Impact of AirSeal ® insufflation system on respiratory and circulatory dynamics during laparoscopic abdominal surgery.

The effect of the AirSeal ® insufflation system on hemodynamic parameters, especially end-tidal carbon dioxide (EtCO 2 ), during laparoscopic abdominal surgery remains unclear. This retrospective single-center study included 333 consecutive patients who underwent laparoscopic hepatectomy (n = 43), gastrectomy (n = 69), colectomy (n = 137), or proctectomy (n = 84) using the AirSeal ® . Patient demographics and intraoperative hemodynamic parameters, such as EtCO 2 , peripheral capillary oxygen saturation (SpO 2 ), and arterial systolic blood pressure (ABP), were collected and analyzed. EtCO 2 was evaluated during the entire operative period (whole period) as well as the pneumoperitoneum period until specimen removal (pneumoperitoneum period). We defined "positive respiratory and circulatory responses" (positive responses) as a decrease in EtCO 2  ≥ 3 mmHg in addition to decreases in SpO 2  ≥ 3% and ABP ≥ 10 mmHg simultaneously, which suggest possible carbon dioxide (CO 2 ) embolism. The median EtCO 2 values of hepatectomy, gastrectomy, colectomy, and proctectomy in the whole period/pneumoperitoneum period were 37.3/37.4, 37.1/37.3, 37.4/37.9, and 38.2/38.4 mmHg, respectively. The EtCO 2 of proctectomy was significantly higher than that of gastrectomy during the whole and pneumoperitoneum periods (P < 0.05). In contrast, the EtCO 2 of hepatectomy was comparable to that of the other three surgeries in the whole and pneumoperitoneum periods. Meanwhile, nine (2.7%; eight hepatectomies and one proctectomy) patients showed positive responses, and one who underwent a partial hepatectomy developed a clinically manifested CO 2 embolism. Positive responses occurred during venous exposure or bleeding in all nine cases. Although the EtCO 2 of hepatectomy was comparable to that of the other surgeries using the AirSeal ® , laparoscopic hepatectomy showed a tendency of CO 2 embolism. Thus, a secure and careful surgical approach is mandatory for laparoscopic hepatectomy using the AirSeal ® insufflation system.