Page 89 - PJ MED OPS Handbook 8th Ed

Altitude Illness

SPECIAL CONSIDERATIONS:
1. ACUTE MOUNTAIN SICKNESS (AMS)
2. Usually occurs at altitudes of 8,000ft and higher
3. Consider pretreatment when rapid ascent to altitudes above 8,000ft may occur:
a. Acetazolamide (Diamox) 125mg bid started 24 hours before ascent
b. Dexamethasone (Decadron) 4mg PO bid started 24 hours before ascent for
patients allergic to sulfa drugs, take with food
c. Ground test all meds before ops
4. Consider pretreatment if rapid ascent above 11,500ft occurs (as with airlifts):
a. Dexamethasone (Decadron) 4mg PO q6hr within 24 hours of ascent plus acetazol-
amide (Diamox) 125mg PO bid (if not allergic to sulfa)
5. Symptoms may occur as quickly as 3 hours after ascent
6. Can avoid onset by limiting initial ascent to no higher than 8,000ft then 1,000ft per day
thereafter. The key to prevention is slow, gradual ascent. Everyone acclimatizes differently.
7. HIGH ALTITUDE CEREBRAL EDEMA (HACE)
8. Rare below 11,500ft
9. Headache is common at altitude. Ataxia and altered mental status at altitude are HACE
until proven otherwise.
10. HIGH ALTITUDE PULMONARY EDEMA (HAPE)
11. Caused by the hypoxia of altitude, HAPE is the most common cause of death from alti-
tude illness.
12. Usually occurs above 8,000ft. Respiratory distress at high altitude is HAPE until proven
otherwise.
13. Nifedipine (Procardia) is recommended as prophylaxis in personnel who have a history
of previous HAPE and are required to operate at altitude. Acetazolamide (Diamox), silde-
nafil (Viagra), tadalafil (Cialis), dexamethasone (Decadron), salmeterol (Serevent), and
albuterol (Proventil) may be considered if nifedipine is not available.

WARNING HACE and HAPE may coexist in the same patient!

Signs and Symptoms:
1. AMS is generally benign and self-limiting, but symptoms may become debilitating. Worsening
condition should prompt consideration of a more life-threatening condition (HAPE or HACE)
a. AMS: Diagnosis is made in presence of headache AND one or more of the following: anorexia,
nausea, vomiting, insomnia, dizziness, lassitude, or fatigue
b. No correlation with fitness level (likely genetic predisposition)
2. HACE: Unsteady/wide based/unbalanced (ataxic) gait with altered mentation are hallmark signs
3. HAPE: Dyspnea at rest is the hallmark sign. Other symptoms may include cough, crackles upon
auscultation, pink frothy sputum, tachypnea, tachycardia, fever, central cyanosis, or low oxygen
saturation disproportionate to the elevation level.

Chapter 8. Tactical Medical Emergency Protocols (TMEPs) n 87