Intra-operative tissue oxygen tension is increased by local insufflation of humidified-warm CO.sub.2 during open abdominal surgery in a rat model

Maintenance of high tissue oxygenation (PtO.sub.2) is recommended during surgery because PtO.sub.2 is highly predictive of surgical site infection and colonic anastomotic leakage. However, surgical site perfusion is often sub-optimal, creating an obstructive hurdle for traditional, systemically applied therapies to maintain or increase surgical site PtO.sub.2. This research tested the hypothesis that insufflation of humidified-warm CO.sub.2 into the abdominal cavity would increase sub-peritoneal PtO.sub.2 during open abdominal surgery. 15 Wistar rats underwent laparotomy under general anesthesia. Three sets of randomized cross-over experiments were conducted in which the abdominal cavity was subjected to alternating exposure to 1) humidified-warm CO.sub.2 & ambient air; 2) humidified-warm CO.sub.2 & dry-cold CO.sub.2 ; and 3) dry-cold CO.sub.2 & ambient air. Sub-peritoneal PtO.sub.2 and tissue temperature were measured with a polarographic oxygen probe. Upon insufflation of humidified-warm CO.sub.2, PtO.sub.2 increased by 29.8 mmHg (SD 13.3; p