Association of Do-Not-Resuscitate orders and in-hospital mortality among patients undergoing cranial neurosurgery

Background: Previous studies identified pre-existing DNR orders as a predictor of mortality after surgery. We sought to evaluate mortality of patients receiving cranial neurosurgery with DNR orders placed at the time of, or within 24 h of admission.Methods: We performed a retrospective cohort study using the California State Inpatient Database, January 2018 to December 2020. We used International Classification of Diseases, 10th Revision (ICD-10) codes to identify emergent hospitalizations with principal diagnosis of brain injury, including traumatic brain injury [TBI], ischemic stroke [IS], intracerebral hemorrhage [ICH], subarachnoid hemorrhage [SAH], or malignant brain tumor [mBT]. We used procedure and Diagnosis Related Group codes to identify cranial neurosurgery. Patients with DNR were one-to-one matched to non-DNR controls based on diagnosis (exact matching), age, sex, Elixhauser comorbidity index, and organ failure (coarsened matching). The primary outcome was inpatient mortality.Results: In California, 30,384 patients underwent cranial neurosurgery, 2018-2020 (n = 3,112, 10% DNR). DNR patients were older, more often female, more often White, with greater comorbidity and organ system dysfunction. There were 2,505 patients with DNR orders 1:1 matched to controls. Patients with DNR had greater inpatient mortality (56% vs. 23%, p < 0.001; Hazard Ratio 3.11, 95% CI 2.50-3.86), received tracheostomy (Odds Ratio [OR] 0.37, 95% CI 0.24-0.57) and gastrostomy less (OR 0.48, 95% CI 0.39-0.58) compared to controls. Multivariable analysis of the unmatched cohort demonstrated similar results.Conclusion: Patients undergoing cranial neurosurgery with early or pre-existing DNR have high inpatient mortality compared to clinically similar non-DNR patients; 1 in 2 died during their hospitalization.