Acetazolamide is the standard carbonic anhydrase (CA) inhibitor used for acute mountain sickness (AMS), however some of its undesirable effects are related to intracellular penetrance into many tissues, including across the blood-brain barrier. Benzolamide is a much more hydrophilic inhibitor, which nonetheless retains a strong renal action to engender a metabolic acidosis and ventilatory stimulus that improves oxygenation at high altitude and reduces AMS. We tested the effectiveness of benzolamide versus placebo in a first field study of the drug as prophylaxis for AMS during an ascent to the Everest Base Camp (5340 m).
View Article and Find Full Text PDFHigh Alt Med Biol
December 2015
In 1853, Stanhope Templeman Speer published a two-part paper in The Association Medical Journal on Mountain Sickness. Speer was a physician who had worked at the Brompton Hospital for Chest Diseases in London and had been Professor of Medicine in Dublin. He was also an Alpine climber and had made the first ascent of one of the Wetterhorn peaks.
View Article and Find Full Text PDFAnecdotal evidence surrounding Tibetans' and Sherpas' exceptional tolerance to hypobaric hypoxia has been recorded since the beginning of high-altitude exploration. These populations have successfully lived and reproduced at high altitude for hundreds of generations with hypoxia as a constant evolutionary pressure. Consequently, they are likely to have undergone natural selection toward a genotype (and phenotype) tending to offer beneficial adaptation to sustained hypoxia.
View Article and Find Full Text PDFThis paper is an overview of my career as a hospital physician with special interest in respiratory diseases. Alongside this career, I have been fortunate to be able to pursue my professional hobby of high altitude medicine and physiology, partly in the laboratory but mainly in the field in the great ranges of the world.
View Article and Find Full Text PDFThe 1960-1961 Himalayan Scientific and Mountaineering Expedition, commonly known as the Silver Hut Expedition, was a unique project to study the physiology of acclimatization in human lowlander subjects at extreme altitude over a prolonged period and also to make an attempt on Makalu, an 8470-m peak. The leader was Sir Edmund Hillary, and Dr. Griffith Pugh was the scientific leader.
View Article and Find Full Text PDFObjective: To demonstrate that the Snow Snorkel can be used safely by healthy volunteers buried in snow for up to 1 hour.
Methods: Nine healthy male volunteers were placed in a shoulder-width trench and buried with snow to a depth of 30 to 40 cm. The study was divided into 2 stages.
Oxygen delivery (DO2) calculated from cardiac output, haematocrit (Hct) and arterial oxygen saturation (SaO2), has been obtained on six subjects at sea level (London) and after slow ascent to 5000 meters (Chamlang base camp) at rest and during mild exercise (25 watts and 50 watts). Haematocrit was increased in all six subjects at 5000 m and expressed as haemoglobin (Hb) rose from a mean (+/- standard error; SEM) of 13.8 +/- 0.
View Article and Find Full Text PDFJohn West is well known to the "Hypoxia" community for his many contributions to the physiology and Pathophysiology of high altitude and for his leadership of the 1981 American Medical Research Expedition to Everest. He is known to the wider medical world for his researches into respiratory physiology especially gas exchange in the lung and perhaps even more for his numerous books on these topics. His publication list numbers over 400 original papers.
View Article and Find Full Text PDFTravel Med Infect Dis
October 2006
With increasing numbers of people travelling to high altitude destinations for recreation or work, there is a need for practitioners of Travel Medicine to be familiar with altitude illnesses and the physiology of altitude. In mountainous areas travellers may also be exposed to problems of heat and cold. This article reviews these topics and gives practical advice on the management of the clinical problems involved, together with a discussion of underlying mechanisms, as far as they are understood at present.
View Article and Find Full Text PDFInfections and acute mountain sickness (AMS) are common at high altitude, yet their precise etiologies remain elusive and the potential for differential diagnosis is considerable. The present study was therefore designed to compare clinical nonspecific symptoms associated with these pathologies and basic changes in free radical and amino-acid metabolism. Nineteen males were examined at rest and after maximal exercise at sea level before (SL(1)/SL(2)) and following a 20 +/- 5 day ascent to Kanchenjunga base camp located at 5100 m (HA).
View Article and Find Full Text PDFLewis Griffith Cresswell Evans Pugh (1909-1994), best known as the physiologist on the successful 1953 British Everest Expedition, inspired a generation of scientists in the field of altitude medicine and physiology in the decades after World War II. This paper details his early life, his introduction to exercise physiology during the war, and his crucially important work in preparation for the Everest expedition on Cho Oyu in 1952. Pugh's other great contribution to altitude physiology was as scientific leader of the 1960-1961 Himalayan Scientific and Mountaineering Expedition (the Silver Hut), and the origins and results of this important expedition are discussed.
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