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

Introduction: Prognostication after subarachnoid hemorrhage (SAH) is essential to guide clinical management and improve patient care.

Objective: To investigate whether decay rates of cerebrospinal fluid (CSF) red blood cells (RBC) and total protein (TP) after SAH predict functional outcome at 3 months.

Methods: Patients 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.

Results: A 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/μL 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).

Conclusions: Decay rates of CSF RBC and TP after SAH are associated with functional outcomes.