Antidotes for toxicological emergencies

Question 1

what is the toxic metabolite of methanol and what are the consequences?

Answer 1

formic acid formed by alcohol dehdyrogenase

metabolic acidosis and ocular toxicity

Question 2

what is the toxic metabolite of ethylene glycol (antifreeze) and what are the consequences?

Answer 2

glycolic acid; metabolic acidosis and CNS tox

oxalic acid; renal toxicity and CNS tox

Question 3

what are the antidotes to ethylene glycol and methanol?

Answer 3

both are ethanol and fomepizole

Question 4

what are the side effects of ethanol?

Answer 4

CNS depression
hypoglycemia (dec gluconeogenesis)
nausea/vomiting

Question 5

what is the mechanism of action of fomepizole?

Answer 5

completely inhibits ADH which does not allow the toxic metabolites of ethylene glycol and methanol glycol to manifest (toxic metabolites not made)

Question 6

what are the adverse effects wit h the use of foempizole?

Answer 6

mild irritation at the IV infusion site
HA
nausea
dizziness, drowsiness and 
A bad metallic taste

Question 7

why is fomepizole preferred over ethanol as the treatment?

Answer 7

ease of administration
lack of serious adverse effects
higher potency of ADH inhibition
better maintenance of therapeutic blood concentrations.

Question 8

how should methanol toxic patients be managed?

Answer 8

1. give fomepizole or ethanol
2. hemodialysis if anion gap metabolic acidosis or end organ damage
3. serum methanol concetration is >25mg/dL
4. 50mg of folic aside every six hours enhances methanol elimination.

Question 9

what are the side effects of calcium channel blockers and beta blockers in overdose?

Answer 9

hypotension
bradycardia
conduction block
possible cardiac collapse depeding on PMH

Question 10

how can you differentiate CCB from beta blocker toxicity?

Answer 10

CCB 
-remain awake and alert
-more likely to cause hyperglycemia
Beta blocker 
-have altered mental status and resp depression
-children likely to develop hypoglycemia

Question 11

which beta blocker in overdose is most likely to cause wide QRS and a seizure?

Answer 11

propanolol

Question 12

what agents can be involved in the management of a patient with CCB and beta blocker toxicity?

Answer 12

1. fluids
2. atropine
3. calcium
4. glucagon
5. Insulin (HIET)
6. vasopressors
7. intralipid
8. caridiac pacing

Question 13

how does calcium work in treating CCB or Bblocker toxicity?

Answer 13

giving exogenous calcium should competitively increase calcium entry into the myocardium through non blocked channels

Question 14

what is the conversion between calcium gluconate and calcium chloride?

Answer 14

30mL of 10% CG=10L of 10% CC

Question 15

what are the signs and symptoms of hypercalcemia?

Answer 15

• ileaus
• myocardial depression
• hyporefelxia
• AMS

Question 16

should digoxin and calcium be used together?

Answer 16

NO! can lead to asystole

Question 17

what is a starting dose of calcium and how many times can it be administered?

Answer 17

30mL of calcium gluconate or 10ml Ca Carb
additional dose administered in 15-20 minutes. After 3 dose, artful monitoring of ionized calcium necessary to avoid hypercalcemia

Question 18

what is the MOA of glucagon in hypotensive bradycardic patient?

Answer 18

increases CAMP directly and indecently of the B adrenergic receptor. Inc in cAMp increases inotropy and chronotropy and may improve conduction

Question 19

what are the side effects of glucagon?

Answer 19

• nausea
• vomiting with a risk of aspiration (usually given with metoclopramide and serotonin antagonists)
• hyperglyciemia
• GI smooth muscle rleaxation and diarrhea
• hypokalemia

Question 20

what is a typical dose of glucagon?

Answer 20

50 micrograms/kg or 3-5mg up to a cumulative dose of 10mg

Question 21

Why do we use high dose insulin for bradycardic hypotensive patients ?

Answer 21

Has long been reported to be an ionotrope. Unknown mechanism but we know it affects energy metabolism of heart cells

Question 22

How long does high dose insulin therapy tend to take to work?

Answer 22

15-60 min

Question 23

What are the two main side effects of insulin therapy?

Answer 23

Hypoglycemia

Hypokalemia

Question 24

What are the names of the kits used for antidotes to cyanide poisoning?

Answer 24

• cyanide antidote package
• cyanide antidote kit
• nithiodote
• cyanokit

Question 25

What is the active ingredient in cyanide antidote package and kit?

Answer 25

Amyl nitrite
Sodium nitrite
Sodium thiosulfate

Question 26

What is the active ingredient of nithiodote

Answer 26

Sodium nitrite

Sodium thiosulfate

Question 27

What is the active ingredient in cyanokit

Answer 27

Hydroxycobalamin