The Effects of Hyperbaric-Oxygen Tensions on Pulmonary Surfactant in Guinea Pigs and Rats

Abstract

One of the major problems in the use of hyperbaric oxygen is its effect on the pulmonary parenchyma itself (Lorrain Smith effect), consisting of extensive congestion, edema, inflammatory infiltration of the alveoli and interstitial tissues, and progressive focal atelectasis.1The purpose of this work was to investigate the effects of high oxygen tensions on the alveolar-lining-layer surfactant, since alteration of this could account in part for the observed changes. Methods Adult guinea pigs or albino rats were placed in a hyperbaric chamber constructed from a pressure cooker with addition of an oxygen inlet and a pressure gauge. Adequate soda lime was added to remove any carbon dioxide that might accumulate during a ten-hour period. After the animals were inserted, the chamber was flushed with oxygen to remove all room air. The pressure was gradually increased to 45 pounds per square inch (psi) and maintained for the duration of the