Table 4. The four clinical phases that characterize the course of non-freezing cold injury^*.

Phase	Clinical signs
Prehyperemic phase	Pale, white skin, disturbances of sensation, loss of deep sensation, occasionally blisters
Cyanotic phase	Early phase of rewarming with appearance of pain
Hyperemic phase	In the hours after rewarming: pain, swelling, reddening, capillary supply still impaired, petechiae
Posthyperemic phase	A phase lasting weeks or months featuring cold sensitivity, pain, hyperhidrosis, and reduced sensation

^* Modified from (2)