Benzodiazepines (Test 1) Flashcards
Sedatives:
a drug that induces calm or sleep
Hypnotics:
a drug that induces hypnosis or sleep
What are the commonalities between sleep and anesthesia?
Commonalities in the reticular activating system and CNS
Inhibits thalmic and mid-brain RAS
Reversibly inhibit CNS
How is unconsciousness measured?
Range of how deeply unconscious you are
When did EEG monitoring come about?
1937 EEG could be used to measure effects
1952 depth of anesthesia correlates with concentration of ether
What do electroencephalograms measure?
Continuous monitoring of cerebral function
Locations are related to location of the brain
Impractical to put these into the OR
What does BIS monitor stand for?
Bispectral Analysis: condensed processed EEG
1996
What is the BIS monitor used for?
Gage depth of anesthesia
Rapid change in BIS correlated with increase awareness
What level of BIS is the patient unconscious?
BIS <58
What level of BIS is associated with longer time to wake up?
<65
BIS change with hypnotic drugs:
BIS change correlated to patient movement
BIS changes with high dose narcotics:
Less correlation between BIS and movement
What is on all BIS monitors?
Signal quality Index (SQI)
EMG (no movement when paralyzed unless paralytic has worn off)
EEG (processed signals)
Suppression Rate (SR)–never has a number
What does a BIS of 0 mean vs a BIS of 100?
0= dead
100= aware
What is the ideal BIS to range for no recall?
40-60
What are some synergistic effects that also reduce BIS readings?
GABA effect, Muscle relaxers
What sedative medication can make BIS look higher?
Ketamine (sympathomimetic)–increases brain activity
What meds can make BIS more depressed?
Beta blockers
Volatile anesthetics
Narcotics
What is the main thing we use the BIS for?
Trending
What are the pharmacologic effects of benzodiazepines?
Anxiolytics-helpful to chronic anxiety
Sedation
Anterograde Amnesia-lasts longer than sedative effects
Anticonvulsant actions-valium
Spinal-cord mediated skeletal muscle relaxation
What is the only thing that can cause retrograde amnesia?
Electro convulsant therapy
How do Benzos compared to barbiturates?
-Less tolerance
-Less potential for abuse
-Fewer and less serious SE
-Do not induce hepatic enzymes
Benzos have replaces bariturates for preop sedation
How are all benzos similar?
Structurally similar
Same antagonist
What is the most common used benzo in perioperative period?
Midazolam–quick on quick off