Comparative Evaluation of Post Operative Urinary Retention of Intrathecal Bupivacaine and Ropivacaine in Lowerlimb Orthopaedic Surgeries

Background and Aims: Inability to void urine post spinal anaesthesia is always worrisome factor. Present study of bupivacaine 0.5% (12.5mg) 2.5ml versus ropivacaine 0.75% (18.75mg) 2.5ml in equianalgesic doses was taken to observe the correlation of time to void urine and time for functional recovery. Methods: We studied forty adult male patients of ASA1 and 11, and assigned to two groups (bupivacaine/ropivacaine) for receiving SA for lower limb elective orthopaedic surgeries, lasting up to 60 mins. Post op patients monitored and time noted when patient voided the urine, in case of inability to void with full bladder sensation or observation of distended bladder by palpation then urinary catheterization done and time noted and data was analysed with SPSS 22.0 for windows software. Results: Both groups were comparable in terms of time to void (6.0 � 1.3 vs.5.0 � 1.3 h; P greater than 0.05), Height of sensory block at 20 mins (T10: T8: T6: T4) 5: 7: 8: 0 vs 2: 8: 10: 0; Complete motor block (modified Bromage grade 3 in mins) of SA 9.3 � 3.1 vs. 9.2 � 1.9 grade; P greater than 0.05), Duration of motor block (85�8.2 vs 70�5.1) time to complete ambulation (6.7 � 1.3 vs. 6.0 � 1.0 h; P greater than 0.05), respectively. Two patients from bupivacaine group required catheterization after 6.5 hrs past surgery due to restlessness. Conclusion: Our study concluded that Bupivacaine delays bladder emptying than ropivacaine when bupivacaine and ropivacaine were used in doses of 12.5mg and 18.75mg.