Toxicology Flashcards
1
Q
Tox: smell of bitter almonds
A
cyanide
2
Q
Tox: smell of garlic
A
organophosphates, arsenic
3
Q
Nerve agents e.g. sarin cause what toxidrome
A
Cholinergic
4
Q
Examples of anticholinergic agents
A
atropine, antihistamines, antiparkinson’s meds (benztropine)TCAs, Jimson weed, nightshade
5
Q
Sympathomimetic medications
A
decongestants (ephedrine, pseudoephedrine), theophylline, ephedra (chinese medicinal)
6
Q
Calculate AG
A
Na - (HCO3 + Cl)
7
Q
ABCDEF of Tox
A
airway, breathing, circ, decontamination (skin, eyes - irritgate until neutral pH, clothing), enhanced elimination, focused therapy (antidote)
8
Q
Activated charcoal; administer within ___. Dose
A
1 hr, 1 g/kg
9
Q
Charcoal contraindications (4)
A
Non-intact GI tract, unprotected airway, caustic ingestion, hydrocarbon ingestion
10
Q
Could consider gastric lavage under what circumstances
A
<1 hr since ingestion, fatal amt, no antidote
11
Q
When can you use urine alkalinization? How is this done?
A
weak acids e.g. salicylates. Sodium bicarb (3 amps in 1L D5W
12
Q
Toxins amenable to dialysis
A
“I STUMBLE” isopropanol, salicylates, theophylline, uremia, methanol, barbituates, lithium, ethylene glycol
13
Q
Antidote for methanol and ethylene glycol
A
fomepizole
14
Q
Antidote for benzos
A
flumazenil
15
Q
Antidote for anticholinergics
A
physostigmine
16
Q
Antidote for organophosphates
A
atropine or pralidoxime
17
Q
Antidote for cyanide
A
nitrites and thiosulfate
18
Q
Antidote for Iron
A
deferoxamine
19
Q
Antidote for arsenic or lead
A
BAL (chelator)
20
Q
Antidote for digoxin
A
digifab
21
Q
Antidote for rattlesnake bite
A
Crofab
22
Q
Antidote for beta blockers
A
glucagon
23
Q
Antidote for TCAs
A
sodium bicarb
24
Q
Antidote for CCBs
A
calcium, insulin/dextrose
25
Medication that can cause seizures and its antidote
isoniazid -> give pyridoxine
26
Pediatric ativan and versed dosing for seizure/status
ativan 0.1 mg/kg up to 4 mg. Versed 0.2 mg/kg up to 10 mg.
27
Toxic level of tylenol at 4 hrs
150 mg/mL or greater
28
When can the Rumack-Matthew nomogram not be used
chronic toxicity or >24hrs since ingestion
29
Want NAC to be given within what time frame? What do you do if they're past that time frame?
8 hrs. For presentation >8 hrs, give NAC right away before level comes back.
30
Dispo for delayed, large APAP OD
ICU at a TRANSPLANT center
31
Febrile + seizure in tox world
Salicylates
32
Indications for dialysis with salicylate OD (4)
salicylate >100 mg/dl acutely (60 subacute), noncardiogenic pulmonary edema, seizure, AMS
33
Ongoing labs for salicylate ingestion
q2H
BMP: replace K+ as needed
ABG: ?adequate alkalinization, goal pH 7.5
Salicylate levels: sporadic absorption d/t bezoars
34
Kid takes grandma's "heart med" or antihypertensive, or ingestion comes in brady and hypotensive... most likely meds they'll test and associated lab
BB (BG may be low), CCB (BG may be elevated), digoxin (check dig level), clonidine
35
Escalating treatment of BB/CCB OD
charcoal, fluids, atropine, glucagon (BB)/calcium (CCB), high dose insulin (0.5-1 U/kg/hr = 10x DKA treatment), pacing, intra-aortic balloon pump
36
yellow vision change = toxic effect of _____
digoxin
37
bidirectional V-tach pathognomonic for what
cardiac glycoside (e.g. digoxin) toxicity
38
Empiric dosing of digifab
10-20 vials (same for adult or child)
39
What is different about managing hyperkalemia in digoxin OD?
Avoid CALCIUM. Can --> "Stone heart". Treat hyperkalemia with digifab (indicated for K >5.0)
40
Escalating treatment of TCA OD
Charcoal. Sodium bicarb (1-2 mEq/kg push), repeat until normal QRS. Hold if pH >7.55. Intubation if needed. Benzos for seizures.
41
Toxic effects on antipsychotics and associated treatments
HypoTN (fluids), anticholinergic, antidopaminergic (EPS - dystonia, NMS -> give benadryl or benztropine), sodium channel blockade -> long QRS (give NaHCO3)
42
Symptoms of iron toxicity
Early 2-6 hrs: corrosive, vom/dia - possibly bloody
Improvement over 12 hrs
Later: get worse, coma, shock, seizure, acidosis, liver failure, death
43
Lead toxicity sx
Neuro: lethargy, coma, seizure, ataxia, foot and wrist drop
GI : abd pain, constipation, anorexia
Heme: anemia
Renal: nephropathy
44
Lead toxicity - chelation treatment needs
Often once chelator is stopped (which bound serum lead), source of lead within the body continues leaching and levels rise again --> need for OP f/up for repeat lead level, possible need to repeat chelation
45
Clues to methemoglobinemia
Pt appears cyanotic, chocolate brown blood (occurs at 15-20% methgb, pulse ox 85%. At 50+% -> dysrhythmias, seizures, coma
46
Triggers for methemoglobinemia
benzocaine, dapsone, pyridium, nitrates, aniline dye
47
Methylene blue contraindicated with ____
G6PD deficiency (causes hemolysis)
48
Escalating treatments for methemoglobinemia
oxygen, methylene blue (20% and symptomatic or 30%+).
| Refractory: HBO, exchange transfusion
49
Work up for suspected CO poisoning
CMP, CBC, carboxyhgb level, ECG (evidence of ischemia?), ABG, CK (rhabdo?), pregnancy test (changes threshold), CT head (cerebral edema or basal ganglia defects)
50
Indications for HBO with CO
CO >25%, pregnancy with fetal distress, LOC, neuro symptoms other than simple HA, abnl neurocog testing, ischemic ECG or cardiac complication.
51
Management of mild to mod CO poisoning
100% O2 e.g. NRB mask (5x as long if preg). Repeat COHb level q2-4H until <5% if pregnant or <10% for everyone else
52
Fire + severe metabolic acidosis --> think ____
cyanide
53
Brady or tachy?
CO -->
Cyanide -->
CO - tachy
| Cyanide - brady, hypotension
54
Cyanide poisoning tx
Decontaminate incl skin and clothing
Charcoal
If symptoms + presumed cyanide = treat. Options
- Hydroxocobalamin (binds CN)
- Amyl nitrite inhalation (until IV access)
- sodium nitrite (forms cyanmethemoglobin, binding cyanide)
- Sodium thiosulfate: binds #2 --> less toxic
Cyanocobalamin, secreted
55
Hydrocarbons: MC agents
oils: lamp oil, kerosene, gas, mineral seal oil
56
Hydrocarbons: effects (4 main systems)
Resp: aspiration, pulmonary edema, respiratory arrest
GI: N/v/abd pain
CNS: Confusion, ataxia, lethargy
Card: myocardial sensitization to catechol - don't give epi, NE, or scare the pt :) Give BB if dysrhythmias
57
When could you discharge a hydrocarbon ingestion
accidental, CXR normal, 6hrs monitoring w/o resp effects or other symptoms. Consider repeat CXR around 6 hrs to look for evolution
58
Work up for all ingestions
CMP, CBC, APAP, ASA, ETOH, UPT, UA (?crystals)
| ?ABG, ?CXR
59
Organophosphate treatment
atropine: start 0.5-2mg, titrate to secretions, bronchospasm, bronchorrhea - may give 100mg+ eventually!
pralidoxime: regenerates cholinesterase
60
Intubating a organophosphate OD - remember _____
No SUCC! (cannot break it down)
61
Ethylene glycol and methanol tx (multistep)
Fomepizole/ethanol. NaHCO3 for profound acidosis, serial rechecks and replacement of electrolytes and glucose. Dialysis.
62
Indications for dialysis with ethylene glycol or methanol
Elevated osmolal gap, significant acidosis, serum ethylene glycol or ethanol level >20 mg/dL
63
Max single dose (not cumulative) narcan
10 mg
64
Level to start narcan drip at
2/3 of successful single dose per hour
65
MC agents for anticholinergic OD
benadryl, TCA
66
Anticholinergic-induced dystonia or choreoathetoid movements tx
benzo
67
Severe anticholinergic with hyperthermia... next steps
intubate, neuromuscular blockade, continuous EEG to ensure no sz while on paralytic
68
Physostigmine indications and contraindications
Indications: avoid tube, treat seizures, severe agitation
Contra: TCA OD
69
Labs specific to meth/cocaine OD with hyperthermia
CK
70
Serotonin syndrome symptoms
hyperthermia, flushing, muscle rigidity, AMS, hyperreflexia, incoordination, myoclonus, diarrhea
71
Serotonin syndrome specific labs
CK, UA, DIC labs
72
Causes of serotonin syndrome
SSRIs, MAOIs, amphetamines incl ecstasy
73
Serotonin syndrome escalating treatments
benzos, cooling, intub/neuromusc blockade
74
Serotonin syndrome vs NMS presentation differences
little - just serotonergic vs neuroleptic agents as etiology
75
NMS - can consider this pseudoantidote
bromocriptine (treats relative dopamine depletion)
76
Valproic acid OD - check what lab
ammonia
77
theophyllin + seizure =
dialysis
78
What's weird about iron toxicity presentation?
Quiescent middle phase
79
Lead + encephalopathy = _____ therapy
BAL and CaNaEDTA
80
Severely acidemic, comatose chemist: toxicity?
cyanide
81
Hypothermia mgmt
remove wet clothing, warm, monitor core body temp
82
Hypothermia work up
look for precipitant; BG, electrolytes, alc, TSH/T4, ABG, ECG, coags, CT head if AMS/evidence of trauma
83
Hypothermic with cardiac arrest mgmt
call for cardiac or thoracic surgeon for cardiopulm bypass to warm
84
Hypothermia + ventricular rhythm - def max # times
3
