What is the workup for a patient with recent smoke fire exposure?

From the Guidelines

The workup for a patient with recent smoke fire exposure should begin with a thorough assessment of airway, breathing, and circulation, including measuring oxygen saturation, respiratory rate, and performing a focused physical examination, as well as obtaining arterial blood gas analysis and carboxyhemoglobin levels to evaluate for carbon monoxide poisoning 1. The initial evaluation should prioritize identifying signs of respiratory distress, such as wheezing, stridor, carbonaceous sputum, singed nasal hairs, or facial burns.

• Key components of the workup include:
  • Measuring oxygen saturation and respiratory rate
  • Performing a focused physical examination
  • Obtaining arterial blood gas analysis to assess for hypoxemia, hypercapnia, and metabolic acidosis
  • Measuring carboxyhemoglobin levels to evaluate for carbon monoxide poisoning, with levels above 10% in non-smokers or 15% in smokers indicating significant exposure 1
• Imaging studies, such as chest radiography, are essential to identify pulmonary infiltrates, pulmonary edema, or pneumothorax.
• Treatment with 100% oxygen via non-rebreather mask should be initiated immediately for patients with significant carbon monoxide exposure to reduce the half-life of carboxyhemoglobin from 4-5 hours to approximately 1 hour 1.
• Hyperbaric oxygen therapy may be considered for patients with severe poisoning, neurological symptoms, cardiac involvement, or pregnancy, although the evidence for its use is limited and controversial 1.
• Additionally, cyanide toxicity should be considered in enclosed-space fire victims, which may require treatment with hydroxocobalamin (Cyanokit) 5g IV over 15 minutes.
• Patients should be monitored for delayed complications, such as pulmonary edema, acute respiratory distress syndrome, and bronchiolitis obliterans, which can develop 24-48 hours after exposure.

From the Research

Workup for Recent Smoke Fire Exposure

The workup for a patient with recent smoke fire exposure involves a comprehensive approach to diagnose and manage potential injuries.

• Diagnosis is mostly clinical, aided by bronchoscopy and other supplementary tests 2, 3.
• Clinicians should maintain a high index of suspicion for concomitant traumatic injuries 2, 3.
• Treatment includes airway and respiratory support, lung protective ventilation, 100% oxygen or hyperbaric oxygen therapy for carbon monoxide poisoning, and hydroxocobalamin for cyanide toxicity 2, 3.

Diagnostic Approach

• A standardized diagnostic protocol for inhalation injury is lacking, and management remains mostly supportive 2, 3.
• Bronchoscopy and other supplementary tests can aid in diagnosis 2, 3.
• Clinicians should be aware of the potential for airway compromise and monitor patients closely 2, 3.

Treatment Options

• Inhaled anticoagulation regimens, such as nebulized heparin, may improve survival and decrease morbidity in patients with smoke inhalation-associated acute lung injury 4, 5.
• Nebulized heparin may improve oxygenation and reduce duration of mechanical ventilation in smoke inhalation injury, but may also increase the risk of pneumonia 5, 6.
• The use of N-acetylcysteine and albuterol in combination with heparin may be beneficial, but larger prospective studies are necessary to confirm efficacy and minimize infection risk 5, 6.