Nitrous ALL

Question 1

Describe mild sedation?

Answer 1

less than 50% N2O concentrations and not covered in guidelines

Question 2

What is moderate sedation?

Answer 2

> 50%

Question 3

What is the range of N20 we use?

Answer 3

No more than 70% N2O, no less than 30% O2

Question 4

What does N2O act upon?

Answer 4

Opioid receptors or activate the release of endogenous opiates

Question 5

Describe deep sedation/analgesia?

Answer 5

depression of consciousness, not easily aroused but respond purposefully after repeated or painful stimulation.

Question 6

Describe general anesthesia?

Answer 6

• LOSS of consciousness
• NOT arousable
• may need positive pressure ventilation.

NOT an N20 thing

Question 7

Does N2O cross the alveolar membrane easily?

Answer 7

yes

Question 8

Is N2O very soluble or insoluble?

Answer 8

insoluble, which means it has a faster onset action

Question 9

describe the concentration effect:

Answer 9

this is what happens with high concentrations (not low, causing negative pressure and draws more gas into lungs, increasing volume)

Question 10

Describe the second gas effect?

Answer 10

rapid uptake of N2O allows a second gas to be drawn in much faster as well so common to pair N2O up with more potent anesthetic agents

Question 11

how is N2O elated?

Answer 11

lungs

Question 12

T/F

N2O is the most potent inhalation GA?

Answer 12

LEAST.

potency is determined by the MAC

Question 13

what is the MAC?

Answer 13

amount of drug to prevent mvmt in 50% OF INDIVIDUALS.

SO

Question 14

What is the MAC N2O?

Answer 14

104-105% meaning it cannot along produce profound surgical anesthesia

SO this aids in the safety of N2O

Question 15

Who regulates N2O gas?

Answer 15

FDA

Question 16

N2O/O2 is driven by what?

Answer 16

the O2 flow. That’s what you should monitor!

Question 17

What indicates the amount of gas being delivered?

Answer 17

flowmeter. This corresponds to L per minute and has a failsafe mechanism. If O2 drops below 30%, the N2O stops.

Question 18

What is the purpose of the reservoir bag?

Answer 18

provides additional gas if the patient inspires more than is being supplied (usually holds 3L of gas)

• provides a mechanism for monitoring pt respiration
• provides emergency method for positive pressure O2

Question 19

T/F

Nasal hoods should have scavenging capabilities?

Answer 19

TRUE

Question 20

what is the average tidal volume?

Answer 20

500 mL

Question 21

what is the minute ventilation?

Answer 21

the tidal volume * rate of respiration. Usually around 6-7 mL

This will tell you the amount of gas mixture to give!

Question 22

What is the anatomic dead space?

Answer 22

portion of the inhaled air that does not enter the lungs

Question 23

what causes diffusion hyposia?

Answer 23

N2O exists faster than N2 which dilutes O2 and reduces the amount of O2 saturation

Question 24

What is the Cardiovascular effect of N2O?

Answer 24

No effect on the CV… may actually help myocaridal ischemia because it provides supplemental O2. Helpful in MI!

BP and HR are usually not affected but may lower due to relaxation

Question 25

What the the effect on respiratory system?

Answer 25

increases the pressure in the sinuses. For minimum sedation, ventilation is not depressed. Chronically debilitating respiratory conditions are relative contraindication

Question 26

why do you have to be aware of vitamin B12 deficiency?

Answer 26

interferes with B12 dependent enzymes

Question 27

Why might GI be an issue?

Answer 27

if patient has bowel obstruction could cause problems because the gas is expansive

Question 28

Does N2O cross the placental barrier?

Answer 28

yes

Question 29

what is the cancer contraindication?

Answer 29

DON”T use if patient is on bleomycin sulfate therapy

Question 30

what is the minute ventilation for children?

Answer 30

4-5 L