Time to surgery and outcomes in patients with head injury

Abstract

Head injury is a time-sensitive trauma requiring rapid diagnosis, aggressive surgical evaluation, and prevention of secondary insults. However, studies examining the benefits of timely surgery in patients with head injury have yielded inconsistent conclusions. This study examined predictors of time to surgery and how time influenced three patient outcomes: hospital mortality, length of hospital stay (LOS), and discharge disposition to home rather than another facility. The Quality Health Outcomes Model was utilized as a conceptual framework for the study. Using a multivariate, cross-sectional design, the study took advantage of the National Trauma Data Bank (NTDB) version 4.0. This database was established by the American College of Surgeons Committee on Trauma (ACSCOT), and included data from more than 255 trauma centers throughout the U.S. that voluntarily submitted data. The final sample of head injured patients that met inclusion criteria was 493 patients from the 17 level I and II trauma centers. The factors influencing time to surgery included patient characteristics (e.g., age, Glasgow coma scale (GCS) score, injury severity score (ISS), emergency department (ED) arrival time), and trauma center characteristics (e.g., ownership, teaching status, designation type, center level). Two-level hierarchical models were used to analyze data at the patient level while incorporating a unique random effect for each trauma center. Patients with a GCS score of 3 to 8 in the first ED assessment had earlier time to surgery when compared to those with a GCS of 13 to 15 (Estimate = -.305, 95% CI = -.434 to -.177). Patients who arrived at the hospital during the daytime (8am-6pm) had a significantly quicker time to surgery than those who arrived during the nighttime (Estimate = -.147, 95% CI = -.258 to -.036). With regard to outcomes, patients who received surgery within 4 hours of arrival had half the likelihood of mortality when compared to those who received surgery greater than 4 hours after ED arrival (OR = .498, 95% CI = .246 to .999). When patients had a surgery within 4 hours of arrival, they had significantly shorter LOS than patients who had a surgery more than 4 hours (Estimate = -.103, 95% CI = -.194 to -.012). No significant relationship was found between time to surgery and discharge to home, a proxy for better functional status. Based upon the results of this study using a large sample from multiple centers, benefits of early clinical assessment and quick access to neurosurgical intervention are substantiated. However, more complete data representing pre-trauma center care (e.g., ambulance time and treatment) and discharge functional measure are desirable.