Lecture #15 - Drugs and Surgery

Question 1

First anesthetics?

Answer 1

Diethyl ether

Question 2

Diethyl ether was replaced by? in 1956

Answer 2

Halothane, because

Question 3

General anesthesia induce in patients?

Answer 3

Loss of consciousness/sensation
Amnesia
Relaxation of skeletal musc.
Autonomic and endocrine reflexes are then suppressed

Question 4

Premedication aims at ?

Answer 4

reduce anxiety, pain, salivation

Question 5

2 steps of general anesthesia: Induction goal

Second step?

Answer 5

1-Induce unconsciousness very quickly

2-maintains unconsciousness: volatile agent/gases

Question 6

Inhalation anesthetics all en in?
Barbiturates often end in?
Benzo?

Answer 6

ane
al
am

Question 7

IV tend to have… structure and volatile agents … structure.

Answer 7

ring - not ring

Question 8

Pharmakokinetics of Inhalation Anesthesia two major components and their subcompanents?

Answer 8

1-Partial pressure of the gas

2-Blood flow: If high CO, less relative go to brain so reduce induction

Question 9

If gas dissolved in blood does it still contribute to the gas partial pressure?

Answer 9

No

Question 10

Is nitrous oxide a gas? Why better then all the other?

Answer 10

No, volatile liquid.

Because it doesn’t decrease blood pressure/respiration

Question 11

Factors influencing rate of induction (4)?

Answer 11

1-Higher the {} in inspired gas the faster the induction
2-Higher ventilation = faster indution
3-GREATER THE SOLUBILITY OF GAS IN BLOOD, THE SLOWER THE INDUCTION RATE, BECAUSE LESS DRUG ENTERS THE BRAIN AND STAYS IN THE BLOOD.
4-High CO = lower relative {}to brain

Question 12

MAC?

Answer 12

Minimal Alveolar Concentration = ED50. 1.3MAC is the gold standard

Question 13

Respiratory depression caused by?

Answer 13

Increasing CO2 level in blood

Question 14

Inhalationnal have musc. relaxant effect? Does NO have one?

Answer 14

Yes, no.

Question 15

Metabolization of Inhalationnal?

Answer 15

1-2%, the rest is exhaled. Except halothane 15% met.

Question 16

Halothane compatible with epinephrine?

Answer 16

NO

Question 17

Inhalationnal cause vomitting?

Answer 17

Yes by triggering CTZ.

Question 18

Can NO cause complete general anes.?

Answer 18

No, because would need to be 100%, but you need to give O2 at the same time.

Question 19

Isoflurane/Sevoflurane sensitize the heart?

Answer 19

No, compatible with EPI

Question 20

Generally IV have…. cardiovascular/respiratory depressive effects?

Answer 20

less

Question 21

IV pharmakokinetics?

Answer 21

Lipid soluble, effect is fast with short duration of action

Question 22

Do IV have a wider margin of safety?

Answer 22

YES

Question 23

Onset of action of thiopental? Distribution?

Answer 23

30 seconds, distributed throughout the body

Question 24

Midazolam advantage over diazepam? Danger?

Answer 24

Faster action. Accumulate in the body

Question 25

Conscious sedation?

Answer 25

Opioid + MIdazolam

Question 26

Opiod resp. depression caused by?

Answer 26

Inability to respond to higher CO2 blood level

Question 27

1-"Neurolept" analgesia? and 2-anesthesia?

Answer 27

1-Fentanyl + antipsychotic | 2-With NO

Question 28

Only IV that stimulates Cardio?

Answer 28

Ketamine

Question 29

Antagonize nausea?

Answer 29

Ondansteron - 5HT blocker

Question 30

Pharmakodynamics of general anesthetics?

Answer 30

1) Decrease transmitter release at presynaptic terminal 2) Decrease responsivness at post-synaptic 3) Extra-synaptically at pre-synaptic side affecting Ca+ release 4) Extra-synaptically at post-synaptic side affecting tonic inhibition.

Question 31

Except for ketamine and NO all IV?

Answer 31

Increase GABA inhibition

Question 32

Ketamine action?

Answer 32

decrease glutamate at NMDA receptor, blocking excitation

Question 33

Musc. blocking agents (2)?

Answer 33

1- Competitive blocking: Curare derivative, (ium). Compete with acetylcholine 2- Succinylcholine: Activate receptor and keep receptor desensitized.

Question 34

Succinylcholine danger?

Answer 34

Indi. deficient in pseudocholinesterase, they cannot breakdown the drug. They will stop breathing.

Question 35

Local analgesia mec. of action?

Answer 35

Act on voltage gated Na+ channel. = stop spreading of action-potential

Question 36

Local analgesia often given with adrenaline b/c?

Answer 36

Reduce blood flow -> reduce plasma cholinesterase which metabolizes them (also liver meta. them)

Question 37

Derivative of cocaine, sometime used for?

Answer 37

Cardiac arrythmias

Question 38

two cat. of local anes.?

Answer 38

Ester and amides (amide = longer half-life)

Question 39

EMLA?

Answer 39

Eutectic mixture of local anesthetics