Defibrillation Pads and Paddles


  • Defibrillation pads are used to facilitate cardioversion and defibrillation
  • some allow ECG monitoring and external pacing
  • paddles are becoming obsolete


Gel pads

  • used to reduce transthoracic impedance when paddles are applied directly to the chest wall to deliver a shock.
  • The packet containing the gel pads must not have been opened otherwise  the pads may have dried out.
  • The pads are for single patient use but can be used for multiple shocks during the same resuscitation attempt (? maximum number)
  • The pads not only limit transthoracic impedance but also protect the skin from being burnt.

Multi-function electrode (MFE) pads or self-adhesive defibrillator pads/electrodes

  • more commonly used
  • allow monitoring, defibrillation and pacing without additional monitoring electrodes or the operator needing to come into direct contact with the patient
  • The MFE pads provide a greater surface area for energy delivery, deliver more reliable charge, reduce the skin complications from current delivery and are safer for staff
  • Transthoracic impedance seems to be similar whether gel pads or MFE pads are used

Paddle/ pad size

  • larger size associated with higher success rates and less myocardial damage
  • Paddles/pads of 10–13 cm optimally reduce transthoracic impedance


There are two accepted positions to optimize current delivery to the heart:

  • (1) Anteroapical – one pad/paddle is placed to the right of the sternum just below the clavicle, and the other is centred lateral to the normal cardiac apex in the anterior or midaxillary line (V5–6)
  • (2) Anteroposterior – the anterior pad/paddle is placed over the praecordium or apex, and the posterior pad/paddle is placed on the back in the left or right infrascapular region.

In applying either gel pads or MFE pads there must be good contact between the pad and the skin (needs to be dry and clean) to enhance adherence and decrease the chance of arching/burns

  • The skin should be shaved if needed
  •  The pad should not be in contact with any other equipment including ECG dots, GTN pads, lines and cables

When paddles are used the pressure exerted needs to be at least 50 Newtons


  • Arcing (electricity travels through the air directly between electrodes and can result in explosive noises, burns and impaired delivery of current)
  • Electrical injury to bystanders
  • Risk of explosion if oxygen flow continues during shock delivery
  • Skin burns from repeated shocks
  • Myocardial injury and post defibrillation dysrhythmias and ‘stunning’
  • Skeletal muscle injury
  • Thoracic vertebral fractures


  • Some defibrillators allow transcutaneous pacing using self-adhesive defibrillator pads

CCC 700 6

Critical Care


Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of three amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC


  1. Anyone know if it’s problematic when defib pads are put on backwards, as in, posterior on front, anterior pad on back?

    • Back-to-front pads will work just fine for defibrillation but not for pacing. So if your patient is in VF, don’t bother removing the pads, just hit the button. On the other hand, if you are about to cardiovert a stable patient, and there is a possibility you might need to pace them immediately afterwards (say if they went into a profound heart block) first take a few seconds to peel the pads off and replace them the right way round.

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