A study of the effect of aminophylline on clinical recovery and bis readings after total intravenous anesthesia

Background: In anesthesia and intensive care we face a lot of respiratory problems that require the use of bronchodilators such as aminophylline which is accused of antagonizing of the action of adenosine which acts as neuromodulator in the CNS. Objective: To test the hypothesis that aminophylline increases BIS readings and decreases recovery time after total intravenous anesthesia. Methods: We tested the hypothesis on 50 patients who were to be operated upon for orthopedic procedures. We induced anesthesia using bollous dose of propofol 2.5 mg/kg and bollous remifentanil 1.5 mcg/kg and didn't use any muscle relaxant. Anesthesia was maintained using propofol and remifentanil infusion in the rate of 100 mcg/kg/min and 0.2 mcg/kg/min respectively with 100% O2 with BIS readings in the range of 40 - 60. After skin closure, patients were divided into group A (given aminophylline 4 mg/kg), and group P (given same volume of normal saline). Vital signs and BIS values were recorded. Time to eye opening and extubation time and time to reach BIS value of 95 were measured. Results: Significant difference was found in BIS readings (p value < 0.001). Time to eye opening and extubation times were significantly shorter in group A than group P (p value < 0.001). Conclusion: Aminophylline decreases recovery time and increases BIS readings after TIVA.