COAGULATION STUDIES IN VERY-LOW-BIRTH-WEIGHT INFANTS

Reference values for coagulation studies of premature infants (24 to 2 9 weeks' gestational age) are needed for the management of hemostatic disorders in the precariously ill infant. We collected data on the ver y low-birthweight infants admitted to our intensive care nursery who m et criteria over a 4-year period to determine prothrombin time, activa ted partial thromboplastin time, and fibrinogen levels in this group. Fifty-two infants had a mean prothrombin time of 14.5 seconds, a mean activated partial thromboplastin time of 69.5 seconds, and a mean fibr inogen level of 1.35 g/L. Converting values to ratios of adult control values facilitated direct comparison of results to published referenc e ranges. Coagulation studies may vary over a broad range of prematuri ty, and normal ranges are needed for prospective, randomized protocols designed to prevent the complications of abnormal coagulation functio n.