UTSW/BioTel Policy: Cyanide Antidote Administration

Purpose: The purpose of this policy is to allow for the administration of cyanide antidote to patients with suspected cyanide poisoning.

  1. Background:
    1. Cyanide
      1. Cyanide is a cellular toxin that inhibits mitochondrial cytochrome oxidase, thereby arresting cellular respiration. This results in severe metabolic acidosis, hemodynamic and respiratory collapse, and, ultimately, death. Symptom onset can be within minutes, depending on level of exposure.
    2. Hydroxocobalamin (Cyanokit®)
      1. Hydroxocobalamin binds to cyanide ions in the bloodstream, creating the cyanocobalamin molecule. Cyanocobalamin is in turn excreted into the urine.
  2. Signs/Symptoms:
    1. Signs and symptoms of cyanide toxicity can be grouped into three general categories, as follows.
    2. Mild symptoms
      1. Headache
      2. Tachypnea/dyspnea
      3. Flushing/diaphoresis
      4. Tachycardia
    3. Moderate symptoms
      1. Altered mental state
      2. Hypertension
      3. Respiratory depression
    4. Severe symptoms
      1. Seizure
      2. Cardiac arrest
      3. Cardiac arrhythmia
      4. Hemodynamic collapse / hypotension without other clear etiology
      5. Respiratory arrest
  3. Criteria for hydroxocobalamin administration:
    1. Hydroxocobalamin may be carried by, but not required of, the following units for administration:
      1. Battalion Commanders/Chiefs and EMS Chiefs/Supervisors
      2. Medical Directors
      3. HAZMAT
    2. Immediate administration
      1. Any patient with smoke inhalation or suspected cyanide ingestion/exposure AND the confirmed presence of cyanide on scene should be given hydroxocobalamin
      2. Any patient with smoke inhalation OR suspected cyanide ingestion and severe symptoms should be given hydroxocobalamin
    3. Administration in consultation with on-line medical control
      1. Any patient with smoke inhalation OR suspected cyanide toxicity and moderate symptoms may receive hydroxocobalamin in consultation with on-line medical direction
  4. Administration:
    1. Scene safety:
      1. Health care provider safety is paramount. Responders should not enter a scene where a potential exposure to cyanide may be encountered until cleared by appropriate agencies (fire, HazMat, etc.)
      2. If there is a suspected significant cyanide exposure, appropriate BSI and patient decontamination techniques should be observed
    2. Standard care, standard treatment guidelines:
      1. All patients should receive standard care commensurate with their condition. This includes, but is not limited to, seizure care, cardiopulmonary resuscitation, management of trauma, etc.
    3. Notification of EMS Administration:
      1. The paramedic administering hydroxocobalamin shall immediately notify his/her EMS Supervisor.
      2. The EMS Supervisor shall notify EMS Administration through the usual communication channels.
    4. Airway considerations:
      1. Pulse oximetry:
        1. Pulse oximetry in the patient suffering from cyanide toxicity may be unreliable.
        2. All patients with suspected cyanide toxicity should receive high-flow oxygen by tight fitting face mask.
      2. Carbon monoxide co-oximetry:
        1. If available, SpCO should be measured.
        2. This value should not be used to inform clinical decisions in the field, but may be useful to hospital providers.
      3. Quantitative end-tidal carbon dioxide (ETCO2):
        1. All patients being treated for cyanide toxicity should have continuous ETCO2 monitoring.
    5. Cardiac monitoring:
      1. All patients receiving treatment for cyanide toxicity should have continuous ECG monitoring.
    6. Glucose:
      1. All patients should receive capillary blood glucose analysis (BGA).
    7. Vascular access:
      1. Hydroxocobalamin administration requires a dedicated IV or IO line; as such, a second IV or IO access may be required.
    8. Dosing and administration:
      1. If the patient meets the above criteria for administration of hydroxocobalamin, dosing should be:
        1. 5 g for adults over 15 minutes.
        2. 70 mg/kg for pediatrics over 15 minutes.
        3. A second dose may be required if the patient is still symptomatic after 30 minutes.
          1. For pediatric patients, the second dose is half the first: 35 mg/kg over 15 minutes.
      2. The Cyanokit® comes in two 2.5g vials:
        1. Each vial should be reconstituted with 100 mL of sterile 0.9% sodium chloride (Normal Saline).
        2. If Normal Saline is unavailable, Ringer’s Lactate or 5% dextrose solutions may be used.
        3. After reconstitution, the vial should be gently rocked, not shaken, until no particulate matter exists and the solution is a dark red color.
  5. Additional considerations/medical control options:
    1. Refractory hypotension:
      1. Vasoactive medications should be given in consultation with on-line medical control.
    2. Discoloration of body fluids:
      1. Hydroxocobalamin will change the color of urine, sweat and tears to red. This is normal.  The provider, patient and onlookers should be made aware of this.