Toxicology and Extracorporeal therapies (SACCM + Dobratz) Flashcards
For which toxicoses can ILE be considered as a life saving antidote?
- Macrocyclic lactones (ivermectin, moxidectin)
- Baclofen - muscle relaxants
- Ca channel blocker and B blockers
- Cholecalciferol
- Bromethalin
- NSAIDS (Ibuprofen, Naproxen)
- Marijuana
- Methamphetamine, cocaine
- Local anesthetics
- TCAs
List indications and contraindication to induce emesis
When is activated charcoal contraindicated
- Heavy metals (Fe, Zn), xylitol, alcohols (EG, ethanol, methanol) ? don’t reliably bind to AC
- Symptomatic patients who are at risk for aspiration pneumonia
- AC with a cathartic should be used cautiously in hypovolemic, in dehydrated patients or those with excessive free water loss (e.g., diabetes mellitus, renal disease, diabetes insipidus)
- Endoscopy
- GI obstruction, hemorrhage or perforation
- Recent surgery
- Ileus
- Ingestion of caustic substance or hydrocarbons
What are indication for multidose of AC?
- Enterohepatic circulation
- XR (extended release) / LA (long acting) / SR (sustained release)
Complications of activated charcoal
- Hypernatremia
- aspiration pneumonia
- the use of AC could confuse the diagnosis of intoxication of substances that can increase the osmolal gap such as ethylene glycol
- difficult endoscopy
- constipation
- corneal abrasion (if contact with eyes)
List catartics that can be used in VM
- sorbitol
- sodium sulfate
- magnesium sulfate
- magnesium citrate
List potential toxins that can cause CNS stimulation
- SSRIs, TCAs, amphetamines, 5-FU, Bromethalin, methylxantines, pyretrins, metaldehyde, strychnine, tremorgenic mycotoxins, sleep aids
List potential toxins that can cause CNS depression
Muscle relaxants (baclofen), opioids, sleep aids, marijuana, macrocyclic lactones (ivermectin, moxidectin)
T/F - α-agonist activity (such as imidazole decongestants found in nasal sprays and eyedrops or amitraz collars) can be reversed with the use of α-adrenergic antagonists such as yohimbine or atipamezole
TRUE
Explain mechanism of action of SAMe
- Acts as a methyl donor
- Generates sulfur-containing compounds that are imporant for conjugation reactions used in detoxfication.
- Acts as a precursor of glutathione
Explain mechanism of action of NAC for acetaminophen toxicosis
- Limits the formation of toxic metabolite NAPQI by providing alternative glutathione substrate with acetaminophen toxicosis (it is a glutathione precursor).
- Binds with APAP metabolites making them inactive
- Increases sulfate conjugation by being a sulfur donor.
Explain the lipid sink hypothesis of ILE therapy
compartimentalization of the drug in the lipid phase results in a decreased free drug concentration available to tissues
List effects of ILE other than “lipid sink”
- provides energy substrates to myocytes augmenting cardiac performance (remember FFAs are the preferred substrate for myocardial cells)
- restores myocardial function by increasing intracelular calcium
- Increasing the overall fatty acid pool, which overcomes inhibition of mitochondrial fatty acid metabolism (e.g., bupivacaine toxicosis).
What are the dosage recommendations of ILE in VM?
- Initial 20% ILE bolus 1.5 to 4 ml/kg (between 0.3 g/kg and 0.8 g/kg IV over 1 minute)
- followed by 0.25 ml/kg/min CRI (0.05 g/kg/min IV over 30 to 60 minutes)
- If not response: Intermittent bolusing at 1.5 ml/kg q4-6h for 24 hours can be considered; C19follow-up CRI doses of 0.5 ml/kg/hr (0.1 g/kg/ hr) can be continued until clinical signs improve (not to exceed 24 hours) or until serum is lipemic.
List adverse effects of ILE therapy
- fat embolism
- fat overload syndrom
- phlebitis
- local systemic infection if injection site is contaminated
- pancreatitis
- Interaction with lipophilic medications being given to patient
- worsening of ARDS (decreased PaO2:FiO2 ratio)
- allergic reactions, anaphylatic reactions
- interferance with lab tests
- Fat overload syndrome is reported in humans (not yet in VM) –> associated with excessive administration that overwhelms lipid clearance mechanisms and leads to: hyperlipidemia, hepatomegaly, splenomegaly, icterus, coagulopathy, hemolysis
Which components in regular therapies for toxicities can make a cageside Ethylene glycol test false positive?
- Propylene glycol in Diazepam
- Glycerol in activated charcoal
T/F - Chocolate increases the pyloric sphincter tone and can be recovered inducing emesis up to 8h after ingestion
TRUE
Emetis generally empty __% of gastric content
40% to 60%
T/F In general gastric lavage is more efficacious than emesis for decontamination
FALSE
In which circumstances is recommended to administer milk, water or liquid from water-packed tuna?
- SOME household products
- corrosive or irritant products
- exposure to toad secretions
- taste reactions due to topically aplied products (foaming kitties following flea spray application)
What is a side effect of administration of 3% hydrogen peroxide in cats?
25% of cats can develop severe hemorrhagic gastritis, rarely death
What is a consequence of inducing vomiting in a patient that ingested petroleum distillates or hydrocarbons (kerosene, gasoline, motor oil, transmision fluid)?
toxicants can easily be aspirated –> severe aspiration pneumonitis
What’s the mechanism of action of Apomorphine and in which species is not effective
- Acts on CRTZ (chemoreceptor trigger zone)
- cats
Xylazine causes emesis in ~___% of cats
50%