Vitamin K coagulation status in surgical newborns and the risk of bleeding

The vitamin K coagulation status in surgical newborns, who may be at increased risk of developing hypocoagulability and hemorrhage, has not previously been studied. Therefore, we measured the combined activity of the plasma vitamin K-dependent coagulation factors (Thrombotest), total prothrombin, PIVKA II, plasma vitamin K1, fibrinogen, D-Dimer, and platelets in 49 newborns admitted to a neonatal surgical intensive care unit. All infants had significant pathology, and treatment involved surgery in all but two. Twenty-three infants (47%) underwent surgery on two or more occasions. Intravenous or oral antibiotics were used in all patients and many received more than one course. All infants had vitamin K1 prophylaxis at birth. At day 0 (date of birth), the mean Thrombotest and total prothrombin levels were 51% (range, 20% to 100%) and 40% (range, 24% to 59%), respectively. Coagulation activity decreased on day 1 ( P >.1) and was followed by a graduate increase in clotting activity, reaching normal adult levels (>60%) at day 5 for Thombotest and day 24 for total prothrombin. Only three infants had a Thrombotest less than 20%. PIVKA II was detected in 20 cases (41%). However, levels were within normal limits (