Hematoma block or procedural sedation and analgesia, which is the most effective method of anesthesia in reduction of displaced distal radius fracture?

BACKGROUND: Procedure sedation and analgesia (PSA) is often used to alleviate discomfort and to facilitate fracture reduction for patients with distal radius fracture in emergency departments and clinics, but risks of respiratory distress and needs for different levels of monitoring under PSA are still under concern. Hematoma block (HB) is a simple alternative method of providing rapid pain relief during reduction of distal radius fracture. However, there is still in lack of strong evidence to promote HB over PSA in clinical practice. The aim of this study was to compare HB and PSA for adult and pediatric patients during reduction of displaced distal radius fracture to identify the level of pain relief, frequency of adverse effects (AEs), and reduction failure.

METHODS: The PubMed, ScienceDirect, Cochrane Library, and ClinicalTrials.gov were searched for studies comparing HB or PSA in distal radius fracture reduction. The search revealed four randomized controlled trials and one non-randomized trial, which included two studies of pediatric subjects and three studies of adult subjects. Subgroup meta-analysis for adult and pediatric groups were specifically performed according to age difference to avoid potential bias.

RESULTS: In the adult group, the effect of HB on post-reduction pain severity was better than that of PSA with significant heterogeneity (Hedges' g - 0.600, 95% confidence interval (CI) - 1.170 to - 0.029, p = 0.039), although there was no difference on the pain severity during reduction between these two groups with significant heterogeneity (Hedges' g 0.356, 95% CI - 1.101 to 1.812, p = 0.632). In the pediatric group, the treatment effect on pain severity was significantly better by HB than that by PSA but without significant heterogeneity (Hedges' g - 0.402, 95% CI - 0.718 to - 0.085, p = 0.013, I 2  < 0.001%). Most of the reported adverse effects (AEs) include nausea, vomiting, and respiratory distress developed in adult patients treated by PSA. The rates of reported AEs did not significantly differ between HB and PSA in the pediatric group. Additionally, final outcomes of reduction failure did not significantly differ between HB and PSA in both adult and pediatric groups.

CONCLUSION: Hematoma block is a safe and effective alternative of anesthesia in reduction of distal radius fracture without inferior pain relief compared with PSA among adult and pediatric patients.