Medical Archive

Chapter 208: Cold Injuries 

Chapter 209: Hypothermia 

Chapter 210: Heat Emergencies 

Chapter 211: Bites and Stings 

Chapter 212: Snakebite 

Evaluation

Immobilization of the affected limb: the wound should be examined and marked for evidence of progression.

Appropriate laboratory studies: coagulation studies should be repeated at frequent intervals.

Management

• Crotalidae polyvalent immune Fab [Crofab]
  • Contains immunoglobulin fragments that bind to and neutralize cottonmouth, copperhead, and rattlesnake venom toxin.
  • Expensive, not always readily available, and carries a risk of significant allergic reactions and recurrent coagulopathy.
  • Administration of antivenom when indicated:
    • Unstable vital signs
    • Rapidly progressing changes in wound, or abnormal coagulation studies
• Observation
  • For 12-24 hours d/t the risk of delayed toxicity.
  • Repeat wound examinations and laboratory evaluation.

Chapter 213: Marine Trauma and Envenomation 

Chapter 214: Diving Disorders 

Chapter 215: Drowning 

Pediatric

https://hsnowhome.wpcomstaging.com/2020/03/13/p8-emergency-medicine-and-critical-care/

Chapter 216: High-Altitude Disorders 

Chapter 217: Thermal Burns 

Chapter 218: Chemical Burns 

Chapter 219: Electrical and Lightning Injuries 

Chapter 220: Mushroom Poisoning 

Chapter 221: Poisonous Plants 

Chapter 222: Carbon Monoxide

Epidemiology

• By smoke inhalation.
• In defective heating systems, gas motors operating in poorly ventilated areas.

Clinical manifestations

• Mild-moderate: headache, confusion, malaise, dizziness, nausea
• Severe: seizure, syncope, coma, MI, arrhythmias

Diagnosis

• ABGA: carboxyhemoglobin level (>3% in nonsmokers, >10% in smokers)
• Standard pulse oxymetry is unreliable and may appear normal b/c it cannot differentiate carboxyxhemoglobin from oxyhemoglobin.
• ECG +/- cardiac enzymes

Treatment

Patients should then be monitored (for >4 hours) and hospitatlized if their condittion has not improved.

Oxygen therapy

• Administer 100% oxygen immediately via nonrebreather facemask. 
  • To competet with CO binding to Hb and to decrease the half-life of CO (from ~5 hours on room air to 1-2 hours on 100% oxygen)
• Treatment endpoints 
  • Patient asymptomatic for at least 6 hours
  • COHb level normalizes (< 3–5%)

Hyperbaric oxygen therapy (HBOT)

• The benefits of hyperbaric oxygen have not been conclusively demonstrated. 
• The following are considered relative indications: 
  • COHb > 25%
  • Pregnant women with a COHb > 15%
  • Neurological manifestations (e.g., confusion, loss of consciousness, seizures, focal neurological deficits)
  • Acute myocardial ischemia
  • Severe acidosis (pH < 7.15)
  • Age > 35 years
  • Exposure ? 24 hours
  • Post-cardiac arrest

Management of systemic involvement and supportive care

• Secure airway: Consider early intubation in patients with inhalation injury or severely impaired mental status.
• Evidence of cardiac toxicity (e.g., arrhythmias, ischemia): urgent cardiology consult, continuous cardiac rhythm monitoring
• Metabolic acidosis:
  • Improve perfusion (e.g., fluids, oxygen).
  • Avoid sodium bicarbonate. 
• Pulmonology and toxicology consultations. 
• Suspicion of concomitant cyanide poisoning (see cyanide)
  • Administer hydroxocobalamin . 
  • Indications 
    • House fire as the source of CO toxicity
    • pH < 7.2
    • Lactate ? 10 mmol/L
• Suspicion of intentional poisoning
  • Evaluate for suicidal ideation 
  • Obtain a psychiatric consultation and consider involuntary psychiatric hold.