What is a shockable and non shockable rhythm?
The cardiac arrest treatment algorithm divides cardiopulmonary resuscitation into the treatment of shockable rhythms - ventricular fibrillation (VF) and pulseless ventricular tachycardia (VT) (Figure 1); and the treatment of non-shockable rhythms - asystole and pulseless electrical activity (PEA) (Figure 2).
This refers to whether a particular class of cardiac dysrhythmia is treatable using defibrillation. The two "shockable" rhythms are ventricular fibrillation and pulseless ventricular tachycardia while the two "non–shockable" rhythms are asystole and pulseless electrical activity.
- Treatment. PEA is treated much like asystole. It is not a shockable rhythm because the electrical system in the heart is actually working properly. Shocking the patient is done to 'reset' the heart's rhythm, but the problem in PEA isn't in the conduction of electrical stimuli in the heart.
- The most common irregular heart rhythms that require cardioversion include atrial fibrillation and atrial flutter. Life-saving cardioversion may be used to treat ventricular tachycardia (a rapid, life-threatening rhythm originating from the lower chambers of the heart).
- A: When there is not an AED available the 2 rescuers should switch places every 5 cycles of CPR ( 1 cycle is 30 compressions followed by 2 ventilations ) or every 2 minutes.
Description. Defibrillation - is the treatment for immediately life-threatening arrhythmias with which the patient does not have a pulse, ie ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT). Cardioversion - is any process that aims to convert an arrhythmia back to sinus rhythm.
- Synchronized electrical cardioversion is used to treat hemodynamically unstable supraventricular (or narrow complex) tachycardias, including atrial fibrillation and atrial flutter. It is also used in the emergent treatment of wide complex tachycardias, including ventricular tachycardia, when a pulse is present.
- Sinus tachycardia (often referred to as sinus tach) is a rhythm which is formed by the electrical impulse originating in the SA node in the normal manner. However, the rate is faster than normal. The normal heart rate range is 50-100 beats per minute in adults.
- Ventricular tachycardia is a very fast heart rhythm that begins in the ventricles. They fill with blood from the atria, or top chambers of the heart, and send it to the rest of the body. Ventricular tachycardia is a pulse of more than 100 beats per minute with at least three irregular heartbeats in a row.
Asystole may be treated with 1 mg epinephrine by IV every 3–5 minutes as needed. 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.
- For this, a general rule of thumb is that brain cells begin to die after approximately 4-6 minutes of no blood-flow. After around 10 minutes, those cells will cease functioning, and be effectively dead. That said, there are some exceptions to that rule.
- Medically, a “flat-line” is known as asystole, meaning no (heart) contraction. It might seem common sense that if there is no contraction you might want to contract it with a shock. The truth about why this will never “restart” the heart lies in how the heart creates its life giving beat.
- The advanced cardiac life support (ACLS) 2010 guidelines allow vasopressin 40 IU IV as a 1-time dose treatment option in VF and asystole. This treatment can be given either before epinephrine or after the first dose of epinephrine.
Updated: 2nd October 2019