AHA PALS EXAM NEWEST 2025 ACTUAL EXAM
TEST BANK 230 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES
(VERIFIED ANSWERS) |ALREADY GRADED
A+||NEWEST VERSION
Lung compliance - ANSWER- • Compliance refers to the
distensibility of the lung, chest wall, or both. Specifically, lung
compliance is defined as the change in lung volume produced
by a change in driving pressure across the lung. When lung
compliance is high, the lungs easily inflate, a large change in
volume produced by a slight change in driving pressure.
• The lungs are stiffer in a child with low lung compliance, so it
takes more effort to inflate them. To create a significant
pressure gradient to produce air flow into the stiff lung, the
diaphragm contracts more forcefully, increasing intrathoracic
volume and reducing intrathoracic pressure. Poorly compliant
lungs will also lead to increased work of breathing. During
mechanical ventilation, increased positive airway pressure is
needed to achieve adequate ventilation when lung compliance
decreases.
,Decreased lung compliance - ANSWER- • The chest wall in
infants and young children is compliant. Therefore, relatively
small pressure changes can move the chest wall. During normal
breathing, diaphragm contraction in infants pulls the lower ribs
slightly inward but does not cause significant chest retraction.
However, forcefully contracting the diaphragm results in a large
drop in pressure within the chest, pulling the chest inward (ie,
retracting it) during inspiration.
• When lung compliance is reduced, maximum inspiratory
effort may not produce adequate tidal volume because marked
retractions of the chest wall limit lung expansion during
inspiration.
Breathing is controlled by complex mechanisms involving... -
ANSWER- • Brainstem respiratory centers
• Central and peripheral chemoreceptors
• Voluntary control
Respiratory center - ANSWER- A group of respiratory centers
located in the brainstem controls spontaneous breathing.
Voluntary control from the cerebral cortex, such as breath
holding, panting, and sighing, can also override breathing.
Conditions like infection of the central nervous system,
traumatic brain injury, and drug overdose can impair
respiratory drive, resulting in hypoventilation or even apnea.
,Chemoreceptors - ANSWER- Note that central chemoreceptors
respond to changes in the hydrogen ion concentration of
cerebrospinal fluid, which is largely determined by the arterial
CO2 tension (Paco,). Peripheral chemoreceptors (eg, the carotid
body) respond primarily to a decrease in arterial oxygen (Pa02);
some receptors also respond to an increase in Paco2
Healthcare providers often deliver excessive ventilation during
CPR, which is harmful because it... - ANSWER- • Increases
intrathoracic pressure and impedes venous return, thus
decreasing filling of the heart between compressions, reducing
blood flow generated by the next compression, and reducing
coronary perfusion and cerebral blood flow
• Causes air trapping and barotrauma in children with small
airway obstruction
• Increases the risk of regurgitation and aspiration in children
without an advanced airway
Awareness of Lung Compliance - ANSWER- • When performing
bag-mask ventilation, be aware of the child's lung compliance.
A poorly compliant lung is "stiff" or difficult to inflate. A sudden
increase in lung stiffness during ventilation with a bag may
indicate airway obstruction, decreased lung compliance, or
development of a pneumothorax.
, • Lung distention from excessive inflating pressures, positive
end-expiratory pressure, or rapid assisted respiratory rates with
short exhalation time may also cause the feel of "stiff lungs"
during ventilation.
Stomach inflation or distention frequently develops during bag-
mask ventilation. Gastric inflation is more likely to develop
during assisted ventilation if... - ANSWER- • A partial airway
obstruction is present
• High airway pressures are needed, such as in a child with poor
lung compliance
• The bag-mask ventilation rate is too fast
• The tidal volume delivered is excessive
• The peak inspiratory pressure created is excessive (eg, >30 cm
H20)
• The child is unconscious or is in cardiac arrest (because the
gastro-esophageal sphincter opens at a lower than normal
pressure)
To minimize gastric inflation - ANSWER- • Ventilate at a rate of 1
breath every 2 to 3 seconds (about 20-30 breaths per minute)
• Use a manometer (if available) and avoid, if at all possible,
generating excessive peak inspiratory pressures (eg, >30 cm
H20) by delivering each breath over about 1 second
TEST BANK 230 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES
(VERIFIED ANSWERS) |ALREADY GRADED
A+||NEWEST VERSION
Lung compliance - ANSWER- • Compliance refers to the
distensibility of the lung, chest wall, or both. Specifically, lung
compliance is defined as the change in lung volume produced
by a change in driving pressure across the lung. When lung
compliance is high, the lungs easily inflate, a large change in
volume produced by a slight change in driving pressure.
• The lungs are stiffer in a child with low lung compliance, so it
takes more effort to inflate them. To create a significant
pressure gradient to produce air flow into the stiff lung, the
diaphragm contracts more forcefully, increasing intrathoracic
volume and reducing intrathoracic pressure. Poorly compliant
lungs will also lead to increased work of breathing. During
mechanical ventilation, increased positive airway pressure is
needed to achieve adequate ventilation when lung compliance
decreases.
,Decreased lung compliance - ANSWER- • The chest wall in
infants and young children is compliant. Therefore, relatively
small pressure changes can move the chest wall. During normal
breathing, diaphragm contraction in infants pulls the lower ribs
slightly inward but does not cause significant chest retraction.
However, forcefully contracting the diaphragm results in a large
drop in pressure within the chest, pulling the chest inward (ie,
retracting it) during inspiration.
• When lung compliance is reduced, maximum inspiratory
effort may not produce adequate tidal volume because marked
retractions of the chest wall limit lung expansion during
inspiration.
Breathing is controlled by complex mechanisms involving... -
ANSWER- • Brainstem respiratory centers
• Central and peripheral chemoreceptors
• Voluntary control
Respiratory center - ANSWER- A group of respiratory centers
located in the brainstem controls spontaneous breathing.
Voluntary control from the cerebral cortex, such as breath
holding, panting, and sighing, can also override breathing.
Conditions like infection of the central nervous system,
traumatic brain injury, and drug overdose can impair
respiratory drive, resulting in hypoventilation or even apnea.
,Chemoreceptors - ANSWER- Note that central chemoreceptors
respond to changes in the hydrogen ion concentration of
cerebrospinal fluid, which is largely determined by the arterial
CO2 tension (Paco,). Peripheral chemoreceptors (eg, the carotid
body) respond primarily to a decrease in arterial oxygen (Pa02);
some receptors also respond to an increase in Paco2
Healthcare providers often deliver excessive ventilation during
CPR, which is harmful because it... - ANSWER- • Increases
intrathoracic pressure and impedes venous return, thus
decreasing filling of the heart between compressions, reducing
blood flow generated by the next compression, and reducing
coronary perfusion and cerebral blood flow
• Causes air trapping and barotrauma in children with small
airway obstruction
• Increases the risk of regurgitation and aspiration in children
without an advanced airway
Awareness of Lung Compliance - ANSWER- • When performing
bag-mask ventilation, be aware of the child's lung compliance.
A poorly compliant lung is "stiff" or difficult to inflate. A sudden
increase in lung stiffness during ventilation with a bag may
indicate airway obstruction, decreased lung compliance, or
development of a pneumothorax.
, • Lung distention from excessive inflating pressures, positive
end-expiratory pressure, or rapid assisted respiratory rates with
short exhalation time may also cause the feel of "stiff lungs"
during ventilation.
Stomach inflation or distention frequently develops during bag-
mask ventilation. Gastric inflation is more likely to develop
during assisted ventilation if... - ANSWER- • A partial airway
obstruction is present
• High airway pressures are needed, such as in a child with poor
lung compliance
• The bag-mask ventilation rate is too fast
• The tidal volume delivered is excessive
• The peak inspiratory pressure created is excessive (eg, >30 cm
H20)
• The child is unconscious or is in cardiac arrest (because the
gastro-esophageal sphincter opens at a lower than normal
pressure)
To minimize gastric inflation - ANSWER- • Ventilate at a rate of 1
breath every 2 to 3 seconds (about 20-30 breaths per minute)
• Use a manometer (if available) and avoid, if at all possible,
generating excessive peak inspiratory pressures (eg, >30 cm
H20) by delivering each breath over about 1 second
