Chemical hip denervation using phenol via Pericapsular Nerve Group (PENG) block in palliative non-operative management for frail older hip fracture patients: A multicenter retrospective cohort study.

Effective analgesia is critical yet challenging in non-operative management (NOM) of hip fractures for frail older patients in the palliative setting. Chemical hip denervation with phenol via PEricapsular Nerve Group (PENG) block has been applied to improve pain management. This is the first multicenter retrospective study that evaluated pain experience, opioid consumption and mobility in this population. The study included 185 patients, aged 70 years or older, who received chemical hip denervation with phenol via PENG block in the context of NOM from January 2022 until August 2023 in six hospitals across the Netherlands. Patient data were extracted from electronic health records. Patients were aged median 87 years (p25 - p75 82-91) with multiple comorbidities, the majority suffered from cognitive impairment (74 %) and depended on daily care (88 %). Phenol was mostly used with a concentration of 6 % (70 % of patients) or 10 % (23 % of patients) and a median volume of 10 ml (p25 - p75 8-10). Post procedural pain was experienced as acceptable in the majority of patients (89 % rest-related, 65 % care-related). The secondary outcomes of pain on a numeric rating scale (NRS) and morphine milligram equivalents (MME) were low. However, mobility remained limited. Median survival was 9 days (p25 - p75 4-22). Significant differences were observed in fracture type and hospital location. No complications or adverse treatment effects were reported. Chemical hip denervation with phenol via PENG block may be a viable analgesic option in selected frail older hip fracture patients as part of person-centered, multidisciplinary palliative care. Study limitations included its retrospective design with unavailable data on quality of life. Future prospective studies should evaluate patient outcomes. Further research is necessary to define optimal techniques, phenol percentage and volumes and reduce practice variability.