Cerebrospinal Fluid Catecholamine Levels as Predictors of Outcome in Subarachnoid Hemorrhage

Abstract
Objective: Subarachnoid hemorrhage (SAH) is associated with marked sympathetic activation at the time of ictus. The purpose of this study is to determine whether early central catecholamine levels measured from cerebrospinal fluid (CSF) relate to outcome in patients with SAH. Methods: Observational study of consecutive SAH grade 3–5 patients who underwent ventriculostomy placement, but did not undergo open craniotomy for aneurysm obliteration. CSF samples were obtained during the first 48 h following symptom onset and assayed for catecholamine levels. Statistical analyses were performed to determine whether the levels predicted mortality by day 15 or mortality/disability by day 30. Results: For the 102 patients included, mean age was 58, and 73% were female – 21% experienced day-15 mortality, and 32% experienced mortality/disability by day 30. Early mortality was related to Hunt-Hess (H/H) grade (p < 0.001), neurogenic cardiomyopathy (NC) (p = 0.003), cerebral infarction (p = 0.001), elevated intracranial pressure (ICP) (p = 0.029), epinephrine (EPI) level (p = 0.002) and norepinephrine/3,4-dihydroxyphenylglycol (NE/DHPG) ratio (p = 0.003). Mortality/disability was related to H/H grade (p < 0.001), NC (p = 0.018), infarction (p < 0.001), elevated ICP (p = 0.002), EPI (p = 0.004) and NE/DHPG (p = 0.014). Logistic regression identified age [OR 1.09 (95% CI 1.01–1.17)], H/H grade [9.52 (1.19–77)], infarction [10.87 (1.22–100)], ICP elevation [32.26 (2–500)], EPI [1.06 (1.01–1.10)], and (inversely) DHPG [0.99 (0.99–1.00)] as independent predictors of early mortality. For mortality/disability, H/H grade [OR 21.74 (95% CI 5.62–83)], ICP elevation [18.52 (1.93–166)], and EPI [1.05 (1.02–1.09)] emerged as independent predictors. Proportional-hazards analysis revealed age [HR 1.041 (95% CI 1.003–1.08)], H/H grade [6.9 (1.54–31.25)], NC [4.31 (1.5–12.35)], and EPI [1.032 (1.009–1.054)] independently predicted early mortality. Conclusions: CSF catecholamine levels are elevated in SAH patients who experience early mortality or disability. EPI may potentially serve as useful index of outcome in this population of patients with SAH.