Comparison of head-down lithotomy position and Trendelenburg position on cardiac output in patients undergoing gynecological laparoscopic surgery

ObjectiveTo compare the changes in cardiac output (CO) and other hemodynamic parameters in patients undergoing gynecological laparoscopic surgery in head-down lithotomy position and Trendelenburg position. MethodsSixty patients were divided into head-down lithotomy group and Trendelenburg group.CO was recorded as baseline by a noninvasive cardiac output monitor NICOM® system after the placement of patients.These measurements were also acquired when the patients were placed in the 30° head-down tilt (T0) following pneumoperitoneum establishment.Stroke volume (SV), heart rate (HR) and CO were monitored at 1-minute intervals thereafter for a total of 10 minutes (T1-T10), and mean arterial pressure (MAP) and total peripheral resistance (TPR) were monitored every 5 minutes. ResultsThe reduction of CO in head-down lithotomy group was greater than that in Trendelenburg group (T0:-31%±19% vs. -9%±34%;T1:-32%±18% vs. -16%±38%;T2:-33%±19% vs. -16%±26%;T3:-32%±22% vs. -16%±28%;T4:-31%±18% vs. -12%±38%;T5:-30% ±17% vs. -14%±37%;T6:-31%±17% vs. -14%±33%, all P < 0.05) during the first 6 minutes. MAP at baseline in head-down lithotomy group was significantly higher than that in Trendelenburg group[(97±11) mmHg vs. (85±6) mmHg, P < 0.05].MAP decreased in head-down lithotomy group at T0 (-8%±16%) and increased in Trendelenburg group at T5 and T10 (T5:9%±15%, T10:12%±18%). ConclusionCO reduction was greater in patients in head-down lithotomy position than that in Trendelenburg position group during the first 10 minutes after adjusting the position following pneumoperitoneum establishment.