RecommendationDo not offer additional pharmacological or mechanical prophylaxis for VTE to patients who are taking vitamin K antagonists and who are within their therapeutic range, providing anticoagulant therapy is continued.
Relative values of different outcomesThe outcomes considered important by the GDG were thromboembolic events (asymptomatic and symptomatic DVT, symptomatic pulmonary embolism and fatal pulmonary embolism), bleeding events (major bleeding, fatal bleeding and stroke) and other long term events occurring as a result of VTE (chronic thromboembolic pulmonary hypertension and post thrombotic syndrome).
Trade off between clinical benefit and harmsThe risk of developing venous thromboembolism is weighed against the increase risk in bleeding caused by pharmacological prophylaxis.
Economic considerationsThere is no relevant cost-effectiveness evidence specifically for this population subgroup.
Vitamin K antagonists (VKA) are shown to be an effective and cost-effective strategy in several groups of patient (Chapters 9 to 12). In the case of patients already on VKAs, they can obtain the benefits of prophylaxis without any additional drug and monitoring costs.
Quality of evidenceThere is evidence across a number of different populations that vitamin K antagonists are effective at reducing the risk of VTE.
Other considerationsDoses of anticoagulants used for treatment are usually higher than for prophylaxis use and so are likely to be suitable for reducing VTE risk although they will increase bleeding risk. .

From: 31, Patients requiring antiplatelet agents and anticoagulants for other reasons

Cover of Venous Thromboembolism
Venous Thromboembolism: Reducing the Risk of Venous Thromboembolism (Deep Vein Thrombosis and Pulmonary Embolism) in Patients Admitted to Hospital.
NICE Clinical Guidelines, No. 92.
National Clinical Guideline Centre – Acute and Chronic Conditions (UK).
Copyright © 2010, National Clinical Guideline Centre - Acute and Chronic Conditions.

Apart from any fair dealing for the purposes of research or private study, criticism or review, as permitted under the Copyright, Designs and Patents Act, 1988, no part of this publication may be reproduced, stored or transmitted in any form or by any means, without the prior written permission of the publisher or, in the case of reprographic reproduction, in accordance with the terms of licences issued by the Copyright Licensing Agency in the UK. Enquiries concerning reproduction outside the terms stated here should be sent to the publisher at the UK address printed on this page.

The use of registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant laws and regulations and therefore for general use.

The rights of National Clinical Guideline Centre - Acute and Chronic Conditions to be identified as Author of this work have been asserted by them in accordance with the Copyright, Designs and Patents Act, 1988.

PubMed Health. A service of the National Library of Medicine, National Institutes of Health.