Laparoscopy and tribology: The effect of laparoscopic gas on peritoneal fluid

Study Objective. To assess the changes in viscosity of peritoneal fluid during laparoscopic exposure to CO2 insufflation. Design. Analysis and mathematic modeling of peritoneal fluid viscosity in vivo and in vitro as a result of exposure to unconditioned CO2 (Canadian Task Force classification II-2). Setting. Medical school university research laboratory and hospital. Materials. Peritoneal fluid from 45 women. Intervention. Peritoneal fluid was obtained at laparoscopy before insufflation and tested for viscosity after exposure to currently used raw dry unconditioned CO2. Measurements and Main Results. Peritoneal fluid viscosity was tested by viscometric methods and mathematic modeling. Initial viscosity of peritoneal fluid before gas exposure was 1.425 centipoise (cP). Viscosity measurements were obtained at 20-second intervals for gas flows of 1 and 3 L/minute. Increases in viscosity occur rapidly, and by 200 seconds it was 59 cP and 98 cP for 1 and 3 L. flow rates, respectively. Conclusion. Very dry CO2 for laparoscopy causes peritoneal fluid viscosity to increase dramatically.