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The Global Insight

What are the Hs and Ts of ACLS

Author

Ava Hudson

Updated on April 15, 2026

Rapidly identify and treat causes of non-shockable arrest (PEA, asystole). Important causes include the 5 H’s and 5 T’s: Hypoxia, Hypovolemia, Hydrogen ions (acidosis), Hyper/Hypo-kalemia, Hypothermia; Tension pneumothorax, Tamponade-cardiac, Toxins, Thrombosis-coronary (MI), Thrombosis-pulmonary (PE).

What are the 5 H's and T's?

  • Hypovolemia.
  • Hypoxia.
  • Hydrogen ion excess (acidosis)
  • Hypoglycemia.
  • Hypokalemia.
  • Hyperkalemia.
  • Hypothermia.
  • Tension pneumothorax.

What is Pea in ACLS?

Pulseless electrical activity (PEA) and asystole are related cardiac rhythms in that they are both life-threatening and unshockable cardiac rhythms.

What are the 4 Hs and 4 Ts?

However, in practice while performing CPR often in stressful situations, it is difficult to remember all 4 “Ts” and 4 “Hs” causes (hypoxia, hypokalaemia/hyperkalaemia, hypothermia/hyperthermia, hypovolaemia, tension pneumothorax, tamponade, thrombosis, toxins), especially for medical students, young doctors and doctors …

How do you ace ACLS?

  1. Review ACLS Case Scenarios. …
  2. Memorize the ACLS Algorithms. …
  3. Memorize Meds and Proper Dosages. …
  4. Know Your H’s and T’s. …
  5. Understand Basic Electrocardiography. …
  6. Take Multiple Practice Exams. …
  7. Skip the Hard Questions at First. …
  8. Take Your Time.

What does AED stand for?

Automated external defibrillators (AEDs) are portable, life-saving devices designed to treat people experiencing sudden cardiac arrest, a medical condition in which the heart stops beating suddenly and unexpectedly.

What are the 5 H's and 5 T's of ACLS?

Rapidly identify and treat causes of non-shockable arrest (PEA, asystole). Important causes include the 5 H’s and 5 T’s: Hypoxia, Hypovolemia, Hydrogen ions (acidosis), Hyper/Hypo-kalemia, Hypothermia; Tension pneumothorax, Tamponade-cardiac, Toxins, Thrombosis-coronary (MI), Thrombosis-pulmonary (PE).

Why do you not shock asystole?

Pulseless electrical activity and asystole or flatlining (3 and 4), in contrast, are non-shockable, so they don’t respond to defibrillation. These rhythms indicate that the heart muscle itself is dysfunctional; it has stopped listening to the orders to contract.

Which is one of the H's and T's that represent a potentially reversible cause?

Treating the cause of hypoxia/hypoxemia must be done quickly because this is one of the potentially reversible causes of cardiac arrest. Proper oxygenation and ventilation are key to restoring adequate amounts of oxygen into the system and negating the lethal cardiac rhythm.

Is V fib a form of pea?

Approximately 300,000 out-of-hospital cardiac arrests (OHCA) occur annually in the United States, with a survival of around 8%. The initial rhythm may be ventricular fibrillation (VF), pulseless ventricular tachycardia (VT), asystole, or pulseless electrical activity (PEA).

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Do you give epinephrine in pea?

Epinephrine should be administered in 1-mg doses intravenously/intraosseously (IV/IO) every 3-5 minutes during pulseless electrical activity (PEA) arrest. Higher doses of epinephrine have been studied and show no improvement in survival or neurologic outcomes in most patients.

Is ACLS open book?

It is 25 questions. You may use your book for reference, i.e. open book. Yes, there is a written test at the end of the ACLS class. It is 50 questions.

What if you fail ACLS test?

What happens if I fail the exam? You will receive three attempts for each course. After each attempt you will receive an exam scoring report showing any incorrect answers. If you fail three times you will need to retake the course.

How many ACLS algorithms are there?

Here’s What’s Inside the Course There are four primary ACLS algorithms in this ACLS training which include the Cardiac Arrest Algorithm, Bradycardia Algorithm, Tachycardia Algorithm, and the Post-Cardiac Arrest Algorithm.

What are shockable rhythms?

Shockable rhythms are rhythms that are caused by an aberration in the electrical conduction system of the heart.

What are the two shockable rhythms?

Shockable rhythms include pulseless ventricular tachycardia or ventricular fibrillation.

Why was hypoglycemia removed from ACLS?

Although no reason was given for the removal of hypoglycemia from the “H’s and T’s” in the American Heart Association ACLS algorithm, one possibility was that it could have encouraged clinicians to give dextrose in all patients with cardiac arrest.

Why is a defibrillator used?

AEDs are used to revive someone from sudden cardiac arrest. This usually occurs when a disruption in the heart’s electrical activity causes a dangerously fast heartbeat (ventricular tachycardia) or a fast and irregular heartbeat (ventricular fibrillation).

What does BLS stand for?

Basic Life Support, or BLS, generally refers to the type of care that first-responders, healthcare providers and public safety professionals provide to anyone who is experiencing cardiac arrest, respiratory distress or an obstructed airway.

Is defibrillation the same as cardioversion?

There is an important distinction between defibrillation and cardioversion: Defibrillation — Defibrillation is the asynchronous delivery of energy, such as the shock is delivered randomly during the cardiac cycle. Cardioversion — Cardioversion is the delivery of energy that is synchronized to the QRS complex.

Do you give epinephrine in asystole?

When treating asystole, epinephrine can be given as soon as possible but its administration should not delay initiation or continuation of CPR. After the initial dose, epinephrine is given every 3-5 minutes.

What is the difference between VFIB and Vtach?

Vfib is rapid totally incoordinate contraction of ventricular fibers; the EKG shows chaotic electrical activity and clinically the patient has no pulse. Vtach is defined by QRS greater than or equal to . 12 secs and a rate of greater than or equal to 100 beats per minute.

Is asystole a rhythm?

Survival rates in a cardiac arrest patient with asystole are much lower than a patient with a rhythm amenable to defibrillation; asystole is itself not a “shockable” rhythm.

Is Sinus a rhythm?

Sinus rhythm is the name given to the normal rhythm of the heart where electrical stimuli are initiated in the SA node, and are then conducted through the AV node and bundle of His, bundle branches and Purkinje fibres. Depolarisation and repolarisation of the atria and ventricles show up as 3 distinct waves on ECG.

Is Vtach shockable?

Ventricular tachycardia (v-tach) typically responds well to defibrillation. This rhythm usually appears on the monitor as a wide, regular, and very rapid rhythm. Ventricular tachycardia is a poorly perfusing rhythm; patients may present with or without a pulse.

When is amiodarone given?

For cardiac arrest, amiodarone is used after the third shock for ventricular fibrillation and ventricular tachycardia that is unresponsive to shock delivery, CPR, and vasopressors. For tachycardia with a pulse, amiodarone may be considered, and expert consultation should be obtained prior to its use.

How many times can you give amiodarone in a code?

Epinephrine1 mg q3-5 min. Drip: 0.1- 0.5 mcg/kg/minVasopressin40 units IV x 1Amiodarone300mg IV over 1-2 seconds May repeat 150 mg IV x 1.Lidocaine1 – 1.5 mg/kg over 2-3 min, then may repeat 0.5-0.75 mg/kg in 5-10 min. Max: 3 mg/kg.Calcium Chloride5-10 ml (0.5-1 gm) over 2-5min

How many questions are on the ACLS exam?

What to expect for the written test: The ProACLS written test has about 50 multiple-choice questions. The written test is also required and typically takes an hour of time to complete. The passing score for the written test is 85% or higher.

What is the PSA score for ACLS?

Welcome to the American Heart Association Student Website! ACLS and PALS also include a Precourse Self-Assessment that is required for entry into the course. A score of 70% or higher is necessary to pass and print your report.

What is the passing score for ACLS?

You must bring the AHA ACLS textbook to class with your completed test results. Passing Score = 70% (If a score of 70% is not achieved in each section, please review the text and retest the section).

Can someone fail ACLS?

STEP 3 – Take the Exam You need to achieve a passing score of 80% or better. If you don’t pass on your first attempt, don’t worry. We will let you know right away whether you pass or fail and you can retake the exam until you pass.