Pediatric Respiratory: Midterm Exam (Units 1-7) - Questions
with Correct Answers
100 questions
1. Compared with an adult, a child's functional residual capacity relative to oxygen demand is:
A. Larger, so desaturation is delayed
B. Smaller, so oxygen reserve is limited
C. Identical
D. Unrelated to desaturation
Correct Answer: B. Smaller, so oxygen reserve is limited
Rationale: A small functional residual capacity combined with high oxygen consumption means
children have little reserve and desaturate quickly. Larger or identical reserves would delay
desaturation, which is not the case.
2. Children have fewer and smaller alveoli than adults, and alveolar development continues until
about:
A. Birth, with no further growth
B. Early childhood to adolescence, with most growth in the first years
C. Six weeks after birth
D. Age 40
Correct Answer: B. Early childhood to adolescence, with most growth in the first years
Rationale: Alveoli multiply rapidly after birth and continue to develop through childhood, which
is why early lung injury or smoke exposure can have lasting effects. Lung growth does not stop
at birth or at six weeks, and it is complete well before adulthood ends.
,3. Breath sounds in infants can be difficult to localize because:
A. Infants have no bronchial sounds
B. Stethoscopes cannot be used on infants
C. The thin chest wall transmits sounds widely, including upper airway noises
D. Infant lungs are silent
Correct Answer: C. The thin chest wall transmits sounds widely, including upper airway noises
Rationale: The thin chest transmits sounds from the nose and throat and from one side to the
other, so sounds may be heard throughout. Clearing the nose and comparing sides helps
interpretation. Infants have audible lung sounds that can be assessed with a pediatric
stethoscope.
4. Retractions are seen more easily in infants than in adults mainly because:
A. The infant chest wall is soft and compliant and is pulled inward with increased effort
B. Infants have more intercostal muscle
C. Infant lungs are stiffer than the chest wall in health
D. Infants breathe only with accessory muscles
Correct Answer: A. The infant chest wall is soft and compliant and is pulled inward with
increased effort
Rationale: A cartilaginous, compliant chest wall is drawn inward when the child generates high
negative pressure to move air. Infants have weaker intercostal muscles, healthy infant lungs are
not stiffer than the chest wall, and they rely mainly on the diaphragm.
5. A barking, seal-like cough in a young child most often suggests:
A. Pneumonia
B. Allergic rhinitis
C. Cystic fibrosis
D. Subglottic inflammation, as in croup
Correct Answer: D. Subglottic inflammation, as in croup
Rationale: Swelling below the vocal cords produces the characteristic bark of croup. Pneumonia
usually produces a wet or productive cough, allergic rhinitis a throat-clearing cough, and cystic
fibrosis a chronic wet cough.
,6. An arterial blood gas of pH 7.28, PaCO2 58 mm Hg and HCO3 24 mEq/L in a child with asthma
indicates:
A. Metabolic alkalosis
B. Compensated metabolic acidosis
C. Uncompensated respiratory acidosis
D. Normal values
Correct Answer: C. Uncompensated respiratory acidosis
Rationale: The low pH with high carbon dioxide and normal bicarbonate shows acute
respiratory acidosis without renal compensation, a worrying finding in asthma. The values do
not match metabolic alkalosis or metabolic acidosis, and they are not normal.
7. Compared with an adult, a small amount of airway edema causes a much greater increase in
airway resistance in an infant because:
A. Infant airways are lined with thicker cartilage
B. Infants have a larger tongue-to-airway ratio only in sleep
C. Resistance rises sharply as the radius of a small airway decreases
D. Infant airways contain fewer goblet cells
Correct Answer: C. Resistance rises sharply as the radius of a small airway decreases
Rationale: Resistance is inversely related to the radius to the fourth power, so 1 mm of edema
in a narrow infant airway dramatically increases work of breathing. Cartilage in infants is softer,
not thicker. Tongue size and goblet cells do not explain the effect of edema.
8. Capillary refill in a child with respiratory illness helps the nurse assess:
A. Lung compliance
B. Airway diameter
C. Oxygen saturation directly
D. Peripheral perfusion, which may be poor in dehydration or shock
Correct Answer: D. Peripheral perfusion, which may be poor in dehydration or shock
Rationale: A refill time longer than about 2 seconds suggests poor perfusion from dehydration
or shock, which may accompany severe respiratory illness. It does not measure lung
compliance, airway size or saturation.
, 9. A generally acceptable target oxygen saturation for most children with acute respiratory
illness and no heart disease is:
A. At least 100 percent at all times
B. About 80 percent
C. About 85 percent
D. About 90 to 92 percent or higher
Correct Answer: D. About 90 to 92 percent or higher
Rationale: Many pediatric guidelines accept saturations of about 90 to 92 percent or higher in
acute illness, avoiding unnecessary oxygen. A target of 100 percent is unnecessary and may
prolong admission, while 80 to 85 percent reflects significant hypoxemia.
10. An infant with a respiratory rate of 75 breaths per minute is being bottle-fed. The nurse
should be concerned because:
A. Rapid breathing raises the risk of aspiration during feeding
B. Feeding always slows breathing
C. Tachypnea improves sucking coordination
D. Formula reduces respiratory effort
Correct Answer: A. Rapid breathing raises the risk of aspiration during feeding
Rationale: Infants must coordinate sucking, swallowing and breathing, and very fast breathing
makes aspiration more likely, so oral feeding may be held or modified per orders. Feeding does
not slow breathing, tachypnea impairs rather than improves coordination, and formula does
not lessen effort.
with Correct Answers
100 questions
1. Compared with an adult, a child's functional residual capacity relative to oxygen demand is:
A. Larger, so desaturation is delayed
B. Smaller, so oxygen reserve is limited
C. Identical
D. Unrelated to desaturation
Correct Answer: B. Smaller, so oxygen reserve is limited
Rationale: A small functional residual capacity combined with high oxygen consumption means
children have little reserve and desaturate quickly. Larger or identical reserves would delay
desaturation, which is not the case.
2. Children have fewer and smaller alveoli than adults, and alveolar development continues until
about:
A. Birth, with no further growth
B. Early childhood to adolescence, with most growth in the first years
C. Six weeks after birth
D. Age 40
Correct Answer: B. Early childhood to adolescence, with most growth in the first years
Rationale: Alveoli multiply rapidly after birth and continue to develop through childhood, which
is why early lung injury or smoke exposure can have lasting effects. Lung growth does not stop
at birth or at six weeks, and it is complete well before adulthood ends.
,3. Breath sounds in infants can be difficult to localize because:
A. Infants have no bronchial sounds
B. Stethoscopes cannot be used on infants
C. The thin chest wall transmits sounds widely, including upper airway noises
D. Infant lungs are silent
Correct Answer: C. The thin chest wall transmits sounds widely, including upper airway noises
Rationale: The thin chest transmits sounds from the nose and throat and from one side to the
other, so sounds may be heard throughout. Clearing the nose and comparing sides helps
interpretation. Infants have audible lung sounds that can be assessed with a pediatric
stethoscope.
4. Retractions are seen more easily in infants than in adults mainly because:
A. The infant chest wall is soft and compliant and is pulled inward with increased effort
B. Infants have more intercostal muscle
C. Infant lungs are stiffer than the chest wall in health
D. Infants breathe only with accessory muscles
Correct Answer: A. The infant chest wall is soft and compliant and is pulled inward with
increased effort
Rationale: A cartilaginous, compliant chest wall is drawn inward when the child generates high
negative pressure to move air. Infants have weaker intercostal muscles, healthy infant lungs are
not stiffer than the chest wall, and they rely mainly on the diaphragm.
5. A barking, seal-like cough in a young child most often suggests:
A. Pneumonia
B. Allergic rhinitis
C. Cystic fibrosis
D. Subglottic inflammation, as in croup
Correct Answer: D. Subglottic inflammation, as in croup
Rationale: Swelling below the vocal cords produces the characteristic bark of croup. Pneumonia
usually produces a wet or productive cough, allergic rhinitis a throat-clearing cough, and cystic
fibrosis a chronic wet cough.
,6. An arterial blood gas of pH 7.28, PaCO2 58 mm Hg and HCO3 24 mEq/L in a child with asthma
indicates:
A. Metabolic alkalosis
B. Compensated metabolic acidosis
C. Uncompensated respiratory acidosis
D. Normal values
Correct Answer: C. Uncompensated respiratory acidosis
Rationale: The low pH with high carbon dioxide and normal bicarbonate shows acute
respiratory acidosis without renal compensation, a worrying finding in asthma. The values do
not match metabolic alkalosis or metabolic acidosis, and they are not normal.
7. Compared with an adult, a small amount of airway edema causes a much greater increase in
airway resistance in an infant because:
A. Infant airways are lined with thicker cartilage
B. Infants have a larger tongue-to-airway ratio only in sleep
C. Resistance rises sharply as the radius of a small airway decreases
D. Infant airways contain fewer goblet cells
Correct Answer: C. Resistance rises sharply as the radius of a small airway decreases
Rationale: Resistance is inversely related to the radius to the fourth power, so 1 mm of edema
in a narrow infant airway dramatically increases work of breathing. Cartilage in infants is softer,
not thicker. Tongue size and goblet cells do not explain the effect of edema.
8. Capillary refill in a child with respiratory illness helps the nurse assess:
A. Lung compliance
B. Airway diameter
C. Oxygen saturation directly
D. Peripheral perfusion, which may be poor in dehydration or shock
Correct Answer: D. Peripheral perfusion, which may be poor in dehydration or shock
Rationale: A refill time longer than about 2 seconds suggests poor perfusion from dehydration
or shock, which may accompany severe respiratory illness. It does not measure lung
compliance, airway size or saturation.
, 9. A generally acceptable target oxygen saturation for most children with acute respiratory
illness and no heart disease is:
A. At least 100 percent at all times
B. About 80 percent
C. About 85 percent
D. About 90 to 92 percent or higher
Correct Answer: D. About 90 to 92 percent or higher
Rationale: Many pediatric guidelines accept saturations of about 90 to 92 percent or higher in
acute illness, avoiding unnecessary oxygen. A target of 100 percent is unnecessary and may
prolong admission, while 80 to 85 percent reflects significant hypoxemia.
10. An infant with a respiratory rate of 75 breaths per minute is being bottle-fed. The nurse
should be concerned because:
A. Rapid breathing raises the risk of aspiration during feeding
B. Feeding always slows breathing
C. Tachypnea improves sucking coordination
D. Formula reduces respiratory effort
Correct Answer: A. Rapid breathing raises the risk of aspiration during feeding
Rationale: Infants must coordinate sucking, swallowing and breathing, and very fast breathing
makes aspiration more likely, so oral feeding may be held or modified per orders. Feeding does
not slow breathing, tachypnea impairs rather than improves coordination, and formula does
not lessen effort.
