Burns

BURNS

RAY RISNER C. OBENZA, MD, FPCS, FPSGS

EPIDEMIOLOGY • Quality of Burn Care Survival Long-term Function Appearance Surgeon’s Goal Well-healed, durable skin with normal function and near-normal appearance

BURNS *Depth of Injury is directly proportional to: Temperature applied Duration of contact Thickness of the skin

ETIOLOGY 1. Scald Burns - usually household from hot water - most common among civilians injuries especially children 2. Flame Burns - 2nd most common mechanism - secondary to house fires, MVA

ETIOLOGY 3. Flash Burns - explosion of gases & other combustible liquids - covers larger TBSA - with thermal damage to upper airway 4. Contact Burns - contact with hot metals, plastics, glass - common in industrial accidents - often 4th degree

ETIOLOGY 5. Electrical Burns - either occupational or household injuries - severity based on voltage, duration of contact & resistance of the patient 6. Chemical Burns - due to strong acids or alkalis - industrial accidents or assaults

PHASES OF BURN INJURY • Acute

Phase

Fluids & Electrolytes Pain Control Burn Wound Care & Coverage Septic Complications Nutritional Management

PHASES OF BURN INJURY • Chronic Phase Rehabilitation Reconstruction Psychological Support

• Pathophysiology of Burn Injury 1. Coagulation Necrosis 2. Increased Capillary Permeability 3. Hemolysis

ACUTE PHASE • Immediate Care Rescue and First Aid = on scene - remove source of heat - CPR if necessary; O2 inhalation

Assessment and Resuscitation = at the ER - ABC’s take priority - Intubation if necessary

Preparation for transfer to a burn facility - for burns more than 5 – 10% TBSA

• Immediate first aid measures Cooling the burned area - application of cool water NOT iced water

Removal of patient’s clothing - remove source of heat & exposure of injuries

Prevention of hypothermia - wrap patient in clean blanket

• Admission Criteria to a Burn Facility Partial Thickness Burns =/> 15% Full Thickness Burns =/> 5% Burns on Face, Feet, Hands & Perineum All Electrical & Chemical Burns Presence of Smoke Inhalation Injury Associated Injuries

• Admission Criteria Child Abuse Patients <10 y.o. & >50 y.o. Patients w/ Associated medical illness All infected burns Dependent persons

• Determinant Factors for Mortality 1. Age of the patient 2. Burn size 3. Smoke Inhalation Injury

• Patient Assessment 1. History Time of Injury Place of Injury Mechanism of Injury 2. Physical Exam Primary Survey = ABC’s 2ndary Survey = Other injuries

• Estimation of Burn Injury Severity Burn Size: Rule of Nines = massive burns Patient’s Palm = patchy burns Lund-Browder Chart = pediatrics

• “Rule of Nines” for estimating TBSA Anatomic Area Head Rt. Upper extremity Lt. Upper extremity Rt. Lower extremity Lt. Lower extremity Anterior trunk Posterior trunk Perineum

% body surface 9 9 9 18 18 18 18 1

Estimation of Burn Injury Severity Burn Depth is dependent on: a. Temperature of burn source b. Thickness of the skin c. Duration of contact d. Heat dissipating capability of skin

Classification of Burn Depth 1. Shallow Burns a) Epidermal Burns (1st Degree Burns) - do not blister but erythematous - relatively painful ex. Sunburn

b) Superficial PartialThickness Burns (2nd Degree Burns) -

form blisters, pink & wet hypersensitive to pain blanch with pressure spontaneously heal < 3 weeks

Classification of Burn Depth 2. Deep Burns a) Deep Partial-Thickness Burns (2nd Degree) - blisters, mottled pink and white - capillary refill is slow to absent - less sensitive to pain - heals in 3 to 9 weeks

b) Full Thickness Burns (3rd Degree) - all layers of dermis - leathery, dry white, firm & insensate - develop “ESCHAR” - heal by contracture or skin grafting

c) Fourth Degree Burns - full thickness skin, SQ fat, fascia & muscles - electrical, contact, immersion burns in an unconscious patient

Assessment of Burn Depth Methods: 1. Clinical observation – only 70% accurate 2. Detection of Dead cells or denatured collagen - biopsy, ultrasound, use of vital dyes

3. Assessment of Change in Blood Flow

- fluorometry, laser Doppler, thermography

4. Analysis of Wound Color

- light reflectance method

5. Evaluation of Physical Changes - magnetic resonance imaging

Physiologic Response to Burn Injury SYSTEMIC INFLAMMATORY RESPONSE SYNDROME (SIRS) - pathologic alterations in metabolic, cardiovascular, gastrointestinal and coagulation systems - hypermetabolism, increased cellular, endothelial & epithelial permeability - extensive microthrombosis

Physiologic Response to Burn Injury BURN SHOCK - circulatory dysfunction - increase in vascular permeability & microvascular hydrostatic pressure Mediators: 1. Histamine – release mast cells which disrupts venular endothelial junctions 2. Serotonin – increase pulmonary vascular resistance 3. Eicosanoids – increase levels of vasodilator PG’s

• Diagnostic Work-up Complete Blood Count Urinalysis, BUN & Serum Creatinine Baseline electrolytes Arterial blood gas determination X-rays (Chest, other areas) Electrocardiography Etc

• Fluid Resuscitation Recommended Fluids: Plain Lactated Ringer’s Solution = 1st 24 hours Colloids or D5Water = after 24 hours

• Fluid Computation & Administration a) 1st 24 hours

“Parkland Formula” TFR = BW x TBSA x 4 mg/kg/%burns (1/2 given in1st 8H; 1/2 next 16H)

b) 2nd 24 hours

D5W replace evaporative losses Colloids maintain plasma volume

c) After 48 hours

Maintenance Fluids = 30-40 cc/kg/day

• Parameters for Monitoring Fluid Therapy 1. Urine Output Adults: 0.5 cc/kg/hour Pedia : 1 cc/kg/hour 2. Vital Signs Blood pressure & Heart rate Central Venous Pressure 3. Sensorium

• Reasons for Failed Resuscitation 1. Delayed resuscitation 2. Presence of electrical burns 3. Smoke inhalation injury 4. Coronary artery disease

Ancillary Management Measures 1. Gastric decompression 2. Pain control & sedation 3. Antibiotics 4. Tetanus prophylaxis

Compartment Syndrome a) Clinical Manifestations 6 P’s: Pulselessness Pallor Pain

Paresis/Paralysis Paresthesia Poikilothermia

b) Definitive Treatment: ESCHAROTOMY FASCIOTOMY

Inhalation Injury 1. Carbon Monoxide Poisoning Effects: a) prevents reversible displacement of O2 b) decrease O2 unloading at tissue level c) less effective intracellular respiration d) directly toxic to cardiac & skeletal muscles Treatment: Hyperbaric Oxygen ???

Inhalation Injury 2. Thermal Airway Injury Manifestations: - mucosal & submucosal erythema - edema, hemorrhage & ulceration - potential for upper airway obstruction Treatment: Endotracheal Intubation

Inhalation Injury 3. Smoke Inhalation Factors: a) Type and amount of smoke inhaled b) Size of particulates c) Duration of Toxic Exposure d) Magnitude of thermal injury Clinical Manifestations: a) dyspnea b) burned vibrissae c) carbonaceous sputum

Inhalation Injury Diagnosis:

a) Chest X-ray b) Bronchoscopy c) Arterial blood gas

Management: a) Endotracheal intubation b) Mechanical ventilation

Electrical Burns Classification: Low voltage: <1,000 volts High voltage: >1,000 volts Mechanisms of injury: a) Direct contact b) Conduction arc c) Secondary ignition

Electrical Burns Physiologic Alterations: a) Arrhythmias b) Acute Renal Failure c) CNS & PNS Deficits d) Hemorrhage & Hematomas

Chemical Burns Factors to consider: a) Contact time b) Chemical involved Primary Management: Rapid termination of burning process

Burn Wound Care Salient Aspects: Debridement of necrotic tissue Daily dressing of burn wound Surgical Management: a) Tangential excision b) Fascial excision

Burn Wound Care Topical Antimicrobials a) Aqueous silver nitrate b) Mafenide acetate c) Silver sulfadiazine d) Povidone-iodine

Nutritional Support State of hypermetabolism - exaggerated energy expenditure - massive nitrogen loss Formula: TCR = 25 kcal/kg BW + 40 kcal/%TBSA Route: Total Enteral Nutrition (TEN) Adv: maintain integrity of GI tract reduce bacterial translocation & sepsis

Burn Wound Infection Clinical Manifestations 1. Conversion from partial to full thickness 2. Dark-brown/blackish discoloration 3. Neo-eschar formation 4. Rapid eschar separation 5. Violaceous wound margins 6. Metastatic septic lesions

Burn Complications A) Distant infections 1. Pneumonia 2. Bacterial Endocariditis 3. Urinary Tract Infection 4. Suppurative chondritis 5. Vascular Catheter-Related Infection

Burn Complications B) Other complications 1. Curling’s ulcer 2. Acute Acalculous Cholecystitis 3. Myocardial Infarction

Burn Wound Coverage a) Temporary 1. Biologic wound coverings Allograft Xenograft Amnion 2. Hydrocolloid dressings

Burn Wound Coverage b) Permanent 1. Skin Grafting a) Split-thickness b) Full-thickness

2. Skin Flaps 3. Skin Substitutes a) AlloDerm b) INTEGRA

4. Cultured Skin a) Apligraf b) Epicel

Chronic Phase 1. Rehabilitation:

Range of motion exercises Ambulation training Return to functional status

2. Psychological Support: Anxiety, Depression, Denial Withdrawal, Regression

Chronic Phase 3. Reconstruction: Burn contractures Keloids Hypertrophic scars Marjolin’s ulcer