Gastric tonometry accurately predicts mortality in experimental peritonitis in both laparoscopic and conventional surgery

Objectives: Tonometry is widely used in the diagnosis of sepsis and splanch nic ischemia. This study was devised to analyze the predictive value of gas tric tonometry for outcome of experimental viscus perforation-induced perit onitis. The impact of conventional and laparoscopic intervention on tonomet ric measurements was the main scope. Methods: This randomized controlled in tervention trial was performed in a University experimental laboratory, usi ng 24 female Duroc pigs. Pigs were subjected to gastric perforation followe d by a 12 h interval of peritonitis, and then to either laparoscopic or con ventional surgical repair of the defect with peritoneal lavage. Gastric ton ometry and cardiocirculatory monitoring were performed. Results: Septic sho ck associated with peritonitis and subsequent lethal outcome was accurately predicted with gastric tonometry. Changes of gastric mucosal pH correlated significantly with decreases of MAP ( r(2) = 0.880; P < 0.001) and SVR (r( 2)=0.678; P<0.001), increase of QT (r(2) = 0.486; P = 0.013), and mortality (r = 0.752; P < 0.001). Mortality was significantly higher in laparoscopic ally treated animals compared to those subjected to the open procedure (78% vs 22%, P < 0.045). Conclusions: Gastric tonometry accurately predicted mo rtality in experimental peritonitis. The decline of gastric mucosal pH in t he laparoscopic group was more than double that of to conventionally treate d animals. This finding not only reflected the increase of systemic CO2 due to higher absorption during CO2-pneumoperitoneum, but probably also indica ted a more severe form of splanchnic ischemia during laparoscopic surgery E ven through tonometry can be used to accurately predict mortality and separ ate the high risk group, extreme caution should be applied under conditions associated with severe peritonitis.