Thromb Haemost 1997; 77(02): 270-277
DOI: 10.1055/s-0038-1655952
Original Article
Schattauer GmbH Stuttgart

Coagulation and Fibrinolytic Profile of Paediatric Patients Undergoing Cardiopulmonary Bypass

Anthony K C Chan
1   The Research Institute, McMaster University, Hamilton, Ontario, Canada
,
Michael Leaker
7   The Department of Paediatrics, McMaster University, Hamilton, Ontario, Canada
,
Frederick A Burrows
2   Department of Anaesthesia, McMaster University, Hamilton, Ontario, Canada
5   Department of Paediatrics, McMaster University, Hamilton, Ontario, Canada
,
William G Williams
3   Department of Cardiovascular Surgery, McMaster University, Hamilton, Ontario, Canada
,
Colleen E Gruenwald
6   Department of Cardiovascular Perfusion, The Hospital for Sick Children, Toronto, Canada
,
Linda Whyte
2   Department of Anaesthesia, McMaster University, Hamilton, Ontario, Canada
,
Margaret Adams
4   Department of Haematology/Oncology, McMaster University, Hamilton, Ontario, Canada
,
Lu Ann Brooker
7   The Department of Paediatrics, McMaster University, Hamilton, Ontario, Canada
,
Helen Adams
4   Department of Haematology/Oncology, McMaster University, Hamilton, Ontario, Canada
,
Lesley Mitchell
7   The Department of Paediatrics, McMaster University, Hamilton, Ontario, Canada
,
Maureen Andrew
4   Department of Haematology/Oncology, McMaster University, Hamilton, Ontario, Canada
7   The Department of Paediatrics, McMaster University, Hamilton, Ontario, Canada
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Weitere Informationen

Publikationsverlauf

Received 06. September 1995

Accepted after revision 17. Oktober 1996

Publikationsdatum:
10. Juli 2018 (online)

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Summary

The haemostatic system and the use of heparin during cardiopulmonary bypass (CPB) have been studied extensively in adults but not in children. Results from adult trials cannot be extrapolated to children because of age-dependent physiologic differences in haemostasis. We studied 22 consecutive paediatric patients who underwent CPB at The Hospital for Sick Children, Toronto. Fibrinogen, factors II, V, VII, VIII, IX, XI, XII, prekallikrein, protein C, protein S, antithrombin (AT), heparin cofactor II, α2-macroglobulin, plasminogen, α2-antiplas- min, tissue plasminogen activator (tPA), plasminogen activator inhibitor, thrombin-AT complexes (TAT), D-dimer, heparin (by both anti-factor Xa assay and protamine titration) and activated clotting time (ACT) were assayed perioperatively. The timing of the sampling was: pre heparin, post heparin, after initiation of CPB, during hypothermia, post hypothermia, post protamine reversal and 24 h post CPB. Plasma concentrations of all haemostatic proteins decreased by an average of 56% immediately following the initiation of CPB due to haemodilution. During CPB, the majority of procoagulants, inhibitors and some components of the fibrinolytic system (plasminogen, α2AP) remained stable. However, plasma concentrations of TAT and D-dimers increased during CPB showing that significant activation of the coagulation and fibrinolytic systems occurred. Mechanisms responsible for the activation of haemostasis are likely complex. However, low plasma concentrations of heparin (<2.0 units/ml in 45% of patients) during CPB were likely a major contributing etiology. ACT values showed a poor correlation (r = 0.38) with heparin concentrations likely due to concurrent haemodilution of haemostatic factors, activation of haemostatic system, hypothermia and activation of platelets. In conclusion, CPB in paediatric patients causes global decreases of components of the coagulation and fibrinolytic systems, primarily by haemodilution and secondarily by consumption.