Cyanide Exposure

Table of Contents

Aliases

Cyanide, hydrogen cyanide, blood agent

Patient Care Goals

  1. Remove patient from toxic environment
  2. Assure adequate ventilation, oxygenation and correction of hypoperfusion

Patient Presentation

Cyanide is a colorless, “bitter almond smell” (genetically only 40% of population can smell) gas or white crystal which binds to the ferric ion in cells, blocking the enzyme cytochrome oxidase, thus preventing the use of oxygen by the cell’s mitochondria, leading to cellular hypoxia.

Inclusion Criteria

  1. Depending on its form, cyanide can enter the body through inhalation, ingestion, or absorption through the skin. Cyanide should be suspected in occupational or other smoke exposures (e.g. firefighting), industrial accidents, natural catastrophes, suicide and murder attempts, chemical warfare and terrorism (whenever there are multiple casualties of an unclear etiology). Non-specific and early signs of cyanide exposure (inhalation, ingestion, or ab­sorption) include the following signs and symptoms: anxiety, vertigo, weakness, headache, tachypnea, nausea, dyspnea, vomiting, and tachycardia
  2. High concentrations of cyanide will produce:
    1. Markedly altered level of consciousness, including rapid collapse
    2. Seizures
    3. Respiratory depression or respiratory arrest
    4. Cardiac dysrhythmias (other than sinus tachycardia)
  3. The rapidity of onset is related to the severity of exposure (inhalation or ingestion) and may be dramatic with immediate effects that include early hypertension with subsequent hypotension, sudden cardiovascular collapse or seizure/coma, and rapid death

Exclusion Criteria

No recommendations

Patient Management

Assessment

  1. Remove patient from toxic environment
  2. Assess ABCDs and, if indicated, expose the patient, and then re-cover the patient to assure retention of body heat
  3. Assess vital signs including temperature and pulse oximetry (which may not correlate with tissue oxygenation in cyanide/smoke exposure)
  4. Attach a cardiac monitor and examine rhythm strip for arrhythmias
    1. Perform a 12-lead EKG
  5. Check blood glucose level
  6. Monitor pulse oximetry and ETCO2
  7. Monitor patient for signs of hypoxia (pulse oximetry 94%) and respiratory decompensation regardless of pulse oximetry reading
  8. Identify the specific agent of exposure, time of ingestion/inhalation, and quantity/timing of exposure
  9. Obtain patient history including cardiovascular history and prescribed medication
  10. Obtain other pertinent patient history
  11. Perform physical exam

Treatment and Interventions

There is no widely available, rapid, confirmatory cyanide blood test. Many hospitals will not be able to rapidly assess cyanide levels. Therefore, treatment decisions must be made on the basis of clinical history and signs and symptoms of cyanide intoxication. For the patient with an appropriate history and manifesting one or more significant cyanide exposure signs or symptoms, treat with:

  1. 100% oxygen via non-rebreather mask or bag valve mask
  2. Administer one of the following medication regimes
    1. Adult: Administer hydroxocobalamin (Cyanokit)
      1. Initial dose is 5 g administered over 15 minutes slow IV
      2. Each 5 g vial of hydroxocobalamin for injection is to be reconstituted with 200 mL of LR, NS or D5W (25 mg/mL) and administered at 10-15 mL/minute
      3. An additional 5 g dose may be administered with medical consultation.
    2. Pediatric: Administer hydroxocobalamin (Cyanokit) 70 mg/kg (reconstitute concentration is 25 mg/mL)
      1. Each 5 g vial of hydroxocobalamin for injection is to be reconstituted with 200 mL of LR, NS or D5W (25 mg/mL) and administered at 10-15 mL/minute
        1. 70 mg/kg = 2.8 mL/kg
      2. Maximum single dose is 5 g
    3. If seizure, treat per Seizures guideline

Notes – Cyanide Exposure