Incidence and Impact of Pulmonary Embolism During Severe COPD Exacerbation

Patients with COPD are at a high risk for pulmonary embolism (PE) because of systemic inflammation and co-existing comorbidities. We aimed to determine the incidence, risk factors, and impact of PE during COPD exacerbation requiring mechanical ventilation.

This prospective cohort study was conducted between March 2013 and May 2017. Subjects with severe COPD exacerbation requiring mechanical ventilation were included. A lower-limb ultrasonography or a multidetector helical computed tomography scan (MDCT) was performed according to Wells score. Subjects with ultrasonographic signs of phlebitis underwent MDCT to confirm PE.

During the study period, 131 COPD subjects were admitted to the ICU for severe COPD exacerbation. The incidence of PE was 13.7%. Factors independently associated with PE were increased sputum volume (odds ratio [OR] = 0.106, 95% CI 0.029-0.385, P = .001), recent immobilization ≥ 7 d (OR = 5.024, 95% CI 1.470-17.170, P = .01), age ≥ 70 y (OR = 5.483, 95% CI 1.269-23.688, P = .02), and invasive mechanical ventilation at ICU admission (OR = 3.615, 95% CI 1.005-13.007, P = .049). ICU mortality was higher in the PE group (44% vs 11%). Predictive factors of mortality were PE (OR = 7.135, 95% CI 2.042-24.931, P = .002), SAPS II score at admission OR = 1.040, 95% CI 1.005-1.077, P = .02), and duration of mechanical ventilation (OR = 1.098, 95% CI 1.044-1.154, P < .001).

PE was found to be a common etiology of severe exacerbation of COPD, leading to high mortality. Age, invasive mechanical ventilation, and immobilization were risk factors for PE.