Defibrillators in Remote Environments
One of the most common questions we receive from corporate clients after training is "Should I have a Defibrillator at our premises?"
Timely defibrillation is the single most important factor in terms of a successful resuscitation and the positioning of AEDs in public areas for use by lay people, with or without formal training, is of clear benefit to the casualty in a pre-hospital environment so should we advocate the use of AEDs in remote environments when we are far from help?
Most data that exists on the use of Defibrillators in a pre-hospital setting is taken from urban studies where transport to definitive care is relatively fast. Even though AEDs have increased survival from Cardiac Arrest to nearly 74%, survival to hospital discharge of those casualties who have been resuscitated ‘in the street’ is as low as 13% in the same study.(1)
Two important factors to consider are:
- Defibrillation is simply one link of the chain: Even if the casualty is successfully resuscitated by the lay rescuer, they will still require pre-hospital Advanced Care as well as transport to definitive care in hospital which cannot be guaranteed in a remote environment.
The heart may remain in Ventricular Fibrillation for 10-12 minutes from collapse (a few minutes more if preceded by effective CPR).(2, 3) With an AED close to hand we may be able to defibrillate well within this timeframe, however, successful recovery is still dependant on Advanced Life Support within 30 minutes and transfer to definitive care within 90 minutes.(4)
If the casualty is able to be defibrillated quickly but the remaining care is delayed is there any point in defibrillating or is this merely delaying the inevitable?
- While timely defibrillation can increase the chance of survival for some casualties, a defibrillator cannot not a guarantee successful resuscitation– a defibrillator cannot shock all heart rhythms and not all causes of Cardiac Arrest can be resolved by defibrillation.
Should you carry a Defibrillator in a Remote Environment?
As with any First Aid Needs Assessment, whether a Defibrillator should be provided, in any environment, will depend on several factors including, but not limited to:
- Proximity to definitive care
If you are unable to access Advanced Care within 30 minutes and Definitive Care within 90 minutes it is likely that if the casualty is resuscitated, the casualty is likely to arrest again.
- Client Group
Older casualties, in poor health with pre-existing medical conditions are more likely to experience Cardiac Arrest than young, fit, athletic people in good health.
Strenuous activities, stressful working environments and challenging climates are all factors which will increase the likelihood of Cardiac Arrest in come casualties.
The decision to provide a defibrillator is simply one decision to make following you Risk Assessment and Needs Analysis. If your risk assessment indicates that the probability of having to resuscitate a casualty is realistic, other elements of your Emergency Plan must also be adjusted including:
- Level of medical care immediately available
- The standard of medical equipment immediately available
- Evacuation and medical repatriation
If the Emergency Plan cannot cater for this risk, the risk must be brought down to a level which can be catered for. This can be achieved by reconsidering the venue choice, client group and health screening and the type of activity or environment.
If you are considering whether you need a defibrillator, you probably shouldn't be planning that activity, with those people, in that location and environment.
If you are to provide a defibrillator, also provide the means for the casualty to receive the remaining links in the chain in good time.
- Waalewijn RA, de Vos R, Tijssen JG, Koster RW. (2001) “Survival models for out-of-hospital cardiopulmonary resuscitation from the perspectives of the bystander, the first responder and, the paramedic”. Resuscitation. Nov;51(2):113-22.
- International Liaison Committee on Resuscitation (ILCOR). (2000) Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Part 4: Automated External Defibrillator: Key link in the chain of survival. Circulation 2000;108(Suppl 2):I60-I76.
- Cummins RO, Ornato JP, Thies WH, Pepe PE. (1991) Improving survival from sudden cardiac arrest: the “chain of survival” concept: as statement for health professionals from the Advanced Cardiac Life Support Subcommittee and the Emergency Cardiac Care Committee of the American Heart Association. Circulation 83:1832-47.
- Vukmir R. (2006) “Survival from prehospital cardiac arrest is critically dependent upon response time.” Resuscitation. 69:229-234.