Effect of Ambient Temperature and Prolonged Storage on Prothrombin Time and Activated Partial Thromboplastin Time During Summers in Pakistan

Abstract

Objective: The current study was carried out to determine the effect of sample storage duration on PT and aPTT, when samples are stored at ambient temperatures during summers in Lahore, Pakistan. 

Study Design: Cross sectional study

Place and Duration of Study: This study was conducted at the Hematology department of King Edward Medical University in June 2021.

Materials and Methods: Eighty blood samples collected in 3.8% sodium citrate vial and PT and aPTT was   performed manually at 0, 4, 8, 12 and 24 hours. First test was performed immediately after sample collection (0 hours) which was taken as reference. Paired sample t-test was used for comparison of PT and APTT at 4, 8, 12 and 24 hours with the value at 0 hours while a mean percentage difference of more than 10% from the baseline value was taken as clinically significant.

Results: Initially PT results did not show any clinically significant change until 24 hours and aPTT till 8 hours.

Conclusion: Samples for PT testing give acceptable results up to 8 hours post collection, and for aPTT testing up to 4 hours, when stored at ambient temperatures during summer seasons