Abstract 1122‐000094: EVD Weaning Criteria Decreases VPS/ETV Placement and Hospital Stay in Subarachnoid Hemorrhage Patients

Abstract

Introduction : The Neurocritical Care Society encourages an external ventricular drain (EVD) wean “as quickly as is clinically feasible” but guidelines on achieving it are limited (1). This study aims to improve quality of care by sharing a protocol to initiate EVD weaning. These criteria were developed over 7 years and showed a reduction in ventriculoperitoneal shunt/endoscopic third ventriculostomy (VPS/ETV) placement and length of stay (LOS) at our institute compared to national averages. Methods : 151 subarachnoid hemorrhage (SAH) patients from January 2016 to January 2019 were analyzed. 60 aneurysmal SAH (aSAH) and 18 non‐aneurysmal nontraumatic SAH (naSAH) patients required EVD placement. A gradual EVD weaning protocol was initiated if patients met the following criteria: the reason for EVD placement has resolved or is resolving, quantity of CSF output must be <250mL over 24 hours, quality of CSF must be nonbloody, ICP must be within normal limits, and the patient must be neurologically stable. It was acceptable to wean when the patient had mild cerebral vasospasm, but not moderate to severe cerebral vasospasm. EVD weaning was performed by increasing drain height by 5 millimeters of mercury every 24 hours if criteria were met. Charts were reviewed for LOS and rate of VPS/ETV. Gender, age, race, wean failure incidence, infection rates, and SIADH/CSW rates were obtained. Results : Average LOS for aSAH patients with EVD at our institute was 20.35 days. Incidence of VPS/ETV was 11%. Chi‐square analysis was performed, and aSAH patients were found to have higher rates of VPS/ETV placement (p<0.001) and EVD wean failures (p<0.001) than naSAH patients. Conclusions : Our criteria to initiate EVD weaning provided a reduction in VPS/ETV placement among aSAH patients compared to national averages and provides a standardized approach to EVD management. aSAH patients at our institute had a lower incidence of VPS/ETV placement of 11% compared to 21% nationally (2). aSAH patients at our institute also had a lower LOS at 20.35 days compared to 21.5 days nationally (3).