Cardiovascular Critical Care II

Answer: B

Because rescuer fatigue is common and may lead to

inadequate compression quality, it is recommended to

change rescuers every 2 minutes, with no more than

5 seconds between changes (Answer A is incorrect).

Compressions are vital because they increase intratho-

racic pressure and directly compress the heart, leading

to oxygen delivery to the vital organs (Answer B is cor-

rect). Specific aspects of chest compression quality are

necessary. These include a rate of 100–120 compres-

sions per minute at a depth of 2–2.4 inches in adults,

allowing for recoil after each compression; placement

of the patient on a hard surface (e.g., backboard); and

minimization of interruptions (Answer C is incorrect).

Outcomes, including neurologically intact survival,

ROSC, and possibly overall survival, are linked to mini-

mizing interruptions in chest compressions. Because of

this, it is recommended that interruptions (e.g., pulse

checks and intubation) be less than 10 seconds and that

chest compressions be resumed immediately (Answer D

is incorrect).

Cardiac arrest patients have minimal blood flow, and

oxygenation/ventilation requirements are lower; the new

recommendation is to provide 1 breath every 5–6 sec-

onds (10–12 breaths/minute) until an advanced airway

is in place (Answer C is correct). Although the optimal

ratio is unclear and chest compressions appear to be

more vital to resuscitation, other ratios cannot currently

be recommended (Answer A is incorrect). It is clear,

however, that excessive ventilation can lead to decreased

venous return and gastric inflation, which can lead to

aspiration, regurgitation, and impacts on outcomes. In

this case, a bag-mask ventilator is available, and more

than one rescuers are involved, so the bag-mask venti-

lator should be used (Answer B is incorrect). In single

health care provider rescuer situations, the bag-mask

ventilator should never be used, and mouth-to-mouth

or mouth-to-barrier resuscitation is recommended. In

a single nonmedical rescuer situation, hands-only CPR

is recommended. Advanced airways can be considered

but should be placed only by experienced and trained

personnel. Bag-mask ventilation can provide adequate

oxygenation/ventilation until an airway can be secured

(Answer D is incorrect).

Answer: A

Three vital actions with VF aid in survival: call emer-

gency response team (already accomplished in case),

begin CPR (must be initiated in case), and deliver shock

(must occur in case) (Answer A is correct). Pacing can

be effective in overriding stable VT but should not be

used in the cardiac arrest or hemodynamically unstable

patient (Answer B is incorrect). It is currently unclear

whether postponing defibrillation for the provision of

chest compressions first is of benefit, but it is clear that

chest compressions should be initiated until the defi-

brillator is ready, charged, and set to deliver the shock

because this increases the likelihood of success with

defibrillation (Answer C is incorrect). Because time in

VF predicts survival, and the longer patients are in VF

the more difficult it is to terminate the arrhythmia, alter-

native treatments such as medications should not impede

the provision of defibrillation (Answer D is incorrect).

Answer: D

After the advanced airway is in place, it is crucial to

confirm placement in order to provide the intended oxy-

genation/ventilation. The confirmation should occur

with both clinical and objective measurements (Answer

D is correct). These include a physical assessment of the

chest and epigastrium, end-tidal CO2 monitoring, and/

or continuous waveform capnography. In most cardiac

arrests (particularly in this patient’s pVT), airway man-

agement should not impede the provision of CPR and/or

defibrillation (when defibrillation is indicated) (Answer

B is incorrect). After the advanced airway is in place,

100% oxygen should be delivered to optimize the arterial

oxygen saturation (Answer C is incorrect). In the car-

diac arrest population, this has not been shown to carry

the same toxicity as in other populations. Furthermore,

after advanced airway is placed, compressions should be

administered at a rate of 100–120 compressions per min-

ute continuously, with breaths every 6 seconds (Answer

A is incorrect).

Answer: B

In all cardiac arrests, the treatable causes (i.e., H’s

and T’s) should be reviewed and addressed, if possible

(Answer B is correct). In patients for whom the labo-

ratory and diagnostic data are known, the information

should be reviewed while CPR is being provided. In