Wilderness and Rescue Medicine 8th Edition

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Section III: Critical System Problems and Treatment

more than 30 minutes of CPR. Regardless of the cause of cardiac arrest, the minimal chance of a successful resuscitation does not justify any sig- nificant level of risk to survivors or rescuers.

General Principles

Cardiac Arrest WILDERNESS PROTOCOL

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Do Not BEGIN CPR: • Obviously dead from lethal injury • Submerged under H 2 0 greater than 1 hour

General Principles

Cardiac Arrest WILDERNESS PROTOCOL

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Start CPR and ALS otherwise*

STOP CPR : • Spontaneous pulse resumes • Authorized medical professional pronounces the patient dead • Rescuers are exhausted or at risk • Fatal injuries are discovered • After 30 minutes of sustained cardiac arrest* * See Thermoregulation for recommendations specific to severe hypothermia.

* See Thermoregulation for recommendations specific to severe hypothermia.

© 2018 WMA

some oxygenation and perfusion of the brain and vital organs. For CPR to be effective, the patient’s critical systems must still be intact. CPR will not save or restore life in cases where the cardiac arrest was caused by massive trauma or shock. The survivors of cardiac arrest are typically patients who have experienced ventricular fibrillation or other cardiac arrhythmia due to a heart attack. The lungs and brain are still intact and capable of resuming function if perfusion is restored. The application of electrical defibrilla- tion within a few minutes of the arrest may be successful in reestablishing functional cardiac rhythm, at least temporarily. Unfortunately, CPR and defibrillation are not very useful unless there is rapid access to hospital care. CPR by itself is unlikely to restore normal cardiac rhythm and defibrillation will not fix the cause of the cardiac arrest. The chance of a suc- cessful resuscitation without definitive medical care is extremely low. If your backcountry safety budget is limited in money, space, or weight, a defibrillator is not the best way to spend it. The Wilderness Protocol for cardiac arrest reflects our current level of experience and under- standing. We hold out some hope for cardiac arrest caused by respiratory failure due to events like drowning or lightning strike that could be reversed by prompt oxygenation of the lungs and chest compressions to boost perfusion. How often this might occur is left to speculation since there are simply not enough monitored cases to know. Except under extraordinary circumstances not reproducible in the backcountry or offshore set- ting, normothermic patients do not recover after

*

© 2018 WMA

Severe Bleeding and Shock Controlling blood loss is the other essential ele- ment of circulatory support in the BLS process. Bleeding from an artery is the most immediately life threatening and can usually be controlled by wound packing and well-aimed direct pres- sure. The site must be exposed, and the bleeding source identified. Packing and direct pressure will be effective most of the time if applied firmly enough, in the right place, and long enough for the blood to clot. A tourniquet may be used on an extremity to control severe bleeding temporarily while you deal with other critical system problems. It can also be used to stop bleeding long enough for you to expose and identify the source to better aim your direct pressure. Conversion to a pressure dressing should be accomplished as soon as practical as an alternative to control bleeding. With unmanage- able bleeding, however, there may be no choice but to leave a tourniquet in place. After 6 hours of continuous application, a tourniquet should be left in place until definitive care is reached. This prolonged tourniquet use will generally result in ischemic and infarcted tissue and compartment syndrome. In an effort to save the limb, we recom- mend getting a patient to definitive care as soon as possible.