Intra-operative risk and haemodynamic etfects of the CO₂-pneumoperitoneum in laparoscopic surgery

Abstract

The benetits of minimally invasive surgery led to an increasing rate of laparoscopic procedures in older patients. These patients profit most from the p.op. advantages of laparoscopic surgery. On the other hand they often display cardiovascular risks with the intra-operative risk of the CO₂-pneumoperitoneum still under discussion. Methods: The haemodynamic etfects of CO₂-pneumoperitoneum were investigated. Monitoring included cardiac output (CO), central venous pressure (CVP), pulmonary arterial pressure (PAP) and wedge pressure (PAWP), femoral venous pressure (FVP), intra-oesophageal pressure (IEP), systemic vascular resistance (SVR) and transmural right-atrial pressure (TMP), and was performed in a controlled, experimental model. Results: Establishing the pneumoperitoneum caused initially a 35% decrease in CO. SVR, as an indicator of cardiac afterload, increased clearly. The increased intra-abdominal pressure led to a reduction of venous retlux from the periphery and squeezed the venous reservoir within the abdominal cavity. Cardiac preload was altered, too. The elevated cardiac afterload adapted under pneumoperitoneum. After desufflation cardiac output rose far above normal. Conclusions: These results indicate a strong cardiac stress after insufflation and desufflation. This is caused by the increased intra-abdominal pressure rather than by systemic etfects of resorbed CO₂. Laparoscopic procedures in patients with clinical signs of cardiovascular insufficiency should only be performed with substantial intra-operative monitoring. Otherwise low pressure pneumoperitoneum and/or pressure and gasless laparoscopy could be considered.

Key Words:

• laparoscopic surgery
• CO₂-pneumoperitoneum
• pathophysiology
• intra-operative risk