A tailored dose of oral vitamin K increased the proportion of over-anticoagulated patients returning to target INR within 24 hours compared to a fixed-dose regimen (68.9% vs. 52.8%; P=0.026).
RCT (n=181)
randomly allocated
Does a tailored dose of oral vitamin K improve the proportion of over-anticoagulated patients returning to target INR within 24 hours compared to a fixed dose?
Tailored dosing of oral vitamin K based on index INR and body surface area is more effective than fixed dosing at returning over-anticoagulated patients to their target INR within 24 hours.
Absolute Event Rate: 68.9% vs 52.8%
p-value: p=0.026
Current guidelines advocate using fixed-doses of oral vitamin K to reverse excessive anticoagulation in warfarinised patients who are either asymptomatic or have minor bleeds. Over-anticoagulated patients present with a wide range of International Normalised Ratio (INR) values and response to fixed doses of vitamin K varies. Consequently a significant proportion of patients remain outside their target INR after vitamin K administration, making them prone to either haemorrhage or thromboembolism. We compared the performance of a novel tailored vitamin K dosing regimen to that of a fixed-dose regimen with the primary measure being the proportion of over-anticoagulated patients returning to their target INR within 24 h. One hundred and eighty-one patients with an index INR > 6·0 (asymptomatic or with minor bleeding) were randomly allocated to receive oral administration of either a tailored dose (based upon index INR and body surface area) or a fixed-dose (1 or 2 mg) of vitamin K. A greater proportion of patients treated with the tailored dose returned to within target INR range compared to the fixed-dose regimen (68·9% vs. 52·8%; P = 0·026), whilst a smaller proportion of patients remained above target INR range (12·2% vs. 34·0%; P < 0·001). Individualised vitamin K dosing is more accurate than fixed-dose regimen in lowering INR to within target range in excessively anticoagulated patients.
Kampouraki et al. (Wed,) conducted a rct in Over-anticoagulation (n=181). Tailored dose of oral vitamin K vs. Fixed-dose (1 or 2 mg) of oral vitamin K was evaluated on Proportion of over-anticoagulated patients returning to their target INR within 24 h (p=0.026). A tailored dose of oral vitamin K increased the proportion of over-anticoagulated patients returning to target INR within 24 hours compared to a fixed-dose regimen (68.9% vs. 52.8%; P=0.026).