Pharmacology - Test 2 Gen Anesth (Spring 11)

Front 1

True or False - General anesthesia usually requires only IV drugs

Back 1

False - General anesthesia usually requires inhaled and IV drugs

Front 2

What are the stages of general anesthesia? (4)

Back 2

analgesia
excitement
surgical anesthesia
medullary depression

Front 3

Which stage of general anesthesia is characterized by decreased awareness?

Back 3

stage 1 - analgesia, conscious sedation

Front 4

Which stage of general anesthesia is characterized by delirium, amnesia, enhanced reflexes, vomiting, incontinence, and irregular respiration?

Back 4

excitement

Front 5

Which stage of general anesthesia is characterized by unconsciousness, no pain reflex, normal BP and respiration?

Back 5

surgical anesthesia

Front 6

Which stage of anesthesia is characterized by severe respiratory and cardiovascular depression and requires circulatory and respiratory support?

Back 6

medullary depression

Front 7

What is the mechanism of action for general anesthetics?

Back 7

Increase opening of GABAa ligand-gated ion channels

Front 8

What is an alternative mechanism of action for general anesthetics?

Back 8

May activate ligand-gated potassium channels or inhibit nicotinic receptor cationic channels

Front 9

Which anesthetic appears to antagonize the NMDA (glutamate) receptor?

Back 9

Ketamine

Front 10

What is the major inhibitory neurotransmitter in the CNS?

Back 10

GABA

Front 11

How many pore-forming subunits are in a GABAa ion channel?

Back 11

5

Front 12

Which subunits bind anesthetic drugs? (2)

Back 12

alpha, beta

Front 13

Which anesthetic needs GABA present to open GABA receptors?

Back 13

benzodiazepines

Front 14

What are characteristics of stage 1 anesthesia? (2)

Back 14

analgesia, conscious sedation

Front 15

Which neurons are involved in stage 1 anesthesia?

Back 15

dorsal horn neurons

Front 16

Stage 1 anesthesia inhibits what type of information going to the brain? (2)

Back 16

pain, sensory

Front 17

Stage 2 anesthesia is (inhibitory/disinhibitory)

Back 17

disinhibitory

Front 18

What is characteristic of stage 3 anesthesia?

Back 18

muscle relaxation

Front 19

What pathway is affected in stage 3 anesthesia?

Back 19

ascending pathways of reticular activating system (sleep/wake cycle)

Front 20

What is characteristic of stage 4 anesthesia?

Back 20

cardio-respiratory collapse

Front 21

What part of the brain is affected in stage 4 anesthesia?

Back 21

vasomotor centers of medulla

Front 22

Which inhaled anesthetics have low blood solubility (faster CNS action)? (2)

Back 22

desflurane, nitrous oxide

Front 23

Which inhaled anesthetics have high blood solubility (slower CNS action)? (2)

Back 23

halothane, methoxyflurane

Front 24

As solubility of an inhaled anesthetic in the blood increases, its ability to penetrate the BBB and enter the CNS (increases/decreases)

Back 24

decreases
(high solubility = slow CNS action)

Front 25

What effect does ventilation rate have on the transfer of gas from the aleveoli to blood to brain?

Back 25

higher ventilation = higher uptake

Front 26

What effect do opioids have on inhaled anesthetics?

Back 26

slow uptake (opioids cause respiratory depression, and slower ventilation means slower uptake)

Front 27

What effect does pulmonary blood flow have on uptake of inhaled anesthetics from gas from the alveoli to blood to brain?

Back 27

higher blood flow = slower uptake
(more blood drug can be diffused in)

Front 28

What is the major route of elimination for inhaled anesthetics?

Back 28

lungs

Front 29

Insoluble drugs eliminate at a (fast/slow) rate

Back 29

fast

Front 30

True or False - There is no risk of accumulation for inhaled anesthetics

Back 30

False - soluble anesthetics may accumulate if given over a long period of time

Front 31

Which inhaled anesthetics can form hepatotoxic metabolites? (2)

Back 31

halothane, methoxyflurane

Front 32

Which inhaled anesthetics are the least metabolized? (2)

Back 32

isoflurane, desflurane

Front 33

Which inhaled anesthetic is not metabolized?

Back 33

nitrous oxide

Front 34

What is the median partial pressure that immobilizes 50% of patients when exposed to surgical stimulation?

Back 34

MAC (minimum alveolar anesthetic concentration)

Front 35

Most patients require how many MACs?

Back 35

0.5 - 1.5

Front 36

What happens to the MAC in the elderly and infants?

Back 36

it's lower

Front 37

What happens to the MAC when used with opioids or sedatives?

Back 37

it's lower

Front 38

Inhaled anesthetics have what effects on the cardiovascular system? (4 of 5)

Back 38

decrease mean arterial pressure, bradycardia via vagal stimulation, increase heart rate, myocardial depression, sensitize the myocardium to catecholamines

Front 39

Which inhaled anesthetics reduce cardiac output? (2)

Back 39

halothane, enflurane

Front 40

Which inhaled drugs decrease vascular resistance? (3)

Back 40

isoflurane, desflurane, sevoflurane

Front 41

Which inhaled drug causes bradycardia via vagal stimulation?

Back 41

halothane

Front 42

Which inhaled drugs cause increased heart rate? (2)

Back 42

desflurane, isoflurane

Front 43

Which inhaled drug sensitizes the myocardium to catecholamines?

Back 43

halothane

Front 44

Which inhaled drug can cause arrhythmias in patients taking catecholamines?

Back 44

halothane

Front 45

What effects to inhaled anesthetics have on respiratory volume and respiratory rate?

Back 45

decrease respiratory volume
increase respiratory rate

Front 46

True or False - All inhaled anesthetics are respiratory depressants

Back 46

True

Front 47

True or False - All inhaled anesthetics increase mucocilliary function

Back 47

False - all depress mucocilliary function

Front 48

Inhaled anesthetics cause (bronchodilation/bronchoconstriction)

Back 48

bronchodilation

Front 49

Which inhaled anesthetic can cause airway irritation (bronchospasm, coughing)?

Back 49

desflurane

Front 50

Which inhaled anesthetic is pungent (reduces breathing)?

Back 50

enflurane

Front 51

Which inhaled anesthetics cause bronchodilation and are useful in induction? (2)

Back 51

halothane, sevoflurane

Front 52

What effect do inhaled anesthetics have on cerebral blood flow?

Back 52

increase cerebral blood flow by decreasing cerebral vascular resistance

Front 53

Which inhaled anesthetics cause burst suppression of electroencephalogram (EEG)? (3)

Back 53

halothane, isoflurane, enflurane

Front 54

Which inhaled anesthetic may induce seizure-like activity on EEG?

Back 54

Enflurane

Front 55

Which inhaled anesthetic has high analgesic and low amnesiac activity?

Back 55

N2O

Front 56

What effects do inhaled anesthetics have on the kidneys? (3)

Back 56

increase renal vascular resistance
decrease renal blood flow
decrease GFR

Front 57

What effects do inhaled anesthetics have on hepatic blood flow?

Back 57

decrease hepatic blood flow

Front 58

What effects do inhaled anesthetics have on uterine smooth muscle?

Back 58

relax uterine smooth muscle

Front 59

Which inhaled anesthetic may inhibit renal function?

Back 59

enflurane

Front 60

What condition is caused by the combination of inhaled anesthetics given with muscle relaxants?

Back 60

malignant hyperthermia

Front 61

What mutation causes malignant hyperthermia?

Back 61

mutation in ryanadine receptors

Front 62

What are symptoms of malignant hyperthermia? (5)

Back 62

tachycardia, hypertension, muscle rigidity, hyperthermia, acid/base imbalance

Front 63

What is the mechanism of action of malignant hyperthermia?

Back 63

increases in free calcium concentration in skeletal muscle cells

Front 64

What is used to treat malignant hyperthermia?

Back 64

dantrolene (reduces Ca2+ release)

Front 65

What type of anemia may result from chronic exposure to N2O?

Back 65

megaloblastic anemia (decrease in methionine synthase)

Front 66

What are the barbiturate IV anesthetics? (2)

Back 66

thiopental, methohexital

Front 67

What is the mechanism of action of barbiturates?

Back 67

Increase DURATION of GABAa channel openings in response to GABA binding

Front 68

What is the mechanism of action of benzodiazepines?

Back 68

Increase FREQUENCY of GABAa channel openings in response to GABA binding

Front 69

True or False - Barbiturates can work without the presence of GABA

Back 69

True

Front 70

True or False - Benzodiazepines can work without the presence of GABA

Back 70

False - require GABA to work

Front 71

Which benzodiazepine is water-soluble?

Back 71

Midazolam

Front 72

Which benzodiazepines are not water-soluble?

Back 72

diazepam, lorazepam (require delivery in nonaqueous vesicles - irritating)

Front 73

Benzodiazepines have a (slower/faster) onset of action that barbiturates

Back 73

Slower

Front 74

True or False - Benzodiazepines can reach surgical levels alone

Back 74

False - part of a cocktail component

Front 75

What type of amnesia is produced by benzodiazepines?

Back 75

anterograde (sedation and amnesia)

Front 76

What antagonist is used to accelerate recovery form sedative effects of benzodiazepines?

Back 76

flumazenil

Front 77

What is the mechanism of action of propofol?

Back 77

directly activates GABAa channel opening

Front 78

Propofol has a (slow/rapid) onset of action and a (slow/rapid) recovery

Back 78

rapid onset of action
rapid recovery (faster than barbiturates)

Front 79

Which IV anesthetic has anti-emetic activity

Back 79

propofol

Front 80

True or False - Propofol is commonly used as a cocktail

Back 80

True

Front 81

True or False - In outpatient surgery, propofol is used as part of a cocktail

Back 81

False - can be used alone in outpatient surgery

Front 82

Propofol is used for prolonged sedation in patients in what type of care?

Back 82

critical care

Front 83

What are the adverse effects of propofol? (4)

Back 83

respiratory depression
decrease in systemic BP (hypotension)
cardiovascular effects (hypotension)
apnea, pain, and muscle movements

Front 84

What is the mechanism of action of etomidate?

Back 84

Directly activates GABAa channel opening

Front 85

What part of anesthesia is etomidate used for?

Back 85

induction

Front 86

Etomidate has a (slow/rapid) loss of consciousness and a (slow/rapid) recovery

Back 86

rapid loss of consciousness
rapid recovery

Front 87

What effect does etomidate have on the cardiovascular and respiratory systems?

Back 87

minimal cardiovascular and respiratory depression

Front 88

Where is propofol metabolized?

Back 88

liver

Front 89

Where is etomidate metabolized?

Back 89

liver

Front 90

What is an adverse effect associated with prolonged infusion of etomidate? (2)

Back 90

hypotension, electrolyte imbalance

Front 91

What is ketamine structurally similar to?

Back 91

PCP (phencyclidine)

Front 92

What is the mechanism of action of ketamine?

Back 92

Blocks excitatory NMDA (glutamate) receptors

Front 93

What type of amnesia does ketamine cause?

Back 93

dissociative - conscious, but no pain, movement, or memory

Front 94

What IV anesthetic causes dissociative amnesia? (conscious, but no pain, movement, or memory)

Back 94

ketamine

Front 95

What effect does ketamine have on the cardiovascular system?

Back 95

increases HR, BP, and CO through SNS activation

Front 96

What effect does ketamine have on intracranial pressure?

Back 96

increases cerebral blood flow (not for use in patients with elevated intracranial pressure)

Front 97

What effect does ketamine have on respiration?

Back 97

decreases respiratory rate

Front 98

Which IV anesthetic has hallucinogenic effects post-operatively?

Back 98

ketamine

Front 99

What specific patient populations is it okay to use ketamine in? (2)

Back 99

elderly (because of low cardiovascular activity)
children (low sensitivity to psychic effects)

Front 100

What are the IV anesthetic opioids? (5)

Back 100

morphine, fentanyl, sufentanil, remifentanil, alfentanil

Front 101

Morphine and fentanyl are usually given with what anesthetics? (2)

Back 101

N2O, benzodiazepines

Front 102

N2O and benzodiazepines are usually given with what opioids? (2)

Back 102

morphine, fentanyl

Front 103

Which opioids are used as induction agents? (2)

Back 103

alfentanil, remifentanil

Front 104

Which opioid is used in ambulatory procedures because of its short duration of action?

Back 104

remifentanil

Front 105

Which faster onset drugs are often used for induction? (3)

Back 105

thiopental, propofol, etomidate

Front 106

Maintain anesthesia with (IV/inhaled) anesthetics

Back 106

inhaled (N2O, desflurane)