[Influence of pneumoperitoneum on respiratory function during urological laparoscopic surgery]

To determine the influence of pneumoperitoneum on respiratory function during urological laparoscopic surgery.

We performed laparoscopic surgery on 82 patients, 45 of these patients were examined in detail of the effect of pneumoperitoneum on the respiratory function. Of these 45 patients, 14 patients received lymphadenectomy and 31 patients received adrenalectomy. For comparative analysis, 4 patients with laparoscopic cholecystectomies were also examined. Under general anesthesia, carbon dioxide tension (PaCO2) was analyzed before, during, and after the pneumoperitoneum. The data were analysed along with 4 factors; the patient's spirographic parameters, alveolar-arterial gas difference (AaDO2), insufflation pressure for the pneumoperitoneum, and operating time.

After starting the pneumoperitoneum, PaCO2 levels rose significantly. The PaCO2 levels of patients underwent laparoscopic adrenalectomy were higher than that of patients underwent laparoscopic cholecystectomy. The preoperative vital capacity and forced expiratory volume in one second (FEV1.0) did not show a significant difference of increase in the degree of PaCO2 increase. In contrast, the important factors that were closely related to the elevation of PaCO2 were preoperative AaDO2 and intraoperative insufflation pressure. Patients with high preoperative AaDO2 (> 10 torr) showed a significant increase in PaCO2 levels after pneumoperitoneum. When insufflation pressure was high (> = 10 mmHg), there was a significant rise of PaCO2 after pneumoperitoneum. In all patients whose operating time was 300 minutes or more, high levels of PaCO2 continued on the next day after surgery.

We should still carefully observe the insufflation pressure, operating time, and other ventilation conditions during laparoscopic surgery.