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Asia, Nepal, Dhaulagiri Himal, Medical Research at High Altitude

Medical Research at High Altitude. The E-3 expedition (Dr. Kenneth Kamler, expedition physician, and Dr. Christian Macedonia, director of medical research) was in the field from April 21-May 30. There were 15 expedition members, including five medical doctors. We used the standard approach to the south (Nepal) side of Everest, flying from Kathmandu to Lukla and then trekking to the standard expedition Base Camp area on the Khumbu Glacier. We returned via the same route. We were a medical research expedition and did not attempt to climb any peak.

The 1999 E-3 project’s goals included high-altitude research, real-time biomonitoring, telemedicine and an education program involving “live transmission” from Mt. Everest to a number of schools. Research took place en route to, and at, Everest Base Camp (17,500'). Five members climbed through and above the Khumbu Icefall (19,000'+) in order to gather additional altitude data and to test the function of real-time biomonitoring equipment. We obtained permit space for Nuptse to do this, as the first two camps above Everest BC are the same as for Everest. The team treated numerous climbers and Sherpas at Everest Base Camp and also conducted free village medical clinics.

At various times en route, as well as during a climb through the Khumbu Icefall, team members wore compact, ca. four-pound biomonitoring devices. These instruments both recorded locally, and transmitted in real-time, vital signs including heart rate, core body temperature, skin temperature, activity level and GPS location. This data was displayed on computer screens showing the position of each climber “live” on a topographic map along with corresponding physiological information. Researchers at Base Camp and at Yale, 10,000 miles away, were able to monitor both the physical condition and precise location of the climbers. These devices functioned well and may serve as a useful adjunct to certain types of climbs in the future.

Newly available compact imaging duplex Doppler ultrasound equipment was used to gather data on how the blood flow rates in the carotid (neck) and brachial (arm) arteries change as a response to a hypoxic (low oxygen) environment. Comparing differences in circulatory flow rates, we were able to document significant change in blood flow patterns. The data appeared to show a significant shunting of the blood flow from one area of the body to another as an adaptation to a hypoxic environment. In some cases, the blood flow to the headmore than doubled, while the blood flow to the arms and legs dropped to 25 percent of typical flow rates. The pounding headaches, poor appetite, muscle cramps, etc., that climbers experience may be explained, at least in part, by the significant redistribution of blood away from less vital organs and areas, such as the stomach, to the brain in an attempt to survive a low-oxygen environment. The project collected a large data set of imaging duplex Doppler ultrasound of blood flow at high altitude.

Drs. Kamler and Macedonia suggest that climbers going to high altitude consider the pneumococcus vaccination called Pneumovax. It is a one-time vaccination that is considered safe and effective at preventing the major subtypes of pneumonia caused by pneumococcus bacterium. Pneumovax is usually only given to the elderly and people with impaired immune systems. High altitude appears to produce similar risks in impairment of healing and in damage to the system that removes contaminants from our airways. Pneumovax has minimal risks to high-altitude climbers with potential life-saving properties.

Scott Hamilton