Title: THE EFFECT OF ADDING INTRATHECAL MAGNESIUM SULPHATE TO BUPIVACAINE-FENTANYL SPINAL ANAESTHESIA
Abstract: BACKGROUNDSpinal anaesthesia plays an important role of alleviating pain intraoperatively, extending into post-operative period also.Many drugs have been tried in search for an ideal adjuvant like opioids, soda bicarbonate, ketamine, neostigmine and midazolam.The magnesium sulphate with different mode of action prolong the Bupivacaine-Fentanyl spinal anaesthesia. MATERIALS AND METHODSThe study was conducted in 70 patients undergoing elective lower extremity surgeries.After routine preoperative assessment as for all elective surgery patients, they were premedicated and patients were randomly allocated into two groups.Group S received Inj.0.5% Bupivacaine 2 cc+Inj.Fentanyl 0.5 cc + 0.9% NaCl solution 1 cc, Group M received Inj.0.5% Bupivacaine 2 cc+Inj.Fentanyl 0.5 cc+50 mg of 5% MgSO4 1 cc.On preoperative visit, the patients were explained about the procedure details.Patients were put on sitting position and with strict aseptic precaution lumbar puncture was done.The assigned amount of drug is premixed in a sterile syringe was injected as per the group assigned.After injection patient were put up in supine position.After attaining adequate peak level of sensory block, the surgeon was asked to proceed.If needed oxygen was given through ventimask.The results were observed. RESULTSThe main finding of this study is that in patients undergoing lower extremity surgery under bupivacaine-fentanyl spinal anaesthesia, the addition of 50 mg IT MgSO4 led to a significant delay in the onset of both sensory and motor blockade and prolonged the duration of spinal anaesthesia without increasing side effects.The mean duration of spinal anaesthesia was significantly prolonged by magnesium to 209 mts.No case had respiratory depression intraoperatively as well as in post-operative period in this study.In this study, the respiratory rate remained unchanged with the baseline and the haemodynamics were stable in the magnesium group. CONCLUSIONFrom this study it was concluded that in patients undergoing lower extremity surgery, IT MgSO4 (50 mg), when added to spinal anaesthesia induced by bupivacaine and fentanyl, delayed the onset of both sensory and motor blockade and prolonged the duration of anaesthesia without increasing the incidence of side effects.