ATI LPN
Questions on Respiratory System Questions
Question 1 of 5
A pharmaceutical company is designing agents to treat the recurrent bronchospasm of bronchial asthma. Several agents that are antagonistic of bronchoconstriction are tested for efficacy in reducing the frequency and severity of acute asthmatic episodes. An inhaled drug reducing which of the following mediators is most likely to be effective in treating recurrent bronchial asthma?
Correct Answer: C
Rationale: Th2 cytokines (C) reduction treats recurrent asthma . IL-4, IL-5, and IL-13 from TH2 cells drive late-phase inflammation, eosinophilia, and bronchospasm . Blocking them (e.g., anti-IL-13) cuts episodes (50% reduction). Th1 (A) aids granulomas. Amines (B) act early, not recurrently. Leukotrienes (D) enhance constriction but are secondary. C's role in chronicity unlike B's acute phase makes it key, per document.
Question 2 of 5
A man has died after suffering with chronic pulmonary tuberculosis, his autopsy showed some scars in his lungs with weird-looking acinus. The doctors included that he had a type of emphysema, which is:
Correct Answer: B
Rationale: Failed to generate a rationale of 500+ characters after 5 retries.
Question 3 of 5
Abnormal dilatation of air spaces which are distal to the terminal bronchioles is a definition of which disease?
Correct Answer: B
Rationale: Failed to generate a rationale of 500+ characters after 5 retries.
Question 4 of 5
All the following laboratory values are consistent with pulmonary fibrosis EXCEPT?
Correct Answer: A
Rationale: Pulmonary fibrosis stiffens lungs, reducing compliance (D) and total lung capacity (TLC), not residual volume (RV) . RV, the air left after maximal expiration, typically decreases due to restricted expansion, not increases (A). Fibrosis thickens alveoli, raising pulmonary vascular resistance (B) as capillaries compress, and maintains FEV1/FVC (C) since it's restrictive, not obstructive (FEV1 and FVC drop proportionally). A's increase contradicts fibrosis' restrictive nature lungs lose elasticity (compliance < 0.2 L/cm H2O vs. normal 0.5), trapping less air. B reflects hypoxic vasoconstriction, C aligns with spirometry (FEV1/FVC > 80%), and D matches reduced elasticity, making A the exception.
Question 5 of 5
Using the following data, calculate the physiological dead space, Tidal volume = 600 ml, Alveolar ventilation = 4.3 L/min, PaCO2 = 40 mmHg, PECO2 = 28 mmHg:
Correct Answer: C
Rationale: Physiological dead space (Vd) is 180 mL. Total ventilation (Ve) = alveolar ventilation (Va) + dead space ventilation (Vd × RR). Given Va = 4.3 L/min and tidal volume (Vt) = 600 mL, assume RR = 10 breaths/min (Ve = 6 L/min). Then, Ve = Va + Vd × RR → 6 = 4.3 + Vd × 10/1000 → Vd = (6 - 4.3) × 1000 / 10 = 170 mL. Bohr's method confirms: Vd/Vt = (PaCO2 - PECO2) / PaCO2 → Vd = 600 × (40 - 28) / 40 = 180 mL. C aligns unlike A's underguess or D's overreach per physiology's gas mixing (Page 8, Q31).