The safety of hyperbaric oxygen treatment--retrospective analysis in 2,334 patients.

INTRODUCTION: Hyperbaric oxygen (HBO2) therapy is applied in a growing number of cases for patients with different comorbidities and is considered a generally safe therapy. The main side effects related to HBO2 therapy are barotrauma, central nervous system- and pulmonary oxygen toxicity, claustrophobia, anxiety and visual disturbances. The aim of this study was to evaluate the incidence of side effects associated with HBO2 therapy and risk factors in a large cohort of patients treated for different indications. METHODS: We conducted a retrospective analysis of 2,334 patients treated in the Sagol Center of Hyperbaric Medicine and Research, Assaf Harofeh, Israel, between June 2010 and December 2014. Patients were classified to one of three categories of indications: Category A--non-neurological indications; Category B--neurotherapeutic indications; and Category C--acute indications. RESULTS: From a total of 2,334 patients, 406 (17.4%) experienced adverse event(s) (one or more) during HBO2 therapy sessions. The overall per-session incidence was 721:100,000 events:sessions (0.72%). The main complication was middle ear barotrauma, which occurred in 9.2% of patients and in 0.04% of sessions. Females and children under the age of 16 years had increased risk for barotrauma. Other complications--hypoglycemia, oxygen toxicity, dizziness, anxiety reactions, dyspnea and chest pain--occurred in 0.5-1.5% of patients. CONCLUSIONS: Strict operational protocols, including pre-HBO2 therapy evaluations and in-chamber monitoring, are essential and improve patient safety. When applied, HBO2 therapy can be considered one of the safest medical treatments available today.

Seizures during hyperbaric oxygen therapy: retrospective analysis of 62,614 treatment sessions.

INTRODUCTION: Hyperbaric oxygen (HBO2) therapy is considered to be a generally safe therapy. However, data regarding seizure incidence during HBO2 therapy as a clinical presentation of central nervous system- (CNS) related oxygen toxicity are conflicting (ranging from 1:10,000 to 1:600 seizures:hyperbaric sessions). The risk for seizures is of significant importance for the growing population of patients suffering from chronic neurological disorders such as traumatic brain injury and stroke who are treated with HBO2. The aim of this study was to evaluate the incidence of seizures during HBO2 therapy in a large cohort of patients and determine whether patients with known chronic neurological disorders are at increased risk. METHODS: Retrospective analysis of 2,334 patients treated at the Sagol Center of Hyperbaric Medicine and Research, Assaf Harofeh Medical Center, Israel, between June 2010 and December 2014. Patients were grouped into one of three categories according to indication for HBO2 therapy: Category A--non- neurological indications; Category B--neurological indications; and Category C--acute indications. RESULTS: A total of 62,614 hyperbaric sessions, administered to 2,334 patients, were included in the analysis. The overall incidence of seizures during hyperbaric sessions was 0.011% (1:8,945), occurring in seven (0.3%) patients. Only one patient had a clear oxygen toxicity-induced seizure, with an overall incidence of 1:62,614. CONCLUSIONS: Seizures induced by oxygen toxicity during HBO2 therapy are extremely rare. Moreover, in relation to oxygen-induced seizures, HBO2therapy can be considered safe for patients suffering with chronic neurological disorders except for uncontrolled epilepsy.

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

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.

Hyperbaric oxygen, oxidative stress, NO bioavailability and ulcer oxygenation in diabetic patients.

BACKGROUND: Hyperbaric oxygen therapy (HBO2) increases tissue oxygenation, thus serving as an adjunct therapy for diabetic wounds. However, in some patients there is insufficient increase in tissue O2. AIMS: To investigate the pathophysiology of insufficient HBO2 and the possible role of N-acetylcysteine (NAC). METHODS: Prospective, randomized, cross-over trial included 50 diabetic patients with non-healing ulcers. Each patient received two treatments with 100% oxygen/2ATA. NAC was administered i.v. at one of the two treatments. Basal and post-treatment peri-wound transcutaneous O2 (TcPO2) pressure, malondialdehyde (MDA), total anti-oxidant status (TAOS) and nitric oxide (NO) were assessed. An ulcer oxygenation increase above 200 mmHg was accepted as sufficient. RESULTS: During HBO2, 17 patients (34%) demonstrated insufficient increase in TcPO2. Concomitantly, their TAOS and NO decreased, while MDA increased. NAC administration attenuated these parameters, thus improving the HBO2 outcome. In those affected by NAC, the cure rate was 75%. By contrast, in 66% of patients with sufficient increase in TcPO2 TAOS was increased and MDA decreased irrespective of NAC administration. The cure rate in this subgroup was 82%. CONCLUSIONS: Insufficient increase of ulcer oxygenation during HBO2 results from exaggerated oxidative stress and decreased NO bioavailability. NAC administration-induced modulation of both parameters and may improve ulcer oxygenation during HBO2.

Improved quality of life with hyperbaric oxygen therapy in patients with persistent pelvic radiation-induced toxicity.

AIMS: We report the results of hyperbaric oxygen therapy (HBOT) used in the treatment of radiation-induced persistent side-effects after the irradiation of pelvic tumours. MATERIALS AND METHODS: Between January 2001 and December 2005, 13 women (median age 60.3 years) with radiation combined proctitis/cystitis (n=6), longstanding vaginal ulcers and fistulas (n=5) and longstanding skin injuries (n=2) underwent HBOT in a multiplace chamber for a median of 27 sessions (range 16-40). The treatment schedule was HBOT 100% oxygen, at 2 absolute atmospheres, for 90 min, once a day. For radiation-induced toxicity grading we used the National Cancer Institute Common Toxicity Criteria (CTC) grading system, before and after HBOT. RESULTS: Thirteen patients underwent an adequate number of HBOT sessions. The mean CTC grading score before HBOT was 3.3+/-0.75, whereas the mean CTC grading score after HBOT was 0.3+/-0.63. The scores showed a significant improvement after HBOT (P=0.001; exact Wilcoxon signed-rank test). Rectal bleeding ceased in five of six patients with proctitis and dysuria resolved in six of seven cystitis patients. Macroscopic haematuria stopped in seven of seven patients. Scar complications resolved in two of two patients. None reported HBOT-associated side-effects. CONCLUSION: HBOT is apparently safe and effective in managing radiation-induced late side-effects, such as soft tissue necrosis (skin and vagina), cystitis, proctitis and fistulas.

Hyperbaric oxygen therapy for nonhealing vasculitic ulcers.

BACKGROUND: Cutaneous nonhealing ulceration is a threatening manifestation of vasculitis. Hyperbaric oxygen (HBO), frequently used as adjuvant therapy for patients with ischaemic ulcers, exerts additional beneficial effects on the vascular inflammatory response. AIM: To evaluate the effect of HBO on vasculitis-induced nonhealing skin ulcers. METHODS: The study population comprised 35 patients aged >or= 18 years with severe, nonhealing, vasculitis-induced ulcers that had not improved following immunosuppressive therapy. Baseline ulcer tissue oxygenation was evaluated at room air concentration (21% O2), at 1 atmosphere absolute (ATA) breathing 100% O2, and at 2 ATA breathing 100% O2. The baseline treatment protocol consisted of a 4-week course of 100% O2 for 90 min at 2 ATA, five times/week. RESULTS: The mean baseline ulcer tissue oxygenation (3.1 +/- 2.4 kPa at room air concentration), was significantly increased to 13.9 +/- 11.9 kPa at 1 ATA breathing 100% O2 (P < 0.001), and subsequently increased further to 59.1 +/- 29.8 kPa at 2 ATA breathing 100% O2 (P < 0.001). At the end of the hyperbaric therapy, 28 patients (80%) demonstrated complete healing, 4 (11.4%) had partial healing and 3 (8.6%) had no improvement. None of the patients had any side-effects related to the HBO therapy. CONCLUSION: HBO therapy may serve as an effective safe treatment for patients with vasculitis having nonhealing skin ulcers. Further studies are needed to evaluate its role as primary therapy for this group of patients.