Tox Flashcards
1
Q
Antitodes to Acetampinophen
A
- NAC: 150mg/kg IV then 15mg/kg/hr x23 hours (or 140mg/kg po load)
- Fomepizole: if cross product >10,000 - - give 15mg/kg (blocks cytochrome 2E1)
Vit K
2
Q
Viperidae
A
Copperhead, rattlesnakes, cotton mouths
- most often local tissue effects and coagulopathy
- crofab indicated with swelling crossing joints, coagulopathy, etc
3
Q
Elapidae
A
coral and mamba snakes
- neurotoxic
- antivenom early
- red on yellow
4
Q
source, results, and treatment of hydrofluoric acid exposure
A
- ruse removers, cleaners, insecticides
- hypocalcemia, hypomag, hyperK
- local tissue necrosis
- decon and calcium GLUCONATE (not chloride) near injury
5
Q
Antitodes to Acetampinophen
A
- NAC: 150mg/kg IV then 15mg/kg/hr x23 hours (or 140mg/kg po load)
- Fomepizole: if cross product >10,000 - - give 15mg/kg (blocks cytochrome 2E1)
Vit K
6
Q
5 treatments for CCB and BB overdose
A
- charcoal
- atropine
- Calcium (CCB)
- glucagon
- high dose insulin (ccb>bb)
7
Q
high dose insulin
A
- CCB>BB overdose
- theoretically increases myocyte metabolism
- 1 unit/kg reg bolus then 1 unit/kg/hr
8
Q
what enzyme is ccb metabolized by
A
cyp3A4
9
Q
difference between CCB and BB overdose
A
CCB: hyperglycemia
BB: in peds may cause hypoglycemia
10
Q
which beta blockers cause EKG changesm (4)
A
Propranolol- Na channel blockade, QRS
Sotalol - K blockade, QT prolonged
Carvedilol and acebutalol- Na channel blockade
11
Q
why is propranolol uniqe
A
Na channel blockade
lipophilic -> crosses blood brain barrier and can cause seizures
12
Q
Anti-arrhythmic Drug class
A
I: Na channel blocker
II: beta blocer
III: K channel blockade - prolongs APD
IV: CCB
13
Q
Bupropion overdose
A
- QRS and QT prolongation due to gap junction inhibition
- seizures
14
Q
Palytoxin
- where, mechanism, exposure
A
- produced by algae
- binds Na/K ATPase pump and locks it open
- dermal: irritation, pain, edema, erythema
inhalation: parasthesia, dysguesia, HTN, respiratory depression and coma
15
Q
becaquerel
sievert
gray
A
- Becquerel: amount of radiation from decayed matter
- Sievert: equivalent absorbed radiation dose adjusted by area of body exposed
- Gray = absorbed energy (J)/mass of part receiving radiation (kg)
16
Q
radiation injury labs
A
- trend ALC - predicts mortality
17
Q
type of radiation
A
- Alpha (particles): 1-2 cm, does not penetrate skin; highly ionizing, very dangerous to DNA if ingested or injected
- Beta (particles): penetrates a few layers of skin
- gamma and xrays (photon): passes all layers of skin; gamma rays tx cancer
18
Q
metabolic and laboratory changes with aspirin
A
EARLY respiratory alkalosis
metabolic acidosis- lactate and ketones
- hypokalemia
- hypoglycemia (very early hyperglycemia)
- falsely elevated chloride
- elevated INR
19
Q
aspirin units (therapeutic, overdose)
A
mg/dcl
15-3o mg/dcl is therapeutic
20
Q
early to late manifestations of aspirin toxicity
A
Early: GI/N/V and initius
progressing: tachypnea, fever
late: coagulopathy, cerebral edema and seizures
21
Q
aspirin treatment (A-G and K)
A
A: alkilinization- BICARB: goal urine pH 8: a few amps bicarb and then 3 amps in 1L with 40 KCl
B: breathing is fast, avoid intubation
C: charcoal - bezoars possible
D: dialysis
E: electrolytes: K >4
F: frequent labs
G: hypglycemia
K: Vit K if INR >2
22
Q
indications for HD 2/2 aspirin
A
level nearing 100
level nearing 40 and pregnant
fluid restrictions - kidney, heart
AMS or seizure
therapies failing
23
Q
Two tox exposures that are bad news for pregnancy
A
- aspirin: fetus more acidic environment
- CO: like fetal hemoglobin
24
Q
Sulfonylurea toxicity management
A
- blocks K channels in pancreas -> insulin release regardless of BG
- ends in “ide” - glipizide, glimeperide
- one pill can kill peds
OCTREOTIDE 50-100mg SC
25
Cyclobenzarpine MOA and overdose
- NE and serotonin reuptake inhibition, centrally
- more sedating
- long half life 18h-33h
- ANTICHOLINERGIC effects
- NA channel blockade
26
Anticholinergic toxidrome
mad, blind, red, hot, dry
benadryl
27
cholinergic toxicity
dumbells- diarrhea, urination, miosis, bradycardia, emesis, lacrimation, lethargy, salivation
pesticides
28
acute and chronic lithium OD
acute: N/V
chronic: CNS -> rigidity, tremor, ataxia, slurred speech
29
Lithium therapeutic range
0.5 mEq/L - 1.5 mEq/L
30
Lithium toxic range and risk factors
> 1.5 (dialyze at 4)
- volume depletion (causes renal retention - renally excreted)
- CHF, CKD, ACEi/ARB or other diuretics
- age >60
31
Lithium toxicity management
- NACL (kidneys confuse Li and Na - giving NaCl helps prevent lithium retention
- agressive fluids
- discontinue ace/arb/diuretics
- HD at Li > 4mEq/L
32
what class of drugs is not dialyzable
antipsychotics
33
antipsychotic pyramidal side effects and management
- acute dystonia: benztropine, benadryl
- Akasthesia: B-CALM
B blocker, Clonazepam, Anticholinergic, cLonidine, Mirtazapine (5HT2A block)
- Tardive dyskinesia: VMAT2 inhibitors
34
Clozapine, quetiapine (Seroquel), palperidone (invega) or aripiprazole?
granulocytopenia, sialorrhea, seizures (dose related), EKG changes
clozapine
35
Clozapine, quetiapine (Seroquel), palperidone (invega) or aripiprazole?
abuse causes euphoria with possible withdrawal, structurally simailar to TCA, bezoar formation
quetiapine
36
Clozapine, quetiapine (Seroquel), palperidone (invega) or aripiprazole?
metabolite of resperidone
prolonged tachycardia
required 24 hour obs
palperidone
37
Clozapine, quetiapine (Seroquel), palperidone (invega) or aripiprazole?
effects on dopamine, serotonin, H1 and a1 adrenergic receptor; odd presentation of biphasic light somnolence, dystonia, orthostatic hypotension, anticholinergic toxidrome; tx= supportive care; 10h obs in OD
aripiprazole
38
Diphenhydramine MOA
H1 blocker
- lipophilic: crosses BBB
At high doses - Na and K blockade -> QRS and QT prolongation
39
fatal dose of diphenhydramine
20-40mg/kg
40
diphenhydramine effects
antimuscarinic effects, it can produce blurred vision, dry mouth, urinary retention, tachycardia, nausea, and constipation. EKG changes can occur including widening of QRS from sodium channel blockade and tachycardia.
41
diphenhydramine treatment
- bicarb for EKg changes
- foley placement and temp management
- benzos for seizures
- physostigmine for delirium
42
physostigmine in benadryl OD
- Reversible ACh-ase inhibitor that crosses BBB; onset 3-8 min, works for 30-90 min
- Contraindications: bradydysrhythmias, AV block, TCA/Na blocker toxicity, seizures, asthma or bronchospasms
- 2 g over 5 min IV
43
metformin toxicity
GI symptoms → lethargy → seizure and CV collapse → coma
44
metformin OD management
- causes lactic acidosis via inhibition of gluconeogenesis and mitochondrial complex
charcoal
bicarb
HD (decreased mortality if dialysis <6 hrs)
45
osmolar gap formula
2Na + (BUN/2.8) + (glucose / 18) + (EtOH / 4.6)
46
Toxic alcohol management, indications, dosing (4)
Fomepizole
Osm Gap / HAGMA with toxic alcohol >20 or high suspicion
15 mg / kg followed by 10 mg/kg q12h
NaHCO3 (most useful in methanol)
Folic acid (methanol)
Thiamine (B1) and pyridoxine (B6) and Mg (ethylene glycol)
HD: definitive
47
windshield wiper fluid
methanol
48
methanol toxic metabolite
formic acid
49
methanol presentation
mild intoxication with long slow elimination
HAGMA
snowfield vision
basal ganglia toxicity / parkinsonism
50
ethylene glycol toxic metabolites
Glycolic acid
oxalic acid
51
antifreeze
ethylene glycol
propylene glycol
52
ethylene glycol presentation
Antifreeze
intoxication with more rapid (RENAL) elimination
- nephrotoxicity
- urine fluorescence
- lactate gap (False VBG lactate)
53
wallpaper or paint stripper
diethylene glycol - similar to ethylene glycol just two molecules
54
isopropyl alcohol toxic metabolite
acetone
55
rubbing alcohol
isopropyl alcohol
56
isopropyl alcohol presentation
ketosis without acidosis
significant inebriation with AMS, resp depression, obtunded
57
propylene glycol toxic metabolite
lactate
58
methanol vs ethylene glycol vs isopropyl alcohol
methanol: windshield wiper fluid, AGMA, mild and prolonged intoxication, snowfield vision
ethylene glycol: antifreeze, AGMA, quicker and renally elimination intoxication
isopropyl alcohol: rubbing alcohol, ketosis without acidosis, obtundation
59
absinthe made from and contains?
wormwood
contains thujone
60
what determines where in respiratory tract will be irritated by irritant gas?
water solubility
high: eyes and mucus membranes
low solubility: lower airway
61
management for irritant gas exposure
1. remove source
2. humidified O2 or PEEP if hypoxic
3. HCO3 of chlorine expected
4 can consider nebs or cxr
62
which irritant gas has special management
chlorine gas- nebulized bicarb
63
difference between irritant gas and asphyxiants
irritant gases irritate
asphyxiants prevent O2 absorption or distribution (CO and CN)
64
when to expect CO
smoke inhalation, summer or winter with generators, family members
- ZAMBONI or METHYLENE chloride
65
3 mechanisms of CO
1. hgb shift to left
2. myoglobin binding- decreased cardiac contractility
3. displaces NO -> hypotension
66
diagnosis and treatment of CO
1. VBG with CO-ox which will give % carboxyhemoglobin
2. hyperbarics a discussion with >25% or 15 if pregnant
3. 100% FIO2 via NRB or HFNC x 4 hours for goal <3%
67
when to actually consider hyperbarics with CO
">25% or 15 if pregnant"
put on 100% for 4 hours
do cerebellar walk test
68
whats the benefit of hyperbaric with CO?
prevents delayed neurologic sequelae
69
sources of CN
Cyanide salts
B17/amydalin supplements
fruit seeds
fire- burning of furniture - hydrogen CN
70
MOA CN toxicity
sudden collapse in fire -> from burning of furniture
blocks cytochrome oxidase -> lactic acidosis
71
presentation of CN
SUDDEN collapse
fire victims
72
options for management of CN
Hydroxycobalamin (cyanokit): standard, more severe cases
Hydrogen cyanide kit: amyl nitrate, sodium nitrite and sodium thiosulfate (traditionally - but causes methemoglobinemia and worsens hypotension)
Nithiodote: amyl nitrate, sodium nitrite and sodium thiosulfate
Sodium thiosulfate- only option available or for less severe cases
73
whats the problem with traditional hydrogen cyanide kit
- amyl nitrate, sodium nitrite and sodium thiosulfate.
- They cause methemoglobinemia which has high affinity for cyanide -> forms complex + thiosulfate -> complex that can be excreted (often pts have CO too...)
- Nitrites also cause hypotension.
74
hydroxycobalamin dose and results
5g over 15 min / 70 mg/kg in kids
binds to CN -> B12 -> excreted
raises BP and turns things red
75
what is the toxin in castor beans, MOA and toxicity
ricin
inhibits RNA synthesis - cell death
inhaled (pulm issues), injected (MSK death), ingested (GI organ injury)
76
stages of iron toxicity
GI upset
AGMA/lactate and shock
Hepatic failure
GI mucosal healing- scarring and strictures
77
toxic dose of iron
>60 mg/kg
20 - 60 mg/kg
78
toxic iron levels
@4 hours
<300 mcg/dl = asymptomatic
300 - 500 = GI symp, TREAT
> 500 = shock and bad news
79
iron toxicity treatment and dose
Deferoxamine (11mg binds 8.5mg elemental iron)
5-15 mg/kg/h
80
side effects of deferoxamine (3)
Anaphylactoid, ARDS, yersinia infection
often take holiday after 24 hours and reassess
safe in pregnancy
81
3 iron formulations and percentage of elemental iron
Fumarate 33%, sulfate 20%, gluconate 12%
82
Digoxin
- indications
- MOA
- therapeutic range
- excretion and interactions
A fib with low BPs, HFrEF failing GDMT, peds HF
NA/K ATPase inhibition -> increase Ca and contractility
0.5-1 ish : NARROW
RENAL excretion. Many interactions including amiodarone and macrolides
83
Other sources of digitalis toxicity
foxglove, lily of the valley, yellow oleander, colorado river and cane toad, squill
84
Presentation of Dig toxicity
Nonspecific: fatigue, confusion, N/V, HA, anorexia
CARDIAC: anything, bradycardia, heart block, v tach, hypotension
HyperK, Hypomag, renal failure
Pathognomonic - bidirectional V tach
85
electrolyte derangements with dig toxicity
HyerK
HypoMag
Renal failure
86
Indications to give digoxin fab
Dysrhythmia
Hypo, brady
K >5 in acute (>5.5 portends bad prognosis)
Chronic with AMS, dysrhythmia or GI symptoms
87
K of what portends bad prognosis in dig toxicity
> 5.5
88
dig tox treatments (and contraindicated!) besides dig fab
Charcoal (multi-dose)
magnesium
?atropine
?Class IB antiarrhythmics like phenytoin or lidocaine
Calcium contraindicated (stone heart)
No pacing
HD (Vd too big)
89
Digoxin Fab MOA and dosing
binds digoxin with higher affinity and is excreted in urine
each vial is 40mg and binds 0.5 mg
oral bioavailability 80%
Number of vials in Acute = (mg ingested x 0.8.) / 0.5 = 1.6 x mg ingested
Imminent arrest: 5-10 vials
Chronic = (serum dig x weight) / 100
90
formulas to decide how much dig fab to give in acute and chronic ingestions
Number of vials in Acute = (mg ingested x 0.8.) / 0.5 = 1.6 x mg ingested
Imminent arrest: 5-10 vials
Chronic = (serum dig x weight) / 100
round up!
91
serotonin syndrome VS NMS
- serotonin: rapid- tremor, seizures, myoclonus, hyperreflexia. treat with benzos and cyproheptadine
- NMS: gradual- bradykinesia, lead pip rigidity, hyperthermia. treat with benzos, bromocriptine, levodopa
92
presentation of SSRI/SNRI OD
GI
CNS- drowsy tremulous, seizures, ataxia
CV: sinus tach, NA channel blockade and QRS prolongation, QT prolongation
93
EKG finding and management of TCA overdose
widened QRS
terminal R wave in avR
Na bicarb
intralipid
94
treatment of TCA OD
Na bicarb
- intralipis
95
Alkali caustic examples and results
hydroxide, hydrogen peroxide
liquifactive necrosis
96
Acidic caustic examples and results
Hydrochloric, sulfuric, hydrofluoric acid
coagulative necrosis
97
ingestion of caustic, worrisome clnical signs
stridor by itself
drooling and vomiting
predictive of esophageal injury
98
which caustic has unique dermal decon
phenol: use propranolol or isopropranolol
visible metals- wipe off
99
in caustic ingestion, who gets scope?
- intentional ingestion
-AMS or baseline behavioral
- stridor
- vomiting and drooling
not needed if unintentional, no symptoms x8 hours and tolerating PO
100
treatment post endoscopy of caustic ingestons
- IF 2B -> methylpred
abx only for perf
PPI theoretical
101
MOA, presentation, treatment methemoglobinemia
Fe2+ -> Fe 3+ -> left shift and thus functional anemia and los SpO2
methylene blue reduces it: 1-2 mg/kg over 5 min
102
causes methemoglobinemia
amyl nitrate, silver nitrate, local anesthetics, abx, phenazopyridine, phenacetin, oxides
103
presentation and management of hydrofluorocarbon
- CNS depressant and asphyxiant
- sudden sniffing death 2/2 tachydysrhythmias from catecholamine surge
- NO EPI
- propranolol or eosmolol
104
pyrethrins/pyrethroids, where are they and MOA, treatment
- mosquito netting, topical for scabies and life
- Na channal openers -> tremors, seizures, ataxia, cardiac effects
- Vit E, benzos
105
MOA HF acid
rapid release of hydrogen ions and subsequent tissue dehydration and coagulation necrosis, binds up all your calcium and causes vasospasm
the release of the highly reactive free fluoride ion, F– (liquefactive necrosis)
106
acids and alkali type of necrosis
Acids: coagulative necrosis
alkali: liquefactive necrosis.
107
deforoximine ??mg binds???
100 mg binds 8.5 mg
108
symptoms CN
headache, seizure, coma, resp failure, tachycardia followed by bradycardia, AGMA
cherry red skin is late finding
109
VPA: MOA, level, presentaiton, treatment
- inreased GABA, impairs mitochondrial beta oxidation, depletes carnitine stores and disrupts urea cycle
- acute ingestion>200 mg/kg
- sx: n/v, pancreatitis, CNS depression, AGMA, hyperammonemia, hypotension, pancytopenia
get serial levels
- tx: L-carnitine for encephalopathy with hyperammonemia (VPA 450 mg/L), meropenem, HD (VPA > 850 mg/L, cerebral edema)
110
Tessalon MOA and treatment
NA channel blockade - seizures and dysrhythmias
- inralipid, bicarb, benzos
111
cyclopeptide mushrooms example and phases
amanita phalloides with amatoxin- inhibits RNA polymerase II
Phase 1 (5-24h) terrible GI sx; phase 2 (12-36h) minimal symptoms that can be falsely reassuring; phase 3 (2-6d) hepatic/renal failure, death
112
gyromitra mushroom / false morel
False Morel- BRAINS< PYRIDOXINE
Gyromita toxin: metabolized to monomethylhydrazine which acts like isoniazid to deplete B6 → no glutamate to make GABA → refractory seizures
Consider pyridoxine for seizures (you need like 50 vials)
113
muscarine mushrooms
Ivory tunnel
CHOLINERGIC - NO BBB cross
114
amanita smithiana
- contains?
- preentation?
BREAKS 6 HOUr RULE
- contains crotylglycine and allenic norleucine
R- apid N/V <6h (breaks the 6h rule), delayed renal failure with peak Cr @ 2-7d
115
foxglove
digitalis
116
jimson weed
anticholinergic
117
phytolaccatoxin
GI syjptoms
118
hallucinogenic plants
Morning glory/nutmeg/claviceps, hawaiian baby wood rose, kava kava, kratom, salvia
119
convulsant plants
water hemlock/strychnos
120
Na channel blocking plants
rhododendron/false hellebore/death camus/monkshood/yew (& Ca+ channel blocker)
121
Trazodone MOA
Alpha 1 agonist, H1 and 5HT2A/2C antagonist, 5HT1 agonist → CNS depression, hypotension
122
fresh mown hay
phosgene
akasthesia
benzo, propranolol 20 mg BID to 80 mg/day, clonidine 0.1 mg TID, 5HT2A antagonist (mirtazapine, cyproheptadine)
123
which SSRI's are cardiotoxic
citalopram/escitalopram
124
organophosphate available at lowes
carbomyl
125
colchicine plant
antimitotic (tubulin) -> multiorgan failure
autumn crocus and glory lily
highest concentration in bulb
126
what heavy metal causes torsades
aresenic
127
what lead level is toxic
500 at 4 hours
128
4 ways NAC works
▪ Limits further formation of NAPQI
▪ Acts as precursor for glutathione
▪ Improves microvascular blood flow/oxygen delivery
▪ Increases capacity to detoxify NAPQI
