In-hospital mortality in acute ischemic stroke treated with hemicraniectomy in US hospitals

Abstract

Hemicraniectomy is a surgical procedure performed to prevent cerebral herniation and death in patients who have sustained a massive ischemic stroke in the anterior circulation territory. Information on in-hospital mortality in patients with large ischemic stroke treated with hemicraniectomy outside randomized trials is lacking. We sought to identify in-hospital mortality associated with hemicraniectomy in a large US sample. We selected our cohort from the National Inpatient Sample database for the years 2000 through 2006 using the clinical classification software codes for acute ischemic stroke (AIS) and arterial occlusion, and identified those patients treated with thrombolysis or hemicraniectomy by the procedure codes. A multivariate logistic regression model was used for adjusted analysis. Among 502,231 patients with AIS, 252 (0.05%) underwent hemicraniectomy, and 7526 (1.5%) were treated with thrombolysis. Compared with the nonsurgical group, patients treated with hemicraniectomy were younger (mean age, 55.6 vs 71.5 years) and had lower Charlson Comorbidity Index scores (92.8% vs 76.0%). The mortality rate was higher in the hemicraniectomy group (32.1% vs 10.8%; adjusted odds ratio [OR] = 3.91; 95% confidence interval [CI] = 2.97-5.16). In patients treated with thrombolysis, mortality was higher in the hemicraniectomy group compared with the nonsurgical group (35.3% vs 13.1%; P = .01). The rate of hospital utilization of hemicraniectomy varied between 0.04% and 0.06% among all stroke admissions; the trend did not change significantly over the 7-year study period (P = .06). The mortality rate in hemicraniectomy-treated patients was significantly lower than in historical cohorts however, hemicraniectomy remains associated with high in-hospital mortality. The rate of utilization of hemicraniectomy for AIS in US hospitals has remained essentially unchanged.