Acute 4 (OD and poisoning) Flashcards
What are examples of anticholinergics?
- Tricyclic antidepressant (amitryptiline)
- All the “anti’s”
- Antihistamine
- Antipsychotic
- Antispasmodic
- Antimuscarinic (atropine)
What is the toxidrome of anticholinergic OD?
- HR increase
- RR normal
- Temp warm
- Pupils dilated
- Bowel sound absent
- Sweat dry
What is the presentation of anticholinergic OD?
- Toxidrome
- Urinary and bowel retention
- Dry mouth
- Hypereflexia and ataxia
What is the mental presentation of anticholinergic OD?
- Hypervigilant
- Agitated
- Hallucinating
What is the management of anticholinergic overdose?
- IV bicarb
- Amiodarone if VT (can’t give in TCA overdose, give lignocaine instead)
- Dialysis has no effect
What are examples of cholinergic agents?
- Sarin and tabun
- Pesticides (organophosphates)
- These are acetylcholinesterase inhibitors
What is the toxidrome for cholinergic OD?
- HR normal
- RR normal
- Temp normal
- Pupils pinpoint
- Bowel sounds present
- Sweaty
What is the presentation of cholinergic OD?
- Toxidrome
- Weakness, fasciculations and tremor
- Cardiac arrest
What is the management of cholinergic OD?
- Atropine
- Pralidoxime chloride
- Benzos
What is the toxidrome for opioid overdose?
- HR down
- RR down
- Temp down
- Pupils pinpoint
- Bowel sound absent
- Sweat dry
- (everything reduced)
What is the management of opioid overdose?
- Naloxone
- If pulmonary oedema then ventilate
What are examples of sympathomimetic drugs?
- MDMA agonists (amphetamines and ecstasy)
- Cocaine
Biochemistry of sympathomimetic drug OD?
- Increase in adrenaline, dopamine and 5HT
- Hyponatraemia
What is the toxidrome for sympathomimetic drug OD?
- HR increased
- RR increased
- Temp increased
- Pupils dilated
- Bowel sounds present
- Sweaty
- (effectively everything increased)
Presentation of sympathomimetic OD?
- Toxidrome
- Hyperreflexia
Mental change in sympathomimetic OD?
- Agitated
- Paranoid
- Euphoric hallucination
Management of sympathomimetic OD?
- BZD
- Ischemic chest pain -> GTN
- Hyperthermia -> dantrolene
-Hypertension -> sodium nitroprusside, B blocker 2nd line (can cause unreglualted alpha stimulation) - Acidosis -> bicarb
Cocaine specific risks?
- Stroke
- Aortic dissection
- QRSS widened and QT prolonged
Ecstasy specific risks?
- Can cause serotonin syndrome
- Hypoglycemia
- Metabolic acidosis
Examples of sedatives?
- Benzos
- Barbituates
- Alcohol
What is the toxidrome for sedative overdose?
- HR down
- RR down
- Temp down
- Pupils normal
- Bowel sounds absent
- Sweat dry
- (everything down except pupils)
What is the presentation of sedative OD?
- Toxidrome
- CNS depression
- Benzos: nystagmus and diplopia
- Alcohol: hypoglycaemia
Treatment of benzodiazepines overdose?
- Flumenazil (cures reso depression)
- Can’t give if had TCA or have epilepsy
- Causes seizure and cardiac arrest
-Only given in life threatening or iatrogenic OD and never out of hospital
Treatment of alcohol overdose?
- IV Glucose as causes hypo
- Never give glucose before pabrinex or u cause wernickes
- Chlordiazepoxide
Which patients are at risk from paracetamol poisoning?
- Those on CYP450 inducers (St John’s wort, carbamazepine, rifampicin, alcohol (chronic), phenytoin)
- Malnourished
Management of paracetamol poisioning?
- Activated charcoal (Od in last hour and not staggered)
- N-acetylcysteine (>1 hour, staggered OD, level >100 at 4 hours and 15 at 15 hours)
Aspirin OD?
- Mixed respiratory alkalosis and metabolic acidosis
- Tinitus and hyprventilation
- Causes hypoglycaemia which can lead to coma or seizure
- Treated with charcoal in 1 hour, IV bicarb, or dialysis if severe
Digoxin overdose?
- Main trigger is hypokalaemia
- Present with gynaecomastia and yellow-green visual loss
ECG changes of digoxin overdose?
- Downsloping ST (reverse tick sign)
- Flat or inverted T waves
- Short QT
- AV block and bradycardia
Features of lithium OD?
- Thirst and polyuria
- Coarse tremor (fine tremor seen normally)
- Severe: acute confusion and hypereflexia
Precipitating factors for lithium OD?
- Dehydration, AKI, renal failure
- Drugs that cause the above: ACEi, ARB, NSAIDs, thiazide, metronidazole
Features of beta blocker OD?
Exaggerated effects of beta blockers (bradycardia, heart block etc)
Features of iron OD?
- Hard to do (need a lot)
- Grey black vomit and melena
- GI symptoms
- Severe: liver necrosis and metabolic acidosis
Features of CO poisoning?
- Exposure to poor ventilation system
- Headache and nausea most common
- Severe: pink skin, hyperpyrexia, extrapyramidal symptoms
Features of cyanide poisoning?
- Initial resp symptoms and palpitations
- Bitter almond smelling breath
What are the 3 stages of ethylene glycol poisoning?
1) Drunk
2) Metabolic acidosis with high ion gap
3) AKI and convulsion
