Toxicology Emergencies Flashcards
What is addiction?
Compulsive engagement in rewarding stimuli despite adverse consequences
What is tolerance?
Diminished response to drug secondary to repeat use
What is dependence?
Adapted physiologic state d/t recurrent exposure to substance (results in withdrawal if ceased)
What does “sola dosis facit venenum” mean?
The dose makes the poison
-Paracelsus
Adage indicating basic principle of toxicology
Which drugs are opiates?
Heroin, Codeine, Hydrocodone (Vicodin, Norco), Oxycodone (Percocet, Oxycontin), Morphine, Hydromorphone (Dilaudid), Fentanyl, Duragesic, Methadone
What is heroin derived from?
Opium poppy
Common street names of heroin?
H, smack, boy, horse, brown, black, tar
Pathophys of heroin?
Introduced to blood stream –> converted to morphine by enzymes –> binds to opiate R’s in reward pathway –> stimulates dopamine release & pain pathway
Onset of heroin?
Seconds to minutes
Duration of heroin?
2-6 hrs
Heroin methods of use?
Injection, smoking, snorting
Effects of heroin?
Acute CNS & respiratory depression, constricted ‘pinpoint’ pupils, nausea
Treatment of heroin overdose?
-Acute OD: Narcan
-Observation to make sure long acting narcotic not involved
-Abscesses may need drainage
-Consider endocarditis
What is naloxone (narcan)?
Competitive opioid antagonist, blocking all opioid receptors
ROA of naloxone?
IV, IM, SC, endotracheal
Usual starting dose of naloxone?
0.4mg
(repeat doses of 0.4 mg/hr may be necessary)
Duration of naloxone?
30-60 min
What may narcan induce?
Vomiting and agitation
What is speedballing?
Simultaneous IV injection of heroin and cocaine
Common prescription opiates of abuse?
Vicodin (Hydrocodone), Percocet (Oxycodone), Fentanyl
Signs someone is abusing prescription meds?
May request pure forms or report allergy to tylenol/NSAIDs
Who may have non-intentional OD’s secondary to uncontrolled pain or poor liver/renal function?
All patients but especially elderly
Prescription opiate OD is ________ in onset and lasts _________
slower in onset and lasts longer
S/Sx of opiate withdrawal?
Mildly increasing temp, yawning, rhinorrhea, lacrimation, midriasis, vomiting, diarrhea, stomach cramps, myalgia, arthralgia, irritability
Treatment for opiate withdrawal?
-Clonidine (Catapres) 0.1-0.2mg PO or transderm patch x1wk prn
*hold for SBP <150
-Dicyclomine (Bentyl) 20mg q6hr prn cramps
-Loperomide (Imodium) 2mg q6hr prn diarrhea
-Hydroxyzine HCl (Atarax) 50mg q6hr prn anxiety/sleep
-Ibuprofen 600mg q6hrs prn pain
-Methadone program may be needed for long tx
Cocaine is a naturally derived CNS stimulant extracted/refined from what?
Coca plant
Common street names of cocaine?
Crack, freebase, coke, blow, rock, crank
Pathophys of cocaine?
Binds w/ Na+ channel –> inhibits Na+ conduction/blocks ion conduction w/in myocardial and nerve cells
Inhibits monoamine reuptake –> enhanced action of NE, Epi, Dopamine
Onset of cocaine?
seconds to min
Duration of cocaine?
20-40 min
Cocaine methods of use?
Snorting MC, PO, intranasal, IV, smoking
Effects of cocaine?
Euphoria, paranoia, inc. sexual stim, inc. energy, HTN, tachycardia, coronary artery vasospasm, ruptured AAA, cerebral bleed/infarct, pneumomediastinum, pneumothorax, pneumopericardium, bullous emphysema, pulm edema, bronchospasm, alveolar hemorrhage, pneumonitis, bronciolitis, pulm HTN
EKG of someone who is using cocaine may show what?
Prolonged QRS, QT & QTc intervals, STEMI, Vtach/Vfib
Treatment for cocaine overdose?
-Benzodiazepines (Lorazepam- Ativan) 1-3mg IV prn
-IV fluids replace volume loss or if rhabdo
-BP management: Nitroprusside, Nitroglycerin, Phentolamine (AVOID BB d/t unopposed a-adrenergic activity)
-Long term tx w/ support networks/therapy
Can you reverse cocaine with narcan?
No, cannot reverse like opioids
Is there are true withdrawal with cocaine?
No, more of a hangover (requires rest/time)
What is synthetic marijuana marked as OTC?
Incense, potpourri
Common street names of synthetic marijuana?
Spice, K2, fake weed, Yucatan Fire, Skunk, Moon rocks
Pathophys of synthetic marijuana?
Synthesized compounds bind more strongly to THC R’s than regular marijuana –> more powerful, unpredictable, dangerous effect
Onset of synthetic marijuana?
15-30 min
Duration of synthetic marijuana?
2-6 hrs
Effects of synthetic marijuana?
Severe agitation/anxiety, fast/racing heart, high BP, N/V, intense hallucinations/psychotic episodes, suicidal/harmful thoughts and actions, linked to development of pneumonia
Treatment for synthetic marijuana?
Benzodiazepines (Ativan), may need large doses, wait it out
What are bath salts derived from?
Khat plant
What are bath salts marketed as?
“bath salts”, plant fertilizer, insect repellent, pond cleaners, vacuum fresheners
Street names for bath salts?
Vanilla sky, Cloud nine, Ivory wave, Aura, Blizzard, Scarface
Pathophys of bath salts?
Active chemical acts on monamine NTs as dopamine-NE reuptake inibitors –> inc. in serotonin (& to lesser extent - Dopamine)
Bath salts methods of use?
Snorted MC, ingestion, injecting, smoking, rectal
Onset of bath salts?
30-90 min
Duration of bath salts?
2-4 hrs
Effects of bath salts?
Excited delirium, tachycardia, HTN, CP, paranoia, hallucinations, panic attacks, extreme agitation, rhabdo/renal failure
Bath salts are not detected by what?
DAU-8
Treatment for bath salt use?
Benzodiazepines (Ativan), may require larger dosing, wait it out
What are amphetamines?
Pharmaceuticals originally used as OTC bronchodilator, later for narcolepsy, Parkinsons, depression, weight loss (and used by soldiers, truck drivers, students, athletes)
Today used most for ADHD/ADD (Adderall)
Street names for amphetamines?
Crystal meth, speed, crank, ice, glass
Pathophys of amphetamines?
Stimulate release of dopamine and serotonin –> dopamine stores depleted resulting in depression/need for re-use
*long term use destroys dopamine & serotonin brain cells
Amphetamines methods of use?
IV, smoking, snorting, pill abuse (Adderall)
Onset of amphetamines?
quick high that lasts 5-30 min
Duration of amphetamines?
6-12 hrs
Effects of amphetamines?
Euphoria, inc. activity, inc BP/RR, hyperthermia, insomnia, unpredictable behavior, N/V, cracked teeth, sores, skin infections, seizures, sudden death
Long term: Parkinson’s, Alzheimers-like sx, paranoia, CVA
Treatment for amphetamines?
-Haloperidol (Haldol) 5-10mg IM for agitation
-Lorazepam (Ativan) 1-4mg IM/IV for agitation or seizure
-Labetalol 20mg IV for HTN/tachycardia q10min prn
What did CNS depressants have early use in?
Medical anesthetics, ETOH, withdrawal, narcolepsy
Common names for CNS depressants?
GHB, Rohypnol, rophie, G, liquid ecstasy, “date rape drug”
Pathophys of CNS depressants?
Impairs dopaminergic transmission (mech poorly understood)
Methods of use for CNS depressants?
Mostly PO
Onset of CNS depressants?
15-30 min
Duration of CNS depressants?
90 min (peak), 2-12 hrs
Effects of CNS depressants?
Euphoria, dec. inhibition, sleepiness/lethargy, muscle relaxation, disorientation, confusion, loss of balance, headache, N/V, hallucinations, seizures, amnesia, resp. depression
Tx for CNS depressants?
ABCDE’s (airway, breathing, circulation, disability, exposure)
-Any signs or hx of rape: SNAKE kit & police
-Supportive usually all that is needed until wears off
-SEVERE overdose: Physostigmine 1-2mg IV over 5min (rpt in 10-15 min prn)
How is activated charcoal made?
Wood heated to high temp and oxidized using acid and steam to make find particles (almost pure carbon) –> structure has huge surface area (50g = 10 football fields)
Charcoal acts as a sponge to absorb what?
Chemicals/meds not yet absorbed by GI tract/into circulation
What is charcoal usually given with?
Sorbitol (acts as laxative)
What is charcoal not useful for?
Corrosives/solvents, iron salts, lithium, boric acid, arsenic, ethanol
Charcoal is most effective if given in what time frame?
30-60min of ingestion (min use w/in 3hr)
When is gastric lavage most effective?
W/in 20-60 min of ingestion
*not commonly used
Indications for gastric lavage?
Removal of toxins, massive OD, highly toxic ingestions
What does gastric lavage do?
Dilutes/removes corrosive liquids & empty stomach in prep for EGD
What is whole bowel irrigation?
PEG lyte at high flow rates (2L/hr) to force intestinal contents out by sheer volume until rectal effluent is clear
Indications for whole bowel irrigation?
Large ingestion of Fe, Li, other drugs poorly absorbed by charcoal, SR or EC tablets of valproic acid, theophylline, ASA, verapamil, diltiazem, or other dangerous drugs, FB or drug filled packets
C/I for full bowel irrigation?
Ileus or intestinal obstruction, obtunded, comatose, convulsing
Drugs that are recognized by DAU-8 (drugs of abuse urine)?
Amphetamines, Barbituates, Benzos, Cannabinoids, Cocaine, Methadone, Opiates/heroin, Propoxyphene
First detection/duration of amphetamines?
First: 4-6hr
Duration: 1-2d
First detection/duration of Barbituates?
First: 2-4hr
Duration: 1-3d
First detection/duration of Benzos?
First: 2-7hr
Duration: up to 21d
First detection/duration of Cannabinoids?
First: 1-3hr
Duration: up to 60d
First detection/duration of Cocaine?
First: 2-6hr
Duration: 1-3d
First detection/duration of Methadone?
First: 3-8hr
Duration: 1-3d
First detection/duration of Opiates/heroin?
First (opiate): 1-3hr
First (heroin): 2-6hr
Duration: 1-3d
First detection/duration of Propoxyphene?
First: 3-8hr
Duration: 1-3d
MC hospitalization for overdose is due to which drug?
APAP (acetaminophen)
MC cause of acute liver failure in US?
APAP (acetaminophen)
Survival rate for APAP OD?
100% if tx w/in 8hr
Consider accidental OD of APAP when?
if pt has significant pain and is attempting to self medicate
Pathophys of acetaminophen (Tylenol)?
Release of cytokines, nitrogen, oxygen radicals during metabolism initiates secondary inflammation response w/in hepatic parenchyma –> fulminant liver failure, often irreversible, clotting and renal dysfunction possible
Onset of Tylenol OD?
completely abs in 2 hrs, serum conc. peak w/in 4hr
Liver injury: 8-12hrs
Hepatic necrosis/failure: 3-5d
Sx of Tylenol OD?
Asx initial, then N/V, anorexia, RUQ pain, jaundice, encephalopathy/coma
Toxic dose of Tylenol?
Adults: 7.5-10g
Kids (1-6): 200mg/kg
Work-up for tylenol OD?
-4hr APAP level from time of most recent ingestion, severity of elevations related to dose
-elevated AST (w/in 24hr)
-elevated ALT, bili, PT, lactate, phosphate, Cr (w/in 24-72hr)
-elevated ammonia (w/in 72-96hr if not tx)
-if intentional eval for coingestants w/ DAU-8
Tx for tylenol OD?
Activated charcoal 1g/kg (or 50g) w/in 4hr
-N-acetylcysteine (NAC) if level meets/exceeds lower line: PO 140mg/kg or IV 150mg/kg then x2d
Indications for immediate NAC administration w/ tylenol OD?
> 8hr since ingestion, pregnancy, presenting w/ hepatic failure
Other substances of potential source for Salicylate (ASA) OD?
Bismuth subsalicylate (Pepto), Alza-seltzer, Aspercreme, Percodan
Pathophys of ASA OD?
Inc respiratory center sensitivity, damage hepatocytes, inhibits PLT organization/amino acid synthesis
Onset of ASA OD?
Variable (dosage, route)
Effects of ASA OD?
Tinnitus/hearing loss, N/V, fever, lethargy, diaphoresis, epigastric pain, agitation, dec awareness, seizures or coma
What is Reyes Syndrome?
Hepatic failure w/ encephalopathy
*assoc w/ tx of peds viral illness w/ ASA
*30% mortality
Work-up for Salicylate (ASA) OD?
-Salicylate levels q4hrs after ingestion then q3hrs until levels decline
-ABG (metabolic acidosis)
-CBC, CMP, US, DAU-8, acetaminophen level, ETOH
Tx for Salicylate (ASA) OD?
Activated charcoal 50g adults, 1g/kg kids
-Urinary alkalization to pH 7.5-8 (prevent renal diffusion reuptake): mix 5% dextrose in water D5W plus 3 ampules of sodium bicarb
*infuse at rate for urine output 2-3mL/kg/hr
*complications: hypokalemia, hypocalcemia
-dialysis if severe toxicity
Prognosis of ASA OD?
Depends on serum level 6hr post ingestion
<35mg/L: no sx
35-70: moderate sx
70-100: severe
>120: potentially fatal
Most common meds with anticholinergic activity?
-Tricyclics (amitripyline/Elavil, imipramine/Tofranil, Paxil, Pamelor)
-Antihistamines (Benadryl, Atarax)
-Antispasmodics (ditropan, bentyl)
-Antiparkinsons (Cogentin)
-Antiemetics (Compazine, Phenergan)
-Antipsychots (Zyprexa, Seroquel, Clozaril)
-Muscle Relaxers (Soma, Flexeril, Robaxin)
Who accounts for half of all exposures of anticholinergic OD?
Children <6
Pathophys of anticholinergic OD?
Block muscarinic & nicotinic R’s
CNS blockage —> excitation/agitation
Central blockage —> hypermetabolic states
peripheral —> reduces sweat gland function
Onset of anticholinergic OD?
Most 1-2hrs
*excluding long acting
Duration of anticholinergic OD?
Mild resolves w/in 6hr
Severe or long acting: 1-2d
Effects of anticholinergic OD?
Red as a beet (flush), Dry as a bone (dry skin/membranes), Blind as a bat (mydriasis w/ loss of accommodation), Mad as a hatter (AMS), Hot as a hare (fever), Full as a flask (urinary retention)
Other: widened QRS, tachycardia, hypoactive bowel, HTN, tremor, myoclonic jerk/seizures, ataxia
TX for anticholinergic OD?
Activated charcoal 1g/kg kids, 50g adults
-Sodium bicarb for prolonged QRS
-Benzodiazepines for agitation/seizure
-Physostigime 0.5-2mg IV for both peripheral and moderate central anticholinergic toxicity
*avoid if purely tricyclic OD secondary to possible asystole
Those at disposition for anticholinergic OD should be what?
Observe for mild sx, admit if severe
Cause of serotonin syndrome?
Use of MAOIs w/in 5 wks of d/c fluoxetine, use of serotonergic agents w/in 2wks of d/c SSRIs
Common OD SSRI meds with serotonin syndrome?
Sertraline, Fluoxetine, Paroextine, Citalopram, Escitalopram, fluvoxamine
Common OD SNRI meds with serotonin syndrome?
Duloxetine, Venlafaxine
Common OD MAOI meds with serotonin syndrome?
Phenelzine, Moclobemide, clorgyline, isocarboxazid, selegiline
Common OD Tricyclic antidepressant meds with serotonin syndrome?
Amitriptyline, Nortriptyline
Common OD (other) antidepressant meds with serotonin syndrome?
Trazadone, Nefazodone, Clomipramine, Triptans
Common OD herbal supplements with serotonin syndrome?
Ginseng, St. John’s Wort
Common OD meds of abuse with serotonin syndrome?
Amphetamines, ecstacy, LSD, cocaine
Common OD miscellaneous meds with serotonin syndrome?
Dextromethorphan (cough med)
Neuron phys/pathophys with serotonin syndrome?
Pathophys of serotonin syndrome?
Meds cause inc serotonin production and uptake, as well as postsynaptic hypersensitivity
Onset of serotonin syndrome?
50% w/in 2hr, 75% w/in 24 hrs
Effects of serotonin syndrome?
-Mental status change: agitation, confusion, hypomania, delirium
-Autonomic instability: shiver, diaphoresis, midriasis, tachycardia, HTN, hyperthermia (104deg), hyperactive bowels
-Neuromuscular hyperactivity: hyperreflexia, tremor, clonus
Work-up for serotonin syndrome?
Hx and PE, hx of serotonergic agent used w/in past 5 wks and exam w/ hypertonia, temp > 100.4, clonus
Tx for serotonin syndrome?
D/c med (70% resolve in 24hr)
-Supportive: cooling, IV fluids
-Charcoal
-Benzos
-Cyproheptadine (antihistamine) PO or Chlorpromazine IV
-25% require intubation
Ddx for serotonin syndrome?
Alcohol withdrawal, sympathomimetic abuse, meningitis/encephalitis, toxidromes
Tx of BB OD?
Glucagon 1-2mg IV q5min prn
Tx of CCB OD?
IV calcium gluconate (up to 4g) or IV calcium chloride (1g) and/or glucagon (5-10mg), +/- vasopressors
Pharmacology of ETOH?
90% absorbed by 60min –> metabolized in liver at 20mg/dL/hr—> CNS depression via desensitized GABA and NMDA R’s
Consequences of ETOH?
Inc. risk for esophageal, gastric, liver malignancy, gastritis, malnutrition, hepatosteatosis, hepatitis, fibrosis, inc. risk for HCV infection
What is alcohol abuse?
Continued drinking despite adverse consequences, having alcohol related legal/social problems
What is alcohol dependence (alcoholism)?
Physical cravings, withdrawal sx, need for more ETOH for intoxication
What is alcohol withdrawal?
Physical sx a pt who has developed dependency experiences upon abrupt cessation
Hx for ETOH?
-Type, amount
-Drinking pattern, frequency of >5 drinks/occasion
-Other drugs
-Complications of use, withdrawal sx
-CAGE tool
What is the CAGE screening tool for ETOH?
Cut doen
Annoyed
Guilty
Eye-opener
(questions)
1 pt for each yes, 2+ concerning for abuse
Effects of acute mild-mod intoxication of ETOH?
Loss of behavior inhibition, CNS depression, vasodilation (hypothermia, hypotension), tachycardia, resp. depression, diminished gag reflex, hypoglycemia, loss of fine motor
Effects of acute severe intoxication (poisoning) of ETOH?
Loss of gross muscle control (ataxia, slurred speech), nystagmus, acute pancreatitis or gastritis, severe myocardial depression, lactic acidosis, pulm edema, loss of gag, arrhythmia/cardio collapse/sudden death
Tx of acute alcohol intoxication?
-Assess ABCDE’s (and gag), sit upright if diminsished
-assess for secondary injury/aspiration
-Consider other drugs
-depression?
-Antiemetic: Zofran *least sedating
-Observe until clinically sober w/ stable VS and responsible adult
-IV fluids, dec time to sobriety
ETOH withdrawal sx?
-Autonomic hyperactivity: tachycardia, HTN
Tx for alcohol withdrawal?
Management of alcohol withdrawal tx based on disposition?
What is ethylene glycol?
What is methanol?
What is diethylene glycol?
What is propylene glycol?
What is isopropanol (isopropyl)?
Tx for ethylene glycol ingestion?
Tx for Propylene glycol ingestion?
Tx for Isopropanol ingestion?
Meds for memory???
