(11) Hyperhidrosis (excessive perspiration) frequently occurs between the
second and the third week.
(12) The scab gradually separates, revealing intact skin which is thin, soft,
poorly keratinized, and easily injured.
NOTE:
Keratin is a protein found in the outermost layer of the skin. Keratin is
waterproof and resistant to friction and helps resist bacterial invasion.
c. Third Degree--Necrosis of Skin and Cutaneous Tissue. This injury
involves whole skin thickness and extends into subcutaneous tissue leading to
ulceration.
(1) Vesicles may be present but are more commonly bluish-purple in color
and hemorrhagic, smaller, and do not extend to the tip of the involved fingers or toes.
(2) Edema of the entire foot or hand is usually present and appears in an
average of six days.
(3) Most patients have burning, aching, throbbing, or shooting pains
beginning on the 5th to 17th day following an early period of anesthesia.
(4) The skin overlaying the area of third degree frostbite may form a black,
hard, dry scab.
(5) The scab finally separates, exposing underlying granulation tissue
(newly formed tissue produced in the healing of wounds).
(6)
Healing occurs in an average of 68 days.
(7) Hyperhidrosis (excessive perspiration) and cyanosis may appear
between the fourth to tenth week after the injury and persist for months. This results in a
prolonged, uncomfortable convalescence.
(8) Trauma and infection due to injury other than cold may complicate the
degree of injury and result in extensive tissue loss, systemic manifestations of infection,
and even wet gangrene requiring emergency amputation.
d. Fourth Degree-Complete Necrosis and Loss of Tissue. There is a
destruction of the entire thickness of the part including bone resulting in loss of the
injured part.
(1) Upon rewarming, the skin may turn deep red, purple, or appear mottled
and cyanotic.
MD0587
5-8