Complications and side effects of hyperbaric oxygen therapy.

BACKGROUND: Despite ongoing controversy, hyperbaric oxygen (HBO) therapy is frequently administered in various clinical situations. Probably because of the unique atmospheric conditions to which the patient is exposed, there are concerns about the safety aspects of this therapy. Possible complications during HBO therapy include barotraumatic lesions (middle ear, nasal sinuses, inner ear, lung, teeth), oxygen toxicity (central nervous system, lung), confinement anxiety, and ocular effects (myopia, cataract growth). METHODS: To analyze the medical safety of HBO therapy, this report reviewed complications and side effects of 782 patients treated for various indications with a total of 11,376 HBO therapy sessions within a multiplace chamber. The absolute treatment pressure was 240 or 250 kPa 114 or 15 msw). The compression was performed in a linear manner with 14 to 15 kPa (1.4 to 1.5 msw) x min(-1). All data were gathered prospectively within a special database. RESULTS: More than 17% of all patients experienced ear pain or discomfort as an expression of problems in equalizing the middle ear pressure. Most episodes were not related to a persistent eustachian tube dysfunction since they only occurred once. Barotraumatic lesions on visual otological examinations (ear microscopy) were verified in 3.8% of all patients. Patients with sensory deficits involving the ear region need special attention, because they seem to be at risk for rupture of the tympanic membrane (three cases documented). A barotrauma of the nasal sinuses occurred rarely and no barotraumatic lesions of the inner ear, lung, or teeth were noted. Oxygen toxicity of the CNS manifested by generalized seizures affected four patients without any recognizable risk factors or prodromes. None of the patients suffered recurrences or sequelae. Regular checks of the blood glucose in diabetics failed to reveal episodes of hypoglycemia as a cause for seizures. Lung function tests of patients undergoing prolonged treatment (average 52.8 sessions) did not deteriorate. CONCLUSION: Patients scheduled for HBO therapy need a careful pre-examination and monitoring. If safety guidelines are strictly followed, HBO therapy is a modality with an acceptable rate of complications. The predominant complication is represented by pressure equalization problems within the middle ear. Serious complications rarely occur.

The treatment of late radiation effects with hyperbaric oxygenation (HBO).

BACKGROUND: Late radiation injuries may impose a negative influence on the quality of life in the affected patients. In several entities, standardized treatment protocols are lacking. Hyperbaric oxygenation (HBO) has been shown to have beneficial effects in the treatment of late radiation sequelae. MATERIAL AND METHODS: The basic principles of HBO are reviewed as well as clinical issues. Current study protocols are presented. RESULTS: During HBO-therapy the patient breathes pure oxygen at pressures above 100 kPa. The oxygen solubility within the fluid phase of the blood is largely increased. Biological effects include an increased oxygen diffusibility, improved collagen synthesis and neoangiogenesis as well as an enhancement of antimicrobial defenses. By decreasing the capillary filtration pressure a reduction of edema becomes possible. HBO has been shown to prevent complications following surgery in irradiated tissues. Its efficacy as an adjunct in the treatment of osteonecroses in radiation patients could be demonstrated. In addition, the loss of osseointegrated implants in the maxillofacial bones of these patients could be significantly reduced. Further indications include soft tissue necroses, hemorrhagic cystitis and proctitis in tumor patients that have been treated by radiotherapy as part of a multimodality approach. CONCLUSIONS: HBO in the treatment of late radiation effects is still subject of investigation, but remarkable results have been reported. Optimized treatment protocols need to be determined in various entities. The rate of side effects is acceptable low.

[Dehydration--a risk factor for the decompression-accident in diving]. / Dehydrierung als Risikofaktor fur den Dekompressionsunfall beim Sporttauchen--ein Fallbericht.

We report on a decompression-accident with neurological manifestation in an experienced recreational diver. As no obvious omission against the prescribed rules of decompression could be observed, dehydration due to intense jogging prior to the dive was identified as a risk-factor. Hyperbaric treatment resulted in a complete restitution. The physiological aspects are discussed and recommendations for the fluid-intake before diving are given.