RESUMEN

Design: Prospective, randomized, controlled trial. Patients. Sixty-three adult patients with an American Society of Anesthesiologists Status I-III who are undergoing elective primary total hip arthroplasty. Interventions. Patients were randomized to the control group (no block) or the ESPB group (preoperative ultrasound-guided lumbar ESPB). Intraoperatively, all patients received spinal anesthesia with moderate sedation. Postoperatively, patients received a standardized multimodal analgesia protocol. Measurements. The primary outcome was cumulative opioid consumption at 24 hours postoperatively. Secondary outcomes included cumulative opioid consumption at 8 hours and through 48 hours postoperatively and pain scores at 24 and 48 hours post surgery. Main Results. Thirty-one patients were randomized to the control group (spinal alone) and 32 patients to the ESPB group. The median opioid requirement in the first 8 hours after surgery was higher in the control group (28 mg of oral morphine equivalents (OME) versus 5 mg of OME in the ESPB group) (p = 0.013). There was no statistically significant difference in opioid consumption between the groups at 24 hours (p = 0.153) or 48 hours (p = 0.357) postoperatively. There was no statistically significant difference in pain scores between the two groups through 24 hours (p = 0.143) or 48 hours (p = 0.617) after surgery. Conclusion: Lumbar ESPB reduces opioid utilization during the first 8 hours postoperatively after total hip arthroplasty but not thereafter. Evaluating the use of either adding a local anesthetic adjunct to the ESPB or using longer-acting local anesthetic warrants further investigation.