Peninsula Sleep Laboratory has returned from its international six weeks research expedition in the Himalaya. After a 10 day hike up to the EV-K2-CNR Italian Research Pyramid (http://www.evk2cnr.org) at 5050 meters in the Kumbu Valley. Several days to acclimatize were required before embarking on 18 nights in a row of sleep studies. Twenty three researchers conducted almost as many projects over the 21 days at the Pyramid to expand our understanding of how the human body works, particularly in a physiological sense, so that new treatments for sea level and high altitude diseases may be developed.
Professor Keith Burgess was the Principle investigator on two different sleep projects in conjunction with Professor Phil Ainslie (Canada), Dr Sam Lucas (New Zealand), Dr Jim Cotter (New Zealand), Dr David McLeod (USA) and Dr Aparna Basnet (Nepal). This research included a follow up study of sleep during alteration of cerebral blood flow which they first attempted in 2008 at the Pyramid. In addition to this a new study of central sleep apnea during different pH conditions was conducted.
High altitude induces central sleep apnea in most subjects which provides a stable model with which to work for these projects. The insights that we gain from this model may be able to be applied to sick patients at sea level who also have central sleep apnea. In addition it stresses the normal human physiology in ways that do not occur at sea level. Studying normal subjects at high altitude may provide new understandings of how the normal human body works.
A mobile sleep lab was setup with the help of Compumedics (www.compumedics.com) who provided blue tooth portable Polysomnography equipment for live acquisition. Four sleep studies per night were conducted in camp style beds with trans-cranial cerebral blood flow monitoring and arterial blood samples were taken during sleep. Ventilatory responses to hypoxia and hypercapnia were studied during the daytime with cardiac and vascular function analysis simultaneously.
Many months of analysis will now begin unraveling the data collected in order to gain a better understanding of mechanisms behind central sleep apnoea. Watch this space for more information.