During an asthma attack, what pathophysiological process leads to the wheezing sound?
Overproduction of surfactant
Airway narrowing due to bronchospasm
Accumulation of fluid in the alveoli
Thickening of alveolar walls
The Correct Answer is B
A. Overproduction of surfactant: Surfactant is a lipoprotein that reduces surface tension in the alveoli to prevent their collapse. An overproduction would not lead to the musical whistling sound of wheezing. Asthma is a disease of the conducting airways, not a primary disorder of surfactant production or alveolar tension.
B. Airway narrowing due to bronchospasm: During an attack, inflammatory triggers lead to the contraction of bronchial smooth muscle and mucosal edema. This narrows the lumen of the bronchioles, creating high-velocity, turbulent airflow as air is forced through the constricted passages. This turbulence produces the characteristic high-pitched wheezing sound.
C. Accumulation of fluid in the alveoli: Fluid in the alveoli, such as in pulmonary edema, typically produces crackles or rales during auscultation. Wheezing is specifically associated with the narrowing of the airway pipes, not the filling of the air sacs. The pathology of asthma focuses on the bronchial tubes.
D. Thickening of alveolar walls: Thickening of the alveolar-capillary membrane is characteristic of restrictive lung diseases like interstitial fibrosis. While it impairs gas exchange, it does not mechanically cause the expiratory wheezing seen in obstructive diseases like asthma. Asthma's primary defect is reversible airway obstruction and inflammation.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is C
Explanation
A. Enhanced respiratory muscle strength:Aging is characterized by sarcopenia, which involves the progressive atrophy of the diaphragm and intercostal muscles. This leads to a reduction in maximal inspiratory and expiratory pressures, making ventilation less efficient. Muscle strength typically declines rather than improves with advanced age.
B. Decreased vital capacity:As the thoracic cage becomes more rigid due to calcification of costal cartilages, the ability to fully expand the lungs diminishes. This structural change, combined with weakened musculature, reduces the maximum volume of air a person can exhale after a maximum inhalation. This is a standard finding in geriatric respiratory physiology.
C. Increased alveolar surface area:Senescence involves the breakdown of alveolar septa, resulting in fewer but larger air sacs, a process often termed senile emphysema. This reduces the total surface area available for gas exchange across the alveolar-capillary membrane. It impairs the efficiency of oxygen diffusion into the bloodstream.
D. Increased lung elasticity:Aging causes a loss of elastic recoil in the lung parenchyma due to changes in collagen and elastin fiber cross-linking. This loss of elasticity leads to early airway closure and increased residual volume. The lungs become more compliant but less able to recoil during expiration.
Correct Answer is D
Explanation
A. Avoid combining with antihistamines: Many allergy regimens safely combine decongestants for acute relief with antihistamines for long-term symptom control. There is no contraindication to using these two classes together to address different pathways of the allergic response. They provide additive benefits for the patient.
B. Take every 4 hours regardless of symptoms: Decongestants should be used sparingly and only when symptomatic to minimize systemic absorption and local irritation. Frequent, scheduled dosing increases the risk of side effects like tachycardia and hypertension. Using them on an "as-needed" basis is the safer clinical approach.
C. Discontinue as soon as symptoms resolve: While this is true for most symptomatic treatments, the specific instruction for decongestants must focus on the maximum duration of use. Even if symptoms persist, the patient must stop after 5 days to avoid rebound effects. The duration of therapy is more critical than the resolution of symptoms.
D. Use for no more than 3 to 5 days: Intranasal sympathomimetics provide rapid relief by constricting nasal blood vessels, but prolonged use leads to down-regulation of alpha-adrenergic receptors. This results in severe rebound vasodilation and mucosal edema when the drug is stopped. Limiting use prevents the development of rhinitis medicamentosa.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.