End-tidal carbon dioxide and oxygen saturation compared with arterial blood gases during anaesthesia for laparoscopic oocyte recovery

ABSTRACT

Twenty- four patients undergoing laparoscopic oocyte were the subject of this study. The procedure was conducted under general anaesthesia with endotracheal tube and controlled ventilation. Anaesthesia was induced with thiopentone followed by atracurium and maintenance with 70% N2 O in oxygen and 1% isoflurane. During the laparoscopic procedure the end- tidal CO2 tension was continuously monitored with the CO2 monitor and the SaO2 was also continuously monitored by the pulse oxymeter. Arterial blood gases before and during CO2 pneumoperitonium insufflation and after CO2 deflation were compared and the arterial to end- tidal CO2 tension difference was evaluated during the laparoscopic procedure. Also the arterial SaO2 and SaO2 of the non-invasive pulse oxymeter were compared. The result of this study shows that there was no significant changes in the blood gas values among the three arterial samples with good oxygenation in all the samples. The mean arterial to end- tidal carbon dioxide tension difference was 1.8.4. 0.45 mm Hg. On the other hand during CO2 insufflation an increase of 1% in the SaO2 was observed in both the arterial and pulse oxymeter values. From this study we reach to a conclusion that in practice, end- tidal CO2 tension values can be used to monitor the PCO2 status during anaesthesia, being safe and reliable. On the other hand the pulse oxymeter SaO2 is a reliable guide for the state of oxygenation and with its use the need for arterial invasive techniques is very much minimized. Also we can conclude that general anaesthesia with endotracheal tube and controlled ventilation is a safe anaesthetic technique procedures needing prolonged CO2 insufflation like laparoscopic oocyte recovery