The effect of craniectomy size on mortality, outcome, and complications after decompressive craniectomy at a rural trauma center

INTRODUCTION: Decompressive craniectomy (DC) has increasing support with current studies suggesting an improvement in both survival rates and outcomes with this intervention. However, questions surround this procedure; specifically, no evidence has indicated the optimal craniectomy size. Larger craniectomy is thought to better decrease intracranial pressure, but with a possible increase in complication rates. Our hypothesis is that a larger craniectomy may improve mortality and outcome, but may increase complication rates. MATERIALS AND METHODS: A retrospective observational therapeutic study was undertaken to determine if craniectomy size is related to complication rates, mortality, or outcome. Our institution's Trauma Registry was searched for patients undergoing DC. Craniectomy size was measured by antero-posterior (AP) diameter. Mortality, outcome (through admission and discharge Glasgow Coma Score and Glasgow Outcome Scale), and complications (such as re-bleeding, re-operation, hygroma, hydrocephalus, infection, and syndrome of the trephined) were noted. Complications, mortality, and outcome were then compared to craniectomy size, to determine if any relation existed to support our hypothesis. RESULTS: 20 patients met criteria for inclusion in this study. Craniectomy size as measured by AP diameter was correlated with a statistically significant improvement in mortality within the group. All patients with a craniectomy size less than 10 cm died. However, outcome was not significantly related to craniectomy size in the group. Similarly, complication rates did not differ significantly compared to craniectomy size. DISCUSSION: This study provides Level 3 evidence that craniectomy size may be significantly related to improved mortality within our group, supporting our initial hypothesis; however, no significant improvement in outcome was seen. Similarly, in contrast to our hypothesis, complication rates did not significantly correlate with craniectomy size.