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Published on: March 19, 2016
Clotting functional stability of withdrawing blood in storage for acute normovolemic hemodilution: a pilot study
Hirotaka Kinoshita1, Junichi Saito2, Kishiko Nakai1
1Department of Anesthesiology, Hirosaki University Graduate School of Medicine, Zaifu-cho 5, Hirosaki, 036-8562, Japan.
Purpose:
This study was conducted to time-course changes of clotting function of withdrawing blood for acute normovolemic hemodilution (ANH).
Methods:
Twelve enrolled patients who underwent ANH from August, 2018 to January, 2019. Blood was withdrawn into blood collection pack and shaken at 60-80 rpm for 24 h in room temperature. Clot formation was evaluated using rotational thromboelastometry (ROTEM™) just after blood withdrawal (control) and 4, 8, 12 and 24 h after blood withdrawal. We compared with the control value and each value of extrinsically-activated test with tissue factor (EXTEM), intrinsically-activated test using ellagic acid (INTEM) and fibrin-based extrinsically activated test with tissue factor (FIBTEM).
Results:
Maximum clot firmness (MCF) of FIBTEM did not change significantly. MCF of EXTEM was significantly decreased time-dependent manner but all MCF of EXTEM were within a normal range. Maximum percent change in MCF of EXTEM was 12.4% [95% confidence interval (CI): 9.0-15.8%]. The difference in the maximum clot elasticity (MCE) between EXTEM and FIBTEM (MCEEXTEM-MCEFIBTEM) was significantly decrease from 8 h after blood withdrawal. Maximum percent change in MCEEXTEM-MCEFIBTEM was 30.2% (95% CI:17.6-42.9%) at 24 h after blood withdrawal.
Conclusion:
Even though the MCE significantly decreased in a time-dependent manner, MCF of FIBTEM and EXTEM was normal up to 24 h storage. The blood of ANH can use for the purpose of hemostasis at least 8 h stored at room temperature after blood withdrawal. Future studies are needed to elucidate the clinical impact on the patient after delayed transfusion of ANH blood with regard to patient's hemostasis.
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