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Published on: December 31, 2015
Coagulation studies in very low-birthweight infants
1Kansas University Children's Center, Department of Pediatrics, University of Kansas Medical Center, Kansas City.
Insights
Establishing reference ranges for coagulation studies in premature infants (24-29 weeks gestational age) is crucial for managing bleeding disorders. This study provides vital prothrombin time, activated partial thromboplastin time, and fibrinogen data for very low-birthweight infants.
Area of Science:
- Neonatal Medicine
- Pediatric Hematology
- Clinical Pathology
Background:
- Premature infants, especially those with very low birth weight, often experience hemostatic disorders.
- Accurate reference values for coagulation parameters in this population are essential for effective clinical management.
- Existing reference ranges may not adequately represent the unique physiological state of extremely premature neonates.
Purpose of the Study:
- To determine reference values for prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen levels in premature infants.
- To establish normal coagulation ranges for infants born between 24 and 29 weeks' gestational age.
- To facilitate comparison with adult reference ranges by converting infant values to ratios.
Main Methods:
- Prospective data collection over a 4-year period from very low-birthweight infants admitted to a neonatal intensive care nursery.
- Measurement of prothrombin time, activated partial thromboplastin time, and plasma fibrinogen levels.
- Calculation of ratios of infant coagulation values to adult control values.
Main Results:
- Fifty-two premature infants (24-29 weeks gestational age) were analyzed.
- Mean PT was 14.5 seconds, mean aPTT was 69.5 seconds, and mean fibrinogen level was 1.35 g/L.
- Ratio comparisons aided in standardizing results against established adult reference ranges.
Conclusions:
- The study provides essential reference values for coagulation parameters in extremely premature infants.
- These data are critical for the diagnosis and management of hemostatic disorders in this vulnerable patient group.
- Normal ranges are needed for developing evidence-based protocols to prevent complications of abnormal coagulation in preterm neonates.
Abstract:
Reference values for coagulation studies of premature infants (24 to 29 weeks' gestational age) are needed for the management of hemostatic disorders in the precariously ill infant. We collected data on the very low-birthweight infants admitted to our intensive care nursery who met criteria over a 4-year period to determine prothrombin time, activated 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 fibrinogen level of 1.35 g/L. Converting values to ratios of adult control values facilitated direct comparison of results to published reference ranges. Coagulation studies may vary over a broad range of prematurity, and normal ranges are needed for prospective, randomized protocols designed to prevent the complications of abnormal coagulation function.

