Inhalation Anesthesia 3 Flashcards

(50 cards)

1
Q

What happens to MAP with increases in concentration of des/iso/sevo in dose dependent manner?

A

MAP decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What effects does N2O have on BP?

A

Unchanged or even mildly increased MAP.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What effect does halothane have on MAP and CO?

A

Decreases MAP by decreasing CO.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Isoflurane, a linear dose dependent increase in HR after what MAC?

A

0.25 MAC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are HR effects of sevoflurane?

A

HR does not increase until concentrations >1.5MAC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the studied effects of desflurane on HR?

A

Min increase in HR <1 MAC.

At >1MAC, linear dose dependent increase in HR is observed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the more clinical experiences with desflurane on HR?

A

When you overpressurize you will see some significant tachycardia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the calculation to determine if tachycardia will be seen with desflurane adminsitration?

A

If percent concentration multiplied by gas flow is greater than 24, you will see tachycardia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the changes seen in cardiac index with inhalation agents?

A

Minimally influences by inhalation agents.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What effect do inhaled agents have on dysrhythmogenicity (other than halothane)?

A

Inhaled agents do not predispose the heart to PVCs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What effect do inhaled agents have on QT interval?

A

All prolong QT interval, but sevoflurane should be avoided with congenital long QT syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is coronary steal?

A

Isoflurane’s ability to dilate small diameter coronary arteries might cause a susceptible patient to develop regional myocardial ischemia as a result of coronary vasodilation.
(not found valid).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is ischemic preconditioning?

A

Helps protect the heart by insulting the heart just a little. Gets preconditioned by minor insult then protects the heart from larger ischemic event.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

There are two distinct periods of protection, what are they?

A

First period-
-1-2 hrs after conditioning
Second Period-
- Reappears 24hrs later and can last up to 3 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What chemically happens that protects the heart in ischemic preconditioning?

A

Opening of mitchondrial ATP sensitive K+ATP channels.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Without the presence of other agents, what effect do inhalation agents have on RR and TV?

A

Increased RR and decreased TV.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens to MV with inhalation agents?

A

Stays about the same (>RR,

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What happens to chemoreceptors?

A

Blunted response of central chemoreceptors. May have to get 45-50 before start breathing again.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which stimulation response is strong: hypoxia or hypercarbia?

A

Hypoxia, we just don’t use it.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which agent is “nicest to breathe”?

A

Sevoflurane, halothane, N2O.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What agents are worst to breath (pungent)?

A

Desflurane and isoflurane.

22
Q

What patients should you be cautious using a pungent anesthetics like des and iso?

A

Asthma, reactive airway disease, COPD, smokers

23
Q

Which inhalation agents causes increases in CMRO2?

24
Q

What changes in CNS effects can be seen around (above or below) 1 MAC?

A

ICP increases with all anesthetics at > 1 MAC.
Autoregulation is impaired at concentrations 1 < MAC.
Evoked potentials may be abolished at 1 MAC.

25
Though 0.2-0.3 MAC can decrease the reliability of motor evoked potentials, what other medication actually has a bigger effect?
NMBA
26
Which inhalation agent will we not use in patients with seizure history?
Sevoflurane
27
At what MAC might you see isoelectric EEG pattern?
1.5-2.0 MAC
28
true or false. | Inhalation agents have limited effect on the principle of hypoxic pulmonary vasocontriction?
True
29
Which agent would you avoid in head trauma/intracranial processes?
N2O
30
Which medication can counteract the negative effects of N2O in intracranial processes?
Barbs, opiods, or propofol
31
What happens to autoregulation <1 MAC?
It is impaired
32
What MAC do Hamot surgeons allow for checking evoked potentials?
1 MAC
33
True or false: | Inhalation agents produce a dose dependent skeletal muscle relaxation and enhance the activity of NMBA?
True. | Can also be helpful on emergence. As gas comes off, NMBA effects will decrease.
34
Which agents trigger MH?
Halothane>Forane (isoflurane),>Sevoflurane>Desflurane
35
Which agents have hepatic effects/injury?
Halothane>sevoflurane>desflurane=iso=enflurane
36
Renal effects are seen with what agent?
Sevoflurane
37
What is produced from the breakdown of sevoflurane?
Compound A.
38
What does the package insert say about sevo administration and renal effects?
If FGF <2L/min, must keep MAC fas flow to max of 2 hrs.
39
Which agent is contraindicated in pneumothorax?
N2O
40
Which deficiency would contraindicate N2O?
B12 Deficiency
41
What is the blood:gas coefficient of the anesthetic gases?
``` N2O=0.47 Des=0.45 Sevo=0.65 Iso=1.4 Halo=2.3 ```
42
When an air filled cavity has a compliant wall, what increases with N2O administration?
Volume
43
When an air filled cavity has a non-compliant wall, what increases with N2O administration?
Pressure
44
Degradation of CO2 Absorbent creates an exothermic or endothermic process?
Exothermic process (releases heat)
45
Which agent has a specifically high production of compound A?
Sevoflurane
46
What complications can arise from iso and des administration with a dessicated absorbent?
Can produce Carbon Monoxide
47
What actions can prevent exothermic reactions or excess compound A production?
``` PREVENTION: Adequate hydration is key. -change CO2 absorbent often. -Turn FGF down or off during breaks. -Limit FGF during cases. -When in doubt, change it. ```
48
What is the vapor pressure of des at sea level and 20 degrees C?
700mmHg
49
TEC 6 vaporizer heats desflurane to how many ATM?
2 ATM
50
Formula to calculate for changes in altitude?
(Desired vaporizer setting at sea level) x (760mmHg) / (Current ATM)