Jelani et al. J Biomed & App Sci FUD (2025) 4:1
Keywords: Clot contact, serum, temperature, Sokoto
2025-10-01 DOI: Jelani et al., JOBASFUD_2024_3_2_007
Abstract Background: Clot contact time is an optimal time interval between sample collection and separation of serum from the clot. Delays in serum separation from red cells are often unavoidable in laboratory settings for various reasons. Objectives: To evaluate whether the stability of renal function parameters are affected in serum kept in contact with clot over time. Methods: This cross-sectional study involved fifty healthy adults enrolled to establish maximum acceptable delay time for renal function parameters. Venous blood specimens were collected and aliquoted into plain plastic tubes. The first clotted samples were centrifuged and the harvested sera serve as baseline sample (0 hr). The 2nd, 3rd, and 4th clotted samples were centrifuged after 4 hr, 8 hr and 12 hr respectively at room temperature for renal function tests. Data analysis was with Repeated Measures ANOVA Tool in Graph Pad InStat Software. Results: Serum kept in contact with clot for 4 hours at room temperature significantly increased in sodium and creatinine values. Increase in urea and potassium with decrease in chloride ion within 4 hours was also observed compared to 0 hour. Bicarbonate concentration increased significantly within 8 hours compared to the base line value and decreases after 8 hours. Conclusion: This study suggests that for optimal clinical utility, serum specimens should be separated immediately from clots for renal function test. However, the acceptable delay period for potassium, chloride, bicarbonate and urea is within 4 hours at room temperature.