Tox Flashcards
dosing of opiod overdose
naloxone (narcan)
starit with 0.04mg for adults and 0.1mg/kg kids
if no increase in RR in 2-3min –> increased to 0.5mg –> 2mg –> 4mg –> 10mg –> 15mg
management of sympathomimetic overdoses
benzos 1st line
antipsychotics if pts still agitated
difference betweeen sympathomimetic toxidrome vs antimuscarinic
sympathomimetics has sweating
antimuscarinic has dry mucosal membranes
sources of antimuscarininc toxidromes
Quetiapine, TCAs carbamazepine, jimson weed, oxybutinin, diphenhydramine
clinical features of antimuscarinic toxidrome
(mad hatter, dry as a bone, etc...) AMS mydriasis urinary retention ileus tachy anhidrosis (dry) mumbling speech
antidotal therapy for antimuscarinic toxidrom
physostigmine (mod-sev) 0.5-2mg IV (not to exceed 1mg/min)
tx: agitation (benzo)
wide complex tachy (Na bicarb)
cool blankets, IVF
contraindications to physostigmine
bradycardia av block severe asthma allergy to it or salicylate mechanical obstruction GU orGI
muscarinic toxidrome
pilocarpine, mushrooms, organophosphates
DUMBELLS (diarrhea, urination, miosis, brady, bornchorrhea, emesis, lacrimation, sweating
tx of muscarinic toxidrome
atropine given until bronchorrhea resolves
start 0.5-2mg Q5min
pralidoxime
sedative overdose management
supportive care
Flumazenil for benzo toxicity
phenobarb elimination enhance with urinar alk (Na bicarb infusion) and/or hemodialysis
which syndrome has lead pipe rigidity
NMS
vs
Serotonin syndrome has hyperreflexitivity
presentation of serotnonin syndrome
clonus hyperreflexia lower extremity rigidity diarrhea shivering tremor diaphoresis
tx of serotonin syndrome
benzos 1st line
cyproheptadine in refractory cases
dantrolene for rigidity
NMS
90% in 1st week of new med
AMS, hyperthermia, tachy, lead pipe rigidity, bradykinesia, rhabdo
tx of NMS
benzos
bromocriptine in refractor cases
dantrolene for rigidity
indications for emergency dialysis
acidosis electrolytes intoxications overload uremia
dialyzable drugs
salicyclates
toxic alcohols
lithium
INH
metformin
theophylline
atenolol
topiramate
acyclovir
phenorbabital
Common indications for charcoal
cyanide cyclic antidepressants CCBs colchicine mushrooms cocaine aspirin
contraindications to using charcoal
iron
lithium
arsenic
methanol
ethanol
ethylene glycol
strong acids or bases
almond odor
cyanide poisoning - burning nitrites, pesticides, nitroprusside
carrot smells
water hemlock - cicutoxin water vegetation
garlic breath
organophosphates
arsenic
selenium
mothballs scent
camphor - topical pain cream
naphthalene - insecticide
wintegreen
methyl salicylate
rotten egg scent
sulfur dioxide
hydroge sulfide
mc toxin ingested in US
acetaminophen
when does acetaminophen toxicity develop in an acute single ingestion
> 150mg/kg
up to 200mg/kg in kids <8yrs old
levels obtained prior to 4hrs
<100mcg/ml between 2-4hrs = (-) 100%
<100cg/ml between 1-2hrs = (-) 97%
> 300mcg/ml at any time = tx needed
NAC
72hr course if PO
21hr if IV
presentation of salicylates overdose
- tachy
- resp alk due to tachpnea
- n/v/gastritis
- met acid
- ketoacidosis
management of salicylate overdose
- IVF w/ LR
- urinary alkalinization is key
- Goal serum pH 7.45-7.55 with urine pH >7.5
how to achieve urinary alkalinization
bolus na bicar 1-2mEq/kg prn target pH followed by infusion
how to prepare nabicarb infusion
add 3ampules of na bicarb and 40mEq K+Cl to 1L of D5W
infuse at 150-250ml/hr
hemodialysis indications for salicylate overdose
- renal failure
- worsening acidosis or rising levels despite aggressive tx
- AMS
- level >100mg/dL
end organ toxicity of acute salicylate toxicity <150mg/kg (mild)
tinnitus
hearing loss
dizziness
n/v
end organ toxicity of acute salicylate toxicity 150-300mg/kg (mod)
tachypnea hyperpyrexia diaphoresis ataxia anxiety
end organ toxicity of acute salicylate toxicity >300mg/kg (severe)
AMS seizures acute lung injury renal failure cardiac arrhythmias shock
clinical features of NSAIDs overdose
>400mg/kg gastritis met acidosis ams tachy seziures AKI
tx of NSAID overdose
supportive
LR>NS
sucralfate for gastritis
opiod overdoses associated with seizures
tramadol
propoxyphene
meperidine
opiods associated with cardiotoxicity including QT prolongation
methadone**
loperamide
propxyphene
amides vs esters
amids = lidocaine, bupivacine, prilocaine
esters = tetracaine, benzocaine, cocaine
(amides = 2 i’s and esters = 1 i in their name)
toxic dose of lido w/ and w/o epi
with epi = 7mg/kg, 1% 10mg/ml, 2% 20mg/ml, max 500mg
w/o epi = 5mg/kg, max 300mg 1% 10mg/ml, 2% 20mg/ml
toxic dose of bupivicaine w/ and w/o epi
w/ epi = 3-5mg/kg (max 225)
0.5% sol = 5mg/ml
w/o epi = 1.5-3mg/kg (max 175mg)
management of QRS widening
boluses of sodium bicar 1-2mEq/kg q5min
until QRS interval responds or pH ?7.55
management of QT prolongation
mag sulfate 50mg/kg x1 empirically
K needs to be >4.5
causes of methemoglobinemia
benzocaine, dapsone, nitrites, metoclpraide
nitrobenzne, aniline dyes, trinitrotoluene
chocolate blood on venipuncture think
methomglobinemia
measure via co-oximetry to confirm dx
tx - methylene blue 1-2mg/kg reduces Methb to hemoglobin (renders pulse ox meaningless for a few min
when is methylene blue contraindicated
G6pd def
if methylene blue is unavailable treat with blood transfusion
acute toxicity of warfarin can lead to
- elevated INR above range
- calciphylaxis in pts w/ ESRD leading to thrombi formation
- skin necrosis within first 10 days typically in obese middle aged women w/ protein C def
tx of warfarin toxicity
INR <5 w/ no sig bleed = hold next dose or lower daily dose
INR 5-9 w/ no sig bleed = hold next 1-2 doses and consider vit K
INR >9 w/ no sig bleed = hold coumadin and give vit K
Serious bleed at any INR = hold coumadin give vit K and FFP or»_space; PCC (better)
reversal agent for dabigatran
idarucizamab and also hemodiaysis can help eliminate dabigatran
alteplase reversal agent
amiocproic acid
enoxaprin and unfractionated heparin reversal agent
protamine sulfate
toxicity signs for CCBs
bradycardia hyperglycemia ileus bowel infarction hypotension
management of CCBs toxicity
IVF
Ca gluconate 1-2g IV
NE and EPi
high dose insuline(esp for verapamil and dilt)
bolus insulin 1unit/kg and then start infusion 1u/lg/hr
Beta blocker toxicity presentation
bradycardia
hypotension
QRS widening and/or QT prolongation (propanol, sotalol)
hypoglycemia, seizures
tx of beta blocker toxicity
glucagon traditionally (ADR n/v)
now IVF, and manage hypotension with pressors
Na bicarb for QRS >120ms, 1-2 mEq/kg q5min until its narrowed or pH >7.55
clonidine toxicity presentation
CNS depression
hypotension
bradicardia
MIosis
seizures, hypothermia (less common)
management of clonidine toxicity
supportive
IVF for BP
naloxone for CNS depression (may need high doses)
Digoxin toxicity presentation
bradydysrhythmias (acute)
tachydysrhythmias (chronic)
Hyper K >5 (50% mortality if no tx), >5.5 (100% mortality if no tx)
Visual disturbances (perceived flashes of light, abnormal colored vision)
Gi symptoms, weakness
Digoxin toxicity EKG
bidirectional v tach and paroxysmal atrial tachy with block
scooped/scagging ST segment (salvador dali mustache)
tx of digoxin toxicity
supportive digoxin Fab fragments if: K >5 dig level >15 any time dig level >10 ( >5hrs post ingest) progressive bradydysrhthmias severe ventricular dysrhythmias ingestion >4mg kid ingestion >10 adult
what can falsely elevated dig levels
digoxin Fab so once given dig levels dont mean anything but a free digoxin concentration can be used if available
classes of antidysrhythmics
Simply Block the Proper Channel
I = Sodium II = beta adrenergic III = Potassium IV = Calcium
chronic amiodarone toxicity may include
thyroid dysfunction
pneumonitis
corneal microdeposits
skin discoloration
ACE inhibitors ADR and notes
hyperkalemia
hypotension
cough
angioedema
transient Cr bump
monitor in pts with renal issues
Losartan (angiotensin II receptor blocker) ADR and notes
hyperkalemia
hypotension
cough
monitor in renal pts
loop diuretics ADR and notes
ototoxicity (high doses)
hypokalemia
hypomag
monitor electrolytes and orthostatics
thiazide diuretics ADR and notes
hypokalemia
hypo Na
volume depletion
monitor electrolytes and orthostatics
spironolactone (K sparing) ADR and notes
hyper K
gynecomastia
amiodarone ADR and notes
QT prolongation
hepatotoxicity
pulm fibrosis
thyroid toxicity
Hypotension w/ rapid infusion
diltiazem and verapamil (nondihydropyridine CCB) ADR and notes
hypotension
AV block (esp when combined with beta blockers)
bradycaria
CYP3A5 substrates
amlodipine (dihydropyridine CCB) ADR and notes
hypotension
edema
uses for metoprolol vs esmolol
metoprolol (Afib)
esmolol (short acting aortic dissection
what pts should you avoid using clopidogrel on
active bleeding
pts with stroke hx or TIA
heparin dose adjustments
not necessary in renal dysfunction
Ok during pregnancy
enoxaprin dose adjustments
dose reduction in renal dysfunction pts
Ok during pregnancy
presentation of phenobarbital toxicity
CNS depression
resp depression (occasionally)
hypotension
bradycardia
management of phenobarbital toxicity
supportive
urinary alkalinization (bicar bolus and infusion)
hemodialysis
phenytoin toxicity presentation
typically chronic due to zero order elimination
cerebellar signs (ataxia, nystagmus and dysmetria)
IV - cardiotoxic/seziures
elimination can be enhanced by hemodialysis
carbamazepine toxicity presentation
CNS depression
cerebellar signs
seizures, cardiotoxc (QRS widening and QT prolongation)
antimuscarininc toxicity
management of carbamazepine toxicity
cardiotoxic w/ Na bicarb and/or mag
seizures w/ benzos
physostigmine for antimuscarininc
consider hemodialysis for levels near 40mcg/ml
topiramate toxicity presentation
CNS depression
cerebellar signs
normal gap acidosis
hypo K
hyper Cl
seizures
management of topiramate toxicity
replace K w/ potassiu phosphate or K acetate
benzos for seizures
hemodialysis
valproic acid toxicity presentation
CNS depression QT prolongation elevated AST and ALT Pancreatitis Bone marrow suppression
hypotension
hyper ammonemia
less common seizures
management of valproic acid toxicity
if soon after overdose -> charcoal
- L carnitine indicated in AMS pts and w/ elevated levels
- -> dose 50-100mg/kg followed by 25-50mg/kg q6hrs until VPA level <100
naloxone for CNS dep
hemodialysis - >500mcg/ml
TCA toxicity
- QRS widening from Na channel poisoning
- QT prolongation due to K efflux blockade
tachy or brady (severe)
hypotension
sedation, antimuscarinic tox, seizures, serotonergic tox
management of TCA toxicity
QRS widening w/ Nabicarb 1-2mE1/kg q5min until QRS interval resolved or pH >7.55
management of refractory hypotension w/ TCA toxicity
NE or Epi
Dopamine is contraindicated (can exacerbate hypotension)
SSRI toxicity
tachycardia
GI symptoms (mc)
CNS depression
QRS widening and/or QT prolongation (citalopram)
hyperreflexia
bupropion toxicity
can take >24hrs
seizures
tachy, CNS depression
QRS wid and/or QT pro
management of bupropion toxicity
Gi decontamination with single dose activated charcoal or whole bowel irrigation
lithium toxicity
GI signs predominate
Neuro signs
serum level correlates w/toxicity
management of lithium toxicity
whole bowel irrigation
aggressive fluid resuscitation w/ NS
hemodialysis if concomitant renal insufficiency
normal lithum level
0.6-1.2
ADR of clozapine
agranulocytosis
weight gain
hyperglycemia
myopathy
EKG finding of atypical antipyschotics
QT prolongation (although rare)
ADHD stimulant toxicity
tachy, HTN, diaphoresis
mydriasis, agitation
seizures
tx - supportive, benzos for szs
sulfonylureas toxicity and management
hypoglycemia >12hrs later
GI decontamination
supp dextrose + octreotide - preferred antidote (safer than glucagon) dose = 1mcg/kg IV/SQ 16hrs prn
metformin toxicity and management
sig lactic acidosis in pts w/ risk factors: ckd or chronic liver dz
tx - supp hemodialysis if: rising lactate levels, renal insuff w/ hyper K
ondansetron (zofran) ADR
qt prolongation at doses >32mg
prochlorperazine ADR
sedation
antimuscarinic toxicity
miosis, rhabdo
cardiotoxicity
management of prochlorperazine
tx cardiac and antimuscarinic tox as usual
lipid emulsion in massive overdose
metoclopramide toxicity
CNS depression
QT prolongation
methemoglobinemia
extrapyramidal signs
tx like the rest
what is the risk of allergic rxn to 1st and 2nd gen cephalosporins in PCN allergic pts
1% and the risk for 3rd and 4th gen cephalosporins = negligible
fluoroquinolones ADR
QT prolongation
associated with tendinopathy (esp in elders)
macrolides (azithro) ADR
QT prolongation
large doses cause sensorineural hearing loss
CYP 4500 3A4 inhibition
chronic use = hepatitis
tetracyclines (doxy) ADR
pill esophagitis
photosensitivity
occasionally nephrotoxic
hepatotoxic
ADR of vanc
red man syndrome
INH toxicity
CNS depression
seizures
metabolic acidosis
hepatitis
antidote for INH
pyridoxine dose should be equivalent to ingested
Antimalaria toxicity
GI symptoms, tinnitus
CNS depression, seizures,
dysrhythmias, rnela fialure
QRS wide, QT prol, hypotension
acyclovir toxicity
AMS
seizures
nephrotoxicity
nucleoside reverse transcriptase inhibitors ADR
lactic acidemia
zidovudine - hematologic toxicity
pancreatitis
dextromthorpan ADR
dissociation
large ingestion -> serotonin toxicity - AMS, tachy, hyperthermia, clonus, hyperreflexia, diarrhea
management of dextromethorphan toxicity
supp care
benzos
cyproheptadine
dantrolene for rigidity
antihistamine toxicity
sedation, (antimuscarinic) AMS, tachy
anhidrosis, mydriasis
ileus, urine retention
rhabdo and cardiotoxicity
management of anthistamine toxicity
cardio tox like usual
szs w/ benzos
antimuscarinic w/ physostigmine
consider lipid emulsion in massive overdose
signs of alcohol withdrawal
tremor, restlessness
hallucinations (visual>auditory)
seizures
DTs (48-96hrs)
management of alcohol withdrawal
diazepam and chlordiazepoxide (long acting)
benzos (ineffective in malnourished pts) and failure mcc underdosing
methanol toxicity (wiper fluid, carburetor cleaner, etc)
mild inebriation
elevated methanol level
wide gap acidosis
ocular signs -> lesions in putamen
hyperglycemia and pancreatitis (less common)
ethylene glycol toxicity (antifreeze)
mild-mod inebriation
wide gap acidosis
AKI w/ hypo Ca
CN palsies (less common)
management of ethylene glycol toxicity
if early - fomepizole is sufficient
if late - hemodialysis
isopropyl alcohol toxicity (rubbing alcohol)
significant inebriation
gastritis
ketosis but NO acidosis
Hypotension
CNS depression
chronic stimulant use is associated with
vasculitis
cardiomyopathy
pulm HTN
valvular injury
when should flumazenil be avoided
in pts who have ingested a proconvulsant xenobiotic aka: TCA, tramdol or buprpion
how can phenobarbital elimination be enhanced
hemodialysis and urinary alkalinization
carbon monoxide toxicity
greater affinity for Ox than Hgb (pulse ox - false nml)
“flu w/o the fevere”
HA, N, confusion
dyspnea, chest discomfort
rhabdo
dysrhthmias, MI, Sz, Coma,
dx and tx of CO toxicity
measuring COHb via co-oximetry
tx - 100% oxygen reduces half life of COHb
CN toxicity
rapid unconsciousness
seizures
acidosis
cardio tox
arterialization (bright red blood)
tx of CN toxicity
supp care
antidotal therapy with amyl nitrite and sodium nitrite (avoid in smoke inhalation)
sodium thiosulfate IV
hydroxocobalamin IV (HTN and skin discoloration are temporary ADR)
hydrogen sulfur toxicity (flammable colorless gas)
smells like rotten eggs but high levels olfactory paralysis
irritation of skin and mucus membranes
ha, vomiting, szs, coma
cardiovascular instability
tx of hydrogen sulfur toxicity
supp
nitrites (weak evidence)
insecticide toxicity
DUMBELS defecation urination miosis bradycardia bronchospasm bronchorrhea emesis lacrimation salivation
iron toxicity
sign toxic >60mg/kg GI phase (first 6hrs) - vomiting and/or diarrhea Latent phase - look better but developing tox at cellular level Shock + Acidosis phase
management of iron toxicity
consider whole bowel irrigation
deferoxamine indicated for pts with signs and symptoms + serum level >450mcg/dL
- dose 15mg/kg until iron level therapeutic or sym resolved
- ADR hypotension give Fluids and may predispose pts to yersinia infections
lead toxicity
abd pain, anemia, acute liver injury, encephalopathy
chronic - anorexia, weight loss, constipation, HTN, anemia, nephrotoxic, CNS issues
dx and tx of lead toxicity
dx - whole blood lead level
tx - supp, chelation therapy if indicated, dimercaprol, CaEDTA, and succimer
whole bowel irrigation (for large acute ingestion)
arsenic toxicity
gastroenteritis that may be hemorrhagic
hypotension, tachycardia
metabolic acidosis, AMS, rhab
neuropathy, pancytopenia
chronic: BMS, peripheral neuropathy, pvd, portal HTN, skin disorders
common skin finding for arsenic poisoning
spots of hyperkeratosis and hyperpigmentation on the palms and soles seen in chronic arsenic poisoning
dx and tx of arsenic toxicity
dx - 24hr urine arsenic levle
tx - supp, chelation therapy if indicated w/ dimercaprol, unithiol, succimer
whole bowel irrigation (large acute ingestions)
hydrofluoric acid toxicity
rust remover, glass etching supplies
local mucus membrane irritation
bronchospasm
corneal injuries
hypo Ca, Mg
hyper K
QT prolongation
management of hydrofluoric acid toxicity
decontamination, supp supplemental Ca - topical Ca for burns or Ca gluconate 10% solution 0.2-0.4mL/kg IV for systemic toxicity
caustic toxicity (toilet bowel cleaner, bleaches, car batteries, gun bluing agents)
alkalis cause liquefactive necrosis
acids cause coagulative necrosis
mucus membrane and skin irritation, pneumonitis
management of caustic injuries
DONT INDUCE EMESIS
endo for pts w/ resp distr, hematemesis, stridor, vomiting, drooling
GI decontamination except for zinc Cl and cationic detergents
hydrocarbon toxicity (essential oils, gas, lighter fluids, solvents)
bronchospasm, pneumonitis
(avoid albuterol see below)
skin damage, GI injury, CNS effects (lead to leukoencephalopathy)
Sensitize myocardium
antimuscarinic plants
jimson weed
atropa belladonna
nicotinic plants
poison hemlock
tobacco
mydriasis, tachy, weakness, HTN, szs, sweating
water hemlock
causes status epilepticus by antagonizing GABA receptors
may require high doses of benzos
castor bean toxicity
disrupts protein synthesis inhibiting 28S subunit of the ribosome producing significant GI symptoms and multi organ failure
tx - spp care, fluid resus
death cap mushroom (amanita phalloides)
cause of 95% mushroom deaths
stage 1 - GI phase (6-12hrs)
stage 2- liver damage, elevated transaminases and bili, coagulopathy, hepatic encephalopathy (2-3days)
stage 3- liver and renal failure (death in 3-7days)
management of death cap mushroom toxicity
activated charcoal if presentation is 1-2hrs
spp care with fluid and electrolyte resus
NAC (IV)
PCN (high dose IV)
OTC raw milk
stone fish
dyspnea, spasticity
hypotension, tachycardia
vomiting, abd cramping
tx - spp care, local wound care, HOT water immersion (45C) 30-60min and anti-venom
stingrays envenomation presentation
sig pain and concomitant trauma
vomiting, syncope
seizure, hypotension
heart failure
tx of stingray envenomation or injury
spp care, local wound care
HOT water immersion (30-60min)
infection in 13% of cases so prophylactic abx should be given
cnidaria (jelly fish, portuguese man o war, anemones)
presentation
pain, papular lesions
local tissue injury
vomiting seizures
hypotension
cardiovascular collapse
death
management of cnidaria injury
spp care
inactive nematocyts w/ vinegar for 30 min (**except for American Sea nettle, mauve stinger and lions mane jellyfish)
control pain w/ parenteral narcotics and hot water immersion 45C (30-60min)
scombroid presentation
develops when histidine gets decomposed by bacteria to histamine
causing flushing and gastroenteritis (within min)
fish that are associated with scombroid
TUNA
mackerel
mahi mahi
albacore, bonito, skipjack, blue fish
management of scombroid poisoning
H1 and H2 antagonists
albuterol and occasionally epi for the tx of bronchospasm
Ciguatera toxin fish species
GROUPER
sea bass
barracuda
parrot fish
sturgeon
presentation of ciguatera toxin following large consumption
2-6hrs later:
temperature reversal
HA, diaphoresis
brady hypotension
vomiting, abd cram, profuse diarrhea
sensation of loose teeth
management of ciguatera toxin
spp care
gabapentin
tetrodotoxin (TTX)
species
pathyophys
tx
blue ringed octopus
pufferfish
TTX blocks Na channels -> paresthesia, weakness, dysphagia, hypotension, brady and
flaccid paralysis (6-24hrs)
tx - spp care, neostigmine (possibly)