Do over 200 million healthy altitude residents really suffer from chronic Acid-base disorders?

As the oxygen tension of inspired air falls with increasing altitude in normal subjects, hyperventilation ensues. This acute respiratory alkalosis, induces increased renal excretion of bicarbonate, returning the pH back to normal, giving rise to compensated respiratory alkalosis or chronic hypocapnia. It seems a contradiction that so many normal people at high altitude should permanently live as chronic acid-base patients.

Altitude adaptation through hematocrit changes.

Adaptation takes place not only when going to high altitude, as generally accepted, but also when going down to sea level. Immediately upon ascent to high altitude, the carotid body senses the lowering of the arterial oxygen partial pressure due to a diminished barometric pressure. High altitude adaptation is defined as having three stages: 1) acute, first 72 hours, where acute mountain sickness (CMS or polyerythrocythemia) can occur; 2) subacute, from 72 hours until the slope of the hematocrit increase with time is zero; here high altitude subacute heart disease can occur; and 3) chronic, where the hematocrit level is constant and the healthy high altitude residents achieve their optimal hematocrit.

Decompression sickness following seawater hunting using underwater scooters.

Since the 1960s there have been several reports of divers suffering from decompression sickness (DCS) after repetitive breath-hold (BH) diving. In the period from 1995 to 2000 John Batle observed apparent DCS in 30 free divers competing with underwater scooters in the sea around Mallorca. The cases were treated successfully with recompression therapy.

High altitude diving depths.

In order to make any sea level dive table usable during high altitude diving, a new conversion factor is created. We introduce the standardized equivalent sea depth (SESD), which allows conversion of the actual lake diving depth (ALDD) to an equivalent sea dive depth. SESD is defined as the sea depth in meters or feet for a standardized sea dive, equivalent to a mountain lake dive at any altitude, such that [image omitted] [image omitted] [image omitted] Mountain lakes contain fresh water with a relative density that can be standardized to 1,000 kg m(-3), and sea water can likewise be standardized to a relative density of 1,033 kg m(-3), at the general gravity of 9.