Effects of isobaric ropivacaine with or without fentanyl in subarachnoid blockade: A prospective double-blind, randomized study

BACKGROUND: The addition of fentanyl to ropivacaine has shown to improve the quality of analgesia without compromising its benefits such as early mobilization and early voiding. AIM: The aim of the study was to evaluate the effects of the isobaric ropivacaine in combination with fentanyl and compare it with the isobaric ropivacaine alone in spinal anesthesia for lower abdominal and lower limb surgeries. SETTINGS AND DESIGN: Double-blinded randomized controlled trial. SUBJECTS AND METHODS: Hundred patients belonging to American Society of Anesthesiologists physical status I and II scheduled for either lower abdominal or lower limb surgery under spinal anesthesia were included. The study was a prospective double-blinded randomized controlled trial where patients were randomly allocated into two groups to receive either 2.5 ml of 0.75% (18.75 mg) isobaric ropivacaine with 25 μg fentanyl (Group RF) or 2.5 ml of 0.75% (18.75 mg) isobaric ropivacaine with 0.5 ml of 0.9% saline (Group R) intrathecally. STATISTICAL ANALYSIS: Data analysis was done by Student's unpaired t-test. SPSS version 16 was used. P < 0.05 was considered as statistically significant. RESULTS: We found no significant difference in hemodynamics, onset of sensory and motor block, peak level of block, recovery from motor block, return of micturition and incidence of side effects with the addition of fentanyl to ropivacaine. First request for analgesia was required earlier in the control group. There was also a significant prolongation of the duration of sensory block (mean - 341.6 min) and postoperative analgesia in Group RF (mean - 442.2 min) (P < 0.001). CONCLUSION: The addition of fentanyl to ropivacaine significantly prolongs the duration of postoperative analgesia with clinically insignificant influence on hemodynamics and motor blockade with minimal side effects.