Hospital referral of DVT patients
11 March 2014
Research published this week in the authoritative British Medical Journal shows that referral to a hospital, which is the standard procedure when a GP suspects that a patient has deep vein thrombosis (DVT), is no longer necessary in one out of three cases. A new decision model may save the patient a visit to hospital.
In the Netherlands DVT is diagnosed in around 40,000 patients each year. DVT is caused by a blood clot that forms in the leg veins. Because symptoms of DVT are sometimes non-specific, every year around 400,000 patients visit a GP with symptoms that may indicate DVT. The GP often refers these patients to hospital for further examination.
Decision model and blood test
More than 20 years ago researchers from Canada showed that DVT can be safely excluded by using a standard questionnaire, combined with a simple blood test (to determine the D-dimer, a substance that is only present in the blood when there is or has been a clot). The combination of questionnaire and blood test indicates the likelihood of DVT. If this probability is low, the patient does not need to be referred to hospital. This method is currently being recommended in guidelines for GPs as well as hospitals.
Diversity of people
However, many doctors are concerned that the current method is not always sufficiently safe for specific groups of patients, such as cancer patients or patients who have previously had DVT. There is also doubt as to whether GPs have adequate experience to be able to safely exclude DVT. Previous studies have shown that ‘in general’ the method is safe but not whether that is also true for specific groups of patients. The scale of the previous studies was simply too small to be able to answer this question and, as a result, GPs often continued to refer their patients to hospital.
Individual patient care
Researchers at University Medical Center (UMC) Utrecht, working in collaboration with researchers from other countries, have combined the results of 13 previous studies (conducted throughout the world) into one large patient database of more than 10,000 patients with potential DVT. Speaking about this, research physician dr. Geert-Jan Geersing, lead author of the article, says: “With this new database it was possible, for the first time, to study different patient groups with potential DVT. The study shows that for almost all patients with potential DVT the use of the questionnaire plus the blood test is a safe manner of being able to exclude DVT.”
This method of diagnosis also appears to be safe and reliable when used by GPs. However, the method is not as reliable in cancer patients and they must therefore still be referred to hospital if DVT is suspected. The new decision model allows customized patient care geared to the individual patient, whereby the treatment of DVT can be undertaken more often by the GP: close to home and also an excellent approach for reducing the increasing costs of care.