European Journal of Biomedical and Pharmaceutical Sciences

INTRATHECAL MORPHINE FOR POSTOPERATIVE ANALGESIA IN POSTERIOR LUMBAR SPINE DECOMPRESSION AND INSTRUMENTATION: A COMPARATIVE STUDY OF TWO DIFFERENT DOSES.

Dr. Priyanka Dhir*

ABSTRACT

Background: Patients undergoing lumbar spine instrumentation surgery suffer severe postoperative pain which is difficult to treat by conventional multimodal analgesic methods. In this randomized double blind study we compared the analgesic effect of two different doses of intrathecal morphine (ITM) 0.2 mg and 0.3 mg in patients undergoing posterior lumbar spine decompression and instrumentation surgery. Materials and Methods: Forty ASA 1 and 2 patients of either sex aged 18 years or older undergoing posterior lumbar spine decompression and instrumentation surgery between L1-L5 were randomly assigned to receive ITM either 0.2 mg (Group A, n=20) or 0.3 mg (Group B, n=20) in 2 ml saline before general anaesthesia. A morphine intravenous patient controlled analgesia (PCA) device was used for rescue analgesia in postoperative period. Assessment parameters included hemodynamics, sedation score, pain using numeric rating scale (NRS), total consumption of PCA morphine recorded for 24 hours and patient‟s satisfaction score. The data was analyzed using chi square test for categorical variables and student‟s t test for quantitative variables. Result: NRS score was significantly low in group B at 4, 8, 12 and 24 hours as compared to group A (p < 0.05). Group B also had decreased requirement for rescue analgesia (p = 0.001) with higher patient satisfaction. There was no significant difference between the two groups in other studied parameters. Conclusion: 0.3 mg ITM provided superior analgesia postoperatively in terms of NRS score and higher patient satisfaction compared with 0.2 mg with no significant difference in the incidence of side effects.

Keywords: Morphine, Intrathecal, Spine surgery, Patient controlled analgesia.