Changes in respiratory compliance at laparoscopy: measurements using side stream spirometry.

In order to quantify changes in total respiratory compliance (Crs) effected by peritoneal pressurization we measured, under standardized anaesthetic conditions and using side stream spirometry Crs in 32 patients scheduled for abdominal surgery through laparoscopic techniques. To qualify the changes in Crs as to the type (duration and patient's position) of surgery, 20 patients having cholecystectomy, eight having gastric fundoplication, and four having inguinal hernia repair were studied. At CO2 insufflation to a mean intraabdominal pressure of 11 cmH2O in the horizontal position, Crs decreased abruptly by 20% in each of the surgical sub-groups (P < 0.05-0.01). During the insufflation period a further deterioration was observed, most pronounced in inguinal hernia patients operated upon in a head-down tilt position (P < 0.05). In the cholecystectomy and fundoplication patients, operated upon in a head-up tilt, the recovery of Crs was immediate at deflation, whereas an incomplete recovery (P < 0.05 vs initial values) was seen in the hernia patients. In evaluating all patients none of the demographic factors, age, sex, body-mass-index, intraabdominal pressure, or duration of pressurization, were associated with the detected changes.