What is the normal length of a PR interval?
0.12 to 0.20 seconds
Define sinus bradycardia (rate and rhythm).
Regular rhythm, rate <60 bpm, normal P waves, PR, and QRS
Define sinus tachycardia (rate and rhythm).
Regular rhythm, rate 101–150 bpm, normal P waves, PR, and QRS
Which drug is first-line for ventricular fibrillation?
Epinephrine
True or False: A UAP can place defibrillator pads on a patient.
True
Which part of the conduction system is considered the “pacemaker” of the heart?
Sinoatrial (SA) node
What drug is first-line treatment for symptomatic sinus bradycardia?
IV Atropine 1 mg every 3–5 min (max 3 mg)
What is the first-line vagal maneuver for stable SVT?
Valsalva maneuver
What dose and frequency of epinephrine is used in cardiac arrest?
1 mg IV/IO every 3–5 minutes
Which tasks can be delegated to a UAP for a patient with sinus bradycardia who is asymptomatic?
Obtain vital signs, apply oxygen, place monitor leads; RN interprets rhythm and manages treatment
A QRS complex wider than ___ seconds is considered abnormal.
>0.12 seconds
In second-degree type I AV block, what happens to the PR interval before a dropped QRS?
PR interval progressively lengthens until a beat is dropped
Which medication is given rapidly (with a fast IV push and flush) for SVT?
First dose: 6 mg rapid IV push; follow with 20 mL NS flush.
Second dose: 12 mg if required; follow with 20 mL NS flush.
What antiarrhythmic drug can be used if amiodarone is unavailable during VF/VT arrest?
Lidocaine
During a code, what is the respiratory therapist’s primary role?
Manage airway and ventilation (bag-mask, advanced airway placement)
What is the hallmark EKG finding of atrial fibrillation?
Irregularly irregular rhythm with absent P waves (fibrillatory waves)
A patient with complete heart block becomes unresponsive and pulseless. What is your immediate action?
Start CPR and follow ACLS cardiac arrest algorithm (not bradycardia algorithm)
A patient with atrial fibrillation with RVR is unstable (hypotension, chest pain). What is the priority treatment?
Immediate synchronized cardioversion
Which drug is used to treat polymorphic VT (torsades de pointes)?
IV Magnesium sulfate
Which tasks must remain the responsibility of the RN during ACLS?
Rhythm interpretation, medication administration, defibrillation/cardioversion, leadership/decision-making
Describe the difference between monomorphic and polymorphic ventricular tachycardia.
Monomorphic = QRS complexes uniform in shape/size; Polymorphic = QRS complexes vary in shape/size (e.g., torsades de pointes)
Which ACLS drugs can be used as an infusion when atropine is ineffective for bradycardia?
Dopamine infusion or Epinephrine infusion
What is the difference in treatment between stable VT with a pulse and pulseless VT?
Stable VT with a pulse: Amiodarone, synchronized cardioversion if needed
Pulseless VT: CPR, defibrillation, epinephrine, amiodarone
List the reversible causes (Hs & Ts) that should always be considered during cardiac arrest.
Hs: Hypovolemia, Hypoxia, Hydrogen ion (acidosis), Hypo-/hyperkalemia, Hypothermia
Ts: Tension pneumothorax, Tamponade (cardiac), Toxins, Thrombosis (coronary or pulmonary)
A patient is found unresponsive, pulseless, and in ventricular fibrillation. Walk through the ACLS algorithm for the first 2 cycles, including drugs, interventions, and defibrillation timing.
Start CPR, attach monitor/defibrillator
Defibrillate immediately
Resume CPR for 2 min
Give Epinephrine 1 mg IV/IO every 3–5 min (after second shock)
Defibrillate again, resume CPR
Consider Amiodarone 300 mg IVP, then 150 mg if VF/pulseless VT persists
Continue cycles with CPR, defibrillation every 2 min, and alternating drugs
Always consider Hs & Ts