Background: Adequate intraoperative analgesia combined with faster mobilization might be achieved by replacing hyperbaric ropivacaine partly with fentanyl.
Methods: Sixty spinal anesthesia patients were randomized into 2 groups of either fentanyl 20 microg mixed with hyperbaric ropivacaine 10 mg (group FR10) or hyperbaric ropivacaine 15 mg (group R15). Forty-five patients underwent inguinal hernia repair and 15 patients had lower extremity surgery. Sensory block was tested by pinprick, and motor block was tested by use of a modified Bromage scale at 5-minute intervals for 30 minutes, 15-minute intervals for 60 minutes, and at 30-minute intervals until full recovery.
Results: The groups did not differ significantly regarding success (27 of 30 [group FR10] and 29 of 30 [group R15]), median onset time (10 [5 to 25] v 10 [5 to 20] minutes) or median duration of T10 sensory block (55 [20 to 115] v 80 [5 to 170] minutes), respectively. Recovery from spinal block was significantly quicker in group FR10 than in group R15, recorded in ability to walk (2.5 hours v 3 hours [P=.017]), full motor recovery (1 hour v 1.5 hour [ P <.001]), and sensory recovery to S1 (2.5 hours v 3.3 hours [ P=.026]). Pruritus occurred in 18 (60%) of group FR10 v 0 of group R15 patients ( P <.001). This symptom was mild in all except 1 patient, who received ondansetron 8 mg IV. In the OR, the groups did not differ hemodynamically: 9 (30%) of the group FR10 and 10 (33%) of the group R15 patients, respectively, required medication for hypotension and/or bradycardia. Full motor block (Bromage 3) developed less frequently (P <.001) in group FR10 patients than in group R15 patients (1 [3%] v 14 [47%]), and the group FR10 patients recovered faster in a median time of 60 v 90 minutes (P <.001). In both groups, sensory and motor blocks were more extensive on the operative side compared with the nonoperative side ( P <.001).
Conclusion: Faster mobilization but equal onset and duration of analgesia were achieved with intrathecal hyperbaric ropivacaine 10 mg plus fentanyl 20 microg as compared with hyperbaric ropivacaine 15 mg.