Assessment of splanchnic tissue oxygenation by gastric tonometry in patients undergoing laparoscopic and open cholecystectomy

This experimental study compared the effects of laparoscopic (n=31) and open (n=32) cholecystectomy on gastric intramucosal pH (pH(i)), For this purpose, pH(i) was measured tonometrically before induction of anaesthesia, at 30-min intervals during surgery, and 1, 2 and 4 h after operation in otherwise healthy patients undergoing elective cholecystectomy. Additionally, perioperative arterial pH (pH(a)), arterial carbon dioxide tension (P-aco2), intramucosal carbon dioxide tension, arterial bicarbonate concentration, end-tidal carbon dioxide pressure (P-Eco2), levels of serum lactate, lactate dehydrogenase (LDH) and gamma-glutamyl transferase (GGT), haematocrit and arterial blood pressure were recorded. In the two groups no significantly different changes occurred in pH(i), pH(a), serum lactate concentration or haematocrit at any of the observation times. P-Eco2 and P-aco2 were significantly raised during the laparoscopic procedure, whereas levels of LDH and GGT and arterial blood pressure rose during and after open cholecystectomy. In spite of the increased intra-abdominal pressure and the peritoneal carbon dioxide absorption related to the creation of a pneumoperitoneum, no decrease in pH(i) was detectable during laparoscopic cholecystectomy.