Bispectral index monitoring during isoflurane and sevoflurane anesthesia

The bispectral [BIS] index has previously been shown to be a quantifiable measure of the sedative and hypnotic effects of anesthetic drugs. This study was designed to test the hypothesis that the BIS monitoring would facilitate recovery from volatile anesthetics compared with standard clinical monitoring practices after ambulatory surgery. Eighty consenting patients undergoing laparoscopic cholecystectomies were randomly assigned to one of four treatment groups. After a standardized induction, anesthesia was maintained with isoflurane in combination with nitrous oxide, 65% and fentanyl 1.5 micro g/kg [Groups I and II]. Patients in Group III and IV, received sevoflurane in combination with nitrous oxide, 65% and fentanyl 1.5 micro g/kg. In the control groups [Group I and III], the anesthesiologists were blinded to the BIS value, and the volatile anesthetics were administered according to standard clinical practice to maintain vital signs within 20% of preoperative values. In Groups II and IV, the volatile anesthetics were titrated to maintain the BIS value of 50-60. Hemodynamic variables, the end-tidal isoflurane and sevoflurane concentrations and BIS values were recorded at 5-min intervals during the maintenance period. The volatile anesthetic usage and the times from discontinuation of anesthesia to verbal response, extubation, spontaneous eye opening, and orientation, PACU stay and time to tolerate fluid intake and home-readiness were recorded. During the operation, the BIS index values [mean +/- SD] were significantly lower in the control groups compared with the BIS-titrated groups [42 +/- 8 and 44 +/- 6 in Groups I and III vs. 55 +/- 4 and 57 +/- 5 in Groups II and IV, respectively]. During the maintenance period, the end-tidal concentrations of isoflurane and sevoflurane were significantly lower [P < 0.001] in the two BIS-titrated groups compared with the control groups [1 +/- 0.2% vs. 0.6 +/- 0.1% in Groups I and II and 1.5 +/- 0.3% vs. 1 +/- 0.2% in Groups III and IV, respectively. Compared with the control groups, the volatile anesthetic requirements [MAC-h] and the usage [ml] of isoflurane and sevoflurane were significantly lower in their respective BIS-titrated groups. The volatile anesthetic usage in the BIS-titrated groups was 38 and 33% lower [P < 0.05] compared with the control groups in patients receiving isoflurane and sevoflurane respectively. Times to verbal responsiveness, extubation, spontaneous eye opening, orientation, PACU stay and time to tolerate fluid intake were significantly shorter in the BIS-titrated groups compared with the control groups [P < 0.05]. However, there was no significant difference in times to achieve home readiness between BIS monitored groups and control groups. Titrating isoflurane or sevoflurane using the BIS monitor decreased their consumption and contributed to a faster emergence and recovery from anesthesia in outpatients undergoing laparoscopic cholecystectomies

Analgesic efficacy of intraperitoneal ropivacaine or combined with intravenous paracetamol for laparoscopic cholecystectomy

Intraperitoneal instillation of ropivacaine 0.25% immediately before and after surgery and intravenous [IV] administration of paracetamol at the end of surgery may reduce postoperative pain after laparoscopic cholecystectomy. The aim of the study was to examine whether intraperitoneal instillation of ropivacaine with or without IV paracetamol improves postoperative pain after laparoscopic cholecystectomy. After standardized general anesthetic, total of 60 patients were randomly assigned to one of three groups, 20 patients each. Group 1 received intraperitoneal instillation of 20 ml 0.9% saline before and after surgery and IV 100 ml 0.9% saline at the end of surgery [Placebo group]. Group 2 received intraperitoneal instillation of 20 ml ropivacaine 0.25% before and after surgery [total 100 mg ropivacaine] and IV 100 ml 0.9% saline at the end of surgery [Ropi group]. Group 3 received intraperitoneal instillation of 20 ml ropivacaine 0.25% before and after surgery and IV paracetamol 1 gm [in 100 ml bottle] at the end of surgery [Ropi-Para group]. Postoperative pain was rated at 0, 3, 6, 12, and 24 h postoperatively by visual analogue scale scores [VAS]. Total rescue analgesic consumption of morphine during the first 24 h after surgery and time until first analgesic request were recorded. Patients in Placebo group experienced visceral pain mainly and to a lesser extent incisional pain during the first 24 h after surgery. Patients in Ropi group experienced significantly less visceral pain than patients in Placebo group at 3 h after surgery [p < 0.05]. However, there was no significant difference in the intensity of the incisional pain between Ropi and Placebo group at any time after surgery. Patients in Ropi-Para group experienced significantly less visceral and incisional pain than patients in Placebo group at 3 and 6 h after surgery. Patients in Ropi-Para group experienced significantly less incisional pain than patients in Ropi group at 3 and 6 h after surgery. Also, patients in Ropi-Para group experienced significantly less visceral pain than patients in Ropi group at 6 h after surgery. Rescue morphine consumption was significantly less in Ropi-Para group [13 +/- 3 mg] compared to Placebo group [37 +/- 9 mg] [p < 0.001] and Ropi group [21 +/- 5 mg] [p < 0.05]. Also, rescue morphine consumption was significantly less in Ropi group compared to Placebo group [p < 0.05]. Time to first request for analgesia was significantly longer in Ropi-Para group [369 +/- 81 min] compared to Placebo group [35 +/- 29 min] [p < 0.01] and Ropi group [192 +/- 65 min] [p < 0.05]. Also, time to first request for analgesia was significantly longer in Ropi group compared to Placebo group [p<0.05] Intraperitoneal instillation of 20 ml ropivacaine 0.25% before and after surgery [total 100 mg ropivacaine] in addition to IV administration of paracetamol at the end of surgery provides better analgesia after laparoscopic cholecystectomy than that produced by intraperitoneal instillation of ropivacaine alone

Intra-articular magnesium sulphate versus bupivacaine for postoperative analgesia in outpatient arthroscopic knee surgery

Several medications are commonly injected intra-articularly for postoperative analgesia after arthroscopic knee surgery. Among the potentially efficient substances, magnesium could be of particular interest through its NMDA-receptor blocking properties. We designed this study to determine whether intra-articular [IA] magnesium sulphate [MgSO4] results in better analgesia and whether its combination with bupivacaine would provide superior analgesia to either drug alone. We evaluated 60 outpatients undergoing arthroscopic menisectomy under general anesthesia. After conclusion of surgery, patients were randomized into three groups: Group I received IA 20 mL 0.5% bupivacaine added to 10 mL 0.9% normal saline; Group II received IA 10 mL 10% magnesium sulphate [MgSO4] added to 20 mL 0.9% normal saline; Group III received IA 20 mL 0.5% bupivacaine added to 10 mL 10% magnesium sulphate [MgSO4]. This study revealed a significant benefit from the individual IA administration of both bupivacaine and magnesium sulphate. The combination of these drugs resulted in better postoperative analgesia as well as an increased analgesic duration compared with either drug alone. We conclude that IA magnesium sulphate and bupivacaine improved comfort compared with either drug alone in outpatients undergoing arthroscopic knee surgery. They increased time to first analgesic request, decreased need for postoperative analgesics, and lowered pain scores after arthroscopic knee surgery