An algorithm for preventing bypass-associated dilutional (BAD) coagulopathy: Theory and example

Abstract

Crystalloid administered during cardiopulmonary bypass may significantly dilute clotting factor concentrations, particularly in low blood volume patients. Should the administered fluid (pump prime plus IVs) drop the clotting factor concentrations below approximately 38%, almost all patients will bleed, heparin levels will be overestimated and excessive neutralizing protamine will be administered. This combination can render blood virtually unclottable. This paper describes algorithms that quantify dilution risk and the maximum fluid that can be safely administered. A confirmatory calculation to prevent excessive protamine administration is also described.