Decontamination, Elimination, Antidotes Flashcards
What is decontamination?
Why it is used? (3 total)
- Stop ongoing exposure - no longer in direct contact with the patient
- To prevent absorption
- Decrease the possiblity of transfer of the toxic substance to health care workers
What are 3 principles of GI decontamination to know?
- If a patient is already symptomatic, it means absorption has occurred and decontamination is unlikely to be of benefit- its efficacy decreases with time.
- Prioritize airway protection and provide symptomatic and supportive care (ABCs).
- Risk vs. benefit of GI decontamination is largely dependent on severity of potential toxicity.
Is activated charcoal absorptive or adsorptive?
ADsorptive
How does SDAC work? (3)
- Toxicant must come in direct contact with AC.
- Toxicant-AC complex is not systemically absorbed; toxicant therefore removed with AC upon bowel movement.
- Allows for the adsorption of drugs and toxins through weak intermolecular forces
Can ethanol be adsorbed by SDAC?
No
Can digoxin be adsorbed by SDAC?
Yes
Can amitriptyline be adsorbed by SDAC?
Yes
Can acetaminophen be adsorbed by SDAC?
Yes
Can lithium be adsorbed by SDAC?
No
Can iron be adsorbed by SDAC?
No
Can cyanide be adsorbed by SDAC?
No
Can amphetamines be adsorbed by SDAC?
Yes
Can cimetidine be adsorbed by SDAC?
Yes
Can boric acid be adsorbed by SDAC?
No
Can petroleum distillates be adsorbed by SDAC?
No
Can methanol be adsorbed by SDAC?
No
Can codeine be adsorbed by SDAC?
Yes
Can chlordiazepoxide be adsorbed by SDAC?
Yes
Can salicylates be adsorbed by SDAC?
Yes
Can diazepam be adsorbed by SDAC?
Yes
Can ethylene glycol be adsorbed by SDAC?
No
Can malathion be adsorbed by SDAC?
No
Can chlorpromazine be adsorbed by SDAC?
Yes
When dosing SDAC - if the amount of toxicant ingested is know, we use __-__x the dose of the toxicant
10-40
Yay or nay? SDAC use more than 1 hour after toxicant ingestion?
No evidence to support or exclude the use of AC when more than 1 hour has passed since ingestion
We should start AC method within 1 hours of ingestion (if feasible), BUT we should consider these 4 things:
- Bezoar (clump of ingested pills)
- Modified release product
- Toxicant or co-ingestants that reduce GI motility/gastric emptying rate
- Effect of volume ingested on gastric emptying rate
When does SDAC see benefits well beyond 1 hour of toxicant ingestion? (3)
- Extended-release formulation
- Drugs that form bezoars
- Very large ingestions
What are 5 contraindications to using SDAC?
- Toxicant known not to adsorb to AC
- Unprotected airway (unconscious or trauma)
- Ingestion of hydrocarbons- risk of aspiration (destroy
surfactant, airway epithelium, alveolar septae, and pulmonary capillaries, leading to inflammation, atelectasis, and fever ) - Risk of GI perforation (has ulcer, surgery, took caustic
agent) - Endoscopy will be required (ex. corrosives)
Gastric lavage (pumping stomach) should not be considered unless…
Patient has ingested a potentially life-threatening amount of a poison and the procedure can be undertaken within 60 minutes of ingestion
What are some practical indications to gastric lavage? (6)
- Toxicant likely to be life-threatening
- Obvious signs and symptoms of life-threatening toxicity
- Reason to believe significant amount in stomach
- AC not an option (not adsorbed, dose required is unreasonable)
- No spontaenous emesis
- No highly effective antidote or alternative therapies pose high risk
What is whole bowel irrigation (WBI)?
Introduction of large amounts of fluid into the GIT to expel intraluminary contents
What is the rationale behind using WBI?
Cleanses bowel with large amounts of PEG (polyethylene glycol electrolyte) solution to minimize drug absorption and expel intraluminal contents out of the GIT; does not cause net change in ions, therefore no electrolyte imbalances.
WBI is an option for possibly doing what? (remember body packers)
Expediting the gastrointestinal luminal clearance of sustained-release preparations, toxic heavy metals, or packets of illicit drugs smuggled within the body (“body packers”).
What is used to perform WBI?
PEG-ES
What are the contraindications to doing WBI? (6)
- Unprotected or compromised airways
- GI compromise/GI hemorrhage
- Hemodynamically unstable
- Low BP: gut poorly perfused –> defective motility and cannot handle the high volume of PEG-ES in a coordinated manner –> abdominal distention and vomiting - Persistent vomiting
- Suspected leakage from drug packets or Bowel obstruction or perforation
- Expecting patients to drink adequate amounts of WBI fluid is unrealistic.
What are the complications associated with PEG-ES? (5)
- Nausea/vomiting
- Abdominal cramping / bloating
- Aspiration/ARDS (acute respiratory distress syndrome) –> because of misplacement of the NG tube
- Hypo-/hypernatremia (leading to altered consciousness, seizures, cerebral edema, and death)
- Interference with AC