Association Between Peripheral Nerve Blocks and Cardiovascular Outcomes in Older Adults with Hip Fractures

Background: Hip fractures in older adults carry substantial perioperative risk, with cardiovascular complications being a major concern. The dual physiologic stress from fracture and surgical repair activates neuroendocrine pathways and creates sympathovagal imbalance. While peripheral nerve blocks are established for analgesia in hip fracture management, their potential to attenuate the surgical stress response and reduce cardiovascular complications remains unclear. This study evaluated the association between peripheral nerve blocks and cardiac events in older adults undergoing hip fracture surgery. Methods: This cohort study used the Premier Healthcare Database, including patients aged 65 years or older with hip fractures surgically treated in 2022 or 2023. Peripheral nerve block administration was identified through procedure codes and pharmacy records. Propensity score matching (1:1) balanced baseline characteristics between groups. The primary outcome was myocardial infarction during index hospitalization. Secondary outcomes included other cardiac events and noncardiac complications. All-cause 90-day readmission was an exploratory outcome. Results: Among 23,812 eligible patients, 3,299 (14%) received peripheral nerve blocks. After propensity matching, each group contained 3,299 patients (median age 81 years). Myocardial infarction showed a protective point estimate but did not reach statistical significance (risk ratio [RR] 0.64; 95% confidence interval [CI]:0.37-1.12; p = 0.12). Nerve blocks were associated with reduced acute congestive heart failure (RR 0.47; 95% CI: 0.31-0.72; p < 0.001) and cardiac arrest (RR 0.41; 95% CI: 0.19-0.90; p = 0.03). Nerve blocks were also associated with a reduced risk of 90-day hospital readmission (RR 0.82; 95% CI: 0.72-0.93; p = 0.003). Conclusions: Peripheral nerve blocks were associated with reduced cardiovascular complications in older adults undergoing hip fracture surgery. While myocardial infarction rates were similar between groups, nerve blocks were associated with reduced in-hospital acute congestive heart failure and cardiac arrest. These findings are hypothesis-generating for cardioprotective effects from peripheral nerve blocks. Level of Evidence: Level III, Therapeutic. See Instructions for Authors for a complete description of levels of evidence.