PMID- 34231501
OWN - NLM
STAT- MEDLINE
DCOM- 20210714
LR  - 20230924
IS  - 1473-5733 (Electronic)
IS  - 0957-5235 (Linking)
VI  - 32
IP  - 5
DP  - 2021 Jul 1
TI  - Effect of unfractionated heparin and low molecular weight heparin on the clotting 
      of platelet-reduced whole blood: an in-vitro study utilizing thromboelastography.
PG  - 305-311
LID - 10.1097/MBC.0000000000001023 [doi]
AB  - Treatment of venous thromboembolism with concomitant thrombocytopenia is 
      challenging. The platelet threshold for safe administration of anticoagulants is 
      under debate, with minimum platelet count of 50 x 109/l being recommended as the 
      safe cutoff. However, some evidence suggests administration of anticoagulants may 
      still be safe at platelet levels of 30 x 109/l. Therefore, we developed an 
      in-vitro thromboelastography (TEG) study to examine the effect of therapeutic or 
      prophylactic levels of unfractionated heparin (UFH) and low molecular weight 
      heparin (LMWH) on the clotting profile of platelet-reduced whole blood. Using 
      magnetic bead-based antibody chromatography, platelets were removed to achieve 
      platelet-depleted blood (<10 x 109/l of platelets). Platelet-depleted blood was 
      then mixed with whole blood to produce blood samples with platelet counts of 
      30 x 109, 50 x 109 and 150 x 109/l. These blood samples were incubated with 
      therapeutic or prophylactic levels of UFH or LMWH in disposable TEG cups. 
      Clotting was initiated with 10 mmol/l calcium and optimized tissue factor levels 
      for each anticoagulant used (2.25 pmol/l for UFH and 2.05 pmol/l for LMWH). 
      Clotting was monitored by TEG at 37  degrees C for 180 min. The following TEG parameters 
      were evaluated: R (time to clot), maximum amplitude (strength of clot) and area 
      under the curve in 15 min (overall speed and strength of the clot at 15 min of 
      clotting). No statistically significant differences were observed between 
      platelet counts of 30 x 109 and 50 x 109/l for R, maximum amplitude or area under 
      the curve in 15 min for most of the therapeutic and prophylactic doses of UFH and 
      LMWH tested in this study. Use of anticoagulants compromised all of the TEG 
      parameters relative to a normal platelet count of 150 x 109/l, in a dose 
      dependent manner. The current study demonstrates that in-vitro clotting is 
      impaired with use and increasing doses of anticoagulants. Despite this 
      observation, we did not observe a significant difference in clotting between 
      platelet levels of 30 x 109 and 50 x 109/l. Overall, this work provides further 
      insight in the debated use of anticoagulants in patients with venous 
      thromboembolism and concomitant thrombocytopenia, and provides support for 
      possible use of anticoagulants at lower platelet thresholds.
CI  - Copyright (c) 2021 Wolters Kluwer Health, Inc. All rights reserved.
FAU - Chung, Jason
AU  - Chung J
AD  - Thrombosis and Atherosclerosis Research Institute (TaARI), McMaster University, 
      Hamilton.
FAU - Stevic, Ivan
AU  - Stevic I
AD  - Department of Pathology and Laboratory Medicine, Western University, London, 
      Ontario.
FAU - Gantioqui, Jorell
AU  - Gantioqui J
AD  - Clinical Research Unit, Vancouver Coastal Health/University of British Columbia, 
      Vancouver, British Columbia.
FAU - Atkinson, Helen
AU  - Atkinson H
AD  - Thrombosis and Atherosclerosis Research Institute (TaARI), McMaster University, 
      Hamilton.
AD  - Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada.
FAU - Chan, Anthony K C
AU  - Chan AKC
AD  - Thrombosis and Atherosclerosis Research Institute (TaARI), McMaster University, 
      Hamilton.
AD  - Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada.
FAU - Chan, Howard H W
AU  - Chan HHW
AD  - Thrombosis and Atherosclerosis Research Institute (TaARI), McMaster University, 
      Hamilton.
LA  - eng
PT  - Journal Article
PL  - England
TA  - Blood Coagul Fibrinolysis
JT  - Blood coagulation & fibrinolysis : an international journal in haemostasis and 
      thrombosis
JID - 9102551
RN  - 0 (Anticoagulants)
RN  - 0 (Heparin, Low-Molecular-Weight)
RN  - 9005-49-6 (Heparin)
SB  - IM
MH  - Anticoagulants/*pharmacology
MH  - Blood Coagulation/*drug effects
MH  - *Blood Platelets/drug effects
MH  - Heparin/*pharmacology
MH  - Heparin, Low-Molecular-Weight/*pharmacology
MH  - Humans
MH  - Platelet Count
MH  - Thrombelastography
MH  - Thrombocytopenia/blood
MH  - Venous Thromboembolism/blood
EDAT- 2021/07/08 06:00
MHDA- 2021/07/15 06:00
CRDT- 2021/07/07 08:45
PHST- 2021/07/07 08:45 [entrez]
PHST- 2021/07/08 06:00 [pubmed]
PHST- 2021/07/15 06:00 [medline]
AID - 00001721-202107000-00001 [pii]
AID - 10.1097/MBC.0000000000001023 [doi]
PST - ppublish
SO  - Blood Coagul Fibrinolysis. 2021 Jul 1;32(5):305-311. doi: 
      10.1097/MBC.0000000000001023.