Laparoscopic approach to pheochromocytoma: is a lower intraabdominal pressure helpful?

Laparoscopic adrenalectomy is gaining popularity because of its well-documented benefits. The aim of our study was to see if a decreased intraoperative intraabdominal pressure during laparoscopic adrenalectomy would affect the hemodynamic variables and the serum levels of catecholamines. We randomly divided 9 patients into 2 groups, maintaining either an intraabdominal pressure of 15 mm Hg (group A) or 8-10 mm Hg (group B). Norepinephrine and epinephrine blood levels were measured preoperatively, during endotracheal intubation, carboperitoneum, surgical manipulation of tumor just before the ligation of the adrenal vein, and tracheal extubation; the hemodynamic variables were recorded. The introduction of carboperitoneum resulted in an increase in heart rate and mean arterial blood pressure (MAP), although it was statistically insignificant. The norepinephrine levels showed a statistically significant increase in group A as compared with group B (P = 0.0002). Surgical manipulation of the tumor resulted in a significant increase in MAP and norepinephrine levels in group A (P = 0.007 and P = 0.0001, respectively). The epinephrine levels did not change as much because the tumor was probably predominantly norepinephrine-secreting. Norepinephrine levels continued to be high even during tracheal extubation in group A patients (P = 0.027). We conclude that a low intraabdominal pressure of 8-10 mm Hg causes less catecholamine release and fewer hemodynamic fluctuations.