Alterations in the serological, pulmonary and cardiocirculatory parameters, potentially determined by CO2 pneumo-peritoneum during laparoscopic cholecystectomy, require careful intraoperative evaluation. With the aim of verifying the real entity of these alterations, an experience is reported relating to 76 of the 303 patients undergoing laparoscopic cholecystectomy during 14 months. During surgery, besides an obvious increase in pO2, a slight hypercarbia and a slight decrease in pH were observed, which required pharmacological intervention in only 5 cases. In no case did the respiratory and haemodynamic alterations observed necessitate the conversion into laparotomy. This initial experience gives us reason to conclude that careful monitoring of the respiratory parameters leads to an adequate anaesthesiological conduct, and thus facilitates the completion of laparoscopic procedures.