Lecture 2 - General Management Principles & Toxidromes Flashcards
May not be easy to determine whether it’s an _____, allergic, or idiosyncratic rxn
overdose
If a patient is ______ you must question whether it is a true overdose or trauma
unconscious
Should the condition of the patient or the specific agent determine the management strategy?
Clinical condition
“Treat the patient, not the poison”
What is used to assess the degree of consciousness?
Glascow Coma Scale
Describe the basic algorithm for emergency management
- Supportive care
- Airway management
- Circulatory support
- Obtain history
- Physical examination
- Determine if toxidrome present
- Laboratory Evaluation
- Management strategies
Define toxidrome
A group of signs and symptoms constituting the basis for a diagnosis of poisoning
____ ______ provides airway control
endotracheal intubation
How does endotracheal intubation provide airway control?
- Minimizes aspiration of gastric contents
- Ability to remove secretions
- Access to lungs to allow optimization of oxygenation and ventilation
What can hypotension occur due to?
- Depression of myocardial contractility
- Depress CNS cardiorespiratory centres (ex. clonidine)
- GI fluid losses
- Peripheral vasodilation
Rule out other causes of hypotension such as due to _____ or ____ _____
trauma or blood loss
How do you manage hypotension?
- Volume expansion (ex. 0.9% NaCl, blood products)
- Vasopressors (ex. dopamine or norepinephrine)
What other manifestations do you need to consider?
- Seizures
- Arrhythmias
- Electrolyte disturbances
- Hypoglycemia
What are some things you need to try to obtain as part of patient history?
- age
- amount ingested - empty vials: own meds vs someone else’s meds
- medication history - family, friend, pharmacy
- time ingested
- time course of symptoms
- identification of meds or toxin (ex. pill left in vial, empty vials)
- symptoms
- circumstances of poisoning (accidental vs suicide)
- pre-hospital interventions
- associated conditions/past medical history
Why is a repeated assessment of physical examination required?
-because patient status can change over time
and
-the time relationship of symptom presentation can be helpful in determining the toxin
What is part of physical exam?
- Vital signs
- Temperature alterations
- Skin (ex. needle tracks, flushing, muscle tone)
- Breath (smell can help with identification - ex. alcohol)
- Lungs - ex. aspiration, wheezing
- Heart -arrhythmia
- Abdomen - ex. ileus/bowel sounds
- Neurological - ex. level of consciousness, response to voice/pain, presence of seizure, pupils
Toxidrome
A group of signs and symptoms associated with a particular agent or toxin; also known as “symptom complexes”
When are toxidromes most helpful?
when reviewing the clinical presentation and formulating the framework for assessment
What limits the applicability of lab results?
time constrains
What are some indications for laboratory testing?
- Monitoring
- Diagnostic confirmation
- Screening
What is a Tox-Screen?
A combination of analytical procedures to help identify multiple common drugs encountered in an overdose
What methods can be used for a tox-screen?
- immunoassays, thin-layer chromatography, gas chromatography
- can have long turn-around time
- immunoassays relatively fast
Tox screen uses what fluids?
blood, urine, other
Tox screen has a major problem of ??
false negatives
- substances which are present but not detected by the lab
- ranges from 10-30%
- a negative test does not rule out a toxic agent being present
Describe a false positive
detection of therapeutic medications not contributing to the toxic clinical presentation
describe some other lab investigations
- ECG - arrhythmia, QT interval
- abdominal x-ray (radio-opaque pill ex. iron)
- urine osmolality - osmolal gap (ex. ethylene glycol)
- arterial blood gas - acidosis
- electrolytes
List some management strategies
- Supportive care
- Empiric Tx for altered mental status
- Decrease absorption of toxin
- Increase elimination of toxin
- Antidote
Describe the potential treatment to be considered for patient with altered mental status from a suspected drug overdose
1) Dextrose 0.5-1 g/kg of D50W for an adult - to diagnose and treat or exclude hypoglycaemia
2) Thiamine 100mg IV for an adult (usually unnecessary for a child) to prevent or treat Wernicke-Korsakoff syndrome
3) Naloxone 2mg IV for adults and children with respiratory compromise
4) Oxygen
List 4 ways to decrease absorption of a toxin
- Orogastric lavage
- Oral activated charcoal
- Whole bowel irrigation (flushing things through, not giving drugs a chance to be absorbed)
- Emesis with syrup of ipecac (not effective, not really used anymore)
List 4 ways to increase elimination of a toxin
- Hemodialysis (only if an agent is dialyzable)
- Charcoal hemoperfusion (useful for theophylline and phenobarbital)
- Multiple dose oral charcoal (charcoal binds to drug, and there is then 0 concentration in stomach, then you have a concentration gradient and it can pull drug from blood back into stomach)
