Prevention of suction-induced gastric mucosal damage in dogs.

Gastric suction has traditionally been available in three modes: continuous, sump, and intermittent. An intermittent air injection suction system (IAIS) has been developed in which small (20 to 30 mm) amounts of air are injected two to three times a minute. Very low (20 mm Hg) suction levels are applied. The hypothesis of the present study is that such a device will prevent suction-induced gastric mucosal damage, probably produced by suctioning of mucosa into the holes of the NG tube. IAIS should prevent this by physically expelling the mucosa out of the holes and allowing use of much lower suction levels. In 25 animals, gastric suction for 24 h in anesthetized dogs routinely produced ulcers. However, IAIS produced significantly fewer ulcers and in fewer animals. In 37 animals, the effectiveness of suction, measured by recovery of fluid instilled in the stomach, and the tendency of the tube to block were studied. Effectiveness was the same for all modes studied. Blockage was significantly less with IAIS.