Faster Decay of Cerebrospinal Fluid Red Blood Cells and Total Protein Predict Good Functional Outcome After Subarachnoid Hemorrhage

IntroductionPrognostication after subarachnoid hemorrhage (SAH) is essential to guide clinical management and improve patient care. ObjectiveTo investigate whether decay rates of cerebrospinal fluid (CSF) red blood cells (RBC) and total protein (TP) after SAH predict functional outcome at 3 months. MethodsPatients with SAH treated at the Neurological Intensive Care Unit Innsbruck with a first CSF sample (CSFfirst) within 72 h after admission and at least one subsequent sample were eligible for inclusion. Decay rates of RBC and TP were measured between CSFfirst and each subsequent measurement (Weeks 1-3). Modified Rankin Scale scores at 3 months <= 2 were defined as good functional outcomes. ResultsA total of 97 patients with a median age of 61 years [25th; 75th percentile: 52;71] and a median Hunt and Hess score of 4 [3;5] were included. Daily RBC decay rates decreased over time, while daily TP decay rates were highest in Week 1, showed a nadir in Week 2, and increased again in Week 3. In multivariable analysis, higher RBC (adjusted odds ratio (adjOR): 1.13, 95% confidence interval (95% CI): 1.02-1.26, p = 0.025) and TP (adjOR: 1.01, 95% CI: 1.00-1.01, p = 0.031) decay rates at Week 3 predicted a good functional outcome at Month 3. RBC and TP decreasing below 1180 cells/mu L and 127.5 mg/dL, respectively, at Week 3 were associated with good functional outcome at Month 3 (adjOR: 11.04, 95% CI: 3.21-38.02, p < 0.001 and 6.03, 1.68-21.67, p = 0.006). ConclusionsDecay rates of CSF RBC and TP after SAH are associated with functional outcomes.