Effect of desiccation and temperature during laparoscopy on adhesion formation in mice.

OBJECTIVE To investigate the effects of desiccation (without cooling) and of oversaturation of the pneumoperitoneum on adhesion formation. DESIGN Prospective randomized trial. SETTING Academic research center. ANIMAL(S) BALB/c and NMRI female mice. INTERVENTION(S) The effect of desiccation using nonhumidified CO(2) on adhesion formation was evaluated in a laparoscopic mouse model. Body temperature (BT) was maintained at 37 degrees C using a homeothermic blanket. In addition to controls without desiccation, the effect of both hypothermia and desiccation on adhesion formation was evaluated. Subsequently the effect of oversaturating the pneumoperitoneum using a high energy gas to avoid any desiccation was studied. MAIN OUTCOME MEASURE(S) During surgery BT, pneumoperitoneum temperature, and relative humidity were monitored. Adhesions were scored after 7 days. RESULT(S) Adhesions increased with increasing levels of desiccation when BT was kept at 37 degrees C. This was prevented with humidified gas. If BT decreased, adhesions were fewer. Oversaturating the pneumoperitoneum increased adhesions due to high energy gas causing an increase in both BT and pneumoperitoneum temperature. CONCLUSION(S) Adhesions increase with desiccation and decrease when BT is reduced. Adhesions are minimized when humidified gas is used. Since desiccation is associated with cooling, its effect is generally underestimated because of the counterbalance with cooling. The concept of combining controlled intraperitoneal cooling with a rigorous prevention of desiccation might be important for clinical adhesion prevention.