This point can be stressed to travelers as the key point in preventing severe altitude illness. Evaluating the patient that has already descended from altitude with altitude illness is a slightly different process. One can assume that the descent has definitively treated the altitude problem, so one should now be alert for either complications of altitude illness, or the possibility of a different diagnosis. Persistent neurologic symptoms that don t show rapid signs of improvement at low altitude should be investigated with a brain scan. In severely comatose patients, the coma can rarely persist for several days, but usually patients regain consciousness fairly rapidly.
Altered sensorium clears up first, along with the headache.
The gait ataxia can persist for 24-48 hours post descent, and is usually the last symptom to clear up. HAPE is a high risk for a subsequent pulmonary infection, and a low threshold should be used to prescribe appropriate antibiotics if persistent productive cough, or fever, persist. Chest x-ray in HAPE usually shows fluffy infiltrates that are often more prominent on the right side than the left. A dense consolidation should raise the question of pneumonia or pulmonary infarct.