The relationship between hematocrit and bleeding time in very low birth weight infants during the first week of life.

OBJECTIVES: The bleeding time is a measurement of platelet and capillary interaction following a small standardized cutaneous incision. In adults, anemia causes a prolongation of the bleeding time, and we hypothesized that the same would be true in very low birth weight (VLBW) infants during their first week of life. STUDY DESIGN: Template bleeding times, using the Surgicutt Newborn device, were performed on 20 VLBW weight infants <or=7 days old, before, and again following a clinically ordered erythrocyte transfusion. RESULTS: Neonates who had pretransfusion hematocrits <or=0.28 l/l had longer bleeding times, which fell 164+/-25 seconds (mean+/-SD; p<0.0001) following transfusion. Patients with pretransfusion hematocrits >0.28 l/l had no significant reduction in bleeding time following transfusion. CONCLUSIONS: In VLBW infants, during their first week of life (the time when their risk of intraventricular hemorrhage is greatest), a low hematocrit is associated with a significant prolongation in the bleeding time.