looking for radio-opaque ingestions (eg, leaded
paint chips or toys, batteries, selected drug packets) as
indicated to help complete the work-up.
items to help identify the possible toxin. A thorough physical
exam including careful attention to the patient's mental
perature, and moisture may help classify the patient's
presentation into a specific toxidrome. Use the ancillary
studies described previously to help clarify the diagnosis and
guide further management (Figure 54-1).
The treatment of poisoned patients can be broken down
into a very systematic approach outlined by the mnemonic
ABCDEFGH. First and foremost, initiate aggressive
supportive care. The airway and breathing must be secured
and addressed without delay. Intubation may be prevented
Supportive care: Address ABC's, IV
ccess, supplemental 02- cardiac monitor
Lab studies, ECG, identify toxidromes,
Consider enhanced elimination:
• Mu lti-dose activated charcoal
Consider focused antidotal therapy
Figure 54-1 The poisoned patient
diag nostic algorithm. ABCs, airway,
breathing, and circu lation; ECG,
electrocard iogram; IV, intravenous.
with the successful use of a focused therapy such as
naloxone in opioid toxicity or supplemental dextrose in
hypoglycemic patients. Likewise, correct any circulatory
compromise in the form of hypotension or bradycardia
with standard fluid and/or vasopressor administration. Pay
careful attention to the core temperature. Aggressively and
The basic goal of decontamination is to remove the poison
from the patient and the patient from the poison. Attempt
decontamination as early as possible to achieve maximal
benefit. Washing a patient's skin with soap and water to
prevent further absorption and/or prevent harm to the
charcoal (1 g/kg or a 10:1 ratio of charcoal to toxin) can be
lavage in patients who present very early (within 1 hour)
warrant lavage regardless of the timing of ingestion (eg,
massive colchicine overdose). Contraindications to gastric
intracranial pressure, aspiration, and esophageal rupture.
Whole-bowel irrigation with polyethylene glycol
(GoLYTELY), given at a rate between 0.5 L/hr (pediatrics)
and 2 L/hr, may help to "flush" toxins that won't bind to
charcoal (eg, leaded paint chips) out of the GI tract and
therefore limit total absorption. Contraindications to
whole-bowel irrigation include hemodynamic instability
(hypotension = lack of GI perfusion) and decreased bowel
sounds (impaired GI motility). Of note, pulmonary aspira
tion is the most common adverse side effect for all forms of
GI decontamination, and patients must have an intact air
way for these procedures to be pursued.
There are several different modalities available to
enhance the elimination of poisons. Hemodialysis is ideal
for smaller-sized poisons with small volumes of distribution
( <1 L/kg) and low degrees of protein-binding. Ideal agents
for hemodialysis include aspirin, toxic alcohols, and lithium.
Hemodialysis should also be performed in all patients with
profound acidemia regardless of the etiology. Alkalinization
of the urine is commonly initiated for ingestions of weak
acids such as aspirin and phenobarbital. The proposed
mechanism depends on increasing the urinary pH by giving
doses of intravenous (IV) sodium bicarbonate. Circulating
toxins will be preferentially converted to their conjugate
bases in the alkaline environment and consequently trapped
in the renal tubules, where they will be excreted in the urine.
Alkalinization can also benefit patients in select cases ( eg,
salicylate overdose) by keeping the poison preferentially out
of the CNS, as the ionized form cannot enter through the
blood-brain barrier. Finally, multiple doses of oral activated
charcoal (MDAC) can be administered to patients poisoned
with select agents including theophylline, phenobarbital,
circulating toxins back into the GI tract where they are
bound to the charcoal and excreted. MDAC can also be
employed to further decontaminate the gut of agents that
have erratic and prolonged absorption ( eg, salicylates, val
polyethylene glycol) can cause marked fluid and electrolyte
shifts, resulting in significant morbidity and/or mortality.
Antidotal therapy is important and necessary when
managing the poisoned patient, but should never take
priority over the supportive measures already mentioned.
Examples of selected focused therapy along with general
indications are listed in Table 54-3. The final portion of the
Table 54-3. Specific antidotes for toxicologic agents.
Hydrofluoric acid, calcium channel
Calcium channel blocker, � blocker
Oxidizing chemicals (nitrites, benzocaine,
Refractory hypoglycemia after oral
TCA, tricyclic antidepressant.
management algorithm includes G and H. This is a
reminder for clinicians to never hesitate in calling their
regional poison center ( 1-800-222-1222) for assistance
during any point in the care of the poisoned patient.
Getting help early may facilitate a more focused work-up,
prevent unnecessary laboratory and/or diagnostic studies,
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