PALS certification: Misunderstood concepts & exam tips

Following are the topics students misunderstand during their PALS test.

Bag valve mask (BVM) ventilation:

For emergency providers, bag valve mask (BVM) ventilation is a very important and crucial skill. This skill is not easy to attain, it requires deliberate practice to master it for being utilized in emergency situations. For making the process of BVM ventilation successful four things are important:

  • A patent airway
  • Proper BVM ventilation technique
  • To improve oxygenation required PEEP value
  • An adequate mask seal

To ensure a successful procedure, proper positioning of the patient is very important1. Bag valve mask ventilation can be carried out by one person, but two-person BVM ventilation is preferred. Two-person BVM ventilation is ideal, easier, and effective because achieving a tight seal requires two hands on the mask. During a two-person bag valve mask ventilation, maintaining a proper mask seal is a tricky task so that is why the more experienced operator handles the mask. The other one squeezes the bag2.

Monitor the efficacy of chest compressions:

In cardiac arrest, while performing CPR, the end-tidal CO2 (ETCO2) waveform shows an indirect measurement of blood flow generated by chest compressions. ETCO2 corresponds to the resuscitation rate and systemic blood flow during CPR and may possibly show chest compression efficacy3. During CPR the height of the ETCO2 waveform has been used by the resuscitators in monitoring the efficacy of compressions in real-time and as an indirect measure of normal chest compressions. Achieving ETCO2 pressures of a minimum of 10–20mmHg indicates high-quality chest compressions according to ACLS guidelines4. A study conducted in 1997 shows that ETCO2 less than 10mmHg for 20 minutes predicts non-survivability in out of hospital cardiac arrest patients leading to terminating resuscitation efforts. While medical professionals provide chest compressions ETCO2 helps them to determine if there is performer fatigue, or if they need to be deeper or any other factors that may hinder the ability to achieve and maintain ideal cardiac output. It defines ideal chest compressions more accurately than the visual estimation of compression depth. ETCO2 capnography aids in resuscitative efforts, it has the potential to predict whether the patient will not only survive but thrive.

Compensated and uncompensated shock:

The symptoms of compensated and uncompensated shock are never identical, also, if the shock is left unchecked and untreated it can be fatal. That is why it is crucial to treat the shock as early as possible before it reaches the irreversible phase. During a compensated shock the body maintains organ perfusion and blood pressure by elevating the cardiac rate and vasoconstriction even in a state of low blood volume. In an emergency situation the patient’s level of mental state, consciousness and other vital signs must be measured by proper patient assessment. As sometimes a patient is not frankly hypotensive so it becomes difficult to recognize the shock5. The symptoms may include agitation, restlessness, anxiety, nausea, or vomiting, rapid breathing, and narrow pulse pressure. In a non-compensated shock, the body is unable to maintain blood pressure and the perfusion of vital organs. The symptoms include reduced body temperature, falling blood pressure, irregular breathing, and dilated pupil6. In case of a non-compensated shock, it is sometimes crucial to request ACLS measures for the patient. While giving treatment priority should be given to treat the primary cause of the shock. A decrease in blood pressure often indicates late-stage shock. Rapid response is the key to successful shock treatment.

The jaw-thrust maneuver, but you are unable to maintain an open airway:

The jaw-thrust maneuver is a noninvasive, manual means that helps restore upper airway patency when the tongue occludes the glottis, which commonly occurs in an obtunded or unconscious patient. Using a jaw thrust maneuver an open airway can be established and maintained. This maneuver generates less cervical spine motion as compared to head tilt and chin lift methods7, while all three are effective maneuvers for opening the patient’s airway. However, chin lift and head tilt methods are easy to perform and maintain. If the jaw-thrust maneuver does not maintain open airway use head-tilt and chin-lift maneuvers. Failure in maintaining a patent airway can result in severe bradycardia, asystole, hypoxemia, as the demand for oxygen is high and the reserve is low8. Hypoxemia is a decreased level of oxygen in the blood, especially in arteries. Oxygen saturation in the blood is measured by using a pulse oximeter (a small device that clips to the finger of the patient). Values under 90% are considered low and indicate hypoxemia.


This page was last reviewed and updated by on Jun 10, 2021.