PERITONEAL VENTILATION IN RABBITS - AUGMENTATION OF GAS-EXCHANGE WITHCISAPRIDE

Background - Peritoneal ventilation has been shown to be effective in achieving extrapulmonary oxygenation and carbon dioxide elimination in an animal model of severe adult respiratory distress syndrome (ARDS). Cisapride is a ''prokinetic'' agent (increases gastric emptying), tha t may increase the splanchnic circulation and thus favourably affect g as exchange in peritoneal ventilation. Methods - Using Doppler ultraso und the effect of cisapride on the portal venous circulation was exami ned in eight spontaneously breathing rabbits and the effect of cisapri de on gas exchange in five rabbits spontaneously breathing room air wa s compared with that of a control group who did not receive cisapride. Its effect on gas exchange in five rabbits with ARDS being treated wi th mechanical lung and peritoneal ventilation was compared with that o f a control group, and its effect on gas exchange in five rabbits with ARDS treated with conventional ventilation was also compared with tha t of a control group. Results - Enteral administration of cisapride in creased portal venous blood velocity, as measured ultrasonographically , by a mean of 188% one hour after receiving the drug. In rabbits with ARDS being treated with both peritoneal ventilation and mechanical ve ntilation to the lungs, those receiving cisapride had arterial oxygen tensions 1.5-3 times that of controls. Cisapride had no effect on arte rial blood gas tensions in rabbits who were spontaneously breathing ro om air, nor in rabbits with ARDS who received only conventional mechan ical lung ventilation. Conclusions - Cisapride increases arterial oxyg enation in rabbits with severe ARDS treated with peritoneal ventilatio n, probably due to its ability to increase splanchnic circulation. It should be considered as an adjuvant medication to peritoneal ventilati on.