EM E2: Toxicology

What is part of decontamination management of toxic emergencies?

intubate, gastric lavage (< 1-2 hrs of ingestion), charcoal, clean skin

What can be used for resp depression if suspected opiate ingestion?

Naloxone 2mg IM/IV

What can be used of alcoholism or malnutrition?

Thiamine 100 IM/IV

What do you give for suspected hypoglycemia/

Dextrose 50%

Alkaline diuresis can help enhance elimination of which drugs?

*sodium bicarbonate in D5W

salicylates, phenobarbital

Hemodialysis can enhance elimination of which drugs?

ASA, Lithium, toxic alcohols

Which stage of APAP toxicity:

anorexia, N/V, malaise, may be asx, rise in serum transaminase levels at 12 hrs post ingestion

Stage 1 (1-24 hrs)

Which stage of APAP toxicity:

RUQ pain, anorexia, N/V, continued inc in serum transaminase levels

Stage 2 (24-72 hrs)

Which stage of APAP toxicity:

sequelae of hepatic necrosis including jaundice, renal failure, coagulopathy, hepatic encephalopathy, coma, and death

Stage 3 (72-96 hrs)

When is it most critical to get the level of plasma APAP?

4 hrs (or more)

Which pts require N-acetylcysteine for tx of APAP toxicity?

plasma level > 2000, 1000, 500 at hrs 4, 8, 12 respectively

You should initiate N-acetylcysteine for APAP toxicity if how much was ingested?

*continued tx depends on serum levels

> 7.5 g

When does N-acetylcysteine need to be given IV?

fulminant hepatic failure, high serum levels at 8 hrs post ingestion, unable to take PO, pregnant pt

What are sx of acute ASA toxicity?

vomiting, tachypnea, tinnitus, lethargy w/ acid-base changes

severe: coma, seizures, hypoglycemia, pyrexia, pulm edema, death from cerebral edema and cardiovascular collapse

What are sx of chronic ASA toxicity?

metabolic acidosis

What dose of ASA is considered toxic?

> 160 mg/kg

What is the tx for ASA toxicity?

activated charcoal, bowel irrigation, bicarb to correct acidosis, correct fluid deficit, prompt hemodialysis for serious intoxication

What agents can cause Anticholinergic toxicity?

Anticholinergics (atropine, benztropine), Antihistamines (meclizine, benadryl), Antipsychotics (thorazine, seroquel, zyprexa), Antispasmodics, Cyclic antidepressants, Mydriatics, Plants

What are sx of Anticholinergic toxicity?

flushing, dry skin and mucous membranes, mydriasis, AMS, fever, tachycardia

central: ataxia, disorientation, confusion, hallucinations, psychosis

What is the tx for Anticholinergic toxicity?

Physostigmine salicylate = antidote

GI decontamination, activated charcoal, benzo for seizure/agitation

What are sx of Digitalis toxicity?

confusion, depression, anorexia, N/V, diarrhea, yellow vision

What EKG changes are seen w/ Digitalis toxicity?

ST-T wave changes, heart block, PVCs, sinus arrest, accelerated junctional rhythm, atrial tachycardia w/ AV block, V tach, V fib

What is the tx for Digitalis toxicity?

Digibind for profound toxicity, life-threatening cases

supportive: fluids, electrolytes, control arrhythmias

What are sx of B-adrenergic Blocker toxicity?

*usually appear w/in 1-2 hrs ingestion

bradycardia, bronchospasm, hypotension, pulm edema, AV block, widening QRS, sinus arrest, asystole, CNS manifestations, hyperkalemia, hypoglycemia

What is the tx for BB toxicity?

lavage, charcoal, correct electrolyte abnormalities, Diazepam if seizing, Glucagon may reverse bradycardia and hypotension

What are sx of CCB toxicity?

initially hypotension and bradyarrhythmias; N/V, CNS depression, Hyperglycemia d/t suppression of insulin release

What is the tx for CCB toxicity?

lavage, charcoal, fluid challenge

can use: CaCl, atropine, dopamine, isoproterenol, epinephrine, temp pacing as needed

What are sx of Clonidine toxicity?

mimic narcotic overdose: bradycardia, hypotension, resp distress, miosis, stupor, coma, hypoactive DTR’s

What is the tx for Clonidine toxicity?

lavage, charcoal, fluids, intubation

vasopressors, atropine, naloxone (Narcan)

What are sx of Clonidine withdrawal?

agitation, abd pain, N/V, tachycardia, diaphoresis, mydriasis, HTN crisis

What is the tx for Clonidine withdrawal?

both a- & B- adrenergic antagonists (phentolamine & propranolol)

What are sx of Nitrate and Nitrite toxicity?

vasodilation → orthostatic hypotension, light-headedness, syncope, tachycardia, diaphoresis

Methemoglobin → hypoxia

What is the tx for Nitrate and Nitrite toxicity?

lavage, charcoal, airway, O2, fluids, Trendelenburg position, vasopressors

Methylene blue for methemoglobin > 40%

What are sx of TCA toxicity?

hypotension, anticholinergic effects (AMS, seizure, tachycardia, mydriasis)

What EKG changes are seen w/ TCA toxicity?

PR, QRS, QT become prolonged, AV conduction blocks, V tachy or V fib

What is the tx for TCA toxicity?

*should be aggressive

cardiac monitor, baseline EKG, charcoal, lavage

NaHCO3 for acidosis, QRS > 100 ms, arrhythmias, hypotension

fluids, vasopressors, Lorazepam, MgSO4

What do sx of MAOI toxicity depend on?

time of presentation -usually w/in 24 hrs, but can take up to 32 hrs, co-ingestions, d/t serotonin excess

Which phase of MAOI toxicity:

lasts 6-12 hrs d/t gradual accumulation of NE

Phase 1

Which phase of MAOI toxicity:

catecholamine surge → CNS excitation

Phase 2

Which phase of MAOI toxicity:

hypotension and CNS depression

Phase 3

Which phase of MAOI toxicity:

rhabdomyolysis, renal failure, pulm edema, MI, DIC

Phase 4

What EKG changes are seen w/ MAOI toxicity?

sinus tachy, T wave changes

What is the tx for MAOI toxicity?

intubation, lavage, charcoal, fluids, maintain euthermia, benzo

Individuals demonstrate signs of GI toxicity after ingestion of how much iron?

20 mg/kg

Individuals demonstrate moderate intoxication when how much iron is ingested?

40 mg/kg

Individuals experience severe toxicity (may be lethal) after ingesting how much iron?

60 mg/kg

What is one of the leading toxicological causes of death in children < 6 yo?

iron

What are sx of iron toxicity?

GI sx (V/D) -especially hemorrhagic, hyperglycemia w/ metabolic acidosis, abd pain, gastroenteritis

T/F: Pts w/o vomiting most likely did not ingest a toxic dose of iron

True

Which stage of iron toxicity:

w/in 6 hrs, N/D, abd pain, gastroenteritis, may be hemorrhagic, fluid and bloss loss, edema, hypovolemia, shock, death

Stage 1 (gastrointestinal)

Which stage of iron toxicity:

resolution of GI, appear to improve and recover, last 6-12 hrs (up to 24), metabolic acidosis, hypotension, coagulopathy, some pts skip this phase

Stage 2 (latent)

Which stage of iron toxicity:

metabolic acidosis, CV sx, venous pooling, edema, CNS sx, stupor, coma, most pts die during this phase; can last up to 2 days

Stage 3 (metabolic/cardiovascular)

Which stage of iron toxicity:

elevated liver enzymes and bilirubin levels, coagulopathy, hepatic dysfunction, hypoglycemia

Stage 4 (hepatic)

Which stage of iron toxicity:

scarring of the healing GI tract, stomach or intestines may be affected and cause an obstruction, usually weeks after severe poisoning

Stage 5 (delayed)

Serum iron levels need to be drawn when?

at least 4 hrs post ingestion; > 6 hrs may underestimate toxicity

How do iron tablets show up on KUB?

radiopaque

What is the tx for iron toxicity?

GI decontamination, bowel irrigation, deferoxamine chelation = mainstay

What are sx of lead toxicity?

peculiar sx, irritability, sleeplessness, excess lethargy, poor appetite, HA, abd pain, ± V, constipation, vague changes in activity level

What are possible physical findings of lead toxicity?

iron deficiency, pale, anemia, can precipitate gout attacks, peripheral neuropathy (foot or wrist drop)

What testing is done for lead toxicity?

whole blood lead level (BLL)

*> 10 = +, and consequential

What lead levels require removal from exposure, repeated testing, and follow-up?

10-20 mg/dL

What is the tx for lead toxicity?

IV drip of NS, whole-bowel irrigation w/ polyethylene glycol, immediate chelation therapy

What are sx of benzo toxicity?

drowsiness, ataxia, nystagmus, dysarthria, coma, delirium, death

Which benzo is 10x as potent as diazepam, produce disinhibition, amnesia, and prolongs the effects of heroin, methadone, and alcohol?

Flunitrazepam-Rophynol “roofies” -date rape drug

What is the antidote for benzodiazepines OD?

Flumazenil

What are the 2 most frequently abused opioids in the US?

Heroin and Methadone

What are the hallmark sx of opioid OD?

coma, respiratory depression, miosis

What is the tx for Opioid toxicity?

intubation, O2, charcoal, supportive, Naloxone (Narcan)

What are sx of hallucinogen toxicity?

*onset 30-60 min w/ 4-8 hr duration

sympathetic stimulation, dilated pupils, diaphoresis, panic attacks, illusions, tachycardia, inc DTR’s

What is the tx for Hallucinogen toxicity?

GI decontamination for mescaline and psilocybin, but not LSD

cardiac monitor, pulse ox, verbal reassurance, benzos and haloperidol for pts w/ severe agitation

What are sx of Cocaine toxicity?

CNS stimulation, tachycardia, hypertension, hyperthermia, muscle twitching, seizures, ventricular dysrhythmias; CNS, cardiac, resp arrest

What is the tx for Cocaine toxicity?

supportive, fluids, Diazepam

*do NOT give BBs

What are sx of Amphetamine toxicity?

*ranked 1+ to 4+

restlessness, irritability, seizures, coma, insomnia, tremor, diaphoresis, mydriasis, tachypnea, N/V, nystagmus, tachycardia, hyperpyrexia, delirium, arrhythmias

What is one of the most commonly synthesized illicit drugs?

crystal meth “ice” “crank”

*onset is minutes, lasts 2-24 hrs

What amphetamine is popular at raves and provides low dose euphoria?

MDMA -ecstasy “Molly”

*lasts 4-6 hrs

What is the tx for Amphetamine toxicity?

supportive, monitor, Benzos, Labetalol for HTN, dopamine or NE for hypotension, tx MI, dysrhythmias, hyperthermia, rhabdo

What are sx of neuroleptic toxicity?

hypotension, tachycardia, hyperthemia, dry skin, urine retention, mydriasis, CNS and resp depression, dystonia, akathisia, motor disorders

What EKG changes does Quinidine cause?

prolonged QT and PR, Torsades

Which Neuroleptic drugs have more anticholinergic and anti-adrenergic effects?

low potency drugs (Thorazine, Serentil)

Which Neuroleptic drugs cause more anti-dopamine effects?

high potency drugs (butyrophenones and thioxanthenes)

What is the tx for neuroleptic toxicity?

monitor, pulse ox, charcoal, lavage, tx arrhythmia, IV fluids

What are sx of sedative-hypnotic toxicity?

*barbiturates and Benzos MC

CNS depression

What is the tx for Sedative-Hypnotic toxicity?

ABC’s, lavage w/in 1 hr, charcoal, enhance elimination w/ alkaline diuresis, Flumazenil

When do Lithium levels peak?

0.5-3 hrs after ingestion

What serum Lithium level causes acute mania?

0.6-1.2 mEq/L

(0.5-0.8 = maintenance)

What can Lithium cause?

diabetes insipidus, dec anion gap, hyper or hypo kalemia

What are sx of Lithium toxicity?

<1.2: fine tremor, dry mouth, polyuria, nausea

1.2-2: vomiting diarrhea

2-2.5: blurred vision, muscle weakness, fasciculations, dizziness, vertigo, ataxia, slurred speech, confusion, scotomas

2.5-3: myoclonic twitches, incontinence, stupor, EKG changes

3-4: seizures, arrhythmias

>4: hypotension, peripheral vascular collapse

When should you draw serum Lithium levels?

acute: 2 hrs post ingestion

chronic: 6-12 hrs

*repeat q 4 hrs

What is the tx for Lithium toxicity?

lavage, monitor, kayexalate, fluid, correct, electrolyte deficits

severe: hemodialysis

What are sx of insecticide toxicity?

cholinergic syndrome: salivation, lacrimation, urination, diarrhea, GI cramps, emesis

bradycardia, miosis, bronchorrhea, muscle weakness, paralysis, fasciculations

What is the tx for insecticide toxicity?

remove clothes, wash skin, GI decontamination, activated charcoal, cholestyramine, contact poison control or medical toxicologist

What are sx of alcohol toxicity?

CNS and resp depression, hypoglycemia

What is the tx for alcohol intoxication?

thiamine, folate, multivitamin, Mag, D5 ½ NS

What are sx of Methanol intoxication?

severe acidosis, CNS depression, classic snowstorm blindness

What is the tx for Methanol poisoning?

EtOH, narcan, ethanol, fomepizole, dialysis

What are sx of Ethylene Glycol toxicity?

hypocalcemia, CNS, CVS, renal effects

What is the tx for Ethylene glycol & Isopropanol toxicity?

EtOH, Fomepizole, Dialysis