4a – Management of Poisoned Animal Flashcards
When do you consider poisoning?
- Sudden onset of illness or sudden death in otherwise healthy group
- Illness following change in food, medications or environment
- Animal left in environment for extended period of time with potential access
- Vague, non-specific illness that hasn’t responded to other treatments
- Concerns for intentional poisoning
- If blood work findings are unexpected
What is the approach to a poisoned animal?
- Stabilize patient
- History/research of toxin, PE
- Decontamination
- Give antidote (if available)
- Minimum database
- Symptomatic and supportive therapy, including monitoring
Evaluate the patient
- Immediate poisoning: highest priority
- Triage
o Examine life-threatening problems
o A: airway
o B: breathing
o C: circulation
o D: disability
o E: external assessment
o TPR
o Neurologic assessment: level of consciousness
What are the 3 key things for taking a toxicology history?
- What?
- How much?
- When?
- *ID and treat immediate life-threatening problems, do NOT wait for confirmation of poisoning
- *always treat the patient NOT the poison
Taking a toxicology history: what?
- Name of product, name of drug, % or dose
- All ingredients
Taking a toxicology history: how much?
- Estimate ingested amount
- Compare to LD50 or minimum lethal dose
Taking a toxicology history: when?
- Has the animal developed any symptoms at home?
- Does this change your treatment?
Taking a toxicology: other important info
- Current meds
- Other animals involved
- Significant health history
- If there have been other treatments
What are the principles of decontamination?
- Minimize absorption and/or promote elimination
- Remove or dilute a topic irritant or corrosive
- When benefits of decontamination outweigh risks
o Not necessary for all exposures - *will depend on the route of exposure
Majority of toxins are ingested: GI decontamination
- Inducing emesis
- Administration of activated charcoal
- Gastric lavage
Emesis
- Action or process of vomiting: stomach and proximal duodenum emptied
- *stimulation of CTZ in medulla or peripheral (GI) receptors
- *first line treatment for GI decontamination
- Give a small meal before inducing emesis if animal has an empty stomach
What are the indications for emesis?
- *Recent ingestion: ideally 1-2hr
- Effective for small, uncharged molecules and weak acids
- *Asymptomatic patient: not absorbed yet (hasn’t had time to act)
- Unknown ingestion
Vomiting
- Active
- Retching
- Prodromal signs
- Stomach and proximal duodenum emptied bile
Regurgitation
- Passive
- No retching
- No prodromal signs
- Esophagus emptied
- Undigested food and mucus
- No bile
What are some drugs to induce emesis?
- Apomorphine: dogs
- Xylazine: cats (NAVLE)
- Dexmedetomidine or hydromorphone (cats)
Efficacy of emesis in dogs
- Apomorphine: 94%
o Goes quicker - 3% hydrogen peroxide: 90%
Efficacy of emesis in cats
- Dexmedetomidine: 81%
- Xylazine: 44%
- NONE with hydrogen peroxide
What are the contraindications for emesis?
- SYMPTOMATIC PATIENTS
- Neurological animal
- Lack of pharyngeal reflexes
- Hypoxia, weakness
- Agent type: corrosive, sharp, rapid onset
- Animal already vomited or actively vomiting
- Brachycephalic dogs at home
- Animals that cannot vomit (rabbits, rodents, birds, horses)
When would you do emesis, but proceed with CAUTION?
- Brachycephalic breeds
- History of seizures
- Very young or old
- Recent GI surgery
- Significant underlying disease
What are the risks with emesis?
- *Aspiration
- Lack of efficacy
- Sedation
- Intussusception
- *consider hydration status AND ensure animal cannot consume its vomit
- *ADMINISTER ANTI-EMETIC
Anti-emetic drug examples
- Maropitant (Cerenia)
- Ondansetron (Zofran)
- +/- Metoclopramide
At home-emesis: hydrogen peroxide (3%)
- DOGS ONLY
- Stimulates pharyngeal receptors + local irritation
- Under recommendation
- Fresh/unexpired: bubbly
- Dose: 1-2ml/kg (max 3 tablespoons
- Potential side effects
o GI irritation and ulceration
o Aspiration
o Lack of efficacy
o GDV
What do you NOT use for at-home emesis?
- Salt
- Mustard powder
- Syrup of Ipecac
- Liquid dishwasher
- Your finger
- *do NOT spin the animal
Ropinirole: a new emetic
- Full DA-receptor agonist
- Approve in US in 2020
- Ophthalmic solution
- Side effects: protracted vomiting, ocular signs
- Effective, but not superior to apomorphine
Activated charcoal
- High heat and temperature processed wood=very porous
- *adsorption of compounds in the GIT to DECREASE ABSORPTION
- *first line treatment for poisoning
Indications for activated charcoal?
- Recent ingestion
- Asymptomatic, stable patient
What are the contraindications for activated charcoal?
- Alcohols, hydrocarbons, metals, nitrates/nitrites, salt, chlorates
- Severe dehydration
- Potential GI surgery
When do you give activated charcoal? What do you give with the first dose?
- Give immediately after pet has vomited
- First dose should contain cathartic (sorbitol)
What are some risk when administrating activated charcoal?
- Hypernatremia
- Poor visibility during endoscopy
- Aspiration
What are the risk factors for hypernatremia with activated charcoal?
- Dehydration
- Vomiting, fasting, or incapable of drinking water
- Predisposition to electrolyte imbalances
- Poisons that cause it (ex. chocolate, bromethalin, salt, playdough)
What are cathartics? What do they do?
- *Reduce GI transit time=enhanced fecal expulsion
- Ingredient in ToxiBan (read label of the product you are using)
What are the contraindications of cathartics?
- GI stasis
- Ingestion of caustic substance
- Patient is hypotensive and/or volume depleted
- Patient has diarrhea or has been given a laxative
- Renal insufficiency, electrolyte imbalance
Gastric lavage
- Flush stomach with water through an OG/NG tube to remove stomach contents
- Performed under (sedation or) GA with endotracheal intubation
- *wont do a ruminant
What are the indications of gastric lavage?
- Animal cannot vomit
- Emesis has been unsuccessful
- Large volume of stomach contents present (ex. bread dough, chocolate)
- Symptomatic patient
- Potentially lethal exposure
What are the contraindications of gastric lavage?
- Hydrocarbons or corrosives
- Liquid toxicants
- Patient is unstable
- Patient has high risk of bleeding/injury
- Recent surgery
- Too long post-ingestion (Ex. NOT in stomach anymore)
What are some of the considerations with gastric lavage?
- More effective then emesis alone
- *labor intensive: requires a team
- Volume
o Cold water=things move slower - PPE
- Need large enough tube for contents to be evacuated
- Kink the tube before removal
What are some other methods of decontamination?
- Dilution (Ex. milk for corrosive substances)
- Endoscopy: ex. batteries, coins
- Whole bowl irrigation
- Surgical removal: exploratory laparotomy
- Enemas
