COMPARISON OF HAEMODYNAMIC EFFECTS OF UNILATERAL VERSUS BILATERAL SPINAL ANAESTHESIA

Abstract

Aim of Study: A comparative study was carried out to determine whether the unilateral spinal block produces comparatively less haemodynamic disturbances as compared to bilateral spinal block or not. Patients and Methods: Fifty male patients of age 25- 40 years of comparable weight and height, and ASA status I & II were selected and divided into two groups, Group A and Group B. Each group was assigned 25 patients by convenience sampling. Blood loss was comparable in both groups. All patients were assessed pre-operatively a night before operation. Two variables i.e. pulse and blood pressure was measured a night before operation, just before spinal injection and every thirty minutes for a total period of 180 minutes after the spinal injection. Average duration of surgical procedures was 57 +/- 13 minutes. Each patient was premedicated with tablet “Diazepam 10 mg” a night before operation and injection Diazepam 05 mg IV just before spinal injection and pre- loaded with 5% Dextrose Saline 500 ml. All patients were injected “abocaine spinal” 0.75% (heavy) 1.5 ml at L4-5 or L3-4 interspace intradurally with the help of 23G spinal needles under aseptic measures. Group-A patients were kept supine in flexed position for 10 minutes and Group B patients were kept in lateral decubitus position with surgical side down, for 10 minutes. Block was achieved up to T10-11 level. Contra lateral side was checked for block. Results: Two groups were clinically comparable as regard to patient characteristics and methods of study e.g. dose and type of drug used and level of anaesthesia achieved. There was no significant hypotension or bradycardia in any group; rather there was an increase in blood pressure and heart rate in few patients signifying sympathetic over activation in younger patients. Conclusion: In younger age group haemodynamic changes were negligible in either group of study most probably due to active sympathetic system at the unblocked area. Unilateral block could be a more useful concept in older age group and autonomically compromised patients.