Oxygen and carbon dioxide tensions in the abdominal cavity and colonic wall of the rabbit

Abstract Chronically implanted Silastic tonometers were used to determine the oxygen and carbon dioxide tensions in the peritoneal cavity and colonic wall of the rabbit. The peritoneal cavity appeared to be particularly suitable for the tonometer technic since there is essentially no trauma around the tonometer due to implantation and the gas tensions are homogenous and show very little variation due to location. In the abdomen the mean PO 2 was 42 mm Hg, which is higher than that found in most tissues and also higher than venous PO 2 . In comparison with the intraperitoneal PO 2 , the PO 2 of the colonic wall was clearly lower during inhalation of both air and oxygen whereas the PCO 2 values in the colon and abdomen varied within the same limits.