[Technique of measuring esophageal pressure in rabbits and its application to measurement of pulmonary compliance and resistance].

Esophageal pressure (Pes) was measured under non-invasive condition by an esophageal balloon made by ourselves, and the optimal position of rabbits for measuring Pes was explored. The correspondence between Pes and pleural pressure (Ppl) was examined in rabbits during different depths of breathing with varied lengths of balloon and varied depths of insertion of balloon into the esophagus. The results showed that the amplitude of Pes only on supine position was higher than that on the left and right lateral and prone positions, but no significant difference was noticed among the 3 positions. The optimal balloon length was 4-6 cm. The optimal depth of insertion of balloon into the esophagus was 20 cm. The pulmonary dynamic compliance and pulmonary resistance were measured in 11 white rabbits with 5 cm balloon, 20 cm depth of insertion, on the left lateral position. The results were correspondent with other authors. No significant difference was noticed in repeated measurements on 8 of the 11 rabbits 5 days later.