Combined risk tool predicts PE in respiratory emergency patients
MedWire News: A risk-prediction tool that combines components of Wells' rule and the Geneva score detects pulmonary embolism (PE) in acute respiratory patients with greater accuracy than each of the individual methods alone, research shows.
"The initial management of suspected pulmonary embolism (PE) is [often] done in respiratory departments, but is based on clinical prediction rules developed in other settings," note Angeliki Tsimogianni and co-investigators from the National and Kapodistrian University of Athens, in Greece.
The researchers therefore assessed the accuracy of Wells' rule, and the original and revised Geneva scores in 183 patients presenting to a respiratory emergency department. The majority of patients had chronic respiratory or other comorbidities, such as chronic obstructive pulmonary disease (COPD), asthma, cancer, obesity, and congestive heart failure.
Using various imaging techniques, the researchers confirmed PE in 52 patients and ruled it out in the remaining 131.
Individual constituents of the Wells' and Geneva clinical prediction criteria that were significantly associated with the presence of PE included tachycardia, atelectasis, elevated hemidiaphragm, clinical signs of deep vein thrombosis, physician perception that PE is the likeliest diagnosis, and previous thromboembolism.
Chest pain and the absence of COPD or cough - symptoms that are not included in the prediction rules - also independently predicted PE in these patients.
In contrast, recent surgery/immobilization combined, hemoptysis, cancer, age, and partial pressure of oxygen were not related to PE, indicating that some components of existing PE prediction tools perform better than others in patients with acute-onset respiratory complaints, Tsimogianni and co-authors remark.
The researchers combined the independent predictors of PE from both Wells' and the Geneva criteria to develop a clinical prediction tool tailored to patients with respiratory emergencies.
Receiver-operator characteristic (ROC) analysis showed that the combined tool had the greatest accuracy for PE prediction with an area under the curve of 0.92, compared with 0.86, 0.83, and 0.75 for Wells' rule, the revised Geneva score, and the original Geneva score, respectively.
Of the PE risk prediction rules currently available, the Wells' rule is the most "useful in diagnosing PE in respiratory emergencies," comment Tsimogianni et al in the journal Thrombosis Research.
However, the combination of chest pain and the absence of cough and COPD with components of established scores resulted in a new, more accurate rule for PE risk stratification, "which deserves further validation," they conclude.
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By Laura Dean