acetaminophen OD

Question 1

IV acetaminophen

Answer 1

ofirmev

Question 2

lab indicator of acetaminophen toxicity

Answer 2

elevated ALT values

Question 3

problem of opioids+acetaminophen

Answer 3

addicitve drug+ dose dependant toxin = bad trouble

Question 4

2011 upper dose limit with opioids

Answer 4

325/tablet

Question 5

reduced daily dose of APAP

Answer 5

3 gm/day in adult

Question 6

dosage than can cause liver damage

Answer 6

4gm/2 hr (adult)

Question 7

absorption time of APAP in theraputic dose

Answer 7

1 hr

Question 8

absorption time of APAP in OD

Answer 8

4 hr

Question 9

type of metabolism in APAP

Answer 9

1st order

Question 10

elimination t 1/2 in normal dose of APAP

Answer 10

2.5 hours

Question 11

anti-inflamatory effect of APAP

Answer 11

weak

Question 12

advantages of APAP

Answer 12

no effect on neutrophil activation, not a gastric irritant, no effect on bleeding

Question 13

mechanism of liver metabolism of APAP

Answer 13

90% glucuranidation or sulfation then elminated by kidneys

Question 14

toxic metabolite of APAP

Answer 14

NAPQI

Question 15

enxyme converting APAP to NAPQI

Answer 15

CYP P450

Question 16

detoxes NAPQI endogenously

Answer 16

glutathione

Question 17

mech of toxicity in APAP OD

Answer 17

normal pathways overwhelmed
NAPQI built up
glutathione depleted
NAPQi binds to proteins, forming adducts
ROS damages hepatocytes

Question 18

drug that induces more CYP2E1 and accelerates APAP toxicity

Answer 18

EtOH

Question 19

reason alchoholics are susceptiple to APAP toxicity

Answer 19

loss of glutithione

Question 20

APAP toxic dose in child

Answer 20

150 mg/kg

Question 21

APAP toxic dose in adult

Answer 21

10g

Question 22

theraputic dose in kids

Answer 22

75 mg/kg

Question 23

time of phase 1 APAP toxicity

Answer 23

.5 to 24 hours

Question 24

time of phase 2 APAP toxicity

Answer 24

24-72 hours

Question 25

time of phase 3 APAP toxicity

Answer 25

72-96 hours

Question 26

time of phase 4 APAP toxicity

Answer 26

4-14 days

Question 27

sx of Phase 1 APAP toxicity

Answer 27

N/v, elevated liver enzymes (possibly asymptomatic)

Question 28

sx of Phase 2 APAP toxicity

Answer 28

RUQ abdom tenderness, elevated ALT/AST, clotting factors impaired

Question 29

sx of Phase 3 APAP toxicity

Answer 29

jaundice, coagulation defects, hepatic encephalopathy, renal failure, death

Question 30

sx of Phase 4 APAP toxicity

Answer 30

death, or resolution of liver failure

Question 31

treatment for acute APAP toxicity

Answer 31

N-acetylcysteine (NAC)

Question 32

MOA of N-acetylcysteine (NAC)

Answer 32

glutathione substitute - detoxes NAPQI

Question 33

risks of N-acetylcysteine (NAC) IV

Answer 33

possible anaphylaxis

Question 34

how much higher is the risk of liver failure if treatment with MAC is over 10 hours

Answer 34

4x

Question 35

adverse effects of N-acetylcysteine (NAC)

Answer 35

lots of vomiting, anaphylaxis with IV

Question 36

prevention of anaphylaxis in IV N-acetylcysteine (NAC)

Answer 36

preload with antihistamines and steroids

Question 37

indications of treatment with N-acetylcysteine (NAC)

Answer 37

hx of toxic injestion
right of line in rumack nomigram
elevated ALT

Question 38

axes of Rumack nomogram

Answer 38

X - Serum APAP

Y - hours from OD

Question 39

approx APAP serum level to treat after 4 hours

Answer 39

> 200

Question 40

limitations of Rumack

Answer 40

applies only to acute ingestions
not as valid in Kids
limited to 24 hours
does not handle extended release pills, or EtOH
not for chronic OD

Question 41

time frame to induce vomiting in APAP OD

Answer 41

<2 hours

Question 42

indication for liver transplant referral

Answer 42

encephalopathy, uncontrolled liver enzymes