Cold injuries to the lower
extremity
Matthew Spiva
Introduction
The purpose of this discussion is to review the signs,
symptoms, and treatment of cold injuries of the lower
extremity.
Assessing cold injuries
 Assess for systemic hypothermia
 Neurovascular assessment
 HPI: temperature + wind velocity = Wind chill, duration
of exposure, and time ellapsed since exposure.
 PMH: Tetanus status, antibiotic allergy, alcoholism, drug
use, mental status, PVD, smoker.
Discussion
 Hypothermia
 Raynauds
 Trenchfoot/Immersion foot
 Chilblains/Pernio
 Frost bite
Hypothermia

Hypothermia

- 98.6 F 37 C
Average body temperature

- 95 F
Patient unaware of 1/3 of the events around them

- 93.2 F 34 C
Extreme judgment errors, amnesia to current events

- 91.8 F 33.2 C
Frequent cardiac dysrhythmias (A-fib)

- 87.8 F 31 C
Loss of shivering

- 82.4 F 28 C
Pupils dilated

- 80.6 F 27 C
Flaccid body

- 78.8 F 26 C
Loss of consciousness

- 77.7 F 25-24 C
Loss of DTRs and vasoconstriction

- 68 F 20 C
Loss of pupil reflex to light

- 64.4 F 18 C
Flat EEG

- 51.9 F 10.5 C
Lowest cardiac activity

- 48.2 F 9 C
Lowest survival temperature recorded
35-35.5 C
Hypothermia
 A patient that presents with frostbite may also have
hypothermia and it must be considered prior to the
treatment of frostbite
 The patient with hypothermia may present with:
 Mild cases
 Shivering
 Slow mentation
 Poor coordination
 Moderate to severe
 Violent shivering
 Muscle rigidity
 Stupor
 Hypotension
 Lowered respiration
http://www.firstaidforeveryone.ie/wpcontent/uploads/2011/07/hypothermia-first-aid3.jpg
Hypothermia
 Treatment:
 Slow rewarming performed by colonic irrigation, warmed IV,
Dialysis, and inhalation re-warming
 Monitor vital signs and labs for worsening condition
Raynaud’s
http://www.northcoastfootcareblog.com/wp-
content/uploads/2008/01/raynauds-2.jpg
Raynaud’s phenomenon
 An exaggeration of vasomotor responses to cold or
emotional stress
 Hyperactivation of the sympathetic nervous system
causing extreme vasoconstriction of the peripheral blood
vessels, leading to tissue hypoxia
 Chronic, recurrent cases of Raynaud’s phenomenon can
result in atrophy of the skin, subcutaneous tissues, and
muscle. In rare cases it can cause ulceration and even
ischemic gangrene
 Smoking, hormonal influence, and caffeine all worsen
and increase the intensity of the attacks.
http://sammyantha.hubpages.com/hub/AromatherapyBlends-Raynauds-phenomenon#
Raynauds Treatment

Control cold exposure

Special heated gloves

Meds:
 Calcium channel blockers: relax and open up small peripheral blood
vessels
 nifedipine (Adalat CC, Afeditab CR, Procardia), amlodipine (Norvasc)
and felodipine (Plendil)
 Alpha blockers: counteract the actions of norepinephrine
 prazosin (Minipress) and doxazosin (Cardura)
 Vasoldilators:
 nitroglycerin cream
 losartan (Cozaar), the erectile dysfunction medication sildenafil
(Viagra, Revatio), fluoxetine (Prozac, Sarafem)

Avoid: Beta blockers, birth control pills, and vasoconstrictors such as
pseudoephedrine

Surgery/procedures:
 Sympathetic nerve resection/ablation
 Nerve blocks
 Amputation
Trench foot
http://www.tumblr.com/tagged/trench-foot
Trenchfoot: Cold + wet  prolonged vasoconstriction 
tissue necrosis
 Most commonly found in military personnel, hunters,
and fishermen. The foot has been exposed to wet and
cold conditions for an extended period of at least 10
hours. In some instances, the area may appear similar
to severe frostbite. The affected limb becomes
edematous and appears white, waxy, cyanotic, and
mottled
 Symptoms initially include numbness, tingling, and
hypereshtesia
 Blistering, swelling, erythema, ecchymosis, and
ulceration may occur
http://www.madisonpodiatrist.com/blog/post/war-horse-filmstar-got-trench-foot.html
http://trialx.com/g/Trench_Foot4.jpg
http://trialx.com/g/Trench_
Foot-3.jpeg
http://www.accessmedicine.ca/search/searchAM
ResultImg.aspx?rootterm=trench+foot&rootID=
35918&searchType=1
http://homeinthehills.co.nz/health
.html
Trenchfoot
 Prevention:
 Wear dry mixed fiber socks
 Treat hyperhidrosis
 Keep feet dry
 Treatment:
 Elevate the extremity and gently rewarm the limb resulting
in hyperemia followed by erythema, intense burning and
tingling
 A post hypothermic phase occurs at 2-6 weeks resulting
in cyanosis of the limb
 Permanent cold sensitivity can be a sequela of trench
foot
Chilblains/Pernio
http://healthndine.com/wp-content/uploads/chilblains.jpg
Chilblains/Pernio
 Chilblains are the mildest form of cold injury. Usually,
they are found in female patients on the dorsum of the
hands and feet and on the face where the skin has been
exposed to cold, wet, and windy conditions.
 Pruritus and erythematous, dry, rough, and swollen skin
are evident. Papules that may later ulcerate may also be
present.
 Chilblains usually will last the duration of cold weather,
with symptoms ceasing on the return of warm weather.
Patients have to be reminded to protect any exposed
areas and to apply lotion to eliminate the pruritus and
rough skin.
Chilblains/Pernio
 May be secondary to underlying medical condtions:

-CML

-Anorexia nervosa

-Dysproteinemias
 -Macroglobulinemia

-Cryoglobulinemia, cryofibringonemia, cold agglutinins

-Anitphospholipid Ab syndrome
 - Raynauds
 - SLE
http://www.funscrape.com/Image/31
833/Chilblains.html
http://www.funscrape.com/Ima
ge/31838/Chilblains.html
http://www.funscrape.com/Image/31
834/Chilblains.html
Chilblains/Pernio
 Treatment:
 Warming
 Exercise (promotes blood flow)
 Nifedipine
 Ca+ channel blocker
 Relaxes smooth muscle and creates vasodilation
 10 to 20 mg PO tid
 Wound care if necessary
 Avoid nicotine, cold, EtOH
Frostbite
http://carlosdaman.wordpress.com/2009/03/15/pictures-pictures-morepictures/frostbite-72542211/
Frostbite

Water conducts heat 25 times faster than air, thus a person who has cold
and wet feet is more susceptible to frostbite.

Predisposing factors are the African-American population, poor
nutritional status, the amount of tissue exposed, tight shoe gear or
clothing restricting blood flow, lack of activity, concurrent injury, previous
cold injury

Underlying diseases such as diabetes, peripheral vascular disease, and
renal failure also predispose one to frostbite.

The pathophysiology of frostbite is thought to occur in the following
ways:
 1. Slow freezing leads to ice crystal formation in the extra-cellular
fluid. (Most cases)
 2. Rapid freezing causes ice crystal formation intra-cellularly.
Touching the skin to freezing metal can result in this type of
freezing.
 3. Vasomotor responses to freezing yield vasoconstriction and stasis
resulting in increased blood viscosity and coagulation. Perfusion is
inadequate.
 This + slow freezing = frostbitten tissue
More on Frostbite
 Frostbite is a disease of morbidity not mortality
 Affects mostly mountaineers, cold weather enthusiasts,
soldiers, those who work in the cold, the homeless, and
individuals stranded in the cold
 Frostnip no permenant tissue damage
 Frostbite is 2/2 both immediate cold induced cell death and
a more gradual inflammatory process and tissue ischemia.
 Fluid and electrolyte fluxes cause lysis of the cell
membranes and cell death resulting in inflammation with
the release of thromboxane A2, PG F2-alpha, bradykinins,
and histamine the end result of which is ischemia and
necrosis.
 This process is made worse with thawing and
refreezing
Frostbite
 Symptoms:
 Firm/hard and cool to the touch
 Affected area appears waxy, white, or blotchy blue-gray
 Pain, burning, pruritis, but may not be apparent until the
body part is warmed
 Clumsiness due to joint and muscle stiffness
 Profound edema, hemorrhagic and/or serous blisters,
necrosis and gangrene may occur
Frostbite Classifications

Like bums, frostbite is classified according to the depth of destruction.
Currently, two classifications exist. The first depicts the extent of
injury by degrees:
 First degree:
 Hyperemia and edema are evident. Hard white plaques form after
rewarming. The patient experiences pruritus or burning.
 This stage is characterized by the absence of blister formation.
 Second degree:
 Hyperemia with vesicle formation occurs. The skin is red and feels hot and
dry after treatment. Swelling occurs, along with desquamation of the blebs
after re-warming.
 Third degree:
 Necrosis of the skin and underlying tissue occurs. Blebs are hemorrhagic.
Rewarming leads to severe edema at the 6-day mark.
 Anesthesia ensues, followed by aching and throbbing. The necrotic tissue
forms an eschar that forms an ulcer after undergoing desquamation.
 Fourth degree:
 Complete necrosis and loss of tissue occur. Bone can be destroyed.
Rewarming causes a mottled or deep red appearance. No edema occurs in
the injured area. Gangrene and mummification are evident quickly.
Demarcation may take up to 90 days.
Frostbite Classifications

The second classification system, which appears to be gaining
widespread support, is described as follows:
 Superficial frostbite: This affects the epidermis and dermis. The
area is white, but the tissues are resilient when palpated.
 Deep frostbite: Not only are the epidermis and dermis affected, but
extension to tendons and bone occurs. When the tissue is palpated,
there is a lack of resilience. The frostbitten area is stiff. Often, it
resembles a piece of frozen meat .
http://comingbackalive.com/winterfrostbite.html
http://www.greatnorthernprepper.com/wpcontent/uploads/2012/10/frostbite-feet.jpg
http://www.project-himalaya.com/gallery-everest-frostbite.html
http://doctorrennie.files.wordpress.com/2012/05/frostbite-feetmay-19.jpg
Frostbite Treatment
 Usually requires analgesics during thawing
 Superficial frostbite (frostnip) can be rewarmed by
applying constant warmth with gentle pressure
from a warm hand (w/o rubbing) or by placing the
affected body part against another part of the body
that is warm
Frostbite treatment

Full thickness frostbite is usually treated best by rapid thawing at
temperatures slightly above body temperature
 Immerse body part in warm water 40-42 C (104 – 107.6 F) until it
has returned to normal temperature (approx.. 30 minutes) (i.e.
whirlpool)
 Keep affected area elevated at room temperature uncovered or with
a loose sterile dressing
 When one is in the field and a part becomes frostbitten, there
should be no rewarming if a chance of refreezing exists. It is
better to arrive at a hospital in a frozen state than to refreeze
and increase tissue destruction and hypoxia.
Frostbite

Deep frost-bite, which is analogous to a deep burn, may require
surgery after 2 or 3 weeks.

Radiographs are obtained to rule out the presence of gas. Technetium
bone scans can depict cold spots in the deep frostbitten part that
correlate with a poor prognosis for healing.

One should remember this important admonition when treating frostbite:
January's frostbite is July's amputation

Amputation or debridement should not be performed until a line of
demarcation between viable and dead tissue is established at
approximately 3-5 weeks
 Blisters and blebs are left intact if they are hemorrhagic.
 Clear blisters are débrided and are covered with a non-adherent
sterile dressing.
 Débridement of necrotic tissue is not performed acutely.
 Cloudy blisters are degloved and are treated with local wound care.
 Eschars can form, and they may be incised, especially in areas of
movement
Medications/Interventions:
 Due to vascular thrombosis in addition to regular treatment
one may administer heparin and/or tPA as this has been
shown to increase favorable outcomes
 U of U conducted a study from 2001-2006 using tPA and
conventional treatment and compared them to patients who
just received conventional therapy. The result was those who
received tPA had only a 10% amputation rate compared to 41%
in the conventional only group.
 Tetanus prohylaxis
 NSAIDs good for preventing inflammation
 Opiods are necessary for pain control
 Hyperbarics were thought not to work previously but recent
studies show that there has been some benefit
 Pentoxifylline has shown good outcomes when used in
animals with frostbite. (Often used in claudication)
Summary of key points
 Assess for hypothermia and treat accordingly
 Raynaud’s – avoid cold climates, keep hands and feet warm,
avoid nicotine, EtOH, caffeine, beta blockers, birth control
pills, and any vasoconstrictors
 Treat with warming affected area, heated gloves, Calcium
channel blockers (nifedipine), Alpha blockers (Prazosin),
Vasodilators (Nitro cream), nerve blocks, nerve ablation,
amputation.
 Trenchfoot – Avoid prolonged LE exposure to wet/cold,
change socks, treat hyperhydrosis (botox?), elevate and
gently rewarm, and wound care as necessary.
 Pernio – live somewhere warm, keep exposed areas
covered, warm the injured tissue, nifedipine, local wound
care if necessary.
 Frostbite – Do not thaw if refreezing may occur, requires
analgesics while thawing, superficial - apply heat, full
thickness - immerse in whirlpool, leave bloody bullae alone,
drain clear bullae, deroof cloudy bullae, local wound care,
obtain x-rays, heparin, tPA, NSAIDs, opiates, tetanus,
hyperbarics, Pentoxifylline.
 January’s frostbite is July’s amputation
References

Küpper T, Steffgen J, Jansing P. Cold exposure during helicopter rescue operations in the Western Alps. Ann

Occup Hyg 2003; 47:7.

http://healthcare.utah.edu/publicaffairs/publications/HSR/PDF/Fall_07/Clinical%20Firsts.pdf

Eric stamps lecture on cold injuries (SMU)

Crawford MC, frostbite, eMedicine, July 18th 2007

Up to date subject search keywords “Cold injuries”

Kroeger K, Janssen S, Niebel W. Frostbite in a mountaineer. Vasa 2004; 33:173.

Atenstaedt RL. Trench foot: the medical response in the first World War 1914-18. Wilderness Environ Med
2006; 17:282.

Twomey JA, Peltier GL, Zera RT. An open-label study to evaluate the safety and efficacy of tissue plasminogen
activator in treatment of severe frostbite. J Trauma 2005; 59:1350.

Bruen KJ, Ballard JR, Morris SE, et al. Reduction of the incidence of amputation in frostbite injury with
thrombolytic therapy. Arch Surg 2007; 142:546.

Hayes DW Jr, Mandracchia VJ, Considine C, Webb GE. Pentoxifylline. Adjunctive therapy in the treatment of
pedal frostbite. Clin Podiatr Med Surg 2000; 17:715.

http://www.mayoclinic.com/health/raynauds-disease/DS00433/DSECTION=treatments-and-drugs

Pocket Podiatrics by Leon Watkins, DPM

http://www.epodiatry.com/chilblains.htm

Reamy BV. Frostbite: review and current concepts. J Am Board Fam Pract 1998; 11:34.

Cauchy E, Marsigny B, Allamel G, et al. The value of technetium 99 scintigraphy in the prognosis of amputation
in severe frostbite injuries of the extremities: A retrospective study of 92 severe frostbite injuries. J Hand Surg
Am 2000; 25:969.

Twomey JA, Peltier GL, Zera RT. An open-label study to evaluate the safety and efficacy of tissue plasminogen
activator in treatment of severe frostbite. J Trauma 2005; 59:1350.

Bruen KJ, Ballard JR, Morris SE, et al. Reduction of the incidence of amputation in frostbite injury with
thrombolytic therapy. Arch Surg 2007; 142:546.

Finderle Z, Cankar K. Delayed treatment of frostbite injury with hyperbaric oxygen therapy: a case report. Aviat
Space Environ Med 2002; 73:392.

Hayes DW Jr, Mandracchia VJ, Considine C, Webb GE. Pentoxifylline. Adjunctive therapy in the treatment of
Thank You