Effects of Hyperbaric Oxygen Therapy on Mitochondrial Respiration and Physical Performance in Middle-Aged Athletes: A Blinded, Randomized Controlled Trial.

INTRODUCTION: Hyperbaric oxygen therapy (HBOT) has been used to increase endurance performance but has yet to be evaluated in placebo-controlled clinical trials. The current study aimed to evaluate the effect of an intermittent HBOT protocol on maximal physical performance and mitochondrial function in middle-aged master athletes. METHODS: A double-blind, randomized, placebo-controlled study on 37 healthy middle-aged (40-50) master athletes was performed between 2018 and 2020. The subjects were exposed to 40 repeated sessions of either HBOT [two absolute atmospheres (ATA), breathing 100% oxygen for 1 h] or SHAM (1.02ATA, breathing air for 1 h). RESULTS: Out of 37 athletes, 16 HBOT and 15 SHAM allocated athletes were included in the final analysis. Following HBOT, there was a significant increase in the maximal oxygen consumption (VO2Max) (p = 0.010, effect size(es) = 0.989) and in the oxygen consumption measured at the anaerobic threshold (VO2AT)(es = 0.837) compared to the SHAM group. Following HBOT, there were significant increases in both maximal oxygen phosphorylation capacity (es = 1.085, p = 0.04), maximal uncoupled capacity (es = 0.956, p = 0.02) and mitochondrial mass marker MTG (p = 0.0002) compared to the SHAM sessions. CONCLUSION: HBOT enhances physical performance in healthy middle-age master athletes, including VO2max, power and VO2AT. The mechanisms may be related to significant improvements in mitochondrial respiration and increased mitochondrial mass. Trial Registration ClinicalTrials.gov Identifier: https://clinicaltrials.gov/ct2/show/NCT03524989 (May 15, 2018).

The effect of hyperbaric oxygen therapy on the pathophysiology of skin aging: a prospective clinical trial.

INTRODUCTION: Skin biopsies can be used to evaluate physiological effects of aging targeted intervention at the tissue/cellular levels. Recent clinical trials have shown that hyperbaric oxygen therapy (HBOT) can target aging hallmarks, including telomere shortening, senescent cells clearance and angiogenesis. The aim of this study was to evaluate the effects of HBOT on the skin of a normal, non-pathological, aging population. METHODS: The study was performed as a prospective clinical trial. After signing informed consent and undergoing baseline evaluations, the subjects were assigned to a three-month control period followed by three months of HBOT daily sessions. Skin biopsies were taken at baseline, after three months of no intervention (control) and 1-2 weeks following the last HBOT session. Trichrome, Orecin, lipofuscin and CD31 staining were used to evaluate collagen fibers, elastic fibers, senescent cells and blood vessels, respectively. RESULTS: Out of the cohort of 70 participants in the normal aging population study, thirteen male patients (age 68.07±2.5y) gave consent for repeated skin biopsies. Following HBOT, there was a significant increase in collagen density (p<0.001, effect size(es)=1.10), elastic fiber length (p<0.0001, es=2.71) and the number of blood vessels (p=0.02, es=1.00). There was a significant decrease in fiber fragmentation (p=0.012) and in tissue senescent cells (p=0.03, es=0.84) post-HBOT. No changes were noted in elastic fiber density or thickness. CONCLUSIONS: The study indicates, for the first time in humans, that HBOT can significantly modulate the pathophysiology of the skin aging in a healthy aging population. The demonstrated mechanisms include angiogenesis and senescent cell clearance.

Hyperbaric oxygen therapy increases telomere length and decreases immunosenescence in isolated blood cells: a prospective trial.

INTRODUCTION: Aging is characterized by the progressive loss of physiological capacity. At the cellular level, two key hallmarks of the aging process include telomere length (TL) shortening and cellular senescence. Repeated intermittent hyperoxic exposures, using certain hyperbaric oxygen therapy (HBOT) protocols, can induce regenerative effects which normally occur during hypoxia. The aim of the current study was to evaluate whether HBOT affects TL and senescent cell concentrations in a normal, non-pathological, aging adult population. METHODS: Thirty-five healthy independently living adults, aged 64 and older, were enrolled to receive 60 daily HBOT exposures. Whole blood samples were collected at baseline, at the 30th and 60th session, and 1-2 weeks following the last HBOT session. Peripheral blood mononuclear cells (PBMCs) telomeres length and senescence were assessed. RESULTS: Telomeres length of T helper, T cytotoxic, natural killer and B cells increased significantly by over 20% following HBOT. The most significant change was noticed in B cells which increased at the 30th session, 60th session and post HBOT by 25.68%±40.42 (p=0.007), 29.39%±23.39 (p=0.0001) and 37.63%±52.73 (p=0.007), respectively. There was a significant decrease in the number of senescent T helpers by -37.30%±33.04 post-HBOT (P<0.0001). T-cytotoxic senescent cell percentages decreased significantly by -10.96%±12.59 (p=0.0004) post-HBOT. In conclusion, the study indicates that HBOT may induce significant senolytic effects including significantly increasing telomere length and clearance of senescent cells in the aging populations.

Cognitive enhancement of healthy older adults using hyperbaric oxygen: a randomized controlled trial.

More than half of community-dwelling individuals sixty years and older express concern about declining cognitive abilities. The current study's aim was to evaluate hyperbaric oxygen therapy (HBOT) effect on cognitive functions in healthy aging adults.A randomized controlled clinical trial randomized 63 healthy adults (>64) either to HBOT(n=33) or control arms(n=30) for three months. Primary endpoint included the general cognitive function measured post intervention/control. Cerebral blood flow (CBF) was evaluated by perfusion magnetic resonance imaging.There was a significant group-by-time interaction in global cognitive function post-HBOT compared to control (p=0.0017). The most striking improvements were in attention (net effect size=0.745) and information processing speed (net effect size=0.788).Voxel-based analysis showed significant cerebral blood flow increases in the HBOT group compared to the control group in the right superior medial frontal gyrus (BA10), right and left supplementary motor area (BA6), right middle frontal gyrus (BA6), left middle frontal gyrus (BA9), left superior frontal gyrus (BA8) and the right superior parietal gyrus (BA7).In this study, HBOT was shown to induce cognitive enhancements in healthy aging adults via mechanisms involving regional changes in CBF. The main improvements include attention, information processing speed and executive functions, which normally decline with aging.

Hyperbaric Oxygen Preconditioning Can Reduce Postabdominoplasty Complications: A Retrospective Cohort Study.

BACKGROUND: Hyperbaric oxygen therapy (HBOT) can improve wound healing and has been found to have positive preconditioning effects in animal models. Among esthetic surgical procedures, abdominoplasty poses the highest rate of postoperative complications. The aim of this study was to evaluate the effect of preoperative HBOT as a preconditioning treatment for expected postsurgical complications. METHODS: We conducted a retrospective cohort study among patients who underwent abdominoplasty at our institute and private practice between January 2012 and November 2017. Patients who received preoperative HBOT were compared with patients who did not receive HBOT. Surgical complication data and demographic, preoperative and postoperative data from patient records were collected. RESULTS: The study included 356 patients. Of them, 83 underwent HBOT preoperatively. Using preoperative HBOT, postoperative complications were significantly reduced from 32.6% (89 patients) to 8.4% (7 patients), P <0.001. Moreover, 17 (6.2%) patients in the comparison group and none in the HBOT group experienced necrosis (P = 0.016). In the multivariate analysis, preoperative HBOT was an independent protective factor against postoperative complications (odds ratio, 0.188; 95% CI, 0.082-0.432; P < 0.001). After propensity score matching, the study results remained the same. CONCLUSIONS: Preoperative HBOT can reduce postoperative complication rate in abdominoplasty patients. Further prospective studies are necessary to validate the findings and characterize patients who benefit the most from this treatment.

Hyperbaric oxygen therapy effects on pulmonary functions: a prospective cohort study.

BACKGROUND: Oxygen toxicity is one potential side effect of hyperbaric oxygen therapy (HBOT). Previous small studies showed mild reductions in pulmonary functions reflecting reductions in small airway conductance after repetitive hyperbaric oxygen sessions. However, there are no updated data with well performed pulmonary tests that address the pulmonary effect of the currently used HBOT protocols. The aim of this study was to evaluate the effect of HBOT on pulmonary functions of patients receiving the currently used HBOT protocol. METHODS: Prospective analysis included patients, 18 years or older, scheduled for 60 daily HBOT sessions between 2016 and 2018. Each session was 90 min of 100% oxygen at 2 ATA with 5 min air breaks every 20 min, 5 days per week. Pulmonary functions, measured at baseline and after HBOT, included forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1) and peak expiratory flow rate (PEF). RESULTS: The mean age was 60.36 ± 15.43 and 62.5% (55/88) were males. Most of the patients (83/88, 94.3%) did not have any pulmonary disease prior to inclusion and 30.7% (27/88) had a history of smoking. Compared to baseline values, at the completion of 60 HBOT sessions, there were no significant changes in FEV1 (0.163), FEV1/FVC ratio (0.953) and FEF25-75% (0.423). There was a statistically significant increase though not clinically relevant increase in FVC (0.1 ± 0.38 l) and PEF (0.5 ± 1.4 l) with a 0.014 and 0.001 respectively. CONCLUSION: Regarding pulmonary functions, repeated hyperbaric oxygen exposure based on the currently used HBOT protocol is safe. Surprisingly, there was a modest non clinically significant though statistically significant improvement in PEF and FVC in the current cohort of patients who were without chronic lung diseases. TRIAL REGISTRATION: Clinicaltrials.gov, trial ID: NCT03754985 , (Nov 2018) Retrospectively registered.

Is There an Association Between Hyperbaric Oxygen Therapy and Improved Outcome of Deep Chemical Peeling? A Randomized Pilot Clinical Study.

BACKGROUND: Phenol chemical peeling (PCP) treatment is associated with prolonged recovery and sustained adverse events. Hyperbaric oxygen therapy (HBOT) is known to accelerate wound healing. The purpose of the current study was to evaluate the effect of HBOT on PCP recovery period and adverse events. METHODS: This is a pilot randomized controlled clinical study. Women following PCP underwent 5 consecutive daily HBOT sessions, compared with PCP alone. Pain, pruritus, erythema, crusting, scaling, and edema were daily evaluated up to 28 days following PCP. Photographs taken on days 14 and 35 following PCP were assessed. Confidence to appear in public was assessed 14 days following PCP. RESULTS: Eight participants equally assigned to HBOT and control groups. Lower severity scores for erythema, scaling, and pruritus were documented in the HBOT group (mean difference 1.19, P = .006; .84, P = .04; and 2.19, P = .001, respectively). Photographic assessment severity score was higher for skin tightness, edema, erythema, crusting, and scaling in the control group on day 14 post PCP (P < .05) and for erythema on day 35 post PCP (P < .05). Epithelialization percentage was higher in the HBOT group on day 14 post PCP compared with controls (98.5% ± 1% vs 94.2% ± 1%; P = .021). The HBOT group scored higher in confidence to appear in public (20.8 ± 1.7 vs 14.5 ± 1.3; P = .029). CONCLUSION: Hyperbaric oxygen therapy following PCP is associated with faster recovery as assessed by both patients and caregivers. So far, HBOT was mainly used in the treatment of problematic or chronic wounds. Our study suggests expanding the indications in which hyperbaric oxygen treatment is applicable and recommended.

HISTORIQUE: Le traitement par exfoliation chimique au phénol (ECP) s'associe à une convalescence prolongée et à des événements indésirables soutenus. On sait que l'oxygénothérapie hyperbare (OTHB) accélère la guérison des plaies. La présente étude vise à évaluer l'effet de l'OTHB sur la convalescence et les effets indésirables après une ECP. MÉTHODOLOGIE: Dans le cadre du présent projet pilote clinique aléatoire et contrôlé, des femmes ont suivi cinq séances d'OTHB quotidiennes consécutives auprès une ECP, par rapport à l'ECP seule. Les chercheurs ont évalué la douleur, le prurit, l'érythème, la formation de croûtes, la desquamation et l'œdème tous les jours jusqu'à 28 jours après l'ECP. Ils ont évalué les photos prises les jours 14 et 35 après l'ECP ainsi que la confiance à être vus en public 14 jours après l'ECP. RÉSULTATS: Huit participants participantes ont été réparties également entre l'OTHB et des groupes témoins. Le groupe d'OTHB présentait des scores de gravité plus faibles pour ce qui est de l'érythème, de la desquamation et du prurit (différence moyenne 1,19, P = 0,006; 0,84, P = 0,04; et 2,19; P = 0,001, respectivement). Le score de gravité par évaluation photographique était plus élevé pour ce qui est de l'élasticité de la peau, de l'œdème, de l'érythème, de la formation de croûtes et de la desquamation dans le groupe témoin le jour 14 après l'ECP (P < 0,05) et de l'érythème le jour 35 après l'ECP (P < 0,05). Le pourcentage d'épithélialisation était plus élevé dans le groupe d'OTHB le jour 14 après l'ECP que dans les groupes témoins (98,5 %±1 % par rapport à 94,2 %±1 %, P = 0,021). Le groupe d'OTHB a obtenu des scores de confiance plus élevés à être vus en public (20,8 ± 1,7 par rapport à 14,5 ± 1,3, P = 0,029). CONCLUSION: Selon l'évaluation des patientes et des soignants, l'OTHB s'associe à une convalescence plus rapide après l'ECP. Jusqu'à maintenant, l'OTHB était surtout utilisée pour traiter des plaies problématiques ou chroniques. D'après la présente étude, il est possible d'élargir les indications pour lesquelles l'OTHB est applicable et recommandée.

Correction: Hyperbaric oxygen can induce angiogenesis and recover erectile function.

This has been corrected in both the PDF and HTML versions of the Article.

Hyperbaric oxygen can induce angiogenesis and recover erectile function.

Erectile dysfunction (ED) is caused by microvascular or macrovascular insufficiency in the majority of patients. Recent studies have shown that hyperbaric oxygen therapy (HBOT) can induce angiogenesis in different body organs. The effect of HBOT on the non-surgery-related ED has not been investigated yet. The aim of the current study was to evaluate the effects of HBOT on sexual function and penile vascular bed in non-surgical ED patients. A prospective analysis of patients suffering from chronic ED treated with 40 daily HBOT sessions. Clinical efficacy was assessed using the International Index of Erectile Function questionnaire (IIEF) and a global efficacy question (GEQ). The effect on the penile vascular bed was evaluated by perfusion MRI. Thirty men (mean age of 59.2 ± 1.4) suffering from ED for 4.2 ± 0.6 years completed the protocol. HBOT significantly improved all IIEF domains by 15-88% (p < 0.01). Erectile function improved by 88% (p < 0.0001) and 80% of the patients reported positive outcome according to the GEQ. Angiogenesis was indicated by perfusion MRI that showed a significant increase by 153.3 ± 43.2% of K-trans values in the corpous cavernous (p < 0.0001). HBOT can induce penile angiogenesis and improve erectile function in men suffering from EcD. HBOT reverses the basic common pathophysiology, atherosclerosis and decreased penile perfusion, responsible for most cases of ED.

Reversibility of retinal ischemia due to central retinal artery occlusion by hyperbaric oxygen.

PURPOSE: Ischemic retinal damage can be reversed by hyperbaric oxygen therapy (HBOT) as long as irreversible infarction damage has not developed. However, the time window till irreversible damage develops is still unknown. The study aim was to evaluate the effect of HBOT and determine possible markers for irreversible retinal damage. MATERIALS AND METHODS: Retrospective analysis of 225 patients treated with HBOT for central retinal artery occlusion (CRAO) in 1999-2015. One hundred and twenty-eight patients fulfilled inclusion/exclusion criteria: age >18 years, symptoms <20 hours, and best-corrected visual acuity (BCVA) <0.5 logMAR. RESULTS: Time delay from symptoms to treatment was 7.8±3.8 hours. The BCVA was significantly improved after HBOT, from 2.14±0.50 to 1.61±0.78 (P<0.0001). The proportion of patients with clinically meaningful visual improvement was significantly higher in patients without cherry-red spot (CRS) compared to patients with CRS at presentation (86.0% vs 57.6%, P<0.0001). The percentage of patients with final BCVA better than 1.0 was also significantly higher in patients without CRS vs patients with CRS at presentation (61.0% vs 7.1%, P<0.0001). There was no correlation between CRS and the time from symptoms. HBOT was found to be safe, and only 5.5% of patients had minor, reversible, adverse events. CONCLUSION: HBOT is an effective treatment for non-arteritic CRAO as long as CRS has not formed. The fundus findings, rather than the time delay, should be used as a marker for irreversible damage.

Hyperbaric oxygen therapy can diminish fibromyalgia syndrome--prospective clinical trial.

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 brain activity in pain related areas of FMS patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT01827683.

Delayed recompression for decompression sickness: retrospective analysis.

INTRODUCTION: Most cases of decompression sickness (DCS) occur soon after surfacing, with 98% within 24 hours. Recompression using hyperbaric chamber should be administrated as soon as feasible in order to decrease bubble size and avoid further tissue injury. Unfortunately, there may be a significant time delay from surfacing to recompression. The time beyond which hyperbaric treatment is non effective is unclear. The aims of the study were first to evaluate the effect of delayed hyperbaric treatment, initiated more than 48 h after surfacing for DCS and second, to evaluate the different treatment protocols. METHODS: From January 2000 to February 2014, 76 divers had delayed hyperbaric treatment (≥48 h) for DCS in the Sagol center for Hyperbaric medicine and Research, Assaf-Harofeh Medical Center, Israel. Data were collected from their medical records and compared to data of 128 patients treated earlier than 48 h after surfacing at the same hyperbaric institute. RESULTS: There was no significant difference, as to any of the baseline characteristics, between the delayed and early treatment groups. With respect to treatment results, at the delayed treatment divers, complete recovery was achieved in 76% of the divers, partial recovery in 17.1% and no improvement in 6.6%. Similar results were achieved when treatment started early, where 78% of the divers had complete recovery, 15.6% partial recovery and 6.2% no recovery. Delayed hyperbaric treatment using US Navy Table 6 protocol trended toward a better clinical outcome yet not statistically significant (OR=2.786, CI95%[0.896-8.66], p=0.07) compared to standard hyperbaric oxygen therapy of 90 minutes at 2 ATA, irrespective of the symptoms severity at presentation. CONCLUSIONS: Late recompression for DCS, 48 hours or more after surfacing, has clinical value and when applied can achieve complete recovery in 76% of the divers. It seems that the preferred hyperbaric treatment protocol should be based on US Navy Table 6.

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

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.

Hyperbaric oxygen induces late neuroplasticity in post stroke patients--randomized, prospective trial.

BACKGROUND: Recovery after stroke correlates with non-active (stunned) brain regions, which may persist for years. The current study aimed to evaluate whether increasing the level of dissolved oxygen by Hyperbaric Oxygen Therapy (HBOT) could activate neuroplasticity in patients with chronic neurologic deficiencies due to stroke. METHODS AND FINDINGS: A prospective, randomized, controlled trial including 74 patients (15 were excluded). All participants suffered a stroke 6-36 months prior to inclusion and had at least one motor dysfunction. After inclusion, patients were randomly assigned to "treated" or "cross" groups. Brain activity was assessed by SPECT imaging; neurologic functions were evaluated by NIHSS, ADL, and life quality. Patients in the treated group were evaluated twice: at baseline and after 40 HBOT sessions. Patients in the cross group were evaluated three times: at baseline, after a 2-month control period of no treatment, and after subsequent 2-months of 40 HBOT sessions. HBOT protocol: Two months of 40 sessions (5 days/week), 90 minutes each, 100% oxygen at 2 ATA. We found that the neurological functions and life quality of all patients in both groups were significantly improved following the HBOT sessions while no improvement was found during the control period of the patients in the cross group. Results of SPECT imaging were well correlated with clinical improvement. Elevated brain activity was detected mostly in regions of live cells (as confirmed by CT) with low activity (based on SPECT) - regions of noticeable discrepancy between anatomy and physiology. CONCLUSIONS: The results indicate that HBOT can lead to significant neurological improvements in post stroke patients even at chronic late stages. The observed clinical improvements imply that neuroplasticity can still be activated long after damage onset in regions where there is a brain SPECT/CT (anatomy/physiology) mismatch.

Effects of hyperbaric oxygen on blood glucose levels in patients with diabetes mellitus, stroke or traumatic brain injury and healthy volunteers: a prospective, crossover, controlled trial.

INTRODUCTION: A decrease in blood glucose levels (BGL) during hyperbaric oxygen treatment (HBOT) is a well-recognised phenomenon, but studies of this are limited and inconclusive. This study evaluated the effect of HBOT on BGL in patients with diabetes mellitus (DM), traumatic brain injury (TBI) or stroke and healthy volunteers in a prospective, open, controlled trial. METHODS: Thirty-nine participants were enrolled and evaluated twice: once during HBOT (90 minutes at 203 kPa), and once during a control session on normobaric air. Sessions were held up to two weeks apart and participants were instructed to eat the same diet. BGL was measured before, during and at the completion of each session. RESULTS: For the whole study group, there was a small but statistically significant decrease in BGL in both the HBOT (7.27 ± 3.66 mmol⁻¹ before to 6.71 ± 3.88 mmol ⁻¹ after, P = 0.037) and control (air) sessions (7.43 ± 3.49 mmol L⁻¹ before to 6.71 ± 3.77 mmol L⁻¹ after, P = 0.004). This fall did not differ between the two conditions (P = 0.59). Examining the three groups separately, BGL fell in all three subgroups, but this fall was only statistically significant for the air session in the diabetic group. There were no statistically significant differences in the BGL reduction when HBOT was compared to normobaric air in any of the three subgroups. CONCLUSIONS: BGL may decrease during HBOT and accordingly it should be monitored before entering the chamber. However, this decrease in BGL should probably not be attributed to the hyperbaric environment per se.

Isolated sternal fracture--a benign condition?

BACKGROUND: Fractures of the sternum may be associated with major injuries to thoracic organs, with serious consequences. OBJECTIVE: To assess the hospital course of patients diagnosed with isolated sternal fracture. METHODS: We reviewed 55 medical records of patients who were admitted with isolated sternal fracture to the emergency department during the period January 1990 through August 1999. RESULTS: Fifty-one patients were involved in motor vehicle accidents, and 4 sustained the injury as the result of a fall. Lateral chest X-ray upon admission was diagnostic in the majority of these patients (n = 53). Electrocardiography (n = 52) was abnormal in four patients--old myocardial infarction (n = 1), non-specific ST-T changes (n = 3). Cardiac enzymes (creatine-kinase-MB, n = 42) were pathologically elevated in five patients. Echocardiography, performed in patients with ECG abnormalities and/or elevated myocardial enzymes (n = 7), was normal in these patients as well as in another 18 patients. There were no intensive care unit admissions or arrhythmias during the hospital stay, which ranged from 6 hours to 6 days (mean 2.3 +/- 1.3 days, median 2 days). CONCLUSION: Our findings support the view that patients with isolated sternal fracture and no abnormality in ECG and cardiac enzymes during the early hours after injury are expected to have a benign course and can be discharged home from the emergency room within the first 24 hours.