Does increasing end-tidal carbon dioxide during laparoscopic cholecystectomy matter?

To examine the adverse effects of peritoneal carbon dioxide (CO₂) insufflation during laparoscopic cholecystectomy, both hemodynamic and respiratory alterations were continously monitored in 17 adult patients using noninvasive Doppler ultrasonography and a continuous spirometric monitoring device. During the surgery, which was performed under inhalational general anesthesia, intraabdominal pressure was maintained automatically at 10mmHg by a CO₂ insufflator, and a constant minute ventilation, initially set to 30-33 mmHg of end-tidal CO₂ (ETCO₂), was maintained. Despite considerable depth of anesthesia, peritoneal CO₂ insufflation induced a significant and immediate increase of mean blood pressure (+42%) and systemic vascular resistance (+62%), accompanied by a slight depression of cardiac index (-12%, nonsignificant), while the ETCO₂ gradually increased and maximized around 30min following the initial CO₂ insufflation. The stress of 10mmHg pneumoperitoneum was a major cause of hemodynamic changes during laparoscopic cholecystectomy. Some clinical strategies such as deliberate intraabdominal insufflation at the initial phase might be required to minimize these hemodynamic changes.