Cold‐induced cutaneous vasoconstriction in humans: Function, dysfunction and the distinctly counterproductive

Abstract

New Findings What is the topic of this review?This review presents an update and synthesis of normal mechanisms of human cutaneous vasoconstriction in response to cold stress. It then discusses conditions in which cutaneous vasoconstrictor responses are excessive or insufficient and cases in which cold‐induced vasoconstrictor responses become counter to maintaining thermal and haemodynamic homeostasis. What advances does it highlight?The review highlights our current understanding of the mechanisms that mediate alterations in cold‐induced cutaneous vasoconstriction in pathology and environmental extremes, which has important clinical implications for preventing cold‐ and cardiovascular‐related deaths. Abstract In humans, cold‐induced peripheral vasoconstriction is an essential element of body temperature regulation. Given that the thermoregulatory system responds rapidly to changes in skin temperature, sympathetically mediated cutaneous vasoconstriction represents a crucial ‘first line of defense’ against excessive reduction in body temperature. Sympathetic noradrenergic vasoconstrictor nerves cause a rapid decrease in skin blood flow, thus increasing the insulative capacity of the skin and decreasing heat loss from the body. Small changes in the activity of these nerves are also responsible for the subtle changes in skin blood flow that occur with normal daily activities or minor changes in environmental temperature. With ageing, hypertension and other conditions, the cutaneous reflex vasoconstrictor response can become excessive or insufficient. Healthy older adults have impaired reflex vasoconstriction, which may result in an impaired ability to defend body temperature in some circumstances. Hypertension is associated with augmented vasoconstriction, which could have pathological implications for left ventricular afterload in individuals already at risk for cardiovascular events. Finally, in some cases, the reflex vasoconstrictor response becomes distinctly counterproductive to its own goals of maintaining cardiovascular and thermoregulatory homeostasis. Examples include Raynaud's phenomenon, in which exaggerated vasoconstriction can produce ischaemia in the periphery, and the cutaneous vasoconstrictor response to therapeutic body cooling in severe hyperthermia, which can limit the heat exchange necessary to prevent serious heat illness.

Cognitive Processes Unfold in a Social Context: A Review and Extension of Social Baseline Theory

“…Cutaneous vasoconstriction and vasodilations are part of the homeostatic process of thermoregulation. Peripheral vasoconstriction reflexively serves as a defense mechanism to conserve internal body temperature, and vice versa for peripheral vasodilation (Alba et al, 2019). In social baseline theory, social inclusion indicates a positive social environment, and the presence of added positive social support would have pushed individuals above their baseline social expectations.…”

Seasonal variation in U.S. hospitalizations for chronic limb‐threatening ischemia

“…26,27 Accordingly, a potential explanation for the seasonal fluctuation in CLTI may be cold-induced peripheral vascular vasoconstriction in addition to other factors. 28 32,33 The results of this study may help to identify individuals at greatest risk for hospitalization and death through patient and provider education efforts. Patients with known PAD should be counseled about strategies to minimize cold exposure and employ good wound prevention in the winter, the time of greatest risk of CLTI onset.…”

Neonatal thermal response to childbirth: Vaginal delivery vs. caesarean section

“…Sympathetically mediated cutaneous vasoconstriction represents the "first line of defence" during exposure to cold environmental temperatures. Decreases in mean skin and/or internal temperatures cause reflex activation of sympathetic vasoconstrictor nerves, resulting in cutaneous vasoconstriction and decreases in skin blood flow [65][66][67].…”