Decontamination

Question 1

Decontamination

Answer 1

• Goal is to eliminate any possible toxin and prevent its continued absorption
• Ocular, dermal or gastrointestinal

Question 2

Ocular decontamination

Answer 2

• eyes to be flushed for 20-30mins if exposed to toxic substance
• flush from medially to laterally
• prevent contamination of other eye
• short breaks in between to decrease stress levels
• alkaline agents = more destructive to tissues than acids
• causes liquefactive necrosis
• acids
• causes coagulative necrosis
• self-limiting

Question 3

Dermal decontamination

Answer 3

• rinsing or bathing
• mild dish soap
• lipophilic substances can be readily absorbed into dermis
• most water soluble substances are not

Question 4

Dilution

Answer 4

• Milk or water
• 2-6ml/kg
• sufficiently small amount to reduce likelihood of vomiting while diluting substances to reduce tissue damage

Question 5

Gastrointestinal decontamination

Answer 5

• gastric emptying and administer agents to hasten elimination of toxin
• ensure patient is alert to reduce risk of aspiration
• induce vomiting
  1. apomorphine
• synthetic opiate
• stimulates dopamine receptors in chemoreceptors zone
• IV (0.03mg/kg) IM (0.04mg/kg) or conjunctivally
• CNS depression
• can use naloxone to reverse CNS depression but won’t reverse emetic effects
  2. hydrogen peroxide
• 3% solution
• 1-2ml/kg
• gastric irritation
  3. xylazine (cats)
• alpha 2-adrenergic agonist
• 0.44-1.1mg/kg IM or SC
• sedation
• reversal: yohimbine(0.1mg/kg)
• only 40-60% of stomach contents vomited

Question 6

Activated charcoal

Answer 6

• absorbent
• large surface area
• effective absorption of many toxicants
• metals, ions and very small molecules are not well attracted to activated charcoal
• 1-3gm/kg
• can be used with a cathartic (sorbitol)
• increase GI motility and shorten absorption time
• should only be used once
• can be used multiple times to prevent enterohepatic recirculation
• when toxin is excreted via the bile into GI tract and reabsorbed

Question 7

Intralipid

Answer 7

• for fat-soluble toxins
• lidocaine
• bupivicane
• local anesthetic toxicity
• permethrins
• ivermectin
• baclofen
• some anti-depressant medications
• theorised
• lipid sink where fat soluble toxins can be bound and excreted without being metabolised
• 1.5ml/kg of a 20% solution - initial bolus
• then 0.26ml/kg/min for 1-2 hours
• filter
• can be repeated every few hours as needed
• before subsequent dosing, blood sample to assess lipemia
• if lipemia, do not repeat until serum is clear
• lipid infusion are excellent media growth
• need to be aseptically handed