MEASUREMENT OF OXYGEN CONCENTRATION IN DELIVERY SYSTEMS USED FOR HYPERBARIC-OXYGEN THERAPY

Efficient delivery of oxygen is important during hyperbaric oxygen the rapy. We compared two systems in common use, and developed a method to ensure that O-2 delivery was adequate during treatment. The systems w ere a demand valve system with an oral-nasal mask, and a continuously ventilated hood. Five groups were studied over two different time peri ods, and a further trial was undertaken to examine exhaled O-2 levels. The results showed that an acceptable Fi(O2) could be reliably achiev ed only with the continuously ventilated hood system or when trained s taff supervised their colleagues using the demand system. Inasmuch as the oral-nasal mask system is the standard equipment for the North Sea diving industry, this work shows the importance of ensuring that the correct dose of O-2 is delivered. The study indicates, however, that i dentification of the problem does not always allow a complete solution , and that a head-based system is more reliable.