Alcohol

Question 1

what is the osmol gap

Answer 1

difference between the measured osmolality and calculated osmolarity

Question 2

what is osmolarity

Answer 2

measure of the total number of particles in one litre of solution - calculated

Question 3

what is osmolality

Answer 3

number of particles in kg of solution - measured

Question 4

osmolarity (mmol/L) formula

Answer 4

2 x Na + glucose + BUN

all concentrations in mmol/L

Question 5

normal BUN levels

Answer 5

3- 7.1mmol/L

8-20 mg/dL

Question 6

other dumb formula for osmolarity

Answer 6

2 x NamEq/L + glucose mg/dL/18 + BUNmg/dL/2.8

Question 7

measurement of osmolality

Answer 7

freezing point depression

Question 8

why is there an osmol gap

Answer 8

serum osmolality is increased by circulating alcohols and other low MW substances that arent calculated in osmolarity

Question 9

osmol gap =

Answer 9

measure osmolality - calculated osmolarity

Question 10

normal osmol gap

Answer 10

10+/- 6 mOsm

Question 11

how is ethanol eliminated

Answer 11

mostly enzymatic oxidation
unchanged
michaelis menten

Question 12

elimination in chronic drinkers

Answer 12

increased due to enzyme induction

Question 13

ethanol metabolism

Answer 13

first pass - ADH in gastric mucosa

liver - ADH, CYP2E1, peroxidase catalase, ALDH

Question 14

ethanol MOA

Answer 14

membrane fluididication
enhance GABAnergic function
inhibition and upregulation of NMDA receptors and increase in dopamine release

Question 15

what is functional tolerance

Answer 15

ppl metabolize alcohol better and can tolerate the CNS effects better so can tolerate higher doses

Question 16

lethal ethanol dose adult

Answer 16

5-6g/kg in nontolerant

Question 17

lethal ethanol dose child

Answer 17

3g/kg

Question 18

stages of acute intoxication

Answer 18

50mg/dL: mild 
100mg/dl: mild - mod 
200: moderate - NV
300: severe - hypotermia, hypoglycemia, seizure 
700: lethal - resp depression

Question 19

metabolic derangements

Answer 19

hypoglycemia
metabolic acidosos
hypomagnesemia

Question 20

explain ethanol induced hypoglycemia

Answer 20

hepatic glycogen is rapidly consumed
ethanol converted to acetate uses up NAD
increased lactate
thiamine deficiency impairs acetylcoA = more lactate

Question 21

explain alcoholic ketoacidosis

Answer 21

glycogen consumed free fatty acids are mobilized
acetylcoa formed from fatty acid oxidation
forms acetoacetate or goes to fatty acid synthesis

Question 22

management of intoxicated patient

Answer 22

glucose, oxygen, thiamine

Question 23

labs to ask for

Answer 23

alcohol levels
finger stick glucose level
electrolytes - magnesium
anion and osmol gap

Question 24

interventions

Answer 24

gastric lavage if massive ingestion
charcoal not efficient
hemodialysis

Question 25

signs of alcoholic liver disease

Answer 25

fatty liver alcoholic hepatitis alcoholic cirrhosis

Question 26

drug interactions in alcoholism

Answer 26

enzymatic induction results in increased clearance of phenytoin, methadone, tolbutamide, isoniazide, warfarin but... once at cirrhosis metabolism is impaired

Question 27

acute intoxication drug interactions

Answer 27

additive effects with antihistamines, barbiturates, and sedatives transient increase in plasma levels of other agents increased acetaminophen hepatotoxicity cimetidine increases levels antabuse reaction

Question 28

what is antabuse reaction

Answer 28

inhibitors of alcohol dehydrogenase causes accumulation of acetaldehyde tolbutamide, carbamates, metronidazole

Question 29

why does alcohol wihtdrawal occur

Answer 29

hbituation of the organism to the cns depressant effects - uncompensated state of overstimulation due to upregulation of NMDA receptors

Question 30

interventions for alcoholic patient

Answer 30

``` serotonin uptake inhibitors naltrexone campral bromocriptine lithium disulfiram ```

Question 31

absorption of methanol

Answer 31

rapid from oral route inhalation skin

Question 32

Vd of methanol

Answer 32

small, in the blood

Question 33

elimination of methanol

Answer 33

primarily liver zero order at high conc and first order at low unchanges in urine and by lungs

Question 34

methanol metabolized into

Answer 34

formaldehyde and formic acid | very toxic

Question 35

how is ethanol an antidote for methanol

Answer 35

affinity of ADH for ethanol is 4x greater than its affinity for methanol, prevent the metabolism into toxic metabolites

Question 36

formation of formic acid

Answer 36

conversion of formaldehyde to formic acid is rapid so there is no accumulation of formaldehyde

Question 37

metabolic effect of methanol

Answer 37

direct effect on metbaolic acidosis from formic acid and indirect effect due to lactate produciton, mitochondria toxicity, etc

Question 38

how does ocular toxicity occur

Answer 38

directly by formic acid acidosis increases toxicity by favoring diffusion inhibition of retinal and optic nerve mitochondrial function

Question 39

signs of ocular toxicity

Answer 39

blurred vision snow field vision fundoscopic exam shows hyperemia of the optic disc and retinal edema reduced pupillary response to light

Question 40

permanent ocular damage due to methanol

Answer 40

``` optic atrophy perpheral constriction of visual fields central scotoma reduced visual acuity loss of color vision blindness ```

Question 41

treatment of methanol od

Answer 41

``` supportive care correction of acidemia (sodium bicarb) fomepizole or ethanol iv folinic acid hemodialysis ```

Question 42

when would you use hemodialysis in methanol od

Answer 42

>25mg/dL | >7.8mmol/L

Question 43

methanol od levels we want to determine

Answer 43

evaluate acidosis osmol gap - check if all accounted for by ethanol ethanol and methanol levels anion gap

Question 44

action level for hemodialysis in ethylene glycol

Answer 44

>25mg/dL or >4.03mmol/L with acidosis or renal insufficiency

Question 45

fomepizole moa

Answer 45

competitive inhibitor of ADH

Question 46

fomepizole dosing

Answer 46

loading dose 15mg/kg 10mg/kg q12hr for 4 doses 15mg/kg q12hr

Question 47

treatment for ethylene glycol od

Answer 47

``` ethanol fomepizole thiamine and pyridoxine to min oxalic acid formation folates hemodialysis ```

Question 48

dose of thiamine and pyridoxine

Answer 48

100mg and 50mg iv every 6hr

Question 49

methanol change in osm

Answer 49

31

Question 50

ethanol change in osm

Answer 50

22

Question 51

isopropanol change in osm

Answer 51

17

Question 52

ethylene glycol change in osm

Answer 52

16

Question 53

acetone change in osm

Answer 53

18