51. A 45-year-old patient tells an advanced practice registered nurse (APRN) about a productive cough that is worse in the morning. The sputum is clear or white. Shortness of breath occurs with exertion, especially after exercise. The patient reports smoking a half a pack of cigarettes each day for the past 15 years. Vital signs are within normal limits with the exception of a respiratory rate of 26 breaths per minute. Assessment reveals rhonchi and wheezing bilaterally. The APRN suspects that chronic obstructive pulmonary disease (COPD) is present and performs a diagnostic test to confirm the suspicion. Which diagnostic test result supports the APRN's diagnosis?
Answer: B
CXR reveals hyperinflation and flattening of diaphragm
The presence of hyperinflation and flattening of the diaphragm on a chest X-ray (CXR) is indicative of chronic obstructive pulmonary disease (COPD). These findings are characteristic of COPD, as they reflect the changes in lung structure and function that occur due to chronic airflow limitation.
A) Results of CBC show low hematocrit
Low hematocrit levels in a complete blood count (CBC) may suggest various conditions, such as anemia, but do not specifically indicate COPD. While anemia can occur in chronic disease states, this option does not directly support the diagnosis of COPD or reflect the patient's respiratory condition.
B) CXR reveals hyperinflation and flattening of diaphragm
This option correctly identifies the diagnostic test result that supports the diagnosis of COPD. Hyperinflation of the lungs is a common radiographic finding in COPD patients, and the flattening of the diaphragm indicates the loss of lung elasticity and chronic over-inflation, which are hallmarks of the disease.
C) Forced expiratory volume 1 is 80%
A forced expiratory volume in one second (FEV1) of 80% may indicate normal lung function or mild obstruction, but it does not confirm a diagnosis of COPD. COPD is typically characterized by a significant reduction in FEV1, usually below 70% of predicted, reflecting more severe airflow limitation.
D) Peak flow is 75%
A peak flow measurement of 75% may suggest some level of airway obstruction but does not provide the definitive evidence needed to confirm a COPD diagnosis. Moreover, peak flow values are more commonly used in the context of asthma management, making this option less relevant for diagnosing COPD.
Conclusion
The chest X-ray finding of hyperinflation and flattening of the diaphragm is the most definitive indicator of chronic obstructive pulmonary disease among the options presented. Other options either do not specifically relate to COPD or do not indicate the severity of the condition accurately. Thus, the CXR result is critical in confirming the APRN's suspicion of COPD based on the patient's symptoms and history.