Toxicology Flashcards
What are the 3 primary causes of poisoning?
- Intentional - [deliberate self poisoning, malicious/3rd party]
- Accidental [occupational, domestic, error/misunderstanding, prescribed medications]
- Recreational
How are poison’s introduced into the body/4 entry routes?
- Ingested
- Inhaled
- Injected
- Absorbed
What is the primary approach to the poisoned patient?
Priority is to circulation, airway, breathing. Adults CAB, paeds ABC
What are possible concerns regarding a poisoned patient?
- Pt contamination, and toxic environment.
- Aggressive/agitated Pt
- Dysrhythmias
- Loss of airway reflexes/burns to airway
- Seizures
- Hypoglycaemia
- Hyperthermia
- Consider resuscitation antidotes and other management.
Why would you require CCP back up for a poisoned patient?
- Pacing
- Dysrhythmia management
- Inotropic/chronotropic support
- Atropine in organophosphate poisoning
- Sodium bicarbonate in tricyclic overdose
- Calcium in CCB overdose
- Glucagon in beta blocker OD
- Management and/or sedation of agitated Pt’s
What is the risk assessment for the poisoned patient?
- Hx
- Agent(s)
- Dose(s)
- Time since ingestion
- Clinical features and progress
- Patient factors (weight & co-morbidities)
What did you take? When did you take it? What did you take with it? Have you vomited?
What is the role of poison’s information centre?
It’s a handy source of information and guidance. On call toxicologists available in specific cases.
What is a toxidrome?
Is a group of examination findings [S&S & Hx], it may suggest the pharmacology behind a person’s clinical presentation.
What are common toxidrome’s?
- Cholinergic
- Anticholinergic
- Sympathomimetic
- Opioid
- Serotonin
Go through the muscarinic effect acronym SLUDGEM-BBB
S = salivation L = lacrimation U = urination D = defecation G = GI upset E = emesis M = miosis
B = bradycardia B = bronchorrhea B = bronchospasm
Go through the muscarinic effect acronym DUMBELS
D = diarrhoea & Diaphoresis U = urination M = miosis [pinpoint pupils] B = bronchorrhea, Bradycardia & Bronchospasm E = emesis L = Lacrimation S = salivation
What are the 4 primary causative agents of cholinergic toxidrome - muscarinic effecs
- Organophosphates & carbamate insecticides
- Chemical warfare nerve agents
- Agents used in alzheimers dementia [donepezil, galantamine, rivastigmine, tacrine]
- Agents used in myasthenia gravis [neostigmine, physostigmine, pyridostigmine, endrophonium]
What is the nicotinic effects? [Cholinergic toxidrome] - (MATCH)
M = muscle weakness/fasciculation A = adrenal medulla activity T = tachycardia C = cramping H = hypertension
What are some signs & symptoms of anticholinergic toxidrome? [Catch phrase]
“Red as a beet, dry as a bone, blind as a bat, mad as a hatter and hot as a hare”
- Dry skin
- Hyperthermia
- Thirst
- Dry mouth
- Dilated pupils
- Tachycardia
- Urinary retention
- Slowed gastric emptying
- Decreased bowel sounds
- Delirium
- Hallucinations
What are (up to) 10 examples of causative agents for anticholinergic toxidrome? [drugs/agents]
- Antiparkinsonian drugs [benxtropine, amantadine]
- Antitussives [dextromethorphan]
- Antihistamines [promethazine, doxylamine]
- Motion sickness agents [mecilizine, hyoscine-scopolamine]
- Bronchodilators [ipratropium]
- Antimuscarinic agents [atropine, hyoscyamine]
- Antidepressants [Tricyclic]
- Anticonvulsants
- Atypical antipsychotic agents
- Antipsychotic agents
What are the examples of sympathomimetic toxidrome?
- CNS excitation
- Seizures
- Tremor
- Hyperreflexia
- Hyper/hypotension
- Tachycardia
- Low potassium, raised blood glucose, acidosis
What are some causative agents for sympathomimetic toxidrome?
- Amphetamines
- Cocaine
- LSD
- Caffeine
- Theophylline [related to caffeine]
- Phencyclidine [amphetamine derivative]
- Methylphenidate [ritalin]
What is serotonin toxidrome [syndrome] ? (Factors related to it)
- Mental status [agitation/restlessness/ confusion/hypomania]
- Fever
- Motor system [clonus/myoclonus, tremor/shivering, hyperreflexia/rigidity]
- Autonomic nervous system [diaphoresis/tachycardia/flushing]
What are some causative agents for serotonin syndrome?
- Selective serotonin re-uptake
- SNRIs
- Antidepressants
- Monoamine oxidase inhibitors
- Lithium
- Antiemetics
- Analgesic agents and antitussives
- Anticonvulsants
- Drugs of abuse
- Ginseng
- St Johns Wort
How would you manage serotonin syndrome?
Manage ABC’s, hyperthermia, dehydration, hyperreflexia/rigidity (CCP’s)
What are some conditions that result from opioid toxidrome?
- CNS depression
- Hypoventilation
- Hypotension
- Miosis
- Rapid response to naloxone
What are 3 other opioids/medications that have special cases for risk assessment?
- Destropropoxyphene
- Tramadol
- Pethidine
What are some clinical features of opioids?
- Opioid toxidrome [CNS depression, hypoventilation, hypotension]
- Tachycardia
- Bradycardia
- Pulmonary oedema
- N & V
- Prolonged non-lethal intoxication can lead to hypothermia, compartment syndrome, skin necrosis, hypoxic brain injury.