0071643192.pdf

TOXICOLOGY

■ Hypertension

■ Diminished bowel sounds, decreased defecation

■ Urinary retention

DIFFERENTIAL

■ Encephalitis

■ Neuroleptic malignant syndrome

■ Sympathomimetic toxicity may have similar presentation, but skin is typi-

cally moist (not dry).

DIAGNOSIS

■ Clinical diagnosis is based on exposure history and physical exam.

■ Labs and imaging as needed to exclude nontoxicologic causes.

■ ECG used to screen for TCA toxicity.

TREATMENT

■ Supportive care

■ Passive and active cooling measures may be needed.

■ Benzodiazepines (for seizures, agitation, hyperthermia)

■ Intravenous hydration

■ Antidote=physostigmine.

■ Indications include tachycardia uncontrolled with standard therapy

and agitation uncontrolled with sedatives.

■ Avoid

■ β-Blockers

■ Sedatives with anticholinergic effects such as diphenhydramine or

antipsychotic agents

COMPLICATIONS

■ Rhabdomyolysis

■ May be the result of agitation, coma, or hyperthermia

■ Sedate with benzodiazepines to control psychomotor agitation and

hyperthermia.

■ Treat with intravenous fluids, follow CK, creatinine, as indicated.

Cholinergics

The cholinergic toxidrome is uncommon, but may result from exposure to

cholinergic agents (see Table 6.8).

MECHANISM/TOXICITY

■ Inhibition of the enzyme acetylcholinesterase →excess acetylcholine at

muscarinic and nicotinic receptors.

SYMPTOMS/EXAM

■ Altered mental status (delirium to coma), seizures

■ Increased secretions →lacrimation, salivation, sweating, bronchorrhea.

■ Bronchospasm

■ Miotic (constricted) pupils

■ Bradycardia (bradydysrhythmias may occur)

■ Urinary incontinence

■ Hyperactive bowel sounds and bowel incontinence (vomiting/diarrhea)

■ Muscle fasciculations

Anticholinergic toxidrome:

Mad as a hatter

Red as a beet

Dry as a bone

Blind as a bat

Hot as a hare

Seizing like a squirrel

Tachy as a pink flamingo

Full as a flask

Benzodiazepines are the

mainstay of therapy for

anticholinergic poisoning.

Cholinergic

toxidrome—

SLUDGE

Salivation/Sweating

Lacrimation

Urination

Defecation

Gastrointestinal distress

Emesis

plus

“The Killer Bs”:

Bradycardia

Bronchorrhea

Bronchospasm