The physiology of<unk>  centres around the alveolar gas equation; the atmospheric pressure is low, but there is still 20.9% oxygen. Water vapour still occupies the same pressure too—this means that there is less oxygen pressure available in the lungs and blood. Compare these two equations comparing the amount of oxygen in blood at<unk> : At Sea Level At 8400 m (The Balcony of Everest) Formula Pressure of oxygen in the alveolus Oxygen Carriage in the blood The hypoxia leads to an increase in minute ventilation (hence both low CO2, and subsequently bicarbonate), Hb increases through haemoconcentration and erythrogenesis. Alkalosis shifts the haemoglobin dissociation constant to the left, 2,3-BPG increases to counter this. Cardiac output increases through an increase in heart rate. The body's response to high<unk>  includes the following: * ↑ Erythropoietin → ↑ hematocrit and haemoglobin * ↑ 2,3-BPG (allows ↑ release of O2 and a right shift on the Hb-O2 disassociation curve) * ↑ kidney excretion of bicarbonate (use of acetazolamide can augment for treatment) * Chronic hypoxic pulmonary vasoconstriction (can cause right ventricular hypertrophy) People with high-altitude<unk>  generally have reduced hyperventilator response, impaired gas exchange, fluid retention or increased sympathetic drive. There is thought to be an increase in cerebral venous volume because of an increase in cerebral blood flow and hypocapnic cerebral vasoconstriction causing oedema.
Altitude sickness
Hangover
Sweating sickness
Dehydration
Motion sickness
Fatigue
Chronic mountain sickness
Carbon monoxide poisoning