toxicologic emergencies

TOXICOLOGIC EMERGENCIES

• Signs will vary depending on character of toxic compound• Toxicity can result from exposure via many routes

• Ingestion• Inhalation• Skin contact• Injection

Toxicologic Emergencies

• Top 10 Toxicoses (2005)– Human medication (ibuprofen, acetominophen, anti-depressants)– Insecticides—flea and tick– Rodenticides—anticoagulants– Veterinary medication– Household cleaners—bleach, detergents– Plants—sago palm, lily, azalea– Herbicides– Chocolate—highest in food category– Home improvement products—solvents, adhesives, paint, wood glue– Fertilizers

Toxicologic Emergencies

• HISTORY• ASSESS• STABILIZE

– Administer oxygen– Control seizures– Correct cardiovascular abnormalities

• DECONTAMINATION– Emetics– Activated charcoal– Gastointestinal protectants

• CONTROL CLINICAL SIGNS• GOOD NURSING CARE• PREVENT FURTHER EXPOSURE

Toxicologic Emergencies

• Ocular exposure• Rinse eyes with copious saline for 20-30 min• Chemical burns treated with lubricating ointment and suture lids

closed• Use corticosteroids only if corneal epithelium is

intact• Skin exposure

• Bathe with mild detergent (liquid dish soap)• Bather should wear protective clothing (gloves, goggles)

Toxicologic Emergencies: external exposure

• Ingestion • Induce vomiting—if chemical not caustic; animal conscious, not seizing

• Syrup of ipecac, apomorphine, Xylazine, H2O2 (not reliable), salt (not recommmended)• Dilute caustic substances with milk, water• Gastric lavage—large bore stomach tube; light anesthesia w/ endotracheal tube• Administer absorbents—activated charcoal inhibits GI absorption

• Give orally or via stom tube• Enemas/cathartics to eliminate toxins more rapidly

Toxicologic Emergencies

Toxicological Emergencies

ACTIVATED CHARCOAL WITH OR WITHOUT A CATHARTIC

• Methylxanthines (caffeine, theobromine, theophylline

• Found in: coffee, tea, chocolate, other stimulants• Toxic Dose of caffeine and theobromine in dogs:

100-200 mg/kg; (other sources: 250-500mg)• Milk Chocolate—44-60 mg/oz

Dark chocolate-150 mg/ozBaking Chocolate—390-450 mg/oz

Toxicologic Emergencies

• Clinical signs of methylxanthine/chocolate toxicosis (caffeine, theobromine)

– Increased HR, RR– Anxiety– Vomiting/diarrhea– Seizures, coma– Cardiac arrhythmias

• Treatment– Induce vomiting– Activated charcoal– Control seizues– Fluid therapy

Toxicologic Emergencies

• Rodenticides1. Anticoagulants

(warfarin, pindone, bromadiolone, brodifacoum)

• Work by binding Vit K, which inhibits synthesis of factors II, VI, IX, X

• This effect occurs within 6-40 h in a dog; effect may last 1-4 wk

Toxicologic Emergencies

• Clinical signs (occur after depletion of clotting factors)– Lethargy– Vom/dia with blood; melena– Anorexia– Ataxia– Dyspnea – Epistaxis, scleral hemorrhage, pale mm

• Treatment– Vit K: 3-5 mg/kg PO for up to 21 d depending on anticoagulant used– Induce vomiting; activated charcoal– Whole blood transfusion if anemic

Toxicological Emergencies

– Rodenticides2. Cholecalciferol—Vit D3; used in Quintox, rampage, Rat-Be-Gone

-causes Ca++ reabsorption from bone, intestine, kidneys causing hypercalcemia (>11.5 mg/dl) and cardiotoxicity

• Clinical signs (12-36 h after ingestion)– Kidney failure

» Anorexia» Vomiting» Tissue mineralization

– Cardiovascular abnormalities» Muscle weakness» arrhythmias

Toxicologic Emergencies

• Diagnosis– Hx of exposure– Usually discovered on routine Chem panel (↑blood Ca++)

• Treatment– Induce vom/activated charcoal if ingestion occurred with 2 h– Furosemide x 2-4 wk; increases Ca++ excretion in urine– Prednisone x 2-4 wk; decreases Ca++ reabsorption from bones/intesine– Calcitonin to lower blood Ca++ concentration

Toxicological Emergencies

– Rodenticides3. Bromethalin

-uncoupler of oxidative phosphorylation in CNS (stops production of ATP)-Causes cerebral edema-found in Assault, Vengence, Trounce-Toxic Dose Dog: 4.7 mg/kg

Cats: 1.8 mg/kg

Clinical signs (>24 h after ingestion of high dose; 1-5 d--low dose)– Excitement, tremors, seizures– Depression, ataxia

• Rx (will take 2-3 wk to know if animal will survive)– Purge GI tract if exposure recent– Reduce cerebral edema with Mannitol and glucocorticoids– Seizure control with Diazepam and Phenobarbital

Toxicologic Emergencies

• Acetaminophen• Common OTC drug for analgesia• Toxic dose: Dog—160-600 mg/kg

Cat—50-60 mg/kg (2 doses in 24 h is almost always fatal)• Clinical signs (starts within 1-2 h of ingestion)

– Vomiting, salivation– Facial and paw edema– Depression– Dyspnea– Pale mm– Cyanosis due to methemoglobinemia

• Px—poor• Rx

– Induce vom/activated charcoal– Antidote: N-Acetylcysteine (loading dose of140-280 mg/kg PO, IV, then at 70 mg/kg PO, IV QID x

2-3 d

Toxicologic Emergencies

Toxicological Emergencies

– Metals• Lead toxicity more common in dogs than cats

– Source» Lead paint (prior to 1970’s) is primary source» Batteries, linoleum, plumbing supplies, ceramic containers, lead pipes, fishing sinkers,

shotgun pellets– Clinical signs (Usually involves signs of GI and nervous systems)

» Anorexia» Vom/dir» Abd pain-CNS signs do not show initially» Blindness, seizures, ataxia, tremors, unusual behavior

Toxicologic Emergencies

–Metals• Lead toxicity

– Dx» Large # nucleated RBC’s; basophilic stipling » Blood lead conc >35 μg/ml

– Rx» Remove lead from GI tract (cathartic, Sx)» Chelators (to bind the Pb in blood stream and hasten its removal)

-Calcium EDTA (ethylene diamine tetra acetic acid)-Penicillamine

» IV fluids for dehydration and to speed removal via kidneys» Diazepam, Phenobarbital to control seizures

Toxicologic Emergencies

– Metals• Zinc Toxicosis

– Usually from ingested pennies, galvanized metal, zinc oxide ointment

• Clinical signs– Vomiting– CNS depression– Lethargy

• Dx– Hx of exposure– Clinical signs

• Rx– Remove metal objects endoscopically or

surgically– IV fluid therapy– Ca EDTA chelation

Toxicologic Emergencies

• Ethylene Glycol (antifreeze; sweet taste)• Lethal dose: Cat—1.5 ml/kg

Dog—6.6 ml/kg• Signs (onset within 12 h of ingestion)

– CNS depression, ataxia (may appear intoxicated)– Vomiting– PD/PU– Seizures, coma, death– Acute renal failure

• Dx– Hx, signs– Ethylene Glycol Poison Test—an 8 min test used in cats and dogs– Calcium oxalate crystals

• Rx– Emesis, adsorbents if ingestion within 3 h of presentation– IV fluids, NaBicarb for acidosis– Ethanol inhibits ethylene glycol metabolism Dogs (Cats): 20% ethanol—5.5 (5.0) ml/kg q6h x 5, then q8h x 4 – 4-methylpyrazole has been shown to be effective

Toxicologic Emergencies

Toxicological Emergencies

THE PROBLEMTHE SOLUTION

• Snail Bait (Metaldehyde, methiocarb)– Metaldehyde mechanism unknown– Methiocarb is a carbamate and parasympathomimetic

• Signs– Hypersalivation– Incoordination– Muscle fasciculations– Hyperesthesia– Tachycardia– Seizures

• Rx– Emesis and absorbents– Pentobarbital, muscle relaxants to control CNS hyperactivity

Toxicologic Emergencies

• Garbage Toxicity– Common in dogs; not in cats– Enterotoxin-producing bacteria include

Strep, Salmonella, Bacillus• Signs (within min to h after ingestion)

– Anorexia, lethargy– Vom/dia– Ataxia, tremors– Enterotoxic shock can cause death

• Rx– IV Fluid therapy– Broad-spec antibiotics– Intestinal protectants– Muscle relaxers or Valium may be needed to control tremors– Corticosteroids to counter endotoxic shock

Toxicologic Emergencies

• Insecticides• Pyrethrins, Pyrethroids, Permethrins

– Common ingredients of flea/tick sprays, dips, shampoos, etc– If used according to instructions, toxicity rarely occurs; if overused, toxicity can result

• Signs– Hypersalivation– Vom/dia– Tremors, hyperexcitability or lethargy– Later, dyspnea, tremors, seizures can occur

• Rx– Bathe animal to remove excess– Induce vomiting/charcoal/cathartics for ingestion– Diazepam may be necessary for mild tremors– Methocarbamol, a muscle relaxer, for moderate-severe tremors– Atropine for hypersalivation and bradycardia

Toxicologic Emergencies

– Insecticides• Organophosphates and Carbamates

– Inhibit cholinesterase activity (break down of Ach is inhibited)– Highly fat-soluble; easily absorbed from skin and GI tract– Found in dips, sprays, dusts, etc for fleas and ticks, and flys

• Signs– Salivation– Lacrimation– Urinary incontinence– Diarrhea– Dyspnea– Emesis, gastrointestinal cramping-May progress to – Seizures, coma, resp depression, death

• Rx– Bathe animal– Charcoal if ingested– Atropine (0.2-0.4 mg/kg; half IV, half IM or SQ)– Praloxime chloride (20 mg/kg BID till signs subside)—reactivates cholinesterase

Toxicologic Emergencies

• Plant Toxicity– Most common in confined and juvenile animals– Usually from ornamental, indoor plants– Severity varies with plants– ID scientific plant name (florist, greenhouse)

• Araceae family (most from this family) – Dumb cane, split-leaf philodendron– Contain calcium oxalate crystals

• Signs– Hypersalivation, oral mucosal edema, local pruritis-Large amount of plant may cause:– Vomiting, dysphagia, dyspnea, abd pain, vocalization, hemorrhage

• Rx– Rinse mouth with milk or water to remove Ca Oxalate crystals– GI decontamination (protectants) may be needed

Toxicologic Emergencies

Dumb Cane (Dieffenbachia)• aka Mother-in-law’s tongue• Oral irritation; intense burning,

excess salivation

Split Leaf Philodendron• Oxalate crystals like Dieffenbachia• Oral irritation; intense burning, excess salivation

Lily of the Valley• Contains cardiac glycosides• Cardiac arrythmias, death

Azalea (Rhododendron) • Hypotension, cardiovascular collapse, death

Sago Palm

• ALL PARTS OF THE PLANT ARE TOXIC• Coagulopathy• Liver failure

• Phone advice to give owners (legal issues)• Protect yourself from exposure before handling animal

• Gloves, protective clothing• Protect yourself from animal because poisoned animals may act strangely• Protect animal from further exposure by removing pet from source• Bring sample of vomit, feces, urine• Bring container/package that toxin was in and a sample of the toxin (plant

material, rat bait, etc)

Toxicologic Emergencies