Read the full article here: http://www.torontosun.com/2012/05/19/hyperbaric-oxygen-therapy-debate-thrives

Brain Res. 2011 Jul 21;1402:109-21

Authors: Yan W, Zhang H, Bai X, Lu Y, Dong H, Xiong L

Abstract Our previous studies have demonstrated that hyperbaric oxygen (HBO) preconditioning induces tolerance to focal cerebral ischemia. The present study aimed to investigate whether autophagy is involved in the neuroprotection elicited by HBO preconditioning in a rat model of transient focal cerebral ischemia. Twenty-four hours after the completion of HBO preconditioning (2.5 atm absolute in 100% oxygen for 60 min per day for 5 consecutive days), male Sprague-Dawley rats were subjected to focal cerebral ischemia by middle cerebral artery occlusion (MCAO) for 120 min. The neurobehavioral score and infarct volume were used to evaluate cerebral ischemic injury. An intracerebroventricular injection of the autophagy inhibitor 3-methyladenine (3-MA) or the autophagy inducer rapamycin was administered before HBO preconditioning or MCAO. We found that after reperfusion the protein expression of LC3-II and Beclin 1 and the formation of autophagosomes were increased by HBO preconditioning or ischemia, but the increase following HBO preconditioning was higher than the increase following ischemia. 3-MA suppressed the increases in LC3-II and Beclin 1 induced by HBO preconditioning and attenuated the neuroprotection of HBO preconditioning against cerebral ischemia. Furthermore, 3-MA treatment before MCAO aggravated subsequent cerebral ischemic injury. In contrast, pretreatment with rapamycin up-regulated LC3-II and Beclin 1 after reperfusion and mimicked the neuroprotective effect of HBO preconditioning. These results indicate that HBO preconditioning elevates autophagic activity, which elicits a neuroprotective effect against ischemic injury in the brain, and suggest a novel mechanism of HBO preconditioning-induced tolerance against transient focal cerebral ischemia.

PMID: 21684529 [PubMed - indexed for MEDLINE]

Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?tmpl=NoSidebarfile&db=PubMed&cmd=Retrieve&list_uids=21684529&dopt=Abstract

Zhonghua Xue Ye Xue Za Zhi. 2011 Jun;32(6):419-20

Authors: Zhang W, Chen BA, Bao W

PMID: 21781505 [PubMed - indexed for MEDLINE]

Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?tmpl=NoSidebarfile&db=PubMed&cmd=Retrieve&list_uids=21781505&dopt=Abstract

Eur J Clin Invest. 2012 Mar;42(3):260-5

Authors: Keramidas ME, Norman B, Gustafsson T, Eiken O, Mekjavic IB

Abstract BACKGROUND: Based on a report of a marked increase in the erythropoietin concentration ([EPO]) a few hours after the cessation of a single 2-h session of O(2) breathing, short periods of O(2) administration have been advocated as a therapy for anaemia. Accordingly, the purpose of the present study was to evaluate this theory by investigating the effect of 10 daily short-term exposures to normobaric O(2) over a 2-week period on the plasma [EPO] in healthy individuals. MATERIAL AND METHODS: Twenty men were assigned to either an experimental (NBO(2)) or to a control (AIR) group. The NBO(2) group breathed 100% normobaric O(2) for 2 h every weekday over a 2-week period. The AIR group breathed air within the same time protocol. Blood samples were collected at the pre-, mid- and post-intervention periods to determine [EPO]. RESULTS: [EPO] of the NBO(2) group was significantly lower than that of the AIR group during the mid- and post-periods (P < 0·001). [EPO] of the NBO(2) group showed a slight, albeit statistically nonsignificant, decrease during the mid (∼11%)- and post (∼16%)-periods. CONCLUSIONS: Daily short-term exposures to normobaric hyperoxia do not increase the [EPO] in healthy individuals. The increased O(2) tension suppresses [EPO]. Hence, administration of pure O(2) to enhance erythropoiesis is not warranted.

PMID: 21834800 [PubMed - indexed for MEDLINE]

Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?tmpl=NoSidebarfile&db=PubMed&cmd=Retrieve&list_uids=21834800&dopt=Abstract

Diabetes Metab Res Rev. 2012 Feb;28 Suppl 1:64-71

Authors: Gottrup F, Apelqvist J

Abstract Management of foot ulcer in individuals with diabetes remains a major therapeutic challenge throughout the world. We performed a critical review of evidence of present and new techniques and devices in the treatment of diabetic foot ulcer. The golden standard for optimal evidence in the Cochrane system is level I - randomized controlled trials, and meta-analyses of several randomized controlled trials. Available evidence on different types of wound debridement; use of antimicrobials; use of dressings in wounds; topical negative pressure, hyperbaric oxygen treatment; electrical, electromagnetic, laser, shockwave, and ultrasound therapies; growth and cell biology factors; cell products and tissue engineering; bioengineered skin and skin grafts; and adjuvant therapies were evaluated. The results of this review show that there is limited evidence on the highest level to justify a change in routine clinical practice. There is a paucity of high-quality evidence, because the studies are often based on inadequate sample size, short follow-up, nonrandom allocation to treatment arms, nonblinded assessment of outcomes, poor description of control, and concurrent intervention. The heterogeneity of the population (of both people and ulcers), with multiple factors contributing to both ulcer onset and failure to heal, makes the trial design difficult in this field. Another fundamental reason for the lack of evidence is the general use of the outcome measure 'complete healing'. In conclusion, when the results of this updated review are taken together with those of the earlier reports, they provide limited evidence to justify a change in routine clinical practice. For this reason, there is an urgent need to increase the quality of clinical studies. A re-evaluation of which type of research is acceptable for producing evidence in the wound area may be important in the future.

PMID: 22271726 [PubMed - indexed for MEDLINE]

Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?tmpl=NoSidebarfile&db=PubMed&cmd=Retrieve&list_uids=22271726&dopt=Abstract

Clin Toxicol (Phila). 2012 Apr;50(4):271-2

Authors: Karydes H, Bryant SM

PMID: 22455360 [PubMed - indexed for MEDLINE]

Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?tmpl=NoSidebarfile&db=PubMed&cmd=Retrieve&list_uids=22455360&dopt=Abstract

Med Gas Res. 2012 May 11;2(1):13

Authors: Ghanizadeh A

Abstract ABSTRACT: There is a controversy about the efficacy of hyperbaric oxygen (HBO) therapy for the treatment of autism. This study systematically reviews the current evidences for treating of autism with HBO therapy. According to PRISMA guidelines for a systematic review, the databases of MEDLINE/Pubmed, Google Scholar, and Randomised Controlled Trials in Hyperbaric Medicine were electronically searched. In addition, medical subject heading terms and text words for hyperbaric oxygen therapy and autism were used. The main inclusion criteria were published studies which reported the original data from the trials conducted on the patients with autism and assessed outcomes with a valid and reliable instrument. A quality assessment was also conducted. The electronically search resulted in 18 title of publications. Two studies were randomized, double-blind, controlled-clinical trials. While some uncontrolled and controlled studies suggested that HBO therapy is effective for the treatment of autism, these promising effects are not replicated. Therefore, sham-controlled studies with rigorous methodology are required to be conducted in order to provide scientific evidence-based HBO therapy for autism treatment.

PMID: 22577817 [PubMed - as supplied by publisher]

Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?tmpl=NoSidebarfile&db=PubMed&cmd=Retrieve&list_uids=22577817&dopt=Abstract

Cochrane Database Syst Rev. 2012;5:CD005277

Authors: Bennett MH, Lehm JP, Mitchell SJ, Wasiak J

Abstract BACKGROUND: Decompression illness (DCI) is due to bubble formation in the blood or tissues following the breathing of compressed gas. Clinically, DCI may range from a trivial illness to loss of consciousness, death or paralysis. Recompression is the universally accepted standard treatment of DCI. When recompression is delayed, a number of strategies have been suggested in order to improve the outcome. OBJECTIVES: To examine the effectiveness and safety of both recompression and adjunctive therapies in the treatment of DCI. SEARCH METHODS: In our previous update we searched until October 2009. In this version we searched CENTRAL (The Cochrane Library, October 2011); MEDLINE (1966 to October 2011); CINAHL (1982 to October 2011); EMBASE (1980 to October 2011); the Database of Randomised Controlled Trials in Hyperbaric Medicine (October 2011); and handsearched journals and texts. SELECTION CRITERIA: We included randomized controlled trials that compared the effect of any recompression schedule or adjunctive therapy with a standard recompression schedule. We did not apply language restrictions. DATA COLLECTION AND ANALYSIS: Three authors extracted the data independently. We assessed each trial for internal validity and resolved differences by discussion. Data were entered into RevMan 5.1. MAIN RESULTS: Two randomized controlled trials enrolling a total of 268 patients satisfied the inclusion criteria. The risk of bias for Drewry 1994 was unclear as this study was presented as an abstract, while Bennett 2003 was rated as at low risk. Pooling of data was not possible. In one study there was no evidence of improved effectiveness with the addition of a non-steroidal anti-inflammatory drug (tenoxicam) to routine recompression therapy (at six weeks: relative risk (RR) 1.04, 95% confidence interval (CI) 0.90 to 1.20, P = 0.58) but there was a reduction in the number of compressions required when tenoxicam was added from three to two (P = 0.01, 95% CI 0 to 1). In the other study, the odds of multiple recompressions were lower with a helium and oxygen (heliox) table compared to an oxygen treatment table (RR 0.56, 95% CI 0.31 to 1.00, P = 0.05). AUTHORS' CONCLUSIONS: Recompression therapy is standard for the treatment of DCI, but there is no randomized controlled trial evidence for its use. Both the addition of a non-steroidal anti-inflammatory drug (NSAID) and the use of heliox may reduce the number of recompressions required, but neither improve the odds of recovery. The application of either of these strategies may be justified. The modest number of patients studied demands a cautious interpretation. Benefits may be largely economic and an economic analysis should be undertaken. There is a case for large randomized trials of high methodological rigour in order to define any benefit from the use of different breathing gases and pressure profiles during recompression therapy.

PMID: 22592704 [PubMed - in process]

Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?tmpl=NoSidebarfile&db=PubMed&cmd=Retrieve&list_uids=22592704&dopt=Abstract

Cochrane Database Syst Rev. 2012;5:CD005005

Authors: Bennett MH, Feldmeier J, Hampson N, Smee R, Milross C

Abstract BACKGROUND: Cancer is a significant global health problem. Radiotherapy is a treatment for many cancers and about 50% of patients having radiotherapy with be long-term survivors. Some will experience late radiation tissue injury (LRTI) developing months or years later. Hyperbaric oxygen therapy (HBOT) has been suggested as a treatment for LRTI based upon the ability to improve the blood supply to these tissues. It is postulated that HBOT may result in both healing of tissues and the prevention of problems following surgery. OBJECTIVES: To assess the benefits and harms of HBOT for treating or preventing LRTI. SEARCH METHODS: In March 2011 we updated the searches of the Cochrane Central Register of Controlled Trials (CENTRAL), (The Cochrane Library, Issue 1), MEDLINE, EMBASE, DORCTIHM and reference lists of articles. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing the effect of HBOT versus no HBOT on LRTI prevention or healing. DATA COLLECTION AND ANALYSIS: Three review authors independently evaluated the quality of the relevant trials using the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions and extracted the data from the included trials. MAIN RESULTS: Eleven trials contributed to this review (669 participants). For pooled analyses, investigation of heterogeneity suggested important variability between trials but there was some evidence that HBOT is more likely to achieve mucosal coverage with osteoradionecrosis (ORN) (risk ratio (RR) 1.3; 95% confidence interval (CI) 1.1 to 1.6, P = 0.003, number needed to treat for an additional beneficial outcome (NNTB) 5). From single studies there was a significantly increased chance of improvement or cure following HBOT for radiation proctitis (RR 1.72; 95% CI 1.0 to 2.9, P = 0.04, NNTB 5), and following both surgical flaps (RR 8.7; 95% CI 2.7 to 27.5, P = 0.0002, NNTB = 4) and hemimandibulectomy (RR 1.4; 95% CI 1.1 to 1.8, P = 0.001, NNTB 5). There was also a significantly improved probability of healing irradiated tooth sockets following dental extraction (RR 1.4; 95% CI 1.1 to 1.7, P = 0.009, NNTB 4).There was no evidence of benefit in clinical outcomes with established radiation injury to neural tissue, and no data reported on the use of HBOT to treat other manifestations of LRTI. These trials did not report adverse effects. AUTHORS' CONCLUSIONS: These small trials suggest that for people with LRTI affecting tissues of the head, neck, anus and rectum, HBOT is associated with improved outcome. HBOT also appears to reduce the chance of ORN following tooth extraction in an irradiated field. There was no such evidence of any important clinical effect on neurological tissues. The application of HBOT to selected patients and tissues may be justified. Further research is required to establish the optimum patient selection and timing of any therapy. An economic evaluation should be undertaken.

PMID: 22592699 [PubMed - in process]

Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?tmpl=NoSidebarfile&db=PubMed&cmd=Retrieve&list_uids=22592699&dopt=Abstract

ScientificWorldJournal. 2012;2012:573410

Authors: Giannone FA, Treré D, Domenicali M, Grattagliano I, Baracca A, Sgarbi G, Maggioli C, Longobardi P, Solaini G, Derenzini M, Bernardi M, Caraceni P

Abstract Purpose. Hypothermic machine perfusion systems seem more effective than the current static storage to prevent cold ischemic liver injury. Thus, we test an innovative hyperbaric hypothermic machine perfusion (HHMP), which combines hyperbaric oxygenation of the preservation solution and continuous perfusion of the graft. Methods. Rat livers were preserved with Celsior solution according to 4 different modalities: normobaric static preservation; hyperbaric static preservation at 2 atmosphere absolute (ATA); normobaric dynamic preservation, with continuous perfusion; hyperbaric dynamic preservation, with continuous perfusion at 2 ATA. After 24 h cold preservation, we assessed different parameters. Results. Compared to baseline, livers preserved with the current static storage showed severe ultrastructural damage, glycogen depletion and an increased oxidative stress. Normobaric perfused livers showed improved hepatocyte ultrastructure and ameliorated glycogen stores, but they still suffered a significant oxidative damage. The addition of hyperbaric oxygen produces an extra benefit by improving oxidative injury and by inducing endothelial NO synthase (eNOS) gene expression. Conclusions. Preservation by means of the present innovative HHMP reduced the liver injury occurring after the current static cold storage by lowering glycogen depletion and oxidative damage. Interestingly, only the use of hyperbaric oxygen was associated to a blunted oxidative stress and an increased eNOS gene expression.

PMID: 22593698 [PubMed - in process]

Source: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?tmpl=NoSidebarfile&db=PubMed&cmd=Retrieve&list_uids=22593698&dopt=Abstract