ATI LPN
Respiratory System Questions Questions
Question 1 of 5
The valve that guards the left atrioventricular orifice is called the:
Correct Answer: D
Rationale: The left atrioventricular valve is called both bicuspid (two cusps) and mitral (mitre-shaped), guarding the left atrium-ventricle junction, preventing backflow. Tricuspid is right-sided. This dual naming reflects its structure and role, key in mitral pathology like prolapse, a synonymous valve identity in heart flow.
Question 2 of 5
The nurse assisting the client with obstructive pulmonary disease would use which of the following statements to explain why dyspnea occurs?
Correct Answer: C
Rationale: Your airways open wider on inspiration, and trap air on expiration' (C) explains COPD dyspnea, per document (3). Emphysema's elasticity loss (elastase > AAT) and chronic bronchitis's mucus narrow airways, trapping air (RV >150%), reducing tidal volume (Vt <400 mL). Surfactant (A) is ARDS, not COPD. Difficulty inhaling (B) is vague. Compliance drop (D) fits fibrosis. C's air trapping FEVâ‚/FVC <70% drives dyspnea, unlike A's irrelevance.
Question 3 of 5
The parents of a child with bronchopulmonary dysplasia (BPD) are receiving home instructions on tracheotomy care. With regards to suctioning, the nurse should advise the parents that each suction pass should take no longer than:
Correct Answer: B
Rationale: 5 seconds (B) is the advised suction time for BPD tracheotomy, per document (implied pediatric norm). Short passes (5-10 s) clear mucus (e.g., 5-10 mL) without hypoxia (SpOâ‚‚ drop <5%). 2 seconds (A) is too brief, 10-15 seconds (C, D) risk desaturation. B's balance per AAP protects fragile BPD lungs (Oâ‚‚ need 30%), unlike D's excess.
Question 4 of 5
Surface tension of the alveolar fluid is reduced by the presence of
Correct Answer: C
Rationale: Surfactant, a lipoprotein mix from type II alveolar cells, reduces alveolar fluid's surface tension, preventing collapse (atelectasis) by lowering cohesive forces of water molecules lining alveoli. Mucus traps particles in airways, not affecting alveolar tension. Sebum, an oily skin secretion, is irrelevant here. Water increases tension surfactant counters this. By decreasing tension, surfactant stabilizes alveoli, especially smaller ones, easing inflation and preventing lung collapse post-exhalation. This is vital for efficient gas exchange, a cornerstone of lung mechanics, critical in conditions like respiratory distress syndrome where surfactant deficiency causes breathing difficulty, underscoring its role in pulmonary stability.
Question 5 of 5
Most oxygen in the blood is transported
Correct Answer: B
Rationale: Most oxygen (~98%) is transported as oxyhemoglobin, bound to hemoglobin in red blood cells, each molecule carrying four Oâ‚‚ vastly more than dissolved in plasma (~2%, ~0.3 mL/100 mL). Carboxyhemoglobin forms with carbon monoxide, not Oâ‚‚ transport. Bicarbonate (HCO₃â») carries COâ‚‚, not Oâ‚‚. Oxyhemoglobin's high capacity, shifting with POâ‚‚ (oxygen-hemoglobin curve), ensures efficient Oâ‚‚ delivery to tissues, key in oxygen transport physiology, critical in anemia or hypoxia where binding capacity or Oâ‚‚ levels drop, impacting cellular supply.