Thermographical investigation of decubitus ulcers.

1. Posterior body reference thermograms indicate that in general a similar thermal body pattern of humans does exist. 2. The buttocks, hips, and thighs of a nude subject are thermally cool regions, possibly indicating poor vascular circulation and/or large fat concentrations. 3. Thermograms of the same anatomical area on the same subject under controlled environmental conditions are thermally similar. 4. The scapular region is from 1 to 2 deg F hotter than the sacral region for subjects reclining on Mylar. 5. The 1 deg temperature differential thermograms and the reference thermogram while the subject is on Mylar, in many ways, denote the geometrical shape of the underlying bone structure, especially the bones of the scapulae and sacrum. 6. On the degree temperatue differential thermograms, the anatomical regions most accused of being decubitus ulcer prone are the regions of highest temperatures: the scapulae, sacrum, elbows, and calves. 7. During reactive hyperemia, the visible red flare over the sacrum and coccyx becomes very intense in the first few minutes and then gradually diminishes. The thermal flare persists longer than the visible flare. The extended duration of the thermal flare over the visible red flare is attributed to a continued local elevated metabolic tissue rate caused by the previous engorgement of blood. 8. The thermal mottling seen in the first minute after releasing the load is believed to have been caused by the rapid infusion of blood and the dilation of affected vessels responsible for making up the blood flow debt which occurred during the period of ischemia. 9. A posterior body heating effect noticed immediately after the subject left the Mylar film has been attributed to the insulative qualities of the film. The cooling effect is more difficult to explain, but it is thought that the higher than average room temperature caused an increased evaporative cooling rate response of the two subjects either before getting off the film or immediately after getting off and therefore reduced the temperature of the skin. 10. The maximum reactive hyperemic temperature difference, the difference between the initial standing reference thermogram and the maximum flare temperature observed during tissue hyperemia, may be as high as 12 deg F. 11. Males on the average have larger flare patterns than females, 5.7 in.2 and 4.7 in.2, respectively. The flare areas were computed from thermograms taken 2 to 3 minutes after off-loading of tissue. 12. With the average distance from the buttock's fold to the highest and lowest thermal flare indication being lower for females (3.2 and 5.9) than for males (3.8 and 6.4), a relationship between the site or decubitus ulcer formation and the pelvic bone structure of the sexes may well exist. 13. No two thermal flare patterns are similar either in size or in shape. Thermal flare patterns occur along the centerline of the body at the sacrum and coccyx level. 14...