Background — There is consistent and significant variation in neuraxial anesthesia use for hip fracture surgery across jurisdictions. We measured the association of hospital-level utilization of neuraxial anesthesia, independent of patient-level use, with 30-day survival (primary outcome) and length of stay and costs (secondary outcomes).
Methods — We conducted a population-based cohort study using linked administrative data in Ontario, Canada. We identified all hip fracture patients more than 65 yr of age from 2002 to 2014. For each patient, we measured the proportion of hip fracture patients at their hospital who received neuraxial anesthesia in the year before their surgery. Multilevel, multivariable regression was used to measure the association of log-transformed hospital-level neuraxial anesthetic-use proportion with outcomes, controlling for patient-level anesthesia type and confounders.
Results — Of 107,317 patients, 57,080 (53.2%) had a neuraxial anesthetic; utilization varied from 0 to 100% between hospitals. In total, 9,122 (8.5%) of patients died within 30 days of surgery. Survival independently improved as hospital-level neuraxial use increased (P = 0.009). Primary and sensitivity analyses demonstrated that most of the survival benefit was realized with increase in hospital-level neuraxial use above 20 to 25%; there did not appear to be a substantial increase in survival above this point. No significant associations between hospital neuraxial anesthesia-use and other outcomes existed.
Conclusions — Hip fracture surgery patients at hospitals that use more than 20 to 25% neuraxial anesthesia have improved survival independent of patient-level anesthesia type and other confounders. The underlying causal mechanism for this association requires a prospective study to guide improvements in perioperative care and outcomes of hip fracture patients.