MAN UNDER PRESSURE.

Current achievements in environments at pressures higher than atmospheric are reviewed, ranging from the uses of hyperbaric oxygen for treatment to the concept of residence at high pressure for extended Continental Shelf exploration and very deep caisson work.A case is made for the use of high oxygen pressures in the treatment of hypoxias of acute onset, of certain infections, and as an adjunct to radiotherapy. Achievement of the desired high tissue tensions of oxygen while avoiding toxicity requires careful choice of both pressure and duration of exposure.Man has successfully dived to 1000 feet in the sea, and has remained for weeks at high pressures. Adequate prophylactic decompression remains a major problem, since current recompression procedures are to a large extent empirically derived. There are grounds for expecting improved prophylactic and therapeutic procedures when present studies are completed.