Enteral feeding deficient in vitamin K. Is there a related substantial bleeding risk?

Abstract
Vitamin K is essential for clotting factors II, VII, IX and X to be released in their active form. Under vitamin K deficiency a coagulopathy may develop that is marked by prolongation of the prothrombin time (PT). Patients receiving enteral feeding which does not cover the daily vitamin K requirements might be predisposed to develop a bleeding diathesis. Yet, current guidelines do not recommend monitoring the PT in patients receiving enteral feeding. In the present cross-sectional study, we assessed the prevalence of a prolonged PT in patients receiving long-term enteral feeding with one or a combination of the enteral formulas Osmolite®, Jevity®, Easymilk®. Sixty residents in long-term geriatric care received exclusively enteral feeding for a median 27 months (average 34.7, SD 29). The median daily vitamin K supplied by enteral feeding was 63.5 mcg (average 8.3, SD 17.2), i.e. less than the 150 mcg recommended by the Food and Drug Administration. In 57 patients the PT-INR was 0.9 - 1.2 (normal); the PT-INR was prolonged to 1.4 in 3 patients. There were 6 episodes of major bleeding and 4 episodes of minor bleeding during the study period, unrelated to prolonged PT and distributed at random along the time of enteral feeding. Accordingly, long-term vitamin K-deficient enteral nutrition did not affect vitamin K-dependent coagulation. This may argue against the need to regularly monitor the PT in patients receiving long-term enteral nutrition