Padua Score For VTE Risk Calculator

How does this Padua score for VTE risk calculator work?

This is a health tool that evaluates the risk for inhospital patients to develop VTE (venous thrombembolism). This is basically a mean of risk stratification and beginning of clinical prophylaxis measures in the management of patients who are likely to exhibit some of the VTE risk factors.

The 11 variables taken into account in this Padua score calculator and some considerations about them, useful in the administration of the score are provided below:

■ Active cancer [+3] – or under chemotherapy or XRT within the last six months;

■ Previous VTE [+3] – without including any superficial thromboses;

■ Decreased mobility [+3] – of at least three days duration;

■ Thrombophilia [+3] – a preexisting hypercoaguable state, defects of antithrombin, protein C or S;

■ Previous trauma or surgery within that last 4 weeks [+2];

■ Age ≥70 [+1];

■ Heart and/or respiratory failure [+1] – including CHD;

■ Ischemic stroke or acute myocardial infarction [+1];

■ Acute rheumatologic disorder and/or acute infection [+1];

■ Obesity [+1] – catalogued at a body mass index (BMI) equal to or higher than 30;

■ Hormonal therapy [+1] – intercurrent HRT.

The original study, conducted at the University of Padua, hence the title, also made a follow up at 3 months after admission to evaluate the incidence of symptomatic VTE (diagnosed with D-dimer)  and compared it to the preliminary results during the first administration of the score.

The other diagnosis testing comprises of compression ultrasonography of the whole deep vein system in the case of suspected DVT; spiral CT or V/Q scanning of the lungs to search for pulmonary embolism.

An important aspect was that all patients admitted on the study to not be on full-dose anticoagulant therapy and have no contraindication to be started on pharmacological prophylaxis, therefore didn’t present any of the following:

■ recent or ongoing major bleeding;

■ platelet count lower than 100 × 10⁹ L;

■ creatinine clearance lower than 30 mL/min;

■ pregnant;

■ under 18 years.

The application of RAM methods such as the Padua score is even more important as it is estimated that less half of the VTE high risk patients receive adequate prophylaxis during their hospital stay, even patients with history of VTE are sometimes overlooked.

One of the criticisms received by the method though refers to the lack of proper validation and whether it will actually be largely adopted in clinical usage to increase prophylaxis initiation.

At the same time, there is also the presence of other risk factors of importance that might be ignored in the score, especially those involved with thrombin generation.

Padua score interpretation

The 11 variable presented above each weigh a different number of points. If the user answers positive to either of them, that number of point is awarded and then contributes to the overall score. The final Padua result ranges from 0, with no positive answer in any of the variables to 20, with all variables being described as present.

The score discriminated between low and high risk at a cut off of 4 as follows:

■ Scores ≥4 are high risk for VTE and subsequent complications; recommendation for thromboprophylaxis;

■ Scores <4 are low risk.

References

1) Barbar S, Noventa F, Rossetto V, Ferrari A, Brandolin B, Perlati M, De Bon E, Tormene D, Pagnan A, Prandoni P. (2010) A risk assessment model for the identification of hospitalized medical patients at risk for venous thromboembolism: the Padua Prediction Score. J Thromb Haemost; 8(11):2450-7.

2) Vardi M, Ghanem-Zoubi NO, Zidan R, Yurin V, Bitterman H. (2013) Venous thromboembolism and the utility of the Padua Prediction Score in patients with sepsis admitted to internal medicine departments. J Thromb Haemost; 11(3):467-73.

3) Heit JA, O'Fallon WM, Petterson TM, Lohse CM, Silverstein MD, Mohr DN, Melton LJ 3rd. (2002) Relative impact of risk factors for deep vein thrombosis and pulmonary embolism: a population-based study. Arch Intern Med; 162(11):1245-8.

4) Francis CW. (2007) Clinical practice. Prophylaxis for thromboembolism in hospitalized medical patients. N Engl J Med; 356(14):1438-44.

5) Saliba W, Zahalka W, Goldstein L, Ron G, Elias M. (2014) Padua prediction score and thrombin generation in hospitalized medical patients. Thromb Res; 134(4):803-6.