+Defining altitude High altitude Very high altitude Extreme altitude Physiological and symptomatic changes often vary according to the altitude involved. The Lake Louise Consensus Definition for<unk>  has set widely used criteria for defining<unk>  symptoms. In the presence of a recent gain in altitude, the presence of the following: Symptoms: at least two of: * Shortness of breath at rest * Cough * Weakness or decreased exercise performance * Chest tightness or congestion Signs: at least two of: * Crackles or wheezing (while breathing) in at least one lung field * Central blue skin color * Tachypnea (rapid breathing) * Tachycardia (rapid heart rate) Acute mountain sickness and high altitude cerebral<unk>  may also be present in conjunction with<unk> , however these symptoms may be subtle or not present at all. The most reliable sign of<unk>  is severe fatigue or exercise intolerance, especially in a climber that was previously not displaying this symptom.
High-altitude pulmonary edema
High-altitude cerebral edema
Decompression sickness
Chronic mountain sickness
Monofixation syndrome
Athletic heart syndrome
Pulmonary-renal syndrome
Cardiorenal syndrome