Toxicology

Question 1

siallorhea, mydriasis, diaphoresis, hyperactive bowel sounds, hyperreflexia, increased muscle tone

Answer 1

Serotonin Syndrome

Question 2

dry muycosa, hot red dry skin, mydriasis, normal reflexes and tone

Answer 2

anticholinergic

Question 3

Lead pipe rigidity, bradyreflexia, normal pupils, fever, diaphoresis, delirium after DA agonist

Answer 3

NMS

Question 4

Rigor mortis type of rigidity, hyporeflexia, normal pupils and mucosa, mottled skin and diaphoresis, temp very high

Answer 4

Malignant Hyperthermia

Question 5

inherited sarcomere disorder that is triggered by inhalational anasthesia or succ shortly after surgery

Answer 5

Malignant Hyperthermia

Question 6

Drugs that can lead to serotonin syndrome

Answer 6

SSRI, MOA, analgesics, antiemetics, linezolid

Question 7

treatment for severe serotonin syndrome

Answer 7

benzos, cyproheptadine

Question 8

NMS treatment

Answer 8

bromocrintpine- increase CNS dopamine

Question 9

dantrolene use? MOA? when to use?

Answer 9

reduces excitation- contraction uncoupling in muscles

- can be used to tx hyperpyrexia in SS, NMS, MH

Question 10

normal metabolism of acetaminophen?

Answer 10

most is glucoronidation to a non toxic metabolite by the liver. A small amount is by the CYP450 system into NAPQI which is toxic

Question 11

MOA of acetaminophen toxicity?

Answer 11

large doses depletes glutathione and overwhelms the glucoronidation pathway shifting to more NAPQI formation

Question 12

MOA of NAC?

Answer 12

replenishes glutathione stores

Question 13

what is the Rumack Mathew nomogram?

Answer 13

plots serum concentation vs time after ingestion to determine whether or not to treat

Question 14

when should you not use the Rumack Matthew nomogram?

Answer 14

taking acetaminophen chronically, chronic alcohol abuse, chronic liver disease, time of overdose is not reliable

Question 15

Malignant Hyperthermia presentation

Answer 15

it is due to hypermetabolism and releasing a large quantity of calcium from the SR after triggering agent like succ
- inc CO2 production, inc O2 consumption, combined resp and metabolic acidosis, heat production, sympathetic upregulation, hyperkalemia, can see seizures but rare

Question 16

tx of MH?

Answer 16

cooling, stop offending agent, dantrolene

Question 17

cyanide toxicity most common cause?

Answer 17

smoke from a building fire

Question 18

MOA of cyanide poisoning?

Answer 18

inihibits mitochondrial oxydative phosphorylation and shift to anaerobic metabolism leading to lactic acidosis

Question 19

treatment of choice for cyanide poisoning?

Answer 19

hydroxycobalamin- converts HCN to B12

Question 20

TOC of methemoglobinemia?

Answer 20

methylene blue-converts the MHG to hgb

Question 21

toxic metabolite of methanol?

Answer 21

formic acid

Question 22

toxic metabolite of ethylene glycol?

Answer 22

oxalic acid, glycolic acid

Question 23

where do you find ethylene glycol?

Answer 23

antifreeze, cleaning products

Question 24

where do you find methanol?

Answer 24

anti freeze, moonshine

Question 25

which toxic alcohol leads to blindness?

Answer 25

methanol

Question 26

what happens to the osmolar gap and AGAP over time in toxic alcohol ingestion?

Answer 26

osmol gap decreases and AGAP increases, some recommend to just check anion gap serially because osmol gap is not reliable

Question 27

when to start fomepizole?

Answer 27

high index of suspiscion wiht an AGAP tht continues to rise without another explanation

Question 28

lactate gap in ethylene glycol ingestion, explain?

Answer 28

glycolate that is a toxic metabolite in EG breakdown mimics lactate. So if there is a high lactate on blood gas machine because it measures lactate differently than lab assays

Question 29

reasons to start fomepizole?

Answer 29

ingestion history and very high anion gap without other cause

Question 30

why does fomepizole dosing need to be increased over the time iots being given?

Answer 30

it induces its own metabolism

Question 31

should you give bicarbonate to patient with toxic alcohol ingestion?

Answer 31

yes if they are acidotic. - normalizing the pH can keep the toxic metabolites in their ionized state and thus less able to penetrate tissues such as brain and eye

Question 32

signs and sx of lithium toxicity

Answer 32

GI symptoms, prolonged QT interval | - chronic toxicity can lead to nephrogenic DI or chronic neuro sx, grand mal seizures

Question 33

osmol gap | calculated osmolality

Answer 33

measured- calculated normal <10 | - (2xNa)+(glc/18)+(BUN/2.8)+(ethanol/3.7)

Question 34

how is isopropyl alcohol intoxication different than methanol and ethylene glycol?

Answer 34

- no acidosis - breaks down into acetone so you will see extremely high ketones in the urine - but will still see a osmol gap