PB0572 - Potency-adjusted bovine heparin exhibits similar anticoagulant effects as porcine heparin in whole blood clotting studies

Background: Bovine and porcine heparins were traditionally used for surgical and interventional anticoagulation; however, currently only porcine heparin is used in the US. The anticoagulant potency of bovine heparin is 30 – 40% lower than porcine heparin as measured by using USP assays.

Aims: We compared the activated clotting times of bovine (Adeste) heparin against porcine (Medefil) heparin with a saline control for gravimetric and potency-adjusted concentrations.

Methods: Informed consent was obtained from participants under an Institutional protocol. Blood samples drawn from each participant over a period of weeks were supplemented with each heparin at a concentration of 10 µg/mL with a final volume of 2 mL for gravimetric samples. Potency-adjusted heparins were analyzed at 1 U/mL. For the control, 200 µL of normal saline was used. Hemochron automated coagulation timers measured activated clotting times.

Results: Brown-Forsythe and Welch’s ANOVA tests revealed a significant difference between means of gravimetric samples (p < 0.0001 for both). Dunnett’s T3 test of multiple comparisons subsequently showed a significant difference for all pairs of mean group values (p < 0.0001 for all pairwise comparisons, figure 1). For potency-adjusted samples, there was no significant difference between bovine and porcine heparins (p = 0.83, figure 2). The mean activated clotting times of saline, bovine, and porcine heparins were 138 ± 9 seconds, 274 ± 35 seconds, and 368 ± 63 seconds for the gravimetric samples and 132 ± 7 seconds, 272 ± 10 seconds, and 275 ± 10 seconds for potency-adjusted samples, respectively (time ± SD).

Conclusion(s): Gravimetric samples of porcine and bovine heparins showed a significant difference compared to the control, as expected. Porcine heparin was observed to possess a higher mean activated clotting time than bovine. Potency-adjusted porcine and bovine heparins showed no significant difference in activated clotting time. Potency-adjusted bovine heparins may be interchangeable with porcine heparin.