23. Anesthetics

Question 1

Propofol.
Metabolism
Effects
VD
1/2 life
EEG

Answer 1

Effect. Decrease CO, increase peak effect. Suppress SVT.
Lusotropic

CYP3A4 inh. No muscle relaxation.
Peak effect 90-100
VD 2-10 l

EHL 4-7 h

EEG. Increase alpha, after shift to teta, gamma. More than 8 microg/kg Burst suppression

Question 2

Ketamine

Answer 2

Causes emergence reaction
Increase PVR.
Activates in biphasic mode
Increase salivation
No respiratory depression

Question 3

Etomidate

Answer 3

Decrease CBF 34%
Decrease CMR 45%
CPP the same
ICP decrease
Has the lowest context sensitive half time
Causes adrenal depression though 11 hydrohyburate
Independent risk factor for delirium
No effect in convulsions

Question 4

Dexmedetomidine

Answer 4

Metabolized by gluconization
Works on G protein
half-life 2-3 h
Context-sensitive half-life high
Analgesic effect thought the spinal cord
Works on locus caeruleus for hypnosis

Question 5

Fospropofol metabolism

Answer 5

Degraded in plasma

Question 6

Barbiturates

Answer 6

Alkaline. No mix with ringers or acidic solutions
Preserve CPP
Neuroprotectors (for partial cerebral ischemia)
Mixed only with Ketamine
Patients awake after 5-10 of a single dose of thiopental

Question 7

Drug of choice for electroconvulsive therapy

Answer 7

Methohexital

Question 8

MDZ and PONV

Answer 8

Gives protection vs PONV

Question 9

Elimination of propofol

Answer 9

Most hepatic. Second kidney

Question 10

PharmacoK of lorazepam

Answer 10

Little altered by age, no by renal disease or gender.
Clearance is decrease with liver dysfunction

Question 11

Emergence reation with ketamine

Answer 11

Incidence in pediatrics like older age
Affected by age, gender (more common in women), dose, and drugs.
More concentrated and faster incidence

Question 12

Highest and lowest half-life, clearance, and volume of distribution of commonly used anesthetics

Answer 12

DZP. Longest half-life, lowest Cl
Propofol and Dex highest clearance
Propofol highest VoD

Question 13

Context sensitive half-time of common anesthetics

Answer 13

Doctors Treat Many Illnesses
DZP
Thiopental
Midazolam
Induction agents (K-P-E)

Question 14

Propofol. MoA

Answer 14

GABA beta in the brain, alpha if high concentration.
Inhibition of NMDA

Question 15

Uses and Doses of intravenous Propofol

Answer 15

Induction of general
anesthesia 1-2.5 mg/kg IV, dose reduced with increasing age

Maintenance of general
anesthesia 50-150 μg/kg/min IV combined with N2O or an opiate

Sedation 25-75 μg/kg/min IV

Antiemetic action 10-20 mg IV, can repeat every 5-10 min or start infusion of 10 kg/kg/min

Question 16

Flumazenil
Dosage

Answer 16

0.2 - 3.0 mg
If a patient shows no signs of recurrent sedation within 2 hours after a 1-mg reversal dose of flumazenil, serious recurrent sedation at a later time is unlikely