Altitude mountain sickness among tourist populations: a review and pathophysiology supporting management with hyperbaric oxygen

Abstract

In the mountain climbing community, conventional prevention of altitude mountain sickness (AMS) relies primarily on a formal acclimatization period. AMS symptoms during mountaineering climbs are managed with medication, oxygen and minor recompression (1524-2438 m altitude) using a portable chamber, such as the Gamow Bag. This is not always an acceptable therapy alternative in a predominantly elderly tourist population. The primary problem with reduced pressure at high altitude is hypoxaemia, which causes increased sympathetic activity, induces pulmonary venous constriction, while increasing pulmonary blood flow and regional perfusion. Rapid assents to altitude contribute to an increased incidence of decompression sickness (DCS). The treatment of choice for DCS is hyperbaric oxygenation, thus, treatment of high-altitude induced hypoxaemia using hyperbaric oxygenation (HBO(2)) is logical. Life Support Technologies group and the Center for Investigation of Altitude Medicine (CIMA, in Cusco, Peru) propose a comprehensive and multidisciplinary approach to AMS management. This approach encompasses traditional and advanced medical interventions including the use of a clinical HBO(2) chamber capable of recompression to three times greater than sea level pressure (3 atmosphere absolute (ATA)). The system uses a series of AMS hyperbaric treatment profiles that LST has previously developed to the US military and NASA, and that take greater advantage of vasoconstrictive effects of oxygen under true hyperbaric conditions of 1.25 ATA. These profiles virtually eliminate AMS rebound after the initial treatment often seen in conventional AMS treatment, where the patient is either treated at altitude, or does not recompress back to sea level or greater pressure (1.25 ATA), but returns directly to the same altitude where AMS symptoms first manifested.

Oxygen Concentration-Dependent Oxidative Stress Levels in Rats

“…When pilots of unpressurized aircrafts fly to areas at high altitudes, when climbers ascend high-altitude peaks and outpace their ability to acclimatize, or when divers inhaling compressed air return to the surface, the external pressure on the body decreases and the dissolved inert gases come out of solution in the form of bubbles in the body on depressurization [1, 2]. The resulting decompression sicknesses and air embolisms are initially treated by inhalation of oxygen-enriched air or exposure to mild hyperbaric oxygen at 1.25 atmospheres absolute (ATA) until hyperbaric oxygen therapy (100% oxygen delivered at 2-3 ATA) is administered [3–6]. Hypoxic or breathless patients with chronically obstructive pulmonary disease (COPD), who have low levels of oxygen in their blood, require oxygen at concentrations greater than that in room air to achieve arterial oxygen saturations between 88% and 92% [7].…”

Hyperbaric oxygen preconditioning for prevention of acute high-altitude diseases: Fact or fiction?

“…The monoplace chamber can only accommodate one person, and the multiplace chamber allows for the treatment of several patients at the same time ( Lind, 2015 ). There are also portable chambers ( Butler et al, 2011 ). Those portable chambers are for single use and can fit into a backpack when deflated, which are carried on most high-altitude expeditions.…”

“…The monoplace chamber can only accommodate one person, and the multiplace chamber allows for the treatment of several patients at the same time (Lind, 2015). There are also portable chambers (Butler et al, 2011). Those portable…”

Study on the Optimization and Oxygen-Enrichment Effect of Ventilation Scheme in a Blind Heading of Plateau Mine

“…At present, the most common factors for solving the problem of hypoxia in plateau areas are pressurized ventilation and oxygen supply. The equipment required for pressurization technology is very complicated, such as hyperbaric oxygen chambers [ 5 ], which are difficult to popularize; their scope and application population are very limited, which makes them more difficult to use in a plateau mine’s complicated operating environment. However, there are abundant basic theories in research about oxygen supply standards [ 6 , 7 ].…”