Haemodynamic Effects of Unilateral Spinal Anaesthesia With Low Dose of 0.5% Hyperbaric Bupivacaine- A Clinical Study

Abstract

BACKGROUND Unilateral spinal anaesthesia is a promising alternative to traditional, widely used techniques of central neuraxial blocks. Present study was taken up to assess haemodynamic effects, level achieved and duration of block with low dose 0.7 mL (3.5 mg) of 0.5% hyperbaric Bupivacaine. MATERIALS AND METHODSThis is a one year hospital-based cross-sectional study on a total of 100 patients undergoing unilateral lower limb surgery under unilateral spinal anaesthesia. 0.7 mL (3.5 mg) of 0.5% bupivacaine heavy was injected with patient in lateral position at L3-4 space with the limb to be operated on the dependent side. Patients were maintained in lateral position for 20 minutes and then made supine. Haemodynamic parameters SBP, DBP, MBP and HR were recorded. Sensory and motor block was evaluated. RESULTSIn this study out of 100, 72 were males. Mean age was 47.79 ± 13.91 years and mean weight was 57.90 ± 8.56 kgs. SBP, DBP and MBP decreased with maximum fall noted at 40 minutes and gradually increased, subsequently reaching the baseline levels at 90 minutes. Maximum increase in HR was seen at 40 minutes after giving spinal and it gradually reduced coming to baseline levels at 90 minutes. Maximum sensory level of L1 was achieved. The block remained unilateral in all the cases. Motor blockade was adequate in the limb to be operated. CONCLUSIONSubarachnoid block with 0.7 mL (3.5 mg) of 0.5% hyperbaric bupivacaine used in this study does not produce any adverse haemodynamic changes and lasts for short duration that is 90 minutes and can be used in surgeries of shorter duration. KEY WORDSVery Low Dose Hyperbaric Bupivacaine; Unilateral Spinal Anaesthesia. HOW TO CITE THIS ARTICLE: Shreedevi Y, Vandana G, Sanikop CS. Haemodynamic effects of unilateral spinal anaesthesia with low dose of 0.5% hyperbaric bupivacaine-a clinical study. BACKGROUNDSpinal anaesthesia is commonly used in anaesthetic practice, although the undesirable sequels related to this technique are well known. In the majority of cases spinal anaesthesia is accompanied by a decrease in arterial pressure; bradycardia, due to blockage of preganglionic sympathetic fibres. The incidence of hypotension depends upon number of factors such as the extent of subarachnoid blockage, age, associated coexisting disorders, presence of medication like ßadrenergic receptor blockers etc. 1,2 Moreover, the sympathetic blockage is often accompanied by uncontrolled hypothermia, especially at low environmental temperature. 3 Unilateral spinal anaesthesia is a promising alternative to traditional, widely used techniques of central neuraxial blocks as it restricts markedly the anaesthetised area, thereby decreasing the risk of adverse events and complications.