General Anesthetics Flashcards Preview

Pharmacology Block 3 > General Anesthetics > Flashcards

Flashcards in General Anesthetics Deck (35):
1

Sodium thiopental mechanism of action (3):

-GABAa activator.
-Decreases cerebral oxygen utilization, blood flow, and intracranial pressure.
-Drop in BP because of vasodilation (reduction in preload).

2

Sodium thiopental uses:

-Induces anesthesia.
-Has been tried as a protective agent against cerebral ischemia.

3

Sodium thiopental side effects:

**Produces hypotension, hangover effect.
-Respiratory depression

4

Propofol mechanism of action (3):

-GABAa activator.
-Results in a decrease in cerebral oxygen utilization, blood flow, and intracranial pressure.
-Drop in BP because of vasodilation (reduction in preload), AND depression of myocardial contractility.

5

Propofol uses:

-Induces and maintains anesthesia.
-Antiemetic.
-Has a shorter half-life than thiopental; used when a rapid return to normal mental status is desired.

6

Propofol side effects:

-Hypotension and respiratory depression (more than thiopental).
-Pain at injection site.
-Can produce excitation during induction.

7

Etomidate mechanism of action:

Activates GABAa receptors through allosteric effects.

8

Etomidate use:

Primarily used to induce anesthesia in patients at risk for hypotension (less CV effects than thiopental and propofol).

9

Etomidate side effects:

-Significant nausea and vomiting.
-Increased post-surgical mortality due to suppression of the adrenocortical stress-response.

10

Ketamine use:

-Reserved for patients with bronchospasm, and children undergoing short, painful procedures.

11

Ketamine mechanism of action:

-NMDA receptor antagonist.
-Produces a hypnotic state called “dissociative anesthesia”, characterized by profound analgesia, unresponsiveness to commands (even though eyes can be open), amnesia, spontaneous respiration, *bronchodilation.

12

Ketamine side effects:

-Emergence delirium.
-Nystagmus, salivation, lacrimation, spontaneous limb movements, and increased muscle tone.
-Increased BP due to indirect sympathomimetic activity.

13

Midazolam mechanism of action:

-Short acting benzodiazepine.
-GABAa activator. Metabolized by hydroxylation to an active metabolite.

14

Midazolam use:

- Used for conscious sedation during minor surgical procedures (wisdom teeth extraction).
- Slower induction time and longer duration than thiopental.

15

Midazolam side effects:

-Respiratory arrest.
-Use with caution in patients with movement disorders, bipolar disorder.

16

Isoflurane mechanism of action:

Inhaled GABAa activator with moderate blood:gas partition coefficient.

17

Isoflurane uses:

- Used to induce and maintain anesthesia.
- Co-administration with NO allows for reduction in the dose.

18

Isoflurane side effects:

- Airway irritant.
- Respiratory depressant, increases PaCO2.
- Myocardial depression. Arrhythmias (sensitizes the heart to catecholamines).
- Dilates cerebral blood vessels, increasing intracranial pressure. Dilates coronary vessels.

19

Desflurane mechanism of action:

-Inhaled GABAa activator with low blood:gas partition coefficient (rapid induction and recovery).
-Produces direct skeletal muscle relaxation.

20

Desflurane uses:

-Used for maintenance of general anesthesia in outpatient surgeries.

21

Desflurane side effects:

- Airway irritant - causes coughing and bronchospasms.
- Respiratory depressant, increases PaCO2.
- Myocardial depression. Arrhythmias (sensitizes the heart to catecholamines).
- Dilates cerebral blood vessels, increasing intracranial pressure. Dilates coronary vessels.

22

Sevoflurane mechanism of action:

-Inhaled GABAa activator with low blood:gas partition coefficient (rapid induction and recovery).

23

Sevoflurane uses:

-Used for maintenance of general anesthesia in inpatient and outpatient surgeries.
-Little irritation to airways.

24

Sevoflurane side effects:

-Less irritation to airways, less respiratory depression.
-Myocardial depression.

25

Nitrous oxide uses:

- Often co-administered with other inhalational anesthetics; rapid uptake from the alveolae results in increased concentration of the second anesthetic.
- Co-administration also allows for a reduction in dosage.
- Results dilutional hypoxia: place patients on 100% O2.
- Used in outpatient dentistry.

26

Nitrous oxide contraindication:

Contraindicated in pneumothorax: can exchange with nitrogen in any air-containing cavity.

27

Cocaine mechanism of action:

-Exhibits local anesthetic activity and also blocks NE uptake into presynaptic adrenergic nerves (potent vasoconstrictor).

28

Cocaine uses:

- Used in ENT surgery to provide anesthesia and limitation of bleeding.

29

Tetracaine use:

- Widely used in spinal anesthesia and in topical ophthalmic preparations.
-Rarely used for peripheral nerve block (need a large dose).

30

Benzocaine use:

-Topical anesthetic.

31

Lidocaine mechanism of action:

Produces fast, intense, long-lasting anesthesia. Use with EPI to decrease absorption.

32

Lidocaine use:

- Used in almost any application where a local anesthetic of IM duration is needed.

33

Bupivacaine use:

-Produces long-lasting anesthesia.
-Sensory block (more so than motor block).

34

Bupivacaine side effects:

More cardiotoxicity than equal doses of lidocaine (dissociates from Na+ channels slowly, resulting in increased potency for blocking cardiac conduction).

35

Ropivacaine use:

-Comparable to the S-enantiomer of Bupivacaine (less cardiotoxic effects). Suitable for epidural and regional anesthesia. Even more motor sparing.