ObjectivesThe primary objective was to compare the analgesic efficacy of Ultrasound‐guided Erector Spinae Plane block (ESPB) with a sham procedure in adult patients presenting with rib fractures to the Emergency department (ED).MethodsA randomized controlled trial was conducted at an academic ED over a 17‐month period. Forty‐six adults with confirmed rib fractures and numeric rating score (NRS) greater than 4 were randomized to one of two treatment arms: ultrasound‐guided ESPB group or placebo (sham procedure). Intravenous opioids were prescribed as rescue analgesia when self‐reported pain scores were >/=4. The primary outcome measure, pain intensity reduction, was derived using the 11‐point NRS at six‐time points over 12 hours. Secondary outcome measures included the amount of rescue analgesia, in morphine equivalents, and the occurrence of adverse events. Two‐way repeated measures ANOVA was used to compare the trend in NRS scores across the two arms. The association between the complications and intervention was explored using the Fisher's Exact test.ResultsForty‐six patients (23 in each arm) completed the study. There was no difference between treatment groups with respect to age, sex, vital signs, pre‐enrolment analgesia, or baseline pain intensity. In comparing pain intensity during the study period, NRS scores at 30, 60 and 120 minutes were significantly lower in the ESPB group (p < 0.001) during rest and deep inspiration. Moreover, patients in the ESPB group received lesser rescue analgesia than those in the sham group (10 mg, IQR = 2.5 vs 20 mg, IQR = 5 mg; p = <0.01). There was no difference in adverse events between groups.ConclusionsUltrasound‐guided ESPB resulted in significantly reduced pain intensity over the study period, reduced amount of rescue analgesia, and had no discernible difference in adverse events when compared with a sham.