High blood viscosity in acute ischemic stroke

Abstract

AbstractBackground:Changes in blood viscosity can influence the shear stress level at the vessel wall. However, there is limited evidence to date regarding the role of high blood viscosity in acute thrombogenic events. We aimed to investigate the effect of blood viscosity on stroke occurrence and the clinical utility of blood viscosity measurements obtained immediately upon hospital arrival.Methods:Patients with suspected stroke visiting the hospital within 24 h of the last known well time were enrolled. Point-of-care testing was used to obtain blood viscosity measurements before intravenous fluid infusion. Blood viscosity was measured as the reactive torque generated at three different oscillatory frequencies (1, 5, and 10Hz). Blood viscosity results were compared among patients with stroke mimics, ischemic stroke, and hemorrhagic stroke.Results:Among 112 enrolled patients, blood viscosity measurements were accomplished within 2.4 ± 1.3 min of vessel puncture. At an oscillatory frequency of 10Hz, blood viscosity differed significantly between the ischemic stroke (24.2 ± 4.9cP) and stroke mimic groups (17.8 ± 6.5cP, P < 0.001). This finding was consistent at different oscillatory frequencies (134.2 ± 46.3 vs. 102.4 ± 47.2 at 1Hzand 39.2 ± 11.5 vs. 30.4 ± 12.4 at 5Hz, Ps < 0.001), suggesting a relationship between decreases in viscosity and shear rate. Among patients with ischemic, blood viscosity values were lower (16.4 ± 3.3) in those who had received intravenous fluid before blood sampling than in those who had not. The area under the receiver operating curve for differentiating cases of stroke from stroke mimic was 0.79 (95% confidence interval, 0.69 – 0.88).Conclusion:Patients with ischemic stroke exhibit increases in whole blood viscosity when admitted within 24 h of last known well time, suggesting that blood viscosity measurements can aid in differentiating ischemic stroke from other diseases.