Objective: The authors sought to analyze a large, publicly available, nationwide hospital database to further elucidate the impact of cardiopulmonary arrest (CA) in association with subarachnoid hemorrhage (SAH) on short-term outcomes of mortality and discharge disposition.
Methods: This retrospective cohort study was conducted by analyzing de-identified data from the National (Nationwide) Inpatient Sample (NIS). The publicly available NIS database represents a 20% stratified sample of all discharges and is powered to estimate 95% of all inpatient care delivered across hospitals in the US. A total of 170,869 patients were identified as having been hospitalized due to nontraumatic SAH from 2008 to 2014.
Results: A total of 5415 patients (3.2%) were hospitalized with an admission diagnosis of CA in association with SAH. Independent risk factors for CA included a higher Charlson Comorbidity Index score, hospitalization in a small or nonteaching hospital, and a Medicaid or self-pay payor status. Compared with patients with SAH and not CA, patients with CA-SAH had a higher mean NIS Subarachnoid Severity Score (SSS) ± SD (1.67 ± 0.03 vs 1.13 ± 0.01, p < 0.0001) and a vastly higher mortality rate (82.1% vs 18.4%, p < 0.0001). In a multivariable model, age, NIS-SSS, and CA all remained significant independent predictors of mortality. Approximately 18% of patients with CA-SAH survived and were discharged to a rehabilitation facility or home with health services, outcomes that were most predicted by chronic disease processes and large teaching hospital status.
Conclusions: In the largest study of its kind, CA at onset was found to complicate roughly 3% of spontaneous SAH cases and was associated with extremely high mortality. Despite this, survival can still be expected in approximately 18% of patients.
Keywords: SAH; cardiac arrest; subarachnoid hemorrhage.