Pulmonary Embolism in Patients with Chronic Lung Disease

Tompkins et al have written a scholarly examination of an important dilemma: the difficulty in suspecting a diagnosis of pulmonary embolism in patients with chronic dyspnea.1 The article has two parts, both of which make for worthwhile study. The article presents a concise discussion of the diagnosis and treatment of pulmonary embolism which even seasoned practitioners will find value in reading. The more important part of the article is a discussion of the difficulties facing a practitioner making a diagnosis of pulmonary embolism in patients with other causes for dyspnea.


Pulmonary Embolism in Patients with Chronic Lung Disease
Tompkins et al have written a scholarly examination of an important dilemma: the difficulty in suspecting a diagnosis of pulmonary embolism in patients with chronic dyspnea. 1 The article has two parts, both of which make for worthwhile study.The article presents a concise discussion of the diagnosis and treatment of pulmonary embolism which even seasoned practitioners will find value in reading.The more important part of the article is a discussion of the difficulties facing a practitioner making a diagnosis of pulmonary embolism in patients with other causes for dyspnea.
Part of the dilemma is left largely unspoken: the diagnosis of COPD has morphed from a specific problem with specific inclusion and exclusion criteria to a general catch all term for anyone with dyspnea or cough who has ever been near a lit cigarette.Although the exact ICD9 (10) code may vary, they all get treated as if they had exacerbation of COPD.
The other part of the dilemma was explicitly discussed at length: in which patients who present with worsening respiratory symptoms should we suspect pulmonary embolism?I find myself in substantial agreement with the authors with one addition to suggest and two minor disagreements with their conclusions.
It is imperative that practitioners treat diagnoses as works in progress rather than divine writs.We should always have an image of a projected clinical trajectory, and when the actual clinical picture deviates substantially from our projection, we must consider the possibility that our diagnosis is incorrect.The authors correctly point out that one should consider pulmonary embolism whenever we cannot find evidence for worsening airflow obstruction or some other credible pulmonary explanation for the worsening of symptoms.I would like to add to this thought: serial spirometry values are helpful.Whenever one of my COPD patients complain of worsening dyspnea, and the FEV1 is unchanged (or even improved) compared with baseline, and there are objective findings to match the subjective complaints, I consider other diagnoses with pulmonary embolism at the top of the list.In my own practice I have made the diagnosis of pulmonary embolism at the time of presentation a number of instances when these conditions presented themselves.
The other situation the authors discussed was the patient who fails to respond to treatment as expected.This is another variation on the theme of deviation from projected trajectory.Unfortunately, this is where the problem of conflating COPD with every respiratory ailment raises its ugly head.One can hardly expect patients without COPD to respond to treatment for COPD.The authors do not make this mistake, but others frequently do.
Even when the diagnosis of COPD is correct, not all patients with COPD respond rapidly to steroids.In a previous article in this journal, 2 I suggested stages of COPD based on steroid responsiveness.If a patient has responded slowly (or not at all) to therapy in the past, one could hardly expect the patient to promptly improve with treatment.Should we obtain CT-PA in every hospitalization for one of these patients?I think not.This situation will require very astute clinical judgment to discern a substantial