Responses of the hands and feet to cold exposure

Abstract

An initial response to whole-body or local exposure of the extremities to cold is a strong vasoconstriction, leading to a rapid decrease in hand and foot temperature. This impairs tactile sensitivity, manual dexterity, and muscle contractile characteristics while increasing pain and sympathetic drive, decreasing gross motor function, occupational performance, and survival. A paradoxical and cyclical vasodilatation often occurs in the fingers, toes, and face, and this has been termed the hunting response or cold-induced vasodilatation (CIVD). Despite being described almost a century ago, the mechanisms of CIVD are still disputed; research in this area has remained largely descriptive in nature. Recent research into CIVD has brought increased standardization of methodology along with new knowledge about the impact of mediating factors such as hypoxia and physical fitness. Increasing mechanistic analysis of CIVD has also emerged along with improved modeling and prediction of CIVD responses. The present review will survey work conducted during this century on CIVD, its potential mechanisms and modeling, and also the broader context of manual function in cold conditions.

Keywords: cold-induced vasodilatation; finger blood flow; manual function; sympathetic nervous system.

Figure 1.

General schematic of typical CIVD responses and measured variables in finger skin temperature during immersion in cold water. Reprinted from Cheung and Daanen, Microcirculation 2012; 19:65–77. Used with permission.

Figure 2.

Thermal sensation (top) and thermal discomfort (bottom) during whole-hand immersion into 5, 8, 10, and 15°C water. * Thermal discomfort was significantly higher during the entire 30 min of 5°C immersion for 5°C, with no differences among 8, 10, and 15°C. In contrast, all temperatures elicited the same thermal sensation. Adapted from Mekjavić et al., Appl Physiol Nutr Metab 2013; 38:14–20. Used with permission.

Figure 3.

Index finger temperature and thermal comfort after 30 min of cold-water immersion of the whole hand in 8°C water over 10 d of acclimation. Index finger temperature remained similar but thermal comfort steadily improved throughout acclimation. Adapted from Geurts et al., Appl Physiol Nutr Metab 2006; 31:110–7. Used with permission.

Figure 4.

Average temperature (T_avg) in the 5 toes of the detrained foot (top) and vascular countermeasure foot (bottom) during the 30-min cold-water immersion performed pre- (open bars) and post-35 d horizontal bed rest (dark bars). *Significant decrease in average and big toe temperatures after bed rest in the detrained foot, but no differences were seen in the foot with the sub-atmospheric vascular pressure countermeasure throughout bedrest. Adapted from Keramidas et al., Appl Physiol Nutr Metab 2014; 39:369–74. Used with permission.

Figure 5.

An example of evoked twitch force of the first dorsal interosseous muscle in one subject at 4 different stages during cold water immersion of the hand. (1) Initial [right index finger temperature (T_if) = 29.5°C, and skin temperature above the first dorsal interosseus (T_fdi) = 31.5°C], (2) nadir cold-induced vasodilatation (CIVD) (T_if = 9.5°C, T_fdi = 17.2°C), (3) apex CIVD (T_if = 13.3°C, T_fdi = 14.8°C), (4) final (T_if = 12.1°C, T_fdi = 14.1°C). Reprinted from Geurts et al., Eur J Appl Physiol; 2005; 93:524–9. Used with permission.

Figure 6.

Representative finger skin temperature responses and frequency of occurrence during cold water (8°C) immersion derived from 9 participants and 5 fingers over 13 immersions of the right hand. Reprinted from Mekjavić et al., Eur J Appl Physiol; 2008; 104:193–9. Used with permission.

Figure 7.

Observed (symbols) and predicted (lines) lower quartiles of the time for the fingertips to reach a contact temperature of 7°C for wood, nylon, steel, and aluminum. Adapted from Geng et al., Ann Occup Hyg; 2006; 50:851–62. Used with permission.