MYOCARDIAL HEMODYNAMIC AND METABOLIC CHANGES DURING ABDOMINAL INSUFFLATION WITH CARBON-DIOXIDE

It is a well-known fact that laparoscopic procedures performed with ca rbon dioxide insufflation impair myocardial function. In this study, w e 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 pressur e groups (10, 15, 20 and 30 mm Hg), respectively. Cardiac output, righ t/left heart pressures, and the first derivative of ventricular pressu re were monitored. Myocardial oxygen consumption, myocardial lactate/ oxygen extraction, tissue lactate and adenosine triphosphate levels we re 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 param eters were not significantly different. Cardiac output decreased signi ficantly 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 va lue was significantly reduced. Cardiac output at the 60th min was 1,96 0 +/- 75 ml/min in the 10 mm Hg group, 1,885 +/- 40 ml/min in the 15 m m 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 reduc ed at 15, 20 and 30 mm Hg (p < 0.05: 10 vs. 15,:20 and 30 mm Hg). In t he myocardial tissue, ATP decreased from 19 +/- 2 to 12 +/- 1.2 mu mol /g at 15 mm Hg, from 19 +/- 1.9 to 9.4 +/- 1.3 mu mol/g at 20 mm Hg an d from 18 +/- 3.2 to 8.2 +/- 1.9 mu mol/g at 30 mm Hg. Changes in hemo dynamic and metabolic parameters of the heart are reversible and may n ot lead to any significant impairments in patients having normal cardi opulmonary function, but pose a risk in patients with respiratory dise ase and limited myocardial reserve.