Tox

Question 1

For what substances is activated charcoal not effective?

Answer 1

PHIAL
Pesticides
Hydrocarbons
Iron/metals
Alcohols
Lithium

Question 2

What are the indications for hyperbaric treatment in CO poisoning?

Answer 2

• COHb >25% (15% in pregnancy)
• neuro deficits or AMS
• syncope
• myocardial ischemia
• CV instability or arrhythmias
• severe acidosis (pH < 7.1)

Question 3

What does hydrogen fluoride exposure cause?

Answer 3

Hypocalcemia, hypomag, dysrhythmias
Tx: calcium chloride
Used for glass etching, rust removal

Question 4

What medications cause methemoglobinemia?

Answer 4

Nitrates
Dapsone
Benzocaine spray
Phenazopyridine

Question 5

What are the indications for digibind in digoxin toxicity?

Answer 5

K >5
Ventricular dysrhythmia
Bradycardia refractory to atropine
Dig level >10 in adults, >4 in peds

Question 6

What are the symptoms of MAOI toxicity?

Answer 6

Hypertensive emergency, dysrhythmias, DIC

Question 7

How much is typically a toxic dose of Tylenol?

Answer 7

150 mg/kg

Question 8

When is methylene blue indicated for methemoglobinemia?

Answer 8

When patient is symptomatic or MetHb > 20%

Question 9

When is cyanide poisoning seen?

Answer 9

House fires, exposure to nitroprusside, metal polish, certain insecticides

Question 10

What are the sx and lab findings in methanol ingestion?

Answer 10

Intoxication, renal failure, blindness
Lactic acidosis w/ elevated AG
Tx: HD, fomepizole, folinic acid

Question 11

What are the sx and lab findings in ethylene glycol ingestion?

Answer 11

HypoCa, renal failure, urine contains calcium oxalate crystals, acidosis and elevated AG
Tx: ethanol, fomepizole, HD, thiamine and pyridoxine

Question 12

What are the sx and lab findings in isopropyl alcohol ingestion?

Answer 12

Intoxication, hemorrhagic gastritis, hypotension, elevated AG + ketosis without acidosis
Tx: supportive care

Question 13

What is the lethal dose of aspirin?

Answer 13

500 mg/kg

Severe toxicity at > 300 mg/kg

Question 14

What is considered a massive overdose of ibuprofen?

Answer 14

450 mg/kg (clinically significant is 100 mg/kg)

Question 15

What are the sx of dextromethorphan toxicity?

Answer 15

Similar to PCP - visual hallucinations, rotary nystagmus, tachycardia, mydriasis, hyperthermia, resp despression, rhabdo
Can cause serotonin syndrome if co-ingested w/ SSRI

Question 16

What is the fatal dose of iron?

Answer 16

60 mg/kg

Question 17

What are indications for deferoxamine after iron ingestion?

Answer 17

• iron level > 500 mcg/dL (or >350 in a symptomatic patient)
• intractable vomiting/diarrhea
• anion gap metabolic acidosis
• severe AMS
• shock

Question 18

At what blood lead level is dimercaprol indicated?

Answer 18

70, should follow dimercaprol w/ CaNa2EDTA

Question 19

What is the treatment for beta blocker toxicity?

Answer 19

• activated charcoal (if within 1-2 hours)
• calcium gluconate or chloride
• glucagon (increase cardiac contractility)
• high-dose insulin (1-10 U/kg/hr)
  Atropine does not work!

Question 20

What are the sx and tx of valproic acid toxicity?

Answer 20

Sx: n/v, sedation, resp depression, elevated ammonia
Tx: L-carnitine

Question 21

What are the components of salicylate toxicity treatment?

Answer 21

1) aggressive IVF
2) activated charcoal (if within a few hours of ingestion)
3) bicarb gtt for alkalinization of urine - bolus 1-2 amps + infusion of 3 amps in 1L D5W running at 2-3x maintenance (goal urine pH > 7.5)
4) correct hypokalemia
5) dialysis if needed

Question 22

What are indications for dialysis in salicylate toxicity?

Answer 22

• clinical deterioration or failure to improve in spite of other treatment
• failure to sufficiently alkalinize urine or serum
• renal insufficiency or failure
• severe acid-base disturbance
• AMS
• acute lung injury
• strongly consider in any pt w/ serum salicylate > 100

Question 23

What are the symptoms of TCA toxicity?

Answer 23

Sedation, antimuscarinic effects (similar to atropine - tachycardia, hyperthermia, delirium, dry mouth, urinary retention), slurred speech, clonus/hyperreflexia, seizure, cardiotoxicity

Question 24

What EKG changes are seen in TCA toxicity?

Answer 24

Prolonged PR, widened QRS, terminal R wave in aVR, QT prolongation, Brugada pattern

Question 25

What is the treatment of TCA toxicity?

Answer 25

• activated charcoal (if within 1 hr of ingestion and awake), give even if asymptomatic
• bicarb 1-2 amps PRN for conduction abnormality or ventricular dysrhythmia (most antiarrhythmics are contraindicated!)
• benzos PRN for seizures

*most serious complications will occur within 6 hours of ingestion

Question 26

What drugs are dialyzable in overdose?

Answer 26

Aspirin
Toxic alcohols
INH
Lithium
Barbiturates
Valproic acid
Metformin-induced lactic acidosis

Question 27

What are the 4 stages of iron poisoning?

Answer 27

0.5-6 hrs: n/v/d, abdominal pain, hematemesis
4-12 hrs: progressive systemic deterioration (hypoperfusion, acidosis) as GI sx resolve
6-72 hrs: coma, lactic acidosis, coagulopathy, shock
12-96 hrs: hepatic failure

Question 27

At what serum salicylate level do symptoms of toxicity occur?

Answer 27

Sx begin at 40-50

Level > 100 is life-threatening

Question 27

What is the treatment for iron overdose?

Answer 27

• whole bowel irrigation (PEG 2 L/hr via NGT)

- deferoxamine 5 mg/kg/hr