Anesthesiology

Question 1

What is the mechanism of most IV and inhaled anesthetics?

Answer 1

Most facilitate inhibitory GABAergic neurotransmission by keeping Cl- channels open, and augment inhibitory glycinergic function.

Question 2

Which two anesthetics have a different mechanism, and what is that mechanism?

Answer 2

Ketamine and Nitrous Oxide. These act by inhibiting excitatory glutamatergic channels (they block NMDA receptors, Nitrous Oxide also blocks kainate receptors)

Question 3

Name the inhaled anesthetics.

Answer 3

SHINE DM

Sevoflurane, Halothane, Isoflurane, Nitrous Oxide, Enflurane, Desflurane, Methoxyflurane

Question 4

What is the most commonly used inhaled anesthetic in the U.S.?

Answer 4

Isoflurane

Question 5

Which inhaled anesthetics have low solubility (fast induction)?

Answer 5

Nitrous Oxide, Isoflurane, Sevoflurane, and Desflurane

*SIND- send them to sleep fast

Question 6

Which inhaled anesthetics have a high solubility (slow induction)?

Answer 6

Enflurane, Methoxyflurane, Halothane

*MEH- meh, they’ll fall asleep eventually

Question 7

Which inhaled anesthetics are almost never used?

Answer 7

Halothane and Methoxyflurane

Question 8

What are the side effects associated with Nitrous Oxide?

Answer 8

Hypoxia upon discontinuation, can cause expansion of closed air spaces since it exchanges with N2

*don’t use w/ obstructed middle ear, air embolus, bowel obstruction, intraocular air bubble, or intracranial air

Question 9

What are the side effects associated with Enflurane?

Answer 9

CV depression 2/2 decreased contractility, seizures, and uterine muscle relaxation.

Question 10

Explain the relationship between anesthetics and GABA.

Answer 10

When GABA channels are kept open by the binding of anesthetics, it results in a much smaller voltage change when Na+ enters the neuron thus making excitation and depolarization more difficult and serving kind of like a buffer.

Question 11

What side effects are associated with Isoflurane?

Answer 11

Progressive respiratory depression

Question 12

What side effects are associated with Sevoflurane?

Answer 12

Reports of toxicity

Question 13

What side effects are associated with Desflurane?

Answer 13

Irritating to the airways (cough-provoking, salivation, bronchospasm), evokes tachycardia, low volatility

Question 14

What side effects are associated with Methoxyflurane?

Answer 14

Extensive metabolism and can produce renal failure and nephrotoxicity

Question 15

What side effects are associated with Halothane?

Answer 15

Respiratory depression, hypotension 2/2 myocardial depression, bradycardia, transient arrhythmias, hepatitis (immune response)

Question 16

Name the IV anesthetics.

Answer 16

Barbiturates (Sodium Thiopental), Propofol, Etomidate, and Ketamine

Question 17

Which IV anesthetic does not cause respiratory depression?

Answer 17

Ketamine

Question 18

Which IV anesthetic also provides analgesia?

Answer 18

Ketamine

Question 19

Which IV anesthetic causes hallucinations, increased muscle tone, and incidence of involuntary movement?

Answer 19

Ketamine

*these effects are less common in children

Question 20

What is pancuronium?

Answer 20

A muscle relaxant used to facilitate intubation.

Question 21

Which pre-anesthetic medications induce amnesia?

Answer 21

Benzodiazepines (Midazolam, Diazepam) and Antimuscarinics (Scopolamine, Atropine)

Question 22

Name the antiemetic often used to prevent aspiration.

Answer 22

Ondansetron (aka Zofran)

Question 23

What can be given with anesthetics to provide analgesia?

Answer 23

Opioids (Fentanyl, Morphine)

Question 24

What is used to prevent allergic reactions and provide some sedation?

Answer 24

Antihistamines (Diphenhydramine)