Benzodiazepines

Question 1

Benzos act on which GABA subunits?

Answer 1

between alpha and gamma

Question 2

GABA alpha 1 causes

Answer 2

sedation, amnesia, anticonvulsant

Question 3

GABA alpha 1 found in

Answer 3

cerebral cortex, cerebellar cortex, thalamus

Question 4

GABA alpha 2 causes

Answer 4

anxiolytic, skeletal muscle relaxation

Question 5

GABA alpha 2 found in

Answer 5

hippocampus, amygdala

Question 6

Besides benzos what else binds on GABA?

Answer 6

barbituates, etomidate, propofol, alcohol

causes risk of OD d/t synergistic effects

Question 7

Midazolam IV onset

Answer 7

1-2 minutes

Question 8

Midazolam IV peak effect

Answer 8

5 minutes

Question 9

Midazolam IV E 1/2 time

Answer 9

2 hours

doubled in elderly patients…hepatic flow/enzyme activity

Question 10

Midazolam IV Volume of distribution

Answer 10

1-1.5 L/kg (large)

increased in elderly and obese

Question 11

Midazolam metabolized by

Answer 11

CYP3A4

Question 12

active metabolite of midazolam

Answer 12

1-hydroxymidazolam

1/2 activity of parent

Question 13

Drugs that cause inhibition of P-450 enzymes

Answer 13

-Cimetidine
-Erythromycin
-CCB
-Antifungal
-FENTANYL

Question 14

Midazolam CNS effects

Answer 14

-decreases CMRO2
-Decreases CBF
-does not produce isoelectric EEG
-anticonvulsant
-Preserves vasomotor response to CO2
-No change in ICP

Question 15

Midazolam pulmonary effects

Answer 15

-decreases ventilation (dose dependent)
-depresses swallowing reflex
-decreases upper airway activity

Question 16

Midazolam CV effects

Answer 16

-Increased HR
-Decreased BP
-No CO change
-SVR decreased
-Enhanced hypotension with hypovolemia

Question 17

Midazolam pediatric sedation oral dose & peak

Answer 17

0.25-0.5 mg/kg

peak: 20-30 min

Question 18

Midazolam adult sedation dose & peak

Answer 18

1-5 mg IV

peak: 5 min

elderly require smaller dose

Question 19

Midazolam induction dose

Answer 19

0.1-0.2 mg/kg over 30-60 seconds

facilitated by 50-100mcg of fentanyl 1-3 min before

Question 20

Midazolam post-op sedation dose

Answer 20

1-7 mg/hr

Question 21

Diazepam onset

Answer 21

1-5 minutes

Question 22

Diazepam E 1/2 time

Answer 22

20-40 hours

Question 23

Diazepam metabolized by

Answer 23

CYP3A4

Question 24

Diazepam active metabolite

Answer 24

Desmethyldiazepam (48-96 hours) and oxazepam

Question 25

Diazepam CNS effects

Answer 25

-Decreases CMRO2 -Decreases CBF -Potent anticonvulsant -can produce isoelectric EEG

Question 26

Diazepam pulmonary effects

Answer 26

-minimal effects on ventilation

Question 27

Diazepam CVS effects

Answer 27

-minimal BP, CO, and SVR changes

Question 28

Diazepam neuromuscular effects

Answer 28

-decreases tonic effect on spinal neurons -SKM tone decreased

Question 29

Diazepam induction dose

Answer 29

0.5-1.0 mg/kg

Question 30

Lorazepam peak effect

Answer 30

20-30 minutes

Question 31

Lorazepam E 1/2 time

Answer 31

14 hours

Question 32

Lorazepam dosing

Answer 32

1-4 mg single dose

Question 33

Flumazenil dosing

Answer 33

0.2 m; titrated to consciousness -repeat 0.1 mg q 1 min to 1 mg total

Question 34

Reversal dose

Answer 34

0.3-0.6 mg to reverse sedation 0.5-1.0 mg to abolish therapeutic dose