Healthcare providers at every level need assistance to perform more effective CPR, and ZOLL Medical Corporation is committed to providing technology that can help them do that.


The latest guidelines from the American Heart Association (AHA) and the European Resuscitation Council stress how crucial CPR quality is to patient survival. The recently published 2013 AHA consensus statement on CPR quality reinforces this message, focusing on the critical parameters of CPR that can be enhanced to help providers optimise their performance.

‘High quality’ is defined as providing compressions:

  • at proper rate
  • at proper depth
  • with correct release,
  • with limited interruptions.

Achieving these four parameters is undeniably difficult, and studies show that rescuers are often unable to deliver high-quality CPR. Until recently, technology to help healthcare professionals administer CPR was virtually non-existent; they were on their own when performing this critical skill under highly stressful circumstances.

According to the new AHA consensus statement, "monitoring of CPR quality is arguably one of the most significant advances in resuscitation practice in the past 20 years, and one that should be incorporated into every resuscitation and every professional rescuer programme". Where systems have integrated new technology and focused on improving their CPR quality, in and out of hospital, survival rates from sudden cardiac arrest have doubled – or even tripled.

Optimisation of ‘good CPR’ metrics

The target rate is between 100 and 120 compressions a minute. If the rate is too slow, the heart will fill with blood, but won’t be able to move it on to maintain effective circulation to the brain and other organs; too fast and the heart will not fill sufficiently. Similarly, if compressions are too shallow – less than 5cm (2in) – it won’t be possible to generate the critical blood flow needed to deliver oxygenated blood to the heart and brain.

Another key component is full chest recoil. During CPR, the rescuer needs to ‘come off’ the chest so that the heart can refill with venous blood before the next compression. This maximises output with each compression. Studies show, however, that rescuers frequently lean on the patient’s chest, impeding full recoil.

Finally, the chest compression fraction (CCF) quantifies the percentage of time that chest compressions are actually being delivered during resuscitation. The recommended CCF is >80%. Minimising factors that interrupt compressions helps to significantly improve this number.

Realising better outcomes

Data from electronics manufacturing services providers in Arizona and a university-based medical centre in California prove that high-quality CPR saves lives.

In the pre-hospital setting, specialised training and ZOLL technology combined to more than double survival to discharge. These results were documented in a paper published in the Annals of Emergency Medicine in 2013. Also, at the University of California, San Diego, survival from in-hospital cardiac arrest doubled, from 21 to 42%, on the wards; in the intensive care unit, survival to discharge increased from 23 to 32%.

Tools that improve CPR performance

Equipped with the unique CPR Dashboard, featuring Real CPR Help, ZOLL defibrillators are designed to support healthcare providers throughout an entire cardiac event. All of the information needed to perform high-quality CPR is clearly displayed on the defibrillator screen. Real-time displays of CPR depth and rate, as well as a compression release indicator, are easily seen. And thanks to the CPR idle timer, rescuers know exactly how long the patient has been without compressions.

In addition, See-Thru CPR technology filters out compression artefacts so that the patient’s underlying heart rhythm can be displayed during CPR. In this way, See-Thru CPR minimises the duration of pauses between compressions.

Delivering high-quality CPR is difficult. But it’s easy to see that, when it comes to helping healthcare providers implement the best possible CPR, no one offers as much support as ZOLL.