341 Timing of Cranioplasty and CSF Diversion After Decompressive Hemicraniectomy Impacts Clinical Outcomes

INTRODUCTION: Decompressive craniectomy (DC) is a common neurosurgical procedure used to reduce elevated intracranial pressure. Many patients subsequently require cranioplasty (CP) and/or ventriculoperitoneal shunt (VPS) placement. METHODS: This multi-centered retrospective study included 237 adult patients who underwent DC between 2016-2022. Statistical analyses examined associations between procedure timing and outcomes, including shunt revision, readmission rate, LOS, and 6-month Glasgow Outcome Scale (GOS). RESULTS: A total of 237 patients that received DC (54% trauma, 31% stroke, 15% other / multiple indications) were included in our study. The median (IQR) age was 50 years (34-63) and 64% of patients were male. Multivariate regression analysis revealed significant associations between procedure timing and LOS. Patients receiving CP before VPS had the longest average LOS (p=0.008), followed by concurrent CP/VPS (p<0.001), and VPS before CP (p=0.003). However, timing did not impact 6-month GOS, hospital readmission, subdural hygroma, or shunt revision rates at 6 months. Patients receiving synthetic cranioplasty materials had significantly longer LOS compared to autologous bone flaps (p=0.04). Approximately 10% of patients experienced postoperative infection or ventriculitis, with no significant difference between timing groups. CONCLUSIONS: Data from this large multi-centered study revealed that the timing sequence between CP and VPS did not have a significant effect on functional outcomes at 6-months. Additionally, patients who underwent VPS before or concurrently with CP minimized hospital LOS compared to CP before VPS.