0071643192.pdf

(Barré) #1
TOXICOLOGY

A 21-year-old male is brought in by the police after being found running
naked in the park on a hot summer night. Physical examination reveals an
agitated patient chewing on the restraints and fighting to get loose. His
airway and breathing are intact and the nurse states that his pulse is “fast.” What
are the first actions to take in treating this patient?
Sedation with benzodiazepines and temperature control are essential with
the undifferentiated sympathomimetic patient. Although it would be ideal to
know what he took, determining the temperature and reversing the psychomo-
tor agitation are of paramount importance.

SYMPATHOMIMETICS

The sympathomimetic toxidrome may result from exposure to any of the
following:


■ Prescription medications: ADD/ADHD medications (Ritalin, Adderall)
■ Over-the-counter medications and herbal preparations: Ephedrine, pseu-
doephedrine, Ma Huang
■ Illicit drugs: Cocaine, methamphetamines


MECHANISM/TOXICITY


Excessive epinephrine or norepinephrine due to:


■ Increased release from α- and β-adrenergic receptors or
■ Decreased enzymatic breakdown or
■ Decreased reuptake
■ Cocaine→Na+channel blockade causing wide complex dysrhythmias.


SYMPTOMS/EXAM


■ Agitations, hallucinations
■ Tachycardia, hypertension
■ Hyperthermia with diaphoretic skin
■ Mydriasis
■ Muscular rigidity


DIAGNOSIS


Clinical diagnosis based on exposure history and physical exam
ECG to establish rhythm and screen for ischemic changes
CT of abdomen and pelvis may be indicated if body packer or stuffer.


TREATMENT


■ Supportive care
■ Passive and active cooling measures, as needed
■ Intravenous hydration
■ Benzodiazepines: For sedation, hyperthermia, tachycardia, seizures, mus-
cular rigidity
■ Sodium bicarbonate: For wide complex dysrhythmias
■ Avoid
■ β-Blockers due to concern for unopposed α-receptor stimulation


Sympathomimetic
toxidrome:
Agitation
Tachycardia
Hypertension
Large pupils
Diaphoretic

Diaphoretic, not dry, skin is
the key to differentiating the
sympathomimetic toxidrome
from the anticholinergic
toxidrome.
Free download pdf