THE EFFECT OF BODY HEATING AND COOLING ON THE ANKLE AND TOE SYSTOLIC PRESSURES IN ARTERIAL-DISEASE

Although changes in body temperature alter limb blood flow, little information exists on the effect of body heating and cooling on systolic pressures in limbs with arterial disease. Ten patients with stable claudication were studied. Mean ankle systolic pressure index during body cooling (0.79 +/- 0.04) exceeded (p < 0.01) both the value during routine test (0.69 +/- 0.03) and during heating (0.65 +/- 0.04). The individual, paired difference in ankle systolic pressure index between cooling and heating exceeded 0.15 in seven limbs and between cooling and routine test in five. Mean toe systolic pressure index during heating, but not during cooling, was lower than during routine test (p < 0.01). There was no significant difference in the mean toe systolic pressure index between heating and cooling. However, compared with heating, toe systolic pressure index increased with cooling in 12 limbs and decreased in eight, including three with loss of measurable pressure. The paired difference in toe systolic pressure index between cooling and heating exceeded 0.15 in 10 limbs and between cooling and routine test in eight; whereas between heating and routine test the paired difference was within 0.15 in all but three limbs. The results indicate that changes in body temperature have significant effects on distal pressures in arterial disease. Preliminary warming in routine tests should improve reproducibility.