The effect of pneumoperitoneum on haemodynamic parameters in morbidly obese patients.

Background: The type of anaesthetic used affects the cardiovascular function in morbidly obese patients during pneumoperitoneum. In this prospective randomized study, we evaluated the influence of inhalation anaesthesia with sevoflurane or intravenous anaesthesia with propofol on haemodynamic performance in obese patients during laparoscopy.

Methods: Patients scheduled for laparoscopic bariatric procedures were randomly divided into two groups: sevoflurane (group S) or propofol (group P). Haemodynamic function was measured using the transoesophageal Doppler method after induction of anaesthesia (T₁), insuflation of CO₂ (T₂) and in the anti-Trendelenburg position with pneumoperitoneum (T₃).

Results: One hundred patients were enrolled in the study. The demographic data did not differ between the groups. At T₂, the blood flow parameters and ventricle ejection parameters decreased in both groups whereas the systemic vascular resistance and mean arterial pressure increased. The heart rate was stable. At T₃, afterload parameters and heart rate increased in both groups yet blood flow parameters decreased in group P. The changes observed were not accompanied by any serious clinical signs of cardiovascular deterioration.

Conclusions: Pneumoperitoneum has an important negative impact on haemodynamic function in morbidly obese patients but those changes are not accompanied by severe cardiovascular disturbances. Volatile anaesthesia provides better haemodynamic stability during laparoscopic bariatric surgery in such patients.