[Changes of static and dynamic characteristics of external respiration in divers after short-term dives down to 100 m].

In a series of short (up to 45 min without considering time of decompression) dives (SD) at depths down to 100 m under conditions of the Barentsev Sea five professional deep-sea divers were examined. In dives down to 40 m compressed air was used as breathing media, in dives to 60, 80 and 100 m--nitrogen-heliox mixture. Before the SD series the volume and velocity lung variables at rest and during forced expiration in air and heliox media were measured between separate SDs and on the 3rd day after the end of decompression with dive to 100 m, using computer spiro- and pneumotachometry methods. Bronchospastic syndrome, playing the leading role in the development of transient isolated or generalized airway obstruction, was shown to be evoked in divers during conduction of SD series. Obstructive phenomena are presumed to be connected with elastic properties' disturbance of lung tissue and development of expiratory collapse; they might cause continuous lung dilatation.