Hemostatic consequences of a non-fresh or reconstituted whole blood small volume cardiopulmonary bypass prime in neonates and infants.

OBJECTIVES: Despite aggressive measures to miniaturize the cardiopulmonary bypass (CPB) circuit in neonates and infants, the CPB prime volume is often at least as large as the patients' blood volume. We conducted an observational study to characterize the hemostatic consequences of a CPB prime consisting of either non-fresh or reconstituted whole blood.

METHODS: Hematocrit, fibrinogen, platelet count, plasminogen, anti-thrombin III (AT-III), and factors (F) II, V, VII, IX, and X of 30 neonates and infants undergoing cardiac surgery with CPB utilizing either a non-fresh or reconstituted whole blood prime were prospectively evaluated at eight time points. Following protamine administration, microvascular bleeding was treated by protocol.

RESULTS: The hemostatic composition of the CPB prime was the same following the use of either non-fresh or reconstituted whole blood. The CPB prime platelet count (mean +/- SD) was 5.87 +/- 2.84 x 10(3) microl(-1) when compared to a preoperative platelet count of 298 +/- 142 x 10(3) microl(-1) (P < 0.0001). Twenty patients received 17.3 +/- 9.2 ml x kg(-1) (0.86 +/- 0.46 units x kg(-1)) of platelets with significant improvement in platelet count. Nine patients received 16.7 +/- 13.4 ml x kg(-1) (0.84 +/- 0.67 units x kg(-1)) of cryoprecipitate with significant improvements in FVIII and fibrinogen.

CONCLUSIONS: Non-fresh or reconstituted whole blood as a component of a small volume CPB prime in neonates and infants induces clinically significant dilutional thrombocytopenia in conjunction with less significant reductions in fibrinogen, FII, FV, FVII, FVIII, FIX, FX, plasminogen, and AT-III.