhagen, Hans; Eriksson, Bengt M; Cooper, Ken; Jendle, Johan

2012-06-01

The performance and accuracy of the Enlite(™) (Medtronic, Inc., Northridge, CA) sensor may be affected by microbubble formation at the electrode surface during hypo- and hyperbaric conditions. The effects of acute pressure changes and of prewetting of sensors were investigated. On Day 1, 24 sensors were inserted on the right side of the abdomen and back in one healthy individual; 12 were prewetted with saline solution, and 12 were inserted dry. On Day 2, this procedure was repeated on the left side. All sensors were attached to an iPro continuous glucose monitoring (CGM) recorder. Hypobaric and hyperbaric tests were conducted in a pressure chamber, with each test lasting 105 min. Plasma glucose values were obtained at 5-min intervals with a HemoCue(®) (Ängelholm, Sweden) model 201 glucose analyzer for comparison with sensor glucose values. Ninety percent of the CGM systems operated during the tests. The mean absolute relative difference was lower during hyperbaric than hypobaric conditions (6.7% vs. 14.9%, P<0.001). Sensor sensitivity was slightly decreased (P<0.05) during hypobaric but not during hyperbaric conditions. Clarke Error Grid Analysis showed that 100% of the values were found in the A+B region. No differences were found between prewetted and dry sensors. The Enlite sensor performed adequately during acute pressure changes and was more accurate during hyperbaric than hypobaric conditions. Prewetting the sensors did not improve accuracy. Further studies on type 1 diabetes subjects are needed under various pressure conditions.

Neurotoxicity of subarachnoid hyperbaric bupivacaine in dogs.

PubMed

Ganem, E M; Vianna, P T; Marques, M; Castiglia, Y M; Vane, L A

1996-01-01

The study investigated possible neurotoxic effects of increasing concentrations and doses of bupivacaine administered into the subarachnoid space in dogs. Fifty animals were allocated to five experimental groups: G1, control; G2, 5 mg 0.5 bupivacaine in 10% glucose solution; G3, 10 mg of 1% bupivacaine in 10% glucose solution; G4, 20 mg 2% bupivacaine in 10% glucose solution, and G5, 20 mg 2% bupivacaine in water. After 72 hours of observation, the animals were killed and the spinal cords removed for histologic examination by light microscopy. None of the animals showed any neurologic clinical disturbance following recovery from spinal anesthesia. One case of necrosis of nerve tissue was observed in G3 and four in G4. Increasing concentrations and doses of hyperbaric bupivacaine solutions increased the incidence of nerve tissue damage, which did not occur with hypobaric solutions. These results should contribute to the further understanding of neurologic complications following spinal anesthesia when large doses of local anesthetics in hyperbaric solutions are used.

Development and preliminary test of a new plateau hyperbaric chamber.

PubMed

Sun, Liang; Ding, Meng-jiang; Cai, Tian-cai; Fan, Hao-jun; Zhang, Jian-peng

2015-10-01

The objective of this study is to validate the performance, define its limits, and provide details on a new plateau hyperbaric chamber at 355-, 2880-, and 4532-m high altitude. A new multiplace plateau hyperbaric chamber was designed to satisfy the needed of patients who have acute mountain sickness. Tests were conducted inside the chamber at 355-, 2880-, and 4532-m high altitude. The safely and conveniences of the new plateau hyperbaric chamber were estimated. Minimum pressures of the main compartment can reach up to 0.029, 0.022, and 0.02 MPa at 355-, 2880-, and 4532-m high altitude. During pressurization, there was no leak of air around the chamber. The time lag of pressure equilibration between main and buffer compartment varies from 30.3±2.01 to 200.5±5.44 seconds and between buffer compartment and ambient pressure varies from 60.2±4.13 to 215.9±6.76 seconds. The chamber can be applicated for acute mountain sickness treatment safety and convenience. However, further experience about animals and human within the chamber is needed to improve the hardware and establish conditions of effective utilization of this equipment in the high altitude. Copyright © 2015. Published by Elsevier Inc.

Effect of shielding gas composition on the properties of hyperbaric GMA welds in duplex steels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ware, N.; Dos Santos, J.F.; Richardson, I.

1994-12-31

By using Ar/He based shielding gas mixtures with a variety of oxygen and nitrogen additions the absorption of active gas components into duplex stainless steels welded under hyperbaric conditions was examined. The pressure levels used corresponded to seawater depths of 100m, 200m and 300m. The GMAW process in the short circuit transfer mode was used for all tests. Both bead-on-plate and ``V`` butt joints were carried out. The effect of variations in the weld metal active gas components on the weld metal chemical composition and phase balance was investigated. In a second set of tests the effect of varying heatmore » inputs on the phase balance and microstructure was assessed.« less

Effect of hyperbaric oxygen on BDNF-release and neuroprotection: Investigations with human mesenchymal stem cells and genetically modified NIH3T3 fibroblasts as putative cell therapeutics.

PubMed

Schulze, Jennifer; Kaiser, Odett; Paasche, Gerrit; Lamm, Hans; Pich, Andreas; Hoffmann, Andrea; Lenarz, Thomas; Warnecke, Athanasia

2017-01-01

Hyperbaric oxygen therapy (HBOT) is a noninvasive widely applied treatment that increases the oxygen pressure in tissues. In cochlear implant (CI) research, intracochlear application of neurotrophic factors (NTFs) is able to improve survival of spiral ganglion neurons (SGN) after deafness. Cell-based delivery of NTFs such as brain-derived neurotrophic factor (BDNF) may be realized by cell-coating of the surface of the CI electrode. Human mesenchymal stem cells (MSC) secrete a variety of different neurotrophic factors and may be used for the development of a biohybrid electrode in order to release endogenously-derived neuroprotective factors for the protection of residual SGN and for a guided outgrowth of dendrites in the direction of the CI electrode. HBOT could be used to influence cell behaviour after transplantation to the inner ear. The aim of this study was to investigate the effect of HBOT on the proliferation, BDNF-release and secretion of neuroprotective factors. Thus, model cells (an immortalized fibroblast cell line (NIH3T3)-native and genetically modified) and MSCs were repeatedly (3 x - 10 x) exposed to 100% oxygen at different pressures. The effects of HBO on cell proliferation were investigated in relation to normoxic and normobaric conditions (NOR). Moreover, the neuroprotective and neuroregenerative effects of HBO-treated cells were analysed by cultivation of SGN in conditioned medium. Both, the genetically modified NIH3T3/BDNF and native NIH3T3 fibroblasts, showed a highly significant increased proliferation after five days of HBOT in comparison to normoxic controls. By contrast, the number of MSCs was decreased in MSCs treated with 2.0 bar of HBO. Treating SGN cultures with supernatants of fibroblasts and MSCs significantly increased the survival rate of SGN. HBO treatment did not influence (increase / reduce) this effect. Secretome analysis showed that HBO treatment altered the protein expression pattern in MSCs.

Large Acrylic Spherical Windows In Hyperbaric Underwater Photography

NASA Astrophysics Data System (ADS)

Lones, Joe J.; Stachiw, Jerry D.

1983-10-01

Both acrylic plastic and glass are common materials for hyperbaric optical windows. Although glass continues to be used occasionally for small windows, virtually all large viewports are made of acrylic. It is easy to uderstand the wide use of acrylic when comparing design properties of this plastic with those of glass, and glass windows are relatively more difficult to fabricate and use. in addition there are published guides for the design and fabrication of acrylic windows to be used in the hyperbaric environment of hydrospace. Although these procedures for fabricating the acrylic windows are somewhat involved, the results are extremely reliable. Acrylic viewports are now fabricated to very large sizes for manned observation or optical quality instrumen tation as illustrated by the numerous acrylic submersible vehicle hulls for hu, an occupancy currently in operation and a 3600 large optical window recently developed for the Walt Disney Circle Vision under-water camera housing.

HSP70 protects rats and hippocampal neurons from central nervous system oxygen toxicity by suppression of NO production and NF-κB activation.

PubMed

Yi, Hongjie; Huang, Guoyang; Zhang, Kun; Liu, Shulin; Xu, Weigang

2018-05-01

During diving, central nervous system oxygen toxicity may cause drowning or barotrauma, which has dramatically limited the working benefits of hyperbaric oxygen in underwater operations and clinical applications. The aim of this study is to understand the effects and the underlying mechanism of heat shock protein 70 on central nervous system oxygen toxicity and its mechanisms in vivo and in vitro. Rats were given geranylgeranylacetone (800 mg/kg) orally to induce hippocampal expression of heat shock protein 70 and then treated with hyperbaric oxygen. The time course of hippocampal heat shock protein 70 expression after geranylgeranylacetone administration was measured. Seizure latency and first electrical discharge were recorded to evaluate the effects of HSP70 on central nervous system oxygen toxicity. Effects of inhibitors of nitric oxide synthase and nuclear factor-κB on the seizure latencies and changes in nitric oxide, nitric oxide synthase, and nuclear factor-κB levels in the hippocampus tissues were examined. In cell experiments, hippocampal neurons were transfected with a virus vector carrying the heat shock protein 70 gene (H3445) before hyperbaric oxygen treatment. Cell viability, heat shock protein 70 expression, nitric oxide, nitric oxide synthase, and NF-κB levels in neurons were measured. The results showed that heat shock protein 70 expression significantly increased and peaked at 48 h after geranylgeranylacetone was given. Geranylgeranylacetone prolonged the first electrical discharge and seizure latencies, which was reversed by neuronal nitric oxide synthase, inducible nitric oxide synthase and NF-κB inhibitors. Nitric oxide, nitric oxide synthase, and inducible nitric oxide synthase levels in the hippocampus were significantly increased after hyperbaric oxygen exposure, but reversed by geranylgeranylacetone, while heat shock protein 70 inhibitor quercetin could inhibit this effect of geranylgeranylacetone. In the in vitro study, heat shock

Report on computation of repetitive hyperbaric-hypobaric decompression tables

NASA Technical Reports Server (NTRS)

Edel, P. O.

1975-01-01

The tables were constructed specifically for NASA's simulated weightlessness training program; they provide for 8 depth ranges covering depths from 7 to 47 FSW, with exposure times of 15 to 360 minutes. These tables were based up on an 8 compartment model using tissue half-time values of 5 to 360 minutes and Workmanline M-values for control of the decompression obligation resulting from hyperbaric exposures. Supersaturation ratios of 1.55:1 to 2:1 were used for control of ascents to altitude following such repetitive dives. Adequacy of the method and the resultant tables were determined in light of past experience with decompression involving hyperbaric-hypobaric interfaces in human exposures. Using these criteria, the method showed conformity with empirically determined values. In areas where a discrepancy existed, the tables would err in the direction of safety.

Pain in the elderly: Prospective study of hyperbaric CO2 cryotherapy (neurocryostimulation).

PubMed

Chatap, Guy; De Sousa, Annabelle; Giraud, Karine; Vincent, Jean-Pierre

2007-12-01

To evaluate the analgesic effects of hyperbaric CO(2) cryotherapy in elderly inpatients. An open-label prospective study was conducted in two geriatrics departments in patients with a broad range of pain characteristics. Each patient underwent a physical evaluation followed by hyperbaric CO(2) cryotherapy sessions, whose spacing and number were at the discretion of the physiotherapist. Patients completed a 100-mm visual analog scale for pain severity before and after the sessions. We included 51 patients, who were treated between May 2 and June 30, 2005. Mean age was 83.7years, and the female-to-male ratio was 4/1. The patients had acute or chronic pain whose origin was usually musculoskeletal (80.3%) or neurological (18.6%). Pain scores decreased significantly after four sessions, from 52mm to 13mm (P<0.001) in patients with acute pain and from 45mm to 13mm (P<0.001) in those with chronic pain. Hyperbaric CO(2) cryotherapy is an innovative tool that should be incorporated within the non-pharmacological armamentarium for achieving pain relief in older patients.

Underwater and hyperbaric medicine as a branch of occupational and environmental medicine.

PubMed

Lee, Young Il; Ye, Byeong Jin

2013-12-19

Exposure to the underwater environment for occupational or recreational purposes is increasing. As estimated, there are around 7 million divers active worldwide and 300,000 more divers in Korea. The underwater and hyperbaric environment presents a number of risks to the diver. Injuries from these hazards include barotrauma, decompression sickness, toxic effects of hyperbaric gases, drowning, hypothermia, and dangerous marine animals. For these reasons, primary care physicians should understand diving related injuries and assessment of fitness to dive. However, most Korean physicians are unfamiliar with underwater and hyperbaric medicine (UHM) in spite of scientific and practical values.From occupational and environmental medicine (OEM) specialist's perspective, we believe that UHM should be a branch of OEM because OEM is an area of medicine that deals with injuries caused by physical and biological hazards, clinical toxicology, occupational diseases, and assessment of fitness to work. To extend our knowledge about UHM, this article will review and update on UHM including barotrauma, decompression illness, toxicity of diving gases and fitness for diving.

Effect of growth hormone, hyperbaric oxygen and combined therapy on the gastric serosa

PubMed Central

Adas, Gokhan; Adas, Mine; Arikan, Soykan; Sarvan, Ahu Kemik; Toklu, Akin Savas; Mert, Selva; Barut, Gul; Kamali, Sedat; Koc, Bora; Tutal, Firat

2013-01-01

AIM: To investigate the role of growth hormone (GH), hyperbaric oxygen therapy (HBOT) and combined therapy on the intestinal neomucosa formation of the gastric serosa. METHODS: Forty-eight male Wistar-albino rats, weighing 250-280 g, were used in this study. The rats were divided into four groups (n = 12): Group 1, control, gastric serosal patch; Group 2, gastric serosal patch + GH; Group 3, gastric serosal patch + HBOT; and Group 4, gastric serosal patch + GH + HBOT. Abdominal access was achieved through a midline incision, and after the 1-cm-long defect was created in the jejunum, a 1 cm × 1 cm patch of the gastric corpus was anastomosed to the jejunal defect. Venous blood samples were taken to determine the insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein 3 (IGFBP-3) basal levels. HBOT was performed in Groups 3 and 4. In Groups 2 and 4, human GH was given subcutaneously at a dose of 2 mg per kg/d for 28 d, beginning on the operation day. All animals were sacrificed 60 d after surgery. The jejunal segment and the gastric anastomotic area were excised for histological examination. The inflammatory process, granulation, collagen deposition and fibroblast activity at the neomucosa formation were studied and scored. Additionally, the villus density, villus height, and crypt depth were counted and recorded. The measurements of villus height and crypt depth were calculated with an ocular micrometer. New vessel growth was determined by calculatingeach new vessel in a 1 mm2 area. RESULTS: In the histological comparison of groups, no significant differences were observed between the control group and Groups 2 and 3 with respect to epithelialization, granulation, fibroblastic activity and the inflammatory process, but significant differences were present between the control group and all others groups (Groups 2-4) with respect to angiogenesis (P < 0.01) and collagen deposition (P < 0.05, P < 0.01). Significant differences between the

Cognitive Function in a Traumatic Brain Injury Hyperbaric Oxygen Randomized Trial

DTIC Science & Technology

2015-08-07

oxygen at 2.4 atm abs. Eggum and Hunter [39] experimented with canine mesenchymal stem cells under various levels of pres- sure, oxygen, glucose...and conditioned medium. The culture system showed no cytotoxicity and was able to demonstrate that the proliferation and metabolism of mesenchymal...neurodegenerative diseases and peripheral neuropathies. He concludes that while the direct mechanisms by which transection, mechanical strain, ischemia

Efficacy of N-Butylphthalide and Hyperbaric Oxygen Therapy on Cognitive Dysfunction in Patients with Delayed Encephalopathy After Acute Carbon Monoxide Poisoning.

PubMed

Xiang, Wenping; Xue, Hui; Wang, Baojun; Li, Yuechun; Zhang, Jun; Jiang, Changchun; Pang, Jiangxia

2017-03-29

BACKGROUND Delayed encephalopathy after acute carbon monoxide (CO) poisoning (DEACMP) is one of the most serious complications after CO poisoning. This study was conducted to explore the efficacy of the combined application of N-Butylphthalide and hyperbaric oxygenation therapy (HBO) on cognitive dysfunction in patients with DEACMP. MATERIAL AND METHODS A total of 184 patients with DEACMP were randomly assigned to either receive HBO or N-Butylphthalide and HBO. Meanwhile, all patients received conventional treatment. The total remission rate (RR) was used to assess the clinical efficacy. The Mini-Mental State Examination (MMSE) was used to assess the cognitive function, and the National Institutes of Health Stroke Scale (NIHSS) was used to assess the neurological function. RESULTS Finally, there were 90 and 94 patients in the control and experimental groups, respectively. After eight weeks of treatment, the total RR in the experimental group (47.9%) was significantly higher than that in the control group (33.3%). Compared to the control group, significantly more patients in the experimental group had MMSE scores of 24-30. The lower NIHSS score in the experimental group showed that N-Butylphthalide had the effect of preservation and restoration of neurological function. No obvious drug toxicity or liver and kidney dysfunction was observed, and there was no significant change in the level of blood glucose and blood lipids. CONCLUSIONS These results indicated that the combined application of N-Butylphthalide and HBO could significantly improve the cognitive dysfunction of patients with DEACMP and have great clinical efficacy, which should be further studied.

Combined application of dexamethasone and hyperbaric oxygen therapy yields better efficacy for patients with delayed encephalopathy after acute carbon monoxide poisoning.

PubMed

Xiang, Wenping; Xue, Hui; Wang, Baojun; Li, Yuechun; Zhang, Jun; Jiang, Changchun; Liang, Furu; Pang, Jiangxia; Yu, Lehua

2017-01-01

Delayed encephalopathy after acute carbon monoxide (CO) poisoning (DEACMP) commonly occurs after recovering from acute CO poisoning. This study was performed to assess the efficacy of the combined application of dexamethasone and hyperbaric oxygen (HBO) therapy in patients with DEACMP. A total of 120 patients with DEACMP were recruited and randomly assigned into the experimental group (receiving dexamethasone 5 mg/day or 10 mg/day plus HBO therapy) and control group (HBO therapy as monotherapy). Meanwhile, the conventional treatments were provided for all the patients. We used the Mini-Mental State Examination (MMSE) scale to assess the cognitive function, the National Institutes of Health Stroke Scale (NIHSS) to assess the neurological function and the remission rate (RR) to assess the clinical efficacy. Myelin basic protein (MBP) in the cerebrospinal fluid (CSF) was also measured. After 4 weeks of treatment, compared to the control group, the experimental group had a significantly higher remission rate ( P =0.032), a significantly higher average MMSE score ( P =0.037) and a significantly lower average NIHSS score ( P =0.002). Meanwhile, there was a trend toward better improvement with dexamethasone 10 mg/day, and the level of MBP in the CSF of patients was significantly lower in the experimental group than in the control group ( P <0.0001). The addition of dexamethasone did not significantly increase the incidence of adverse events. These results indicate that the combined application of dexamethasone and HBO therapy could yield better efficacy for patients with DEACMP and should be viewed as a potential new therapy.

Recovery of Repressed Memories in Fibromyalgia Patients Treated With Hyperbaric Oxygen – Case Series Presentation and Suggested Bio-Psycho-Social Mechanism

PubMed Central

Efrati, Shai; Hadanny, Amir; Daphna-Tekoah, Shir; Bechor, Yair; Tiberg, Kobi; Pik, Nimrod; Suzin, Gil; Lev-Wiesel, Rachel

2018-01-01

Fibromyalgia Syndrome (FMS) is a condition considered to represent a prototype of central sensitization syndrome, characterized by chronic widespread pain and along with symptoms of fatigue, non-restorative sleep and cognitive difficulties. FMS can be induced by trauma, infection or emotional stress with cumulative evidence that dissociation is relatively frequent in FMS patients. Two randomized controlled trials have shown that hyperbaric oxygen therapy (HBOT) can induce neuroplasticity and be effective in patients suffering from FMS. In this paper we present, for the first time, case series of female fibromyalgia patients who, in the course of HBOT, suddenly recalled repressed traumatic memories of childhood sexual abuse (CSA). The surfacing of the repressed (dissociative) memories decades after the sexual abuse events was sudden and utterly surprising. No psychological intervention was involved. As the memories surfaced, the physical pain related to FMS subsided. In one patient who had brain single photon emission CT (SPECT) before and after HBOT, the prefrontal cortex appeared suppressed before and reactivated after. The 3 cases reported in this article are representative of a total of nine fibromyalgia patients who experienced a retrieval of repressed memory during HBOT. These cases provide insights on dissociative amnesia and suggested mechanism hypothesis that is further discussed in the article. Obviously, prospective studies cannot be planned since patients are not aware of their repressed memories. However, it is very important to keep in mind the possibility of surfacing memories when treating fibromyalgia patients with HBOT or other interventions capable of awakening dormant brain regions. PMID:29896150

Increased intrapulmonary retention of radiolabeled neutrophils in early oxygen toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rinaldo, J.E.; English, D.; Levine, J.

1988-02-01

Sequential lung injuries, such as oxygen toxicity followed by septicemia, are common during the adult respiratory distress syndrome (ARDS). As these forms of vascular injury may be mediated in part by polymorphonuclear leukocytes (PMN), aberrant interactions between PMN and previously injured pulmonary endothelium are of both theoretical interest and clinical importance. The present study was undertaken to test the hypothesis that early oxygen toxicity at a dose that injuries pulmonary endothelium relatively selectively alters intrapulmonary neutrophil kinetics. Unanesthetized rats breathing 1.0 atmospheres oxygen for 36 h showed ultrastructural endothelial damage but no edema, injury, or neutrophilic inflammation by histologic criteria.more » However, in these oxygen-toxic animals, whereas initial accumulation of radiolabeled PMN in lungs was normal, washout of PMN was abnormal at 120 min after infusion, at which point the pulmonary retention of radiolabeled PMN in the lungs of oxygen-treated animals was significantly higher than in control animals (139% of control, p less than 0.0096). Features of our methodology, including avoidance of osmotic stress and use of paired control animals, appear to have greatly enhanced the sensitivity of radiolabeled neutrophils for detecting a subtle abnormality of neutrophil-endothelial interactions. Our studies in the oxygen toxicity model provide the first demonstration in vivo of abnormal intrapulmonary neutrophil kinetics in early oxygen toxicity prior to the onset of histologic evidence of lung injury or inflammation.« less

Oxygenation history of the Neoproterozoic to early Phanerozoic and the rise of land plants

NASA Astrophysics Data System (ADS)

Wallace, Malcolm W.; Hood, Ashleigh vS.; Shuster, Alice; Greig, Alan; Planavsky, Noah J.; Reed, Christopher P.

2017-05-01

There has been extensive debate about the history of Earth's oxygenation and the role that land plant evolution played in shaping Earth's ocean-atmosphere system. Here we use the rare earth element patterns in marine carbonates to monitor the structure of the marine redox landscape through the rise and diversification of animals and early land plants. In particular, we use the relative abundance of cerium (Ceanom), the only redox-sensitive rare earth element, in well-preserved marine cements and other marine precipitates to track seawater oxygen levels. Our results indicate that there was only a moderate increase in oceanic oxygenation during the Ediacaran (average Cryogenian Ceanom = 1.1, average Ediacaran Ceanom = 0.62), followed by a decrease in oxygen levels during the early Cambrian (average Cryogenian Ceanom = 0.90), with significant ocean anoxia persisting through the early and mid Paleozoic (average Early Cambrian-Early Devonian Ceanom = 0.84). It was not until the Late Devonian that oxygenation levels are comparable to the modern (average of all post-middle Devonian Ceanom = 0.55). Therefore, this work confirms growing evidence that the oxygenation of the Earth was neither unidirectional nor a simple two-stage process. Further, we provide evidence that it was not until the Late Devonian, when large land plants and forests first evolved, that oxygen levels reached those comparable to the modern world. This is recorded with the first modern-like negative Ceanom (values <0.6) occurring at around 380 Ma (Frasnian). This suggests that land plants, rather than animals, are the 'engineers' responsible for the modern fully oxygenated Earth system.

Abdominal girth and vertebral column length aid in predicting intrathecal hyperbaric bupivacaine dose for elective cesarean section

PubMed Central

Wei, Chang-Na; Zhou, Qing-He; Wang, Li-Zhong

2017-01-01

Abstract Currently, there is no consensus on how to determine the optimal dose of intrathecal bupivacaine for an individual undergoing an elective cesarean section. In this study, we developed a regression equation between intrathecal 0.5% hyperbaric bupivacaine volume and abdominal girth and vertebral column length, to determine a suitable block level (T5) for elective cesarean section patients. In phase I, we analyzed 374 parturients undergoing an elective cesarean section that received a suitable dose of intrathecal 0.5% hyperbaric bupivacaine after a combined spinal-epidural (CSE) was performed at the L3/4 interspace. Parturients with T5 blockade to pinprick were selected for establishing the regression equation between 0.5% hyperbaric bupivacaine volume and vertebral column length and abdominal girth. Six parturient and neonatal variables, intrathecal 0.5% hyperbaric bupivacaine volume, and spinal anesthesia spread were recorded. Bivariate line correlation analyses, multiple line regression analyses, and 2-tailed t tests or chi-square test were performed, as appropriate. In phase II, another 200 parturients with CSE for elective cesarean section were enrolled to verify the accuracy of the regression equation. In phase I, a total of 143 parturients were selected to establish the following regression equation: YT5 = 0.074X1 − 0.022X2 − 0.017 (YT5 = 0.5% hyperbaric bupivacaine volume for T5 block level; X1 = vertebral column length; and X2 = abdominal girth). In phase II, a total of 189 participants were enrolled in the study to verify the accuracy of the regression equation, and 155 parturients with T5 blockade were deemed eligible, which accounted for 82.01% of all participants. This study evaluated parturients with T5 blockade to pinprick after a CSE for elective cesarean section to establish a regression equation between parturient vertebral column length and abdominal girth and 0.5% hyperbaric intrathecal bupivacaine volume. This equation

Abdominal girth and vertebral column length aid in predicting intrathecal hyperbaric bupivacaine dose for elective cesarean section.

PubMed

Wei, Chang-Na; Zhou, Qing-He; Wang, Li-Zhong

2017-08-01

Currently, there is no consensus on how to determine the optimal dose of intrathecal bupivacaine for an individual undergoing an elective cesarean section. In this study, we developed a regression equation between intrathecal 0.5% hyperbaric bupivacaine volume and abdominal girth and vertebral column length, to determine a suitable block level (T5) for elective cesarean section patients.In phase I, we analyzed 374 parturients undergoing an elective cesarean section that received a suitable dose of intrathecal 0.5% hyperbaric bupivacaine after a combined spinal-epidural (CSE) was performed at the L3/4 interspace. Parturients with T5 blockade to pinprick were selected for establishing the regression equation between 0.5% hyperbaric bupivacaine volume and vertebral column length and abdominal girth. Six parturient and neonatal variables, intrathecal 0.5% hyperbaric bupivacaine volume, and spinal anesthesia spread were recorded. Bivariate line correlation analyses, multiple line regression analyses, and 2-tailed t tests or chi-square test were performed, as appropriate. In phase II, another 200 parturients with CSE for elective cesarean section were enrolled to verify the accuracy of the regression equation.In phase I, a total of 143 parturients were selected to establish the following regression equation: YT5 = 0.074X1 - 0.022X2 - 0.017 (YT5 = 0.5% hyperbaric bupivacaine volume for T5 block level; X1 = vertebral column length; and X2 = abdominal girth). In phase II, a total of 189 participants were enrolled in the study to verify the accuracy of the regression equation, and 155 parturients with T5 blockade were deemed eligible, which accounted for 82.01% of all participants.This study evaluated parturients with T5 blockade to pinprick after a CSE for elective cesarean section to establish a regression equation between parturient vertebral column length and abdominal girth and 0.5% hyperbaric intrathecal bupivacaine volume. This equation can accurately

Renal Blood Flow, Glomerular Filtration Rate, and Renal Oxygenation in Early Clinical Septic Shock.

PubMed

Skytte Larsson, Jenny; Krumbholz, Vitus; Enskog, Anders; Bragadottir, Gudrun; Redfors, Bengt; Ricksten, Sven-Erik

2018-06-01

Data on renal hemodynamics, function, and oxygenation in early clinical septic shock are lacking. We therefore measured renal blood flow, glomerular filtration rate, renal oxygen consumption, and oxygenation in patients with early septic shock. Prospective comparative study. General and cardiothoracic ICUs. Patients with norepinephrine-dependent early septic shock (n = 8) were studied within 24 hours after arrival in the ICU and compared with postcardiac surgery patients without acute kidney injury (comparator group, n = 58). None. Data on systemic hemodynamics and renal variables were obtained during two 30-minute periods. Renal blood flow was measured by the infusion clearance of para-aminohippuric acid, corrected for renal extraction of para-aminohippuric acid. Renal filtration fraction was measured by renal extraction of chromium-51 labeled EDTA. Renal oxygenation was estimated from renal oxygen extraction. Renal oxygen delivery (-24%; p = 0.037) and the renal blood flow-to-cardiac index ratio (-21%; p = 0.018) were lower, renal vascular resistance was higher (26%; p = 0.027), whereas renal blood flow tended to be lower (-19%; p = 0.068) in the septic group. Glomerular filtration rate (-32%; p = 0.006) and renal sodium reabsorption (-29%; p = 0.014) were both lower in the septic group. Neither renal filtration fraction nor renal oxygen consumption differed significantly between groups. Renal oxygen extraction was significantly higher in the septic group (28%; p = 0.022). In the septic group, markers of tubular injury were elevated. In early clinical septic shock, renal function was lower, which was accompanied by renal vasoconstriction, a lower renal oxygen delivery, impaired renal oxygenation, and tubular sodium reabsorption at a high oxygen cost compared with controls.

Microfluidic wound bandage: localized oxygen modulation of collagen maturation.

PubMed

Lo, Joe F; Brennan, Martin; Merchant, Zameer; Chen, Lin; Guo, Shujuan; Eddington, David T; DiPietro, Luisa A

2013-01-01

Restoring tissue oxygenation has the potential to improve poorly healing wounds with impaired microvasculature. Compared with more established wound therapy using hyperbaric oxygen chambers, topical oxygen therapy has lower cost and better patient comfort, although topical devices have provided inconsistent results. To provide controlled topical oxygen while minimizing moisture loss, a major issue for topical oxygen, we have devised a novel wound bandage based on microfluidic diffusion delivery of oxygen. In addition to modulating oxygen from 0 to 100% in 60 seconds rise time, the microfluidic oxygen bandage provides a conformal seal around the wound. When 100% oxygen is delivered, it penetrates wound tissues as measured in agar phantom and in vivo wounds. Using this microfluidic bandage, we applied the oxygen modulation to 8 mm excisional wounds prepared on diabetic mice. Treatment with the microfluidic bandage demonstrated improved collagen maturity in the wound bed, although only marginal differences were observed in total collagen, microvasculature, and external closure rates. Our results show that proper topical oxygen can improve wound parameters underneath the surface. Because of the ease of fabrication, the oxygen bandage represents an economical yet practical method for oxygen wound research. © 2013 by the Wound Healing Society.

Bubble number saturation curve and asymptotics of hypobaric and hyperbaric exposures.

PubMed

Wienke, B R

1991-12-01

Within bubble number limits of the varying permeability and reduced gradient bubble models, it is shown that a linear form of the saturation curve for hyperbaric exposures and a nearly constant decompression ratio for hypobaric exposures are simultaneously recovered from the phase volume constraint. Both limits are maintained within a single bubble number saturation curve. A bubble term, varying exponentially with inverse pressure, provides closure. Two constants describe the saturation curve, both linked to seed numbers. Limits of other decompression models are also discussed and contrasted for completeness. It is suggested that the bubble number saturation curve thus provides a consistent link between hypobaric and hyperbaric data, a link not established by earlier decompression models.

Aggregation of Lens Crystallins in an In Vivo Hyperbaric Oxygen Guinea Pig Model of Nuclear Cataract: Dynamic Light-Scattering and HPLC Analysis

PubMed Central

Simpanya, M. Francis; Ansari, Rafat R.; Suh, Kwang I.; Leverenz, Victor R.; Giblin, Frank J.

2006-01-01

Purpose The role of oxygen in the formation of lens high-molecular-weight (HMW) protein aggregates during the development of human nuclear cataract is not well understood. The purpose of this study was to investigate lens crystallin aggregate formation in hyperbaric oxygen (HBO)–treated guinea pigs by using in vivo and in vitro methods. Methods Guinea pigs were treated three times weekly for 7 months with HBO, and lens crystallin aggregation was investigated in vivo with the use of dynamic light-scattering (DLS) and in vitro by HPLC analysis of water-insoluble (WI) proteins. DLS measurements were made every 0.1 mm across the 4.5- to 5.0-mm optical axis of the guinea pig lens. Results The average apparent diameter of proteins in the nucleus (the central region) of lenses of HBO-treated animals was nearly twice that of the control animals (P < 0.001). Size distribution analysis conducted at one selected point in the nucleus and cortex (the outer periphery of the lens) after dividing the proteins into small-diameter and large-diameter groups, showed in the O2-treated nucleus a threefold increase in intensity (P < 0.001) and a doubling in apparent size (P = 0.03) of large-diameter aggregate proteins, compared with the same control group. No significant changes in apparent protein diameter were detected in the O2-treated cortex, compared with the control. The average diameter of protein aggregates at the single selected location in the O2-treated nucleus was estimated to be 150 nm, a size capable of scattering light and similar to the size of aggregates found in human nuclear cataracts. HPLC analysis indicated that one half of the experimental nuclear WI protein fraction (that had been dissolved in guanidine) consisted of disulfide cross-linked 150- to 1000-kDa aggregates, not present in the control. HPLC-isolated aggregates contained αA-, β-, γ-, and ζ-crystallins, but not αB-crystallin, which is devoid of −SH groups and thus does not participate in disulfide

Commentary: Hyperbaric oxygen treatment for wounds - evidence and the Sword of Damocles.

PubMed

Laden, Gerard

2015-12-01

Increased access to any treatment sensibly follows the clinical and cost benefit being established. For many treatments this requires multiple, high-quality clinical trials and supporting cost analysis. Cost analysis may be applied to a single treatment or used to compare two or more treatments. Clinical efficacy and cost benefit are best scrutinised and validated by publication in the peer-reviewed literature. True peer review is most effectively achieved 'after publication' by the wider scientific community, i.e., the journal readers. However, initially an editor, usually advised by referees, is asked to make a judgment on a paper's suitability for publication. It follows that medical journals are in a position of power and responsibility. Researchers and editors know publications are currency; effectively they are the equivalent of academic bitcoins. Regarding the paper in this issue by Santema et al., the same authors, in designing a prospective randomised controlled trial (RCT) of the role of hyperbaric oxygen treatment (HBOT) in diabetic wounds, included the name "Damocles" in that trial's title. Readers will perhaps appreciate from my comments below as a referee for the Santema et al. paper, that behind the scenes "the Sword of Damocles" (an allusion to the imminent and ever-present peril faced by those in positions of power) hangs over researchers, treating physician, journal editors and referees alike. Whilst positive about its content, upon reflection, my concern was the anticipated reception of this paper by the journal readership. This is, of course, a matter for the Editor; however, herewith is my reasoning. Further to the body of published work by Bennett et al., and others that has focused attention on the lack of good quality evidence for the use of HBOT for most indications, I think this regrettable state of affairs is now both known and accepted by mainstream healthcare purchasers and providers. I speculate that all these bodies already

Hyperbaric oxygen for carbon monoxide poisoning : a systematic review and critical analysis of the evidence.

PubMed

Buckley, Nicholas A; Isbister, Geoffrey K; Stokes, Barrie; Juurlink, David N

2005-01-01

Poisoning with carbon monoxide (CO) is an important cause of unintentional and intentional injury worldwide. Hyperbaric oxygen (HBO) enhances CO elimination and has been postulated to reduce the incidence of neurological sequelae. These observations have led some clinicians to use HBO for selected patients with CO poisoning, although there is considerable variability in clinical practice. This article assesses the effectiveness of HBO compared with normobaric oxygen (NBO) for the prevention of neurological sequelae in patients with acute CO poisoning. The following databases were searched: MEDLINE (1966 to present), EMBASE (1980 to present), and the Controlled Trials Register of the Cochrane Collaboration, supplemented by a manual review of bibliographies of identified articles and discussion with recognised content experts. All randomised controlled trials involving people acutely poisoned with CO, regardless of severity, were examined. The primary analysis included all trials from which data could be extracted. Sensitivity analysis examined trials with better validity (defined using the validated instrument of Jadad) and those enrolling more severely poisoned patients. Two reviewers independently extracted from each trial, including information on the number of randomised patients, types of participants, the dose and duration of the intervention, and the prevalence of neurological sequelae at follow-up. A pooled odds ratio (OR) for the presence of neurological symptoms at 1-month follow-up was calculated using a random effects model. Bayesian models were also investigated to illustrate the degree of certainty about clinical effectiveness. Eight randomised controlled trials were identified. Two had no evaluable data and were excluded. The remaining trials were of varying quality and two have been published only as abstracts. The severity of CO poisoning varied among trials. At 1-month follow-up after treatment, sequelae possibly related to CO poisoning were

Development of a Minimal-Bulk Oxygen Delivery Product to Enhance Survival During Hemorrhagic Shock/Studies Regarding the Use of Perfluorocarbon- Derived Intravascular Microbubbles from Oxygen Transport

DTIC Science & Technology

2009-07-01

TREATED PIGS A few minu tes after th e Hextend infusion was initiated, th e arterial pr essures started to incr ease gradually as demonstrated in Figure...Until the end of treatment both panels displays SAP (systolic arterial pressure) and DAP (diastolic arterial pr essure ) as mean ± SE, after...toxicity, high pressu re nervous syndrome, work to lerance at pr essure , hyperbaric oxygen treatment for decompression sickness and clinical use

Effectiveness of hyperbaric oxygen for experimental treatment of schistosomiasis mansoni using praziquantel-free and encapsulated into liposomes: assay in adult worms and oviposition.

PubMed

Frezza, Tarsila Ferraz; de Souza, Ana Luiza Ribeiro; Prado, César Corat Ribeiro; de Oliveira, Claudineide Nascimento Fernandes; Gremião, Maria Palmira Daflon; Giorgio, Selma; Dolder, Mary Anne Heidi; Joazeiro, Paulo Pinto; Allegretti, Silmara Marques

2015-10-01

The treatment of schistosomiasis depends on a single drug: praziquantel (PZQ). However, this treatment presents limitations such as low and/or erratic bioavailability that can contribute to cases of tolerance. Improvements to the available drug are urgently needed and studies with a controlled system of drug release, like liposomes, have been gaining prominence. The present study evaluated the activity and synergy between liposomal-praziquantel (lip.PZQ) and hyperbaric oxygen therapy (HBO). Mice received doses of 60 or 100mg/kg PZQ or lip.PZQ, 50 days post-infection, and after the treatment, were exposed to HBO (3 atmosphere absolute - ATA) for 1h. The viability of adult worms and oviposition were analyzed, by necropsy and Kato-Katz examination performed after 15 days of treatment. A concentration of 100mg/kg of lip.PZQ+HBO was more effective (48.0% reduction of worms, 83.3% reduction of eggs/gram of feces) and 100% of the mice had altered of oograms (indicating interruption of oviposition) compared to other treatments and to the Control group (infected and untreated). It is known that PZQ requires participation of the host immune system to complete its antischistosomal activity and that HBO is able to stimulate the immune system. The drug became more available in the body when incorporated into liposomes and, used with HBO, the HBO worked as an adjuvant. This explains the decreases of oviposition and worms recovered form hepatic portal system. Copyright © 2015 Elsevier B.V. All rights reserved.

Fire extinguishment in hypobaric and hyperbaric environments

NASA Technical Reports Server (NTRS)

Kimzey, J. H.

1971-01-01

Work that has been performed to provide information on the effects of various fire extinguishing agents in special atmospheres is discussed. Data used in the development of both equipment and techniques for manned spacecraft and related equipment are discussed. The equipment includes a hypobaric chamber suitable for low pressure use and a hyperbaric chamber for high pressure operation. The effectiveness of agents in weightless environment is also discussed.

Neurobiological insight into hyperbaric hyperoxia.

PubMed

Micarelli, A; Jacobsson, H; Larsson, S A; Jonsson, C; Pagani, M

2013-09-01

Hyperbaric hyperoxia (HBO) is known to modulate aerobic metabolism, vasoreactivity and blood flow in the brain. Nevertheless, mechanisms underlying its therapeutic effects, especially in traumatic brain injury (TBI) and stroke patients, are debated. The present study aimed at investigating regional cerebral blood flow (rCBF) distribution during acute HBO exposure. Regional cerebral blood flow response was investigated in seven healthy subjects exposed to either normobaric normoxia or HBO with ambient pressure/inspired oxygen pressure of 101/21 and 250/250 kPa respectively. After 40 min at the desired pressure, they were injected a perfusion tracer and subsequently underwent brain single photon emission computed tomography. rCBF distribution changes in the whole brain were assessed by Statistical Parametric Mapping. During HBO, an increased relative rCBF distribution was found in sensory-motor, premotor, visual and posterior cingulate cortices as well as in superior frontal gyrus, middle/inferior temporal and angular gyrus and cerebellum, mainly in the dominant hemisphere. During normobaric normoxia, a higher (99m) Tc-HMPAO distribution in the right insula and subcortical structures as well as in bilateral hippocampi and anterior cingulated cortex was found. The present study firstly confirmed the rCBF distribution increase during HBO in sensory-motor and visual cortices, and it showed for the first time a higher perfusion tracer distribution in areas encompassed in dorsal attention system and in default mode network. These findings unfold both the externally directed cognition performance improvement related to the HBO and the internally directed cognition states during resting-state conditions, suggesting possible beneficial effects in TBI and stroke patients. © 2013 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

Effect of Severity, Time to Recompression with Oxygen, and Re-Treatment on Outcome in Forty-Nine Cases of Spinal Cord Decompression Sickness

DTIC Science & Technology

1993-01-01

by physical therapy or no treatment noted that many patients showed gradual recovery, especially if the insult resulted in only mild symptoms (1. 9...GOUP dysba rism, central nervous system, model, hyperbaric oxygen therapy 19. ABSTRACT (Continue on reverse if nece=A iwdýt4~b boknub7 NTIS CRA&I DIDIIC...oxygen therapy The effect of clinical severity and time to recompression with oxygen on outcome from spinal cord DCS is not well defined in the diving

Lower early postnatal oxygen saturation target and risk of ductus arteriosus closure failure.

PubMed

Inomata, Kei; Taniguchi, Shinji; Yonemoto, Hiroki; Inoue, Takeshi; Kawase, Akihiko; Kondo, Yuichi

2016-11-01

Early postnatal hyperoxia is a major risk factor for retinopathy of prematurity (ROP) in extremely premature infants. To reduce the occurrence of ROP, we adopted a lower early postnatal oxygen saturation (SpO 2 ) target range (85-92%) from April 2011. Lower SpO 2 target range, however, may lead to hypoxemia and an increase in the risk of ductus arteriosus (DA) closure failure. The aim of this study was therefore to determine whether a lower SpO 2 target range, during the early postnatal stage, increases the risk of DA closure failure. Infants born at <28 weeks' gestation were enrolled in this study. Oxygen saturation target range during the first postnatal 72 h was 84-100% in study period 1 and 85-92% in period 2. Eighty-two infants were included in period 1, and 61 were included in period 2. The lower oxygen saturation target range increased the occurrence of hypoxemia during the first postnatal 72 h. Prevalence of DA closure failure in period 2 (21%) was significantly higher than that in period 1 (1%). On multivariate logistic regression analysis, the lower oxygen saturation target range was an independent risk factor for DA closure failure. Lower early postnatal oxygen saturation target range increases the risk of DA closure failure. © 2016 Japan Pediatric Society.

Attenuating brain edema, hippocampal oxidative stress, and cognitive dysfunction in rats using hyperbaric oxygen preconditioning during simulated high-altitude exposure.

PubMed

Lin, Hung; Chang, Ching-Ping; Lin, Hung-Jung; Lin, Mao-Tsun; Tsai, Cheng-Chia

2012-05-01

We assessed whether hyperbaric oxygen preconditioning (HBO2P) in rats induced heat shock protein (HSP)-70 and whether HSP-70 antibody (Ab) preconditioning attenuates high altitude exposure (HAE)-induced brain edema, hippocampal oxidative stress, and cognitive dysfunction. Rats were randomly divided into five groups: the non-HBO2P + non-HAE group, the HBO2P + non-HAE group, the non-HBO2P + HAE group, the HBO2P + HAE group, and the HBO2P + HSP-70 Abs + HAE group. The HBO2P groups were given 100% O2 at 2.0 absolute atmospheres for 1 hour per day for 5 consecutive days. The HAE groups were exposed to simulated HAE (9.7% O2 at 0.47 absolute atmospheres of 6,000 m) in a hypobaric chamber for 3 days. Polyclonal rabbit anti-mouse HSP-70-neutralizing Abs were intravenously injected 24 hours before the HAE experiments. Immediately after returning to normal atmosphere, the rats were given cognitive performance tests, overdosed with a general anesthetic, and then their brains were excised en bloc for water content measurements and biochemical evaluation and analysis. Non-HBO2P group rats displayed cognitive deficits, brain edema, and hippocampal oxidative stress (evidenced by increased toxic oxidizing radicals [e.g., nitric oxide metabolites and hydroxyl radicals], increased pro-oxidant enzymes [e.g., malondialdehyde and oxidized glutathione] but decreased antioxidant enzymes [e.g., reduced glutathione, glutathione peroxide, glutathione reductase, and superoxide dismutase]) in HAE. HBO2P induced HSP-70 overexpression in the hippocampus and significantly attenuated HAE-induced brain edema, cognitive deficits, and hippocampal oxidative stress. The beneficial effects of HBO2P were significantly reduced by HSP-70 Ab preconditioning. Our results suggest that high-altitude cerebral edema, cognitive deficit, and hippocampal oxidative stress can be prevented by HSP-70-mediated HBO2P in rats.

Case control study: hyperbaric oxygen treatment of mild traumatic brain injury persistent post-concussion syndrome and post-traumatic stress disorder

PubMed Central

Harch, Paul G.; Andrews, Susan R.; Fogarty, Edward F.; Lucarini, Juliette; Van Meter, Keith W.

2017-01-01

Mild traumatic brain injury (TBI) persistent post-concussion syndrome (PPCS) and post-traumatic stress disorder (PTSD) are epidemic in United States Iraq and Afghanistan War veterans. Treatment of the combined diagnoses is limited. The aim of this study is to assess safety, feasibility, and effectiveness of hyperbaric oxygen treatments (HBOT) for mild TBI PPCS and PTSD. Thirty military subjects aged 18–65 with PPCS with or without PTSD and from one or more blast-induced mild-moderate traumatic brain injuries that were a minimum of 1 year old and occurred after 9/11/2001 were studied. The measures included symptom lists, physical exam, neuropsychological and psychological testing on 29 subjects (1 dropout) and SPECT brain imaging pre and post HBOT. Comparison was made using SPECT imaging on 29 matched Controls. Side effects (30 subjects) experienced due to the HBOT: reversible middle ear barotrauma (n = 6), transient deterioration in symptoms (n = 7), reversible bronchospasm (n = 1), and increased anxiety (n = 2; not related to confinement); unrelated to HBOT: ureterolithiasis (n = 1), chest pain (n = 2). Significant improvement (29 subjects) was seen in neurological exam, symptoms, intelligence quotient, memory, measures of attention, dominant hand motor speed and dexterity, quality of life, general anxiety, PTSD, depression (including reduction in suicidal ideation), and reduced psychoactive medication usage. At 6-month follow-up subjects reported further symptomatic improvement. Compared to Controls the subjects' SPECT was significantly abnormal, significantly improved after 1 and 40 treatments, and became statistically indistinguishable from Controls in 75% of abnormal areas. HBOT was found to be safe and significantly effective for veterans with mild to moderate TBI PPCS with PTSD in all four outcome domains: clinical medicine, neuropsychology, psychology, and SPECT imaging. Veterans also experienced a significant reduction in suicidal ideation and reduction

Case control study: hyperbaric oxygen treatment of mild traumatic brain injury persistent post-concussion syndrome and post-traumatic stress disorder.

PubMed

Harch, Paul G; Andrews, Susan R; Fogarty, Edward F; Lucarini, Juliette; Van Meter, Keith W

2017-01-01

Mild traumatic brain injury (TBI) persistent post-concussion syndrome (PPCS) and post-traumatic stress disorder (PTSD) are epidemic in United States Iraq and Afghanistan War veterans. Treatment of the combined diagnoses is limited. The aim of this study is to assess safety, feasibility, and effectiveness of hyperbaric oxygen treatments (HBOT) for mild TBI PPCS and PTSD. Thirty military subjects aged 18-65 with PPCS with or without PTSD and from one or more blast-induced mild-moderate traumatic brain injuries that were a minimum of 1 year old and occurred after 9/11/2001 were studied. The measures included symptom lists, physical exam, neuropsychological and psychological testing on 29 subjects (1 dropout) and SPECT brain imaging pre and post HBOT. Comparison was made using SPECT imaging on 29 matched Controls. Side effects (30 subjects) experienced due to the HBOT: reversible middle ear barotrauma ( n = 6), transient deterioration in symptoms ( n = 7), reversible bronchospasm ( n = 1), and increased anxiety ( n = 2; not related to confinement); unrelated to HBOT: ureterolithiasis ( n = 1), chest pain ( n = 2). Significant improvement (29 subjects) was seen in neurological exam, symptoms, intelligence quotient, memory, measures of attention, dominant hand motor speed and dexterity, quality of life, general anxiety, PTSD, depression (including reduction in suicidal ideation), and reduced psychoactive medication usage. At 6-month follow-up subjects reported further symptomatic improvement. Compared to Controls the subjects' SPECT was significantly abnormal, significantly improved after 1 and 40 treatments, and became statistically indistinguishable from Controls in 75% of abnormal areas. HBOT was found to be safe and significantly effective for veterans with mild to moderate TBI PPCS with PTSD in all four outcome domains: clinical medicine, neuropsychology, psychology, and SPECT imaging. Veterans also experienced a significant reduction in suicidal ideation and

The compressibility and the capacitance coefficient of helium-oxygen atmospheres.

PubMed

Imbert, G; Dejours, P; Hildwein, G

1982-12-01

The capacitance coefficient beta of an ideal gas mixture depends only on its temperature T, and its value is derived from the ideal gas law (i.e., beta = 1/RT, R being the ideal gas constant). But real gases behave as ideal gases only at low pressures, and this would not be the case in deep diving. High pressures of helium-oxygen are used in human and animal experimental dives (up to 7 or 12 MPa or more, respectively). At such pressures deviations from the ideal gas law cannot be neglected in hyperbaric atmospheres with respect to current accuracy of measuring instruments. As shown both theoretically and experimentally by this study, the non-ideal nature of helium-oxygen has a significant effect on the capacitance coefficient of hyperbaric atmospheres. The theoretical study is based on interaction energy in either homogeneous (He-He and O2-O2) or heterogeneous (He-O2) molecular pairs, and on the virial equation of state for gas mixtures. The experimental study is based on weight determination of samples of known volume of binary helium-oxygen mixtures, which are prepared in well-controlled pressure and temperature conditions. Our experimental results are in good agreement with theoretical predictions. 1) The helium compressibility factor ZHe increases linearly with pressure [ZHe = 1 + 0.0045 P (in MPa) at 30 degrees C]; and 2) in same temperature and pressure conditions (T = 303 K and P = 0.1 to 15 MPa), the same value for Z is valid for a helium-oxygen binary mixture and for pure helium. As derived from the equation of state of real gases, the capacitance coefficient is inversely related to Z (beta = 1/ZRT); therefore, for helium-oxygen mixtures, this coefficient would decrease with increasing pressure. A table is given for theoretical values of helium-oxygen capacitance coefficient, at pressures ranging from 0.1 to 15.0 MPa and at temperatures ranging from 25 degrees C to 37 degrees C.

Effect of circadian rhythm on CNS oxygen toxicity.

NASA Technical Reports Server (NTRS)

Hof, D. G.; Dexter, J. D.; Mengel, C. E.

1971-01-01

The circadian rhythm in susceptibility to oxygen toxicity seizures was investigated by using six groups of 20 male Sprague-Dawley rats (101-196 gm.). The animals were given standard chow, exposed to standard diurnal conditions of light (0700-1900 hr) and dark (1900-0700 hr), and fasted for 15-16 hr prior to exposure to hyperbaric oxygen. The animals were placed in a previously oxygen flushed chamber and raised to 60 psi (gauge) oxygen at a rate of 3 psi/min. Time of exposure started with attainment of 60 psi. End point was first convulsion. The animals' weights were equally distributed within the groups, and the groups were defined by hour of exposure. Time of exposure in minutes prior to seizure was significantly longer in those exposed at 0700-0800 hr and 1000-1100 hr than in four other groups. There was no relationship between animals' weights and time of exposure to seizures. All R values were negative, and the highest R value was -035. These data suggest a definite circadian rhythm in susceptibility to oxygen toxicity seizures.

Optimal dose of hyperbaric bupivacaine 0.5% for unilateral spinal anesthesia during diagnostic knee arthroscopy

PubMed Central

Atef, HM; El-Kasaby, AM; Omera, MA; Badr, MD

2010-01-01

Objective To determine the dose of hyperbaric bupivacaine 0.5% required for unilateral spinal anesthesia during diagnostic knee arthroscopy. Patients and methods This prospective, randomized, clinical study was performed in 80 patients who were assigned to four groups to receive different doses of intrathecal hyperbaric bupivacaine (5 mg, 7.5 mg, 10 mg and 12.5 mg in Groups 1, 2, 3, and 4 respectively). Onset of sensory and motor block, hemodynamic changes, regression of motor block, and incidence of complications were recorded. Results Unilateral sensory block was reported in 90% and 85% of patients in Group 1 and Group 2, respectively, but not in any patient in Group 3 and Group 4. Unilateral motor block (modified Bromage scale 0) was reported in 95% of patients in Group 1, 90% in Group 2, and only 5% in Group 3, while no patient in Group 4 showed unilateral motor block. The time required for regression of motor block (Bromage scale 0) was prolonged with higher doses. The incidence of nausea, vomiting, and urine retention was similar in the study groups. Conclusion Unilateral sensory and motor block can be achieved with doses of 5 mg and 7.5 mg hyperbaric bupivacaine 0.5% with a stable hemodynamic state. However, 7.5 mg of hyperbaric bupivacaine 0.5% was the dose required for adequate unilateral spinal anesthesia. PMID:22915874

[Clinical research of hyperbaric, isobaric, and hypobaric solutions of bupivacaine in continuous spinal anesthesia].

PubMed

Yang, Hong-wei; Bai, Nian-yue; Guo, Qu-lian

2005-02-01

To compare the anesthesia properities of hyperbaric bupivacaine with those of isobaric and hypobaric solutions when administered in the supine position undergoing hip surgery or lower limb surgery using continuous spinal anesthesia. Sixty patients( ASA I approximately III ) scheduled for hip or lower limb surgery were randomly divided into 3 groups with 20 patients in each group: Group A: 0. 375% hyperbaric bupivacaine solutions; Group B :0.375% isobaric bupivacaine solutions; and Group C: 0. 375% hypobaric bupivacaine solutions. The following variables were measured every 2 minutes during the first 30 minutes after the intrathecal injection : the onset time of sensation block, the highest plane of analgesia, the time to reach complete motor blockade, and the plane of analgesia and the extent of lower extremities' movement (modified bromage score, BMS) at different time after the administration. Meanwhile the changes of hemodynamics were recorded. There was no statistical difference among the basic conditions ( P > 0.05). The onset time of sensation block, and the time to reach complete motor blockade, and the time receiving the highest sharp pain sensory block in Group A were significantly shorter than those in Group B and Group C ( P < 0.01 ). The plane of analgesia obtained in the hyperbaric group was significantly higher than in both the isobaric and the hypobaric groups ( P < 0.01). The mean arterial pressure(MAP) , HR in the hyperbaric group decreased significantly after the intrathecal injection( P < 0.05 ). The 0.375% Isobaric bupivacaine used during contiuous spinal anesthesia in the supine position produces a suitable and a more "controllable" anesthesia, but a minimum dosage of 10 approximately 12.5 mg is required to obtain adequate anesthesic conditions with moderate hemodynamic changes and satisfying analgesia effects. Under similar conditions, 0. 375% hyperbaric bupivacaine produces major hemodynamic consequences with high cephalad spread and 0. 375

Solubility of oxygen in a seawater medium in equilibrium with a high-pressure oxy-helium atmosphere.

PubMed

Taylor, C D

1979-06-01

The molar oxygen concentration in a seawater medium in equilibrium with a high-pressure oxygen-helium atmosphere was measured directly in pressurized subsamples, using a modified version of the Winkler oxygen analysis. At a partial pressure of oxygen of 1 atm or less, its concentration in the aqueous phase was adequately described by Henry's Law at total pressures up to 600 atm. This phenomenon, which permits a straightforward determination of dissolved oxygen within hyperbaric systems, resulted from pressure-induced compensatory alterations in the Henry's Law variables rather than from a true obedience to the Ideal Gas Law. If the partial pressure of a gas contributes significantly to the hydrostatic pressure, Henry's Law is no longer adequate for determining its solubility within the compressed medium.

Hyperbaric Oxygen and Ginkgo Biloba Extract Ameliorate Cognitive and Memory Impairment via Nuclear Factor Kappa-B Pathway in Rat Model of Alzheimer's Disease

PubMed Central

Zhang, Li-Da; Ma, Li; Zhang, Li; Dai, Jian-Guo; Chang, Li-Gong; Huang, Pei-Lin; Tian, Xiao-Qiang

2015-01-01

Background: Hyperbaric oxygen (HBO) and Ginkgo biloba extract (e.g., EGB 761) were shown to ameliorate cognitive and memory impairment in Alzheimer's disease (AD). However, the exact mechanism remains elusive. The aim of the present study was to investigate the possible mechanisms of HBO and EGB 761 via the function of nuclear factor kappa-B (NF-κB) pathway. Methods: AD rats were induced by injecting β-amyloid 25–35 into the hippocampus. All animals were divided into six groups: Normal, sham, AD model, HBO (2 atmosphere absolute; 60 min/d), EGB 761 (20 mg·kg−1·d−1), and HBO/EGB 761 groups. Morris water maze tests were used to assess cognitive, and memory capacities of rats; TdT-mediated dUTP Nick-End Labeling staining and Western blotting were used to analyze apoptosis and NF-κB pathway-related proteins in hippocampus tissues. Results: Morris water maze tests revealed that EGB 761 and HBO significantly improved the cognitive and memory ability of AD rats. In addition, the protective effect of combinational therapy (HBO/EGB 761) was superior to either HBO or EGB 761 alone. In line, reduced apoptosis with NF-κB pathway activation was observed in hippocampus neurons treated by HBO and EGB 761. Conclusions: Our results suggested that HBO and EGB 761 improve cognitive and memory capacity in a rat model of AD. The protective effects are associated with the reduced apoptosis with NF-κB pathway activation in hippocampus neurons. PMID:26608991

Ultrastructural characterization and Fourier analysis of fiber cell cytoplasm in the hyperbaric oxygen treated guinea pig lens opacification model.

PubMed

Freel, Christopher D; Gilliland, Kurt O; Mekeel, Harold E; Giblin, Frank J; Costello, M Joseph

2003-04-01

The structural characteristics of differentiated fiber cells in control and hyperbaric oxygen (HBO)-treated guinea pig lenses were examined by transmission electron microscopy (TEM). Emphasis was placed on cell damage, membrane integrity, and cytoplasmic texture. Given the faint gross opacities observed in HBO-treated lenses in previous studies, it was hypothesized that subtle but significant morphological differences due to oxidative damage exist between control and treated animals. Experimental animals received either 70 or 85 treatments with HBO (2.5 atm of 100% O(2) for 2.5 hr, 3 times per week for 5-7 months). All specimens were obtained within 24 hr of death. Freshly cut Vibratome lens sections were fixed and processed for low and high-magnification thin-section TEM analysis. Cytoplasmic texture was analyzed using Fourier and autocorrelation image processing techniques. Low-magnification analysis revealed relatively insignificant differences in general appearance between the fiber cells of the inner fetal and embryonic nuclei in control and HBO-treated guinea pigs. Both groups demonstrated cells of similar morphology with equivalent membrane complexity and homogeneous cytoplasmic texture. Evidence of any major cellular damage or extracellular space debris was not obvious. High-magnification analysis of the cytoplasm of the treated lenses exhibited a mild, yet detectable increase in texture compared with controls and was confirmed by Fourier analysis. Cytoplasmic texture increased in complexity with additional treatments. The absence of major cellular damage in the lenses of HBO-treated animals suggests a less conspicuous source of light scattering. The small changes in cytoplasmic organization observed between treated and control animals may entirely account for the increase in nuclear light scattering observed by slit lamp. The results obtained with this guinea pig/HBO model parallel many of the morphological data associated with human nuclear cataracts. The

Ropivacaine for unilateral spinal anesthesia; hyperbaric or hypobaric?

PubMed

Cantürk, Mehmet; Kılcı, Oya; Ornek, Dilşen; Ozdogan, Levent; Pala, Yasar; Sen, Ozlem; Dikmen, Bayazit

2012-01-01

The aim of this study was to compare the unilaterality of subarachnoid block achieved with hyperbaric and hypobaric ropivacaine. The prospective, randomized trial was conducted in an orthopedics surgical suite. In all, 60 ASA I-III patients scheduled for elective total knee arthroplasty were included in the study. Group Hypo (n=30) received 11.25mg of ropivacaine (7.5mg.mL(-1)) + 2mL of distilled water (density at room temperature was 0.997) and group Hyper (n=30) received 11.25mg of ropivacaine (7.5mg.mL(-1)) + 2mL (5mg.mL(-1)) of dextrose (density at room temperature was 1,015). Patients in the hyperbaric group were positioned with the operated side down and in the 15° Fowler position, versus those in the hypobaric group with the operated side facing up and in the 15° Trendelenburg position. Combined spinal epidural anesthesia was performed midline at the L(3-4) lumbar interspace. Hemodynamic and spinal block parameters, regression time, success of unilateral spinal anesthesia, patient comfort, surgical comfort, surgeon comfort, first analgesic requirement time, and adverse effects were assessed. Time to reach the T10 dermatome level on the operated side was shorter in group Hyper (612.00±163.29s) than in group Hypo (763.63±208.35s) (p<0.05). Time to 2-segment regression of the sensory block level on both the operated and non-operated sides was shorter in group Hypo than in group Hyper. Both hyperbaric and hypobaric ropivacaine (11.25mg) provided adequate and dependable anesthesia for total knee replacement surgery, with a high level of patient and surgeon comfort. Hypobaric local anesthetic solutions provide a high level of unilateral anesthesia, with rapid recovery of both sensory and motor block, and therefore may be preferable in outpatient settings. Copyright © 2012 Elsevier Editora Ltda. All rights reserved.

Phase II Trial of Radiotherapy After Hyperbaric Oxygenation With Multiagent Chemotherapy (Procarbazine, Nimustine, and Vincristine) for High-Grade Gliomas: Long-Term Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ogawa, Kazuhiko, E-mail: kogawa@med.u-ryukyu.ac.jp; Ishiuchi, Shogo; Inoue, Osamu

2012-02-01

Purpose: To analyze the long-term results of a Phase II trial of radiotherapy given immediately after hyperbaric oxygenation (HBO) with multiagent chemotherapy in adults with high-grade gliomas. Methods and Materials: Patients with histologically confirmed high-grade gliomas were administered radiotherapy in daily 2 Gy fractions for 5 consecutive days per week up to a total dose of 60 Gy. Each fraction was administered immediately after HBO, with the time interval from completion of decompression to start of irradiation being less than 15 minutes. Chemotherapy consisting of procarbazine, nimustine, and vincristine and was administered during and after radiotherapy. Results: A total ofmore » 57 patients (39 patients with glioblastoma and 18 patients with Grade 3 gliomas) were enrolled from 2000 to 2006, and the median follow-up of 12 surviving patients was 62.0 months (range, 43.2-119.1 months). All 57 patients were able to complete a total radiotherapy dose of 60 Gy immediately after HBO with one course of concurrent chemotherapy. The median overall survival times in all 57 patients, 39 patients with glioblastoma and 18 patients with Grade 3 gliomas, were 20.2 months, 17.2 months, and 113.4 months, respectively. On multivariate analysis, histologic grade alone was a significant prognostic factor for overall survival (p < 0.001). During treatments, no patients had neutropenic fever or intracranial hemorrhage, and no serious nonhematologic or late toxicities were seen in any of the 57 patients. Conclusions: Radiotherapy delivered immediately after HBO with multiagent chemotherapy was safe, with virtually no late toxicities, and seemed to be effective in patients with high-grade gliomas.« less

A phase I study of low-pressure hyperbaric oxygen therapy for blast-induced post-concussion syndrome and post-traumatic stress disorder.

PubMed

Harch, Paul G; Andrews, Susan R; Fogarty, Edward F; Amen, Daniel; Pezzullo, John C; Lucarini, Juliette; Aubrey, Claire; Taylor, Derek V; Staab, Paul K; Van Meter, Keith W

2012-01-01

This is a preliminary report on the safety and efficacy of 1.5 ATA hyperbaric oxygen therapy (HBOT) in military subjects with chronic blast-induced mild to moderate traumatic brain injury (TBI)/post-concussion syndrome (PCS) and post-traumatic stress disorder (PTSD). Sixteen military subjects received 40 1.5 ATA/60 min HBOT sessions in 30 days. Symptoms, physical and neurological exams, SPECT brain imaging, and neuropsychological and psychological testing were completed before and within 1 week after treatment. Subjects experienced reversible middle ear barotrauma (5), transient deterioration in symptoms (4), and reversible bronchospasm (1); one subject withdrew. Post-treatment testing demonstrated significant improvement in: symptoms, neurological exam, full-scale IQ (+14.8 points; p<0.001), WMS IV Delayed Memory (p=0.026), WMS-IV Working Memory (p=0.003), Stroop Test (p<0.001), TOVA Impulsivity (p=0.041), TOVA Variability (p=0.045), Grooved Pegboard (p=0.028), PCS symptoms (Rivermead PCSQ: p=0.0002), PTSD symptoms (PCL-M: p<0.001), depression (PHQ-9: p<0.001), anxiety (GAD-7: p=0.007), quality of life (MPQoL: p=0.003), and self-report of percent of normal (p<0.001), SPECT coefficient of variation in all white matter and some gray matter ROIs after the first HBOT, and in half of white matter ROIs after 40 HBOT sessions, and SPECT statistical parametric mapping analysis (diffuse improvements in regional cerebral blood flow after 1 and 40 HBOT sessions). Forty 1.5 ATA HBOT sessions in 1 month was safe in a military cohort with chronic blast-induced PCS and PTSD. Significant improvements occurred in symptoms, abnormal physical exam findings, cognitive testing, and quality-of-life measurements, with concomitant significant improvements in SPECT.

[The heart in extreme sports: hyperbaric activity and microgravity].

PubMed

Berrettini, Umberto; Landolfi, Angelo; Patteri, Giovanna

2008-10-01

The study of the cardiovascular and respiratory modifications in extreme environments could be useful for the understanding of the adaptive mechanisms of the body in particular conditions. The knowledge of how different environmental conditions in terms of extreme pressure, temperature and gravity modify the neurovegetative and cardiovascular system could be useful in daily practice for hypobaric and hyperbaric sports.

Welding polarity effects on weld spatters and bead geometry of hyperbaric dry GMAW

NASA Astrophysics Data System (ADS)

Xue, Long; Wu, Jinming; Huang, Junfen; Huang, Jiqiang; Zou, Yong; Liu, Jian

2016-03-01

Welding polarity has influence on welding stability to some extent, but the specific relationship between welding polarity and weld quality has not been found, especially under the hyperbaric environment. Based on a hyperbaric dry welding experiment system, gas metal arc welding(GMAW) experiments with direct current electrode positive(DCEP) and direct current electrode negative(DCEN) operations are carried out under the ambient pressures of 0.1 MPa, 0.4 MPa, 0.7 MPa and 1.0 MPa to find the influence rule of different welding polarities on welding spatters and weld bead geometry. The effects of welding polarities on the weld bead geometry such as the reinforcement, the weld width and the penetration are discussed. The experimental results show that the welding spatters gradually grow in quantity and size for GMAW with DCEP, while GMAW with DCEN can produce fewer spatters comparatively with the increase of the ambient pressure. Compared with DCEP, the welding current and arc voltage waveforms for DCEN is more stable and the distribution of welding current probability density for DCEN is more concentrated under the hyperbaric environment. When the ambient pressure is increased from 0.1 MPa to 1.0 MPa, the effects of welding polarities on the reinforcement, the weld width and the penetration are as follows: an increase of 0.8 mm for the weld reinforcement is produced by GMAW with DCEN and 1.3 mm by GMAW with DCEP, a decrease of 7.2 mm for the weld width is produced by DCEN and 6.1 mm by DCEP; and an increase of 3.9 mm for the penetration is produced by DCEN and 1.9 mm by DCEP. The proposed research indicates that the desirable stability in the welding procedure can be achieved by GMAW with DCEN operation under the hyperbaric environment.

Hyperbaric hydrothermal atomic force microscope

DOEpatents

Knauss, Kevin G.; Boro, Carl O.; Higgins, Steven R.; Eggleston, Carrick M.

2002-01-01

A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

Hyperbaric Hydrothermal Atomic Force Microscope

DOEpatents

Knauss, Kevin G.; Boro, Carl O.; Higgins, Steven R.; Eggleston, Carrick M.

2003-07-01

A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

Multiple Victims of Carbon Monoxide Poisoning in the Aftermath of a Wildfire: A Case Series.

PubMed

Santos, Luís Ramos; Alves-Correia, Magna; Câmara, Margarida; Lélis, Manuela; Caldeira, Carmo; Brazão, Maria Luz; Nóbrega, José Júlio

2018-03-29

Carbon monoxide poisoning may occur in several contexts. Retrospective of 37 carbon monoxide poisoning cases that underwent hyperbaric oxygen during wildfires in Funchal in August 2016. The studied sample included 37 patients, mean age of 38 years, 78% males. Ten were firefighters, four children and two pregnant victims. Neurological symptoms were the most reported. Median carboxyhemoglobin level was 3.7% (IQR 2.7). All received high-flow oxygen from admission to delivery of hyperbaric oxygen. Persistence of symptoms was the main indication for hyperbaric oxygen. Median time to hyperbaric oxygen was 4.8 hours (IQR 9.5), at 2.5 ATA for 90 minutes, without major complications. Discharge in less than 24 hours occurred in 92% of the cases. Thirty days follow-up: five patients presented clinical symptoms of late neurological syndrome; twelve patients were lost to follow-up. Carboxyhemoglobin levels on admission and mean time to hyperbaric oxygen were no different between those who did and did not develop the syndrome at 30 days (p = 0.44 and p = 0.58, respectively). Late neurological syndrome at 30 days occurred in 20% and no new cases were reported at 12 months. Use of hyperbaric oxygen appears to have reduced the incidence of the syndrome. This seems to be the first Portuguese series reporting use of hyperbaric oxygen in carbon monoxide poisoning due to wildfires. The authors intend to alert to the importance of referral of these patients because the indications and benefits of this treatment are well documented. This is especially important given the ever-growing issue of wildfires in Portugal.

New Views on the Early Evolution of Oxygen in the Galaxy

NASA Astrophysics Data System (ADS)

Rebolo, R.; Israelian, G.; García López, R. J.

We have performed a detailed oxygen abundance analysis of 23 metal-poor (-3.0 < [Fe/H] < -0.3) unevolved halo stars and one giant through the OH bands in the near UV, using high-resolution echelle spectra. Oxygen is found to be overabundant with respect to iron in these stars, with the [O/Fe] ratio increasing from 0.6 to 1 between [Fe/H] = -1.5 and -3.0. The behavior of the oxygen overabundance with respect to [Fe/H] is similar to that seen in previous works based on the OI IR triplet data (Abia & Rebolo 1989; Tomkin et al. 1992; Cavallo, Pilachowski, & Rebolo 1997). Contrary to the previously accepted picture, our oxygen abundances, derived from low-excitation OH lines, agree well with those derived from high-excitation lines of the triplet. For nine stars in common with Tomkin et al. we obtain a mean difference of 0.00 plus or minus 0.11dex with respect to the abundances determined from the triplet using the same stellar parameters and model photospheres. Our new results show a smooth extension of the Edvardsson et al.'s (1993) [O/Fe] versus metallicity curve to much lower abundances. The oxygen abundances of unevolved stars when compared with values in the literature for giants of similar metallicity imply that the latter may have suffered a process of oxygen depletion. It appears that unevolved metal-poor stars are better tracers of the early chemical evolution of the Galaxy. The extrapolation of our results to very low metallicities indicates that the ratio of oxygen to iron emerging from the first Type II SNe in the early Galaxy was indeed close to unity. The higher [O/Fe] ratios we find in dwarfs has an impact on the age determination of globular clusters, and suggest that current age estimates have to be reduced by about 1-2 Gyr.

Cervical necrotizing fasciitis: descriptive, retrospective analysis of 59 cases treated at a single center.

PubMed

Elander, Johanna; Nekludov, Michael; Larsson, Agneta; Nordlander, Britt; Eksborg, Staffan; Hydman, Jonas

2016-12-01

To provide retrospective, descriptive information on patients with cervical necrotizing fasciitis treated at a single center during the years 1998-2014, and to evaluate the outcome of a newly introduced treatment strategy. Retrospective analysis of clinical data obtained from medical records. Mortality, pre-morbidity, severity of illness, primary site of infection, type of bacteria, time parameters. The observed 3-month mortality was 6/59 (10 %). The most common initial foci of the infection were pharyngeal, dental or hypopharyngeal. The most common pathogen was Streptococcus milleri bacteria within the Streptococcus anginosus group (66 % of the cases). Using a combined treatment with early surgical debridement combined with hyperbaric oxygen treatment, it is possible to reduce the mortality rate among patients suffering from cervical necrotizing fasciitis, compared to the expected mortality rate and to previous historical reports. Data indicated that early onset of hyperbaric oxygen treatment may have a positive impact on survival rate, but no identifiable factor was found to prognosticate outcome.

The effects of sufentanil added to low-dose hyperbaric bupivacaine in unilateral spinal anaesthesia for outpatients undergoing knee arthroscopy.

PubMed

Sertöz, Nezih; Aysel, İnan; Uyar, Meltem

2014-01-01

The aim of this study is to examine the effects of sufentanil added to low-dose hyperbaric bupivacaine in unilateral spinal anaesthesia for outpatients undergoing knee arthroscopy. Sixty two patients (ASA I-II) aged 20 to 50 who were planning on undergoing a knee arthroscopy were enrolled in this study. Patients were randomly divided into two groups. Unilateral spinal anaesthesia with 1ml 0.5% hyperbaric bupivacaine was administered to Group B (n=33); and unilateral spinal anaesthesia with 0.5ml (2.5µg) sufentanil added to 1ml hyperbaric bupivacaine was administered to Group BS (n=29). There were no statistically significant differences observed between the groups in terms of demographic data, hemodynamic parameters, maximum sensorial, sympathetic and motor block levels, time to motor block resolution, and time of discharge (p>0.05). There were statistically significant differences between the groups in terms of two segments regression time (Group B=52 min., Group BS=59 min.), ambulation time (Group B=147 min., Group BS=157 min.) and urination time (Group B=136 min., Group BS=149 min.) (p<0.05). In this study, no itching was observed in Group B, whereas seven patients in Group BS were observed as having postoperative itching (p<0.05). All patients were successfully given unilateral spinal anaesthesia with sufentanil added to low-dose hyperbaric bupivacaine for an outpatient knee arthroscopy, without affecting the time of discharge. However, for one-day interventions such as arthroscopy, it was concluded that administration of only low-dose hyperbaric bupivacaine was sufficient.

Dexamethasone therapy for preventing delayed encephalopathy after carbon monoxide poisoning.

PubMed

Li, Q; Song, J J; Zhang, H Y; Fu, K; Lan, H B; Deng, Y

2015-01-01

We investigated dexamethasone therapy for preventing delayed encephalopathy after carbon monoxide (CO) poisoning. Eighty healthy male rats were exposed to CO and randomly divided into four groups: hyperbaric oxygen treatment (H), treatment (D), combined hyperbaric and dexamethasone treatment (C), and a control (M) group in which the rats inhaled CO to coma in the hyperbaric oxygen chamber, then were removed without further treatment. Twelve rats were put into the hyperbaric oxygen chamber and treated with air for 60 min (N) group. An eight arm maze was used to evaluate cognitive and memory abilities of these mice. Serum myelin basic protein (MBP) levels were evaluated using ELISA, and magnetic resonance imaging was used to observe brain demyelination and morbidity associated with delayed encephalopathy. A sample of the hippocampus from each group was examined by light microscopy. Cognitive and memory functions decreased in the control group M. Three days after CO poisoning, the serum MBP level of each group increased significantly. On Day 10 after CO poisoning, the MBP levels in groups C and D decreased significantly, but returned to normal on Day 18. MBP levels in the M and H groups were elevated at all time points. Brain MRIs showed significant differences among C, D, H and control M groups. Hematoxylin & eosin staining of the hippocampus showed greater damage in the control M and H groups. Early dexamethasone treatment may be useful for preventing delayed encephalopathy after CO poisoning and may reduce serum MBP levels.

Acquiring the optimal time for hyperbaric therapy in the rat model of CFA induced arthritis.

PubMed

Koo, Sung Tae; Lee, Chang-Hyung; Shin, Yong Il; Ko, Hyun Yoon; Lee, Da Gyo; Jeong, Han-Sol

2014-01-01

We previously published an article about the pressure effect using a rheumatoid animal model. Hyperbaric therapy appears to be beneficial in treating rheumatoid arthritis (RA) by reducing the inflammatory process in an animal model. In this sense, acquiring the optimal pressure-treatment time parameter for RA is important and no optimal hyperbaric therapy time has been suggested up to now. The purpose of our study was to acquire the optimal time for hyperbaric therapy in the RA rat model. Controlled animal study. Following injection of complete Freund's adjuvant (CFA) into one side of the knee joint, 32 rats were randomly assigned to 3 different time groups (1, 3, 5 hours a day) under 1.5 atmospheres absolute (ATA) hyperbaric chamber for 12 days. The pain levels were assessed daily for 2 weeks by weight bearing force (WBF) of the affected limb. In addition, the levels of gelatinase, MMP-2, and MMP-9 expression in the synovial fluids of the knees were analyzed. The reduction of WBF was high at 2 days after injection and then it was spontaneously increased up to 14 days in all 3 groups. There were significant differences of WBF between 5 hours and control during the third through twelfth days, between 3 hours and control during the third through fifth and tenth through twelfth days, and between 3 hours and 5 hours during the third through seventh days (P < 0.05). The MMP-9/MMP-2 ratio increased at 14 days after the CFA injection in all groups compared to the initial findings, however, the 3 hour group showed a smaller MMP-9/MMP-2 ratio than the control group. Although enough samples were used for the study to support our hypothesis, more samples will be needed to raise the validity and reliability. The effect of hyperbaric treatment appears to be dependent upon the elevated therapy time under 1.5 ATA pressure for a short period of time; however, the long-term effects were similar in all pressure groups. Further study will be needed to acquire the optimal pressure

EPR Oximetry for Investigation of Hyperbaric O2 Pre-treatment for Tumor Radiosensitization.

PubMed

Williams, Benjamin B; Hou, Huagang; Coombs, Rachel; Swartz, Harold M

A number of studies have reported benefits associated with the application of hyperbaric oxygen treatment (HBO) delivered immediately prior to radiation therapy. While these studies provide evidence that pre-treatment with HBO may be beneficial, no measurements of intratumoral pO2 were carried out and they do not directly link the apparent benefits to decreased hypoxic fractions at the time of radiation therapy. While there is empirical evidence and some theoretical basis for HBO to enhance radiation therapy, without direct and repeated measurements of its effects on pO2, it is unlikely that the use of HBO can be understood and optimized for clinical applications. In vivo EPR oximetry is a technique uniquely capable of providing repeated direct measurements of pO2 through a non-invasive procedure in both animal models and human patients. In order to evaluate the ability of pretreatment with HBO to elevate tumor pO2, a novel small animal hyperbaric chamber system was constructed that allows simultaneous in vivo EPR oximetry. This chamber can be placed within the EPR magnet and is equipped with a variety of ports for multiplace gas delivery, thermoregulation, delivery of anesthesia, physiologic monitoring, and EPR detection. Initial measurements were performed in a subcutaneous RIF-1 tumor model in C3H/HeJ mice. The mean baseline pO2 value was 6.0 ± 1.2 mmHg (N = 7) and responses to two atmospheres absolute pressure HBO varied considerably across subjects, within tumors, and over time. When an increase in pO2 was observed, the effect was transient in all but one case, with durations lasting from 5 min to over 20 min, and returned to baseline levels during HBO administration. These results indicate that without direct measurements of pO2 in the tissue of interest, it is likely to be difficult to know the effects of HBO on actual tissue pO2.

The Presence of Oxygen in Wound Healing.

PubMed

Kimmel, Howard M; Grant, Anthony; Ditata, James

2016-08-01

Oxygen must be tightly governed in all phases of wound healing to produce viable granulation tissue. This idea of tight regulation has yet to be disputed; however, the role of oxygen at the cellular and molecular levels still is not fully understood as it pertains to its place in healing wounds. In an attempt to better understand the dynamics of oxygen on living tissue and its potential role as a therapy in wound healing, a substantial literature review of the role of oxygen in wound healing was performed and the following key points were extrapolated: 1) During energy metabolism, oxygen is needed for mitochondrial cytochrome oxidase as it produces high-energy phosphates that are needed for many cellular functions, 2) oxygen is also involved in the hydroxylation of proline and lysine into procollagen, which leads to collagen maturation, 3) in angiogenesis, hypoxia is required to start the process of wound healing, but it has been shown that if oxygen is administered it can accelerate and sustain vessel growth, 4) the antimicrobial action of oxygen occurs when nicotinamide adenine dinucleotide phosphate (NADPH)-linked oxygenase acts as a catalyst for the production of reactive oxygen species (ROS), a superoxide ion which kills bacteria, and 5) the level of evidence is moderate for the use of hyperbaric oxygen therapy (HBOT) for diabetic foot ulcers, crush injuries, and soft-tissue infections. The authors hypothesized that HBOT would be beneficial to arterial insufficiency wounds and other ailments, but at this time further study is needed before HBOT would be indicated.

Comparative study of the in vitro activity of various antifungal drugs against Scedosporium spp. in aerobic and hyperbaric atmosphere versus normal atmosphere.

PubMed

Farina, C; Marchesi, G; Passera, M; Diliberto, C; Russello, G

2012-06-01

Scedosporium spp. have been observed with increasing frequency over the last decade in immunocompromised patients and trauma patients. This mould is often multi-drug resistant and its mortality rate remains very high. The primary goal of this study was to obtain data concerning the in vitro susceptibility of 13 Scedosporium strains comparing the in vitro incubation in aerobic versus hyperbaric conditions. Chemosensitivity of thirteen Scedosporium strains was evaluated after a 72h-incubation in a normoxic (21% O2) normobaric (1 ATA) atmosphere versus a hyperoxic (100% O2) hyperbaric (2-3 ATA), and after a re-incubation at room temperature for an additional 72h. All S. apiospermum and S. prolificans strains showed no growth after incubation in hyperbaric hyperoxic atmosphere. However, when plates were then maintained at room temperature in aerobic conditions, growth was systematically observed from 36 to 96h, and Minimal inhibitory concentration (MIC) values were the same obtained after incubation in aerobic conditions. These results suggest impressive in vitro fungistatic activity of the hyperoxic hyperbaric atmosphere, even if its effect is strictly time-dependent. This preliminary in vitro study has potential clinical relevance because it focuses on examining in vitro combination therapy using hyperoxic hyperbaric conditions plus a single antifungal agent, rather than using combinations of different antifungal drugs, to potentially increase the antifungal activity. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Effects of hyperbaric oxygen on symptoms and quality of life among service members with persistent postconcussion symptoms: a randomized clinical trial.

PubMed

Miller, R Scott; Weaver, Lindell K; Bahraini, Nazanin; Churchill, Susan; Price, Robert C; Skiba, Virginia; Caviness, James; Mooney, Scott; Hetzell, Brian; Liu, Jun; Deru, Kayla; Ricciardi, Richard; Fracisco, Susan; Close, Nicole C; Surrett, Gerald W; Bartos, Corinna; Ryan, Margaret; Brenner, Lisa A

2015-01-01

Improvement has been anecdotally observed in patients with persistent postconcussion symptoms (PCS) after mild traumatic brain injury following treatment with hyperbaric oxygen (HBO). The effectiveness of HBO as an adjunctive treatment for PCS is unknown to date. To compare the safety of and to estimate the efficacy for symptomatic outcomes from standard PCS care alone, care supplemented with HBO, or a sham procedure. Multicenter, double-blind, sham-controlled clinical trial of 72 military service members with ongoing symptoms at least 4 months after mild traumatic brain injury enrolled at military hospitals in Colorado, North Carolina, California, and Georgia between April 26, 2011, and August 24, 2012. Assessments occurred before randomization, at the midpoint, and within 1 month after completing the interventions. Routine PCS care was provided in specialized clinics. In addition, participants were randomized 1:1:1 to 40 HBO sessions administered at 1.5 atmospheres absolute (ATA), 40 sham sessions consisting of room air at 1.2 ATA, or no supplemental chamber procedures. The Rivermead Post-Concussion Symptoms Questionnaire (RPQ) served as the primary outcome measure. A change score of at least 2 points on the RPQ-3 subscale (range, 0-12) was defined as clinically significant. Change scores from baseline were calculated for the RPQ-3 and for the total RPQ. Secondary measures included additional patient-reported outcomes and automated neuropsychometric testing. On average, participants had sustained 3 lifetime mild traumatic brain injuries; the most recent occurred 23 months before enrollment. No differences were observed between groups for improvement of at least 2 points on the RPQ-3 subscale (25% in the no intervention group, 52% in the HBO group, and 33% in the sham group; P = .24). Compared with the no intervention group (mean change score, 0.5; 95% CI, -4.8 to 5.8; P = .91), both groups undergoing supplemental chamber procedures showed improvement in symptoms

Hyperbaric pressure does not affect the analgesia produced by nitrous oxide in the mouse.

PubMed

Cohen, P J

1989-01-01

Hydrostatic pressure antagonizes some, but not all, of the phenomena associated with general anaesthesia. For example, while unconsciousness produced by general anaesthesia in a wide variety of species is reversed by compression, anaesthetic-induced inhibition of synaptic transmission is potentiated by application of pressure. To date, the effect of pressure on analgesia has not been evaluated. In this study, hyperbaric pressure of 75 ata did not antagonize analgesia which had been produced by exposure of mice to 1.2 ata of nitrous oxide. However, the same hyperbaric pressure restored righting in animals which had been anesthetized with 1.5 ata of nitrous oxide. These data add to the suggestion that the multiple effects of general anaesthetics may be mediated at different loci.

Increased Efficacy of Antivenom Combined with Hyperbaric Oxygen on Deinagkistrodon acutus Envenomation in Adult Rats

PubMed Central

Li, Mo; Xie, Zhi-Hui; Yu, An-Yong; He, Dong-Po

2018-01-01

Background: Snakebites are a neglected threat to global human health with a high morbidity rate. The present study explored the efficacy of antivenom with hyperbaric oxygen (HBO) intervention on snakebites, which could provide the experimental basis for clinical adjuvant therapy. Methods: Male Sprague–Dawley rats (n = 96) were randomized into four groups: the poison model was established by injecting Deinagkistrodon acutus (D. acutus) venom (0.8 LD50) via the caudal vein; the antivenom group was injected immediately with specific antivenom via the caudal vein after successful establishment of the envenomation model; and the antivenom + HBO group was exposed to HBO environment for 1 h once at predetermined periods of 0 h, 4 h, 12 h, and 23 h after antivenin administration. Each HBO time point had six rats; the control group was left untreated. The rats in the experimental group were euthanized at the corresponding time points after HBO therapy, and brain tissue and blood were harvested immediately. Hematoxylin and eosin (H&E) staining was used to investigate the pathological changes in the rat brain. Immunohistochemistry (IHC), real-time polymerase chain reaction (PCR), and Western blotting were used to detect the expression of Nestin mRNA and protein in the subventricular zone (SVZ) of the brain. The levels of coagulation function (prothrombin time, activated partial thromboplastin time [APTT], and fibrinogen) and oxidation/antioxidation index (malondialdehyde [MDA] and superoxide dismutase [SOD]) were analyzed. Data were analyzed using one-way analysis of variance. Results: The brain tissue from rats in the poison model was observed for pathological changes using H&E staining. Tissues showed edema, decreased cell number, and disordered arrangement in the SVZ in the snake venom group. The antivenom − HBO intervention significantly alleviated these observations and was more prominent in the antivenom + HBO group. The serum levels of SOD and MDA in the snake

Effects of hyperbaric oxygen therapy on depression and anxiety in the patients with incomplete spinal cord injury (a STROBE-compliant article).

PubMed

Feng, Juan-Juan; Li, You-Hui

2017-07-01

Little research has been done on the effects of hyperbaric oxygen (HBO) on depression and anxiety after spinal cord injury (SCI). The aim of this study was to investigate the effects of HBO on psychological problems and never function, especially on depression and anxiety in the patients with incomplete SCI (ISCI).Sixty patients with ISCI combined with depression and anxiety were randomly divided into HBO group (20 cases), psychotherapy group (20 cases), and conventional rehabilitation control group (20 cases). All patients received routine rehabilitation therapy. However, in HBO group and psychotherapy group, patients also received HBO and psychotherapy, respectively. These therapies lasted for a total of 8 weeks (once a day and 6 days per week). Before and after 8 weeks of treatment, depression and anxiety, nerve function, and activities of daily living were, respectively, evaluated according to Hamilton Depression (HAMD) scale, Hamilton Anxiety (HAMA) scale, American Spinal Injury Association score, and functional independence measure score in all patients.After 8 weeks of treatment, HAMD score was significantly lower in both HBO group and psychotherapy group than in control group (all P < .05), but there was no statistical difference in HAMD score between HBO group and psychotherapy group (P > .05). HAMA score was significantly lower in HBO group than in control group (P < .05), but there was no statistical difference in HAMA score between HBO group and psychotherapy group, and between psychotherapy group and control group (all P > .05). After 8 weeks of treatment, American Spinal Injury Association and functional independence measure scores were significantly higher in HBO group than in both psychological and control groups, and also higher in psychotherapy group than in control group (all P < .05).The effects of HBO on depression and anxiety are similar to that of psychotherapy. HBO can significantly improve nerve function and activities

Atmospheric oxygen levels affect mudskipper terrestrial performance: implications for early tetrapods.

PubMed

Jew, Corey J; Wegner, Nicholas C; Yanagitsuru, Yuzo; Tresguerres, Martin; Graham, Jeffrey B

2013-08-01

The Japanese mudskipper (Periophthalmus modestus), an amphibious fish that possesses many respiratory and locomotive specializations for sojourns onto land, was used as a model to study how changing atmospheric oxygen concentrations during the middle and late Paleozoic Era (400-250 million years ago) may have influenced the emergence and subsequent radiation of the first tetrapods. The effects of different atmospheric oxygen concentrations (hyperoxia = 35%, normoxia = 21%, and hypoxia = 7% O2) on terrestrial performance were tested during exercise on a terrestrial treadmill and during recovery from exhaustive exercise. Endurance and elevated post-exercise oxygen consumption (EPOC; the immediate O2 debt repaid post-exercise) correlated with atmospheric oxygen concentration indicating that when additional oxygen is available P. modestus can increase oxygen utilization both during and following exercise. The time required post-exercise for mudskippers to return to a resting metabolic rate did not differ between treatments. However, in normoxia, oxygen consumption increased above hyperoxic values 13-20 h post-exercise suggesting a delayed repayment of the incurred oxygen debt. Finally, following exercise, ventilatory movements associated with buccopharyngeal aerial respiration returned to their rest-like pattern more quickly at higher concentrations of oxygen. Taken together, the results of this study show that P. modestus can exercise longer and recover quicker under higher oxygen concentrations. Similarities between P. modestus and early tetrapods suggest that increasing atmospheric oxygen levels during the middle and late Paleozoic allowed for elevated aerobic capacity and improved terrestrial performance, and likely led to an accelerated diversification and expansion of vertebrate life into the terrestrial biosphere.

Hyperbaric Oxygen, Vasculogenic Stem Cells, and Wound Healing

PubMed Central

Fosen, Katina M.

2014-01-01

Abstract Significance: Oxidative stress is recognized as playing a role in stem cell mobilization from peripheral sites and also cell function. Recent Advances: This review focuses on the impact of hyperoxia on vasculogenic stem cells and elements of wound healing. Critical Issues: Components of the wound-healing process in which oxidative stress has a positive impact on the various cells involved in wound healing are highlighted. A slightly different view of wound-healing physiology is adopted by departing from the often used notion of sequential stages: hemostatic, inflammatory, proliferative, and remodeling and instead organizes the cascade of wound healing as overlapping events or waves pertaining to reactive oxygen species, lactate, and nitric oxide. This was done because hyperoxia has effects of a number of cell signaling events that converge to influence cell recruitment/chemotaxis and gene regulation/protein synthesis responses which mediate wound healing. Future Directions: Our alternative perspective of the stages of wound healing eases recognition of the multiple sites where oxidative stress has an impact on wound healing. This aids the focus on mechanistic events and the interplay among various cell types and biochemical processes. It also highlights the areas where additional research is needed. Antioxid. Redox Signal. 21, 1634–1647. PMID:24730726

In-Vitro Performance of the Enlite Sensor in Various Glucose Concentrations during Hypobaric and Hyperbaric Conditions

PubMed Central

Adolfsson, Peter; Örnhagen, Hans; Eriksson, Bengt M.; Gautham, Raghavendhar; Jendle, Johan

2012-01-01

Background There is a need for reliable methods of glucose measurement in different environmental conditions. The objective of this in vitro study was to evaluate the performance of the Enlite® Sensor when connected to either the iPro™ Continuous Glucose Monitor recording device or the Guardian® REAL-Time transmitting device, in hypobaric and hyperbaric conditions. Methods Sixteen sensors connected to eight iPro devices and eight Guardian REAL-Time devices were immersed in three beakers containing separate glucose concentrations: 52, 88, and 207 mg/dl (2.9, 4.9, and 11.3 mmol/liter). Two different pressure tests were conducted: a hypobaric test, corresponding to maximum 18000 ft/5500 m height, and a hyperbaric test, corresponding to maximum 100 ft/30 m depth. The linearity of the sensor signals in the different conditions was evaluated. Results The sensors worked continuously, and the sensor signals were collected without interruption at all pressures tested. When comparing the input signals for glucose (ISIGs) and the different glucose concentrations during altered pressure, linearity (R2) of 0.98 was found. During the hypobaric test, significant differences (p < .005) were seen when comparing the ISIGs during varying pressure at two of the glucose concentrations (52 and 207 mg/dl), whereas no difference was seen at the 88 mg/dl glucose concentration. During the hyperbaric test, no differences were found. Conclusions The Enlite Sensors connected to either the iPro or the Guardian REAL-Time device provided values continuously. In hyperbaric conditions, no significant differences were seen during changes in ambient pressure; however, during hypobaric conditions, the ISIG was significantly different in the low and high glucose concentrations. PMID:23294783

In-vitro performance of the Enlite Sensor in various glucose concentrations during hypobaric and hyperbaric conditions.

PubMed

Adolfsson, Peter; Ornhagen, Hans; Eriksson, Bengt M; Gautham, Raghavendhar; Jendle, Johan

2012-11-01

There is a need for reliable methods of glucose measurement in different environmental conditions. The objective of this in vitro study was to evaluate the performance of the Enlite® Sensor when connected to either the iPro™ Continuous Glucose Monitor recording device or the Guardian® REAL-Time transmitting device, in hypobaric and hyperbaric conditions. Sixteen sensors connected to eight iPro devices and eight Guardian REAL-Time devices were immersed in three beakers containing separate glucose concentrations: 52, 88, and 207 mg/dl (2.9, 4.9, and 11.3 mmol/liter). Two different pressure tests were conducted: a hypobaric test, corresponding to maximum 18000 ft/5500 m height, and a hyperbaric test, corresponding to maximum 100 ft/30 m depth. The linearity of the sensor signals in the different conditions was evaluated. The sensors worked continuously, and the sensor signals were collected without interruption at all pressures tested. When comparing the input signals for glucose (ISIGs) and the different glucose concentrations during altered pressure, linearity (R(2)) of 0.98 was found. During the hypobaric test, significant differences (p < .005) were seen when comparing the ISIGs during varying pressure at two of the glucose concentrations (52 and 207 mg/dl), whereas no difference was seen at the 88 mg/dl glucose concentration. During the hyperbaric test, no differences were found. The Enlite Sensors connected to either the iPro or the Guardian REAL-Time device provided values continuously. In hyperbaric conditions, no significant differences were seen during changes in ambient pressure; however, during hypobaric conditions, the ISIG was significantly different in the low and high glucose concentrations. © 2012 Diabetes Technology Society.

A randomized controlled study comparing intrathecal hyperbaric bupivacaine-fentanyl mixture and isobaric bupivacaine-fentanyl mixture in common urological procedures

PubMed Central

Upadya, Madhusudan; Neeta, S; Manissery, Jesni Joseph; Kuriakose, Nigel; Singh, Rakesh Raushan

2016-01-01

Background and Aims: Bupivacaine is available in isobaric and hyperbaric forms for intrathecal use and opioids are used as additives to modify their effects. The aim of this study was to compare the efficacy and haemodynamic effect of intrathecal isobaric bupivacaine-fentanyl mixture and hyperbaric bupivacaine-fentanyl mixture in common urological procedures. Methods: One hundred American Society of Anesthesiologists physical status 1 and 2 patients undergoing urological procedures were randomized into two groups. Group 1 received 3 ml of 0.5% isobaric bupivacaine with 25 μg fentanyl while Group 2 received 3 ml of 0.5% hyperbaric bupivacaine with 25 μg fentanyl. The parameters measured include heart rate, blood pressure, respiratory rate, onset and duration of motor and sensory blockade. Student's unpaired t-test and the χ2 test were used to analyse the results, using the SPSS version 11.5 software. Results: The haemodynamic stability was better with isobaric bupivacaine fentanyl mixture (Group 1) than with hyperbaric bupivacaine fentanyl mixture (Group 2). The mean onset time in Group 1 for both sensory block (4 min) and motor block (5 min) was longer compared with Group 2. The duration of sensory block (127.8 ± 38.64 min) and motor block (170.4 ± 27.8 min) was less with isobaric bupivacaine group compared with hyperbaric bupivacaine group (sensory blockade 185.4 ± 16.08 min and motor blockade 201.6 ± 14.28 min). Seventy percent of patients in Group 2 had maximum sensory block level of T6 whereas it was 53% in Group 1. More patients in Group 1 required sedation compared to Group 2. Conclusion: Isobaric bupivacaine fentanyl mixture was found to provide adequate anaesthesia with minimal incidence of haemodynamic instability. PMID:26962255

Oxygen reservoirs in the early solar nebula inferred from an Allende CAI.

PubMed

Young, E D; Russell, S S

1998-10-16

Ultraviolet laser microprobe analyses of a calcium-aluminum-rich inclusion (CAI) from the Allende meteorite suggest that a line with a slope of exactly 1.00 on a plot of delta (17)O against delta (18)O represents the primitive oxygen isotope reservoir of the early solar nebula. Most meteorites are enriched in (17)O and (18)O relative to this line, and their oxygen isotope ratios can be explained by mass fractionation or isotope exchange initiating from the primitive reservoir. These data establish a link between the oxygen isotopic composition of the abundant ordinary chondrites and the primitive (16)O-rich component of CAIs.

Oxygen reservoirs in the early solar nebula inferred from an allende CAI

PubMed

Young; Russell

1998-10-16

Ultraviolet laser microprobe analyses of a calcium-aluminum-rich inclusion (CAI) from the Allende meteorite suggest that a line with a slope of exactly 1.00 on a plot of delta17O against delta18O represents the primitive oxygen isotope reservoir of the early solar nebula. Most meteorites are enriched in 17O and 18O relative to this line, and their oxygen isotope ratios can be explained by mass fractionation or isotope exchange initiating from the primitive reservoir. These data establish a link between the oxygen isotopic composition of the abundant ordinary chondrites and the primitive 16O-rich component of CAIs.

Enhanced control of Bacillus subtilis endospores development by hyperbaric storage at variable/uncontrolled room temperature compared to refrigeration.

PubMed

Pinto, Carlos A; Santos, Mauro D; Fidalgo, Liliana G; Delgadillo, Ivonne; Saraiva, Jorge A

2018-09-01

The effect of hyperbaric storage on Bacillus subtilis endospores, as a new food preservation methodology with potential to replace the conventional refrigeration processes, was assessed and compared to refrigeration. To do so, three different matrices (McIlvaine buffer, carrot juice and brain-heart infusion broth, BHI-broth) were inoculated with B. subtilis endospores and stored at 25, 50 and 100 MPa at variable/uncontrolled room temperature (18-23 °C), under refrigeration (4 °C), and room temperature at atmospheric pressure (0.1 MPa), up to 60 days. Two different quantification procedures were performed to assay both vegetative and endospores (unheated samples) and endospores (heated samples), to assess germination under pressure. The results showed that hyperbaric storage yielded pronounced endospore loads reductions in carrot juice and BHI-broth at 50 and 100 MPa, while in McIlvaine buffer, lower endospore loads reductions were observed. At 25 MPa, the endospores germinated and outgrew in carrot juice. Under refrigeration conditions, both carrot juice and BHI-broth underwent endospore germination and outgrowth after 60 and 9 days of storage, respectively, while in McIlvaine buffer there were no endospore outgrowth. These results suggest that hyperbaric storage at room temperature might not only be a feasible preservation procedure regarding endospores, but also that the food product (matrix characteristics) seems to influence the microbial inactivation that occurs during hyperbaric storage. Copyright © 2018 Elsevier Ltd. All rights reserved.

Reinforcement of spinal anesthesia by epidural injection of saline: a comparison of hyperbaric and isobaric tetracaine.

PubMed

Yamazaki, Y; Mimura, M; Hazama, K; Namiki, A

2000-04-25

An epidural injection of saline was reported to extend spinal anesthesia because of a volume effect. The aim of this study was to evaluate the influence of the baricity of spinal local anesthetics upon the extension of spinal anesthesia by epidural injection of saline. Forty patients undergoing elective lower-limb surgery were randomly allocated to four groups of 10 patients each. Group A received no epidural injection after the spinal administration of hyperbaric tetracaine (dissolved in 10% glucose). Group B received an epidural injection of 8 ml of physiological saline 20 min after spinal hyperbaric tetracaine. Group C received no epidural injection after spinal isobaric tetracaine (dissolved in physiological saline). Group D received an epidural injection of 8 ml of saline 20 min after spinal isobaric tetracaine. The level of analgesia was examined by the pinprick method at 5-min intervals. The levels of analgesia 20 min after spinal anesthesia were significantly higher in hyperbaric groups than in isobaric groups [T5 (T2-L2) vs. T7 (T3-12)]. After epidural injection of saline, the levels of analgesia in groups B and D were significantly higher than in groups A and C. The segmental increases after epidural saline injection were 2 (0-3) in group B and 2 (1-7) in group D. Sensation in the sacral area remained 20 min after spinal block in one patient in group D; however, it disappeared after epidural saline injection. In this study, 8 ml of epidural saline extended spinal analgesia. However, there was no difference between the augmenting effect in isobaric and hyperbaric spinal anesthesia. We conclude that the reinforcement of spinal anesthesia by epidural injection of saline is not affected by the baricity of the spinal anesthetic solution used.

INITIAL OBSERVATIONS ON THE EFFECT OF HYPOBARIC AND HYPERBARIC PRESSURE ON CELL PERMEABILITY.

DTIC Science & Technology

erythrocytes in hypotonic saline at hypobaric and hyperbaric pressures showed an increase and decrease, respectively, in the extent of hemolysis when...resulted in an apparent alteration in the mechanics of solvent exchange or cell permeability, or both. Comparison of the relative hemolysis of human

Early Oxygen-Utilization and Brain Activity in Preterm Infants

PubMed Central

de Vries, Linda S.; Groenendaal, Floris; Toet, Mona C.; Lemmers, Petra M. A.; Vosse van de, Renè E.; van Bel, Frank; Benders, Manon J. N. L.

2015-01-01

The combined monitoring of oxygen supply and delivery using Near-InfraRed spectroscopy (NIRS) and cerebral activity using amplitude-integrated EEG (aEEG) could yield new insights into brain metabolism and detect potentially vulnerable conditions soon after birth. The relationship between NIRS and quantitative aEEG/EEG parameters has not yet been investigated. Our aim was to study the association between oxygen utilization during the first 6 h after birth and simultaneously continuously monitored brain activity measured by aEEG/EEG. Forty-four hemodynamically stable babies with a GA < 28 weeks, with good quality NIRS and aEEG/EEG data available and who did not receive morphine were included in the study. aEEG and NIRS monitoring started at NICU admission. The relation between regional cerebral oxygen saturation (rScO2) and cerebral fractional tissue oxygen extraction (cFTOE), and quantitative measurements of brain activity such as number of spontaneous activity transients (SAT) per minute (SAT rate), the interval in seconds (i.e. time) between SATs (ISI) and the minimum amplitude of the EEG in μV (min aEEG) were evaluated. rScO2 was negatively associated with SAT rate (β=-3.45 [CI=-5.76- -1.15], p=0.004) and positively associated with ISI (β=1.45 [CI=0.44-2.45], p=0.006). cFTOE was positively associated with SAT rate (β=0.034 [CI=0.009-0.059], p=0.008) and negatively associated with ISI (β=-0.015 [CI=-0.026- -0.004], p=0.007). Oxygen delivery and utilization, as indicated by rScO2 and cFTOE, are directly related to functional brain activity, expressed by SAT rate and ISI during the first hours after birth, showing an increase in oxygen extraction in preterm infants with increased early electro-cerebral activity. NIRS monitored oxygenation may be a useful biomarker of brain vulnerability in high-risk infants. PMID:25965343

Hyperbaric vs. isobaric bupivacaine for spinal anaesthesia for elective caesarean section: a Cochrane systematic review.

PubMed

Sng, B L; Han, N L R; Leong, W L; Sultana, R; Siddiqui, F J; Assam, P N; Chan, E S; Tan, K H; Sia, A T

2018-04-01

Both isobaric and hyperbaric bupivacaine have been used for spinal anaesthesia for elective caesarean section, but it is not clear if one is better than the other. The primary objective of this systematic review was to determine the effectiveness and safety of hyperbaric bupivacaine compared with isobaric bupivacaine administered during spinal anaesthesia for elective caesarean section. We included 10 studies with 614 subjects in the analysis. There was no evidence of differences either in the risk of conversion to general anaesthesia, with a relative risk (95%CI) of 0.33 (0.09-1.17) (very low quality of evidence), or in the need for supplemental analgesia, the relative risk (95%CI) being 0.61 (0.26-1.41) (very low quality of evidence). There was also no evidence of a difference in the use of ephedrine, the amount of ephedrine used, nausea and vomiting, or headache. Hyperbaric bupivacaine took less time to reach a sensory block height of T4, with a mean difference (95%CI) of -1.06 min (-1.80 to -0.31). Due to the rarity of some outcomes, dose variability, use of adjuvant drugs and spinal technique used, future clinical trials should look into using adequate sample size to investigate the primary outcome of the need for supplemental analgesia. © 2017 The Association of Anaesthetists of Great Britain and Ireland.

Hyperbaric oxygen attenuates neuropathic pain and reverses inflammatory signaling likely via the Kindlin-1/Wnt-10a signaling pathway in the chronic pain injury model in rats.

PubMed

Zhao, Baisong; Pan, Yongying; Xu, Haiping; Song, Xingrong

2017-12-01

Hyperbaric oxygen (HBO) therapy is proven to attenuate neuropathic pain in rodents. The goal of the present study was to determine the potential involvement of the Kindlin-1/Wnt-10a signaling pathway during astrocyte activation and inflammation in a rodent model of neuropathic pain. Rats were assigned into sham operation, chronic constriction injury (CCI), and CCI + HBO treatment groups. Neuropathic pain developed in rats following CCI of the sciatic nerve. Rats in the CCI + HBO group received HBO treatment for five consecutive days beginning on postoperative day 1. The mechanical withdrawal threshold (MWT) and the thermal withdrawal latency (TWL) tests were performed to determine mechanical and heat hypersensitivity of animals, respectively. Kindlin-1, Wnt-10a and β-catenin protein expression was examined by immunohistochemistry and Western blot analysis. Expression of tumor necrosis factor (TNF)-α was also determined by ELISA. Our findings demonstrated that HBO treatment significantly suppressed mechanical and thermal hypersensitivity in the CCI neuropathic pain model in rats. HBO therapy significantly reversed the up-regulation of Kindlin-1 in dorsal root ganglia (DRG), spinal cord, and hippocampus of CCI rats. CCI-induced astrocyte activation and increased levels of TNF-α were efficiently reversed by HBO (P < 0.05 vs. CCI). HBO also reversed Wnt-10a up-regulation induced by CCI in the DRG, spinal cord, and hippocampus (P < 0.05 vs. CCI). Our findings demonstrate that HBO attenuated CCI-induced rat neuropathic pain and inflammatory responses, possibly through regulation of the Kindlin-1/Wnt-10a signaling pathway.

Using Triple Oxygen Isotope Analyses of Biogenic Carbonate to Reconstruct Early Triassic Ocean Oxygen Isotopic Values and Temperatures

NASA Astrophysics Data System (ADS)

Gibbons, J. A.; Sharp, Z. D.; Atudorei, V.

2017-12-01

The calcite-water triple oxygen isotope fractionation is used to determine isotopic equilibrium and ancient ocean oxygen isotopic values and temperatures. Unlike conventional δ18O analysis where the formation water's isotopic value is assumed, paired δ17O-δ18O measurements allow for the water's isotopic composition to be calculated because there is only one unique solution for equilibrium fractionation using Δ17O-δ18O values (where Δ17O=δ17O-0.528δ18O). To a first approximation, the calcite-water equilibrium fractionation factor, θ (where θ=ln17α/ln18α), varies with temperature by 0.00001/°. The calcite-water equilibrium fractionation line was determined at two temperatures, 30° and 0°, by using modern carbonate samples that formed in ocean water with a δ18O value of 0‰. The θ values for the 30° and 0° samples are 0.52515 and 0.52486, respectively. Oxygen values were measured using complete fluorination in nickel tubes with BrF5 as the reaction reagent. We calibrated all oxygen values to the SMOW-SLAP scale by measuring SMOW, SLAP, San Carlos olivine, NBS-18, NBS-19, and PDB. The triple oxygen isotope calcite-water equilibrium fractionation line was applied to well preserved Early Triassic ammonite shells from the Western United States. Based on paired δ17O-δ18O measurements, the samples did not form in equilibrium with an ice-free ocean with an oxygen isotopic value of -1‰ or the modern ocean value of 0‰. Assuming the calcite is still primary and formed in equilibrium with the ocean water, our data indicate that the δ18O value of the ocean in the early Triassic was 3-5‰ lower than modern. Samples from the Smithian thermal maximum formed in water 10° warmer than samples from after the thermal maximum. Paired δ17O-δ18O measurements of pristine ancient carbonates may provide a better understanding of past ocean conditions during climate change events.

Optic neuropathy following an altitude exposure.

PubMed

Steigleman, Allan; Butler, Frank; Chhoeu, Austin; O'Malley, Timothy; Bower, Eric; Giebner, Stephen

2003-09-01

This case report describes a 20-yr-old man who presented with retro-orbital pain and blurred vision in his left eye 3 wk after an altitude exposure in a hypobaric chamber. He was found to have significant deficits in color vision and visual fields consistent with an optic neuropathy in his left eye. The patient was diagnosed with decompression sickness and treated with hyperbaric oxygen with a U.S. Navy Treatment Table VI. All signs and symptoms resolved with a single hyperbaric oxygen treatment but recurred. A head MRI revealed a left frontoethmoid sinus opacity. A concomitant sinusitis was diagnosed. The patient had full resolution of symptoms after a total of four hyperbaric oxygen treatments and antibiotic therapy at 6-wk follow-up. Although a para-infectious etiology for this patient's optic neuropathy cannot be excluded, his history of altitude exposure and significant, rapid response to hyperbaric oxygen treatment strongly implies decompression sickness in this case.

Tracking Early Jurassic marine (de)oxygenation

NASA Astrophysics Data System (ADS)

Them, T. R., II; Caruthers, A. H.; Gill, B. C.; Gröcke, D. R.; Marroquín, S. M.; Owens, J. D.

2017-12-01

It has been suggested that the carbon cycle was perturbed during the Toarcian OAE (T-OAE) as observed in the carbon isotope record, and more recently other elemental cycles (e.g., Hg, Mo, Os, S). The most widely accepted hypothesis focuses on the emplacement of the Karoo-Ferrar large igneous province, outgassing of greenhouse gases, and subsequent feedbacks in the Earth system, which caused severe environmental change and biological turnover. Feedbacks to elevated atmospheric pCO2 include enhanced weathering rates, dissociation of methane clathrates, increased terrestrial methanogenesis, and widespread marine anoxia. The sequence of events related to the development and duration of marine anoxia are not well constrained for this time interval due to a lack of open-ocean geochemical records. In order to reconstruct the timing of marine deoxygenation during the Early Jurassic T-OAE, we have utilized thallium isotopes, a novel geochemical proxy from multiple anoxic basins in North America and Germany. Three sites representing a basin transect from the Western Canada Sedimentary Basin, and one site from the South German Basin, were chosen to reconstruct the thallium isotopic composition (ɛ205Tl) of the ocean. The ɛ205Tl composition of sediments deposited under anoxic and euxinic water columns records the global seawater ɛ205Tl composition, a function of the amount of manganese oxides that are precipitated. Increased geographic extent of marine anoxia will cause a decrease in manganese oxide precipitation and perturb the thallium system. Importantly, the inputs of thallium are nearly identical, thus changes in these fluxes cannot drive the observed perturbation. Our new Early Jurassic ɛ205Tl records suggest that the onset of marine deoxygenation occurred concurrently with Karoo-Ferrar magmatism in the late Pliensbachian and continued until after the T-OAE. These new data support a Karoo-Ferrar trigger of the T-OAE. However, thallium isotopes also suggest that

Hyperbaric storage of melon juice at and above room temperature and comparison with storage at atmospheric pressure and refrigeration.

PubMed

Queirós, Rui P; Santos, Mauro D; Fidalgo, Liliana G; Mota, Maria J; Lopes, Rita P; Inácio, Rita S; Delgadillo, Ivonne; Saraiva, Jorge A

2014-03-15

Hyperbaric storage (8h) of melon juice (a highly perishable food) at 25, 30 and 37°C, under pressure at 25-150 MPa was compared with atmospheric pressure storage (0.1 MPa) at the same temperatures and under refrigeration (4°C). Comparatively to the refrigerated condition, hyperbaric storage at 50/75 MPa resulted in similar or lower microbial counts (total aerobic mesophiles, enterobacteriaceae, and yeasts/moulds) while at 100/150 MPa, the counts were lower for all the tested temperatures, indicating in the latter case, in addition to microbial growth inhibition, a microbial inactivation effect. At 25 MPa no microbial inhibition was observed. Physicochemical parameters of all samples stored under pressure (pH, titratable acidity, total soluble solids, browning degree and cloudiness) did not show a clear variation trend with pressure, being the results globally similar to refrigeration storage. These results show the potential of hyperbaric storage, at and above room temperature and with potential energy savings, comparatively to refrigeration. Copyright © 2013 Elsevier Ltd. All rights reserved.

[Hyperbaric oxygen therapy adjunctive to surgical debridement in management of Fournier's gangrene: usefulness of a severity index score in predicting disease gravity and patient survival].

PubMed

Janane, A; Hajji, F; Ismail, T O; Chafiqui, J; Ghadouane, M; Ameur, A; Abbar, M; Albouzidi, A

2011-06-01

Hyperbaric oxygen therapy (HBOT) concomitant to surgery has been reported to reduce Fournier's gangrene (FG) mortality compared to exclusive surgical debridement. Most report from centers with relatively few patients using only surgical procedure. To assess efficiency of aggressive debridement with adjunctive HBOT. To evaluate Fournier's gangrene severity score index (FGSI) predictive value. 70 Fournier's gangrene (FG) treated by surgical debridement and HBOT. Data were evaluated physical examination findings, admission and final laboratory tests, surgical debridement extent, and antibiotic used. Patients had adjunctive (HBOT). FGSI, developed to assign a score describing the acuity of disease, was used. This index presents patients' vital signs, metabolic parameters (sodium, potassium, creatinine, and bicarbonate levels, and white blood cell count) and computes a score relating to the severity of disease at that time. Data were assessed according to whether the patient survived or died. All patients underwent surgical debridement. Wound debridement was regularly performed in the post operative period. Of 70 patients, 8 died (11.4%) and 62 survived (88.5%). Difference in age between survivors (median age, 50.0 yr) and non survivors (median age, 54.5 yr) was not significant (p=0.321). Median extent of body surface area involved in necrotizing process in patients who survived and did not survive was 2.4% and 4.9%, respectively (p=0.001). Except for albumin, no significant differences were found between survivors and nonsurvivors. Median admission FGSI scores for survivors and non survivors were 2.1±2.0 and 4.2±3.8, (p=0.331). FGSI score did not predict disease severity and the patient's survival. Metabolic aberrations, extent of disease seemed to be important risk factors for predicting FG severity and patient survival. Copyright © 2010 AEU. Published by Elsevier Espana. All rights reserved.

Human Parotid Gland Alpha-Amylase Secretion as a Function of Chronic Hyperbaric Exposure

DTIC Science & Technology

1979-01-01

parotid ...Pullman, WA 99163 Gilman, S. C, G. J. Fischer, R. J. Biersner, R. D. Thornton, and D. A. Miller. 1979. Human parotid gland alpha-amylase secretion...as a function of chronic hyperbaric exposure. Undersea Biomed. Res. 6(3):303-307.—Secretion of a-amylase by the human parotid gland increased

The role of oxygen-associated therapies for the healing of chronic wounds, particularly in patients with diabetes.

PubMed

Brimson, C H; Nigam, Y

2013-04-01

This paper discusses the role of molecular oxygen as an aid to wound healing, and the potential value of the three major therapies which allow the delivery of oxygen to the wound site: Hyperbaric Oxygen Therapy (HBOT), Topical Oxygen Therapy (TOT) and a new sterile wound dressing, Oxyzyme™. We summarize studies which have been undertaken using these interventions, and discuss their reported effect on chronic, non-healing wounds, in particular, on ulcers associated with Diabetes. The main conclusions drawn from the studies reviewed indicate that therapeutic oxygen can be used as an aid to the healing of chronic wounds; and benefits are clearly evident with the use of both HBOT and TOT. There is also potential for the use of a new, portable, topical oxygen delivery system, oxyzyme. However its use is still embryonic and studies on its effectiveness are limited. More robust measures of its efficacy are urgently needed. © 2012 The Authors. Journal of the European Academy of Dermatology and Venereology © 2012 European Academy of Dermatology and Venereology.

Direct tissue oxygen monitoring by in vivo photoacoustic lifetime imaging (PALI)

NASA Astrophysics Data System (ADS)

Shao, Qi; Morgounova, Ekaterina; Ashkenazi, Shai

2014-03-01

Tissue oxygen plays a critical role in maintaining tissue viability and in various diseases, including response to therapy. Images of oxygen distribution provide the history of tissue hypoxia and evidence of oxygen availability in the circulatory system. Currently available methods of direct measuring or imaging tissue oxygen all have significant limitations. Previously, we have reported a non-invasive in vivo imaging modality based on photoacoustic lifetime. The technique maps the excited triplet state of oxygen-sensitive dye, thus reflects the spatial and temporal distribution of tissue oxygen. We have applied PALI on tumor hypoxia in small animals, and the hypoxic region imaged by PALI is consistent with the site of the tumor imaged by ultrasound. Here, we present two studies of applying PALI to monitor changes of tissue oxygen by modulations. The first study involves an acute ischemia model using a thin thread tied around the hind limb of a normal mouse to reduce the blood flow. PALI images were acquired before, during, and after the restriction. The drop of muscle pO2 and recovery from hypoxia due to reperfusion were observed by PALI tracking the same region. The second study modulates tissue oxygen by controlling the percentage of oxygen the mouse inhales. We demonstrate that PALI is able to reflect the change of oxygen level with respect to both hyperbaric and hypobaric conditions. We expect this technique to be very attractive for a range of clinical applications in which tissue oxygen mapping would improve therapy decision making and treatment planning.

[Cerebellar Infarction After Carbon Monoxide Poisoning and Hyperbaric Oxygen Therapy].

PubMed

Wick, Matthias; Schneiker, André; Bele, Sylvia; Pawlik, Michael; Meyringer, Helmut; Graf, Bernhard; Wendl, Christina; Kieninger, Martin

2017-06-01

We report on a patient who developed a space-occupying cerebellar infarction with occlusive hydrocephalus after a poisoning with carbon monoxide with the intention to commit suicide. A neurosurgical and intensive care therapy were needed. The patient's survival without severe neurological deficits could be secured due to the early detection of the intracerebral lesions. Georg Thieme Verlag KG Stuttgart · New York.

Oxygen Uptake Efficiency Plateau Best Predicts Early Death in Heart Failure

PubMed Central

Hansen, James E.; Stringer, William W.

2012-01-01

Background: The responses of oxygen uptake efficiency (ie, oxygen uptake/ventilation = V˙o2/V˙e) and its highest plateau (OUEP) during incremental cardiopulmonary exercise testing (CPET) in patients with chronic left heart failure (HF) have not been previously reported. We planned to test the hypothesis that OUEP during CPET is the best single predictor of early death in HF. Methods: We evaluated OUEP, slope of V˙o2 to log(V˙e) (oxygen uptake efficiency slope), oscillatory breathing, and all usual resting and CPET measurements in 508 patients with low-ejection-fraction (< 35%) HF. Each had further evaluations at other sites, including cardiac catheterization. Outcomes were 6-month all-reason mortality and morbidity (death or > 24 h cardiac hospitalization). Statistical analyses included area under curve of receiver operating characteristics, ORs, univariate and multivariate Cox regression, and Kaplan-Meier plots. Results: OUEP, which requires only moderate exercise, was often reduced in patients with HF. A low % predicted OUEP was the single best predictor of mortality (P < .0001), with an OR of 13.0 (P < .001). When combined with oscillatory breathing, the OR increased to 56.3, superior to all other resting or exercise parameters or combinations of parameters. Other statistical analyses and morbidity analysis confirmed those findings. Conclusions: OUEP is often reduced in patients with HF. Low % predicted OUEP (< 65% predicted) is the single best predictor of early death, better than any other CPET or other cardiovascular measurement. Paired with oscillatory breathing, it is even more powerful. PMID:22030802

Successful Treatment of Severe Carbon Monoxide Poisoning and Refractory Shock Using Extracorporeal Membrane Oxygenation.

PubMed

Teerapuncharoen, Krittika; Sharma, Nirmal S; Barker, Andrew B; Wille, Keith M; Diaz-Guzman, Enrique

2015-09-01

Carbon monoxide (CO) is the most common cause of poisoning and poisoning-related death in the United States. It is a tasteless and odorless poisonous gas produced from incomplete combustion of hydrocarbons, such as those produced by cars and heating systems. CO rapidly binds to hemoglobin to form carboxyhemoglobin, leading to tissue hypoxia, multiple-organ failure, and cardiovascular collapse. CO also binds to myocardial myoglobin, preventing oxidative phosphorylation in cardiac mitochondria and resulting in cardiac ischemia or stunning and cardiogenic pulmonary edema. Treatment of CO poisoning is mainly supportive, and supplemental oxygen remains the cornerstone of therapy, whereas hyperbaric oxygen therapy is considered for patients with evidence of neurological and myocardial injury. Extracorporeal membrane oxygenation (ECMO) has been utilized effectively in patients with respiratory failure and hemodynamic instability, but its use has rarely been reported in patients with CO poisoning. We report the successful use of venoarterial ECMO in a patient with severe CO poisoning and multiple-organ failure. Copyright © 2015 by Daedalus Enterprises.

Advanced instrumentation for research in diving and hyperbaric medicine.

PubMed

Sieber, Arne; L'Abbate, Antonio; Kuch, Benjamin; Wagner, Matthias; Benassi, Antonio; Passera, Mirko; Bedini, Remo

2010-01-01

Improving the safety of diving and increasing knowledge about the adaptation of the human body to underwater and hyperbaric environment require specifically developed underwater instrumentation for physiological measurements. In fact, none of the routine clinical devices for health control is suitable for in-water and/or under-pressure operation. The present paper addresses novel technological acquisitions and the development of three dedicated devices: * an underwater data logger for recording O2 saturation (reflective pulsoxymetry), two-channel ECG, depth and temperature; * an underwater blood pressure meter based on the oscillometric method; and * an underwater echography system. Moreover, examples of recordings are presented and discussed.

Early adaptation to oxygen is key to the industrially important traits of Lactococcus lactis ssp. cremoris during milk fermentation.

PubMed

Cretenet, Marina; Le Gall, Gwenaëlle; Wegmann, Udo; Even, Sergine; Shearman, Claire; Stentz, Régis; Jeanson, Sophie

2014-12-03

Lactococcus lactis is the most used species in the dairy industry. Its ability to adapt to technological stresses, such as oxidative stress encountered during stirring in the first stages of the cheese-making process, is a key factor to measure its technological performance. This study aimed to understand the response to oxidative stress of Lactococcus lactis subsp. cremoris MG1363 at the transcriptional and metabolic levels in relation to acidification kinetics and growth conditions, especially at an early stage of growth. For those purposes, conditions of hyper-oxygenation were initially fixed for the fermentation. Kinetics of growth and acidification were not affected by the presence of oxygen, indicating a high resistance to oxygen of the L. lactis MG1363 strain. Its resistance was explained by an efficient consumption of oxygen within the first 4 hours of culture, leading to a drop of the redox potential. The efficient consumption of oxygen by the L. lactis MG1363 strain was supported by a coherent and early adaptation to oxygen after 1 hour of culture at both gene expression and metabolic levels. In oxygen metabolism, the over-expression of all the genes of the nrd (ribonucleotide reductases) operon or fhu (ferrichrome ABC transports) genes was particularly significant. In carbon metabolism, the presence of oxygen led to an early shift at the gene level in the pyruvate pathway towards the acetate/2,3-butanediol pathway confirmed by the kinetics of metabolite production. Finally, the MG1363 strain was no longer able to consume oxygen in the stationary growth phase, leading to a drastic loss of culturability as a consequence of cumulative stresses and the absence of gene adaptation at this stage. Combining metabolic and transcriptomic profiling, together with oxygen consumption kinetics, yielded new insights into the whole genome adaptation of L. lactis to initial oxidative stress. An early and transitional adaptation to oxidative stress was revealed for L

Hyperbaric Oxygen Therapy Registry

ClinicalTrials.gov

2018-04-30

Air or Gas Embolism; Carbon Monoxide Poisoning; Clostridial Myositis and Myonecrosis (Gas Gangrene); Crush Injury, Compartment Syndrome & Other Acute Traumatic Ischemias; Decompression Sickness; Peripheral Arterial Insufficiency and Central Retinal Artery Occlusion; Severe Anemia; Intracranial Abscess; Necrotizing Soft Tissue Infections; Osteomyelitis (Refractory); Delayed Radiation Injury (Soft Tissue and Bony Necrosis); Compromised Grafts and Flaps; Acute Thermal Burn Injury; Idiopathic Sudden Sensorineural Hearing Loss

Hyperspectral imaging for early detection of oxygenation and perfusion changes in irradiated skin

NASA Astrophysics Data System (ADS)

Chin, Michael S.; Freniere, Brian B.; Lo, Yuan-Chyuan; Saleeby, Jonathan H.; Baker, Stephen P.; Strom, Heather M.; Ignotz, Ronald A.; Lalikos, Janice F.; Fitzgerald, Thomas J.

2012-02-01

Studies examining acute oxygenation and perfusion changes in irradiated skin are limited. Hyperspectral imaging (HSI), a method of wide-field, diffuse reflectance spectroscopy, provides noninvasive, quantified measurements of cutaneous oxygenation and perfusion. This study examines whether HSI can assess acute changes in oxygenation and perfusion following irradiation. Skin on both flanks of nude mice (n=20) was exposed to 50 Gy of beta radiation from a strontium-90 source. Hyperspectral images were obtained before irradiation and on selected days for three weeks. Skin reaction assessment was performed concurrently with HSI. Desquamative injury formed in all irradiated areas. Skin reactions were first seen on day 7, with peak formation on day 14, and resolution beginning by day 21. HSI demonstrated increased tissue oxygenation on day 1 before cutaneous changes were observed (p<0.001). Further increases over baseline were seen on day 14, but returned to baseline levels by day 21. For perfusion, similar increases were seen on days 1 and 14. Unlike tissue oxygenation, perfusion was decreased below baseline on day 21 (p<0.002). HSI allows for complete visualization and quantification of tissue oxygenation and perfusion changes in irradiated skin, and may also allow prediction of acute skin reactions based on early changes seen after irradiation.

Is there a difference between active opening of the Eustachian tube in a hypobaric surrounding compared to a hyperbaric surrounding?

PubMed

Mikolajczak, Stefanie; Meyer, Moritz Friedo; Felsch, Moritz; Jumah, Masen Dirk; Hüttenbrink, Karl-Bernd; Grosheva, Maria; Luers, Jan-Christoffer; Beutner, Dirk

2015-01-01

The Eustachian tube (ET) is the key to pressure equalization between the middle ear and ambient pressure. To date, little is known about differences of the opening mechanisms under hyper- or hypobaric conditions. Aim of this study was to compare standard ET opening parameters during standardized hypo- and hyperbaric exposures. Thirty healthy participants were exposed to a standardized profile of decompression and compression (SPDC) in a hypo-/hyperbaric pressure chamber. Impedance, expressed as tympanic membrane compliance, was recorded at intervals during the excursions from 1 atmosphere absolute (atm abs) to 0.8 and 1.2 atm abs respectively. Parameters for tubal opening were obtained during SPDC: ET opening pressure (ETOP), ET opening duration (ETOD) and ET opening frequency (ETOF), hypobaric (Phase 1) and hyperbaric (Phase 2) data were compared. Mean value for Valsalva maneuver ETOP was 40.10 ± 19.02 mbar in Phase 2 vs. 42.82 ± 21.75 mbar in Phase 1. For ETOD it was 2.80 ± 2.09 seconds in Phase 2 vs. 2.51 ± 1.90 seconds in Phase 1. For swallowing, mean value for ETOP was 33.47 ± 14.50 mbar in Phase 2 vs. 28.44 ± 14.04 in Phase 1. ETOD was 0.82 ± 0.60 seconds in Phase 2 vs. 0.76 ± 0.55 seconds in Phase 1. There was no statistical significance for ETOP, ETOD and ETOF between the two phases. No statistical significant difference was evident for active pressure equalization (Valsalva and swallowing) between a hyperbaric setting (dive) and a hypobaric setting (flight) in healthy subjects.

Effect of process parameters on metal transfer of hyperbaric GMAW of duplex stainless steels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olsen, J.M.; Dos Santos, J.F.; Richardson, I.M.

1994-12-31

This work presents the preliminary results of a comprehensive and systematic evaluation of current rise and fall rates as well as shielding gas composition and their affect on the metal transfer, when duplex stainless steels are GMA welded under hyperbaric conditions using the short circuit metal transfer mode. The evaluation of the test results are based on an examination of the welding process signals recorded on a transient recorder. Over a time period of 500 ms, the signal was measured to assess the process instability, current rise and fall rates and their inter-relationship. The results presented in this study indicatemore » that for a given welding condition, the appropriate selection of current rise and fall rates can minimize the effect of instabilities caused by high ambient pressure. The presence of active gases in the shielding did not significantly affect the metal transfer behavior. All the experiments described in this work have been carried out in the hyperbaric test facilities of the GKSS-Forschungszentrum in Germany.« less

[Diagnosis and treatment of diving accidents. New German guidelines for diving accidents 2014-2017].

PubMed

Jüttner, B; Wölfel, C; Liedtke, H; Meyne, K; Werr, H; Bräuer, T; Kemmerer, M; Schmeißer, G; Piepho, T; Müller, O; Schöppenthau, H

2015-06-01

In 2015 the German Society for Diving and Hyperbaric Medicine (GTÜM) and the Swiss Underwater and Hyperbaric Medical Society (SUHMS) published the updated guidelines on diving accidents 2014-2017. These multidisciplinary guidelines were developed within a structured consensus process by members of the German Interdisciplinary Association for Intensive Care and Emergency Medicine (DIVI), the Sports Divers Association (VDST), the Naval Medical Institute (SchiffMedInst), the Social Accident Insurance Institution for the Building Trade (BG BAU), the Association of Hyperbaric Treatment Centers (VDD) and the Society of Occupational and Environmental Medicine (DGAUM). This consensus-based guidelines project (development grade S2k) with a representative group of developers was conducted by the Association of Scientific Medical Societies in Germany. It provides information and instructions according to up to date evidence to all divers and other lay persons for first aid recommendations to physician first responders and emergency physicians as well as paramedics and all physicians at therapeutic hyperbaric chambers for the diagnostics and treatment of diving accidents. To assist in implementing the guideline recommendations, this article summarizes the rationale, purpose and the following key action statements: on-site 100% oxygen first aid treatment, still patient positioning and fluid administration are recommended. Hyperbaric oxygen (HBO) recompression remains unchanged the established treatment in severe cases with no therapeutic alternatives. The basic treatment scheme recommended for diving accidents is hyperbaric oxygenation at 280 kPa. For quality management purposes there is a need in the future for a nationwide register of hyperbaric therapy.

Report of Evaluation of Decompression Sickness, Beale AFB, 10-14 Aug 2009

DTIC Science & Technology

2009-09-01

MICHAELSON, Col, USAF, MC, SFS Chief, Hyperbaric Medicine Branch //SIGNED// JAMES W. WEISSMANN, Col, USAF, BSC Chief, Aerospace Medicine...Robert S Michaelson (Chief of Hyperbaric Medicine at USAFSAM), Dr. Andy Pilmanis (Consultant), and Dr. Tom Morgan (711 HPW/HPS). BACKGROUND The...without consent of originator’s office. MP = Mission Pilot HBOT = Hyperbaric Oxygen Treatment CNS = Central Nervous System HA = headache BAFB = Beale

Combined use of hyperbaric and hypobaric ropivacaine significantly improves hemodynamic characteristics in spinal anesthesia for caesarean section: a prospective, double-blind, randomized, controlled study.

PubMed

Quan, ZheFeng; Tian, Ming; Chi, Ping; Li, Xin; He, HaiLi; Luo, Chao

2015-01-01

To observe the hemodynamic changes of parturients in the combined use of hyperbaric (4 mg) and hypobaric (6 mg) ropivacaine during spinal anesthesia for caesarean section in this randomized double-blind study. Parturients (n = 136) undergoing elective cesarean delivery were randomly and equally allocated to receive either combined hyperbaric and hypobaric ropivacaine (Group A) or hyperbaric ropivacaine (Group B). Outcome measures were: hemodynamic characteristics, maximum height of sensory block, time to achieve T8 sensory blockade level, incidence of complications, Apgar scores at 1 and 5 min, and neonatal blood gas analysis. Group A had a lower level of sensory blockade (T6 [T6-T7]) and longer time to achieve T8 sensory blockade level (8 ± 1.3 min) than did patients in Group B (T3 [T2-T4] and 5 ± 1.0 min, respectively; P < 0.001, both). The incidence rates for hypotension, nausea, and vomiting were significantly lower in Group A (13%, 10%, and 3%, respectively) than Group B (66%, 31%, and 13%; P < 0.001, P = 0.003, P = 0.028). Combined use of hyperbaric (4 mg) and hypobaric (6 mg) ropivacaine significantly decreased the incidences of hypotension and complications in spinal anesthesia for caesarean section by extending induction time and decreasing the level of sensory blockade. Chinese Clinical Trial Register ChiCTR-TRC-13004622.

The rise of oxygen in Earth's early ocean and atmosphere.

PubMed

Lyons, Timothy W; Reinhard, Christopher T; Planavsky, Noah J

2014-02-20

The rapid increase of carbon dioxide concentration in Earth's modern atmosphere is a matter of major concern. But for the atmosphere of roughly two-and-half billion years ago, interest centres on a different gas: free oxygen (O2) spawned by early biological production. The initial increase of O2 in the atmosphere, its delayed build-up in the ocean, its increase to near-modern levels in the sea and air two billion years later, and its cause-and-effect relationship with life are among the most compelling stories in Earth's history.

Photoluminescence due to early stage of oxygen precipitation in multicrystalline Si for solar cells

NASA Astrophysics Data System (ADS)

Higuchi, Fumito; Tajima, Michio; Ogura, Atsushi

2017-07-01

To analyze the early stage of oxygen precipitation in n-type multicrytalline Si, the spectral change of photoluminescence (PL) induced by thermal treatment at 450-650 °C was investigated in relation to the changes in excess donor and interstitial oxygen concentrations. We observed the characteristic PL bands in the near-band-edge region and sharp lines in the deep-level region in correspondence with the generation of thermal donors and new donors. The observed PL spectral variation is essentially the same as that in Czochralski-grown Si annealed at 450-650 °C.

Preflight studies on tolerance of pocket mice to oxygen and heat. IV - Observations on the brain

NASA Technical Reports Server (NTRS)

Bailey, O. T.; Ordy, J. M.; Haymaker, W.

1975-01-01

Experiments designed to ascertain the effects of oxygen at 8, 10, and 12 psi partial pressure on the brains of pocket mice (Perognathus longimembris) were carried out at room temperature (24 C, 75 F) and at 32 C (90 F). The animals exposed to 8-12 psi at 32 C had been in earlier KO2 oxygen tests. Five animals exposed either to 10 or 12 psi (517 mm or 620 mm Hg) O2 partial pressure at 32 C died during the course of the tests, possibly as a consequence of injury sustained by the earlier O2 partial pressure testing. Autopsy was not carried out. In the other 36 exposed animals, no pathological changes were observed in the brain. It is thus highly probable that oxygen pressures at the hyperbaric levels to which the pocket mice would be exposed during the Apollo XVII mission would not result in any lesions in the brain.

A comparison of thoracic spinal anesthesia with low-dose isobaric and low-dose hyperbaric bupivacaine for orthopedic surgery: A randomized controlled trial

PubMed Central

Imbelloni, Luiz Eduardo; Gouveia, Marildo A.

2014-01-01

Background: The thoracic spinal anesthesia was first described in 1909 and recently revised for various surgical procedures. This is a prospective study aims to evaluate the parameters of the thoracic spinal anesthesia (latency, motor block and paresthesia), the incidence of cardiovascular changes and complications comparing low doses of isobaric and hyperbaric bupivacaine. Materials and Methods: A total of 200 orthopedic patients operated under spinal anesthesia were included in this study. Spinal anesthesia was between T9-T10, with a 27G cutting point or pencil tip in lateral or sitting. Spinal anesthesia was performed with 0.5% bupivacaine isobaric or hyperbaric. Patients remained in cephalad or head down position 10-20° for 10 minutes. We evaluated the demographics, analgesia, and degree of motor block, incidence of paresthesia, bradycardia, hypotension, anesthesia success and neurological complications. Results: All patients developed spinal and there was no failure. The solution did not affect the onset of the blockade. The duration of motor block was greater than the sensitive with isobaric. The duration of sensory block was greater than the motor block with hyperbaric solution. The incidence of paresthesia was 4%, with no difference between the needles. The incidence of hypotension was 12.5% with no difference between the solutions. There was no neurological damage in all patients. Conclusion: The beginning of the block is fast regardless of the solution used. By providing a sensory block of longer duration than the motor block hyperbaric bupivacaine is reflected in a better indication. Thoracic spinal anesthesia provides excellent anesthesia for lower limb orthopedic surgery PMID:25886099

Management of radiotherapy-induced salivary hypofunction and consequent xerostomia in patients with oral or head and neck cancer: meta-analysis and literature review.

PubMed

Lovelace, Tiffany L; Fox, Nyssa F; Sood, Amit J; Nguyen, Shaun A; Day, Terry A

2014-05-01

To analyze the efficacy of various treatment options for radiation-induced hyposalivation in patients with head and neck cancer. A literature review and meta-analysis was performed on all appropriate literature identified via MEDLINE/PubMed. Fourteen articles were identified that met inclusion criteria for review, and 8 articles qualified for inclusion in the meta-analysis. The available literature addressed both objective and subjective responses of hyposalivation, xerostomia, or both to cholinergic agonists (such as pilocarpine and cevimeline), salivary substitutes, hyperbaric oxygen, and acupuncture. This analysis indicated that cholinergic agonists were more effective in treating radiation-induced hyposalivation compared with salivary substitutes, hyperbaric oxygen, and acupuncture. However, other treatment modalities, such as salivary substitutes and hyperbaric oxygen, were also found to subjectively improve patients' perception of xerostomia. Copyright © 2014 Elsevier Inc. All rights reserved.

The effect of spinal hyperbaric bupivacaine-fentanyl or hyperbaric bupivacaine on uterine tone and fetal heart rate in labouring women: a randomised controlled study.

PubMed

Kuberan, A; Jain, K; Bagga, R; Makkar, J K

2018-07-01

The mechanism for fetal heart rate abnormalities following spinal opioids remains controversial. We evaluated uterine tone, using an intra-uterine pressure catheter, and fetal heart rate abnormalities in 30 women in spontaneous labour with cervical dilation of 3-5 cm having combined spinal-epidural analgesia. Women were randomly assigned to receive a spinal with 2.0 mg hyperbaric bupivacaine plus 15 μg fentanyl, or 2.5 mg hyperbaric bupivacaine. The primary outcome measure was an increase > 10 mmHg in baseline uterine tone in the 30-min period following spinal injection. Only three (20%) women who had a bupivacaine-fentanyl spinal showed a > 10 mmHg increase in baseline tone vs. none who had bupivacaine (p = 0.63). The mean (SD) baseline uterine tone after the spinal injection was 13.3 (7.0) mmHg in the bupivacaine-fentanyl group and 7.7 (2.5) mmHg in the bupivacaine group (p = 0.01). Seven (47%) in the bupivacaine-fentanyl group showed new onset fetal heart rate changes during the 30-min period after the spinal, compared with two (13%) in the bupivacaine group (p = 0.04); however, these were transient and responded to intra-uterine resuscitation. Pain scores, sensory and motor block as well as neonatal outcomes were comparable between the groups. We found that raised baseline uterine tone was not more frequent when using bupivacaine-fentanyl rather than bupivacaine in the spinal component of combined spinal-epidural, although absolute values of baseline tone were higher, and fetal heart rate changes more frequent, in the former group. © 2018 The Association of Anaesthetists of Great Britain and Ireland.

Performance of raw bovine meat preservation by hyperbaric storage (quasi energetically costless) compared to refrigeration.

PubMed

Freitas, Paulo; Pereira, Sofia A; Santos, Mauro D; Alves, Susana P; Bessa, Rui J B; Delgadillo, Ivonne; Saraiva, Jorge A

2016-11-01

Hyperbaric storage at room temperature (without temperature control) of raw bovine meat was studied and compared to refrigeration. Samples were first stored for 12h at 50, 100 and 150MPa, and in a second set of experiments, for a longer period of 10days at 50MPa. For the 12h storage, refrigeration and 50MPa had a similar microbial growth inhibition effect and, at 100 and 150MPa an additional microbial inactivation effect was found. For the longer experiment (10days at 50MPa) results pointed for a shelf-life increase of raw beef compared to samples stored under refrigeration. For both tests (12h and 10days) samples preserved under pressure showed no detrimental effect on physicochemical parameters comparatively to the initial and refrigerated samples. These results indicate that hyperbaric storage at room temperature not only allows high energy savings, but additionally has potential to extend the shelf-life of a perishable food product compared to refrigeration. Copyright © 2016 Elsevier Ltd. All rights reserved.

Combined Use of Hyperbaric and Hypobaric Ropivacaine Significantly Improves Hemodynamic Characteristics in Spinal Anesthesia for Caesarean Section: A Prospective, Double-Blind, Randomized, Controlled Study

PubMed Central

Quan, ZheFeng; Tian, Ming; Chi, Ping; Li, Xin; He, HaiLi; Luo, Chao

2015-01-01

Purpose To observe the hemodynamic changes of parturients in the combined use of hyperbaric (4 mg) and hypobaric (6 mg) ropivacaine during spinal anesthesia for caesarean section in this randomized double-blind study. Methods Parturients (n = 136) undergoing elective cesarean delivery were randomly and equally allocated to receive either combined hyperbaric and hypobaric ropivacaine (Group A) or hyperbaric ropivacaine (Group B). Outcome measures were: hemodynamic characteristics, maximum height of sensory block, time to achieve T8 sensory blockade level, incidence of complications, Apgar scores at 1 and 5 min, and neonatal blood gas analysis. Results Group A had a lower level of sensory blockade (T6 [T6-T7]) and longer time to achieve T8 sensory blockade level (8 ± 1.3 min) than did patients in Group B (T3 [T2-T4] and 5 ± 1.0 min, respectively; P < 0.001, both). The incidence rates for hypotension, nausea, and vomiting were significantly lower in Group A (13%, 10%, and 3%, respectively) than Group B (66%, 31%, and 13%; P < 0.001, P = 0.003, P = 0.028). Conclusions Combined use of hyperbaric (4 mg) and hypobaric (6 mg) ropivacaine significantly decreased the incidences of hypotension and complications in spinal anesthesia for caesarean section by extending induction time and decreasing the level of sensory blockade. Trial Registration Chinese Clinical Trial Register ChiCTR-TRC-13004622 PMID:25970485

[Functional state of various physiological systems of the human body during respiration of neon-oxygen mixture at depth up to 400 meters].

PubMed

Poleshuk, I P; Genin, A M; Unku, R D; Mikhnenko, A E; Sementsov, V N; Suvorov, A V

1991-01-01

Hyperbaric neon-oxygen mixture has been studied for the effect of its high density under pressure of 41 ata on basic physiological functions of human organism. Typical changes of the cardiorespiratory system and tissue respiration parameters are revealed. Changes in physical working capacity are shown. Exposure to gaseous medium of high pressure and density is accompanied by the development of some compensatory-adaptive reactions. The possibility to perform mid-hard physical work is attained with overstrain of respiration and circulation function.

The effectiveness of ground level post-flight 100 percent oxygen breathing as therapy for pain-only altitude Decompression Sickness (DCS)

NASA Technical Reports Server (NTRS)

Demboski, John T.; Pilmanis, Andrew A.

1994-01-01

In both the aviation and space environments, decompression sickness (DCS) is an operational limitation. Hyperbaric recompression is the most efficacious treatment for altitude DCS. However, the inherent recompression of descent to ground level while breathing oxygen is in itself therapy for altitude DCS. If pain-only DCS occurs during a hypobaric exposure, and the symptoms resolver during descent, ground level post-flight breathing of 100% O2 for 2 hours (GLO2) is considered sufficient treatment by USAF Regulation 161-21. The effectiveness of the GLO2 treatment protocol is defined.

The Roles of Primary Cilia in Cardiovascular System

DTIC Science & Technology

2016-10-01

mitochondrial generation of hydrogen peroxide. General properties and effect of hyperbaric oxygen . Biochem J 134:707–716. Boveris A, Oshino N, Chance B. 1972...The mitochondrial generation of hydrogen peroxide. General properties and effect of hyperbaric oxygen . Biochem J 134:707–716. Boveris A, Oshino N...Aim 1.2 (months 13-30): We will examine signaling mechanisms of cilia & their effects on blood pressure. Aim 2 (months 7-36). We will study

Increased oxygen exposure alters collagen expression and tissue architecture during ligature-induced periodontitis.

PubMed

Gajendrareddy, P K; Junges, R; Cygan, G; Zhao, Y; Marucha, P T; Engeland, C G

2017-06-01

The aim of this study was to evaluate the effects of increased oxygen availability on gene expression and on collagen deposition/maturation in the periodontium following disease. Male Wistar rats had ligatures placed around their molars to induce periodontal disease, and a subset of animals underwent hyperbaric oxygen (HBO) treatment for 2 h twice per day. At 15 and 28 d, tissue gene expression of COL1A1, transforming growth factor-β1 and alkaline phosphatase was determined; other histological samples were stained with Picrosirius red to evaluate levels of collagen deposition, maturation and thickness. In animals that underwent HBO treatment, type I collagen expression was higher and collagen deposition, maturation and thickness were more robust. Reduced mRNA levels of transforming growth factor-beta1 and alkaline phosphatase in HBO-treated rats on day 28 suggested that a quicker resolution in both soft tissue and bone remodeling occurred following oxygen treatment. No differences in inflammation were observed between groups. The extracellular matrix regenerated more quickly in the HBO-treated group as evidenced by higher collagen expression, deposition and maturation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Magma Ocean Depth and Oxygen Fugacity in the Early Earth--Implications for Biochemistry.

PubMed

Righter, Kevin

2015-09-01

A large class of elements, referred to as the siderophile (iron-loving) elements, in the Earth's mantle can be explained by an early deep magma ocean on the early Earth in which the mantle equilibrated with metallic liquid (core liquid). This stage would have affected the distribution of some of the classic volatile elements that are also essential ingredients for life and biochemistry - H, C, S, and N. Estimates are made of the H, C, S, and N contents of Earth's early mantle after core formation, considering the effects of variable temperature, pressure, oxygen fugacity, and composition on their partitioning. Assessment is made of whether additional, exogenous, sources are required to explain the observed mantle concentrations, and areas are identified where additional data and experimentation would lead to an improved understanding of this phase of Earth's history.

An overview of changes in pressure values of the middle ear using impedance audiometry among diver candidates in a hyperbaric chamber before and after a pressure test

NASA Astrophysics Data System (ADS)

Anoraga, J. S.; Bramantyo, B.; Bardosono, S.; Simanungkalit, S. H.; Basiruddin, J.

2017-08-01

Impedance audiometry is not yet routinely used in pressure tests, especially in Indonesia. Direct exposure to pressure in a hyperbaric chamber is sometimes without any assessment of the middle ear or the Eustachian tube function (ETF) of ventilation. Impedance audiometry examinations are important to assess ETF ventilation. This study determined the middle ear pressure value changes associated with the ETF (ventilation) of prospective divers. This study included 29 prospective divers aged 20-40 years without conductive hearing loss. All subjects underwent a modified diving impedance audiometry examination both before and after the pressure test in a double-lock hyperbaric chamber. Using the Toynbee maneuver, the values obtained for changes of pressure in the middle ear were significant before and after the pressure test in the right and left ears: p < 0.001 and p = 0.018, respectively. The impedance audiometry examination is necessary for the selection of candidate divers undergoing pressure tests within a hyperbaric chamber.

Hydrogen gas alleviates oxygen toxicity by reducing hydroxyl radical levels in PC12 cells

PubMed Central

Yu, Junchao; Yu, Qiuhong; Liu, Yaling; Zhang, Ruiyun; Xue, Lianbi

2017-01-01

Hyperbaric oxygen (HBO) therapy through breathing oxygen at the pressure of above 1 atmosphere absolute (ATA) is useful for varieties of clinical conditions, especially hypoxic-ischemic diseases. Because of generation of reactive oxygen species (ROS), breathing oxygen gas at high pressures can cause oxygen toxicity in the central nervous system, leading to multiple neurological dysfunction, which limits the use of HBO therapy. Studies have shown that Hydrogen gas (H2) can diminish oxidative stress and effectively reduce active ROS associated with diseases. However, the effect of H2 on ROS generated from HBO therapy remains unclear. In this study, we investigated the effect of H2 on ROS during HBO therapy using PC12 cells. PC12 cells cultured in medium were exposed to oxygen gas or mixed oxygen gas and H2 at 1 ATA or 5 ATA. Cells viability and oxidation products and ROS were determined. The data showed that H2 promoted the cell viability and inhibited the damage in the cell and mitochondria membrane, reduced the levels of lipid peroxidation and DNA oxidation, and selectively decreased the levels of •OH but not disturbing the levels of O2•-, H2O2, or NO• in PC12 cells during HBO therapy. These results indicated that H2 effectively reduced •OH, protected cells against oxygen toxicity resulting from HBO therapy, and had no effect on other ROS. Our data supported that H2 could be potentially used as an antioxidant during HBO therapy. PMID:28362819

Hydrogen gas alleviates oxygen toxicity by reducing hydroxyl radical levels in PC12 cells.

PubMed

Yu, Junchao; Yu, Qiuhong; Liu, Yaling; Zhang, Ruiyun; Xue, Lianbi

2017-01-01

Hyperbaric oxygen (HBO) therapy through breathing oxygen at the pressure of above 1 atmosphere absolute (ATA) is useful for varieties of clinical conditions, especially hypoxic-ischemic diseases. Because of generation of reactive oxygen species (ROS), breathing oxygen gas at high pressures can cause oxygen toxicity in the central nervous system, leading to multiple neurological dysfunction, which limits the use of HBO therapy. Studies have shown that Hydrogen gas (H2) can diminish oxidative stress and effectively reduce active ROS associated with diseases. However, the effect of H2 on ROS generated from HBO therapy remains unclear. In this study, we investigated the effect of H2 on ROS during HBO therapy using PC12 cells. PC12 cells cultured in medium were exposed to oxygen gas or mixed oxygen gas and H2 at 1 ATA or 5 ATA. Cells viability and oxidation products and ROS were determined. The data showed that H2 promoted the cell viability and inhibited the damage in the cell and mitochondria membrane, reduced the levels of lipid peroxidation and DNA oxidation, and selectively decreased the levels of •OH but not disturbing the levels of O2•-, H2O2, or NO• in PC12 cells during HBO therapy. These results indicated that H2 effectively reduced •OH, protected cells against oxygen toxicity resulting from HBO therapy, and had no effect on other ROS. Our data supported that H2 could be potentially used as an antioxidant during HBO therapy.

Hyperbaric bupivacaine 2.5 mg prolongs analgesia compared with plain bupivacaine when added to intrathecal fentanyl 25 microg in advanced labor.

PubMed

Teoh, Wendy H L; Sia, Alex T H

2003-09-01

We investigated the effect of sequential administration of intrathecal (IT) hyperbaric bupivacaine (after the initial administration of IT hypobaric fentanyl) on the duration of spinal analgesia. Thirty-seven nulliparous parturients with a cervical dilation >/= 5 cm were randomized to receive either IT fentanyl 25 micro g and plain bupivacaine 2.5 mg (group P; n = 19) or IT fentanyl 25 micro g and hyperbaric (with 8% glucose) bupivacaine 2.5 mg (group H; n = 18). The two components of the IT injectate were administered sequentially (fentanyl 25 micro g diluted in 2 mL of normal saline, immediately followed by 0.5 mL of 0.5% bupivacaine). Patients were then positioned with their torso elevated at 30 degrees for 30 min. Pain scores using 0-100 visual analog scales were collected before combined spinal/epidural analgesia and at 5, 15, and 30 min after the block. Patients in Group H had a longer median duration of analgesia (122 min; range, 80-210 min) than Group P (95 min; range, 75-125 min) (P < 0.01). Group H also had a more limited dermatomal spread (median highest sensory level of T8 versus T4 in group P; P < 0.05). The side-effect profile was similar. Under these circumstances, hyperbaric bupivacaine conferred an increased duration of IT analgesia compared with plain bupivacaine.

Cerebral oxygen metabolism in patients with early Parkinson's disease.

PubMed

Borghammer, Per; Cumming, Paul; Østergaard, Karen; Gjedde, Albert; Rodell, Anders; Bailey, Christopher J; Vafaee, Manoucher S

2012-02-15

Decreased activity of the mitochondrial electron transport chain (ETC) has been implicated in the pathogenesis of Parkinson's disease (PD). This model would most likely predict a decrease in the rate of cerebral oxygen consumption (CMRO(2)). To test this hypothesis, we compared CMRO(2) and cerebral blood flow (CBF) PET scans from PD patients and healthy controls. Nine early-stage PD patients and 15 healthy age-matched controls underwent PET scans for quantitative mapping of CMRO(2) and CBF. Between-group differences were evaluated for absolute data and intensity-normalized values. No group differences were detected in regional magnitudes of CMRO(2) or CBF. Upon normalization using the reference cluster method, significant relative CMRO(2) decreases were evident in widespread prefrontal, parieto-occipital, and lateral temporal regions. Sensory-motor and subcortical regions, brainstem, and the cerebellum were spared. A similar pattern was evident in normalized CBF data, as described previously. While the data did not reveal substantially altered absolute CMRO(2) in brain of PD patients, employing data-driven intensity normalization revealed widespread relative CMRO(2) decreases in cerebral cortex. The detected pattern was very similar to that reported in earlier CBF and CMRglc studies of PD, and in the CBF images from the same subjects. Thus, the present results are consistent with the occurrence of parallel declines in CMRO(2), CBF, and CMRglc in spatially contiguous cortical regions in early PD, and support the hypothesis that ETC dysfunction could be a primary pathogenic mechanism in early PD. Copyright © 2011 Elsevier B.V. All rights reserved.

Definition of tolerance to continuous hyperoxia in man - An abstract report of Predictive Studies V

NASA Technical Reports Server (NTRS)

Lambertsen, C. J.; Clark, J. M.; Gelfand, R.; Pisarello, J. B.; Cobbs, W. H.

1987-01-01

The overall goals, design, and procedures of Predictive Studies V are discussed as well as the specific elements of neural effects produced by prolonged hyperoxia. It is noted that Predictive Studies V study of oxygen poisoning in normal men during uninterrupted exposures to oxygen over the range of hyperbaric oxygen exposure most useful in diving, the treatment of gas lesion diseases, and general hyperbaric medicine. It is found that, throughout the study, the most striking observations were related to effects on visual function, on the lung, and the probable interactions of preconvulsive neural activity with effects on cardiovascular and respiratory-pulmonary functions.

[Hypobaric 0.15% bupivacaine versus hyperbaric 0.5% bupivacaine for posterior (dorsal) spinal block in outpatient anorectal surgery.].

PubMed

Imbelloni, Luiz Eduardo; Vieira, Eneida Maria; Gouveia, M A; Netinho, João Gomes; Cordeiro, José Antonio

2006-12-01

The aim of this study was to study low dose hypobaric 0.15% bupivacaine and hyperbaric 0.5% bupivacaine in outpatient anorectal surgical procedures. Two groups of 50 patients, physical status ASA I and II, undergoing anorectal surgical procedures in a jackknife position, received 6 mg of hypobaric 0.15% bupivacaine in the surgical position (Group 1) or 6 mg of hyperbaric 0.5% bupivacaine in the sitting position for 5 minutes, after which they were placed in a jackknife position (Group 2). Sensitive and motor blockade, time of first urination, ambulation, complications, and the need for analgesics were evaluated. Patients were followed until the third postoperative day and questioned whether they experienced post-puncture headache or temporary neurological symptoms, and until the 30th day and questioned about permanent neurological complications. The test t Student, Mood's median, and Fisher Exact test were used for statistical analysis, and a p < 0.05 was considered significant. Every patient in Group 1 presented selective blockade of the posterior sacral nerve roots, while patients in Group 2 experienced blockade of the anterior and posterior nerve roots. Blockade was significantly higher in Group 1. Motor blockade was significantly less severe in Group 1. Forty-nine patients in Group 1 transferred to the stretcher unassisted while only 40 patients in Group 2 were able to do so. Recovery in Group 1 occurred in 105 +/- 25 minutes and in 95 +/- 15 minutes in Group 2, and this difference was not statistically significant. There were no hemodynamic changes, nausea or vomiting, urine retention, or post-puncture headache. Anorectal surgical procedures under spinal block with low dose bupivacaine, hyperbaric or hypobaric, can be safely done.

Change of oxygen pressure in glioblastoma tissue under various conditions.

PubMed

Beppu, Takaaki; Kamada, Katsura; Yoshida, Yuki; Arai, Hiroshi; Ogasawara, Kuniaki; Ogawa, Akira

2002-05-01

Measurement of oxygen pressure (pO2) in tumor tissue is important, because pO2 is a major factor for radiosensitivity in malignant glioma treatment. We attempted to elucidate the changes in pO2 level in glioblastoma tissue of patients under various conditions. Eighteen patients with newly diagnosed glioblastoma were recruited to this study. Disposable Clark-type electrodes were inserted using CT guided stereotactic surgery under local anesthesia and left in the intra- and peritumoral regions. pO2 was measured in patients under conditions of being awake and asleep, inhaling 100% O2, being administered osmotic diuretics and following hyperbaric oxygen exposure (HBO). Peritumoral tissue had a significantly higher pO2 value in both awake and sleeping patients. O2 inhalation could not significantly increase the pO2 level, whereas administration of osmotic diuretics induced an increase in pO2 levels in peritumoral tissue alone. The pO2 levels were significantly increased in both regions after HBO, and a high pO2 level was maintained until 15 min after HBO in both regions. It is possible that the pO2 level in peritumoral tissue is affected by intracranial pressure, whereas that in the intratumoral tissue is usually low. HBO was the optimal procedure for oxygenation, but its benefit was reduced over time.

S-nitrosylation of GAD65 is implicated in decreased GAD activity and oxygen-induced seizures.

PubMed

Gasier, Heath G; Demchenko, Ivan T; Tatro, Lynn G; Piantadosi, Claude A

2017-07-13

Breathing oxygen at partial pressures ≥2.5 atmospheres absolute, which can occur in diving and hyperbaric oxygen (HBO 2 ) therapy, can rapidly become toxic to the central nervous system (CNS). This neurotoxicity culminates in generalized EEG epileptiform discharges, tonic-clonic convulsions and ultimately death. Increased production of neuronal nitric oxide (NO) has been implicated in eliciting hyperoxic seizures by altering the equilibrium between glutamatergic and GABAergic synaptic transmission. Inhibition of glutamic acid decarboxylase (GAD) activity in HBO 2 promotes this imbalance; however, the mechanisms by which this occurs is unknown. Therefore, we conducted a series of experiments using mice, a species that is highly susceptible to CNS oxygen toxicity, to explore the possibility that NO modulates GABA metabolism. Mice were exposed to 100% oxygen at 4 ATA for various durations, and brain GAD and GABA transaminase (GABA-T) activity, as well as S-nitrosylation of GAD65 and GAD67 were determined. HBO 2 inhibited GAD activity by 50% and this was negatively correlated with S-nitrosylation of GAD65, whereas GABA-T activity and S-nitrosylation of GAD67 were unaltered. These results suggest a new mechanism by which NO alters GABA metabolism, leading to neuroexcitation and seizures in HBO 2 . Published by Elsevier B.V.

The Association of Early Blood Oxygenation with Child Development in Preterm Infants with Acute Respiratory Disorders

PubMed Central

Smith, Karen E.; Keeney, Susan; Zhang, Lifang; Perez-Polo, Regino; Rassin, David K.

2008-01-01

The potential negative impact of early blood oxygenation on development of specific cognitive and motor outcomes in children born at very low birth weight (VLBW; 1000 − 1500g) has not been examined even though these infants are exposed to varying durations and amounts of oxygen as part of their neonatal care. While this is the largest group of preterm infants, they receive much less research attention than extremely low birth weight infants (ELBW < 1000g). Although neonatologists are questioning the routine use of oxygen therapy for all neonates, research has focused primarily on the more medically fragile ELBW infants. To date there are no systematic studies available to guide decision making for oxygen supplementation for a large segment of the preterm infant population. The aim of the present study was to determine if there is an association between blood oxygenation in the first four hours of life and specific cognitive and motor skills in preterm infants with acute respiratory disorders but no severe intracranial insult using a selected cohort from a longitudinal study children recruited in 1991 and 1992 designed to examine the role of biological immaturity as defined by gestational age and parenting in development. From this cohort, 55 children had acute respiratory disorders without severe intracranial insult. Of these, 35 children had at least one partial pressure of oxygen obtained from arterial blood (PaO2) during the first four hours of life as part of their clinical care. Higher early PaO2 values were associated with lower impulse control and attention skills in the elementary school age period. Models that examined for relations between PaO2 values that also included birth weight and parenting quality across the first year of life revealed that higher PaO2 remained associated with impulse control but not attention skills. Birth weight was not associated with any outcomes. These results suggest that hyperoxia may be a risk factor for developmental

Effect of cooled hyperbaric bupivacaine on unilateral spinal anesthesia success rate and hemodynamic complications in inguinal hernia surgery.

PubMed

Tomak, Yakup; Erdivanli, Basar; Sen, Ahmet; Bostan, Habib; Budak, Ersel Tan; Pergel, Ahmet

2016-02-01

We hypothesized that cooling hyperbaric bupivacaine from 23 to 5 °C may limit the intrathecal spread of bupivacaine and therefore increase the success rate of unilateral spinal anesthesia and decrease the rate of hemodynamic complications. A hundred patients scheduled for elective unilateral inguinal hernia surgery were randomly allocated to receive 1.8 ml of 0.5 % hyperbaric bupivacaine intrathecally at either 5 °C (group I, n = 50) or at 23 °C (group II, n = 50). Following spinal block at the L2-3 interspace, the lateral decubitus position was maintained for 15 min. Unilateral spinal anesthesia was assessed and confirmed at 15 and 30 min. The levels of sensory and motor block on the operative side were evaluated until complete resolution. The rate of unilateral spinal anesthesia at 15 and 30 min was significantly higher in group I (p = 0.015 and 0.028, respectively). Hypotensive events and bradycardia were significantly rarer in group I (p = 0.014 and 0.037, respectively). The density and viscosity of the solution at 5 °C was significantly higher than at 23 °C (p < 0.0001). Compared with group II, sensory block peaked later in group I (17.4 vs 12.6 min) and at a lower level (T9 vs T7), and two-segment regression of sensory block (76.4 vs 84.3 min) and motor block recovery was shorter (157.6 vs 193.4 min) (p < 0.0001). Cooling of hyperbaric bupivacaine to 5 °C increased the density and viscosity of the solution and the success rate of unilateral spinal anesthesia, and decreased the hemodynamic complication rate.

Affect of Early Life Oxygen Exposure on Proper Lung Development and Response to Respiratory Viral Infections

PubMed Central

Domm, William; Misra, Ravi S.; O’Reilly, Michael A.

2015-01-01

Children born preterm often exhibit reduced lung function and increased severity of response to respiratory viruses, suggesting that premature birth has compromised proper development of the respiratory epithelium and innate immune defenses. Increasing evidence suggests that premature birth promotes aberrant lung development likely due to the neonatal oxygen transition occurring before pulmonary development has matured. Given that preterm infants are born at a point of time where their immune system is also still developing, early life oxygen exposure may also be disrupting proper development of innate immunity. Here, we review current literature in hopes of stimulating research that enhances understanding of how the oxygen environment at birth influences lung development and host defense. This knowledge may help identify those children at risk for disease and ideally culminate in the development of novel therapies that improve their health. PMID:26322310

Hyperbaric Versus Isobaric Bupivacaine for Spinal Anesthesia: Systematic Review and Meta-analysis for Adult Patients Undergoing Noncesarean Delivery Surgery.

PubMed

Uppal, Vishal; Retter, Susanne; Shanthanna, Harsha; Prabhakar, Christopher; McKeen, Dolores M

2017-11-01

It is widely believed that the choice between isobaric bupivacaine and hyperbaric bupivacaine formulations alters the block characteristics for the conduct of surgery under spinal anesthesia. The aim of this study was to systematically review the comparative evidence regarding the effectiveness and safety of the 2 formulations when used for spinal anesthesia for adult noncesarean delivery surgery. Key electronic databases were searched for randomized controlled trials, excluding cesarean delivery surgeries under spinal anesthesia, without any language or date restrictions. The primary outcome measure for this review was the failure of spinal anesthesia. Two independent reviewers selected the studies and extracted the data. Results were expressed as relative risk (RR) or mean differences (MDs) with 95% confidence intervals (CIs). Seven hundred fifty-one studies were identified between 1946 and 2016. After screening, there were 16 randomized controlled clinical trials, including 724 participants, that provided data for the meta-analysis. The methodological reporting of most studies was poor, and appropriate judgment of their individual risk of bias elements was not possible. There was no difference between the 2 drugs regarding the need for conversion to general anesthesia (RR, 0.60; 95% CI, 0.08-4.41; P = .62; I = 0%), incidence of hypotension (RR, 1.15; 95% CI, 0.69-1.92; P = .58; I = 0%), nausea/vomiting (RR, 0.29; 95% CI, 0.06-1.32; P = .11; I = 7%), or onset of sensory block (MD = 1.7 minutes; 95% CI, -3.5 to 0.1; P = .07; I = 0%). The onset of motor block (MD = 4.6 minutes; 95% CI, 7.5-1.7; P = .002; I = 78%) was significantly faster with hyperbaric bupivacaine. Conversely, the duration of motor (MD = 45.2 minutes; 95% CI, 66.3-24.2; P < .001; I = 87%) and sensory (MD = 29.4 minutes; 95% CI, 15.5-43.3; P < .001; I = 73%) block was longer with isobaric bupivacaine. Both hyperbaric bupivacaine and isobaric bupivacaine provided effective anesthesia with no

Reducing the concentration to 0.4% enantiomeric excess hyperbaric levobupivacaine (s75: r25) provides unilateral spinal anesthesia. Study with different volumes.

PubMed

Imbelloni, Luiz Eduardo; Gouveia, Marildo A; Carneiro, Antonio Fernando; Grigorio, Renata

2012-01-01

Unilateral spinal anesthesia may be obtained with hypobaric or hyperbaric solution. The objective of this study was to compare different doses of enantiomeric excess hyperbaric levobupivacaine to achieve unilateral spinal anesthesia. One hundred and twenty patients were randomized to receive 4 mg, 6 mg or 8 mg of 0.4% enantiomeric excess levobupivacaine. The solutions were administered at the L3-L4, with the patient in a lateral position and kept at this position according to dose administration for 5, 10 or 15 minutes. Sensory block (pinprick) and motor block (scale 0-3) were compared between the operated and contralateral sides. The onset of analgesia was rapid and comparable between groups. Sensory block was significantly higher in the operated than in nonoperated limb at all times of evaluation. Increasing the dose by 1 mL (2mg) corresponded to an increase of two segments in the mode for the operated side. In the operated side, motor block (MB = 3) of patients occurred in 31 (77.5%) with 4 mg, 38 (95%) with 6 mg, and 40 (100%) with 8 mg. There was a positive correlation between increased dose, blockade duration, and hypotension. All patients were satisfied with the technique used. Spinal anesthesia with different volumes of enantiomeric excess hyperbaric bupivacaine (S75: R25) provided a 78% incidence of unilateral spinal block, with the smallest dose used (4 mg) the most efficient. Copyright © 2012 Elsevier Editora Ltda. All rights reserved.

Hyperbaric therapy for a postpartum patient with prolonged epidural blockade and tomographic evidence of epidural air.

PubMed

Panni, Moeen K; Camann, William; Bhavani Shankar, Kodali

2003-12-01

We used the epidural technique "loss of resistance to air" to provide labor analgesia in a healthy parturient. Inadequate analgesia required epidural catheter replacement using the same technique. Delayed recovery of sensory and motor blockade postpartum necessitated computed tomography and magnetic resonance imaging studies. These revealed 4-6 mL of air in the epidural space with no evidence of thecal compression. On the advice of the neurologist, this patient underwent hyperbaric therapy 14 h after the discontinuation of the epidural infusion. The patient made a complete recovery and was discharged without neurologic sequelae. It is possible that epidural air delayed the absorption of local anesthetics as a result of a reduction in the vascular surface area. Although a cause and effect relationship between epidural air and prolonged neurological block cannot be categorically established, the use of "loss of resistance to air" technique complicated the differential diagnosis. We report a case of prolonged motor and sensory block after labor analgesia using "loss of resistance to air" technique. The presence of epidural air on tomography resulted in the patient undergoing hyperbaric therapy. The use of loss of resistance to air technique complicated the differential diagnosis of prolonged sensory and motor block.

Cerebral gas embolism due to upper gastrointestinal endoscopy.

PubMed

ter Laan, Mark; Totte, Erik; van Hulst, Rob A; van der Linde, Klaas; van der Kamp, Wim; Pierie, Jean-Pierre E

2009-07-01

Cerebral gas embolism as a result of upper gastrointestinal endoscopy is a rare complication and bares a high morbidity. A patient is presented who underwent an upper endoscopy for evaluation of a gastric-mediastinal fistula after subtotal oesophagectomy and gastric tube reconstruction because of oesophageal cancer. During the procedure, cerebral gas emboli developed resulting in an acute left-sided hemiparesis. After hyperbaric oxygen therapy, the patient recovered almost completely. The aetiology and treatment is discussed based on the reviewed literature. Once cerebral gas emboli are recognized, patient outcome can be improved by hyperbaric oxygen therapy.

Expanded oxygen minimum zones during the late Paleocene-early Eocene: Hints from multiproxy comparison and ocean modeling

NASA Astrophysics Data System (ADS)

Zhou, X.; Thomas, E.; Winguth, A. M. E.; Ridgwell, A.; Scher, H.; Hoogakker, B. A. A.; Rickaby, R. E. M.; Lu, Z.

2016-12-01

Anthropogenic warming could well drive depletion of oceanic oxygen in the future. Important insight into the relationship between deoxygenation and warming can be gleaned from the geological record, but evidence is limited because few ocean oxygenation records are available for past greenhouse climate conditions. We use I/Ca in benthic foraminifera to reconstruct late Paleocene through early Eocene bottom and pore water redox conditions in the South Atlantic and Southern Indian Oceans and compare our results with those derived from Mn speciation and the Ce anomaly in fish teeth. We conclude that waters with lower oxygen concentrations were widespread at intermediate depths (1.5-2 km), whereas bottom waters were more oxygenated at the deepest site, in the Southeast Atlantic Ocean (>3 km). Epifaunal benthic foraminiferal I/Ca values were higher in the late Paleocene, especially at low-oxygen sites, than at well-oxygenated modern sites, indicating higher seawater total iodine concentrations in the late Paleocene than today. The proxy-based bottom water oxygenation pattern agrees with the site-to-site O2 gradient as simulated in a comprehensive climate model (Community Climate System Model Version 3), but the simulated absolute dissolved O2 values are low (< 35 µmol/kg), while higher O2 values ( 60-100 µmol/kg) were obtained in an Earth system model (Grid ENabled Integrated Earth system model). Multiproxy data together with improvements in boundary conditions and model parameterization are necessary if the details of past oceanographic oxygenation are to be resolved.

Oxygen and Oxygen Toxicity: The Birth of Concepts

PubMed Central

Zhu, Hong; Traore, Kassim; Santo, Arben; Trush, Michael A.; Li, Y. Robert

2018-01-01

Molecular dioxygen (O2) is an essential element of aerobic life, yet incomplete reduction or excitation of O2 during aerobic metabolisms generates diverse oxygen-containing reactive species, commonly known as reactive oxygen species (ROS). On the one hand, ROS pose a serious threat to aerobic organisms via inducing oxidative damage to cellular constituents. On the other hand, these reactive species, when their generation is under homeostatic control, also play important physiological roles (e.g., constituting an important component of immunity and participating in redox signaling). This article defines oxygen and the key facts about oxygen, and discusses the relationship between oxygen and the emergence of early animals on Earth. The article then describes the discovery of oxygen by three historical figures and examines the birth of the concepts of oxygen toxicity and the underlying free radical mechanisms. The article ends with a brief introduction to the emerging field of ROS-mediated redox signaling and physiological responses. PMID:29707642

Early cavopulmonary anastomosis in very young infants after the Norwood procedure: impact on oxygenation, resource utilization, and mortality.

PubMed

Jaquiss, Robert D B; Ghanayem, Nancy S; Hoffman, George M; Fedderly, Raymond T; Cava, Joseph R; Mussatto, Kathleen A; Tweddell, James S

2004-04-01

The optimal timing of second-stage palliation after Norwood operations remains undefined. Advantages of early cavopulmonary anastomosis are early elimination of volume load and shortening the high-risk interstage period. Potential disadvantages include severe cyanosis, prolonged pleural drainage and hospitalization, and excess mortality. We reviewed our recent experience to evaluate the safety of early cavopulmonary anastomosis. Eighty-five consecutive patients undergoing post-Norwood operation cavopulmonary anastomosis were divided into group I (cavopulmonary anastomosis at <4 months; n = 33) and group II (cavopulmonary anastomosis at >4 months; n = 52). Groups were compared for age; size; early and late mortality; preoperative, initial postoperative, and discharge oxygen saturation; and duration of mechanical ventilation, intensive care unit stay, pleural drainage, and hospitalization. Group I patients were younger than group II patients (94 +/- 21 days vs 165 +/- 44 days, respectively; P <.001) and smaller (4.8 +/- 0.8 kg vs 5.8 +/- 0.9 kg; P <.001). The preoperative oxygen saturation was not different (group I, 75% +/- 10%; group II, 78% +/- 8%; P =.142). The oxygen saturation was lower immediately after surgery in group I compared with group II (75% +/- 7% vs 81% +/- 7%, respectively; P <.001) but not by discharge (group I, 79% +/- 4%; group II, 80% +/- 4%). Younger patients were ventilated longer (62 +/- 86 hours vs 19 +/- 42 hours; P =.001), in the intensive care unit longer (130 +/- 111 hours vs 104 +/- 94 hours; P =.049), hospitalized longer (12.5 +/- 11.5 days vs 10.3 +/- 14.8 days; P =.012), and required longer pleural drainage (106 +/- 45 hours vs 104 +/- 93 hours; P =.046). Hospital survival was 100% in both groups. Actuarial survival to 12 months was 96% +/- 4% for group I and 96% +/- 3% for group II. Early cavopulmonary anastomosis after the Norwood operation is safe. Younger patients are more cyanotic initially after surgery and have a longer

Hemoglobin phase of oxygenation and deoxygenation in early brain development measured using fNIRS

PubMed Central

Watanabe, Hama; Shitara, Yoshihiko; Aoki, Yoshinori; Inoue, Takanobu; Tsuchida, Shinya; Takahashi, Naoto; Taga, Gentaro

2017-01-01

A crucial issue in neonatal medicine is the impact of preterm birth on the developmental trajectory of the brain. Although a growing number of studies have shown alterations in the structure and function of the brain in preterm-born infants, we propose a method to detect subtle differences in neurovascular and metabolic functions in neonates and infants. Functional near-infrared spectroscopy (fNIRS) was used to obtain time-averaged phase differences between spontaneous low-frequency (less than 0.1 Hz) oscillatory changes in oxygenated hemoglobin (oxy-Hb) and those in deoxygenated hemoglobin (deoxy-Hb). This phase difference was referred to as hemoglobin phase of oxygenation and deoxygenation (hPod) in the cerebral tissue of sleeping neonates and infants. We examined hPod in term, late preterm, and early preterm infants with no evidence of clinical issues and found that all groups of infants showed developmental changes in the values of hPod from an in-phase to an antiphase pattern. Comparison of hPod among the groups revealed that developmental changes in hPod in early preterm infants precede those in late preterm and term infants at term equivalent age but then, progress at a slower pace. This study suggests that hPod measured using fNIRS is sensitive to the developmental stage of the integration of circular, neurovascular, and metabolic functions in the brains of neonates and infants. PMID:28196885

Effects of two fractions of inspired oxygen during anesthesia on early postanesthesia oxygenation in healthy dogs.

PubMed

Martin-Flores, Manuel; Tseng, Chia T; Robillard, Steven D; Abrams, Brittany E; Campoy, Luis; Harvey, H Jay; Gleed, Robin D

2018-02-01

OBJECTIVE To evaluate the effects of 2 fractions of inspired oxygen (Fio 2 s) during anesthesia on postanesthesia Pao 2 and other measures of oxygen exchange. ANIMALS 22 healthy adult sexually intact female dogs undergoing ovariohysterectomy by ventral midline celiotomy. PROCEDURES Dogs were randomly assigned to receive either oxygen (Fio 2 > 0.9 [100% oxygen]; n = 11; control group) or a mixture of nitrogen and oxygen (Fio 2 = 0.4; 11; 40% oxygen group) as the carrier gas for isoflurane while anesthetized. All dogs were allowed to breathe spontaneously while anesthetized. For each dog, the Pao 2 , Paco 2 , other indices of oxygenation, and extent of sedation were monitored at predetermined times during and for 1 hour after anesthesia. Measured variables were compared between the 2 treatment groups and over time within each treatment group. RESULTS None of the measured variables differed significantly between the control and 40% oxygen groups at any time during the postanesthesia period. Within each treatment group, the Paco 2 and extent of sedation decreased over time during the postanesthesia period. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that indices of oxygenation did not differ significantly between healthy dogs in which the Fio 2 was maintained at > 0.9 and those in which the Fio 2 was maintained at 0.4 while anesthetized for ovariohysterectomy. Thus, the addition of nitrogen to the carrier gas for an inhalant anesthetic conferred neither an advantage nor disadvantage in regard to oxygenation during the first hour of anesthesia recovery.

Problems Associated with Meaningful Research on the Effects of Hyperbaric Oxygen on Mycotic Disease Agents.

DTIC Science & Technology

1980-02-01

USAFA-TR-A-NL mhmmmhhhhhhhIEhhhhhEEEEa IIIIII. iiiii ,_oi ,o 虡 11112. 41. 111IL25 MICROCOPY RESOLUTION TEST C *AT NATIONAL BUREAU Or ST/fl) ARDS-1963-0...UNCLASSIFIED SCCUftIlY CLASSIFICATION OF T-40 PA@ C (Vhm Data Rateri.) USAPA-TR-80-4 PROBLE1S ASSOCIATED WITH MEANINGFUL RESEARCH ON THE EFFECTS OF...correlations (or non-correlations) of susceptibility of certain fungal taxa to inhibition by increased oxygen levels, c ) questionable reliability of results of

Oxygen and hydrogen peroxide in the early evolution of life on earth: in silico comparative analysis of biochemical pathways.

PubMed

Slesak, Ireneusz; Slesak, Halina; Kruk, Jerzy

2012-08-01

In the Universe, oxygen is the third most widespread element, while on Earth it is the most abundant one. Moreover, oxygen is a major constituent of all biopolymers fundamental to living organisms. Besides O(2), reactive oxygen species (ROS), among them hydrogen peroxide (H(2)O(2)), are also important reactants in the present aerobic metabolism. According to a widely accepted hypothesis, aerobic metabolism and many other reactions/pathways involving O(2) appeared after the evolution of oxygenic photosynthesis. In this study, the hypothesis was formulated that the Last Universal Common Ancestor (LUCA) was at least able to tolerate O(2) and detoxify ROS in a primordial environment. A comparative analysis was carried out of a number of the O(2)-and H(2)O(2)-involving metabolic reactions that occur in strict anaerobes, facultative anaerobes, and aerobes. The results indicate that the most likely LUCA possessed O(2)-and H(2)O(2)-involving pathways, mainly reactions to remove ROS, and had, at least in part, the components of aerobic respiration. Based on this, the presence of a low, but significant, quantity of H(2)O(2) and O(2) should be taken into account in theoretical models of the early Archean atmosphere and oceans and the evolution of life. It is suggested that the early metabolism involving O(2)/H(2)O(2) was a key adaptation of LUCA to already existing weakly oxic zones in Earth's primordial environment.

[Fatal air embolism during open eye surgery].

PubMed

Dermigny, F; Daelman, F; Guinot, P-G; Hubert, V; Jezraoui, P; Thomas, F; Milazzo, S; Dupont, H

2008-10-01

Gas embolism is well known for a specific subset of surgical interventions. Prevention and early detection are the main objectives of the anesthetic and surgical team. However, it may exceptionally occur during eye surgery with dramatic outcomes. We report the case of a 51-year-old man, ASA physical status 1, who presented a cardiac arrest during an open eye surgery for the extraction of a foreign body with intraocular air injection. Multiple organ failure has not been improved by hyperbaric oxygen therapy and the outcome was fatal.

29 CFR Appendix A to Subpart Y of... - Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 8 2010-07-01 2010-07-01 false Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions A Appendix A to Subpart Y of Part 1926 Labor Regulations Relating to Labor... REGULATIONS FOR CONSTRUCTION Diving Pt. 1926, Subpt. Y, App. A Appendix A to Subpart Y of Part 1926—Examples...

Eustachian tube function and middle ear barotrauma associated with extremes in atmospheric pressure.

PubMed

Miyazawa, T; Ueda, H; Yanagita, N

1996-11-01

Eustachian tube (ET) function was studied by means of sonotubometry and tubotympano-aerodynamography (TTAG) prior to and following exposure to hypobaric or hyperbaric conditions. Forty normal adults were subjected to hypobaric pressure. Fifty adults who underwent hyperbaric oxygen (HBO) therapy also were studied. Following hypobaric exposure, 14 of 80 ears (17.5%) exhibited middle ear barotrauma. Following hyperbaric exposure, 34 of 100 ears (34%) exhibited middle ear barotrauma. Dysfunction of the ET, characterized by altered active and passive opening capacity, was more prevalent following exposure to extremes in atmospheric pressure compared to baseline. The ET function, which was impaired after the first HBO treatment, improved gradually over the next 2 hours. Overall, however, ET function was worse after the seventh treatment. The patients who developed barotrauma exhibited worse ET function prior to hypobaric or hyperbaric exposure. Thus, abnormal ET function can be used to predict middle ear barotrauma prior to exposure to hypobaric or hyperbaric atmospheric pressure.

Influence of lateral decubitus positioning after combined use of hyperbaric and hypobaric ropivacaine on hemodynamic characteristics in spinal anesthesia for caesarean section.

PubMed

Quan, Zhe-Feng; He, Hai-Li; Tian, Ming; Chi, Ping; Li, Xin

2014-01-01

Positioning of the patient during and after surgery can have significant implications on recovery. Therefore, the purpose of the present study was to determine the influence of placing patients in a lateral decubitus position for 15 min after combined use of hyperbaric and hypobaric ropivacaine and assess hemodynamic characteristics during spinal anesthesia for caesarean section. One hundred-forty patients undergoing elective cesarean delivery with combined use of hyperbaric and hypobaric ropivacaine were included in the present study. Patients meeting inclusion criteria (134) were randomly allocated into Group A: immediately turned to the supine position after induction of spinal anesthesia (n = 67) or Group B: maintained in a lateral decubitus position for 15 min before being turned to the supine position (n = 67). Primary endpoints of the study were to compare hemodynamic characteristics and sensory blockade levels in the two groups, while a secondary endpoint was to observe the incidence of complications. Both groups showed similar effects of the combined anesthetic treatment. Incidence of hypotension (43% vs 18%, P = 0.001), systolic AP < 90 mmHg (36% vs. 16%, P = 0.011), usage of ephedrine (43% vs. 18%, P = 0.001) and the total dose of ephedrine [0 (0-24) vs 0 (0-18), P = 0.001] were significantly higher in Group A compared to Group B. Group A had a higher incidence of nausea compared to Group B (25% vs 7%, P = 0.005). Combined use of hyperbaric and hypobaric ropivacaine had satisfactory anesthetic effects and a more stable hemodynamic characteristic than either drug used alone. Maintaining the patient in a lateral decubitus position for 15 min can significantly decrease the incidence of hypotension.

Efficacy of 0.5% Hyperbaric Bupivacaine with Dexamethasone versus 0.5% Hyperbaric Bupivacaine alone in Spinal Anaesthesia for Patient Undergoing Lower Abdominal Urological and Lower Limb Orthopedic Surgeries.

PubMed

Haque, M M; Aleem, M A; Haque, F H; Siddique, A B; Afrose, R

2018-04-01

Spinal anaesthesia with local anaesthetics has limited duration. Different additives have been used to prolong spinal anaesthesia. The aim of this study was to determine the efficacy of adding dexamethasone to bupivacaine in spinal anaesthesia specially whether it would prolong the duration of sensory block/ surgical analgesia and post-operative analgesia/pain free period or not. This randomized, prospective, double-blind, clinical study was conducted in the Department of Anaesthesia, Analgesia and Critical Care of Combined Military Hospital, Chittagong from October 2016 to August 2017. Seventy two (72) adult patients scheduled for lower abdominal urological and lower limb orthopedic surgery under spinal anaesthesia were included. They were divided in two groups; each group comprised 36 patients to receive 20mg 0.5% hyperbaric bupivacaine (Bupivacaine group) or 15mg 0.5% hyperbaric bupivacaine plus 5mg dexamethasone (Bupivacaine-Dexamethasone/case group) intrathecally. The patients were evaluated for quality, quantity and duration of sensory block/surgical analgesia, post-operative analgesia/pain free period, blood pressure, heart rate, nausea, and vomiting or other complications. There were no significant differences in demographic data, sensory level and onset time of the sensory block between two groups. Duration of sensory block/Surgical analgesia in the bupivacaine group was 92.32±8.34 minutes and in the bupivacaine- dexamethasone/case group was 122.11±10.59 minutes which was statistically highly significant (p<0.001). The duration of post-operative analgesia/pain free period was 208.78±41.57 minutes in the bupivacaine group; whereas it was 412.82±71.51 minutes in the bupivacaine-dexamethasone/case group which was also statistically highly significant (p<0.001). The frequency of complications was not different between two groups. This study has shown that the addition of dexamethasone to bupivacaine in spinal anaesthesia significantly improved the duration

Posture-related distribution of hyperbaric bupivacaine in cerebro-spinal fluid is influenced by spinal needle characteristics.

PubMed

Mardirosoff, C; Dumont, L; Deyaert, M; Leconte, M

2001-07-01

No studies have evaluated the relationship between duration of time sitting and spinal needle type on the maximal spread of local anaesthetics. The few trials available have studied the influence of time spent sitting on the spread of anaesthesia without standardising spinal needle types, and have not found any effect. In this randomised, blinded study, 60 patients scheduled for elective orthopaedic surgery of the lower limbs were divided into 4 groups. With the patient sitting erect, 15 mg hyperbaric bupivacaine were injected in a standard manner through a 24G Sprotte or a 27G Whitacre needle and patients were placed supine after 1 min (24G/1 group and 27G/1 group) or 4 min (24G/4 group and 27G/4 group). Time to achieve maximum block height after injection was similar in all groups. Block height levels were significantly lower at all time points for the 24G/4 group. Maximum block heights were Th4 in the 24G/1, 27G/1 and 27G/4 groups, and Th6 in the 24G/4 group (P<0.0001). In a standard spinal anaesthesia procedure, when different lengths of time spent sitting are compared, spinal needle characteristics influence the maximum spread of hyperbaric bupivacaine. However, within the limits of our study, a two-segment difference in block height is too small to consider using spinal needles as valuable tools to control block height during spinal anaesthesia in our daily practice.

Influence of In Vitro and In Vivo Oxygen Modulation on β Cell Differentiation From Human Embryonic Stem Cells

PubMed Central

Cechin, Sirlene; Álvarez-Cubela, Silvia; Giraldo, Jaime A.; Molano, Ruth D.; Villate, Susana; Ricordi, Camillo; Pileggi, Antonello; Inverardi, Luca

2014-01-01

The possibility of using human embryonic stem (hES) cell-derived β cells as an alternative to cadaveric islets for the treatment of type 1 diabetes is now widely acknowledged. However, current differentiation methods consistently fail to generate meaningful numbers of mature, functional β cells. In order to address this issue, we set out to explore the role of oxygen modulation in the maturation of pancreatic progenitor (PP) cells differentiated from hES cells. We have previously determined that oxygenation is a powerful driver of murine PP differentiation along the endocrine lineage of the pancreas. We hypothesized that targeting physiological oxygen partial pressure (pO2) levels seen in mature islets would help the differentiation of PP cells along the β-cell lineage. This hypothesis was tested both in vivo (by exposing PP-transplanted immunodeficient mice to a daily hyperbaric oxygen regimen) and in vitro (by allowing PP cells to mature in a perfluorocarbon-based culture device designed to carefully adjust pO2 to a desired range). Our results show that oxygen modulation does indeed contribute to enhanced maturation of PP cells, as evidenced by improved engraftment, segregation of α and β cells, body weight maintenance, and rate of diabetes reversal in vivo, and by elevated expression of pancreatic endocrine makers, β-cell differentiation yield, and insulin production in vitro. Our studies confirm the importance of oxygen modulation as a key variable to consider in the design of β-cell differentiation protocols and open the door to future strategies for the transplantation of fully mature β cells. PMID:24375542

Necrotizing fasciitis as a complication of odontogenic infection: a review of management and case series.

PubMed

Bayetto, K; Cheng, A; Sambrook, P

2017-09-01

The aims of the present study were to establish the incidence of head and neck necrotizing fasciitis (NF) in the Adelaide Oral and Maxillofacial Surgery Unit; review the current literature regarding the management of head and neck NF; and determine the evidence for the role of hyperbaric oxygen therapy in the management of NF. A retrospective audit of all patients admitted to the Royal Adelaide Hospital Oral and Maxillofacial Surgery Unit 2006-2015 with severe odontogenic infections was carried out. Patient demographics were recorded and treatment details were collected and analysed. A total of 672 patients were admitted for management of severe odontogenic infections. Of these, three were identified as NF. One case was treated using hyperbaric oxygen as an adjunct to conventional surgical and medical management. Two cases were managed using aggressive surgical management alone. Two patients survived. The incidence of head and neck NF in South Australia is 48/100 000 infections per year. The first-line treatment of severe odontogenic infections remains conventional surgical and medical management; however, hyperbaric oxygen therapy may have an additional role in the management of NF and other rare severe infections in medically complex patients. © 2017 Australian Dental Association.

Temporomandibular joint involvement as a positive clinical prognostic factor in necrotising external otitis.

PubMed

Yeheskeli, E; Eta, R Abu; Gavriel, H; Kleid, S; Eviatar, E

2016-05-01

Necrotising otitis externa is associated with high morbidity and mortality rates. This study investigated whether temporomandibular joint involvement had any prognostic effect on the course of necrotising otitis externa in patients who had undergone hyperbaric oxygen therapy after failed medical and sometimes surgical therapy. A retrospective case series was conducted of patients in whom antibiotic treatment and surgery had failed, who had been hospitalised for further treatment and hyperbaric oxygen therapy. Twenty-three patients with necrotising otitis externa were identified. The temporomandibular joint was involved in four patients (17 per cent); these patients showed a constant gradual improvement in C-reactive protein and were eventually discharged free of disease, except one patient who was lost to follow up. Four patients (16 per cent) without temporomandibular joint involvement died within 90 days of discharge, while all patients with temporomandibular joint involvement were alive. Three patients (13 per cent) without temporomandibular joint involvement needed recurrent hospitalisation including further hyperbaric oxygen therapy; no patients with temporomandibular joint involvement required such treatment. Patients with temporomandibular joint involvement had lower rates of recurrent disease and no mortality. Therefore, we suggest considering temporomandibular joint involvement as a positive prognostic factor in necrotising otitis externa management.

Decompression Sickness and U-2 Operations: Summary of Research, Findings, and Recommendations Regarding Use of Exercise During Prebreathe

DTIC Science & Technology

2010-03-01

Research Laboratory Hypobaric DCS Research Database developed at Brooks AFB, TX, which has detailed information on over 3,000 research chamber... hyperbaric oxygen therapy resulting in complete resolution of all symptoms. After instituting EDP, the same pilot flew 36 U-2 high flights without any...consultation with base SGP and USAFSAM Hyperbarics and MAJCOM/SGPA. Earlier guidance in the 1980’s was much more restrictive and, in fact, permanently

[Evaluation of spinal anesthesia blockade time with 0.5% hyperbaric bupivacaine, with or without sufentanil, in chronic opioid users: a randomized clinical trial].

PubMed

Sadeghi, Mostafa; Yekta, Reza Atef; Azimaraghi, Omid; Barzin, Gilda; Movafegh, Ali

2016-01-01

The primary outcome of this study was to evaluate the effect of adding sufentanil to hyperbaric bupivacaine on duration of sensory blockade of spinal anesthesia in chronic opioid users in comparison with non-addicts. Sixty patients scheduled for orthopedic surgery under spinal anesthesia were allocated into four groups: group 1 (no history of opium use who received intrathecal hyperbaric bupivacaine along with 1mL saline as placebo); group 2 (no history of opium use who received intrathecal bupivacaine along with 1mL sufentanil [5μg]); group 3 (positive history of opium use who received intrathecal bupivacaine along with 1mL saline as placebo) and group 4 (positive history of opium use who received intrathecal bupivacaine along with 1mL sufentanil [5μg]). The onset time and duration of sensory and motor blockade were measured. The duration of sensory blockade in group 3 was 120±23.1min which was significantly less than other groups (G1=148±28.7, G2=144±26.4, G4=139±24.7, p=0.007). The duration of motor blockade in group 3 was 145±30.0min which was significantly less than other groups (G1=164±36.0, G2=174±26.8, G4=174±24.9, p=0.03). Addition of 5μg intrathecal sufentanil to hyperbaric bupivacaine in chronic opioid users lengthened the sensory and motor duration of blockade to be equivalent to blockade measured in non-addicts. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

Evaluation of spinal anesthesia blockade time with 0.5% hyperbaric bupivacaine, with or without sufentanil, in chronic opioid users: a randomized clinical trial.

PubMed

Sadeghi, Mostafa; Yekta, Reza Atef; Azimaraghi, Omid; Barzin, Gilda; Movafegh, Ali

2016-01-01

The primary outcome of this study was to evaluate the effect of adding sufentanil to hyperbaric bupivacaine on duration of sensory blockade of spinal anesthesia in chronic opioid users in comparison with non-addicts. Sixty patients scheduled for orthopedic surgery under spinal anesthesia were allocated into four groups: group 1 (no history of opium use who received intrathecal hyperbaric bupivacaine along with 1mL saline as placebo); group 2 (no history of opium use who received intrathecal bupivacaine along with 1mL sufentanil [5μg]); group 3 (positive history of opium use who received intrathecal bupivacaine along with 1mL saline as placebo) and group 4 (positive history of opium use who received intrathecal bupivacaine along with 1mL sufentanil [5μg]). The onset time and duration of sensory and motor blockade were measured. The duration of sensory blockade in group 3 was 120±23.1min which was significantly less than other groups (G1=148±28.7, G2=144±26.4, G4=139±24.7, p=0.007). The duration of motor blockade in group 3 was 145±30.0min which was significantly less than other groups (G1=164±36.0, G2=174±26.8, G4=174±24.9, p=0.03). Addition of 5μg intrathecal sufentanil to hyperbaric bupivacaine in chronic opioid users lengthened the sensory and motor duration of blockade to be equivalent to blockade measured in non-addicts. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

Influence of lateral decubitus positioning after combined use of hyperbaric and hypobaric ropivacaine on hemodynamic characteristics in spinal anesthesia for caesarean section

PubMed Central

Quan, Zhe-Feng; He, Hai-Li; Tian, Ming; Chi, Ping; Li, Xin

2014-01-01

Purpose: Positioning of the patient during and after surgery can have significant implications on recovery. Therefore, the purpose of the present study was to determine the influence of placing patients in a lateral decubitus position for 15 min after combined use of hyperbaric and hypobaric ropivacaine and assess hemodynamic characteristics during spinal anesthesia for caesarean section. Methods: One hundred-forty patients undergoing elective cesarean delivery with combined use of hyperbaric and hypobaric ropivacaine were included in the present study. Patients meeting inclusion criteria (134) were randomly allocated into Group A: immediately turned to the supine position after induction of spinal anesthesia (n = 67) or Group B: maintained in a lateral decubitus position for 15 min before being turned to the supine position (n = 67). Primary endpoints of the study were to compare hemodynamic characteristics and sensory blockade levels in the two groups, while a secondary endpoint was to observe the incidence of complications. Results: Both groups showed similar effects of the combined anesthetic treatment. Incidence of hypotension (43% vs 18%, P = 0.001), systolic AP < 90 mmHg (36% vs. 16%, P = 0.011), usage of ephedrine (43% vs. 18%, P = 0.001) and the total dose of ephedrine [0 (0-24) vs 0 (0-18), P = 0.001] were significantly higher in Group A compared to Group B. Group A had a higher incidence of nausea compared to Group B (25% vs 7%, P = 0.005). Conclusions: Combined use of hyperbaric and hypobaric ropivacaine had satisfactory anesthetic effects and a more stable hemodynamic characteristic than either drug used alone. Maintaining the patient in a lateral decubitus position for 15 min can significantly decrease the incidence of hypotension. PMID:25664088

Mo isotope record of shales points to deep ocean oxygenation in the early Paleoproterozoic

NASA Astrophysics Data System (ADS)

Asael, Dan; Scott, Clint; Rouxel, Olivier; Poulton, Simon; Lyons, Timothy; Javaux, Emmanuelle; Bekker, Andrey

2014-05-01

Two steps in Earth's surface oxidation lie at either end of the Proterozoic Eon. The first step, known as the Great Oxidation Event (GOE), occurred at ca. 2.32 Ga (1), when atmospheric oxygen first exceeded 0.001% of present atmospheric levels (2). The second step, occurred at ca. 0.58 Ga, resulting in the pervasive oxygenation of the deep oceans, a feature that persisted through most of the Phanerozoic (3). The conventional model envisions two progressive and unidirectional increases in free oxygen. However, recent studies have challenged this simplistic view of the GOE (4, 5). A dramatic increase and decline in Earth oxidation state between 2.3 and 2.0 Ga is now well supported (6-9) and raises the question of how well-oxygenated the Earth surface was in the immediate aftermath of the GOE. In order to constrain the response of the deep oceans to the GOE, we present a study of Mo isotope composition and Mo concentration from three key early Paleoproterozoic black shale units with ages ranging from 2.32 to 2.06 Ga. Our results suggest high and unstable surface oxygen levels at 2.32 Ga, leading to an abrupt increase in Mo supply to the still globally anoxic ocean, and producing extreme seawater Mo isotopic enrichments in these black shales. We thus infer a period of significant Mo isotopic Rayleigh effects and non-steady state behaviour of the Mo oceanic system at the beginning of the GOE. Between 2.2-2.1 Ga, we observe smaller Mo isotopic variations and estimate the δ98Mo of seawater to be 1.42 ± 0.27 ‰W conclude that oxygen levels must have stabilized at a relatively high level and that the deep oceans were oxygenated for the first time in Earth's history. By ca. 2.06 Ga, immediately after the Lomagundi Event, the Mo isotopic composition decreased dramatically to δ98MoSW = 0.80 ± 0.21 o reflecting the end of deep ocean oxygenation and the return of largely anoxic deep oceans. References: [1] A. Bekker et al., 2004, Nature 427, 117-20. [2] A. Pavlov and J

Timescales of Oxygenation Following the Evolution of Oxygenic Photosynthesis

NASA Astrophysics Data System (ADS)

Ward, Lewis M.; Kirschvink, Joseph L.; Fischer, Woodward W.

2016-03-01

Among the most important bioenergetic innovations in the history of life was the invention of oxygenic photosynthesis—autotrophic growth by splitting water with sunlight—by Cyanobacteria. It is widely accepted that the invention of oxygenic photosynthesis ultimately resulted in the rise of oxygen by ca. 2.35 Gya, but it is debated whether this occurred more or less immediately as a proximal result of the evolution of oxygenic Cyanobacteria or whether they originated several hundred million to more than one billion years earlier in Earth history. The latter hypothesis involves a prolonged period during which oxygen production rates were insufficient to oxidize the atmosphere, potentially due to redox buffering by reduced species such as higher concentrations of ferrous iron in seawater. To examine the characteristic timescales for environmental oxygenation following the evolution of oxygenic photosynthesis, we applied a simple mathematical approach that captures many of the salient features of the major biogeochemical fluxes and reservoirs present in Archean and early Paleoproterozoic surface environments. Calculations illustrate that oxygenation would have overwhelmed redox buffers within ~100 kyr following the emergence of oxygenic photosynthesis, a geologically short amount of time unless rates of primary production were far lower than commonly expected. Fundamentally, this result arises because of the multiscale nature of the carbon and oxygen cycles: rates of gross primary production are orders of magnitude too fast for oxygen to be masked by Earth's geological buffers, and can only be effectively matched by respiration at non-negligible O2 concentrations. These results suggest that oxygenic photosynthesis arose shortly before the rise of oxygen, not hundreds of millions of years before it.

Timescales of Oxygenation Following the Evolution of Oxygenic Photosynthesis.

PubMed

Ward, Lewis M; Kirschvink, Joseph L; Fischer, Woodward W

2016-03-01

Among the most important bioenergetic innovations in the history of life was the invention of oxygenic photosynthesis-autotrophic growth by splitting water with sunlight-by Cyanobacteria. It is widely accepted that the invention of oxygenic photosynthesis ultimately resulted in the rise of oxygen by ca. 2.35 Gya, but it is debated whether this occurred more or less immediately as a proximal result of the evolution of oxygenic Cyanobacteria or whether they originated several hundred million to more than one billion years earlier in Earth history. The latter hypothesis involves a prolonged period during which oxygen production rates were insufficient to oxidize the atmosphere, potentially due to redox buffering by reduced species such as higher concentrations of ferrous iron in seawater. To examine the characteristic timescales for environmental oxygenation following the evolution of oxygenic photosynthesis, we applied a simple mathematical approach that captures many of the salient features of the major biogeochemical fluxes and reservoirs present in Archean and early Paleoproterozoic surface environments. Calculations illustrate that oxygenation would have overwhelmed redox buffers within ~100 kyr following the emergence of oxygenic photosynthesis, a geologically short amount of time unless rates of primary production were far lower than commonly expected. Fundamentally, this result arises because of the multiscale nature of the carbon and oxygen cycles: rates of gross primary production are orders of magnitude too fast for oxygen to be masked by Earth's geological buffers, and can only be effectively matched by respiration at non-negligible O2 concentrations. These results suggest that oxygenic photosynthesis arose shortly before the rise of oxygen, not hundreds of millions of years before it.

Hypoxia, Color Vision Deficiencies, and Blood Oxygen Saturation

DTIC Science & Technology

2013-11-01

Richalet, Duval-Arnould, Darnaud, Keromes, & Rutgers, 1988; Richalet et al., 1989; Brandl & Lachenmayr, 1994; Schellart, Pollen , & van der Kley...60, 105-111. Schellart, N.A., Pollen , M. & van der Kley, A. (1997). Effect of dysoxia and moderate air-hyperbarism on red-green color sensitivity

Topical oxygen therapy promotes the healing of chronic diabetic foot ulcers: a pilot study.

PubMed

Hayes, P D; Alzuhir, N; Curran, G; Loftus, I M

2017-11-02

Interventions that can heal or reduce diabetic foot ulcer (DFU) size may reduce the incidence of infection and amputation, and reduce associated social and economic costs. Many chronic wounds exhibit a degree of hypoxia and this leads to a reduction in healing processes including cell division and differentiation, angiogenesis, infection prevention, and collagen production. The aim of this pilot study was to assess the effects of a device supplying continuous oxygen ambulatory therapy on healing in chronic DFUs. Patients with chronic DFUs from two tertiary referral hospitals in the UK received treatment with the device. Data were prospectively obtained on wound size using standardised digital images measured by a clinician blinded to the study. Data on device satisfaction and pain were also obtained. We recruited 10 patients, with a mean ulcer duration of 43 weeks (median: 43 weeks) before treatment. By week eight, mean ulcer size had decreased by 51% (median: 53%). Seven of the 10 ulcers were in a healing trajectory, one ulcer present for 56 weeks healed completely, a two-year old ulcer was reduced by more than 50%, and a third, present for 88 weeks, was down to 10% of its original size by the end of the eight-week study. There was also a non-significant trend towards reduction in pain and the device was extremely well tolerated. The ambulatory topical oxygen delivery device showed a significant beneficial effect on wound size. This poses practical advantages over currently existing oxygen-based wound therapies such as hyperbaric oxygen therapy due to its continuous oxygen delivery, ease of use, safety and lower cost. The results of this study warrant further review of the device in comparison to standard wound therapies.

Low oxygen tension enhances endothelial fate of human pluripotent stem cells.

PubMed

Kusuma, Sravanti; Peijnenburg, Elizabeth; Patel, Parth; Gerecht, Sharon

2014-04-01

A critical regulator of the developing or regenerating vasculature is low oxygen tension. Precise elucidation of the role of low oxygen environments on endothelial commitment from human pluripotent stem cells necessitates controlled in vitro differentiation environments. We used a feeder-free, 2-dimensional differentiation system in which we could monitor accurately dissolved oxygen levels during human pluripotent stem cell differentiation toward early vascular cells (EVCs). We found that oxygen uptake rate of differentiating human pluripotent stem cells is lower in 5% O2 compared with atmospheric conditions. EVCs differentiated in 5% O2 had an increased vascular endothelial cadherin expression with clusters of vascular endothelial cadherin+ cells surrounded by platelet-derived growth factor β+ cells. When we assessed the temporal effects of low oxygen differentiation environments, we determined that low oxygen environments during the early stages of EVC differentiation enhance endothelial lineage commitment. EVCs differentiated in 5% O2 exhibited an increased expression of vascular endothelial cadherin and CD31 along with their localization to the membrane, enhanced lectin binding and acetylated low-density lipoprotein uptake, rapid cord-like structure formation, and increased expression of arterial endothelial cell markers. Inhibition of reactive oxygen species generation during the early stages of differentiation abrogated the endothelial inductive effects of the low oxygen environments. Low oxygen tension during early stages of EVC derivation induces endothelial commitment and maturation through the accumulation of reactive oxygen species, highlighting the importance of regulating oxygen tensions during human pluripotent stem cell-vascular differentiation.

Early oxygenation of the terrestrial environment during the Mesoproterozoic.

PubMed

Parnell, John; Boyce, Adrian J; Mark, Darren; Bowden, Stephen; Spinks, Sam

2010-11-11

Geochemical data from ancient sedimentary successions provide evidence for the progressive evolution of Earth's atmosphere and oceans. Key stages in increasing oxygenation are postulated for the Palaeoproterozoic era (∼2.3 billion years ago, Gyr ago) and the late Proterozoic eon (about 0.8 Gyr ago), with the latter implicated in the subsequent metazoan evolutionary expansion. In support of this rise in oxygen concentrations, a large database shows a marked change in the bacterially mediated fractionation of seawater sulphate to sulphide of Δ(34)S < 25‰ before 1 Gyr to ≥50‰ after 0.64 Gyr. This change in Δ(34)S has been interpreted to represent the evolution from single-step bacterial sulphate reduction to a combination of bacterial sulphate reduction and sulphide oxidation, largely bacterially mediated. This evolution is seen as marking the rise in atmospheric oxygen concentrations and the evolution of non-photosynthetic sulphide-oxidizing bacteria. Here we report Δ(34)S values exceeding 50‰ from a terrestrial Mesoproterozoic (1.18 Gyr old) succession in Scotland, a time period that is at present poorly characterized. This level of fractionation implies disproportionation in the sulphur cycle, probably involving sulphide-oxidizing bacteria, that is not evident from Δ(34)S data in the marine record. Disproportionation in both red beds and lacustrine black shales at our study site suggests that the Mesoproterozoic terrestrial environment was sufficiently oxygenated to support a biota that was adapted to an oxygen-rich atmosphere, but had also penetrated into subsurface sediment.

A favorable outcome despite a 39-hour treatment delay for arterial gas embolism: case report.

PubMed

Covington, Derek; Bielawski, Anthony; Sadler, Charlotte; Latham, Emi

2016-01-01

Cerebral arterial gas embolism (CAGE) occurs when gas enters the cerebral arterial vasculature. CAGE can occur during sitting craniotomies, cranial trauma or secondary to gas embolism from the heart. A far less common cause of CAGE is vascular entrainment of gas during endoscopic procedures. We present the case of a 49-year-old male who developed a CAGE following an esophagoduodenoscopy (EGD) biopsy. Due to a delay in diagnosis, the patient was not treated with hyperbaric oxygen (HBO₂) therapy until 39 hours after the inciting event. Despite presenting to our institution non-responsive and with decorticate posturing, the patient was eventually discharged to a rehabilitation facility, with only mild left upper extremity weakness. This delay in HBO₂ treatment represents the longest delay in treatment to our knowledge for a patient suffering from CAGE secondary to EGD. In addition to the clinical case report, we discuss the etiology of CAGE and the evidence supporting early HBO₂ treatment, as well as the data demonstrating efficacy even after considerable treatment delay. Copyright© Undersea and Hyperbaric Medical Society.

Nanophase Iron Oxides as an Ultraviolet Sunscreen for Ancient Photosynthetic Microbes: A Possible Link Between Early Organisms, Banded-Iron Formations, and the Oxygenation of the Atmosphere

NASA Technical Reports Server (NTRS)

Bishop, Janice L.; Rothschild, Lynn J.; Rothschild, Lynn J.; Rogoff, Dana A.

2006-01-01

We propose that nanophase iron oxide-bearing materials provided important niches for ancient photosynthetic microbes on the early Earth that ultimately led to the oxygenation of the Earth s atmosphere and the formation of iron oxide deposits. Atmospheric oxygen and ozone attenuate UV radiation on the Earth today providing substantial protection for photosynthetic organisms. With ultraviolet radiation fluxes likely to have been even higher on the early Earth than today, accessing solar radiation was particularly risky for early organisms. Yet, we know that photosynthesis arose then and played a critical role in subsequent evolution. Of primary importance was protection at approx.250-290 nm, where peak nucleic acid (approx.260 nm) and protein (approx.280 nm) absorptions occur. Nanophase ferric oxide/oxyhydroxide minerals absorb, and thus block, the lethal UV radiation, while transmitting light through much of the visible and near-infrared regions of interest to photosynthesis (400 to 1100 nm). Further, they were available in early environments, and are synthesized by many organisms. Based on ferric oxide/oxyhydroxide spectral properties, likely geologic processes, and the results of experiments with the photosynthetic organisms, Euglena sp. and Chlumydomonus reinhardtii, we propose a scenario where photosynthesis, and ultimately the oxygenation of the atmosphere, depended on the protection of early microbes by nanophase ferric oxides/oxyhydroxides. The results of this study are also applicable to other potentially habitable iron-bearing planetary bodies because of the evolutionary pressure to utilize solar radiation when available as an energy source.

Regulation of myogenesis and skeletal muscle regeneration: effects of oxygen levels on satellite cell activity.

PubMed

Chaillou, Thomas; Lanner, Johanna T

2016-12-01

Reduced oxygen (O 2 ) levels (hypoxia) are present during embryogenesis and exposure to altitude and in pathologic conditions. During embryogenesis, myogenic progenitor cells reside in a hypoxic microenvironment, which may regulate their activity. Satellite cells are myogenic progenitor cells localized in a local environment, suggesting that the O 2 level could affect their activity during muscle regeneration. In this review, we present the idea that O 2 levels regulate myogenesis and muscle regeneration, we elucidate the molecular mechanisms underlying myogenesis and muscle regeneration in hypoxia and depict therapeutic strategies using changes in O 2 levels to promote muscle regeneration. Severe hypoxia (≤1% O 2 ) appears detrimental for myogenic differentiation in vitro, whereas a 3-6% O 2 level could promote myogenesis. Hypoxia impairs the regenerative capacity of injured muscles. Although it remains to be explored, hypoxia may contribute to the muscle damage observed in patients with pathologies associated with hypoxia (chronic obstructive pulmonary disease, and peripheral arterial disease). Hypoxia affects satellite cell activity and myogenesis through mechanisms dependent and independent of hypoxia-inducible factor-1α. Finally, hyperbaric oxygen therapy and transplantation of hypoxia-conditioned myoblasts are beneficial procedures to enhance muscle regeneration in animals. These therapies may be clinically relevant to treatment of patients with severe muscle damage.-Chaillou, T. Lanner, J. T. Regulation of myogenesis and skeletal muscle regeneration: effects of oxygen levels on satellite cell activity. © FASEB.

Alteration of striatal dopamine levels under various partial pressure of oxygen in pre-convulsive and convulsive phases in freely-moving rats.

PubMed

Lavoute, Cécile; Weiss, Michel; Risso, Jean-Jacques; Rostain, Jean-Claude

2014-02-01

The purpose of this study was to investigate the change in the striatal dopamine (DA) level in freely-moving rat exposed to different partial pressure of oxygen (from 1 to 5 ATA). Some works have suggested that DA release by the substantia nigra pars compacta (SNc) neurons in the striatum could be disturbed by hyperbaric oxygen (HBO) exposure, altering therefore the basal ganglia activity. Such changes could result in a change in glutamatergic and GABAergic control of the dopaminergic neurons into the SNc. Such alterations could provide more information about the oxygen-induced seizures observed at 5 ATA in rat. DA-sensitive electrodes were implanted into the striatum under general anesthesia. After 1 week rest, awaked rats were exposed to oxygen-nitrogen mixture at a partial pressure of oxygen of 1, 2, 3, 4 and 5 ATA. DA level was monitored continuously (every 3 min) by in vivo voltammetry before and during HBO exposure. HBO induced a decrease in DA level in relationship to the increase in partial pressure of oxygen from 1 ATA to 4 ATA (-15 % at 1 ATA, -30 % at 2 ATA, -40 % at 3 ATA, -45 % at 4 ATA), without signs of oxygen toxicity. At 5 ATA, DA level strongly decreases (-75 %) before seizure which occurred after 27 min ± 7 HBO exposure. After the epileptic seizure the decrease in DA level disappeared. These changes and the biphasic effect of HBO were discussed in function of HBO action on neurochemical regulations of the nigro striatal pathway.

Cost and mortality data of a regional limb salvage and hyperbaric medicine program for Wagner Grade 3 or 4 diabetic foot ulcers.

PubMed

Eggert, J V; Worth, E R; Van Gils, C C

2016-01-01

We obtained costs and mortality data in two retrospective cohorts totaling 159 patients who have diabetes mellitus and onset of a diabetic foot ulcer (DFU). Data were collected from 2005 to 2013, with a follow-up period through September 30, 2014. A total of 106 patients entered an evidence-based limb salvage protocol (LSP) for Wagner Grade 3 or 4 (WG3/4) DFU and intention-to-treat adjunctive hyperbaric oxygen (HBO₂) therapy. A second cohort of 53 patients had a primary lower extremity amputation (LEA), either below the knee (BKA) or above the knee (AKA) and were not part of the LSP. Ninety-six of 106 patients completed the LSP/HBO₂with an average cost of USD $33,100. Eighty-eight of 96 patients (91.7%) who completed the LSP/HBO₂had intact lower extremities at one year. Thirty-four of the 96 patients (35.4%) died during the follow-up period. Costs for a historical cohort of 53 patients having a primary major LEA range from USD $66,300 to USD $73,000. Twenty-five of the 53 patients (47.2%) died. The difference in cost of care and mortality between an LSP with adjunctive HBO₂therapy vs. primary LEA is staggering. We conclude that an aggressive limb salvage program that includes HBO₂ therapy is cost-effective.

Noninvasive oxygen monitoring techniques.

PubMed

Wahr, J A; Tremper, K K

1995-01-01

As this article demonstrates, tremendous progress has been made in the techniques of oxygen measurement and monitoring over the past 50 years. From the early developments during and after World War II, to the most recent applications of solid state and microprocessor technology today, every patient in a critical care situation will have several continuous measurements of oxygenation applied simultaneously. Information therefore is available readily to alert personnel of acute problems and to guide appropriate therapy. The majority of effort to date has been placed on measuring oxygenation of arterial or venous blood. The next generation of devices will attempt to provide information about living tissue. Unlike the devices monitoring arterial or venous oxygen content, no "gold standards" exist for tissue oxygenation, so calibration will be difficult, as will interpretation of the data provided. The application of these devices ultimately may lead to a much better understanding of how disease (and the treatment of disease) alters the utilization of oxygen by the tissues.

Oxygen therapy reduces secondary hemorrhage after thrombolysis in thromboembolic cerebral ischemia.

PubMed

Sun, Li; Zhou, Wei; Mueller, Christian; Sommer, Clemens; Heiland, Sabine; Bauer, Alexander T; Marti, Hugo H; Veltkamp, Roland

2010-09-01

Hyperbaric oxygen (HBO) and normobaric hyperoxia (NBO) protect the brain parenchyma and the cerebral microcirculation against ischemia. We studied their effect on secondary hemorrhage after thrombolysis in two thromboembolic middle cerebral artery occlusion (MCAO) (tMCAO) models. Beginning 60 minutes after tMCAO with either thrombin-induced thromboemboli (TT) or calcium-induced thromboemboli (CT), spontaneously hypertensive rats (n=96) breathed either air, 100% O(2) (NBO), or 100% O(2) at 3 bar (HBO) for 1 hour. Immediately thereafter, recombinant tissue plasminogen activator (rt-PA, 9 mg/kg) was injected. Although significant reperfusion was observed after thrombolysis in TT-tMCAO, vascular occlusion persisted in CT-tMCAO. In TT-tMCAO, NBO and HBO significantly reduced diffusion-weighted imaging-magnetic resonance imaging (MRI) lesion volume and postischemic blood-brain barrier (BBB) permeability on postcontrast T1-weighted images. NBO and, significantly more potently, HBO reduced macroscopic hemorrhage on T2* MRI and on corresponding postmortem cryosections. Oxygen therapy lowered hemoglobin content and attenuated activation of matrix metalloproteinases in the ischemic hemisphere. In contrast, NBO and HBO failed to reduce infarct size in CT but both decreased BBB damage and microscopic hemorrhagic transformation. Only HBO reduced hemoglobin extravasation in the ischemic hemisphere. In conclusion, NBO and HBO decrease infarct size after thromboembolic ischemia only if recanalization is successful. As NBO and HBO also reduce postthrombolytic intracerebral hemorrhage, combining the two with thrombolysis seems promising.

Isotopic Composition of Oxygen in Lunar Zircons

NASA Technical Reports Server (NTRS)

Nemchin, A. A.; Whitehouse, M. J.; Pidgeon, R. T.; Meyer, C.

2005-01-01

The recent discovery of heavy oxygen in zircons from the Jack Hills conglomerates Wilde et al. and Mojzsis et al. was interpreted as an indication of presence of liquid water on the surface of Early Earth. The distribution of ages of Jack Hills zircons and lunar zircons appears to be very similar and therefore analysis of oxygen in the lunar grains may provide a reference frame for further study of the early history of the Earth as well as give additional information regarding processes that operated on the Moon. In the present study we have analysed the oxygen isotopic composition of zircon grains from three lunar samples using the Swedish Museum of Natural History CAMECA 1270 ion microprobe. The samples were selected as likely tests for variations in lunar oxygen isotopic composition. Additional information is included in the original extended abstract.

Oceanic oxygenation events in the anoxic Ediacaran ocean.

PubMed

Sahoo, S K; Planavsky, N J; Jiang, G; Kendall, B; Owens, J D; Wang, X; Shi, X; Anbar, A D; Lyons, T W

2016-09-01

The ocean-atmosphere system is typically envisioned to have gone through a unidirectional oxygenation with significant oxygen increases in the earliest (ca. 635 Ma), middle (ca. 580 Ma), or late (ca. 560 Ma) Ediacaran Period. However, temporally discontinuous geochemical data and the patchy metazoan fossil record have been inadequate to chart the details of Ediacaran ocean oxygenation, raising fundamental debates about the timing of ocean oxygenation, its purported unidirectional rise, and its causal relationship, if any, with the evolution of early animal life. To better understand the Ediacaran ocean redox evolution, we have conducted a multi-proxy paleoredox study of a relatively continuous, deep-water section in South China that was paleogeographically connected with the open ocean. Iron speciation and pyrite morphology indicate locally euxinic (anoxic and sulfidic) environments throughout the Ediacaran in this section. In the same rocks, redox sensitive element enrichments and sulfur isotope data provide evidence for multiple oceanic oxygenation events (OOEs) in a predominantly anoxic global Ediacaran-early Cambrian ocean. This dynamic redox landscape contrasts with a recent view of a redox-static Ediacaran ocean without significant change in oxygen content. The duration of the Ediacaran OOEs may be comparable to those of the oceanic anoxic events (OAEs) in otherwise well-oxygenated Phanerozoic oceans. Anoxic events caused mass extinctions followed by fast recovery in biologically diversified Phanerozoic oceans. In contrast, oxygenation events in otherwise ecologically monotonous anoxic Ediacaran-early Cambrian oceans may have stimulated biotic innovations followed by prolonged evolutionary stasis. © 2016 John Wiley & Sons Ltd.

Fate of abstracts presented at the annual scientific meeting of the Undersea and Hyperbaric Medical Society.

PubMed

Uzun, Günalp; Mutluoğlu, Mesut; Bakir, Alev; Senocak, Mustafa S

2013-01-01

The full-text publication of abstracts presented at any given scientific meeting in peer-reviewed journals is accepted as a measure of scientific quality of that particular meeting. The aim of this study is to determine the full-text publication rate of abstracts presented at the 2005 Scientific Meeting of the Undersea and Hyperbaric Medical Society (UHMS). We identified the scientific abstracts presented at the 2005 UHMS meeting and searched the PubMed database (June 2005 to July 2010) for their corresponding full-text publication. We recorded the following parameters for each of the abstracts: number of authors, number of centers involved in the study, statistical methods used, country of origin of the study, study type, and subject of the abstract. We recorded the time to publication and the title of the journal if the abstract had been published in a peer-reviewed journal. Overall, we identified 187 abstracts presented at the 2005 UHMS meeting. Two of the abstracts were excluded from the study because they had been retracted from the meeting and six more because they had been already published as full-text articles at the time the meeting was held. Of the 179 abstracts, 62 (34.6%) were published as full-text articles within the succeeding five years. The mean (+/- SD) time to publication was 18.5 (+/- 13.6) months. Multivariate analysis with logistic regression identified "country of origin" and "the subject of the abstract" as independent predictors of full-text publication. We found that only one-third of the abstracts presented at the 2005 UHMS meeting were published as full-text articles within the succeeding five years. Although this rate is consistent with similar studies from various disciplines, further research is needed to identify the specific barriers to full-text publication of abstracts in the field of underwater and hyperbaric medicine.

Optimal intrathecal hyperbaric bupivacaine dose with opioids for cesarean delivery: a prospective double-blinded randomized trial.

PubMed

Onishi, Eiko; Murakami, Mamoru; Hashimoto, Keiji; Kaneko, Miho

2017-05-01

Single-shot spinal anesthesia is commonly used for cesarean delivery. Achieving adequate anesthesia throughout surgery needs to be balanced with associated complications. We investigated the optimal dose of intrathecal hyperbaric bupivacaine, co-administered with opioids, for anesthesia for cesarean delivery. This prospective, randomized, double-blinded, dose-ranging trial included parturients scheduled to undergo cesarean delivery under spinal anesthesia. An epidural catheter was first inserted at the T11-12 vertebral interspace, followed by spinal anesthesia at the L2-3 or L3-4 vertebral interspace. Subjects were randomly assigned to one of seven doses of intrathecal hyperbaric bupivacaine 0.5% (6, 7, 8, 9, 10, 11 or 12mg), with added 15μg fentanyl and 75μg morphine. Successful induction of anesthesia (success ind ) was defined as achievement of bilateral sensory loss to cold at the T6 dermatome or higher, within 10 minutes. Successful maintenance of anesthesia (success main ) was defined by no epidural supplementation within 60 minutes of intrathecal injection. The effective doses for 50% (ED 50 ) and 95% (ED 95 ) of patients were estimated using logistic regression analysis. The ED 50 and ED 95 for success main were 6.0mg (95% CI: 4.5 to 7.5mg) and 12.6mg (95% CI: 7.9 to 17.2mg), respectively. The incidence of respiratory discomfort and maternal satisfaction scores did not differ significantly between dose groups. Phenylephrine dose and nausea/vomiting incidence increased with increasing doses of bupivacaine. Under study conditions, our results suggest that 12.6mg of intrathecal bupivacaine, administered with fentanyl and morphine, is required to achieve adequate intraoperative analgesia without the need for epidural supplemention. Copyright © 2017 Elsevier Ltd. All rights reserved.

Involvement of reactive oxygen species during early stages of ectomycorrhiza establishment between Castanea sativa and Pisolithus tinctorius.

PubMed

Baptista, Paula; Martins, Anabela; Pais, Maria Salomé; Tavares, Rui M; Lino-Neto, Teresa

2007-05-01

Evidence for the participation of reactive oxygen species (ROS) and antioxidant systems in ectomycorrhizal (ECM) establishment is lacking. In this paper, we evaluated ROS production and the activities of superoxide dismutase (SOD) and catalase (CAT) during the early contact of the ECM fungus Pisolithus tinctorius with the roots of Castanea sativa (chestnut tree). Roots were placed in contact with P. tinctorius mycelia, and ROS production was evaluated by determining the levels of H(2)O(2) and O(2) (.-) during the early stages of fungal contact. Three peaks of H(2)O(2) production were detected, the first two coinciding with O(2) (.-) bursts. The first H(2)O(2) production peak coincided with an increase in SOD activity, whereas CAT activity seemed to be implicated in H(2)O(2) scavenging. P. tinctorius growth was evaluated in the presence of P. tinctorius-elicited C. sativa crude extracts prepared during the early stages of fungal contact. Differential hyphal growth that matched the H(2)O(2) production profile with a delay was detected. The result suggests that during the early stages of ECM establishment, H(2)O(2) results from an inhibition of ROS-scavenging enzymes and plays a role in signalling during symbiotic establishment.

Oxygen as a driver of early arthropod micro-benthos evolution.

PubMed

Williams, Mark; Vannier, Jean; Corbari, Laure; Massabuau, Jean-Charles

2011-01-01

We examine the physiological and lifestyle adaptations which facilitated the emergence of ostracods as the numerically dominant Phanerozoic bivalve arthropod micro-benthos. The PO(2) of modern normoxic seawater is 21 kPa (air-equilibrated water), a level that would cause cellular damage if found in the tissues of ostracods and much other marine fauna. The PO(2) of most aquatic breathers at the cellular level is much lower, between 1 and 3 kPa. Ostracods avoid oxygen toxicity by migrating to waters which are hypoxic, or by developing metabolisms which generate high consumption of O(2). Interrogation of the Cambrian record of bivalve arthropod micro-benthos suggests a strong control on ecosystem evolution exerted by changing seawater O(2) levels. The PO(2) of air-equilibrated Cambrian-seawater is predicted to have varied between 10 and 30 kPa. Three groups of marine shelf-dwelling bivalve arthropods adopted different responses to Cambrian seawater O(2). Bradoriida evolved cardiovascular systems that favoured colonization of oxygenated marine waters. Their biodiversity declined during intervals associated with black shale deposition and marine shelf anoxia and their diversity may also have been curtailed by elevated late Cambrian (Furongian) oxygen-levels that increased the PO(2) gradient between seawater and bradoriid tissues. Phosphatocopida responded to Cambrian anoxia differently, reaching their peak during widespread seabed dysoxia of the SPICE event. They lacked a cardiovascular system and appear to have been adapted to seawater hypoxia. As latest Cambrian marine shelf waters became well oxygenated, phosphatocopids went extinct. Changing seawater oxygen-levels and the demise of much of the seabed bradoriid micro-benthos favoured a third group of arthropod micro-benthos, the ostracods. These animals adopted lifestyles that made them tolerant of changes in seawater O(2). Ostracods became the numerically dominant arthropod micro-benthos of the Phanerozoic. Our work

Oxygen as a Driver of Early Arthropod Micro-Benthos Evolution

PubMed Central

Williams, Mark; Vannier, Jean; Corbari, Laure; Massabuau, Jean-Charles

2011-01-01

Background We examine the physiological and lifestyle adaptations which facilitated the emergence of ostracods as the numerically dominant Phanerozoic bivalve arthropod micro-benthos. Methodology/Principal Findings The PO2 of modern normoxic seawater is 21 kPa (air-equilibrated water), a level that would cause cellular damage if found in the tissues of ostracods and much other marine fauna. The PO2 of most aquatic breathers at the cellular level is much lower, between 1 and 3 kPa. Ostracods avoid oxygen toxicity by migrating to waters which are hypoxic, or by developing metabolisms which generate high consumption of O2. Interrogation of the Cambrian record of bivalve arthropod micro-benthos suggests a strong control on ecosystem evolution exerted by changing seawater O2 levels. The PO2 of air-equilibrated Cambrian-seawater is predicted to have varied between 10 and 30 kPa. Three groups of marine shelf-dwelling bivalve arthropods adopted different responses to Cambrian seawater O2. Bradoriida evolved cardiovascular systems that favoured colonization of oxygenated marine waters. Their biodiversity declined during intervals associated with black shale deposition and marine shelf anoxia and their diversity may also have been curtailed by elevated late Cambrian (Furongian) oxygen-levels that increased the PO2 gradient between seawater and bradoriid tissues. Phosphatocopida responded to Cambrian anoxia differently, reaching their peak during widespread seabed dysoxia of the SPICE event. They lacked a cardiovascular system and appear to have been adapted to seawater hypoxia. As latest Cambrian marine shelf waters became well oxygenated, phosphatocopids went extinct. Changing seawater oxygen-levels and the demise of much of the seabed bradoriid micro-benthos favoured a third group of arthropod micro-benthos, the ostracods. These animals adopted lifestyles that made them tolerant of changes in seawater O2. Ostracods became the numerically dominant arthropod micro-benthos of