No association between hand and foot temperature responses during local cold stress and rewarming

Abstract

Purpose: The purpose was to examine whether associations exist between temperature responses in the fingers vs. toes and hand vs. foot during local cold-water immersion and rewarming phases.

Methods: Seventy healthy subjects (58 males, 12 females) immersed their right hand or right foot, respectively, in 8 °C water for 30 min (CWI phase), followed by a 15-min spontaneous rewarming (RW) in 25 °C air temperature.

Results: Temperature was lower in the toes than the fingers during the baseline phase (27.8 ± 3.0 vs. 33.9 ± 2.5 °C, p < 0.001), parts of the CWI phase (min 20-30: 8.8 ± 0.7 vs. 9.7 ± 1.4 °C, p < 0.001), and during the RW phase (peak temperature: 22.5 ± 5.1 vs. 32.7 ± 3.6 °C, p < 0.001). Cold-induced vasodilatation (CIVD) was more common in the fingers than in the toes (p < 0.001). Within the first 10 min of CWI, 61% of the subjects exhibited a CIVD response in the fingers, while only 6% of the subjects had a CIVD response in the toes. There was a large variability of temperature responses both within and between extremities, and there was a weak correlation between finger- and toe temperature both during the CWI (r = 0.21, p = 0.08) and the RW phases (r = 0.26, p = 0.03).

Conclusions: Results suggest that there is generally a lower temperature in the toes than the fingers after a short time of local cold exposure and that the thermal responses of the fingers/hands are not readily transferable to the toes/foot.

Keywords: CIVD; Cold tolerance; Finger; Local cold injury; Rewarming; Toe; Water immersion.

Fig. 1

Average temperature (Tavg) of (a) the distal phalanx of the volar side of all fingers and toes and (b) the dorsal metacarpal and metatarsal region of the right hand and foot, respectively, obtained during the cold-water immersion test. Values are mean ± SD. Data are averaged every 30 s

Fig. 2

Thermography results showing average temperature (T _avg) of (a) the volar and (b) the dorsal side of the distal phalanx of the fingers and toes, (c) the total area of palm and sole, and (d) the total dorsal metacarpal/metatarsal area of the right hand and foot during the spontaneous rewarming phase. Values are mean ± SD. n = 69. *Significant difference between hand and foot (p < 0.001). B: a 5-min baseline phase, WWI: a 5-min warm-water immersion phase, RW: a 15-min rewarming phase

Fig. 3

Representative infrared-thermal images from a single subject during the baseline and the 15-min rewarming response of (a) the hand and (b) the foot. Color coding of temperatures are indicated on the right-hand side; the brighter colors represent a warmer limb (yellow), and the darker colors represent a colder limb (dark purple). Note (1) the rate of rewarming in the hand vs. the foot and (2) the distal to proximal rewarming pattern for the fingers

Fig. 4

Pearson’s product-moment correlation between the average temperature (T _avg) during the 5-min baseline and the 30-min cold-water immersion phase (upper graphs), and the 5-min baseline and the 15-min spontaneous rewarming phase (middle graphs), and the 30-min cold-water immersion phase and the 15-min spontaneous rewarming phase (lower graphs) in (a) all fingers of the right hand and (b) all toes of the right foot

Fig. 5

Pearson’s product-moment correlation between the average temperature (T _avg) of all fingers of the right hand and all toes of the right foot during (a) the 30-min cold-water immersion phase and (b) the 15-min spontaneous rewarming phase

Fig. 6

Changes from the warm-water immersion (WWI) phase in the average temperature (T _avg) of the non-immersed finger II and toe II during the hand and foot cold-water immersion test, respectively. Values are mean ± SD. # Significant difference from the previous timepoint (p ≤ 0.05)

Fig. 7

Changes from the warm-water immersion (WWI) phase in systolic (SAP) and diastolic (DAP) arterial pressure, and heart rate (HR) during the hand and foot cold-water immersion test, respectively. Values are mean ± SD. *Significant difference between hand and foot test (p < 0.05) ^#Significant difference in arterial pressure from the previous phase (p < 0.05)