Emergency department and transport predictors of neurological deterioration in patients with spontaneous intracranial hemorrhage.

Background: Patients with spontaneous intracranial hemorrhage (sICH) and intracranial hypertension are associated with poor outcomes. Blood pressure variability (BPV) and neurological deterioration (ND) are known factors associated with sICH outcomes, but the relationship between BPV and ND in the hyperacute phase remains poorly described. We hypothesized that BPV is associated with ND during patients' initial emergency department (ED) stay and during interhospital transport (IHT) to a tertiary care center.

Methods: A retrospective study of adult patients with sICH was performed. Patients who were transferred from an ED to a tertiary care center between 01/01/2011 and 09/30/2015 and underwent external ventricular drainage were eligible. The outcome was ND at any time before arrival at a tertiary care center. Classification and Regression Tree (CART) analysis, a machine learning algorithm, was used to assign "relative variable importance" (RVI) for important predictive clinical factors.

Results: 153 eligible patients were analyzed. Sixty-five (42%) patients developed ND. Maximum ED systolic blood pressure (ED SBP) was most predictive of sICH patients developing ND (RVI = 100%). Other important factors for ND included standard deviation in SBP (SBP) during ED stay and IHT, with RVI of 43% and 20%, respectively.

Conclusion: ED SBP was the strongest predictive factor of ND, while other BPV components were also significant. Our study found evidence that BPV should be prioritized as it may also increase the risk of ND among patients with sICH who required external ventricular drain placement. Future studies should examine whether fluctuations in BP in an ED or IHT setting are associated with increased risk of worsening outcomes.