Ultrasound-guided pericapsular nerve group (PENG) blocks are safe and effective.

Introduction: Ultrasound-guided pericapsular nerve group (PENG) blocks are a type of regional nerve block that has gained increasing popularity for providing effective analgesia in patients with hip fractures. This retrospective case series evaluated the safety and effectiveness of Ultrasound-Guided PENG blocks using Ropivacaine 0.2% performed by emergency physicians in a single institute. Patients were enrolled between May 2019 and June 2021. The procedure was performed by emergency medicine attendings and ultrasound fellows. The patients were part of a convenience sample, with the procedure performed when an attending physician or ultrasound fellow was present in the emergency department and available to perform the procedure.

Methods: We conducted a single-center retrospective analysis of 13 PENG blocks performed by emergency medicine attendings and ultrasound fellows. This was done at our emergency department, which sees approximately 90,000 patients per year. All patients received between 1 and 3 mg/kg of Ropivacaine 0.2% with a max dosage of 120 mg (60 cc). Patient demographics, procedural details, complications, and pain outcomes were recorded.

Results: There is a significant mean (p = 0.007) reduction in pain level of 2.9 when comparing the post-test measurements to the pre-test measurements. This was confirmed by a non-parametric approach, which also found a significant reduction in the median difference (p = 0.009). This was further explained by a non-significant Shapiro-Wilk test, which found no significant evidence of non-normality (p = 0.499). (see Table 1). Among the 13 PENG blocks performed, there were no complications. Examples of known complications of regional nerve blocks include local anesthetic systemic toxicity (Barrington and Kluger 38:289-299, 2013;El-Boghdadly and 63:330-349, 2016;) paresthesias lasting more than 5 days ³; paresthesias lasting more than 6 months (Welch et al. 111:490-497, 2009); and permanent nerve injury³. None of the 13 blocks performed at our institution had complications.

Discussion: Our findings support the effectiveness and safety of ultrasound-guided PENG blocks performed by emergency physicians using Ropivacaine 0.2%. The high degree of pain relief and the absence of complications in our case series demonstrate that emergency physicians can perform PENG blocks with a high level of competency and safety.

Conclusion: This retrospective case series, conducted between May 2019 and June 2021, demonstrates the effectiveness and safety of ultrasound-guided PENG blocks performed by emergency physicians. The high rate of pain relief and lack of complications in our patients who received the PENG block demonstrates the benefits of this technique. We suggest that additional research and randomized controlled trials will help to validate these findings and support the increased use of PENG blocks in the emergency department for the treatment of hip fractures.