Myocardial hemodynamic and metabolic changes during abdominal insufflation with carbon dioxide

It is a well-known fact that laparoscopic procedures performed with carbon dioxide insufflation impair myocardial function. In this study, we aimed to determine the safety limitations of various intra-abdominal pressure values during abdominal insufflation with carbon dioxide. Of the 24 mongrel dogs, 6 were assigned to one of four different pressure groups (10, 15, 20 and 30 mm Hg), respectively. Cardiac output, right/left heart pressures, and the first derivative of ventricular pressure were monitored. Myocardial oxygen consumption, myocardial lactate/oxygen extraction, tissue lactate and adenosine triphosphate levels were determined. Measurements were performed initially as a control, at 15-min intervals during 1 h of insufflation and 1 h after desufflation. At 10 mm Hg carbon dioxide pressure, hemodynamic and metabolic parameters were not significantly different. Cardiac output decreased significantly in the 20 and 30 mm Hg groups (p < 0.05: 10, 15 vs. 20, 30 mm Hg). Although cardiac output did not change at 15 mm Hg, the dp/dt value was significantly reduced. Cardiac output at the 60th min was 1,960+/-75 ml/min in the 10 mm Hg group, 1,885+/-40 ml/min in the 15 mm Hg group, 1,770+/-45 ml/min in the 20 mm Hg group and 1,695+/-40 ml/min in the 30 mm Hg group. Myocardial oxygen consumption was reduced at 15, 20 and 30 mm Hg (p < 0.05: 10 vs. 15, 20 and 30 mm Hg). In the myocardial tissue, ATP decreased from 19+/-2 to 12+/-1.2 micromol/g at 15 mm Hg, from 19+/-1.9 to 9.4+/-1.3 micromol/g at 20 mm Hg and from 18+/-3.2 to 8.2+/-1.9 micromol/g at 30 mm Hg. Changes in hemodynamic and metabolic parameters of the heart are reversible and may not lead to any significant impairments in patients having normal cardiopulmonary function, but pose a risk in patients with respiratory disease and limited myocardial reserve.