[Utility of the clinical models for predicting pulmonary thromboembolism]

We considered to evaluate the efectivity of the clinical models for predicting pulmonary thromboembolism (PE).

Retrospective application of three published clinical models (Wells or Canadian model, Geneva model and Pisa model) to patients unequivocally diagnosed of acute PE.

We evaluate 120 patients [Mean age 71+/-13 years, males 63 (52%)]: Nineteen (16%) diagnosed with pulmonary arteriography and 101 (84%) diagnosed with helical computed tomography. In the Canadian model 24% patients were of high clinical probability, 59% intermediate and 17% low clinical probability. In Geneva model 21% patients belonged to high clinical probability, 69% intermediate and 10% low clinical probability. In Pisa model 49% patients were of high clinical probability, 45% intermediate and 6% of low clinical probability. Sensitivity was 0.59, 0.67 and 0.89 respectively. Factors associated with low probability were in Canadian model the heart rate, the absence of signs of deep venous thrombosis, the presence of an alternative diagnosis and the low rate of cancer. In Geneva model, age, normal heart rate and PaO2 higher 70 mm Hg were associated with low probability, while in Pisa model normal chest X-Ray and radiological signs of pulmonary oedema were also associated with low clinical probability.

Although all three clinical model showed deficiencies Pisa model was the most suitable clinical model for predicting PE. An intermediate clinical probability in the three models, should not serve to rule out PE, besides it is remarkable that patients with low clinical probability still could have PE, providing for clinical models with a limited value.