Smoke Inhalation & Thermal Injuries MODULE G3 Chapter 43: pp

Smoke Inhalation & Thermal Injury Fire related deaths are the third most common cause of accidental death in the US. Prognosis Extent and duration of smoke exposure. Chemical composition of the smoke. Size and depth of body surface burns. Temperature of gases inhaled. Age. Pre-existing health problems.

Anatomic Alterations Inhalation Thermal Injury. Steam Inhalation - rare Chemical Injury from toxic gas. Body surface burns.

Thermal Injury Inhalation of hot gases: Confined to the upper airway. Airways distal to the larynx are usually spared serious injury. Upper airways ability to cool hot gases. Reflex laryngospasm. Glottic closure.

Thermal Injury Acute upper airway obstruction. Occurs in 20-30% of cases. Supraglottic region. May rapidly develop after rapid IV fluid administration.

Chemical Injury Smoke Inhalation Damages the airway down to the alveoli. Substances in smoke are extremely caustic and poisonous to the body. COHB% Cyanide poisoning Formaldehyde Ammonia Sulfur dioxide

Medical Challenge Injury from burns can affect every organ system Multiple organ failure

Stages of Smoke Inhalation and Burns Early or Resuscitation Phase First 24 hours Intermediate Phase 2-5 days Late Phase After 5 days

Stage I CO Poisoning Affinity for the Hb is 200 – 250 times greater than oxygen. Left shift in the oxygen dissociation curve. Levels greater than 40% is severe exposure. P a O 2 may be normal or high. S a O 2 will be low – measure with co-oximeter. DO NOT USE A PULSE OXIMETER

Stage I Cyanide Poisoning Burning of polyurethane materials A cyanide blood level in excess of 1 mg/L is usually fatal Cyanide interferes with oxygen utilization in the mitochondria Anaerobic metabolism & lactic acidosis P a O 2 & S a O 2 can be normal

Stage I Tissue Hypoxia COHb poisoning (Anemic Hypoxia) Cyanide poisoning (Histotoxic Hypoxia) Metabolic acidosis

Stage I Thermal Injury Laryngospasm and glottic closure Airway obstruction Establish an airway Chemical Injury Inflammatory Response

Stage I Hypovolemic Shock Blood vessels become “Leaky” Massive fluid shift from the blood vessels into the tissues (third spacing) Generalized body edema Decreased Chest Wall Compliance Skin loses its elasticity Difficult to inflate the lungs

Stage I Hypermetabolic State Massive release of catecholamines from stress Nutrition is very important Patients need lots of calories VO 2 & VCO 2 increases Acute Lung Injury (ALI) Decreased P a O 2 /F I O 2 ratio..

Stage II Pulmonary Edema Decreased COP from loss of protein. Rapid infusion of fluids. ARDS Mechanical ventilation Stress induced hyperglycemia develops. Immune system becomes depressed. Infection sets in

Stage III Infections Pneumonia Sepsis and multi-organ failure DIC (Disseminated Intravascular Coagulation) Pulmonary embolism Long term effects Restrictive and Obstructive disorders Bronchiolitis Obliterans

Assessment Level of Consciousness Burns to face or upper airway Hoarseness Altered voice Painful swallowing Stridor Cherry red skin color Tachypneic Sputum Black, sooty White frothy Purulent (later finding) Nausea/vomiting Convulsions

Management Treat any unconscious or lethargic patient as a medical emergency. Suspect hypoxia. Intubate to protect the airway. 100 % oxygen &/or Hyperbaric Chamber P a O 2 in a hyperbaric may rise to 1,500 mm Hg Cyanide Poisoning Amyl nitrite, Sodium nitrite, Sodium thiosulfate

Management Fluid Administration Bronchoscopy Evaluate the extent of damage. Remove mucous plugs. Used for difficult intubations. CPAP with 100% oxygen Mechanical Ventilation Acute Respiratory failure or Acute Oxygenation failure

Management Analgesics for Pain FEED, FEED, FEED Steroids are controversial Aerosol Therapy Bronchodilators (B2 agonists) Mucolytics

Management Antibiotics Culture sputum, blood, wounds Prophylactic heparin therapy for PE Escharotomy Cutting of burned skin Help to treat the low compliance of the chest wall

Important Points Level of Consciousness Determine need for airway 100% Oxygen and Hyperbaric Chamber Never use Pulse Oximeter. Well maybe…