Activation of coagulation and fibrinolysis during cardiothoracic operations.
BACKGROUND
During open cardiac operations using cardiopulmonary bypass, there is activation of coagulation and fibrinolysis. We assessed the separate contributions of the surgical procedure itself and cardiopulmonary bypass to this, by studying sequential samples from patients undergoing routine open cardiac operations or thoracic operations without cardiopulmonary bypass.


METHODS
Activation of coagulation and the extent of fibrinolysis were measured from sequential samples obtained before the operation to 48 hours after the operation for 7 thoracic patients and 8 cardiac patients.


RESULTS
In the thoracic group operation length was shorter (p = 0.002), and there was no significant increase in thrombin-antithrombin III complexes or D-dimers until 24 hours postoperatively. In contrast, there was a highly significant increase in thrombin-antithrombin III complexes (p = 0.0043) and D-dimer levels (p = 0.009) during cardiopulmonary bypass. The increase in fibrinolytic activity was caused by an increase in tissue plasminogen activator (p = 0.013). At 48 hours postoperatively, the cardiac patients had a more hypercoagulable state than thoracic patients with significantly higher levels of thrombin-antithrombin III complexes (p = 0.041) and plasminogen activator inhibitor-1 activity (p = 0.0033).


CONCLUSIONS
This study suggests the major activation of coagulation and fibrinolysis seen during cardiac operations is caused by the use of cardiopulmonary bypass.
Hunt
B J
BJ
Department of Cardiothoracic Surgery, Imperial College School of Medicine at The National Heart and Lung Institute, Harefield Hospital, Middlesex, United Kingdom.
Parratt
R N
RN
Segal
H C
HC
Sheikh
S
S
Kallis
P
P
Yacoub
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000990:Antithrombin III / Q000032:analysis; D001777:Blood Coagulation / Q000502:physiology*; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis; D005342:Fibrinolysis / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010447:Peptide Hydrolases / Q000032:analysis; D010958:Plasminogen / Q000032:analysis; D019616:Thoracic Surgical Procedures; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000032:analysis; D014568:Urokinase-Type Plasminogen Activator / Q000097:blood
D005338:Fibrin Fibrinogen Degradation Products; C046193:antithrombin III-protease complex; C036309:fibrin fragment D; D000990:Antithrombin III; D010958:Plasminogen; D010447:Peptide Hydrolases; D010959:Tissue Plasminogen Activator; D014568:Urokinase-Type Plasminogen Activator