Efficacy and safety of low-dose intravenous versus intramuscular vitamin K in parenteral nutrition patients.

Efficacy and safety of intravenous and intramuscular vitamin K were compared prospectively in patients receiving total parenteral nutrition. Sixty patients randomly received either a 1-mg daily iv injection (iv group) or a 10-mg weekly injection group (im group). Efficacy was determined by the prolongation of twice-weekly prothrombin (PT) and activated partial thromboplastin (APTT) times. The prolongation of both was not significantly different between the im and iv groups. The percent of PTs outside the normal range was not different for the two groups, although the iv group had more APTT values outside the range than did the im group (p = 0.002). The number of adverse reactions reported in the iv (5) and im (4) groups was also similar. Reactions were minor, not reproducible, and all patients recovered without sequelae. PT results from the iv and im groups were combined and compared to values from 28 patients in an earlier study who did not receive vitamin K. PTs in the no-vitamin K group were significantly prolonged over the vitamin K group (p = 0.0004). The results confirm that regular addition of vitamin K to TPN regimens decreases the incidence of elevated PTs. When administered appropriately, iv and im administration of vitamin K appear to be equally safe and effective in maintaining normal PTs and APTTs.