The rationale for these diagnoses is that difficulty breathing with exertion explains cardiopulmonary or pulmonary disease. Moreover, pursed-lip breathing is a sign of airflow obstruction. Dyspnea on exertion worsens with the resulting sedentary state. This is present in patients with cardiopulmonary disease. In regard to this case study, the patient has a past medical history of COPD; thus, skeletal muscle atrophy is a common finding and has been related to low-level systemic inflammation and oxidative stress (Nelson, 2015).
To further develop the differential diagnosis, a review of systems ought to be conducted. This entails questions that need to be addressed. Such questions include dental changes, occupational exposure to dust and chemicals, excessive salt intake, weight gain, increased cough, fever, and increasing sputum production (Markovchick, Pons, & Bakes, 2011).
The final primary diagnosis is COPD. The symptoms include a cough, sputum production, and dyspnea on exertion (Osadnik, McDonald, Jones & Holland, 2012). In this particular case, the patient has a significant cigarette smoking history, thus, the worsening dyspnea. This is because the increase in dyspnea is linked with age (the patient is 70 years), deconditioning, weight gain and concomitant comorbid medical conditions.
Further diagnostic workup includes obtaining a spirometry before and after bronchodilator; as the first step. This step will determine any airflow obstruction thus grant patients immediate therapy. Additionally, lung volume ought to be measured, so as to reveal hyperinflation (Buttaro, 2013). Also, thoracic imaging ought to be performed with an MRI, as well as pulse oximetry test and arterial blood gas measurements.