Changes in cerebral oximetry during peritoneal insufflation for laparoscopic procedures

BACKGROUND: Changes in cardiac output may occur during insufflation for laparoscopic procedures. However, there are limited data regarding its potential effects on cerebral oxygenation.
MATERIALS AND METHODS: Cerebral oxygenation (ScO₂), end tidal CO₂, heart rate, blood pressure and oxygen saturation by pulse oximetry were recorded every 5 minutes prior to insufflation, during insufflation and after desufflation. Minute ventilation was increased to maintain normocapnia and the depth of anesthesia was adjusted or fluids/phenylephrine administered to maintain the blood pressure within 20% of the baseline.
RESULTS: The cohort for the study included 70 adults for laparoscopic herniorrhaphy, gastric bypass or cholecystectomy. A total of 1004 ScO₂ values were obtained during laparoscopy. The ScO₂ decreased from the baseline in 758 of the1004 data points. The ScO₂ was 0-9 less than the baseline in 47.8% of the values, 10-19 less than the baseline in 24.9% of the values and 20-29 less than the baseline in 26 values (2.6%). Eighty-two (8.2%) of the values were less than 80% of the baseline value, while 25 values (2.5%) were less than 75% of the baseline value. Twelve patients had at least one ScO₂ value that was less than 80% of the baseline and 6 had at least one ScO₂ value that was less than 75% of the baseline. Four patients of the cohort had ScO₂ values less than 80% of the baseline for more than 50% of the laparoscopic procedure.
CONCLUSIONS: Although relatively uncommon, significant changes in cerebral oxygenation do occur in some patients during insufflation for laparoscopic surgery.