Burn Management PDF

Managing Burn Patients Hunter Speeg, DNP, CRNA Burns Overview From 2011-2015, 1.25 million sustained burn injuries in the US 3,390 died mainly from inhalation injuries in fires and crashes 75% of burn-related deaths occur at the accident scene 35% of burn victims are children (...

Managing Burn Patients Hunter Speeg, DNP, CRNA Burns Overview From 2011-2015, 1.25 million sustained burn injuries in the US 3,390 died mainly from inhalation injuries in fires and crashes 75% of burn-related deaths occur at the accident scene 35% of burn victims are children (60), >40% TBSA burns, and inhalation injury Early deaths ( 20% TBSA can lead to burn shock, impacting blood volume & CO Fluid resuscitation is essential to correct burn shock Initial Assessment (ABC + coexisting trauma) Rule out upper airway injury and/or head & neck burns (edema) Inhaled smoke can lead to pulmonary edema & V/Q mismatch Diagnosis & Assessment CXR, chest CT, etc. Treatment Upper airway injury → early intubation (even if no s/s decompensation) Fluid Resuscitation Guidelines Formula First 24 Hours Second 24 Hours Modified Brooke Crystalloid 2 mL LR / % burn / kg D5W Maintenance - Half in first 8 hr - Half in next 16 hr Colloid NONE 0.5 mL / % burn / kg Parkland Crystalloid 4 mL LR / % burn / kg D5W Maintenance - Half in first 8 hr - Half in next 16 hr Colloid NONE 0.5 mL / % burn / kg Fluid Resuscitation & UOP Consensus Formula Fluid Resuscitation Adults: LR 2-4 mL x kg body weight x %TBSA burned Pediatrics: LR 3-4 mL x kg body weight x % TBSA burned Note: ½ estimated volume in first 8 hr; second ½ over next 16 hrs Note: Infants and young children should receive IVF with 5% dextrose at maintenance rate in addition to resuscitation fluid Minimum UOP Adults: 0.5-1.0 mL/kg/hr Children < 30 kg: 1 mL/kg/hr High-voltage electrical injury: 1-1.5 mL/kg/hr Criteria for Adequate Fluid Resuscitation Normalization of blood pressure Urine output (1-2 mL/kg/hr) Blood lactate (< 2 mmol/L) Base deficit ( < -5 ) Gastric intramucosal pH ( > 7.32) Mixed venous oxygen tension (35-40 mmHg) Cardiac index (4.5 L/min/m2) Oxygen delivery index (DO2I) (600 mL/min/m2) Abdominal Compartment Syndrome ACS & IAH are causes of significant m & m in critically ill burn pt Secondary to aggressive fluid resuscitation IAP > 20 mmHg via transduction of bladder pressure + organ dysfunction HD instability, increased PIP, oliguria, worsening metabolic acidosis, etc. Treatment NMB, sedation, diuresis, laparotomy Fatal without treatment Perioperative Considerations Effective up-regulation of extrajunctional receptors AFTER 24 hours Succinylcholine safe within 24 hours of burn, but can cause hyperkalemia- induced cardiac arrest after 24 hours Dose requirement for NDMR increases by 2-5x Fluid shifts altering VOD Ketamine is a good analgesic, even in unstable patients Prevent hypothermia Inhalation Burns Inhalation injuries may accompany thermal burns and should be suspected Extent depends on fire location, ignition source, temp, & toxic gas concentration Four types of inhalation injuries based on anatomic location 1. Upper airway injuries (mouth, oropharynx, larynx) primarily from thermal injury 2. Lower airway injuries (trachea, bronchioles, alveoli) from smoke's chemical and particulate constituents 3. Pulmonary parenchymal injury 4. Metabolic asphyxiation or systemic toxicity (e.g., carbon monoxide or hydrogen cyanide) First priority = high FiO2 Gold standard for dx extent of injury = fiberoptic bronchoscopy Grading Scheme for Flexible Bronchoscopy Grade Findings Mortality (%) 0 Normal (no inhalational injury) 0 B Positive based on biopsy only 0 1 Hyperemia 2 2 Severe edema & hyperemia 15 3 Severe injury: ulcerations & necrosis 62 Lower Airway Injuries Arise from inhaling soot particles and chemicals produced by fire Inhaled toxins react with airway mucosa, forming acidic and alkaline substances that increase capillary permeability Extensive alveolar and epithelial damage can occur, leading to necrosis Warning signs of inhalation injury: Hoarseness, sore throat, dysphagia, hemoptysis, tachypnea, wheezing, carbonaceous sputum, elevated carbon monoxide levels Airway Management Abnormal or upper airway obstruction warrants awake FOI Topical anesthesia, positioning, supplemental oxygen, and incremental doses of ketamine or dexmedetomidine Sedatives should be administered judiciously to avoid worsening airway obstruction IV opioids may be appropriate for pain in alert patients Humidified inspired gases help clear tracheobronchial debris &prevent secretion drying ETT remains until laryngeal edema subsides Progressive air leak around the tube may indicate reduced edema Nebulized heparin and N-acetylcysteine reduce reintubation for pulmonary failure, atelectasis, and mortality Carbon Monoxide Poisoning CO binds to hgb with an affinity 200x that of oxygen Oxyhemoglobin dissociation curve shifts to the left (impaired O2 offloading) Anaerobic metabolism (no oxidative phosphorylation = metabolic acidosis) Blood has a "cherry red" appearance Dx requires measuring arterial COHgb levels via cooximeter Measures concentrations of all hgb moieties Pulse oximetry alone is inaccurate (may be falsely elevated) Treatment Half-life of COhgb is 26-148 min 100% FiO2 or hyperbaric oxygen Carbon Monoxide Poisoning Carboxyhemoglobin (%) Symptoms 0-10 Normal 10-20 Headache, confusion 20-40 Disorientation, fatigue, nasea, visual changes 40-60 Hallucination, combativeness, convulsion, coma, shock state 60-70 Coma, convulsions, weak respiration & pulse 70-80 Decreasing respiration and stopping 80-90 Death in < 1 hr 90-100 Death within a few minutes Cyanide Poisoning Cyanide is produced from combustion of plastics, foam, paints, wool, silk, etc. Binds to terminal cytochrome on electron transport chain, causing hypoxia, lactic acidosis, and elevated mixed venous oxygen saturation Half-life is ~ 1 hour Signs and Symptoms LOC, mydriasis, seizures, hypotension, tachypnea followed by apnea, & elevated lactate Treatment: Hydroxocobalamin 5g over 15 minutes Actively binds cyanide, forming cyanocobalamin, which is excreted by kidneys Rapid onset neutralizes cyanide without interfering with cellular oxygen use Preoperative Anesthesia Planning Warm OR ahead of time (28o-33oC) Check availability of blood products and order more if needed (based on preoperative hgb value, size of burn, & extent of debridement) Have blood products immediately available in OR Have at least one blood warmer primed, plugged in, & turned on If burn is large, have 2 Make sure that you have adequate IV access b/f surgeon begins debriding Know and plan ahead if invasive lines are needed Plan for airway management and ventilation both intraoperatively and postoperatively Have a plan but be willing to modify it if necessary Heat Loss in Burn Patients Source of Heat Loss Amount (%) Methods to ↓ Heat Loss Radiation 60 - Warm OR 28o-33o C - Heat lamps - Reflective blankets Evaporation 25 Warm OR Convection 12 Place pt on insulated or warming blanket Conduction 3 - Cover pt with watertight material - Humidify ventilator gases - IV fluid warmer - Forced air warming blanket References Nagelhout JJ, & Elisha, S. (2018) Nurse Anesthesia. 6th ed. St. Louis, MO. Elsevier Saunders