When the effects are seen in the lungs it is called the “Lorrain Smith” effect. Pulmonary toxicity may occur at partial pressures of O2 of 2 to 3 bar (200-300KPA) or 100 % O2 at 2-3 times atmospheric pressure. Symptoms may begin after exposures of three hours.
Patients should understand and recognize the signs of pulmonary toxicity. These include chest tightness; dry, hacking cough; and difficulty getting a full breath. The use of air breaks should be discussed with the patient and instruction in the use of a mask, hood, tent, etc. should be gone over.
Pneumothorax in a monoplace chamber is very serious. In the multiplace chamber pneumothorax may be reduced in the usual way by inserting a chest tube. In the monoplace chamber the emergency decompression protocol needs to be followed and the chest tube is inserted at surface.