2007, Piran, Slovenia

TRAINABILITY OF COLD INDUCED VASODILATION
Hein Daanen, Roy Raymann and Mark Stoop
TNO Defence, Security and Safety, Soesterberg, The Netherlands
Contact person: hein.daanen@tno.nl
Cold physiology
INTRODUCTION
Peripheral cold injuries are often reported in mountaineers. Not only low ambient
temperatures, but also the hypobaric circumstances are known to be major environmental risk
factors (Daanen and Van Ruiten, 2000). When the fingers are exposed to extreme cold for
several minutes, cold induced vasodilation (CIVD) occurs, that is reported to have protective
properties for cold injuries (Daanen and Van der Struijs, 2005). Repeated immersion in cold
water may lead to improved finger blood flow (Adams and Smith, 1962). In the latter study,
the subjects immersed their phalanxes in ice water four times daily for one month.
In this study we investigated if two weeks of repeated immersions of the hand in cold water
prior to a mountain expedition to the Ama Dablam in Nepal enhanced finger blood flow
response to cold.
METHODS
Eight subjects (6M, 2F, mean age 34 years) participated in the study. In July 2006 all subjects
immersed the middle finger of both hands in ice water and the CIVD reaction was determined
(pre-test). Fingertip temperature was measured using a small thermocouple at the volar side of
the middle finger.
Starting September 8, the subjects immersed one hand every day for 15 minutes in ice water
for 14 consecutive days. Four subjects trained the left hand, and four subjects trained the right
hand. During this training period, the pain score was measured using a 10cm visual analogue
scale.
Just prior to the flight to Nepal, September 22 at Schiphol airport, the same protocol as the
pre-test was followed to determine the changes in peripheral blood flow and pain score of the
trained and untrained hand (post-test).
In the base-camp Namche Bazar at 3340 m, again the middle fingers of both hands were
immersed in ice water (altitude-test).
The CIVD response was quantified using the onset time, minimum (Tmin) and mean finger
skin temperature (Tmean).
RESULTS
There was no difference in onset time, minimum and mean finger skin temperature between
the trained and untrained hands for the pre-test, post-test and altitude test (Table 1). Tmean
was higher in the pre-test than in the post-test and altitude test (P