Mediastinal Bleeding Causes:
**Coagulopathy 2° to CPB:
- hemodilution from crystalloid prime
- extracorporeal circuit triggers fibrinolysis
- heparinization causes platelet dysfunction
- depletion of coagulation factors and platelets from use of cell saving devices.
**Sugical Bleeding
- anastomotic sites
- sidebranches of arterial or venous conduits
- substernal soft tissues, sternal sutures sites, bone marrow, periosteum
- raw surfaces caused by previous surgery, pericarditis or radiation therapy
** anticoagulant effect related to heparin (residual or rebound)
** thrombocytopenia
** fibrinolysis
Mediastinal rexploration indications:
- Cardiac tamponade
- acute onset of rapid bleeding: >300 - 400 ml/hr, >200 ml/hr x3- 4 hrs