IH sedation M11 Flashcards
What reasons would inhalation sedation not be successful?
If the patient has cold or can not breath properly on the day.
What is the minimum amount of oxygen a patient will receive at all times during IH sedation?
30%
What is the maximum amount of Nitrous oxide a patient will receive at one time?
70%
Can the depth of sedation be controlled during IH sedation?
Yes
How long does it take for the patient to feel the initial effect of nitrous oxide?
after 20 seconds
How long does it take for the patient to feel the full effect of nitrous oxide?
3-5 minutes
Does nitrous oxide provide some analgesia effect?
Yes
Nitrous oxide is delivered to the patient via which method?
Via nasal mask, which is inhaled through the respiratory system
Where does the nitrous oxide is inhaled, where does it travel to?
Alveoli sacs within the lungs
What takes place when the nitrous oxide arrives in the lungs?
Gaseous exchange
What is gaseous exchange?
Oxygen moving into the blood and carbon dioxide moves into the lungs
When Nitrous oxide is introduced to the body, how does it get into the blood?
It diffuses through the alveolar membrane into the blood
How is nitrous oxide eliminated by the body?
99% exhalation straight away & 1% through through skin and lungs over the next 24 hours
Why are patients given 100% oxygen at the end of IH treatment?
to prevent diffusion hypoxia
How long is 100% oxygen given to a patient at the end of treatment
3-5 minutes
What is second gas effect?
When nitrous oxide stops it is eliminated from the body very quickly. The level of carbon dioxide in the blood is greatly reduced.
A breath is taken to expel the rising level of carbon dioxide, if this level is reduced the patient will not be able to breath.
When the RA machine is turned off, nitrous oxide in the blood will enter the lungs very quickly in large amounts, what does this do to the oxygen levels in the lungs and what could happen?
Dilutes the oxygen in lungs and can cause hypoxia, headaches and nausea
What is stage 1 in anaesthesia?
The induction stage
The time between first administration and loss of consciousness
What is stage 1 plane 1 in IH sedation?
Moderate sedation & analgesia
How much nitrous oxide is administered in stage 1 plane 1 in IH sedation?
5%-25%
What is stage 1 plane 2 in IH sedation?
Disassociation sedation & analgesia
How much nitrous oxide is administered in stage 1 plane 2 in IH sedation?
20%-55%
What is stage 1 plan 3 in IH sedation?
Total amnesia
How much nitrous oxide is administered in stage 1 plane 3 in IH sedation?
50%-70%
If the patient is unable to keep their mouth open during treatment, how much would the nitrous oxide be reduced?
10%
When the oxygen is set at 100% where will the mental ball on the oxygen flow meter be at?
8L/min
When the oxygen is at 50% and the nitrous oxide is at 50% where will the metal ball in the oxygen flow meter be at?
4L/min
If the delivery of oxygen were to stop, what would happen to the nitrous oxide flow.
It will automatically be cut off, by the nitrous oxide cut-off valve.
If the patient received pure nitrous oxide, what would happen?
could result in patient death
What does the scavenging system do?
Allows the nitrous oxide in the atmosphere to be removed
What does the air entrainment valve do?
Allow the patient to breath the atmospheric area if both gases shut off
What does the reservoir bag allow the dentist/nurse to do?
monitor respiration of the patient
How does the IH machine ensure the patient does not enter stage 2 of anaesthesia?
by providing 30% oxygen at all times and a maximum of 70% nitrous oxide
If you pressed the ‘flush’ button, what would happen ?
extra oxygen would be provided
How many oxygen cylinders and nitrous oxide cylinders should be present at all times, and how are these labelled?
x4
x2 oxygen / x2 nitrous oxide
Labelled in use & full
What colour is the oxygen cylinder?
Black with a white collar & white pipe
What colour is the nitrous oxide cylinder?
Blue & blue pipe
What is the Bodok seal?
it provides a seal between the cylinder and machine to prevent leakage
If you tap the gas cylinder and it has a duller sound, what does this mean?
less gas it contains
‘E’ cylinders have what safety feature?
unique pin indexing, which makes it impossible for the wrong cylinder to be connected
What is the oxygen flow rate for an adult?
8L/min
What is the oxygen flow rate for a child?
6L/min
Once the patient is settled, what mixture of gases is given to the patient?
85% oxygen & 15% nitrous oxide
When increments of nitrous oxide are given to the patient
5% at a time, until 30%
How long does the patient need to stay after IH sedation?
20-30 minutes
What is the pressure of an oxygen cyclinder?
2000psi
When was nitrous oxide produced?
1772
When did it begin to be used in medical professions?
1844
What is the pressure of a nitrous oxide cylinder?
800psi
What is WELS?
Workplace Exposure Limits
Who sets WELS?
The health and safety commission
The long-term exposure to nitrous oxide is weighted at what?
100ppm over an 8-hour period in any 24 hours
What control measures should be in place when working with nitrous oxide?
Staff notation
Nasal mask correctly fitted
High volume aspiration
Rubber dam
