Blood volume and haemoglobin concentration at altitudes above 18,000 ft. (5500 m)

A micro-haematocrit for determining the packed cell volume and haemoglobin concentration on capillary blood.

Gruneberg, 1942; Meyerstein, 1942; Smith, 1944; Harris, Gilding, and Smart, 1951 ; Sabine and Nickolai, 1952) and those open at both ends (Gram and Norgaard, 1923; Van Allen, 1925a and b; Guest, 1938 ; Kato, 1938 and 1940; Miller, 1939 Hamre, 1940; Benditt, Straube, and Humphreys, 1946; Shils, Sass, and Goldwater, 1952). All these tubes suffer from drawbacks either in design or method of use. A...

Relationship between haemoglobin concentration and packed cell volume in cattle blood samples.

A convention that has been adopted in medicine is to estimate haemoglobin (HB) concentration as a third of packed cell volume (PCV) or vice versa. The present research set out to determine whether a proportional relationship exists between PCV and Hb concentration in cattle blood samples, and to assess the validity of the convention of estimating Hb concentration as a third of PCV. A total of 4...

Effects of two years' intermittent stay at high altitudes on the pulmonary blood volume in man.

Outbreak of Wilderness/Backcountry/Travelers’ Diarrhea at a Himalayan Base Camp at 4000 m/13,125 ft

Introduction: Wilderness or backcountry diarrhea is a type of travelers’ diarrhea commonly caused by Cryptosporidium and Giardia, which can survive freezing temperatures. Campsites pose additional risks worldwide, irrespective of developing or developed regions, due to inadequate hygiene. Methods: In a first of its kind, an outbreak of wilderness diarrhea...

New insights into ocular blood flow at very high altitudes.

Little is known about the ocular and cerebral blood flow during exposure to increasingly hypoxic conditions at high altitudes. There is evidence that an increase in cerebral blood flow resulting from altered autoregulation constitutes a risk factor for acute mountain sickness (AMS) and high-altitude cerebral edema (HACE) by leading to capillary overperfusion and vasogenic cerebral edema. The re...