Table 3. Coagulation factors.

Variable	PP ( n  = 23)	PMP ( n  = 21)	p -Value
Average daily heparin rates (U/kg/h)	33 ± 15	21 ± 14	< 0.05
Min ACT (s)	179 ± 16	185 ± 20	0.28
Max ACT (s)	305 ± 40	299 ± 43	0.65
Morning platelet level (×1,000)	104 ± 25	99 ± 25	0.51

Abbreviations: ACT, activated clotting time; PMP, polymethylpentene; PP, polypropylene.

Note: Unfractioned heparin was initiated at an initial dose of 20 to 30 U/kg/h within 2 hours of initiation of ECMO or once ACTs drop below 380 seconds. ACTs were assessed every hour and heparin was titrated to maintain ACTs between 200 and 240 seconds. Platelet levels were assessed q8 to q12h.