New risk assessment tool aims to help nurses prevent VTE
The Department of Health has published a thromboembolism risk assessment strategy, recommended for use with all patients on admission to hospital. Nerys Hairon reports
The Department of Health has published a tool for use in assessing hospital patients’ risk of venous thromboembolism (VTE) (DH, 2008a; 2008b). The condition is responsible for the deaths of around 25,000 hospital patients in England each year.
The tool is recommended for use with all patients on admission to hospital and was developed after an expert group recommended that hospital patients be assessed for risk of VTE (DH and CMO, 2007). Announcing the launch of the tool, the chief medical officer for England, Sir Liam Donaldson, said it had the potential to save thousands of lives each year.
The risk assessment includes a series of patient-related risk factors (click here) and involves a three-step process (see Box 1). Nurses can use it to systematically evaluate patients’ risk on admission. Go to dh.gov.uk/VTE to download the tool.
Venous thromboembolism is the formation of a blood clot (thrombus) in a vein. This may dislodge from its site of origin to cause an embolism. Most thrombi occur in the deep veins of the legs - this is known as deep vein thrombosis (DVT). Dislodged thrombi may travel to the lungs - this is called a pulmonary embolism (PE) and can be fatal. Thrombi can also cause long-term morbidity because of venous insufficiency and post-thrombotic syndrome, potentially leading to venous ulceration.
Background to risk assessment
The publication of the risk assessment is the culmination of several years of work to prevent VTE.
The Commons health select committee reported on the prevention of VTE in hospitalised patients in March 2005 (House of Commons Health Committee, 2005). In its published response, the government recognised there was no systematic approach to identifying patients at risk of VTE in hospital and there was significant room for improvement (DH, 2005).
Ministers asked for a VTE expert group to be set up to look at how best practice and guidance could be implemented.
The working group recommended that a documented mandatory risk assessment should be carried out on every hospitalised patient on admission (DH and CMO, 2007), and that this should be embedded within the Clinical Negligence Scheme for Trusts.
The group called for the DH to set core standards for the NHS and the independent sector, to ensure ‘there is ultimately 100% compliance with the requirement for risk assessment of each and every adult admitted to hospital in England’. It added that the Healthcare Commission should monitor compliance through its assessment and inspection procedures.
The DH and CMO (2007) also recommended that public and professional understanding of VTE should be improved at a national level, through better communication of information to patients and the public. This should be accompanied by improved and coordinated programmes of professional education.
Following publication of the group’s report, an implementation working group was established to develop a risk assessment and raise awareness of VTE.
BOX 1: Risk assessment for VTE
Source: DH (2008b)
The DH’s VTE expert working group made a number of recommendations on preventing VTE in clinical practice (DH and CMO, 2007).
It said all medical patients should be considered for thromboprophylaxis. In particular, this applies to those who are likely to be in hospital for longer than four days and have reduced mobility, with severe heart failure, respiratory failure (due to exacerbation of chronic lung disease or pneumonia), acute infection, inflammatory illness or cancer (with additional risk factors for VTE).
Such patients should be considered for a regimen involving heparins. While both unfractionated and low-molecular weight forms are effective preventive treatments, low-molecular weight heparins (LMWH) are the preferred prophylactic. Aspirin was not recommended for thromboprophylaxis in medical patients.
The expert group did not recommend mechanical methods of prevention as these had not yet been evaluated in acutely ill medical patients (DH and CMO, 2007). It also made recommendations for intermediate-risk and low-risk surgical patients. For high-risk surgical/orthopaedic patients it referred practitioners to the relevant NICE (2007) guidance.
NICE (2007) guidance covers all adult patients admitted to hospital for surgery requiring an overnight stay and focuses on procedures carrying a high risk of VTE (Hairon, 2007). Formation of thrombi is associated with inactivity and surgical procedures, and the risk rises with the duration of surgery and period of immobility.
The guidance contains a section on each of the following procedures:
Elective orthopaedic surgery (for example total hip or knee replacement);
Hip fracture surgery;
Gynaecological surgery (excluding caesarean section);
Neurosurgery (including spinal surgery);
Practitioners are advised to exercise their clinical judgement when making decisions on the appropriateness of VTE prophylaxis for patients undergoing other procedures requiring an inpatient stay.
The NICE guidance outlines a number of key priorities, focusing on risk assessment, patient information, mechanical prophylaxis, drug prophylaxis and early mobilisation.
Healthcare staff should assess patients to identify their risk factors for developing VTE and give them verbal and written information, before surgery, about the risks of VTE and the effectiveness of prophylaxis.
Inpatients having surgery should be offered thigh-length graduated compression/anti-embolism stockings from the time of admission unless contraindicated (for example in patients with established peripheral arterial disease or diabetic neuropathy).
If thigh-length stockings are inappropriate for reasons of compliance or fit, the guidance says that knee-length stockings may be used as an alternative.
Intermittent pneumatic compression or foot impulse devices may be used as alternatives or in addition to graduated compression/anti-embolism stockings while patients are in hospital.
In addition to mechanical prophylaxis, patients at increased risk of VTE due to individual risk factors and those having orthopaedic surgery should be offered LMWH. Fondaparinux, within its licensed indications, may be used as an alternative to LMWH. For hip-fracture patients, LMWH/fondaparinux therapy should be continued for four weeks after surgery; this also applies to those having a hip replacement who have one or more risk factors for VTE.
NICE says that regional anaesthesia carries a lower risk of VTE than general anaesthesia. Its suitability for an individual patient and procedure should be considered, along with patient preferences, in addition to any other planned method of thromboprophylaxis.
Practitioners should encourage patients to be mobile as soon as possible after surgery. See www.nice.org.uk for guidance details.
The VTE risk assessment tool is available for use by all hospitals and, according to the DH, has the potential to prevent many avoidable deaths. It was developed with key stakeholders, including NICE. Supporting guidance from NICE for all hospital patients is scheduled for publication in autumn 2009.
The tool states that risk assessment should be undertaken on all patients on admission to hospital.
In addition, it is recommended that all patients are periodically reassessed during their inpatient stay as their risk of VTE may change, and reassessment after at least 48-72 hours is recommended (DH, 2008b).
The risk assessment tool is not intended for use in pregnant women, for whom practitioners should refer to Royal College of Obstetricians and Gynaecologists guidance for obstetric patients (RCOG, 2004).
The risk assessment presents a simple three-step guide to patient evaluation, with risk factors clearly outlined. It should help nurses to improve patient care, by standardising risk assessment practice.
Department of Health (2008a) Hospital Patients to be Assessed for Risk of Blood Clots. Press release. London: DH.
Department of Health (2008b) Risk Assessment for Venous Thromboembolism (VTE). London: DH.
Department of Health (2005) Government Response to the House of Commons Health Committee Report on the Prevention of Venous Thromboembolism in Hospitalised Patients - Second Report of Session 2004-05. London: DH.
Department of Health, Chief Medical Officer (2007) Report of the Independent Expert Working Group on the Prevention of Venous Thromboembolism in Hospitalised Patients. London: DH.
Hairon, N. (2007) Prevention of venous thromboembolism in patients. Nursing Times; 103: 18, 23-24.
House of Commons Health Committee (2005) The Prevention of Venous Thromboembolism in Hospitalised Patients. Second Report of Session 2004-05. London: DH.
NICE (2007)Venous Thromboembolism: Reducing the Risk of Venous Thromboembolism (Deep Vein Thrombosis and Pulmonary Embolism) in Inpatients Undergoing Surgery. London: NICE.
Royal College of Obstetricians and Gynaecologists (2004) Thromboprophylaxis During Pregnancy, Labour and After Vaginal Delivery. London: RCOG.