Transcript Document
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: external exposure • 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 • 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 Toxicological Emergencies ACTIVATED CHARCOAL WITH OR WITHOUT A CATHARTIC Toxicologic Emergencies • 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/oz Baking 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 • Rodenticides 1. 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 Toxicological 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 Toxicologic Emergencies – Rodenticides 2. 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 Toxicological 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 Toxicologic Emergencies – Rodenticides 3. 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 • Clinical signs (starts within 1-2 h of ingestion) – – – – – – fatal) 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 23d Toxicological Emergencies Toxicologic 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 » » – Rx » » Large # nucleated RBC’s; basophilic stipling Blood lead conc >35 μg/ml 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 • Dx • Rx – Vomiting – CNS depression – Lethargy – Hx of exposure – Clinical signs – 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) – – – – – • Dx • Rx CNS depression, ataxia (may appear intoxicated) Vomiting PD/PU Seizures, coma, death Acute renal failure – Hx, signs – Ethylene Glycol Poison Test—an 8 min test used in cats and dogs – Calcium oxalate crystals – – – – 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 Toxicological Emergencies THE PROBLEM THE SOLUTION Toxicologic Emergencies • 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 – – – – – IV Fluid therapy Broad-spec antibiotics Intestinal protectants Muscle relaxers or Valium may be needed to control tremors Corticosteroids to counter endotoxic shock • Rx 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 – – – – – 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 • Rx Toxicologic Emergencies –Insecticides • Organophosphates and Carbamates • Signs • Rx – 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 – Salivation – Lacrimation – Urinary incontinence – Diarrhea – Dyspnea – Emesis, gastrointestinal cramping -May progress to – Seizures, coma, resp depression, death – – – – 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 • Rx – Hypersalivation, oral mucosal edema, local pruritis -Large amount of plant may cause: – Vomiting, dysphagia, dyspnea, abd pain, vocalization, hemorrhage – Rinse mouth with milk or water to remove Ca Oxalate crystals – GI decontamination (protectants) may be needed 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 Toxicologic Emergencies • 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)