System performs flawlessly on battery power during training climb at 21,000 feet and sub-freezing temperatures - Research on oxygen deprivation aimed at improving treatment for critically ill patients
Bothell, WA and London, England, November 28, 2006- Sonosite, Inc. (Nasdaq: SONO), the world leader in hand-carried ultrasound, today announced that Xtreme Everest 2007 (http://www.xtreme-everest.co.uk) has selected the MicroMaxx hand-carried ultrasound system to perform cerebral perfusion studies for its research on human performance at extreme altitudes. The goal of the project is to place a medical and scientific team on the summit of Mount Everest in the spring of 2007 to study the effects of oxygen deprivation on the human body. Coordinated by the Centre for Aviation, Space and Extreme (CASE) Environment Medicine in London, the Everest ascent is the centrepiece of an extensive research program studying human performance at extreme altitude aimed at improving the care of the critically ill. The study -- the largest human biology study ever performed at high altitude -- will consist of examining more than 200 volunteers as they climb progressively higher into the thin atmosphere. More detailed research will be performed on a group of scientists planning to climb to the summit of Everest.

Dr. Chris Imray, a member of the Xtreme Everest 2007 training expedition on Cho Oyu scans a mountaineer with the Sonosite MicroMaxx system and P-17 probe. The aim of the training expedition was to test the medical equipment in a combined cold and altitude environment in the Himalaya similar to what will be encountered in the main Everest expedition in Spring 2007


"One of the major areas of interest is cerebral perfusion, the supply of blood to the brain, since we know that this can be seriously affected at high altitude," said Dr. Chris Imray, Consultant Vascular Surgeon and Hon Reader in Surgery Warwick Medical School and member of the training team. "We were looking for a robust, portable transcranial Doppler system that would be simple to use and reliable in an extreme environment. I used the MicroMaxx on the rehearsal climb to the summit of Cho Oyu in Tibet this autumn and it performed beautifully. We performed scans up to 6,400 metres (21,000 ft.) on battery power and in temperatures as low as -20 C; the system was operable within seconds of booting up and the images produced were very high quality," he said. The expedition team, all of whom work in anaesthesia, intensive care, vascular surgery or remote medicine, hope to show parallels between the human body pushed to its limits during critical illness and changes that occur in extreme environments.

The low oxygen levels in the blood of high altitude climbers is similar to those in critically ill patients on breathing machines with severe heart and lung conditions, "blue babies" and cystic fibrosis sufferers. The expedition team believes that by examining the volunteers and scientists as they push themselves to the limit of human performance that they will better understand what is happening to patients fighting for their lives in the intensive care unit. "Low oxygen levels (hypoxia) in the blood and cells are a critical factor in Intensive Care patients and the summit of Everest is by extraordinary coincidence exactly at the limit of human tolerance for hypoxia," said Dr. Mike Grocott, Director and Expedition leader and Consultant in Intensive Care.

"For many years, doctors and scientists believed that it would be impossible to climb Everest without supplementary oxygen. This all changed in 1978 when Reinhold Messner proved them wrong by reaching the summit without supplemental oxygen. Since then more than 100 individuals have accomplished the same feat. It is clear that were the mountain even a few meters higher this would be impossible. The summit of Everest is a wonderful natural laboratory for the study of the effects of critical hypoxia in humans."

MicroMaxx System Helps to Save a Climber's Life
On the 26th of August the Xtreme Everest embarked on a rehearsal expedition to Cho Oyu, which, at 8,201 metres (26,000 ft.), is the sixth highest mountain in the world. A short distance to the west of Mt Everest, it straddles the border between Tibet and Nepal. The aim of the training expedition was to test all the medical equipment in a combined cold and altitude environment similar to what will be encountered in the main expedition in Spring 2007. At one stage of the expedition the MicroMaxx system was unexpectedly used to examine an emergency casualty, when a North American mountaineer from another climbing party was suspected of having a stroke.

The Xtreme Everest team rapidly converted their DRASH (Deployable Rapid Assembly Shelter) laboratory into a high dependency unit, allowing Dr. Imray to examine the climber using the MicroMaxx system with the P-17 probe. Dr. Imray explains, "We used the Sonosite equipment to transmit sound waves through the thin part of his skull and look for blood flow to the brain. We were able to image his brain and see that on one side blood flow was absolutely normal and on the other side there was virtually no flow at all." Having confirmed that the mountaineer had indeed suffered a stroke, the team stabilized his condition and made immediate arrangements to evacuate the casualty, who was rapidly transported to a more comprehensive medical facility in Kathmandu. The patient has since returned to North America and is progressing well in a rehabilitation unit.

The MicroMaxx System
The laptop-sized, durable MicroMaxx system represents the technology crossover point between hand-carried ultrasound and larger, high-performance, cart-based systems. Sonosite products and technology deliver proven reliability and durability in conventional medical settings as well as some far more challenging environments, such as supporting rescue operations following natural disasters. Extensive quality controls such as "drop testing" ensure that Sonosite products continue to set the industry standard for both reliability and durability. The MicroMaxx system is backed by a five-year warranty, an industry first, far exceeding warranties available on competing products. The technology also allows for the system to go from "off" to scanning within seconds. This is vitally important in many medical situations where seconds really do count - whether getting crucial diagnostic information in an emergency or making the best use of time in a hectic daily schedule.

About CASE
CASE (www.ucl.ac.uk/case) has offices and human performance laboratories located within the Institute for Human Health Performance at the University College London archway campus, in the UK. The group conducts research, teaches courses and offers advice in the areas of space, aviation, high altitude, remote, dive and hyperbaric medicine and is comprised of a group of clinicians and scientists with specialist interests and training in the medicine and physiology of extreme environments. Central to its work is the concept that the study of human systems stretched to breaking point in extreme environments can increase the understanding of critically ill patients.

About Sonosite
Sonosite, Inc. (www.sonosite.com), the innovator and world leader in hand-carried ultrasound, is headquartered near Seattle and is represented by eight subsidiaries and a global distribution network in over 75 countries. Sonosite's small, lightweight systems are expanding the use of ultrasound across the clinical spectrum by cost-effectively bringing high performance ultrasound to the point of patient care. The company employs over 500 people worldwide.