Chapter 15: Inhalation Sedation: Techniques of Administration

Question 1

three phases of the nitrous sedation technique

Answer 1

1) the induction phase (steps 1 to 4)
2) the injection and treatment phase (step 5)
3) the recovery phase (steps 6 and 7)

Question 2

day of the appointment: monitoring during inhalation sedation. the following is the recommended monitoring for inhalation sedation procedures:

Answer 2

1) baseline vital signs, preoperatively
2) verbal communication with the patient
3) vital signs recorded periodically during the procedure
4) postoperative vital signs

Question 3

preparation of the patient (3 steps)

Answer 3

1) request that the patient visit the restroom and void if necessary before the start of the sedative procedure
2) review the medical history questionnaire and record preoperative vital signs before the start of the N2O-O2
3) if the patient wears contact lenses, they should be removed

Question 4

the technique of administration of N2O

Answer 4

1) position the patient in a comfortable, reclined position in the dental chair
2) position the inhalation sedation unit
3) start the flow of O2 at 6L/min, place the nasal hood over the patient’s nose, and remind the patient to breathe through the nose
4) secure the nasal hood
5) determine proper flow rate for the patient
6) observe the reservoir bag
7) begin titration of N2O
8) observe the patient
9) continue titration of N2O
10) observe the patient
11) begin dental treatment
12) observe the patient and inhalation sedation unit during the procedure
13) terminate the flow of N2O
14) discharge the patient
15) record data concerning the sedation procedure
16) cleanse the equipment

Question 5

what is the proper flow rate for an adult at the onset of a procedure?

Answer 5

6-L/min of 100% O2

Question 6

what is the proper flow rate for a smaller pediatric patient at the onset of a procedure?

Answer 6

3 or 4 L/min for smaller pediatric patients

Question 7

what kind of patients might require a larger minute volume?

Answer 7

petite patients, patients participating in endurance sports, marathon running, swimming, bicycle racing. additionally patients with COPD, Heart Failure, or partial nasal obstruction

Question 8

a bag that remains totally deflated indicates one of the following things:

Answer 8

• the minute volume of gas is inadequate, in this situation, the patient will usually complain of not receiving enough “air”
• the nasal hood has relatively large leaks; in this case the patient will have no difficulty breathing because any lack of gas from the N2O-O2 unit is compensated for by ambient air entering through the leaks.

Question 9

a bag that is overly inflated looking like a balloon about to burst may indicate one of the following things:

Answer 9

• minute volume is too great for the patient; although an unlikely occurrence, the patient might complain about an inability to breathe against the rapid flow of air into the nasal hood
• the hoses leading from the sedation unit have become kinked (occluded). in this case patient will complain about an inability to breathe comfortably through the nasal hood

Question 10

which is more likely to occur involving an overly inflated bag? the hoses leading from the sedation unit becoming kinked or occluded or the minute volume being too great for the patient?

Answer 10

occluded tubes is more likely to occur

Question 11

what is the constant liter flow technique?

Answer 11

the total liter flow of gases per minute is kept constant throughout the procedure

Question 12

what is the constant O2 flow techinque?

Answer 12

the liter flow of O2 remains constant and the volume of N2O is adjusted

Question 13

what are three clinical sensations that usually indicate that the patient is approaching the desired level?

Answer 13

heaviness, warmth, and floating

Question 14

what is “white knuckle” syndrome ?

Answer 14

patients who are apprehensive and do not appear comfortable will have their hands firmly clenching the armrest and their legs will seem quite stiff. as the sedation develops the patient’s arms and legs relax, and he or she eventually will achieve a “sedated look”

Question 15

what should you do if the patient has movements that are significant or disruptive?

Answer 15

halt the procedure and increase the level of sedation of N2O by 5%

Question 16

what is the percentage of placebo response for most drugs?

Answer 16

there is a 15-20% positive placebo response for most drugs, and if approached carefully this response may be used to advantage in many N2O-O2 patients

Question 17

what are the factors used in evaluating the recovery phase?

Answer 17

• response of the patient to questioning
• vital signs
• a test for motor coordination

Question 18

what are vital signs indicative of?

Answer 18

objective parameters that indicate the state of function of the patient’s cardiorespiratory system (BP, HR, RR)

Question 19

fluctuations in either direction are normal. parameters that may be useful in determing the degree of recovery following sedation are the following for BP, HR and RR

Answer 19

BP: +/- 20 mm Hg/10 mm Hg from baseline
HR and rhythm: +/- 15 beats/minute from baseline; same rhythm as baseline
RR: +/- breaths/minute from baseline

Question 20

what is a Trieger test?

Answer 20

an objective measurement of the patient’s ability to perform fine motor movements. the adaptation for this test for measuring recovery from anesthesia and sedation is based on the fact that fatigue and CNS depressant drugs exaggerate psychomotor dysfunction.

two factors: 1) time required for the patient to complete the test of connecting the dots (10 seconds). 2) the general quality of the lines (i.e., straight, wavy, or erratic)

Question 21

explain the current recommended procedure for sterilization of nasal hoods

Answer 21

• after each use, the nasal hood is washed with soap and warm water and then immersed in glutaraldehyde solution for 10 minutes.
• it is then rinsed thoroughly with tap water to remove the disinfectant solution
• at the end of each week, all tubing, reservoir bags, and nasal hoods are stored in glutaraldehyde for 10 hours to achieve complete sterilization.
• after this 10 hour period, the equipment is rinsed in warm tap water for 1 hour

Question 22

advantages of constant liter flow technique

Answer 22

1) smaller volumes of gases used
2) less costly
3) decrease in exhaled N2O contamination

Question 23

disadvantage of constant liter flow technique

Answer 23

percentage increments of N2O are fixed; thus it is easier to oversedate the patient

Question 24

advantages of constant O2 flow technique

Answer 24

• slightly easier to use, requires adjustment of one dial
• larger volumes of gases used; thus little difficulty in breathing adequately
• percentage increments of N2O decrease as the percentage of N2O increases (see charts), minimizing risk of inadvertent oversedation

Question 25

disadvantage of constant O2 flow technique

Answer 25

• larger volumes of gases used; thus more costly to administer
• larger volumes of N2O used; thus potentially greater contamination of environment with N2O

Question 26

clinical indicators of oversedation

Answer 26

1) patient persistently closes the mouth
2) patient begins spontaneously mouth breathing
3) patient complains of nausea and effects of sedation felt as too intense or uncomfortable
4) patient fails to respond rationally or gives sluggish responses
5) patient begins to lose control
6) patient speaks incoherently or dreams
7) patient becomes uncooperative
8) patient laughs, cries, or becomes giddy
9) patient has uncoordinated movements

Question 27

what is one of the earliest signs of oversedation?

Answer 27

patient persistently closes the mouth

Question 28

Objectives of nitrous oxide/oxygen inhalation sedation (6 things)

Answer 28

1. Reduce or eliminate anxiety
2. Reduce untoward movement and negative reaction to dental tx
3. Enhance communication and patient cooperation
4. Raise the pain reaction threshold
5. Increase tolerance for longer appointments
6. Reduce gagging