Brief communication (Original). Pulmonary embolism in patients with chronic obstructive pulmonary disease and exacerbations of unknown origin

Background: Despite important advances in the diagnosis and treatment of acute pulmonary embolism (APE), diagnosis of pulmonary embolism (PE) is difficult in patients with chronic obstructive pulmonary disease (COPD) and exacerbation.

Objective: We evaluated PE in patients with chronic obstructive pulmonary disease and exacerbations of unknown origin.

Methods: Two-hundred and eight patients with COPD and severe exacerbations were studied. All patients had CT pulmonary angiography (CTPA) and lower limb ultrasonography. Arterial blood gas measurements, D-dimers and endothelin-1 (ET-1) levels were recorded.

Results: The frequency of PE was 33%. The following were more common in the PE group (χ² = 4.32-6.79, mean p < 0.05): immobilization ≥ 7 days; a ≥ 1 cm difference in edema of the lower limbs; deep venous thrombosis; syncope; S1Q3T3 syndrome; and a decrease in PaCO₂ ≥ 5 mm Hg. Plasma D-dimers and ET-1 levels were significantly higher in the PE group. Risk factors identified from logistic regression analysis were immobilization ≥ 7 days, ≥ 1 cm difference in lower limb edema, and deep venous thrombosis.

Conclusions: Overall, 33% of 208 patients had a PE, and the risk was greater in those who had been immobilized, those who had a ≥ 1 cm difference in edema of the lower limbs, and those who had a deep venous thrombosis.