Mixed venous versus central venous oxygen saturation in patients undergoing on pump beating coronary artery bypass grafting

To examine the validity of central venous oxygen saturation [ScvO 2] as a numerical substitution of mixed venous oxygen saturation [SvO 2] in adult patients undergoing normothermic on pump beating coronary artery bypass grafting [CABG]. Prospective clinical observational study was done at King Khalid University Hospital, King Saud University, Riyadh, Kingdom of Saudi Arabia. Thirty four adult patients scheduled for coronary artery surgery were included. Patients were monitored by a pulmonary artery catheter [PAC] as a part of our routine intraoperative monitoring. SvO 2 and ScvO 2 were simultaneously measured 15 minutes [T1] and 30 minutes [T2] after induction of anesthesia, 15 and 30 minutes after initiation of cardiopulmonary bypass [T3 and T4], and 15 and 30 minutes after admission to intensive care unit [T5 and T6]. ScvO 2 showed higher reading than SvO 2 all through our study. Our results showed perfect positive statistically significant correlation between SvO 2 and ScvO 2 at all data points. Individual mean of difference [MOD] between both the readings at study time showed MOD of 1.34 and 1.44 at T1 and T2 simultaneously. This MOD was statistically insignificant, but after on pump beating normothermic bypass was initiated; MOD was 5.2 and 4.4 at T3 and T4 with high statistical significance. In ICU, MOD continues to have high statistical significance, MOD was 6.3 at T5 and at T6 it was 4.6. In on pump beating CABG patients; ScvO 2 and SvO 2 are not interchangeable numerically. ScvO 2 is useful in the meaning of trend; our data suggest that ScvO 2 is equivalent to SvO 2, only in the course of clinical decisions as long as absolute values are not required

Effect of bispectral index [BIS] monitoring on postoperative recovery and sevoflurane consumption among morbidly obese patients undergoing laparoscopic gastric banding

Early and uneventful postoperative recovery of morbidly obese patients remains a challenge for anesthesiologists. It could be valuable to titrate the administration of inhaled anesthetic, such as sevoflurane, in morbid obese patients, in order to shorten emergence using bispectral index [BIS] monitoring. It would be a great advantage if BIS permitted a more rapid recovery and less consumption in morbidly obese patients with a high cost inhaled agent. The aim of the study is to show whether the titration of sevoflurane based on the BIS monitoring would allow shortening of recovery time in morbidly obese patients and to evaluate whether BIS monitoring would contribute to reduce the amount of sevofLurane administered while providing an adequate anesthesia. Thirty morbidly obese ASA I and II patients undergoing laparoscopic gastric banding [LAGB] procedures were studied. In the first group [15 patients], patients were anesthetized without the use of BIS [non BIS or control group], and sevoflurane being administered according to standard clinical practice [control group]. In the second group [15 patients], sevoflurane was titrated to maintain a BIS value between 40 and 60 during surgery, and then 60-70 during 15 min prior to the end of surgery [BIS group]. Recovery times were recorded. Time to extubation was also noted, as well as the time to achieve a modified Aldrete score of 9 were evaluated subsequently at 10-min intervals until 3 h after surgery by nurses who had no knowledge of the study. Sevoflurane consumption was calculated using the vaporizer weighing method. Awakening and extubation times were significantly shorter in the BIS group [P <0.05]. In the BIS [vs. non BIS] group, there were no significant differences observed in the time to obtain an Aldrete score of 9. The sevoflurane consumption and cost in the BIS group were lower than in the non BIS group [P <0.05]. Bispectral index monitoring during anesthesia for morbidly obese patients provides statistically significant reduction in recovery times. It also has the added advantage in decreasing sevoflurane consumption