Exposure to Toxic Gases Flashcards
(27 cards)
The initial approach to any toxic inhalation
- First, scene safety in paramount
- Once the patient is safely accessible for the IDC, the mainstay of patient treatment is supportive care with
Inhaled agents manifest their toxic effects by four different mechanisms:
1) Physical particulates
2) Simple asphyxiants
3) Chemical irritants
4) Chemical asphyxiants
- Small, solid particles that are carried by gases or
atmospheric air into the body through inhalation (e.g., dust or combustion soot). - This situation is encountered most commonly with cases of smoke inhalation.
Physical Particulates
(c) Clinical symptoms of upper airway injury, such as difficulty breathing, might not be immediately obvious until edema is severe enough to significantly impair airway diameter.
(d) Symptoms of lower respiratory tract injury may include shortness of breath and productive cough
(e) Physical findings include burns to the face, signed nasal vibrissae, soot in the oropharynx, nasal passages, proximal airways, and carbonaceous sputum.
Physical particulate exposure
Treatment of physical particulate exposure
(a) Management is supportive:
1) Remove the patient from the source of the physical particulates and administer oxygen.
2) Patients with signs of reactive airway disease (e.g., wheezing and poor air flow) should be treated with nebulized Albuterol.
cause injury by merely being present in an environment and displacing the normal levels of atmospheric oxygen
Simple asphyxiants
Types of Simple asphyxiants
1) Carbon dioxide (CO2)
2) Nitrogen
3) Methane
4) Natural gas
How do simple asphyxiants affect the body
Simple asphyxiants have no inherent toxic or metabolic effect on the body’s cells,
other than causing hypoxia by default due to lack of adequate oxygen.
(a) Signs and symptoms depend on the agent involved and its concentration.
(b) Patients will exhibit such classic signs of hypoxia as agitation, which may rapidly
progress to unconsciousness and then cardiac arrest.
(c) If the asphyxiant is CO2, patients may experience a narcotic-like
sleepiness as the initial effect of exposure.
Simple Asphyxiants
Treatment of Simple Asphyxiants
(a) The mainstay of simple asphyxiant management is gaining safe access to the patient
(b) Administration of high-concentration oxygen
(c) Cardiopulmonary support as indicated
Express their toxic effects by chemical reaction with the mucus membranes of the eyes and respiratory system
Chemical irritants
Two general classes of chemical irritants
Hydrophilic and non-hydrophilic
Hydrophilic inhaled agents include
hydrochloric acid and ammonia.
Non-hydrophilic agents affect the body how
Don’t readily react with the moist membranes of the upper respiratory tract, they can pass more deeply
into the lungs and cause direct lung injury
Example of bib-hydrophilic chemical irritant
phosgene gas, a major industrial chemical used to make plastics and pesticides
Sx of non hydrophilic irritant
Sometimes these effect are delayed, and a patient may be relatively stable for a while and then decompensate with respiratory failure due to acute lung injury
Treatment of chemical irritant
(a) Treatment of chemical irritant exposures should include supportive care and irrigation of eyes with water or saline.
(b) As with particulate irritants, patients with underlying asthma or COPD will likely benefit from nebulized albuterol treatments if bronchospasm is evident during physical examination.
cause injury by asphyxiating patients at the
cellular level by massively deranging normal cellular utilization of oxygen
chemical asphyxiants
most common example of a chemical asphyxiant
carbon monoxide (CO).
Other examples of inhaled chemical asphyxiants
cyanide gas (HCN)
and Hydrogen Sulfide (H2S).
often has a gradual, even insidious, onset of symptoms, which may include headache, chest pain and decreasing mental status. Frequently, the patient
progresses to coma and death.
Carbon monoxide poisoning
Patients exposed to H2S and HCN tend to have
very rapid onset and progression of symptoms
treatment for CO poisoning
supportive care with high-flow oxygen via a
non-rebreather mask or ET tube for the comatose patient
What does hydrogen sulfide smell like
“Rotten eggs”
