Venous thromboembolism in medical inpatients--the silent epidemic of neglect
Authors: Kyle Perrin, Philip Robinson, Richard Beasley
Journal: Journal of the Royal Society of Medicine (2005)

Why is the use of venous thromboembolism (VTE) prophylaxis for acutely ill medical patients so poor among internal medicine physicians?1–5 What can be done to improve practice?

The first requirement is to recognize the burden of VTE in medical inpatients. The baseline risk of VTE in patients admitted to hospital with medical disorders is around 15%.6 Hospitalization for an acute medical illness accounts for around one in five cases of all symptomatic VTE events in the general population.7 This would suggest that effective prophylaxis of medical inpatients represents an important measure available to reduce the burden of VTE in the general population.

The next requirement is to recognize the efficacy and safety of prophylactic measures to reduce the recurrence of VTE in this clinical situation. There is now substantive evidence that in medical inpatients, the use of low molecular weight heparin (LMWH) reduces the risk of symptomatic VTE by over 50% across the broad spectrum of disorders including sepsis, heart failure and respiratory disease.6 The use of LMWH has been shown to be safe with a minimal increase in the absolute risk of major bleeding. There is also likely to be some benefit, although less substantial with the use of graduated compression stockings.

The third issue is that of cost-effectiveness. In this regard several economic analyses have concluded that LMWH is a cost-effective prophylactic intervention in medical inpatients.8,9

The fourth issue is whether clear evidence-based guidelines are available. A number of consensus guidelines have been promoted, the most up-to-date being the American College of Chest Physicians guidelines6 which state:


In acutely ill medical patients who have been admitted to the hospital with congestive heart failure or severe respiratory disease, or who are confined to bed and have one or more additional risk factors, including active cancer, previous VTE, sepsis, acute neurologic disease, or inflammatory bowel disease, we recommend prophylaxis with LDUH (Grade 1A) or LMWH (Grade 1A).

In medical patients with risk factors for VTE and in whom there is a contraindication to anticoagulant prophylaxis, we recommend the use of mechanical prophylaxis with graduated compression stockings or intermittent pneumatic compression.


With this evidence base, it should be of concern to all physicians to read the findings of Rashid et al. published in this issue of the Journal.10 They report a gross under-utilization of thromboprophylaxis in medical patients admitted to two NHS teaching hospitals in England. Less than one in three moderate to high-risk patients received any form of prophylaxis and the intervention (which involved a single presentation of both the audit results and recommended guidelines to a large clinician group) was ineffective.

The authors considered the possible reasons why there is not a better uptake of thromboprophylactic measures by physicians. They propose that there is likely to be a perception that VTE is very uncommon, given that most events are subclinical. There may also be an overestimation of the perceived bleeding risk, or the cost of routine LMWH use. It is also conceivable that when doctors are admitting medical patients with complex problems, the need for thromboprophylaxis assumes a lesser priority than management of the severe illness.

The authors also raised the approaches that might be considered to improve current practice, recognizing that their intervention was unsuccessful in increasing the rate of thromboprophylaxis. They suggest that we might follow the example of our surgical colleagues who have successfully employed a number of strategies, including the use of risk assessment protocols with prophylactic strategies recommended at each level of risk, targeting of vulnerable patient subgroups and undertaking regular audit. There are also a number of initiatives that have been implemented in medical inpatients with successful outcomes. One approach has been the use of a single page evidence-based risk assessment tool incorporated in the standard admissions packs promoted through medical training programmes.11 More recently it has been shown that an automatically generated computer alert to physicians which includes both magnitude of risk and recommended prophylactic measures not only increases thrombophrophylaxis, but also a reduction in the overall rate of VTE.12

Ultimately however, it comes down to each individual physician taking responsibility for being aware of the evidence base and responding accordingly. Given that guidelines are so widely available, and agreed by experts internationally, the current low level of thromboprophylaxis can be considered unacceptable.