Hemodynamic effects of pneumoperitoneum in lithotomy position

Aim of study: The study investigates the haemodynamic effects of the varying intraabdominal pressures and patient positions during gynecological procedures imploying pneumoperitoneum in lithotomy positions. Methodes: TEE was used to determine end-diastolic and end-systolic left ventricular surface areas and ejection fractions were calculated from these data. To evaluate intraabdominal volume shifts the diameter of the internal iliac vein was measured by mean of vaginal ultrasound. Results: In the horizontal lithotomy position both LVEDA and LVESA increased when intraabdominal pressure increased by 10 and 15 mmHg, respectively. LVAEF significantally decreased when intraabdominal pressure increased by 15 mmHg. Also DVII decreased. In Trendelenburg position there was no change in LVEDA, LVESA, LVAEF and DVII. In Anti-Trendelenburg position LVEDA and LVESA decreased. However, LVAEF remained constant and DVII increased. Conclusion: The increase of the intraabdominal pressure in the lithotomy position resultes in an increase in intrathoracic volume and an decrease in LVAEF via elevation of the the lower extremities and compression of the splanchnic vessels. There are no changes in Trendelenburg position. However, in Anti-Trendelenburg position, gravity results in a decrease in intrathoracic bloodvolume. In the deseased, dilatated heart the increase in intrathoracic volume may increase myocardial wail tension and hence oxygen demand, ultimately leading to an acute heart failure. As a result laparoscopic procedures in horizontal Lithotomy position shoud be avoided in patients with dilatative cardiomyopathy.