Hypoxia is the state of insufficient oxygen delivery to the body’s tissues, whether from thin mountain air, smoke, foul cave gases, or diseases like emphysema or asthma. Because the brain is the most oxygen-hungry organ, hypoxia announces itself through impaired judgment long before more dramatic physical signs appear — which is what makes it dangerous.
Symptoms
Shortness of breath, coughing, rapid pulse, headache, dizziness, and a creeping euphoria or irritability. Fingernails and lips take on a bluish tinge. Coordination fails subtly: handwriting deteriorates, balance falters, simple counting becomes difficult.
Progression
Severe hypoxia produces tunnel vision, confusion, and loss of consciousness within minutes. Tissues begin to die after a few minutes more, with the brain leading the way. Survivors of prolonged hypoxia may carry permanent cognitive impairment.
Treatment
- Move to open, breathable air at once — descend if at altitude
- Loosen anything constricting the chest and throat
- Encourage slow, deep, regular breathing rather than panicked gasping
- Rest until lips and nailbeds regain color
- Certain imbibed or inhaled stimulants may open constricted air pathways