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Cardiopulmonary bypass parameters and hemostatic response to cardiopulmonary bypass in infants versus children
Michael J Eisses1, Wayne L Chandler
1Department of Anesthesiology and Pain Medicine, University of Washington School of Medicine, Seattle, WA, USA. michael.eisses@seattlechildrens.org
Insights
Infants undergoing cardiac surgery with cardiopulmonary bypass (CPB) experience greater blood loss and platelet drops than older children. Infants showed lower active tissue plasminogen activator (tPA) and higher plasminogen activator inhibitor type 1 (PAI-1) during CPB.
Area of Science:
- Pediatric Cardiac Surgery
- Hemostasis and Thrombosis
- Cardiopulmonary Bypass
Background:
- Infants undergoing cardiac surgery with cardiopulmonary bypass (CPB) have proportionally higher blood loss than older children.
- Understanding differences in hemostatic activation is crucial for managing blood loss in pediatric cardiac surgery.
Purpose of the Study:
- To compare hemostatic activation between infants and older children during cardiac surgery with CPB.
- To identify factors contributing to increased blood loss in infants.
Main Methods:
- Observational study conducted at a university-affiliated children's hospital.
- Evaluated 28 children (18 infants <1 year, 10 children >1 year) undergoing cardiac surgery with CPB.
- Measured markers of coagulation and fibrinolysis at 9 time points before, during, and after CPB.
Main Results:
- Infants exhibited greater chest tube output, longer CPB times, and a larger drop in platelet counts compared to older children.
- Infants had lower active tissue plasminogen activator (tPA) and higher active plasminogen activator inhibitor type 1 (PAI-1) during CPB.
- Thrombin-antithrombin complex levels were lower in infants during CPB, while D-dimer and prothrombin activation peptide (F1.2) levels showed similar patterns in both groups.
Conclusions:
- Infants undergoing CPB show distinct hemostatic profiles, including greater blood loss, platelet reduction, lower active tPA, and higher active PAI-1 compared to older children.
- Cumulative thrombin generation post-CPB, indicated by F1.2 levels, correlated with early blood loss.
Objective:
Because infants have relatively more blood loss (mL/kg) than older children during cardiac surgery involving cardiopulmonary bypass (CPB), the authors compared hemostatic activation between infants and older children undergoing cardiac surgery.
Design:
Observational study.
Setting:
University-affiliated children's hospital.
Participants:
Twenty-eight children (18 infants <1 year and 10 children >1 year) undergoing cardiac surgery with CPB.
Interventions:
None.
Measurements And Main Results:
Markers of coagulation and fibrinolysis were evaluated at 9 sample points before, during, and after CPB in the 28 children. Infants had greater chest tube output, longer CPB times, and a larger drop in platelet counts during CPB than children. Active tissue plasminogen activator (tPA) increased during CPB in both groups, with infants showing lower levels than children (p < 0.001). In both groups, active plasminogen activator inhibitor type 1 (PAI-1) first decreased during CPB and then increased above baseline postoperatively. Infants had higher PAI-1 than children near the end of CPB (p = 0.01). Thrombin-antithrombin complex levels increased during and after CPB, with infants showing lower levels only during CPB (p = 0.01). D-dimer and prothrombin activation peptide (F1.2) levels increased in a similar pattern for both groups during and after CPB. The length of aortic cross-clamp time and the level of F1.2 after protamine administration correlated significantly and independently with 12-hour chest tube output.
Conclusions:
Compared with children, infants had greater blood loss (mL/kg), greater drop in platelets during CPB, lower active tPA, and higher active PAI-1. Cumulative thrombin generation after CPB, indicated by F1.2 levels, correlated with early blood loss.
