Systemic versus perineural dexamethasone as an adjuvant to bupivacaine in combined femoral and sciatic nerve blocks in lower-limb vascular surgeries: a prospective randomized study

Abstract

Background and aim Various peripheral nerve block techniques have been described to deliver anesthesia and analgesia that allow better functional recovery and shortened hospital stay following major lower-limb surgeries. We aimed to compare the possible effect of perineural dexamethasone versus systemic dexamethasone after nerve stimulator-guided combined femoral and sciatic nerve blocks in lower-limb vascular surgeries. Patients and methods After obtaining approval from the ethical committee of Kasr Al-Ainy University Hospital and obtaining written informed consent, 63 patients aged 18–70 years were randomly allocated into three equal groups. Group P received perineural dexamethasone plus bupivacaine 0.5%, group I received intravenous dexamethasone plus perineural bupivacaine 0.5%, and group B received perineural bupivacaine 0.5% alone. We compared the onset and duration of sensory and motor blockade, duration of analgesia, and hemodynamic changes. Results Sensory and motor block onset showed nonsignificant difference between the three groups. Sensory block duration was significantly longer in group P than in groups I and B. Motor block duration was significantly prolonged in groups P and I when compared with group B. Motor block duration was longer in group P than in group I; however, the difference was statistically nonsignificant (p-value 0.34). The duration of analgesia was significantly longer in group P than in the other groups, and significantly longer in group I compared with group B. Conclusion The use of equal doses of perineural or intravenous dexamethasone as an adjuvant in single injection combined femoral and sciatic nerve blocks is associated with extended duration of sensory and motor blocks, extension of postoperative analgesia duration, and reduced postoperative analgesic requirements.