Dysbarism: A Jet Age Problem of All Physicians

¹ Surgeon General, U. S. Air Force
² Chairman, Department of Medicine, Wilford Hall U.S.A.F. Hospital

1. With increased utilization of commercial jet aircraft, the possibility of loss of cabin pressurization and subsequent high altitude exposure of the occupants increases. The adverse effects of exposure to the reduced barometric pressure of high altitude, per se, has not been publicized. Therefore, it becomes important for physicians to become familiar with the manifestations of altitude dysbarism.

2. The effects of reduced barometric pressure result from the gases trapped within the body cavities or the evolution of gases from the liquid phase within the tissues or body fluids.

3. In general, trapped gases can be quite discomforting, but not usually dangerous unless the pressures generated are sufficient to cause the rupture of a hollow viscus, and this is quite rare. Generally, re-establishment of a patent foramen between the cavity and the atmosphere will result in relief.

4. However, the problems that arise when the nitrogen in the body fluids or fat tissue comes out of solution can be life threatening. Since this is more apt to occur in older and more obese individuals, a significant percentage of the flying public can be considered "dysbarism prone." Here the manifestations are bends (with extremity pains), chokes (with the respiratory distress, substernal pain, and dry cough) and neurocirculatory collapse. Neurocirculatory collapse may present a bizarre pattern of neurologic aberrations which resolve if the patient recovers. When circulatory failure becomes evident, mortality can be expected to be high and intensive care is essential.

5. Since neurocirculatory failure has been reported to develop rapidly after a relatively symptom-free period, it is advocated that individuals who experience any manifestation of dysbarism be observed for at least two hours after removal from altitude exposure.

6. Generally treatment is supportive and includes the administration of oxygen. However, it appears that the early correction of reduced circulating plasma volume is also essential.