The nurse explained how to position an infant with tetralogy of Fallot if the infant suddenly becomes cyanotic. The nurse can determine the father understood the instructions when he states 'If the baby turns blue, I will:

Correct Answer: D

Rationale: Knee-chest position (D) relieves cyanotic spells in tetralogy of Fallot by increasing systemic resistance. Other positions (A, B, C) are ineffective. Document: 'The infant should be placed in a knee-chest position.'

Correct Answer: C

Rationale: A 10-year-old with lobar pneumonia and a history of cefaclor reaction (rash, target lesions, arthralgia) and familial penicillin anaphylaxis requires a safe antibiotic. Clindamycin (Choice C) is appropriate for community-acquired pneumonia, covering Streptococcus pneumoniae and some atypicals, and avoids beta-lactam cross-reactivity risks from her cephalosporin reaction and penicillin family history. Ceftriaxone (Choice A) and penicillin (Choice D), as beta-lactams, risk allergic reactions. Ciprofloxacin (Choice B) is less preferred in children due to side effects and atypical coverage focus. Clindamycin is the safest, effective choice.

Correct Answer: D

Rationale: Physiologic dead space is the lung volume not participating in CO2 elimination, including anatomic dead space plus alveolar dead space from non-perfused alveoli. Anatomic dead space (Choice A) is part but incomplete. Expiratory reserve capacity (Choice B) is functional volume. FEV1 (Choice C) and FVC (Choice D) measure flow and capacity, not dead space. Physiologic dead space is the full answer.

Correct Answer: D

Rationale: The third hepatitis B dose is recommended at 6 months , per CDC, ensuring full immunity. Earlier doses (A-D) are part of the schedule but not the final one.

Correct Answer: B

Rationale: Infantile hypertrophic pyloric stenosis fits, with erythromycin increasing risk via pyloric hypertrophy (AAP). Nonbilious vomiting rules out atresia , and A, B, D are less likely.