Defibrillation is the process of delivering a controlled electrical current through the heart during cardiac arrest to terminate an abnormal electrical rhythm.
Types of devices:
- Automated External defibrillator (AED).
- Internal defibrillator.
- Manual defibrillator.
- Semi-automated defibrillator.
- Implantable cardioverter-defibrillator (ICD).
- Wearable Defibrillators.
In this article we will cover the manual defibrillator.
What is used to conduct the electrical current from the device to the patient.
- Hand-held paddle.
- Self-adhesive pads.
Conventional positions (anterolateral)
- One paddle is placed on the left fourth or fifth intercostal space on the midaxillary line.
- The second paddle is placed just to the right of the sternal edge on the second or third intercostal space.
Type of waveforms:
(depend on the device)
Factors that affect success rate:
- Early defibrillation.
- Energy selected.
- Electrode size.
- Paddle–skin coupling material.
- Number and time interval of previous shocks.
- Phase of ventilation.
- Distance between electrodes (size of the chest).
- Ventricular fibrillation (VF).
- Pulseless Ventricular Tachycardia (pVT).
- Non shockable rhythms include:
- Pulseless electrical activity.
- Patient presenting with signs of life.
- Directly injuring myocardial cells.
- Inducing post-shock dysfunction.
- Skin burns.
- Transmitted shock to the operator.
- 200 J for monophasic.
- 360 J for Biphasic.
Procedure (The ARC Guidelines 2016):
Required a very good communication and a trained team
C: Compressions Continue
O: Oxygen away (if free flowing BVM)
A: All others clear
C: Charging defibrillator
H: Hands off (compressor should say I’m safe)
E: Evaluating rhythm
D: Defibrillate or Disarm