Barone Lecture

Fentanyl and Meth

1. Name, telephone number, address, age, weight.
2. Name of substance, approximate quantity. (May be helpful?)
3. Time of ingestion or exposure, route.
4. Assessment of severity.
5. Ipecac is no longer recommended (unless transport is not available).
6. If patient is symptomatic or the potential for the development of symptoms is present, refer to closest hospital with all incriminating containers.

Treat the patient, not the poison; ABCs (Airway, Breathing, Circulation)

Respiratory complications are the major factors leading to death in overdose patients. A patent airway must be established before other lifesaving measures are undertaken. Intubation of the patient may be required.

Evaluate the rate, depth, pattern of breathing and signs of cyanosis. Adequate ventilation must be maintained and may require the use of oxygen and mechanical ventilation.

Evaluate cardiovascular function by the presence of pulse and blood pressure.
Perform advanced cardiac life support as necessary to maintain cardiac output.
In the presence of hypotension with a functional myocardium, the administration of
fluids is recommended.
If fluid therapy fails to sufficiently increase the pressure, the use of a catecholamine such as dopamine is recommended.

Judging the severity of an overdose or poisoning: history, neurological status, and physical evaluation.
a. history - one must keep in mind that overdose patients are notoriously poor historians. Less than 50% reliable. Caution with using LD50's to determine severity of poisoning.
DO NOT GET INTO THE SINGLE TOXIN MINDSET!!
b. evaluate neurological status - depressed or stimulated.

0-4 scale; goes from good to really bad as numbers increase

1+ Restlessness, irritability, insomnia, tremor, hyperreflexia, sweating, mydriasis, flushing.
2+ Confusion, hyperactivity, hypertension, tachypnea, tachycardia, extrasystoles, sweating, mydriasis, flushing, mild hyperpyrexia.
3+ Delirium, mania, self-injury, marked hypertension, tachycardia, arrhythmias, hyperpyrexia.
4+ Above plus: convulsions, coma, circulatory collapse.

vital signs (BP; RR; HR)
skin color (any cyanosis or tr
muscle tone
DTR's (deep tendon reflex)
abnormal movements
pupils – fundi
-pinpoint (heroin or opioid of some sort, meperidine [causes eye dilation w/ opioid effects])
-dilated and reactive (cocaine, sympathomimetics)
-dilated and unreactive (anticholinergic [psychoactive medications], scopolamine, atropine)
-nystagmus (horizontal) (antiseizure meds or alcohol)
-nystagmus (vertical and horizontal) (PCP)
cardiovascular
lungs (lung edema [likely opioid if not cardiogenic]

every OD gets an IV line!

Used in patients with symptoms consistent with narcotic (including propoxyphene, methadone) overdose. Symptoms include coma, lethargy, miosis, hypotension, respiratory depression. Naloxone is a relatively specific pure narcotic antagonist. Will reverse the respiratory and central nervous system depression.

IV narcotic antagonist; t1/2 = 4-8 hours. Problem of withdrawal in patients

Coma cocktail; if patient is comatose or stuperous. Admin 50 mL (1-2 amps). May do rapid Dextrostix at time of IV placement

Used in BZD overdose

prevent aspiration; Trendelenburg with head turned to the side. Dependent upon level of consciousness and presence or absence of gag reflex

Blood as Needed.
ABGs, E-lytes, ETOH
*Tox Screen*
Every OD gets an alcohol level and acetaminophen level
Anion Gap – useful in helping identify unexpected sources of acidosis.
AG = Na – (HCO3 + Cl) Normal AG is 12 (approx)

AT MUDPILES is the pneumonic
Alcohol
Toluene
Methanol
Uremia
Diabetic Ketoacidosis
Paraldehyde
Iron, Isoniazid
Lactic Acidosis
Ethylene Glycol
Salicylates, Strychnine

urine screen (clinicians must know what assays are on screen)
gastric contents
plasma screen
specific serum assay

presently recommended over emesis and gastric lavage in most clinical situations.

alkaloids cephaeline and emetine; produce vomiting through a biphasic mechanism. No longer recommended

Most recent studies indicate that emesis with ipecac only removes about one-third of stomach contents. (No longer recommended).

Significant cardiotoxicity reported with ipecac extract, not the syrup, except in ipecac syrup
abuse. Slight CNS depressions, diarrhea with syrup. May be abused by patients with eating
disorders.

Ipecac was recommended as long as 6 hours after the ingestion due to a possible decrease
in gastric motility produced by certain drugs and the clumping of tablets forming relatively
insoluble complexes.

1. Comatose or CNS depression
2. Loss of gag reflex
3. Convulsing
4. Acids or alkalis
5. Hydrocarbons (?)

Time Involvement: This procedure requires that the patient be under medical
supervision, such that valuable time may not be lost in retrieving an ingested toxin
during transport of the patient to the hospital.

Side Effects: Rare, though aspiration and laryngeal spasm have been reported.

Indications for Gastric Lavage:
1. comatose level III-V
2. loss of gag reflex
3. ipecac failure
4. convulsing patient
5. ingestion of large quantities of hydrocarbons???

1. In patients who cannot adequately protect their airway, (comatose, convulsing, loss
of gag reflex, volatile liquids?) endotracheal intubation with a cuffed tube is mandatory.
2. The patient should be placed in a lateral position in Trendelenburg position to minimize the possibility of aspiration.
3. A large bore tube should be passed and placement should be checked prior to fluid
instillation. Do not lavage with a nasogastric tube because it will be ineffective.
4. Aspiration and lavage should be instituted using 200-300 ml aliquots of water in adults and 100-200 mls. of water - alternating with normal saline in children. Lavage should be continued for a minimum of 3 liters of fluid or until the return is clear.

first line; routine treatment in all overdose situations with certain considerations:

Acetaminophen - charcoal may bind the antidote but the clinical importance is negligible. Would give charcoal within the first four hours after the ingestion, especially in mixed overdoses and unclear history.

Has little adsorbing effect on alcohols, cyanide and small molecular weight
ions (i.e. lithium). Use in the possibility of multiple ingestions.

should not be substituted for the powder as the tablet compaction diminishes the surface area, thus the adsorptive capacity which is not revisable upon crushing or chewing the tables.

5-10x weight of ingested substance; best multi-dose data for theophylline, phenobarbital, phenytoin, and salicylate poisoning. Recommend dosing q4-6 hours

non-toxic and if aspirated, the particles remain inert and do not produce an inflammatory reaction.

increase the gastrointestinal transit rate, thereby minimizing the absorption of the toxic substance.

not of consequence

Drugs that are largely eliminated renally offer an opportunity to hasten their excretion.
When performing this procedure, careful monitoring of fluid intake and urine output are essential to minimize the risks of fluid overload.

In most physiologic systems, passive reabsorption across all membranes can only occur in the unionized form of weak acids and bases.

Theoretically useful in situations involving amphetamines or phencyclidine

Acidifying agents
Ammonium chloride - 0.1 gm/kg/day in 4 divided doses or 1-2 grams q6h IV or PO
Ascorbic Acid - 1-2 grams IV q6h IV or P.O.
Monitor urine and blood pH. Goal is to maintain a urinary pH of 4-5.

Useful w/ phenobarbital, salicylates, and isoniazid

Alkalinizing Agent
Sodium bicarbonate - 1-2 mEq/kg IV. Goal is urine pH of 7.5- 8.0
Monitor urine and blood pH

The utilization of peritoneal or hemodialysis in overdose situations is ranked second to intensive supportive care

Dialysis removes solutes and drugs from the blood into a dialysate solution by osmotic diffusion across a semi-permeable membrane. The efficiency in removing a drug by dialysis is dependent upon properties of the drug.
a. volume of distribution (cut off < 1L/kg)
b. rate of equilibration from tissues
c. protein binding
d. molecular weight
e. dialysis clearance

1. Severe clinical intoxication with abnormal vital signs. Often this will include hypotension despite fluid replacement, apnea or sever hypothermia, or a combination of these findings.
2. Ingestion and probable absorption of a potentially lethal dose. This is best determined after gastric lavage has been completed.
3. A blood level that is in the potentially fatal range.
4. The presence of a significant quantity of a circulating toxin which isv metabolized to a more noxious substance. The metabolic conversions of methanol to formaldehyde and ethylene
glycol to oxalic acid are typical examples.
5. Progressive clinical deterioration while the patient is under care medical management.
6. Prolonged coma with its potential hazards, such as aspiration pneumonia, septicemia from infect I.V. sites, and peripheral neuropathy secondary to pressure ischemia.
7. Poisoning by agents known to produce delayed toxicity. Examples include paraquat and diquat.

a. salicylates
b. methanol
c. ethylene glycol
d. long acting barbiturates
e. lithium
f. theophylline