Douglas County ambulances are no longer carrying the synthetic blood substitute, Polyheme.

The national trial that involved Douglas, Wyandotte and Leavenworth counties is complete, University of Kansas Hospital and Medical Center officials said today.

Area ambulances first stocked up on the synthetic blood manufactured by Northfield Laboratories in January as part of a clinical trial to evaluate the product’s safety and efficacy for critically injured and bleeding patients. The study involved 720 patients nationwide.

The study compared the survival rate of patients receiving PolyHeme to that of patients who receive the current standard of care, which is saline solution followed, in the hospital, by donated blood, when needed.

In a released statement, Michael Moncure, the principal investigator, said study protocols prohibit The University of Kansas Hospital and Medical Center from releasing any numbers of enrollees locally.