tox and environmental

Question 1

GHB overdose sx

Answer 1

slow: CNS depression, hypoventilation, bradycardia
fast: myoclonus, seizures

Question 2

GHB withdrawal sx

Answer 2

agitation, delirium, seizures

Question 3

beta-blocker overdose tx

Answer 3

fluids and pressors
insulin 1u/kg bolus
glucagon 5q10 x 3 doses
intralipid

Question 4

CCB overdose tx

Answer 4

insulin 1u/kg bolus
calcium gluconate 3g
intralipid

Question 5

dig overdose tx

Answer 5

Digibind 10-20 vials

Question 6

heroin overdose tx (and when to use it)

Answer 6

opioid-naive: 0.4 mg IV
opioid-dependent: 0.04-0.1 mg (to prevent inducing withdrawal)

when to use it: obtunded, miotic, RR < 12, and O2 sat < 90% (all others can be observed)

*in all cases: may uptitrate to max 10 mg

Question 7

organophosphate overdose tx

Answer 7

atropine 2 mg, double q5-30m until secretions controlled –> pralidoxime 1-2g over 15-30m

Question 8

dig: 2 pathognomonic EKG findings

Answer 8

PAT w/block (rare)

bidirectional VT

Question 9

dig: most common dysrhythmia

Answer 9

PVCs

Question 10

dig: most common EKG change

Answer 10

Salvador Dali STs

Question 11

regularized afib

Answer 11

dig toxicity

Question 12

naloxone: onset of action

Answer 12

1-6 mins depending on route

Question 13

naloxone: duration of effect

Answer 13

20-90 mins depending on route

Question 14

naloxone gtt dose

Answer 14

2/3 wake-up dose

Question 15

check this before giving physostigmine

Answer 15

EKG (for blocks, TCA)

Question 16

Librium taper

Answer 16

6 50 mg tabs

• day 1: 1 tab TID
• day 2: 1 tab BID
• day 3: 1 tab

Question 17

naloxone: full dose

Answer 17

2 mg

Question 18

black widow vs brown recluse

Answer 18

black widow: neurotoxins (ACh and NE) > fake appy, neuroexcitation opioids and benzos, antivenin if severe
brown recluse: cytotoxic enzymes > local tissue necrosis (no antivenin)

Question 19

cholinergic toxidrome

Answer 19

SLUDGE and killer Bs (bradycardia, bronchorrhea, bronchospasm)

Question 20

dextromethorphan toxidrome

Answer 20

like PCP: CNS sx like visual hallucinations, rotary nystagmus, tachycardia (reliable), mydriasis, hyperthermia

Question 21

APAP overdose mechanism

Answer 21

overdose overwhelms normal metabolic pathways (sulfation and glucuronidation), shunting the rest of of the APAP to the CYP450 pathway which generates NAPQI, which requires glutathione to detox it
rapid depletion of glutathione stores leads to NAPQI accumulation and hepatotoxicity

Question 22

acute mountain sickness: tx

Answer 22

halt ascent, Diamox (except in sulfa allergy)

Question 23

decompression sickness

Answer 23

gas bubbles go free > obstruct/inflame tissues/vasculature mins/hours after surfacing

• type 1: joints (“bends”), skin (mottling), extremity lymphatic obstruction
• type 2: cardiopulmonary (“chokes”), neuro (“staggers”), upper lumbar/lower thoracic spine pain

tx is like arterial air embolism: supine position, O2, increase tissue perfusion (IVF), recompression (hyperbaric)

Question 24

When does pulmonary barotrauma occur?

Answer 24

ascent

Question 25

When do sinus squeeze and inner ear barotrauma occur?

Answer 25

descent

Question 26

VPA toxicity

Answer 26

N/V, encephalopathy, hyperammonemia | tx: charcoal, L-carnitine, HD

Question 27

how to dose bicarb in TCA toxicity

Answer 27

50 mEq IV at a time until QRS narrows | then gtt @150 mEq in 1L D5W at 2-3xM

Question 28

When do you stop cooling a hyperthermic pt?

Answer 28

39 degrees, to avoid overshoot

Question 29

cyclosporine can cause

Answer 29

hyperK, hyperuricemia, HTN, nephrotoxicity

Question 30

azathioprine can cause

Answer 30

marrow suppression, pancreatitis, hepatitis, jaundice

Question 31

oil of wintergreen toxicity and blood gas

Answer 31

highly-concentrated ASA (deadly to a kid) | early resp alkalosis, later gap metabolic acidosis

Question 32

myasthenia pathophysiology

Answer 32

autoantibody binds nicotinic ACh receptors > prevents ACh binding > neuromuscular weakness

Question 33

tetanus toxin pathophysiology

Answer 33

prevention of presynaptic release of inhibitory neurotransmitters (GABA and glycine)

Question 34

botulinum toxin pathophysiology

Answer 34

inhibition of presynaptic release of ACh > flaccid paralysis

Question 35

NAC mechanism

Answer 35

restores glutathione

Question 36

What dose of acetaminophen is typically required to cause significant liver damage?

Answer 36

150 mg/kg or greater

Question 37

sudden sniffing death syndrome

Answer 37

hydrocarbon ingestion > catecholamine surge > ventricular dysrhythmia avoid procainamide, sotalol, amio (classes IA and III)

Question 38

calcium channel blocker toxicity tx

Answer 38

glucagon (although this works more w/beta-blocker toxicity) calcium chloride high-dose insulin epinephrine

Question 39

when to avoid rewarming in frostbite

Answer 39

if there's a risk of refreezing

Question 40

trench foot

Answer 40

prolonged wet/cold (but nonfreezing) exposure causing reversible neurovascular injury just the toes = chilblains

Question 41

symptom of early radiation exposure

Answer 41

vomiting

Question 42

when to antibiose animal bites

Answer 42

cat bite wound requiring closure immunocompromised pt hand/genitalia

Question 43

danger of physostigmine

Answer 43

asystole

Question 44

drugs associated with noncardiogenic pulmonary edema

Answer 44

meprobamate, opioids, Narcan, PCP, aspirin

Question 45

isopropyl EtOH tx

Answer 45

supportive, sometimes HD

Question 46

methanol tx

Answer 46

fomepizole

Question 47

ethylene glycol tx

Answer 47

fomepizole

Question 48

methylene chloride toxicity mimics

Answer 48

CO poisoning

Question 49

electrolyte abnormality that worsens dig toxicity

Answer 49

HYPOkalemia