Cold Injuries: Frostbite and Hypothermia Michael White MD,FACS Director Detroit Receiving Hospital Wayne State University
Objectives of Talk Describe the incidence and characteristics of Frostbite injury Compare frostbite management with burn management Discuss current Standards of rewarming following hypothermia
FROST BITE
8 year experience of Cold Injury in Sweden
Who is at Risk for Frostbite Alcohol Consumption(46%) Psychiatric Illness(17%) Vehicular failure(19%) Drug misuse(4%) Homeless status JA Boswick et al Surg Gynecol Obstet1979;149:326-32
A grieve et al J R army Corps 157(1):73-78
R Nygaard et al J of burn Care Res 2018;89:780-785
Extremity Upper Lower Both NBR NTB 30% 0 48% 66% 15% 0 R Nygaard et al J of burn Care Res 2018;89:780-785
Injury Phase Stages of Local Cold Injury A Golant et al J Am Acad Orthop Surg 2008;16(12):704-715 Tissue Response Cooling and Freezing Rewarming Phase Progression of tissue Injury Resolution See vasoconstriction, as temperature drops may see Hunting response. Drop in temp to 28 C see ice crystals form lead to cell injury including endothelium.(exothermic Rxn) Endothermic Rxn that plateau at 28.Crystals melts. See intacellular swelling, endothelium most affected. Increased permeability leading to blistering and edema Inflammation, Vascular stasis, Thrombosis; Leads to tissue necrosis and blistering. Mediators include thromboxanes, Prostaglandins, platelet aggregating factors Tissue repair and wound healing vs tissue necrosis leading to gangrene
A Golant et al J Am Acad Orthop Surg 2008;16(12):704-715
Frostbite Injury
Frostbite Severity
Classification of Frostbite J Millet et al RG 2016;36(7):2154-2169
Recommendations for hospital Treatment of Frostbite: Wilderness Medicine Guidelines S McIntosh et al Wilderness and Enviromental Med 2014;25: S43-54
Wound care after thawing There is controversy on management of blisters: we open them. For superficial frostbite we use Dermaid Some centers will use Silvadiene for deeper burns We use triple and xeroform for wounds that are second degree and below. Most units will do daily hydrotherapy but there is no data that shows that is better
Diagnose Frostbite in Winter and Operate June
Multiphase Bone Scan Uses Tc-99 labeled disphosphonate Indicated for 2 nd, 3 rd, and 4 th degree Frostbite Perform 2-4 days after injury Predicts with over 84% accuracy level amputation May repeat 7 to 10 days after injury Presence of blisters cause increase in pooling contrast
J Millet et al RG 2016;36(7): 2154-2169
Example of Multiphase Bone Scans C Cauchy et al Eur J of Nucl Med 2000;27:497-502
SPEC/CT Scan for Evaluation of Frostbite Uses CT scan in conjunction with gamma camera to generate better anatomic images Performed in conjuction with multiphase bone scan Allows you to be able to tell level of bone viability anatomically
Patient with Deep Frostbite to hand Kraft et al J Burn Care Research 2017;38:e227-e234
DSA of Patient before and after 24 hrs of TPA J Millet et al RG 2016;36(7):497-502
Advantages to TPA for Severe Frostbite Showed significant limb salvage rate as high as 84% One study showed decreased length of stay Another option besides TPA is in use of Iloprost which is a analog of prostacyclin.
Management of Frostbite Multidisciplinary Management of these patients is beneficial Much like burns patients, these patients can require extensive wound care and need services provided by burn team. Treatment is evolving and no longer is just a wait and see what happens approach.
Hypothermia
Number of Cold Related Deaths in United States Age group 30-49 most commonly affected Average Number Deaths: 1306 deaths/year Males made up 67% of deaths
Mechanism of Heat Loss Normal Contribution(%) Exacerbating Factors Radiation (Non particulate emission of heat) 55 Vasodilators(Etoh, spinal cord injury) Evaporation (Cooling by conversion fluid to vapor) 25 Skin disorders(burns) Conduction (transmission of heat by direct contact) 15 25x increase in water Convection (Transmission of heat by movement of heated particles) minor 5x increase in windy conditions Respiratory(Evaporation) 5 Cold dry air
Predisposing Factors to Frostbite A Golant et al J Am Acad. Othop Surg:16:704-715
Progressive Hypothermia < 36 C-Shivering with increased cardiac output and ventilation < 34 C- Start to see decreased neurologic function <32 C- Increased risk of cardiac arrhythmia and cardiac arrest <30 C- Bradycardia and shivering ceases <28 C-Cardiac arrest and patient is unconscious G. Morrison et al Medicine 2017;45(3);135-138
Osborne Waves associated with Hypothermia S. Rahom et al Renal Failure2012;34(6):784-788
Hypothermia Swiss Classification Mild: 35 C to 32 C Moderate: 32 C to 28 C Severe < 28 C Profound <24 C K Zafren et al Wilderness and Enviromental Med 2014;25(4):425-445
Peter Paal et al Scand J of Trauma,Resusc, and Em Med 2016;24:111
Initial Assessment Use ATLS and ABC s to assess for traumatic injuries If severely depressed mental status may need intubation Pitfall: may see severe hypothermia Trismus that does not respond paralytics and may require fibro-opitc intubation or crycothyroidotomy. Patients usually will have some degree of hypovolemia Pitfall: Do not use lactated ringers for resuscitation secondary to inability to clear. If need central line recommend avoiding Internal Jugular or Subclavin Approach Labs on admission: electrolytes, blood gas with lactate, Coagulation studies, K Zafren et al Wilderness and Enviromental Med 2014;25: S66-S85 Peter Paal et al Scand J of Trauma,Resusc, and Em Med 2016;24:111
Measuring Core Temperature Esophageal probe temperatures most consistent with core temperature. Needs to be in distal esophagus Can use bladder and rectal temperatures but usually lag an hour behind changes in core temperatures Use of epitympanic thermometers. Will give accurate reading must have adequate blood flow to be reliable Peter Paal et al Scand J of Trauma,Resusc, and Em Med 2016;24:111
Class 1 Hypothermic Patients Usually manage with passive rewarming If patient does not respond then may need active rewarming measures.
Class II and Class III Hypothermia with an obtainable blood pressure Will need to employ active rewarming measures Will need ICU admission Will need some degree of resuscitation
Hypothermic Patient present with narrow complex rhythm and difficulty with feeling pulse Do not recommend CPR for these patients if they have evidence of spontaneous circulation Use Ultrasound to see if have cardiac function End tidal C02 measurement to see if they have a wave form Need resuscitation
Patients with hypothermia presenting in arrest. Patients will typically be in VT, Vfib and or Asystole These are the patients that are considered for Extracorporeal Life Support. CPR should be continued until they can be placed on ELS. Recommend using mechanical CPR device if available. Patients found with non reactive pupils and rigor mortis are not contraindications for resuscitation. ECMO is the ELS of choice, support patient until warmed to between 32-34 C. Can be used to support patient circulation if cardfiac function impaired. Can use cardiac bypass if that s what is available.
For Patients with VT or Vfib, at what temperature should you shock them? The guidelines are variable here The old dictum was you waited till after you warmed patient to 30 C. Found recommendations for defibrillating once below 30 C and if no response wait Another guideline stated could give up to three shocks below 30 C
Patients presenting with Temperature < 35 Celcius Gert-Jan Vander Pleeg et al Resuscitation;81:1550-1555
Comparison to asphyxiated vs non-asphyxiated Patients Asphyxiated Non-asphyxiated 2 patients in asphyxiated group had a good neurologic outcome 8 patients in non- asphyxiated group had a good neurologic outcome
Predictors of Poor outcome in patients who present in arrest and undergo ERCP Hyperkalemia> 10 mmol/l Central venous ph< 6.50 ACT time> 400 Ammonia > 250mmole/L Asphyxiation Cardiopulmonary arrest Hypothermia occurs indoors
Other Factors associated with Poor Outcome Advanced age Renal failure GCS < 5 Need for vasopressors Increased duration of exposure G. Morrison et al Medicine 2017;43(3):135-138
Management of Hypothermia Make sure to look for and identify early Look for potential trauma and follow ABC s Even patients in arrest have significant chance for good neurologic recovery using extracorporeal life support. Patients that present in CARDIAC ARREST should be sent to facility with either ECMO or cardiac bypass capability.