RESUMEN
Propofol is an intravenous agent used extensively in total venous anesthesia [TIVA], but its acquisition cost is nearly 1 to 3 folds higher than other intravenous or inhalation agents. Thiopental is an ultra short acting barbiturate which can reduce the cost of induction to one seventh of Propofol induction cost. In this study, by BIS monitoring of the depth of anesthesia, we evaluated maintaining anesthesia with Propofol while Thiopental has been used for induction of anesthesia and the aim of study was to find a cost effective method. In a single blind clinical trial, 82 patients with ASA II and I scheduled for cataract surgery were randomized in two groups. In the first group [A], induction of anesthesia was done with Propofol 2 mg/kg and then anesthesia maintained with Propofol 100 micro/kg. In the other group [B], induction was Thiopental 5 mg/kg and anesthesia maintained with Propofol 160 micro/ kg. BIS monitored depth of anesthesia throughout the procedure. We compared the BIS values in each step of the procedure in both groups. After extubation, mean of BIS score were 87.53[ +/- 2.52] and 88.79[ +/- 2.07] for groups A and B respectively. This difference was not clinically significant. Multiple linear regression analysis, identified decreased maintenance dose of Propofol and duration of surgery as independent predictors for BIS span 40-60.[P < 0.000,r[2] =0.558]. Cost effectiveness [acquisition cost/percent of 40-60 BIS span] for groups A and B were 2.95 S and 1.03 S respectively. Minor surgeries like ophthalmic surgery can be conducted with maintenance of Propofol while induction is with Thiopental. Monitoring the depth of anesthesia with BIS showed that if we choose 160 micro/kg Propofol for maintenance then it is not necessary to have a loading dose and induction can be done by Thiopental. Further studies with different type of surgery and different maintenance doses of Propofol must be done
RESUMEN
The injection of retrobulbar block is associated with significant pain and discomfort. Therefore a short-acting IV analgesic before retrobulbar injection has been advocated. To compare remifentanil, alfentanil and fentanyl in providing analgesia for retrobulbar block injection. 69 patients were enrolled randomly into three groups of 23 each to receive either Remifentanil 1 micro g/kg, Alfentanil 20 micro g/kg or Fentanyl 2 microg/kg as an IV bolus dose prior to retrobulbar injection. Mean arterial pressure [MAP] and heart rate [HR] were recorded and Numerical Pain Score [NPS] were assessed by a blinded observer. Remifentanil prevented increase in MAP and HR while alfentanil and fentanyl were ineffective in this purpose [p < 0.05]. NPS was significantly lower in remifentanil group [p < 0.05]. Remifentanil 1 microg/kg prior to retrobulbar injection provide excellent hemodynamic stability and ensure analgesia