HELIUM AND CARBON-DIOXIDE PNEUMOPERITONEUM IN PATIENTS WITH PHEOCHROMOCYTOMA UNDERGOING LAPAROSCOPIC ADRENALECTOMY

Insufflation with helium is used to prevent respiratory acidosis, hype rcapnia, and cardiovascular instability associated with carbon dioxide (CO2) pneumoperitoneum. The aim of this prospective study was to comp are CO2 with helium pneumoperitoneum with special reference to respira tory and hemodynamic changes at different times during the operation. Altogether 22 pheochromocytoma patients undergoing laparoscopic adrena lectomy (LpA) were included using CO2 in 11 patients (CO(2)LpA) and he lium in 11 patients (HeLpA). The insufflation pressure was 12 mmHg. Th e two groups were comparable with regard to demographic data and preop erative management. CO2 and helium insufflation were associated with s imilar catecholamine increase. The most striking significant increase compared with the baseline was observed during tumor isolation: The me an plasma epinephrine (EPI) and norepinephrine (NE) levels increased 3 2.86-fold and 25.92-fold, respectively, in the CO(2)LpA patients and 2 7.43-fold and 18.46-fold, respectively, in the HeLpA patients. HeLpA d id not result in significant hypercarbia or acidosis at any measured i ntraoperative point; this was without any alteration in minute ventila tion to maintain these normal PaCO2, excess base (EB), and pH values. Significant increases of mean arterial pressure, pulmonary arterial pr essure, pulmonary vascular resistance index, PaCO2, EB, and acidosis w ere seen in the CO(2)LpA patients at the time of tumor isolation and t umor removal compared with those in HeLpA. patients. No patient requir ed conversion to open surgery. There were no significant differences b etween CO(2)LpA and HeLpA regarding mean operative time (117.50 +/- 93 .68 vs. 106.87 +/- 16.60 minutes), mean blood loss (168.54 +/- 78.63 v s. 142.02 +/- 109.26 mi), hospital stay (4 days), the need for analges ics, or mean time required to return to normal activity (12 days). The re was one wound infection in the HeLpA group and one wound hematoma a nd one case of atelectasis in the CO(2)LpA group. Helium may be the ag ent of choice for abdominal insufflation in patients undergoing LpA fo r pheochromocytoma, eliminating the adverse hemodynamic and respirator y changes associated with CO2 insufflation.