Journal of AdvancedMedical and Dental Sciences Research

The ratio of the dosage required for irreversible cardiovascular collapse (CC) and the dosage that will produce CNS toxicity (convulsions), is lower for Bupivacaine than lignocaine. Ventricular arrhythmias and fatal ventricular fibrillation may occur after rapid intravenous administration of a large dose of Bupivacaine but not lignocaine. Detailed pre-anesthetic evaluation was done. Patient fulfilling the essential criteria are selected and are allocated to each of the 2 groups, Group S- supine position and Group L- Lateral table tilt, by computer generated random numbers. All patients are preloaded with Ringer's lactate solution (10 ml kg-1) along with premedication of Metoclopramide (10 mg) i.v., Ranitidine (50) mg i.v., 15 minutes prior to surgery. When the series is studied as a whole, there is no statistically significant difference in baseline values of systolic and diastolic blood pressure between the two groups in both sitting and supine posture. This is shown in the table above. However, in 7 patients each of both group L and S, there was more than 20% fall in blood pressure, on change of posture from sitting to supine.