ECMO Data Points to Antithrombin Plus Heparin

ECMO can provide life support for adults during cardiopulmonary surgery when other interventions fail. The heart and lungs may need outside help, and the blood still has to be handled with care. Clotting is a major risk, which is why unfractionated heparin is often used during ECMO.

The hard part is that unfractionated heparin may not work well in antithrombin deficiency. Some patients also develop heparin resistance. That can make treatment choices less clear, because the usual blood thinner may not give enough protection.

Researchers compared two treatment paths in adult ECMO patients. One path used antithrombin concentrate plus unfractionated heparin. The other used bivalirudin. The research was retrospective and used the TriNetX database from 2014 to 2023 and the Premier Healthcare Database from 2018 to 2021. Patients had to receive one of these treatments within three days of ECMO start. People who had cardiopulmonary bypass or coronary artery bypass grafting during the same ECMO hospital stay were not included. Propensity score matching was used to make the groups more comparable.

The teams tracked thrombotic events, bleeding events, heparin-induced thrombocytopenia, hospital mortality, length of stay, and total hospital cost. TriNetX included 1,601 adults: 276 in the antithrombin concentrate plus unfractionated heparin group and 1,352 in the bivalirudin group. Premier included 1,592 adults: 264 in the antithrombin concentrate plus unfractionated heparin group and 1,528 in the bivalirudin group.

After matching, antithrombin concentrate plus unfractionated heparin was linked with lower odds of thrombotic and bleeding events than bivalirudin alone. Length of stay and total hospital cost also leaned lower for patients prescribed antithrombin and unfractionated heparin. The data suggest a possible benefit, especially for ECMO patients with heparin resistance. The practical question is which tradeoff matters most in a given case: fewer clots, fewer bleeds, less time in the hospital, or lower cost.