Assessment of coagulation parameters and D dimer levels among neonates in Lagos, Nigeria – An attempt at establishing normal values for clinical decision making

Résumé

Abstract: Background: The management of newborn haemostatic defects pose challenges due to lack of reference values. This study aimed to assess coagulation parameters among newborns with attempt to define normal values, and any significant  biologic or pathologic variables.
Methods: A cross-sectional study involving 96 singleton newborns (regardless of term) from selected hospitals in Lagos.  Umbilical cord blood samples were collected and analyzed for coagulation profile parameters: prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin time (TT), and D-dimer. Assay results were described as mean ± SD, median, range and percentiles. Categorical data were described as frequency and proportions.
Results: Mean gestational age was 37.96 ± 2.75 weeks, and mean birth weight was 3.29 ± 0.49 kg. The mean±SD values for coagulation profile parameters were: PT: 22.09±7.58 seconds, aPTT: 60.86±17.99 seconds, TT: 11.21±3.56 seconds, and D-dimer:
266.59±144.25 ng/ml FEU. Determined 2.5 to 97.5 percentiles for umbilical cord blood coagulation profile parameters were: PT: 6.93- 37.25 seconds, aPTT: 24.88-96.84 seconds, TT: 4.09-18.33 seconds, and D-dimer: <555.09 ng/ml FEU. No association was  found between sex, gestational age, birth weight, APGAR score, and coagulation studies.
Conclusion: This study provides the coagulation parameters among newborns using umbilical cord blood based on identified clinical and biologic characteristics of study participants. The findings highlight the need for more expansive research into age-, sex-, geographical location-specific reference ranges for coagulation parameters in newborns, compared with other populations. The results will aid in the interpretation of coagulation tests in neonates, facilitating the diagnosis and management of coagulation disorders.