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 Bleeding control is an essential part of Basic Life Support. A major artery that is severed or torn can cause shock and death within minutes. Because even profuse bleeding can be hidden by bulky or waterproof clothing, a thorough explora tion with a gloved hand is a mandatory in trauma assessment. In the ideal response, the bleeding site is quickly exposed, identified, and controlled with well-aimed direct pressure, packing as needed, and a pressure dressing. Reality is likely to be less elegant. There may be multiple injuries, blood everywhere, other critical system problems, or the need to move quickly away from a dangerous place. In these cases, a tourniquet can be applied to a bloody extremity temporarily while you deal with everything else. You can come back to examine the limb when you have time. In short term use, a tourniquet is a low-risk treatment for a high-risk problem. For a tourniquet to be effective it must be tight enough to completely block arterial blood flow to the extremity. This will be impossible to accom plish without the mechanical advantage provided by a windlass mechanism or multi-part buckle. The best devices currently in production use a windlass. Stretchy material is usually ineffective and improvised tourniquets are challenging to apply and maintain.