Poisoning Flashcards
Skin Decontamination
Prevent grooming (self and others)
Clip the coat
Lots of warm water and gentle detergents
Do not bathe seizuring animals !
Ocular Decontamination
Irrigate the eye for at least 15 minutes
Water / saline
Fluoroscein assessment
Corticosteroids only if no ulceration
Viscotears / topical antibiotics
Methods of gut decontamination
apomorphine (dogs only) xylazine syrup of ipecac 3% hydrogen peroxide gastric lavage
Apomorphine
- use
- dosage
- side effects
- induction of emesis
- 0.44mg/kg IM or S/C
- Moderately effective
- Sedation and cardiorespiratory depression
Syrup of Ipecac
- uses
- pharmacological properties
- side effects
induction of emesis
Slow onset and less reliable
Gastric irritation and stimulation of CRTZ
Do not confuse with the more concentrated extract
Repeat doses can cause cardiotoxicity
Hydrogen Peroxide
- use
- dosage
- side effects
- warning
induction of emesis
1-2ml/kg P.O (max 10mls in cats and 50mls dogs)
Mild gastric irritation.
Repeat administration no more than once.
Activated charcoal
- how
- effectiveness
- directions
Binds toxin and stops further absorption
Variable effects on different toxins
Liquid and powder > tablets
Give in food or via stomach tube every 4 hours
Acetaminophen
- fatal doses
- cats prone
- when are clinical signs seen
500mg/kg probably fatal in dogs
200mg/kg fatal in cats
cats lack glucuronyl transferase enzymes which bind to it and make it inactive
clincial signs seen within 4 hours
Acetaminophen
- clinical signs (general)
- <12 hours (6)
- 2-7 days (6)
Hepatic necrosis
Methaemoglobin formation (chocolate blood)
Heinz body anaemia
Resulting haemolytic anaemia leads to tissue hypoxia
less than 12 hours:
- anaemia
- hypoxia
- cyanosis
- tachypnoea
- tachycardia
- facial/paw oedeam
2-7 days:
- haematuria
- anemia
- icterus
- liver failure
- seizures/coma
- renal failure
death normally after 2-7 days
Diagnosis of acetaminophen poisoning
History / clinical signs
Methaemoglobin
Heinz bodies
Liver and renal disease
Treatment for acetaminophen poisoning
-Required if >10mg/kg (cats) or >150mg/kg (dogs)
-Emetics if < 1-2 hour post ingestion
-Absorbents ?
-Supportive care – IVFT, oxygen, blood products
-N-acetylcysteine
promotes metabolism to non toxic form
- S-adenosylmethionine (S-AME)
- Ascorbic acid – converts methgb to haemoglobin
- Cimetidine in dogs
Metaldehyde
Molluscicide : pellets or solutions
Metaldehyde
- clinical signs onset
- clinical signs (4)
Onset of clinical signs seen from 30mins – 3 hours
Hyperaesthesia, tremors, seizures and hyperthermia
Decreases inhibitor neurotransmitters
Death due to respiratory arrest / seizures
If survives may have chronic neurological abnormalities
Treatment of metaldehyde
Treat regardless of dose ingested
Emetics if asymptomatic – OBSERVE
If seizures
Diazepam (propofol if non responsive)
+/- gastric lavage
IVFT and nursing care
Gradual recovery normally seen
Anti-coagulant Rodenticides
Inhibition of vitamin K activation
very prolonged duration of action is seen
Mechanism of action
Vit K changes Vit K1 epoxide (inactive) to Vit K hdroquinone (active).
Vit K hydroquinone changes coagualation factor precursors into activate cogaculation factor precursors.
CS of metaldehyde poisoning
Delayed absorption (12-24 hours)
2-5 days until coagulopathy develops
Lethargy and dyspnoea
Epistaxis / haemoabdomen
Diagnosis of Metaldehyde poisoning
Prolonged Prothrombin Time (PT) – most sensitive (extrinsic pathway)
Vitamin K dependent factor with shortest half life – Factor VII
Prolonged APTT
Platelets – normal or decreased
PIVKA – proteins induced by vitamin K antagonism
Treatment of metaldehyde poisoning
Immediate support
Oxygen
Transfusion (clotting factors and red cells)
Prevent further absorption
Emetics if recent ingestion (<4h)
Adsorbents (charcoal)
Vitamin K1
Loading dose of 5mg/kg/sc
Clotting factors improve within 6 hours
Then 2.5-5mg/kg PO or S/C every 24 hours
Continue for up to 4 weeks
Caution when stopping (check PT 48 h after stopping)
Ethylene glycol
Anti-freeze intoxication
Fatality seen if volume ingested > 6.6mg/kg
Disease progression of ethylene glycol poisoning
< 12 hours
Neurological signs (ataxia, twitching, seizures)
Renal disease
Acidosis
12-24 hours
Cardiac / respiratory system affected
24-72 hours
Renal – azotaemia, anuria and hyperkalaemia
Diagnosis of ethylene glycol poisoning
Acidosis (serum pH < 7.3)
Azotaemia
Hypocalcaemia
Calcium oxalate crystals in urine
Treatment of ethylene glycol poisoning
Emetics?
Absorbents not useful
Diazepam for seizures
Correct acidosis
IVFT - monitor urine output and electrolytes
Ethanol
Best used within 12 hours
Can be given IV or via stomach tube
4-Methylpyrazole (dogs only)
Inhibits activity of alcohol dehydrogenase
Less side effects
Theobromide
Toxic dose in dogs = 100-150mg/kg
White chocolate – 0.25mg/ oz
Milk chocolate – 44mg/oz (treatment needed if > 9g/kg)
Baking chocolate – 400 mg / oz (treatment needed if > 1g/kg)
CS of theobromide poisoning
Direct stimulation of CNS and cardiac muscles Seizures Arrhythmias Muscle tremors Hyperactivity Ataxia Death
Pancreatitis
Gastroenteritis
Theobromide treatment
Gastric evacuation – Apomorphine
IV fluid diuresis
ECG – Ventricular tachycardia Lidocaine
Supraventricular tachycardia Propanolol
Seizure watch – Diazpeam / Midazolam
Gastroprotectants – Omeprazole
Xylitol
- what
- toxic doses
sugar substitute
Toxic dose
Hypoglycaemia – 0.15g/kg (30mins)
Hepatic necrosis – 1.4g/kg (<3 days)
Gum contains 0.3 – 1g/ piece
Treatment of xylitol
Decontamination – charcoal of questionable use
Monitoring – glucose / ALT / clotting times
Supportive care – Fluids / dextrose
Liver protectants – N-acetylcysteine, S-AME
