ATI LPN
Introduction of Respiratory System NCLEX Questions PN Questions
Question 1 of 5
The primary chemical stimulus for breathing is the concentration of
Correct Answer: B
Rationale: Carbon dioxide (CO₂) in the blood is the primary breathing stimulus, detected by central chemoreceptors in the medulla as H+ ions rise (from CO₂ forming carbonic acid, H₂CO₃). Elevated CO₂ (hypercapnia) increases ventilation to expel it, maintaining pH. Oxygen (O₂) influences peripheral chemoreceptors but is secondary low O₂ (hypoxia) only drives breathing if severe. Carbon monoxide binds hemoglobin but isn't a stimulus. Carbonic acid reflects CO₂ indirectly, not directly measured. CO₂'s dominance, via brainstem response, ensures homeostasis, key in respiratory control and disorders like apnea where CO₂ sensing falters.
Question 2 of 5
A client with acute asthma showing inspiratory and expiratory wheezes and a decreased expiratory volume should be treated with which of the following classes of medication right away?
Correct Answer: B
Rationale: Bronchodilators (B), like albuterol, are the first-line treatment for acute asthma with wheezes and reduced expiratory volume. They rapidly relax bronchial smooth muscle, reversing bronchoconstriction the root of airflow limitation easing wheezing and dyspnea. Beta-blockers (A) worsen asthma, causing constriction. Inhaled (C) or oral steroids (D) reduce inflammation but act slowly, unsuitable for immediate relief used adjunctively. Wheezing reflects narrowed airways; bronchodilators open them fast, critical in acute settings to prevent hypoxia, a nursing priority over slower anti-inflammatory options.
Question 3 of 5
A 45-year-old man has smoked two packs of cigarettes per day for 20 years. For the past 4 years, he has had chronic cough with copious mucoid expectoration. During the past year, he has had multiple respiratory tract infections diagnosed as 'viral flu'. He has also developed difficulty breathing, tightness of the chest, and audible wheezing. His breathing difficulty is relieved by inhalation of B-adrenergic agonist and disappears after the chest infection has resolved. Which of the following pathologic conditions is most likely responsible for his clinical condition?
Correct Answer: C
Rationale: Chronic asthmatic bronchitis (C) fits this smoker's profile (Page 28, Ans: C). Chronic bronchitis (cough >3 months, 2 years) from smoking (40 pack-years) plus nonatopic asthma (wheezing, B-agonist relief) post-viral infections explains symptoms . AAT deficiency (A) causes panacinar emphysema, no bronchoconstriction. Centriacinar emphysema (B) lacks wheezing prominence. Cystic fibrosis (D) starts in childhood, not midlife. C's dual pathology mucus hypersecretion (100 mL/day) and hyperreactivity distinguishes it from A's genetic basis or B's pure obstruction, per document.
Question 4 of 5
A 70-year-old woman has had episodes of dyspnea with wheezing and coughing, accompanied by urticaria for the past 3 years. She has had bouts of rhinitis. She has a 10-year history of osteoarthritis. On physical examination she has nasal polyps. Use of which of the following medications is the most likely risk factor for her respiratory disease?
Correct Answer: B
Rationale: Aspirin (B) triggers intrinsic asthma here (Page 30, Ans: B). Blocking cyclooxygenase shunts arachidonic acid to leukotrienes (Page 5), causing bronchospasm and rhinitis. Acetaminophen (A) is safe. Gabapentin (C) and morphine (D) are unrelated. B's effect 10% incidence contrasts A's neutrality, per document.
Question 5 of 5
A 28 year old woman with cystic fibrosis presents with increasing shortness of breath and production of abundant foul-smelling sputum. The sputum in this patient is most likely associated with which of the following pulmonary condition?
Correct Answer: B
Rationale: Bronchiectasis (B) links to cystic fibrosis sputum . CFTR mutation thickens mucus , dilating bronchi (100 mL/day). Atelectasis (A) collapses. Emphysema (C) is dry. Pneumothorax (D) lacks sputum. B's infection unlike C's dryness is typical, per document.