Incidence of lower limb motor weakness in patients receiving postoperative epidural analgesia and factors associated with it: An observational study

INTRODUCTION AND AIM: Epidural analgesia is an effective technique for postoperative pain relief following thoracoabdominal surgeries. Lower limb motor weakness is a well-known complication of epidural analgesia with local anesthetics and delays postoperative rehabilitation. Our aim in conducting this observational study was to assess the frequency of lower limb motor weakness in patients receiving epidural analgesia following upper abdominal surgery and the factors associated with it. MATERIALS AND METHODS: All adult patients, aged 20-70 years, who underwent upper abdominal surgery and received postoperative analgesia with an epidural infusion of bupivacaine with fentanyl, were included. Data were collected over 4 months from notes entered by acute pain service after each round. Data collected included level of epidural placement, drug solution and volume, degree of lower limb motor weakness and measures taken to relieve it. Bromage scale was used to assess motor weakness. RESULTS: Data were collected on 123 patients. Bupivacaine 0.1% with fentanyl 2 μg/mL was used in 113 (92%) patients. Lower limb motor weakness developed in 45 patients (36.5%). The highest frequency was seen in patients with epidural at L2-L3 level. The common management steps were a change of patient's position or decrease in concentration of local anesthetic. These measures produced improvement in 39 (87%) patients whereas the local anesthetic was stopped temporarily in the remaining six patients. CONCLUSION: Lower limb motor weakness occurred in 36.5% patients. It was more common with a lumbar epidural. It was successfully managed in all patients. Lower thoracic epidurals are recommended for abdominal surgeries.