[Effect of pneumoperitoneum on venous hemodynamics during laparoscopic cholecystectomy. Influence of patients' age and time of surgery].

Background And Objective: Abdominal hyperpressure developed during laparoscopic cholecystectomy by the effect of pneumoperitoneum represents an obstacle to the venous return that may facilitate thromboembolic complications. The aim of this study was to establish the effect of pneumoperitoneum in venous hemodynamics during laparoscopy.

Patients And Method: Prospective study of 31 consecutive patients who underwent laparoscopic cholecystectomy. Venous occlusion plethysmography was performed preoperatively, after anaesthetic induction, after insufflation, before pneumoperitoneum release and at the end of surgery. Changes of plethysmography were compared with preoperative values and according to age, obesity, presence of varicose veins and pneumoperitoneum time. Bilateral lower limb venous Duplex scanning was performed at days 1, 7 and 30 to detect deep venous thrombosis (DVT).

Results: Average age was 56 years, 66.6% females, 40% obese, 16% with varicose veins and the pneumoperitoneum time was < 45 min in 22.5% patients. Capacitance decreased progressively during surgery and was significantly reduced with pneumoperitoneum. The maximum venous outflow in the first second was reduced significantly at the end of pneumoperitoneum. These reductions were more evident in older patients.

Conclusions: Pneumoperitoneum produces plethysmographic changes on venous hemodynamics with a diminished venous return in lower limbs. Older patients have higher risk of thromboembolic complications, while obesity can also increase this risk. However, no DVT was demonstrated in this study.