Site-specific Study on Warming Using Disposable Warmer “Kairo” in Healthy Subjects / 日本温泉気候物理医学会雑誌

ABSTRACT

  [Purpose] Acral coldness is a condition in which the fingers and/or toes are cold despite normal central body temperature. Regardless of the presence or absence of disease, many people suffer from acral coldness, especially elderly people. One method of relieving acral coldness is to heat the hands with a disposable warmer called “Kairo,” but this method interferes with daily work. We investigated whether or not heating other upper-limb parts with a pair of warmers can relieve acral coldness.   [Methods] After obtaining informed consent, 30 people who usually had acral coldness without other diseases received the Kairo holders for their necks, elbows, and wrists. Eighteen participants used a pair of Kairo warmers for each area for one week, respectively. The remaining participants wore only the holder to know the heat retention effect of the holders. All participants separately evaluated their acral coldness of the upper limbs and the cumbersomeness of holders and/or Kairo by using a 10cm visual analog scale (VAS). To measure the therapeutic effect of the Kairo, the temperature and blood flow of the surface of both hands were examined by thermography and laser speckle contrast analysis (LASCA) at the day after finishing each warming period. These evaluations were conducted after a 20-minute adaptation at 24°C.  [Result] The VAS of acral coldness of upper limbs decreased during the periods of warming on the neck and elbows with Kairo compared to the period without Kairo. There was no difference in the VAS value of the cumbersomeness among the neck, elbows, and wrists areas. The hand temperature on the day after the end of warming decreased slightly after elbow warming.  [Conclusion] We found that the coldness of the hand was improved by warming other parts, even if the hand was not warmed, but the effect varied depending on the warming area. No therapeutic effect was detected, but this was considered to be a problem in setting the measurement conditions. We believe these results will lead to new ways to improve acral coldness.