ABSTRACT
Bispectral index (BIS) monitoring may assist reduction in utilisation of anaesthetic agents during general surgical procedures. This study was designed to test whether the use of BIS monitoring reduces the anaesthetic requirements during off-pump coronary artery bypass grafting (CABG). This prospective - clinical trial was conducted on 40 adult patients undergoing elective off-pump CABG. Patients received either isoflurane or propofol anaesthesia. BIS monitoring, which guided the dose of anaesthetic, was carried out in 50 percent of the patients. The amount of anaesthetic agent (isoflurane or propofol) administered from the start of anaesthesia to the end of surgical procedure was calculated and were compared in four groups of patients - namely Group A (I-no BIS) received isoflurane; end tidal concentration was maintained at 1-1.2% in a low flow technique throughout the procedure, Group B (I-BIS) received isoflurane in a low flow technique; inspired concentration was dictated by BIS value maintained at 50; Group C (P-no BIS) received propofol at a dose range of 4-8 mg/kg/hr and in Group D(P-BIS) the propofol infusion rate was dictated by BIS value maintained at 50. The quantity of isoflurane was significantly less for Group B (I-BIS) as compared with Group A (I-no BIS) (37 +/- 4 vs. 24 +/- 4 ml; p< 0.05) and similarly the amount of propofol infused was significantly less in Group D (P-BIS) as compared with Group C (P-no BIS) (176 +/- 9 vs. 120 +/- 6 ml; p< 0.05). BIS guided anaesthesia reduces the anaesthetic agent required for the performance of off-pump CABG. This can be extrapolated in terms of saving agent and reduced cardiac depression during off-pump CABG.
Subject(s)
Anesthesia/methods , Anesthetics, Inhalation/administration & dosage , Anesthetics, Intravenous/administration & dosage , Coronary Artery Bypass, Off-Pump/methods , Dose-Response Relationship, Drug , Feasibility Studies , Female , Humans , Isoflurane/administration & dosage , Male , Middle Aged , Monitoring, Physiologic/methods , Propofol/administration & dosage , Prospective Studies , Elective Surgical Procedures/methodsABSTRACT
The efficacy of ultra-low-dose-aprotinin (ULDA) in 'high-risk' two valve replacement surgery, was evaluated in this prospective, randomized, double-blind study. Forty adult high-risk patients undergoing elective two valve replacement surgery, were included. The patients were divided into 2 groups of 20 each. In Group I, aprotinin in a dose of 1,000,000 KIU was administered from the end of anaesthesia induction to the time of sternotomy after a 1 ml of test dose. In Group II (control), 100 ml of normal saline was administered in a similar fashion. Coagulation parameters, blood loss, and amount of transfusion of blood / blood products were measured at specific intervals. The postoperative chest tube drainage in the first 24 hours was significantly less 203+/-35 ml (p<0.05) in Group I as compared with 490+/-104 ml in group II and consequently, Group I patients received significantly less (p<0.05) red cell concentrates and platelet transfusion. There was a significant decrease in the length of postoperative elective ventilation, intensive care unit (ICU) stay and direct costs involved in the hospital expenses with the use of ULDA. We conclude that ULDA is safe and effective in 'high-risk' two-valve replacement surgery to reduce postoperative bleeding, postoperative length of intubation and ICU stay; use of ULDA is associated with significant direct cost savings.