Comparative Analysis of Prothrombin Time and Activated Partial Thromboplastin Time in Cord blood and Maternal Venous Blood Samples.

Abstract

Introduction: The umbilical cord blood is known to contain potentially lifesaving cells called stem cells that are capable of self-renewal and differentiation offering therapeutic benefits for patients worldwide. The Activated Partial Thromboplastin Time (APTT), Prothrombin Time (PT) and International Normalized Ratio (INR) tests are used clinically to assess the integrity of the intrinsic, extrinsic and common pathways as well as monitor anticoagulant therapy and diagnose coagulation disorder. The difference in the level of APTT, PT and INR in cord blood and venous blood are yet to be accessed thus this study aimed to determine the difference between these parameters in cord blood and venous blood samples from mothers.

Materials and Methods: The study utilized eighty (80) blood samples comprising of 40 cord blood obtained directly from the umbilical cord immediately after delivery and 40 venous blood obtained from same pregnant women before delivery. 3ml of blood each were obtained aseptically from the vein and umbilical cord using a syringe and immediately dispensed into sample containing 333mls of tri-sodium citrate anticoagulant with proper mixing and centrifugation to obtain platelet poor plasma for analysis. The APTT, PT and INR values were analyzed and calculated manually using the spectrum reagent test kit following manufacturers instructions. The data obtained were analysed using Graph-Pad Prism version 8. Descriptive Analysis were done using Mean and Standard Deviation and p-value was set at p<0.05.

Results: The value of APTT, PT and INR was 30.5 ± 9.5s, 14.6 ± 2.9s and 1.18 ± 0.41 respectively for cord blood samples and 38.6 ± 9.9s, 17.8 ± 2.3s, 1.39 ± 0.49 for venous blood samples respectively. A comparison of the values of APTT, PT and INR between cord blood and venous blood samples showed that APTT, PT and INR were higher in venous blood samples compared to cord blood samples  (p=0.0004, p=0.0047, p=0.0142) respectively.  The reference ranges for APTT, PT and INR for cord blood was established in this study to be within 27–34 seconds, 14–16 seconds and 1.1–1.3 respectively and found to be within already established normal reference ranges.

Conclusion: APTT, PT and INR values are higher in venous blood compared to cord blood samples. APTT, PT and INR are found to be within normal reference range in cord blood samples. The elevated APTT, PT and INR in venous blood is an indication that during parturition, bleeding is inevitable and as such APTT, PT and INR  baseline values be accessed and incorporated as an integral part of routine antenatal tests for proper management of spontaneous or excessive bleeding complications during delivery.