Physiologic effects of simultaneous carbon dioxide insufflation by laparoscopy and colonoscopy: prospective...

The use of intraoperative carbon dioxide (CO(2)) colonoscopy during a laparoscopic colon operation is becoming more common. Simultaneous intracolonic and intraabdominal CO(2) insufflation may result in significant physiologic changes, but in-depth physiologic effects have not been studied to date. This study aimed to evaluate the physiologic changes and the overall safety of simultaneous CO(2) laparoscopy and colonoscopy.

A prospective pilot study was performed with 26 subjects (17 men and 9 women) undergoing laparoscopic surgical treatment for colorectal conditions adjunctively managed with CO(2) intraoperative colonoscopy. Surgery proceeded with CO(2) insufflation to a maximum pressure of 12 mmHg by laparoscopy and with a maximum CO(2) flow of 5 l/min via colonoscopy. Serial intra- and postoperative arterial blood gases, end-tidal CO(2), and minute ventilation were recorded during predetermined periods: during initial laparoscopy, during simultaneous colonoscopy and laparoscopy, during laparoscopy after colonoscopy, and after desufflation.

No significant morbidity resulted from simultaneous CO(2) insufflation. Three patients had a CO(2) partial pressure (PaCO(2)) greater than 50, and one patient with a body mass index (BMI) higher than 42 kg/m(2) had a PaCO(2) greater than 50 for more than 30 min and was compensated by increasing minute ventilation. The mean pH was 7.36 in the recovery room. Postoperatively, no patient had a pH lower than 7.3, prolonged intubation, or reintubation.

Simultaneous CO(2) colonoscopy and laparoscopy lead only to transient alterations in respiratory parameters that can be compensated. Based on these findings, simultaneous insufflation of CO(2) into the peritoneal cavity and the large bowel lumen during complex endoscopic procedures may be considered safe for most patients.