Most common cause of death in a poisoned patient
Types of poisoning
Intentional (suicide and roofies), accidental (illicit drugs, kids, elderly), envenomations and terrorism.
Trauma, dosage, co-ingestions, PMH, psychiatric history, collaterals (contacts, things found on scene). If things don’t add up think about tox.
“Septic” old people without evidence of infection
26 year old man is slumped over his desk with a bottle of unlabeled pills in his backpack. He has a history of back pain. Physical exam shows elevated HR, T, BP, big pupils dry skin and is obtunded. ECG shows What is his toxidrome?
Anticholinergic toxidrome. Note the tachycardic rhythm, upright R wave on aVR (sign of Na channel blockade), wide QRS complex and long QT. This is pathogmonic for TCA overdose (amitriptyline).
A 66 year old woman presents with abdominal pain, diarrhea and vomiting. She said symptoms came up after eating a “bean” from a roadside plant. She has a history of depression. HR is elevated, she is dehydrated, normal mental status and abdomen is very tender. What beans could cause her symptoms?
Castor bean (Ricin) poisoning, supportive care usually results in resolution.
A 21 year old woman is brought in to see you after sending suicidal texts. No evidence of ingestion of poison is present. Physical exam reveals a sad appearing woman and nothing else. What lab might you pull?
Acetaminophen levels because overdose is clinically silent. Tx with N-acetyl cysteine.
Tox physical exam
Trauma, vitals, pupils, skin, bowel sounds and mental status combined with the history will give you your “toxidrome”.
Cocaine overdose toxidrome
Elevated HR, T, BP (sympathomimetic). Hyperactive mental status. Dilated pupils. Diaphoretic skin.
Jimson weed overdose toxidrome
Increased HR, T, BP (anti-cholinergic). Hyperactive mental status. Dilated pupils. Dry skin.
Opiate overdose toxidrome
Pinpoint pupils, bradypnea
PCP overdose toxidrome
Rotatory nystagmus (also with alcohol)
Common overdose that is clinically silent.
Useful acute tests
Acetaminophen levels (in suicidal patients), ECG, chemistry/blood gas.
Least useful acute tests
Drug levels and urine tox screens. Lots of false +, false - and may be used normally and not causing symptoms.
Treatment principles of poisoning
Decontamination, gastric lavage (usually not effective), whole bowel irrigation (usually not effective), emetics (often contraindicated due to aspiration), dialysis (most effective), charcoal (good if taken within 30 min of ingestion), supportive care (fluids, electrolytes, respiratory support).
Commonly used antidotes
Snake bites, scorpion stings, digoxin overdose, N-acetylcystein for acetaminophen overdose.