Assessment of laparoscopic working space in guinea pigs (Cavia porcellus) undergoing carbon dioxide insufflation at different intra-abdominal pressures

Abstract

OBJECTIVE To evaluate pneumoperitoneal volumes (laparoscopic working space) in guinea pigs (Cavia porcellus) undergoing pneumoperitoneum via carbon dioxide insufflation at different intra-abdominal pressures (IAPs) (4, 6, and 8 mm Hg) and recumbencies (dorsal, right lateral, and left lateral). ANIMALS Six 3-to 4-month-old sexually intact female Hartley guinea pigs. PROCEDURES Guinea pigs were anesthetized, intubated, and had an abdominal insufflation catheter placed. A baseline abdominal CT scan was performed. Guinea pigs underwent insufflation, with each IAP given in a random order for 10 to 15 minutes with a washout period of 5 minutes between pressures. Abdominal CT scans were acquired at each IAP and at each recumbency. Pneumoperitoneal volumes were calculated using software. RESULTS Increases in IAP increased working space significantly (P