Wells score

The Wells Score is a validated scoring system for the clinical assessment of the probability of the presence of pulmonary embolism (LE) or deep vein thrombosis (DVT).

The advantages of a validated scoring system for diagnostic confirmation are, on the one hand, that the accuracy of clinical statements can be increased if the risk is assessed by anamnestic assessment beforehand, and on the other hand, that potentially life-threatening situations and disease progression can be better predicted and prevented.

Deep vein thrombosis (DVT):

A DVT is a partial or complete dislocation of deep veins (especially leg veins), which can increase in size over time and can cause pulmonary embolism. Since this clinical picture is potentially lethal and the aim is to prevent consequential damage caused by DVT, such as postthrombotic syndrome, it is advisable to make an early diagnosis and initiate therapy. This can prevent consequential damage such as postthrombotic syndrome or pulmonary embolism.

First and foremost is clinical diagnostics, which can predict the probability of the presence of DVT using the Wells Score. Subsequently, laboratory diagnostic tools (determination of D-dimers) as well as imaging can be connected for reliable exclusion.

Wells-Score for the probability of the presence of DVT see Table 1

Evaluation:

If the probability is not high: with normal D-dimers no further diagnostics necessary

In case of high clinical probability: no D-dimer test, but direct further diagnostics

It is important to emphasize that the Wells score alone does not completely rule out DVT if there is a low probability and a high score does not prove the presence of DVT. Nevertheless, the Wells Score is a good help to make a better assessment and, in combination with the removal of D-dimers, to make a decision about the necessity of imaging.

Pulmonary embolism (LE): An LE refers to a partial/full blockage of the pulmonary arteries due to thrombi that have been introduced from the periphery. A LE is a highly acute condition and often lethal within a few hours. Due to the potentially life-threatening situation, every suspected case of LE should be diagnosed quickly and, if there is a high clinical probability, therapy should be initiated directly.

For clinical diagnosis, the Wells-Score is the most important factor in hemodynamically stable patients, which can predict the probability of the presence of an LE.

Wells-Score for the probability of the presence of an LE see table 2

Evaluation:

If the probability is not high: for normal D-dimers no further diagnosis necessary, for positive D-dimers: echo, troponin

In case of high clinical probability: no D-dimer test, but direct further imaging diagnostics: CT-Angio

It is important to emphasize that the wells score alone cannot completely exclude an LE if there is a low probability and on the other hand a high score does not prove the existence of an LE. Nevertheless, the Wells-Score is a good help to make a better assessment and in combination with the removal of D-dimers to make a decision about the necessity of imaging. With regard to LE it is especially important to emphasize that D-dimer testing should be performed using a highly sensitive test procedure.

Deep vein thrombosis section - overview

Section Pulmonary embolism

1. Chunilal SD et al. Does this patient have pulmonary embolism. 290:2849-2858
   .AWMF, S2k guideline for the diagnosis and therapy of venous thrombosis and pulmonary embolism. AWMF Guideline Venous Thrombosis-Pulmonary Embolism.
2. Herold G et al (2018) Internal Medicine, Herold Verlag pp. 828, 843
3. Wells PS et al (1997) Value of assessment of pretest probability of deep-vein thrombosis in clinical management. Lancet 350:1795-1798.
4. Wells PS et al (2003) Evaluation of D-dimer in the diagnosis of suspected deep-vein thrombosis. N Engl J Med 349:1227-1235.
5. Wells PS et al (2000) Derivation of a simple clinical model to categorize patients with a probability of pulmonary embolism: increasing the models utility with the SimpliRED D-dimer. Thromb haemost 83:416-420.
6. Wells PS et al (2001) Excluding pulmonary embolism at the bedside without diagnostic imaging: management of patients with suspected pulmonary embolism presenting to the emergency department by using a cimple clinical model and d-dimer. Ann Internal Med 135:98-107.