9-Nitrous Oxide Pt. 1

Question 1

what is the most costly part of the inhalation route?

Answer 1

the initial set up/equipment

Question 2

T/F the inhalation route is the safest route

Answer 2

true

Question 3

with the inhalation route _________ is easy but quickly reversed

Answer 3

overdose

Question 4

what are the objectives of conscious sedation?

Answer 4

1. Reduce fear and apprehension
2. Obtain patient cooperation
3. Avoid loss of consciousness
4. Maintain vital signs within normal limits

Question 5

what pt’s are good candidates for N2O?

Answer 5

Patients who are emotionally stable and cooperative but are apprehensive about undergoing dental treatment

Question 6

what pt’s are bad candidates for N2O?

Answer 6

Some patients react poorly emotionally usually obsessive/compulsive or claustrophobic

Strange mental affect and/or mentally handicapped patients sometimes have less satisfactory sedation

Question 7

what are the colors for the tanks (in the US)

Answer 7

Nitrous oxide: blue
oxygen: green

Question 8

what are the different types of tanks for Nitrous Oxide?

Answer 8

G (giant) (13839 L) 750 psi
E-economy (1590 L) 750 psi

Question 9

what are the different types of tanks for Oxygen?

Answer 9

H-(huge)cylinder (6900 L)2000 psi
E-cylinder (660 L) 2000 psi

Question 10

T/F with Nitrous oxide the pressure is not an accurate indicator of the amount of gas whereas the oxygen pressure is accurate for the amount of gas present

Answer 10

true
-nitrous oxide stays at 750 psi until liquid has evaporated
-shows pressure decrease when tank hits ~20% full

Question 11

with the older demand flow machines you were able to give ________% nitrous oxide while the modern ones can only give _______%

Answer 11

100%, 80%

Question 12

with the continuous flow N2O machine how is the machine monitored?

Answer 12

by gauges in liters/minute

Question 13

with the continuous flow N2O machine you can’t give less than _______% oxygen

Answer 13

30%

Question 14

what is the porter triple outlet station?

Answer 14

for the continuous flow N2O machine
white = vac
green = O2
blue = N2O

Question 15

what does the bag tree outlet do?

Answer 15

Connects to flowmeter
Connects to reservoir bag
Connects to fresh gas tubing

Question 16

when was the fail-safe O2 mechanism added to the continuous flow N2O machine?

Answer 16

mid-1970’s

Question 17

what does the fail-safe O2 mechanism do for the continuous flow N2O machine?

Answer 17

if O2 runs out, nitrous drops to zero flow

said this will be on the exam

Question 18

how often should the flowmeter be calibrated on the continuous flow N2O machine?

Answer 18

every 2 years

Question 19

how can you tell where the measurement is on the flowmeter on the continuous flow N2O machine?

Answer 19

middle of the ball will indicate L/min

Question 20

scavenging systems prevent problems at approximately _______ L/min to minimize leakage of N2O for the continuous flow N2O machine

Answer 20

45

Question 21

reservoir bag should be about _______ full for N2O for the continuous flow N2O machine

Answer 21

2/3

Question 22

what are the 3 purposes of the reservoir bag for the continuous flow N2O machine?

Answer 22

1. Source of additional gas should pt inspire more gas than is supplied through the hoses (Capacity approx 3 liters)
2. Monitors pt’s respirations – expand/contract (No exhaled air goes into bag - scavenged)
3. In an emergency can deliver positive pressure
   (Not with a nasal hood
   Need full mask/good seal)

Question 23

T/F the nasal hood is made of latex and so you need to be careful with those who have allergies

Answer 23

false

Question 24

T/F only certain nasal hoods will have scavenging capability

Answer 24

False all have it

Question 25

T/F scavenging system is the Standard of care

Answer 25

true

Question 26

if doing IV sedation the nasal hood must also have what?

Answer 26

capnography capability (all IV sedation needs this)
-monitoring exhaled by CO2

Question 27

what are the safety factors of the continuous N2O flow machine?

Answer 27

Fail-Safe
Designed to deliver ≥ 30% oxygen
Pin indexing system
Diameter of attachment couplings (hose attachment)
Reservoir bag

Question 28

how do you prepare the pt for the continuous flow N2O machine

Answer 28

First check nitrous machine/connections, then
Seat patient
RMH, confirm surgical site(s), informed consent,
Place monitors
Select correct size of nasal hood
Place patient in supine/semi-spine position
Place/adjust nasal hood

Question 29

begin and end with _______% O2 when using the continuous flow N2O machine

Answer 29

100%

Question 30

T/F do not leave sedated pt alone at any point

Answer 30

true

Question 31

for the nitrous technique you should divide the nitrous flow by the ________

Answer 31

total gas flow

Question 32

what’s a general ratio for O2 to N2O?

Answer 32

3:1

Question 33

what should you encourage your pt to refrain from doing to get full benefit from the N2O?

Answer 33

talking

Question 34

what are the adverse effects of N2O?

Answer 34

Nausea/Vomiting
Dysphoria
Headache
Excessive sweating

Question 35

why do you continue O2 flow for at least 5 min?

Answer 35

Minimizes diffusion hypoxia

Question 36

what is diffusion hypoxia?

Answer 36

When administration of nitrous is stopped, large volumes of nitrous oxide diffuse from the blood into the lung alveoli, diluting oxygen – a temporary reduction in the amount of alveolar oxygen

Question 37

T/F a N2O pt needs an escort to drive them home

Answer 37

false
you already know this