Question

Sam, age 78, presents to the clinic w/respiratory symptoms. His PFTs are as follows: normal total lung capacity, decreased PaO2, increased PaCO2. On assessment, you auscultate course crackles and forced expiratory wheezes. What is your dx?

Answer 1

The most likely diagnosis for Sam, given his symptoms and PFT results, is chronic obstructive pulmonary disease (COPD), which is characterized by airway abnormalities, impaired gas exchange, and common auscultation findings such as wheezes and crackles.

Step-by-step explanation:

Based on the presentation of normal total lung capacity, decreased PaO2, increased PaCO2, along with auscultation findings of course crackles and forced expiratory wheezes, the likely diagnosis for Sam is chronic obstructive pulmonary disease (COPD). COPD is a common respiratory condition, particularly in older individuals who may have a history of smoking. The condition is characterized by persistent respiratory symptoms like shortness of breath and chronic cough with sputum production, and by airflow limitation due to airway and/or alveolar abnormalities, often caused by significant exposure to noxious particles or gases.

The symptoms Sam is experiencing, such as decreased PaO2 (hypoxemia) and increased PaCO2 (hypercapnia), are indicative of the impaired gas exchange that occurs in COPD. Furthermore, the presence of wheezes and crackles upon auscultation are typical findings in someone with this disease. It is important to note that while COPD can present similar to pneumonia, the normal total lung capacity observed in the pulmonary function tests (PFTs) leans more towards COPD, as pneumonia would often cause a restrictive pattern with reduced lung volumes.