Anesthesia & Clinical Research
Open Access

The Pericapsular Nerve Group Block for Hip Fracture Surgery: A Prospective Case Report

Brigid Brown^1*, D-Yin Lin¹, Alex Saies², Marthinus Vermeulen¹, Hidde M. Kroon^3,4, Job Doornberg² and Ruurd Jaarsma^{2 *}Correspondence: Dr. Brigid Brown, Department of Anesthesiology, Flinders University and Flinders Medical Centre, Bedford Park, Australia, Email:

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Introduction

Neck of Femur (NOF) fracture is a painful condition associated with significant morbidity and mortality [1]. Femoral nerve block is commonly performed as part of multimodal analgesia [2-5]. However shows only modest reductions in pain scores and opioid requirement and results in temporary quadriceps weakness, contributing to delayed mobilization, prolonged hospital stay and in-hospital falls [6-10].

An anatomical study exploring the sensory innervation of the hip joint led to the development of the Pericapsular Nerve Group (PENG) block. This technique suggests greater improvement in pain scores and less motor weakness than the traditional femoral nerve blocks. Current literature on PENG blocks is limited to small case series and editorials only. This case series was designed to evaluate the PENG in a larger patient cohort than previously studied with a focus on pain score reduction in patients undergoing surgical NOF fracture repair.

Case Report

Study design

This is a single-center case series conducted at a large tertiary trauma centre. A prospective cohort of patients undergoing NOF fracture repair were enrolled and received a PENG block prior to their operation. The study was approved by the local ethics committee (AUD/19/SAC/197) in October 2019 and written informed consent was obtained. The primary outcome measure was individual patient pain score reduction. Secondary outcome measures were opioid consumption for the first three days postoperatively, complication rates, patient satisfaction and duration of block effect.

Participants

Three consultant anesthesiologists were trained in performing the PENG block (BB, DL, MV). Twenty-eight patients were recruited between October 2019 and April 2020. Inclusion criteria were age greater than 44 years, and planned NOF surgery. Exclusion criteria were contraindications to a regional nerve block, a distracting second injury, and patient’s refusal of a regional nerve block. Eligible patients were identified prospectively from these particular anesthesiologists’ orthopaedic operating lists. Per patient, a pain score difference was calculated by subtracting the maximum pain score postoperatively in Recovery from the maximum pre-operative pain score.

Results

Twenty eight patients were included in this study. The median age of patients was 78 years (range 59-99). Demographics are detailed (Table 1). Preoperatively, three patients (14%) had no to mild pain (VNRS 0-4), seven had moderate pain (VNRS 5-7), and 12 patients (54%) reported severe pain (VNRS 8-10).

Table 1: Patient and preoperative characteristics.

Postoperative outcomes are outlined (Table 2). At four hours postoperative, patients reported a median decrease in preoperative to postoperative pain of 7 points (range -3 to 10). 15 patients (65%) reported a pain scale of zero at 4 hours postoperative. The median length of stay in hospital was 6 days (range 2-49).

Table 2: Postoperative outcomes.

Postoperative opioid use and patient satisfaction scores are reported (Table 3). Every patient in this study required postoperative opioids and use was relatively consistent across all three days of follow up. The median duration of the PENG block was 12.5 hours (range 5.25-23 hours) as recalled by 20 patients. All patients in this subanalysis (n=20) reported they were satisfied with the PENG block and would have it again.

Table 3: Postoperative opiate use and patient satisfaction.

Conclusion

This PENG block case series demonstrates some potential advantages compared with the conventional nerve blocks used for analgesia in NOF fracture patients, however, further studies are required. This cohort study supports future randomised prospective trials in a larger patient group.

Acknowledgments

None

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