Safety of hyperbaric oxygen therapy in mechanically ventilated patients.

BACKGROUND: To evaluate the epidemiology of patients who require mechanical ventilation during hyperbaric oxygen therapy.
MATERIALS AND METHODS: One-hundred-fifty patients who required mechanical ventilation during hyperbaric oxygen therapy were prospectively studied during a 6-year period in a French university hyperbaric centre. We analysed the indication of hyperbaric oxygen therapy, agent used for sedation, presence of a chest tube, need for vasopressor agents and tolerance and appearance of side effects. Finally, we compared the outcomes of patients according to the presence or absence of acute respiratory distress syndrome (ARDS).
RESULTS: Eleven children and 139 adult patients were included (n = 150) in the study. In both populations, carbon monoxide poisoning (51%) and iatrogenic gas embolism (33%) were the two main causes of intubation and mechanical ventilation. The combination of midazolam and sufentanil was used in 85 (67%) patients. All of the patients were given a bolus of a neuromuscular blocker during the hyperbaric session, despite the presence of ARDS in 35 patients. Patient-ventilator asynchrony was the most frequent side effect in 6 (5%) patients and was often the consequence of suboptimal sedation. Mortality was higher in the group with ARDS (23%).
CONCLUSIONS: Carbon monoxide poisoning and iatrogenic gas embolism are the two main diseases of the patients who required mechanical ventilation during hyperbaric oxygen therapy in this study. Mechanical ventilation is a safe method for patients during hyperbaric oxygen therapy. Sedation needs to be perfected to avoid patient-ventilator asynchrony.