Browse categories and answer follow-up questions to refine your symptom profile.
History
HPI
Frostbite focused history
OPQRST
Onset
First noted numbness or pain
Time from cold exposure to rewarming
Provocation and palliation
Wet exposure
Wind exposure
Quality
Numbness
Burning pain after rewarming
Region and radiation
Digits
Ears
Severity
Functional loss
Pain score
Timing
Continuous symptoms after rewarming
Refreezing episodes
Exposure context
Ambient temperature estimate
Duration of exposure
Rewarming details
Rewarming already attempted
Refreezing risk after rewarming
Associated symptoms
Coexisting cold injury symptoms
Hypothermia symptoms
Confusion
Ataxia
Trauma symptoms
Falls
Immobilization time
Infection symptoms
Fever
Purulent drainage
Baseline and prior episodes
Baseline limb status
Baseline neuropathy
Diabetes related
Alcohol related
Prior frostbite
Prior amputations
Prior cold sensitivity
Alarm Features
Immediate threats
Time critical triggers
Systemic hypothermia suspected
Altered mental status
Core temperature low
Compartment syndrome concern
Pain out of proportion after rewarming
Tense swelling
Limb ischemia beyond frostbite
Absent Doppler signals proximal to injury
Rapidly progressive mottling
High risk frostbite features
Severe frostbite indicators
Hemorrhagic blisters
After rewarming
Proximal extent
Hard wooden tissue after rewarming
Proximal joint involvement
Circumferential involvement
Cyanosis not improving after rewarming
Persistent pallor
Non blanching skin
Vital sign danger thresholds
Physiologic instability
Hypotension
Shock physiology
Concern for sepsis or trauma
Bradycardia with hypothermia
Ventricular dysrhythmia risk
Rough handling risk
Medications
Current and recent meds
Medication exposure relevant to frostbite
Vasoconstrictive agents
Stimulants
Decongestants
Anticoagulants and antiplatelets
DOACs
Warfarin
Beta blockers
Blunted tachycardia response
Peripheral perfusion effects
Medication contraindications to therapies
Contraindication screen for thrombolysis and vasodilators
Thrombolysis contraindications
Recent intracranial hemorrhage history
Active bleeding
Vasodilator cautions
Hypotension
Severe aortic stenosis history
Diet
Recent intake and hydration
Nutrition and fluid status
Dehydration risk
Poor oral intake
Vomiting
Alcohol exposure
Intoxication during exposure
Withdrawal risk
Caffeine and energy drinks
High dose caffeine
Sympathomimetic additives
Review of Systems
General and infectious
System review targeted to complications
Constitutional
Fever
Chills
Skin
Spreading erythema
Foul odor
Cardiopulmonary and neurologic
Cold exposure complications
Cardiopulmonary
Chest pain
Dyspnea
Neurologic
Confusion
Syncope
Collateral History and Family History
Collateral source
Reliability and timeline support
Collateral informant
Companion on scene
EMS report
Exposure reconstruction
Last known well time
Duration outdoors estimate
Family history
Inherited and early vascular disease
Early cardiovascular disease
MI under age 55
Stroke under age 55
Thrombophilia history
VTE history in first degree relative
Known inherited thrombophilia
Risk Factors
Environmental and occupational
Exposure risk profile
High altitude exposure
Low ambient temperatures
Limited rescue access
Prolonged immobility
Intoxication
Entrapment
Inadequate insulation
Wet gloves or socks
Tight footwear
Patient factors
Host factors increasing risk and severity
Peripheral arterial disease (I73.9)
Claudication history
Prior revascularization
Diabetes mellitus (E11.9)
Neuropathy
Microvascular disease
Tobacco use
Current smoking
Recent nicotine use
Raynaud phenomenon (I73.00)
Cold induced color changes
Prior ischemic ulcers
Bleeding and thrombosis risk
Reperfusion and lysis decision context
Bleeding risk factors
Recent surgery
Known intracranial lesion
Thrombosis risk factors
Prior VTE
Estrogen therapy
Differential Diagnosis
Life threatening
Cannot miss diagnoses
Moderate to severe hypothermia (T68)
Bradycardia
Altered mental status
Sepsis from infected tissue (A41.9)
Fever
Hypotension
Compartment syndrome
Pain with passive stretch
Tense compartments
Acute arterial occlusion (I74.9)
Sudden pallor
Proximal pulse deficit
Common
Likely diagnoses
Frostnip
Reversible numbness
No blisters after rewarming
Superficial frostbite
Clear blisters
Erythema and edema after rewarming
Deep frostbite
Hemorrhagic blisters
Hard insensate tissue
Less common
Mimics and related cold injury
Pernio chilblains
Itchy erythematous papules
Subacute onset after cold damp exposure
Trench foot immersion foot
Prolonged wet exposure above freezing
Maceration and swelling
Cold contact injury
Localized area matching contact
Often sharply demarcated
Past Medical History
Conditions and prior care
Relevant comorbidities
Vascular disease history
Peripheral arterial disease
Prior amputations
Metabolic disease
Diabetes
Hypothyroidism (E03.9)
Psychiatric and substance use
Alcohol use disorder (F10.20)
Stimulant use
Surgeries and devices
Prior procedures affecting perfusion
Vascular interventions
Bypass grafts
Stents
Implanted devices
Pacemaker
ICD
Physical Exam
General and vitals
Initial assessment
General appearance
Toxic appearance
Shivering status
Vital signs
Temp
HR
Perfusion
Capillary refill proximal to injury
Skin temperature gradient
Extremity and skin exam
Frostbite staging bedside features
Pre rewarming findings
Pallor
Waxy skin
Post rewarming findings
Edema extent
Blister type
Demarcation
Circumferential involvement
Joint crossing
Neurovascular exam
Limb viability assessment
Pulses
Palpable pulses
Doppler signals
Sensation
Light touch
Two point discrimination
Motor
Active range of motion
Intrinsic hand or foot strength
Complication screen
High risk findings
Compartment syndrome
Pain with passive stretch
Tense compartments
Infection
Spreading erythema
Crepitus
Lab Studies
Core labs
Baseline and complication labs
CBC
Leukocytosis for infection
Thrombocytopenia for coagulopathy
Electrolytes
Potassium abnormalities
Renal function
Glucose
Hypoglycemia in exposure
Hyperglycemia and poor healing risk
Rhabdomyolysis and perfusion
Tissue injury evaluation
CK
Rhabdomyolysis screen
Trend with hydration response
Lactate
Shock marker
Severe hypoperfusion marker
Coagulation and thrombolysis readiness
Lysis and bleeding risk labs
INR
Warfarin effect
Baseline bleeding risk
aPTT
Heparin effect
Baseline bleeding risk
Fibrinogen
Baseline before thrombolysis
Trend during thrombolysis
Point of care testing
Bedside tests
Core temperature method
Esophageal probe if intubated
Rectal probe if not intubated
Blood gas if unstable
Acidemia severity
Ventilation status
Imaging
Scoring Systems
Frostbite severity grading for reperfusion therapy decisions
Cauchy classification
Grade 1
Grade 2
Cauchy classification
Grade 3
Grade 4
Application
Use after rewarming for blister and perfusion pattern
Higher grade supports iloprost or thrombolysis consideration
MRI
Limited role in acute frostbite
Indications
Suspected osteomyelitis later course
Deep space infection concern
Limitations
Early findings may not predict final tissue loss
Not first line for reperfusion decisions
CT
Complication focused CT
Indications
Trauma evaluation if fall or altered mental status
Gas in soft tissue concern
Contrast considerations
AKI risk with dehydration
Allergy history
Ultrasound
POCUS and vascular assessment
Doppler evaluation
Arterial signals
Venous thrombosis screen if swollen limb
Limitations
Distal digital flow may be difficult to assess
Does not replace angiography if lysis planned
Special Tests
Bedside rewarming response
Functional and perfusion response after rewarming
Return of sensation
Frostnip likelihood higher
Persistent anesthesia suggests deeper injury
Capillary refill
Improvement supports perfusion
Persistent no refill suggests severe injury
Advanced perfusion assessment
Specialist guided tests
Angiography
Candidate selection for intra arterial thrombolysis
Thrombosis visualization
Nuclear medicine bone scan
Tissue viability mapping around day 2 to 4
Surgical planning aid
ECG
Indications and key findings
Hypothermia and exposure ECG
Indications
Suspected hypothermia
Syncope during exposure
High risk findings
Osborn waves
Ventricular arrhythmias
Serial ECG and monitoring
Ongoing monitoring logic
Continuous telemetry
Moderate to severe hypothermia
Electrolyte abnormalities
Repeat ECG triggers
Temperature increases
Rhythm change
Assessment
Working diagnosis and severity
Frostbite classification summary
Frostnip versus frostbite
Reversible numbness without blistering
Persistent sensory loss with blistering
Superficial versus deep frostbite
Clear blisters
Hemorrhagic blisters
Severe frostbite suspicion
Perfusion deficit after rewarming
Proximal joint involvement
Complications to rule out
Associated problems and alternate diagnoses
Hypothermia severity
Core temperature category
Mental status category
Rhabdomyolysis
CK elevation
AKI risk
Infection
Cellulitis features
Necrotizing infection features
Plan
First 5 minutes
Immediate workflow
Monitoring
Continuous pulse oximetry if systemic exposure
Cardiac monitor if hypothermia suspected
IV access criteria
Moderate to severe hypothermia
Severe frostbite grade concern
Temperature management
Remove wet clothing
Warm environment and active external warming if hypothermic
Local frostbite care
Tissue protection and rewarming
Refreezing prevention
Do not rewarm if refreezing likely
Protect and insulate until definitive warming
Rapid rewarming when appropriate
Water bath 37 to 39 C
Rewarming until tissue pliable and erythematous
Mechanical precautions
No rubbing or massage
Avoid weight bearing on frostbitten foot if possible
Analgesia and anti inflammatory
Pain control and antithromboxane support
Opioid analgesia
Severe pain during rewarming
Titrate to effect with respiratory monitoring
Ibuprofen
Adult 400 to 600 mg PO every 6 to 8 hours
Max 2400 mg per day
Topical aloe vera
Apply to thawed tissue
Cover with sterile dressing
Blister and wound management
Local wound care strategy
Dressings
Loose bulky sterile dressings
Elevation to reduce edema
Blister management local protocol dependent
Clear blisters consider selective debridement in specialty care
Hemorrhagic blisters typically leave intact
Tetanus prophylaxis
Update per immunization status
Treat as wound
Reperfusion therapy and consultation
Severe frostbite limb salvage pathway
Early consult activation
Burn center or plastic surgery
Interventional radiology if thrombolysis pathway
Thrombolysis consideration
Perfusion deficit after rewarming
Presentation within 24 hours of rewarming
Iloprost consideration
Severe frostbite when thrombolysis contraindicated
Presentation within 48 to 72 hours of rewarming
Antibiotics and infection
Antimicrobial approach
Prophylactic antibiotics
Not routine for uncomplicated frostbite
Consider only with clear infection risk factors
Treatment antibiotics if infection
Cellulitis coverage per local protocol
Necrotizing infection requires broad spectrum and surgery
Reassessment loop
Time based reassessment
Recheck interval
Pain and perfusion reassess every 30 to 60 minutes early course
Neurovascular exam after rewarming completion
Escalation triggers
Worsening pain with tense swelling
Progressive perfusion loss
Disposition
Level of care and transfer
Admission and transfer criteria
ICU criteria
Moderate to severe hypothermia with instability
Ventricular dysrhythmia risk
Inpatient admission criteria
Deep frostbite with extensive tissue injury
Need for reperfusion therapy monitoring
Transfer to burn center criteria
Suspected deep frostbite grade 2 to 4
Perfusion deficit after rewarming
Discharge criteria
Safe discharge requirements
Low severity injury
Frostnip
Superficial injury without perfusion deficit
Pain controlled
Oral regimen effective
No uncontrolled rewarming pain
Reliable follow up
Wound check within 24 to 72 hours
Return precautions understood
Discharge Instructions
Copy discharge instructions
Frostbite discharge text
You had a cold injury that can worsen over the next several days even after rewarming
Keep the area clean, dry, elevated, and protected from cold
Do not rub the area and do not apply direct heat such as a heating pad
Use ibuprofen as directed unless you were told not to
Change dressings as instructed and keep blisters intact unless told otherwise
Return to the ED now for worsening pain, spreading redness, fever, pus, new numbness, black skin, or fingers or toes that become cold and pale again
Follow up in 1 to 3 days with the recommended clinic or burn service
Activity and prevention
Prevention focused guidance
Avoid refreezing
Do not go back into cold without adequate insulation
Keep gloves and socks dry
Activity limits
Limit walking on affected feet
Protect digits from trauma
References
Guidelines and key sources
Evidence based references
Wilderness Medical Society clinical practice guidelines for the prevention and treatment of frostbite 2019 update
Wilderness Medical Society clinical practice guidelines for the prevention and treatment of frostbite 2024
American Burn Association clinical practice guideline on severe frostbite treatment 2024
CMAJ Open management of severe frostbite with iloprost and alteplase 2021
AAFP frostbite recommendations for prevention and treatment summary of WMS guideline 2020
SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.