Abstract
BACKGROUND: Whole blood viscosity (WBV) determines wall shear stress, representing dynamic force and contributing to aneurysmal remodeling. We hypothesized that administering balanced crystalloid (Group-C) or hydroxyethyl starch (HES) 130/0.4 (Group-HES) for IV fluid management would have a different impact on high-shear WBV during the endovascular detachable coiling (EDC). METHODS: Thirty EDC patients randomly got HES (Group-HES, n = 15) or crystalloid (Group-C, n = 15) as the main IV fluid resuscitation during the procedure. The WBV at a shear rate of 300 sec(-)¹ of arterial blood samples (WBV₃₀₀), which depict WBV at a larger-sized artery, were determined and analyzed before and after the EDC procedure (Pre and Post). The changes in hematocrit (Hct) and arterial-to-inspired-fraction oxygen ratio (P/F-O₂ ratio) were determined as indices of the degrees of hemodilution and extravascular fluid shift, respectively. RESULTS: The median (25-75%) volume of infused crystalloid was 800 (700, 1,200) mL in Group-C and those of HES and crystalloid were 400 (150, 750) and of 500 (400, 600) mL in Group-HES, respectively. Pre-WBV₃₀₀ showed no significant inter-group difference. However, Post-WBV₃₀₀ in Group-HES was significantly lower than in Group-C (3.40 ± 0.33 vs. 3.95 ± 0.79 centipoise, P = 0.023). The Hct and P/F-O₂ ratios were comparable between the two groups. CONCLUSION: Our study showed that HES infusion provided significantly lower WBV than crystalloid infusion during the EDC procedure. Further study is warranted to determine whether the lower WBV after HES infusion would enhance clinical outcomes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02700607.