Wilderness and Rescue Medicine 7th Edition Jeffrey Isaac, PA-C and David E. Johnson, MD

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Section III: Critical System Problems and Treatment

to therapy. These do not act fast enough to help in an acute attack. Encourage the patient to inhale as deeply as possible while the inhaler is discharged into the mouth. The efficiency of the inhaler can be improved using a spacer to contain the vapors while the patient inhales. This is simply a plastic tube with the inhaler on one end and the patient on the other. You can improvise a spacer by using a plastic water bottle with the end cut off. It is safe to make several attempts to abort the asthma attack with an inhaler. However, do not delay moving to the next step if it is apparent that the patient cannot effectively inhale the medica- tion. If use of the inhaler fails to reduce symptoms within a few minutes, the patient will need an injection of epinephrine.

three times over the next hour. Each 6 to 10 puff dose is roughly equivalent to a nebulizer treat- ment in a clinic or hospital. If evacuation is likely to take more than 3 hours, add a dose of prednisone at 1 mg/kg given by mouth (40–60 mg for an adult, 20 mg for a child). As with anaphylaxis, this will reduce lower airway inflammation and the chance of another attack. Risk Versus Benefit This protocol is for use in severe respiratory dis- tress leading to respiratory failure caused by lower airway constriction in a known asthmatic. It is safe, effective, and carries little risk compared to the problems associated with inadequate oxygen- ation. It is an important life-saving skill for both basic and advanced practitioners operating in remote areas.

General Principles

Asthma Treatment WILDERNESS PROTOCOL Respiratory distress not responding to the inhaler: • PROP • Epinephrine 0.3 mg IM. • β-agonist rescue inhaler (6 -10 puffs up to 3x over the next hour), then as prescribed. • Prednisone 1 - 2 mg/kg up to 60 mg PO. • Evacuation

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General Principles

Severe Asthma Wilderness Perspective

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High-Risk Problem: • Persistent abnormal mental status. • Incomplete response to treatment. • HFA/MDI continues to be ineffective. • The patient is getting worse.

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Field treatment

Low Risk High Risk

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Before medications like albuterol became avail- able, epinephrine was a first-line treatment for an asthma attack. It is the same medication used for the emergency treatment of anaphylaxis. It is given in the same concentration and dose by intramuscular injection (see the allergy and ana- phylaxis chapter). The Wilderness Protocol for severe asthma calls for 0.3–0.5 mg injected into the lateral aspect of the thigh. For children, the dose is 0.01 mg per kilogram up to 0.3 mg. The patient will usually feel better within a few minutes. One dose of epinephrine may completely abort the asthma attack, but a second dose may be given within as little as 5 minutes if needed. Once symptoms improve, the patient should self-administer his or her own inhaler at a dose of 6 to 10 puffs up to

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The disease itself can become a significant prob- lemwhen the triggers cannot be avoided. Asthma can also generate significant lower airway inflam- mation and continued wheezing with exacerba- tions that may continue for several hours or days. Even if the initial attack is completely aborted, the risk of further exacerbations may warrant evacu- ation from the field. Ideally, anyone whose life you have just saved with epinephrine should receive early follow-up medical care. If the symptoms are under control, the evacuation need not be an emergency one. In settings where evacuation is unreasonably danger- ous or impractical, prednisone can be continued daily for up to 5 days. The patient should continue to use his or her albuterol inhaler as needed.