Question 1 When completing this quiz, did you comply with Walden University’s Code of Conduct including the expectations for academic integrity? Answers: Yes No Question 2 The most common cancer found on the auricle is: Answers: Actinic keratosis Basal cell carcinoma Squamous cell carcinoma Acral-lentiginous melanoma Question 3 Which of the following medication classes should be avoided in patients with acute or chronic bronchitis because it will contribute to ventilation-perfusion mismatch in the patient?
Question 3 Which of the following medication classes should be avoided in patients with acute or chronic bronchitis because it will contribute to ventilation-perfusion mismatch in the patient?
Answer: Beta blockers
In patients with acute or chronic bronchitis, the use of beta blockers should generally be avoided due to the potential for causing ventilation-perfusion mismatch. Beta blockers are a class of medications commonly used to treat various cardiovascular conditions such as high blood pressure, angina, and heart failure.
The mechanism by which beta blockers can contribute to ventilation-perfusion mismatch in patients with bronchitis is through their effects on the bronchial smooth muscle tone. Beta blockers inhibit beta-adrenergic receptors, which normally mediate the relaxation of bronchial smooth muscle. By blocking these receptors, beta blockers can cause bronchoconstriction or narrowing of the airways, leading to decreased airflow and impaired ventilation.
In patients with bronchitis, which is characterized by inflammation of the bronchial airways, there is already an increased resistance to airflow due to the presence of inflammatory cells, mucus, and edema. The addition of beta blockers can further exacerbate this airflow obstruction, leading to increased ventilation-perfusion mismatch.
Ventilation-perfusion mismatch refers to the imbalance between the amount of air reaching the alveoli (ventilation) and the amount of blood reaching the alveoli (perfusion). In healthy individuals, ventilation and perfusion are closely matched to ensure efficient gas exchange. However, in patients with bronchitis, the impaired airflow combined with the vasoconstriction caused by beta blockers can result in a mismatch between ventilation and perfusion.
This ventilation-perfusion mismatch can have several consequences, including decreased oxygenation of the blood and impaired removal of carbon dioxide. The decreased oxygenation can lead to hypoxemia, which can manifest as symptoms such as shortness of breath, fatigue, and cyanosis. The impaired removal of carbon dioxide can result in hypercapnia, which can cause respiratory acidosis and further respiratory compromise.
Therefore, it is important to avoid the use of beta blockers in patients with acute or chronic bronchitis to prevent exacerbation of ventilation-perfusion mismatch and respiratory compromise. Instead, alternative medications that do not have bronchoconstrictive effects, such as calcium channel blockers or angiotensin-converting enzyme (ACE) inhibitors, may be considered for managing the cardiovascular conditions in these patients.
In conclusion, patients with acute or chronic bronchitis should avoid the use of beta blockers due to their potential to contribute to ventilation-perfusion mismatch. Beta blockers can cause bronchoconstriction and further impair airflow in individuals with already compromised bronchial airways. Alternative medications should be considered for managing cardiovascular conditions in these patients to prevent respiratory compromise and improve overall lung function.