Hemodynamiceffects of pneumoperitoneum and the influence of posture during anaesthesia forlaparoscopic surgery

The laparoscopic operating technique is being applied increasingly to a variety of intra‐abdominal operations. Intra–abdominal gas insufflation, i.e. pneumoperitoneum (PP), is then used to allow surgical access. The haemodynamic effects of PP in combination with different body positions have not been fully examined. Eleven patients without signs of cardiopulmonary disease were studied before and during laparoscopic cholecystectomy under propofol–fentanyl anaesthesia with controlled ventilation. Swan‐Ganz and radial arterial catheterization were used to determine haemodynamic data in the horizontal position, with a 15–20° head–down tilt and a 15–20° head–up tilt. The measurements were repeated after insufflation of carbon dioxide to an intraabdominal pressure of 11–13 mmHg, as well as during surgery. The ventricular filling pressures of the heart were strictly dependent on body position. PP in the horizontal position increased pulmonary capillary wedge pressure by 32% (P < 0.01), central venous pressure by 58% (P < 0.01), and mean arterial pressure by 39% (P < 0.01). When PP was combined with a head–down tilt, there was a further increase in filling pressures by approximately 40% (P < 0.01), while the reduction in filling pressures during the head–up tilt was counteracted by PP. During PP with a head–up tilt, the filling pressures did not differ from those in the horizontal position without PP. CI showed a certain dependency on filling pressures. It is concluded that PP causes signs of elevated preload and afterload. The combination of PP and a head–up tilt is associated only with signs of an elevated afterload. It is suggested that the haemodynamic response to PP, especially in combination with a head–down tilt, may be hazardous to patients with compromised heart function.