PURPOSE: Acute pulmonary embolism and chronic obstructive pulmonary disease (COPD) exacerbation are difficult to distinguish by clinical signs and symptoms. Lung computed tomography angiography (CTA) and ventilation-perfusion (VQ) scans are currently used in the evaluation of pulmonary embolism (PE). The objective of the study was to investigate the incidence of PE in patients with acute COPD exacerbation and to assess the necessity of performing CTA or VQ scans in these patients.
METHODS: We retrospectively reviewed 3282 charts of all patients that presented to Cleveland Clinic emergency department between January 2001 and December 2006 with acute COPD exacerbation. We selected the cases that had a lung CTA or a VQ scan as the initial investigation for a possible PE.
RESULTS: VQ scans were initially done in 5 patients with COPD exacerbation and were all low probability for PE.CTA was performed in 74 of the 3282 patients with acute COPD exacerbation and was negative and indeterminate for pulmonary embolism in 68 and 5 patients, respectively. There were no positive CTA results. From the 6 patients that had an indeterminate CTA, 2 patients had a normal VQ scan, one patient had extensive lung metastasis, one patient had extensive pneumonia, and one patient had a mucus plug.
CONCLUSION: Our study failed to reveal an increased incidence of PE in patients with acute COPD exacerbation. None of the patients had a positive CT for pulmonary embolism. Thus, pulmonary embolism in the acute setting of COPD exacerbation is extremely unlikely.
CLINICAL IMPLICATIONS: Potentially harmful radiographic investigations like VQ scans or contrast loaded studies such as chest CTA should have a strong indication in order to be justified in the emergent setting of acute COPD exacerbation.
DISCLOSURE: Irina Timofte, No Financial Disclosure Information; No Product/Research Disclosure Information