Toxicology Flashcards
What would generally be considered a minimum database?
PCV/ TS BG BP Lytes Urea/ Crea ECG Lactate
How can you decontaminate the skin?
e.g. pyrethrins/ organophosphates
luke warm water, soapy detergent, wear gloves
If in petrol/ diesel - then use vegetable or mineral oil first
How long after ingestion of a substance can you induce emesis?
Normally up to 4 hours
EG - only an hour
Chocolate and neurotoxins can sit in the stomach - up to 8 hours
What are the contraindications for inducing v+?
Neuro signs
Already v+
Caustic
Bread dough
How can you do gastric lavage?
GA - so can do on neuro patient Ensure enflated ET tube Lubricated stomach tube Do in cycles of 30-40ml/kg Keep doing it until the fluid runs clear Remove the tube partially inflated kink the stomach tube to prevent leakage when removing Wash out the mouth
What is the use of charcoal?
Adsorbs to toxins to prevent absorption
Normally 1-2 doses, but do repeated dosages if there is enterohepatic circulation (e.g. NSAIDs/ ivermectins)
DO NOT GIVE WITH FOOD
What is theobromide?
A type of methylxanthine (like caffiene and theophylline)
Causes CNS stimulation
and cardiac and skeletal muscle stimulation by inhibiting Ca recycling
Both dogs and cats affected
What are the clinical signs of theobromide toxicity?
Hyperactivity/ hyperreflexia U+ incontinence from diuresis V+/D+ Muscle twitching/ seizures tachycardia/ tachy arrhythmia
How can you manage a theobromide toxicity?
Decontaminate and activated charcoal if able Anti epileptic drugs Anti arrhythmics (B blockers/ Ca channel blockers) - only give these if volume resuscitated first
How can grapes cause toxicity?
Mechanism unknown
Any grape product - juice/ raisins/ wine etc
What does lily toxicity cause?
Mechanism unknown but causes renal tubular death
How do you manage lily or grape toxicity?
If recent - decontaminate, activated charcoal, IV fluids for 24 hours, baseline urea creatinine and lytes
Monitor - weight, u+ output, bloods @ 24 hours
What would be the signs of a lily or grape toxicity developing?
Increase in weight/ decrease in urinary output
Increased urea/ crea
Granular casts in u+ microscopy
How should you treat a lily or grape toxicity that has clinical signs on presentation?
Fluids - balance lyte solution (CSL good to balance acid/ base)
Maintain BP and renal perfusion
Prevent further 2ndary injury
Correct pre existing lyte imbalance (e.g. low Cl from v+, low Ca from acidosis)
Encourage diuresis (fluids/ frusemide)
What is the use of frusemide for inducing diuresis?
Na/K/Cl2 pump inhibitor Acts on ascending loop of henle 4mg/kg IV bolus Followed by 2mg/kg every 4-6 hours Little proven efficacy in anuric/ oliguric patients
What is the only real effective treatment for anuria/ oliguria?
Dialysis
not a specific treatment but buys the kidney time to recover
How often should you monitor bloods on AKI patients
Normally every 6-12 hours for lytes
24 hours urea and crea - expect these to get worse for at least the first 2 days, then plateau
numbers are not related to prognosis
Lower UO is what is related to prognosis
N.B takes 6 weeks to know prognosis, unlikely to get CKD
What is toxic with ethylene glycol?
Metabolites - the worst are glyco-aldehyde and glycolic acid
What are the stages of ethylene glycol toxicity?
One - 2-12 hours after
sweeth breath, drunk, V+
Two - 6-24 hours
Show neuro signs
Three - 24-48 hours after
AKI
What can help dx ethylene glycol toxicity
Clinical signs
Severe acute azotaemia
There are test kits available
Ca oxalate monohydrate crystals in large numbers
On U/S - kidney halo - bilateral hyperechoic corticomedullary junction
High Anion gap
How do you treat EG toxicity when no clinical signs are yet noted
Emesis within an hour - one of the few indicatons of at home emesis
Prevent EG metabolism - competitively inhibit alcohol dehydrogenase enzyme
Ethanol given IV then a CRI - give for 12 hours if a test is -ve
48 hours if no signs of azotaemia
Best treatment would still be dialysis as it removes it from the body
How does metaldehyde cause issues
Metabolised to acetylaldehyde
Decreases GABA, nor adrenaline and 5 HT activity
Therefore lack of CNS inhibition
What are the signs of metaldehyde toxicity?
Restlessness, anxiety, p+
Ataxia, ptyalism, muscle fasciculations
Seizures, hyperthermia, coma, death
How can you Dx metaldehyde toxicity?
Acute onset progressive seizures
Possible exposure
green v+/ f+
Rule out other causes (low Ca or BG)