HAEMODYNAMIC CHANGES IN PATIENTS UNDERGOING LAPAROSCOPIC CHOLESCYSTECTOMY: MEASUREMENT BY TRANSTHORACIC ELECTRICAL BIOIMPEDANCE

Abstract

SUMMARYUsing transthoracic electrical bioimpedance with the BoMed NCCOM3-R7, we measured cardiovascular changes in 16 ASA I and II Chinese patients undergoing laparoscopic cholecystectomy. The peritoneal cavity was insufflated with carbon dioxide to a pressure up to 15 mm Hg. Tidal volume, minute volume and end-tidal carbon dioxide partial pressure were kept constant. Insufflation resulted in a mean (so) 13 (14) % decrease in stroke index (SI) (P < 0.01), but the effect on cardiac index (Cl) was more variable (mean 7(17)% decrease, range 36% decrease to 22 % increase (P = 0.07)). Mean arterial pressure increased by 55 (29)% (P < 0.001) and systemic vascular resistance index increased by 63 (33) % (P < 0.001), with the maximum effect occurring 10–15 min after the commencement of insufflation. Multiple regression analysis showed a greater decrease in SI in patients with a small body mass index and large intraperitoneal pressure (P = 0.01), while a greater decrease in Cl was found in patients with a small body mass ndex and younger age (P = 0.001). Three patients had a further reduction in Cl during surgery, with one patient having a 48% decrease compared with pre- induction values. Deflation of the peritoneum resulted in an increase in both Cl (25 (26)%) and (22 (29)%) (P < 0.01) to values which were not different from pre-induction data. Arterial blood-gas analysis showed decreases in pH and base excess after 1 h of insufflation (P < 0.01). (Br. J. Anaesth. 1993; 70: 681–683)