Effect of fentanyl on efficacy of low-dose ropivacaine for spinal anesthesia in patients undergoing anorectal surgery / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the effect of fentanyl on the efficacy of low-dose ropivacaine for spinal anesthesia in patients undergoing anorectal surgery.Methods Forty ASA Ⅰ or Ⅱ patients,aged 20-55 yr,with body mass index 18-28 kg/m2,scheduled for anorectal surgery,were randomly divided into 2 groups (n =20 each)0.5％ ropivacaine 7.5 mg group (group R) and 0.3％ ropivacaine 6.0 mg+ fentanyl 10 μg group (group RF).A catheter was implanted into the subarachnoid space (L3.4 interspace) and advanced caudally until lumbar region.Group R received hyperbaric 0.5％ ropivacaine 1.5 ml.Group RF received 2.0 ml mixture of hyperbaric 0.3％ ropivacaine 6.0 mg and fentanyl 10μg.The onset time of sensory and motor block,upper level of sensory block,and duration of sensory and motor block were recorded.Motor block was assessed by modified Bromage scale.Results Compared with group R,the duration of sensory and motor block was significantly shortened,and modified Bromage scores were significantly decreased in group RF (P ＜ 0.05 or 0.01),and no significant change was found in the onset time of sensory and motor block and upper level of sensory block between the two groups (P ＞ 0.05).Conclusion 0.3 ％ ropivacaine 6.0 mg combined with fentanyl 10 μg provides satisfactory spinal anesthesia for anorectal surgery,with lower degree and faster recovery of motor block.