Key Terms
This is the informal term to describe the delivery of electrical energy to the patient's heart, such as during defibrillation.
Shock
An electrical impulse that "escapes" from a site other than the sinoatrial node and causes ventricular depolarization.
Escape Beat
An escape beat may originate from what three areas?
The atria, the AV junction, the ventricles.
An aberrantly conducted complex occurs when:
In a PEA, there will be no contraction of the _______.
This technique delivers an electrical current to the heart to correct ventricular fibrillation (VF) and pulseless ventricular tachycardia (PVT).
Defibrillation
The ability of the cardiac muscle cells to respond to electrical impulses generated by an artificial pacemaker.
Atrial Escape Beats originate from anywhere in the atria, except the ______ ______.
SA Node
True/False: An aberrantly conducted complex may have a negative QRS complex when the underlying rhythm has a positive QRS complex.
True.
In a PEA, the rhythm seen on the monitor screen or rhythm strip will most likely be:
bradycardic, with wide or narrow QRS complexes
A small, battery operated device that initiates electrical impulses in the heart; it may be temporary or permanent.
Artificial pacemaker
A device that determines the patient's cardiac rhythm and defibrillates the heart, if necessary.
Automated External Defibrillator (AED)
If the SA node and atria fail to generate an electrical impulse or if the impulse is not conducted, the AV junctional area can generate the impulse. This impulse is called what?
Junctional Escape Beat
Why do aberrantly conducted complexes appear different than the complexes in the underlying rhythm?
Because they do not follow the same electrical conduction pathway.
True/False: PEA is lethal.
True
The procedure used to initiate ventricular depolarization through the use of an artificial pacemaker.
Pacing
What might you see when complex formations are seen on the a monitor, but the heart muscle is not contracting.
Pulseless Electrical Activity (PEA)
An escape beat can remain a single complex, or it can progress into an escape rhythm. Name two examples of an escape rhythm.
Junctional Tachycardia, Idioventricular Dysrhythmias
Aberrantly conducted complexes can originate in what three areas?
Anywhere in the atria, in the AV junction, in the ventricles
PEA can be caused by four things. List them.
Hypovolemia
Hypoxia
Cardiac Tamponade
Tension Pneumothorax
What is the informal term for complexes that do not follow the usual patterns?
This is when there is blood or extra fluid in the pericardial sac, resulting in the heart's inability to pump blood.
Cardiac Tamponade
What is the purpose of an escape beat?
It is one way that the heart attempts to maintain a normal rate/rhythm.
Because aberrantly conducted complexes may have a wide QRS complex, it can be difficult to distinguish them from a ______ ______ ______.
Describe hypovolemia, hypoxia, cardiac tamponade and tension pneumothorax.
Hypovolemia: loss of blood volume.
Hypoxia: decrease in oxygen.
Cardiac Tamponade: blood or excess fluid in the pericardial sac.
Tension Pneumothorax: air in the pleural cavity that prevents one lung from expanding.