Abstract T P219: A Novel Method for Measuring Oxidative Stress in Patients with Stroke Symptoms

Abstract

Introduction: A novel device was developed to measure oxidation reduction potential (ORP), which is the balance of oxidants and reductants, providing a direct measure of oxidative stress. Our purpose was to measure ORP in patients admitted with stroke symptoms. Methods: This prospective observational study included patients admitted to our Primary Stroke Center from 1/2010-12/2012; children ≤18 and transfers were excluded. We examined ORP’s association with stroke type, demographics (age, gender, race), NIHSS, thrombolytic therapy, and outcomes (in-hospital mortality, mRS, LOS, readmission) using Pearson correlation, generalized linear models, chi-square and student’s t-tests. Blinded operators tested plasma samples in duplicate for static ORP (resting ORP, mV), where greater values indicate more oxidative stress, as well as Capacity (antioxidant reserve, uC). Capacity was inverse-transformed (icORP), where greater values indicate less reserves. Results: There were 101 patients including 52 ischemic strokes, 10 hemorrhagic strokes, 19 TIAs, and 20 mimics. Six patients died (6%); arrival ORP was significantly lower in patients who died than who survived (sORP: 137.2 vs 163.9, p = 0.004; icORP: 2.7 vs. 4.5, p = 0.02); the change in ORP between day 2 and arrival (ΔORP) was significantly greater in patients who died (sORP: 26.3 vs 5.4, p = 0.002; icORP: 1.5 vs. 0.0, p = 0.004). Arrival ORP was lowest in patients with severe stroke, while ΔORP was greatest in these patients (table 1), independent of thrombolytic therapy (interaction p =0.36). Arrival ORP was positively correlated with LOS (p = 0.003). Conclusions: These results demonstrate the ability of ORP to identify oxidative stress and amount of antioxidant reserves in a stroke population. We propose ORP monitoring as a potentially useful tool in evaluation of acute stroke patients.