This clinical practice guideline is intended to provide general advice for paramedics and EMRs/FRs managing toxic or chemical exposures where the substances involved can be classified as irritants, asphyxiants, acids, or alkalis. 

Separate practice guidelines exist for specific agents:

• → J02: Carbon Monoxide
• → J03: Cyanide
• → J04: Hydrogen Sulfide
• → J05: Organophosphates and Carbamates

• The safety of paramedics and EMRs/FRs is paramount.  Every patient’s need for decontamination must be carefully evaluated, and measures taken to control or eliminate ongoing contamination hazards.  Do not attempt to convey patients who have been insufficiently decontaminated. 
  • CliniCall consultation required prior to undertaking decontamination procedures.
• Under no circumstances will BCEHS paramedics or EMRs/FRs provide care in hot or warm zones.
• Avoid contaminating ambulances or downstream health care providers and facilities: ensure that an appropriate decontamination is completed prior to loading a patient for conveyance.  Downstream contamination can cause significant systemic disruption and must be avoided.
• Chemical exposures require a collaborative approach between agencies.  Paramedics and EMRs/FRs will need to rely on the expertise of other responders at these scenes.
• The vast majority of toxic or chemical exposures can be managed symptomatically.  Very few agents have specific out-of-hospital treatments.  Supportive basic care (airway control, support for oxygenation and ventilation, and management of hypotension) are often more important than antidote administration.
• Apply a staged approach to all aspects of management, including airway control.

In all cases of chemical exposure, consultation with CliniCall for decontamination requirements and care planning is required.  If there is uncertainty over the need for decontamination, the patient should undergo dry decontamination and then be re-assessed.  Collaborate with other providers on scene. 

Pulmonary Irritants

These agents primarily affect the respiratory tract and mucosal membranes.  They include industrial chemicals like chlorine, ammonia, and phosgene.  Mixing of household cleaning products, such as bleach and toilet bowl cleaners, can result in the production of irritant gases.  Their effects vary depending upon their solubility in water.  Upon contact with the mucosal membranes, they tend to dissociate into associated acids or bases, producing irritation.  Bronchospasm is common, and severe exposures can result in non-cardiogenic pulmonary edema.

Asphyxiants

Asphyxiants are primarily gases whose dangerous properties relate to their ability to displace oxygen from a space.  As the oxygen concentration falls, mental acuity among affected individuals begin to decrease while coordination and balance also decline.  Loss of consciousness occurs at concentrations below 10%, and death can occur quickly where oxygen concentrations are below 6%.  Patients who are removed from oxygen-deficient environments can be confused, agitated, combative, or comatose – all related to hypoxia.

Many asphyxiants have no warning properties such as taste, odour, or colour.  Some of these gases are flammable or explosive.  Examples include hydrogen, helium, ethane, ethylene, nitrogen, neon, carbon dioxide, argon, acetylene, methane, propane, and propylene.  Exposure to an asphyxiant does not generally require decontamination; where decontamination is required, dry decontamination and removal of clothing will generally suffice.  If patients are swiftly removed from an oxygen-deficient environment, recovery can be rapid; prolonged exposure to hypoxic environments can lead to irreversible end-organ damage.

Acids

Widely used in both household and industrial applications, acids can be found in products as diverse as toilet bowl cleaners, drain cleaners, metal polishes, electroplating solutions, descaling solutions, and battery fluid.  Exposure to acids generally involves splashes to the skin or into the eyes resulting in corrosive burns; ingestion of acid solutions or inhalation of acid fumes occurs occasionally. 

All patients who have been exposed to acids must be decontaminated.  The most effective method is to remove clothing and flush with copious amounts of running water.  Acids attack proteins in tissue, causing a coagulation necrosis and inflammation; airway compromise may occur and should be managed conservatively.  Bronchospasm should be treated as required. 

Alkalis

Like their acid counterparts, alkaline corrosives are found in numerous household and industrial products and processes.  Common examples include drain and oven cleaners, detergents, bleaches, and hair care products. “Lye” and “caustic soda” both refer to any strong alkali, generally either sodium hydroxide, potassium hydroxide, or a carbonate compound.  Alkaline corrosives disrupt the lipid membranes of tissues, causing significant damage.  As with other substances discussed in this guideline, the degree of damage depends heavily on the concentration of the substance, the duration of contact, and the total time of exposure. 

These patients must be decontaminated.  Brush off powdered material before removing clothes and flushing with water.  Skin may feel “soapy” during flushing; continue flushing until the soapiness subsides.  In cases of ingestion, and in consultation with CliniCall, consider giving 100-200 mL of milk or water to dilute the substance, but do not give in cases of nausea or vomiting. 

Supraglottic airway devices are contraindicated due to potential ingestion of caustic substances.