外科急诊创伤（英文）烧伤

BURNS Leaugeay Webre BS, CCEMT-P, NREMT-P Scenario Paramedic is called to the scene of a structure fire. FD has removed a victim from the house. BSI Scene safe 1 patient A/C standby FD/ PD on scene Now what? General Impression 33 yo male pt writhing in pain. Screams and begs for pain medication however poor historian. S- blistering to back and chest, R upper ventral area leg exposed muscle; eyebrows singed A- PCN, codeine M- none P- none L- earlier today E- woke up on fire A- B- C- Transport decision? % BSA burned? Tx? Objectives Describe the structure and function of skin Discuss the types of burns. Explain the degrees of thermal burns. Discuss causes and treatments of inhalation injuries. Identify methods of approximating burn injuries. Describe and apply treatment modalities for the burn patient. Burns, thermal. Escharotomy to release chest wall and allow for ventilation of the patient. Skin Largest organ of the body Anatomy Epidermis Dermis Subcutaneous tissue Layers lEpider mis lDermis lSubcut aneos lUnderly ing Structures lFas cia lNer ves lTe ndons lLig aments lMu scles lOrg ans Anatomy & Physiology of the Skin Function Protection Regulation Prevention Sensory Epidermis Outer, thinner layer Consists of dead keratinized cells Protects dehydration trauma light infection Dermis Gel like matrix Consists of collagen and elastin Contains blood vessels, lymphatics, sweat glands, hair follicles, sensory fibers Subcutaneous Connective tissue Adipose tissue cushioning insulation Causes Thermal Electrical Chemical Radiation Thermal Majority flame scald contact with hot objects Child with burns from a scald Determining Severity 1st degree 2nd degree 3rd degree (4th degree) Depth of Burn Superficial Burn Partial Thickness Burn Full Thickness Burn First Degree Superficial involve only epidermis Local pain and redness No blistering present Heal spontaneously 2-5 days without scarring Not included when calculating % TBSA Burn Depth Superficial Burn: 1st Degree Burn lSigns & Symptoms lRedde ned skin lPain at burn site lInvolve s only epidermis Second Degree Involve epidermis and dermis Partial thickness superficial partial thickness red, painful, blistered deep partial thickness pale, mottled Very painful Infection may evolve into 3rd degree Burn Depth Partial- Thickness Burn: 2nd Degree Burn lSigns & Symptoms lIntense pain lWhite to red skin lBlisters lInvolve s epidermis & dermis Third Degree Involve epidermis, dermis, subcutaneous tissue White, waxy, red, brown, leathery Dry and painless (muscle and bone) Burn Depth Full-Thickness Burn: 3rd Degree Burn lSigns & Symptoms lDry, leathery skin (white, dark brown, or charred) lLoss of sensation (little pain) lAll dermal layers/tissue may be involved Fourth Degree Include involvement of muscle and bone Charred in appearance Painless Pathophysiology Local changes- 111F produce injury Area of Damage Zone of coagulation Zone of stasis Zone of hyperemia Jacksons Theory of Thermal Wounds lZone of Coagulation lArea in a burn nearest the heat source that suffers the most damage as evidenced by clotted blood and thrombosed blood vessels lZone of Stasis lArea surrounding zone of coagulation characterized by decreased blood flow. lZone of Hyperemia lPeripheral area around burn that has an increased blood flow. Jacksons Theory of Thermal Wounds Zone of Hyperemia Zone of Stasis Zone of Coagulation Zone of Coagulation Central area of burn Necrotic from time of exposure Zone of Stasis Moderate degree of insult Decreased tissue perfusion Vascular damage/ leakage May progress to necrosis 24-48 hours Zone of Hyperemia Vasodilation Inflammation Viable tissue Bodys Response to Burns Emergent Phase (Stage 1) lPain response lCatecholamine release lTachycardia, Tachypnea, Mild Hypertension, Mild Anxiety Fluid Shift Phase (Stage 2) lLength 18-24 hours lBegins after Emergent Phase lReaches peak in 6-8 hours lDamaged cells initiate inflammatory response lIncreased blood flow to cells lShift of fluid from intravascular to extravascular space lMASSIVE EDEMA l“Leaky Capillaries Systemic Changes Massive release of inflammatory mediators Produce vasoconstriction/ dilation Increased capillary permeability Edema Fluid Shifts Initial decrease blood flow to burned area Followed by increased arterial vasodilation Release of vasoactive substance resulting in increased capillary permeability and edema Cardiovascular Loss of plasma volume Increased peripheral vascular resistance Decreased cardiac output decreased blood volume decreased venous return increased blood viscosity decreased contractility Renal Decrease circulating plasma Increase hematocrit Decreased CO decreased renal blood flow oliguria acute renal failure Gastrointestinal Decreased gastrointestinal blood flow Increased mucosal hemorrhage 20% ileus Immune System Depressed immune function 20% directly proportional to burn size sepsis Bodys Response to Burns Hypermetabolic Phase (Stage 3) lLast for days to weeks lLarge increase in the bodys need for nutrients as it repairs itself Resolution Phase (Stage 4) lScar formation lGeneral rehabilitation and progression to normal function Hypermetabolism Following severe burn and resuscitation tachycardia increased CO increased O2 demand massive proteolysis & lipolysis severe nitrogen loss Systemic Complications Hypothermia lDisruption of skin and its ability to thermoregulate Hypovolemia lShift in proteins, fluids, and electrolytes to the burned tissue lGeneral electrolyte imbalance Eschar lHard, leathery product of a deep full thickness burn lDead and denatured skin Systemic Complications Infection lGreatest risk of burn is infection Organ Failure lRelease of myoglobin Special Factors lAge & Health Physical Abuse lElderly, Infirm or Young Critical Burn Areas Face Hands Feet Groin Joints Circumfrential Inhalation Injuries Leading cause of death Closed space incident Presence of heavy smoke History of unconsciousness Burns, thermal. Partial- and full-thickness burns from structure fire. Note facial involvement. Inhalation Injury Toxic Inhalation lSynthetic resin combustion lCyanide & Hydrogen Sulfide lSystemic poisoning lMore frequent than thermal inhalation burn Carbon Monoxide Poisoning lColorless, odorless, tasteless gas lByproduct of incomplete combustion of carbon products lSuspect with faulty heating unit l200x greater affinity for hemoglobin than oxygen lHypoxemia & Hypercarbia Other Evidence Facial burns Profuse secretions Carbonaceous sputum Lacrimation Singed nasal hair Hoarseness Wheezing Stridor Edema Hypoxemia Tachycardia Inhalation Injury Airway Thermal Burn lSupraglottic structures absorb heat and prevent lower airway burns lMoist mucosa lining the upper airway lInjury is common from superheated steam lRisk Factors lStanding in the burn environment lScreaming or yelling in the burn environment lTrapped in a closed burn environment lSymptoms lStridor or “Crowing” inspiratory sounds lSinged facial and nasal hair lBlack sputum or facial burns lProgressive respiratory obstruction and arrest due to swelling Types of Injuries Carbon monoxide poisoning Injury above glottis Injury below glottis CO Poisoning Affinity for Hgb 200-250X than O2 Cherry red only present at levels 40% +N,+V, HA, decreased LOC, weakness, tachypnea, tachycardia False pulse oximetry reading 100% O2 time for elimination 40 min 21% O2 time elimination 250 minutes Carboxyhemoglobin Normal- 0 Smokers, truck drivers in heavy traffic- 15 15-40%- neurological dysfunction weakness, dizziness, +N, +V, HA 40-60%- obtunded severe decreased LOC Consider hyperbaric therapy- 25-40% Injury Above Glottis Thermal, chemical Require early intubation Severely hypovolemic Injury Below Glottis Usually chemical Repiratory distress Require early intubation ARDS MSOF Estimating % BSA Burned Rule of palms Rule of nines Body Surface Area Rule of Nines lBest used for large surface areas lExpedient tool to measure extent of burn Rule of Palms lBest used for burns 10% 50 2nd/3rd degree burns 20% TBSA 2nd/3rd degree burns to critical areas 3rd degree 5% TBSA Significant electrical/ chemical burns Inhalation injury Circumfrential burns Preexisiting conditions medical or concomitant trauma Scene Size-up lFire Department lSCBA and protective clothing Initial Assessment lABCs MUST be intact lConsider ET or RSI lRapid evacuation of patient if scene is unstable Assessment of Thermal Burns Focused and Rapid Trauma Assessment lAccurately approximate extent of burn injury lRule of Nines or Rule of Palms lDepth of burn lArea of body effected lAny burn to the face, hands, feet, joints or genitalia is considered a serious burn l“Ringing” burns lAge of patient affected Assessment of Thermal Burns Pain Changes in skin condition at affected site Adventitious sounds Blisters Sloughing of skin Hoarseness Dysphagia Dysphasia Assessment of Thermal Burns General Signs & Symptoms Burnt hair Edema Paresthesia Hemorrhage Other soft tissue injury Musculoskeletal injury Dyspnea Chest pain Assessment of Thermal Burns Any partial or full thickness burn involving hands, feet, joints, face, or genitalia 30% BSAPartial Thickness Inhalation Injury 10% BSAFull Thickness Critical 2% BSAFull Thickness 50% BSASuperficial 15% BSAPartial Thickness Moderate Minor Burn SeverityBurn Severity Ongoing Assessment lNon-critical: Reassess Q 15 min lCritical: Reassess Q 5 min Burn Center Care Assessment of Thermal Burns Local & Minor Burns lLocal cooling lPartial thickness: 15% BSA lFull thickness: 5% BSA lMaintain warmth lPrevent hypothermia lConsider aggressive fluid therapy lModerate to severe burns lBurns over IV sites lPlace IV in partial thickness burn site. Management of Thermal Burns Parkland Burn Formula 4 mL x Pt wt in kg x % BSA = Amt of fluid lPt should receive of this amount in first 8 hrs. lRemainder in 16 hrs lConsider 1 hour dose l0.5ml x Pt wt in kg x % BSA = Amt of fluid Management of Thermal Burns Moderate to Severe Burns lCaution for fluid overload lFrequent auscultation of breath sounds lConsider analgesic for pain lMorphine lNubain lPrevent infection Management of Thermal Burns Inhalation Injury lProvide high-flow O2 by NRB lConsider intubation if swelling lConsider hyperbaric oxygen therapy lCyanide Exposure lSodium Nitrite, Amyl Nitrite, Sodium Thiosulfate lForms methemoglobin binds to cyanide lNon-toxic substance secreted in urine lInhale 1 ampule of Amyl Nitrite l300 mg Sodium Nitrite over 2-4 minutes l12.5 gm of Sodium Thiosulfate Management of Thermal Burns Scenario Lightning Injuries One of the top three causes of environmental death (flood, temp extremes) Not AC or DC but a unidirectional, massive, current impulse with several return strokes back to the cloud Tremendously large current impulsively flows for an incredibly short time Difference Between Lightning and Electricity Duration of exposure to current lNot enough time for skin burns lInternal burns and renal failure usually inconsequential Cardiac arrest Respiratory arrest Vascular spasm Neurological damage Immediate Ventricular asystole lOften spontaneously resume Prolonged respiratory arrest lResults in secondary cardiac arrest Ischemia due to vascular spasms lMI, spinal artery syndromes Long Term Survivors 10-20x fatalities Neuropsychological and neurocognitive changes Chronic pain syndromes Chest pain Sympathetic nerve system dysfunction Sleep disorders, HA, cardiac effects Demographics Sunday, Saturday, Wednesday Noon- 6pm, 6- 12 pm May be in or outdoors Males, 10 miles from thunderstorm, clouds/ rain may not be present Shelter- school buses, metal top vehicles lAvoid trees, small shelters, bleachers, fences, towers, any current transmitting structures, pools/ water, high areas lAvoid use telephones, electronic equipment, any contact with conductive surfaces inside (plumbing, doing dishes), EMS/ fire dispatch radio Arcing electrical burns, through shoe around rubber sole. High- voltage (7600 V) alternating current Electrical Age related injury peaks infancy-4 years 20-25 year old males- primarily work related Factors Affecting Severity Voltage and amperage Resistance of body tissue Type and path of current Duration and intensity of contact Electrical Burns Terminology lVoltage lDifference of electrical potential between two points lDifferent concentrations of electrons lAmperes lStrength of electrical current lResistance (Ohms) lOpposition to electrical flow Electrical Burns Ohms Law V: Voltage R: Resistance I: Current Based on electron flow thru Tungsten lEmit more light the more current passed thru Electrical Burns Joules Law P: Power Skin is resistant to electrical flow lGreater the current the greater the flow thru the body and greater the release of heat Electrical Burns Greatest heat occurs at the points of resistance lEntrance and Exit wounds lDry skin = Greater resistance lWet Skin = Less resistance Longer the contact, the greater the potential of injury lIncreased damage inside body Smaller the point of contact, the more concentrated the energy, the greater the injury Electrical Burns Electrical Current Flow lTissue of Less Resistance lBlood vessels lNerve lTissue of Greater Resistance lMuscle lBone Results in lSerious vascular and nervous injury lImmobilization of muscles lFlash burns Voltage High 1000 volts Low resistance injury Complications Cardiac arrythmias Respiratory muscle paralysis Thrombosis Renal failure Fractures DC- direct current discrete exit AC-alternating current more explosive Current Passage Mortality Hand to hand- 60% Hand to foot- 20% Foot to foot- 5% Special Considerations Respiratory Cardiac Concomitant trauma Renal failure Require fluid resuscitation Electrical Injuries lSafety lTurn off power lEnergized lines act as whips lEstablish a safety zone lLightning Strikes lHigh voltage, high current, high energy lLasts fraction of a second lNo danger of electrical shock to EMS Assessment & Management of Electrical and Lightning Injuries lAssess patient lEntrance & Exit wounds lRemove clothing, jewelry, and leather items lTreat any visible injuries lThermal burns lECG monitoring lBradycardia, Tachycardia, VF or Asystole lACLS Protocols lTreat cardiac & respiratory arrest lAggressive airway, ventilation, and circulatory management. lConsider Fluid bolus for serious burns l20 ml/kg lConsider Sodium Bicarbonate: 1 mEq/kg lConsider Mannitol: 10 g Assessment & Management of Electrical Injuries Contact electrical burns, 120-V alternating current nominal. The right knee was the energized side Chemical Strong acids coagulation necrosis Strong bases liquefication necrosis Will continue burning until neutralized or diluted Degree of Damage/Toxicity Chemical nature Amount Concentration Mechanism Duration Chemical Burns Chemical destroys tissue lAcids lForm a thick, insoluble mass where they contact tissue. lCoagulation necrosis lLimits burn damage lAlkalis lDestroy cell membrane through liquefaction necrosis lDeeper tissue penetration and deeper burns Oral caustic chemical burns Strong Acids and Alkalis Strong acids and alkalis may cause burns to the mouth, pharynx, esophagus, and sometimes the upper respiratory and GI tracts Ingestions of caustic and corrosive substances generally produce immediate damage to the mucous membrane and the intestinal tract lAcids generally complete their damage within 1 to 2 minutes after exposure lAlkalis, particularly solid alkalis, may continue to cause liquefaction of tissue and damage for minutes to hours Alkali burn to eye Signs and Symptoms Facial burns Pain in the lips, tongue, throat, or gums Drooling, trouble swallowing Hoarseness, stridor, shortness of breath Shock secondary to bleeding or vomiting Management Establish an airway, consider intubation, or if necessary, cricothyrotomy Contact poison control Gastric lavage or charcoal often contraindicated IV with NS or LR Rapid transport Hydrocarbons A group of saturated and unsaturated compounds derived primarily from crude oil, coal, or plant substances lFound in many household products and in petroleum distillates Hydrocarbons Viscosity is the most important physical characteristic in potential toxicity lThe lower the viscosity, the higher the risk of aspiration and associated complications Clinical features of hydrocarbon ingestion vary widely, depending on the type of agent involved lMay be immediate or delayed in onset Signs and Symptoms Burns due to local contact Wheezing, dyspnea, hypoxia, and pneumonitis due to aspiration or inhalation Headache, dizziness, slurred speech, ataxia (irregular or difficult-to-control movements), and dulled reflexes Foot and wrist drop with numbness and tingling Cardiac dysrhythmias Management Most are not life-threatening Occasionally gastric lavage may be of benefit In seriously symptomatic patients, protect the airway and establish an IV if NS or LR Contact poison control Transport Chemical Burns lScene size-up lHazardous materials team lEstablish hot, warm and cold zones lPrevent personnel exposure from chemical lSpecific Chemicals lPhenol lDry Lime lSodium lRiot Control Agents Assessment & Management of Chemical Burns Specific Chemicals lPhenol lIndustrial cleaner lAlcohol dissolves Phenol lIrrigate with copious amounts of water lDry Lime lStrong corrosive that reacts with water lBrush off dry substance lIrrigate with copious amounts of cool water lPrevents reaction with patient tissues Assessment & Management of Chemical Burns Sodium lUnstable metal lReacts vigorously with water lReleases lExtreme heat lHydrogen gas lIgnition lDecontaminate: Brush off dry chemical lCover the wound with oil subst