Conscious sedation technique for impacted tooth removal

1. PRESENTED BY-
AVANTHIKA SASANKAN
FIRST YEAR

2.  HISTORY
 INTRODUCTION
 DEFINITIONS
 AIMS & OBJECTIVES OF CONSCIOUS
SEDATION
 PREREQUISITIES FOR SEDATION
 INDICATIONS & CONTRAINDICATIONS

3.  PATIENT ASSESSMENT & PREPARATION
 LEVELS OF SEDATION & GA
 DRUGS USED FOR CONSCIOUS SEDATION
 AAP / AAPD GUIDELINES
 CONCLUSION

4.  To perform the highest quality dental care in
patients, the practitioner may need to use
pharmacologic means to obtain a quiet, cooperative
patient.
 Techniques that use drugs to induce a cooperative yet
conscious state in an otherwise uncooperative patients
are most commonly referred to as techniques of
conscious sedation.

5. CONSCIOUS SEDATION-
A minimally depressed level of
consciousness, that retains the patient’s ability
to maintain an airway independently &
respond appropriately to physical stimulation
& verbal commands.
(AMERICAN DENTAL ASSOCIATION,1993)

6. CONSCIOUS SEDATION (Old Terminology)-
Now called as MODERATE SEDATION
Moderate Sedation-Analgesia: A drug-induced
depression of consciousness during which patients respond
purposefully to verbal commands, either alone or
accompanied by light tactile stimulation.
This includes—
 Airway is patent, & spontaneous ventilation is adequate.
 Cardiovascular function is usually maintained.
 Reflex withdrawal from a painful stimulus is not considered
a purposeful response.
(AAP/AAPD GUIDELINES,2006)

7. ANXIOLYSIS (old terminology)
Now called as MINIMAL SEDATION
A drug-induced state during which patients
respond normally to verbal commands.
 Cognitive function & coordination may be impaired.
 Ventilatory and cardiovascular functions are
unaffected.
(AAP/AAPD Guidelines 2006)

8. DEEP SEDATION-
A drug induced depression of
consciousness during which patients cannot be
easily aroused but respond purposefully after
repeated verbal or painful stimulation.
(AAP/AAPD Guidelines 2006)
The ability to independently maintain ventilatory
function, may be impaired.
 Patients may require assistance in maintaining a
patent airway.
 Cardiovascular function is usually maintained.
 A state of deep sedation may be accompanied by
partial or complete loss of protective airway reflexes.

9. GENERAL ANESTHESIA-
A controlled state of unconsciousness,
accompanied by partial or complete loss of
protective reflexes, including inability to
maintain an airway independently & respond
purposefully to physical stimulation or verbal
command.
(AMERICAN DENTAL ASSOCIATION,1993)

10. 1. Guard the patient’s safety and welfare
2. Minimize physical discomfort and pain
3. Control anxiety, minimize psychological trauma
4. Maximize the potential for amnesia
5. Control behavior and movement to allow the safe
completion of the procedure
6. Return the patient to a state in which safe discharge
from medical supervision, as determined by
recognized criteria.(AAP 2006)
These goals can best be achieved by selecting the lowest
dose of drug with the highest therapeutic index for
the procedure.

11. 1. The practitioner should have knowledge of the
agents to be used & should be trained for their
administration.
2. There should be a well-documented informed
consent by patient who has had a consultation
on the alternatives & risks.
3. There should be no lack of equipment to
complicate the management of an emergency.

12.  There should be carefully planned rationale
for use of sedation which is based on-
 behavior of patient,
 nature & extent of treatment required,
 risk-to-benefit ratio,
 capability of family to meet the demands of an
extensive treatment plan &
 the economic feasibility.
 Mobile emergency medical services should be
readily available.

13. 1. Patients who cannot cooperate &
understand for definitive treatment.
2. Patient lacking cooperation because of
lack of psychological or emotional
maturity
3. Patients with dental care requirements,
but are fearful & anxious.

14. 1. Chronic obstructive pulmonary disease
(COPD), epilepsy, & bleeding disorders.
2. Uncooperative or unwilling patients.
3. Unaccompanied patients..
4. Prolonged surgery.
5. Lack of equipment or inadequate personnel.

15. 1. Obtaining patient history & information.
2. Informed consent from the accompanying
parent/ guardian.
3. Instructions to parents preop & postop.
4. Adequate documentation of the sedation
experience with monitoring of vital signs.

16. 1. OBTAINING PATIENT HISTORY ANDINFORMATION-
a) Information exchanged through a formal
interview helps in assessment of patient pain &
anxiety.
b) M/H specific to Sedation-
a) Abnormalities of major organ systems.
b) Previous adverse experience with sedation / GA.
c) Drug allergies & current medications.
d) Age in years & months & weight in kgs.
e) Time & nature of last oral intake.

17.  Only patients who are categorized into ASA
class I are routinely acceptable as candidates
for conscious sedation.
 Patients assigned to ASA classes II & III may
actually benefit from this approach, but this
must be determined in consultation with the
physician.
 Generally, patients categorized into classes III
& IV are better managed in a hospital setting.

18. 2. INFORMEDCONSENT- patient must be
agreeable to the use of conscious
sedation
 They should receive complete
information regarding--
 Risks &
 Benefits associated with the particular
technique.
 Agents being used.
 Alternative methods , if available.

19. 3. INSTRUCTIONS
 This information should include a 24-hour
contact number for the practitioner.
 Dietary instructions are as follows:
1. No solids for 6-8 hours
2. Clear liquids upto 3 hours before the procedure

20. Reasons for the instructions
Emesis during / after a sedative procedure is a
potential complication that can result in
aspiration of stomach contents leading to
laryngospasm or severe airway obstruction.
1. Aspiration may even lead to aspiration
pneumonia.
2. If the drug is taken by oral route, its uptake is
maximized when the stomach is empty.

21. 4. ADEQUQTE DOCUMENTATION OF SEDATIONEXPERIENCE-
 Intraoperatively vital signs should be recorded.
 Type of drug, dose given, route, site, and time
of administration should be noted.
 After completion of treatment, the patient be
observed in a well-equipped recovery area. The
patient should remain under direct observation
until respiratory and cardiovascular stability
have been ensured.

22.  GASES
 ANTIHISTAMINES
 BENZODIAZEPINES & ITS ANTAGONIST
 SEDATIVE HYPNOTICS
 NARCOTICS & ITS ANTAGONIST

23.  Gases used most commonly in Conscious
Sedation techniques– Nitrous Oxide (N2O) &
Oxygen(O2).
 85% of dentists use Nitrous oxide & oxygen for
sedation of patients. This makes it the most
frequently used sedative agent.

24. Physical / Chemical properties of N2O:
 Nitrous oxide (MW 44 & Sp gravity 1.53) is a slightly
sweet-smelling, colourless, inert gas.
 Boiling point is 88.5°C (127°F), indicates it is gas at room
temperature.
 When compressed in cylinder it becomes liquid &
vaporizes on release.
 It is nonflammable but, supports combustion.
Physical / Chemical Properties of O2:
 O2 (MW 32 & Sp gravity 1.1) is a odorless, colorless &
tasteless gas.
 It also supports combustion, but is nonflammable.

25. DESIRABLE CHARACTERSTICS OF N2O/O2
SEDATION:
1. Analgesic Properties (Pain Control)- 20%
N2O & 80% O2 has the same effect as 15mg
of Morphine. Has the ability to manage both
pain & fear (fear of an injection).
2. Amnestic properties- Postoperatively
patients are unable to recall the severity of
their pain or anxiety or its duration.

26. 3. Anxiolytic properties (sedative effects)- Assist
patients in handling their fear of anxiety by
producing sedation or a sense of well-being.
Facilitates positive behavior.
4. Onset of Action- Rapid less than 30 seconds,
peak effects in less than 5 minutes.
4. Recovery- Inhalation of N2O/O2 allows for
complete recovery with 100% pure oxygen for 5
minutes after termination of drug.

27. 4. Elimination- It is 99% eliminated from the
body within 5-10 minutes after discontinuation
of use.
4. Acceptance- Patient acceptance rate is same for
oral surgical procedures as it is for general
dentistry.

28. COMBINING N2O/O2 SEDATION WITH
OTHER METHODS:
1. Combination with Audio-analgesia. Since
music is a method for relaxing, distracting (also
known as “white sound”).
2. Oral premedication with Diazepam &
Meperidine.
3. N2O/O2 & Local anesthesia because together
offer superior pain & anxiety management
option.

29. PHARMACOKINETICS OF N2O:
 It has a blood-gas partition coefficient of 0.47
i.e. difference between partial pressures of gas
(N2O) & liquid (blood) indicates how quickly
agent crosses the pulmonary membrane &
enters the blood stream.
 It is an insoluble drug & remains unchanged in
blood & does not combine with any blood
elements.

30.  Since N2O does not break down, so peak
clinical effects may be seen within 3-5 minutes.
 There is no biotransformation & 99% of gas is
rapidly eliminated by the lungs. Very small
amounts may be found excreted in body fluids
and intestinal gas.

31. PHARMACODYNAMICS OF N2O:
 It produces nonspecific CNS depression.
Although classed with inhalational GAs, it
produces limited analgesia, & thus surgical
anesthesia is unlikely unless concentrations
producing anoxia are reached.
 So, O2 is given along with it, because its sole
purpose is to avoid anoxia.
 To minimize the effect, the patient should be
oxygenated for 3-5 minutes after a sedation
procedure.

32.  At concentrations 30-50%, N2O will produce a relaxed &
dissociated patient who is easily susceptible to suggestion.
Amnesia, but there is little alteration of learning or memory.
 Moderate sedation is achieved when N2O concentration is
50% .
 At concentrations greater than 60%, patients may experience
discoordination, ataxia, giddiness, and increased sleepiness.
 Concentrations greater than 50% are not to be used in dental
practice.
 The gas is nonirritating to the respiratory tract and can be
given to patients with asthma without fear of bronchospasm.

33. ADVERSE EFFECTS AND TOXICITY-
 Nausea and vomiting are the most common adverse effect
experienced with N2O sedation. Increases with more than 50%
conc or lengthy procedures.
 Middle ear pressure can increase pain in patients with acute
otitis media. It gets entrapped in gas-filled spaces such as the
middle ear, sinuses, and GIT.
 Neurotoxicity, impotence, and renal/liver toxicity.
 The greatest concern regarding toxicity centres on exposure of
dental personnel to high ambient air levels of the gas during its
use for patient sedation (i.e. longer than 3 hours per week

34.  Second gas effect : When N2O is being given
at 70-80% concentration initially, though it has
low solubility in blood, about 1l/min of N2O
enters blood in first few minutes higher than
minute volume.
 So, if another anesthetic is given at same time
,it will be delivered to the blood at same rate
i.e. 1l/min which is higher than minute volume
& induction effect will be faster, called as
SECOND GAS EFFECT.

35.  DIFFUSION HYPOXIA- Reverse occurs when
N2O is discontinued after prolonged
anesthesia. Since N2O has low blood solubility
it rapidly diffuses into alveoli & dilutes O2 in
alveoli (due to PP of O2 in alveoli is reduced),
thus O2- CO2 exchange is disrupted & a period
of hypoxia is created.
 This can be prevented by continuing 100% O2
for 5 minutes at termination of procedure.
 Diffusion hypoxia is not significant with other
anesthetic agents because they are given at low
conc (0.2-0.4) & are not able to dilute alveolar
air.

36. EQUIPMENT:
 The machine should be of the continuous-flow
design, with flowmeters capable of accurate
regulation.
 A fail-safe mechanism that provides automatic
shutdown if O2 falls below 25% and audible
and visual alarms that are activated.
 There should be a flush lever for easy and
immediate flushing of the system with 100%
oxygen.

37.  Efficient “SCAVENGER SYSTEM” is an
important component of any hose-mask
system. The double mask type is the most
efficient type of scavenger. These systems
exhaust into the vacuum waste system, which
is vented to the outside.
 Nasal hoods should be of good design & be
available in pediatric & adult sizes both.

38. Schematic diagram to show
components of a N2O/O2
delivery & scavenging
system

39. TECHNIQUE- After a
thorough inspection of
the equipment, the
mask should be
introduced to the
patient with an
explanation, and then
the mask should be
carefully placed over
the nose. A-Poorly fitting mask with leakage under
nares.
B-Well -fitting mask.

40.  The delivery tubes are tightened behind the
chair back in a comfortable position.
 Bag is filled with 100% oxygen and delivered
to the patient for 2/3 minutes at an appropriate
flow rate of 5-6 L /minute.
 With an appropriate flow rate, slight
movement of the mixing bag should be
apparent with each inhalation and exhalation.
 Too high flow rate, the bag will be
overinflated, movement will not be seen with
each breath.

41.  Too low flow rate will deplete the bag of
mixed gases.
 Once the proper flow rate is achieved, the N2O
can be introduced by slowly increasing the
concentration at increments of 10% to 20% to
achieve the desired level.
 The operator should encourage the patient to
breathe through the nose with the mouth
closed.

42.  SENSATIONS- Felt are floating, giddy feeling
with tingling of digits. The eyes will take on a
distant gaze with sagging eyelids.
 When this state is reached, the local anesthetic
may be given. Once this is completed, the
concentration can be reduced to 30% nitrous
oxide and 70% oxygen or lower. The patient
can now be maintained and monitored &
procedure carried out.

43.  The dentist should communicate with the
patient throughout the procedure, paying
particular attention to the maintenance of an
open, relaxed airway.
 An emesis basin should be readily available,
and if vomiting does occur, the head should be
rotated to the side.
 However, the laryngeal reflex is not obtunded
with nitrous oxide, and so aspiration of
vomitus is unlikely.

44.  Recovery can be achieved quickly by reverse
titration. Once the sedation is reversed, the
patient should be allowed to breathe 100%
oxygen for 3-5 minutes.
 The patient should be allowed to sit. Even
though psychomotor effects return to normal
within 5 to 15 minutes, it is not advisable to
allow teenage patients to drive themselves.

45. Guidelines on Appropriate Use of Nitrous
Oxide for Pediatric Dental Patients:
1. Must be given by licensed individuals only.
2. Informed consent of patients & documented in
patients record before administration.
3. Preoperative & postoperative vital sign values
are to be recorded.
4. Select the nasal hood according to the size of
individual & make sure it fits snugly. This can
decrease patient anxiety & increase trust.

46. 5. Determine flow rate of each person, 5-6 L/min
is acceptable for most patients.
6. Titration of N2O in intervals is recommended
for children because they exhibit signs &
symptoms of sedation so it important to
remember to allow time between increments so
drug can reach its peak effect before adding
more, this will reduce oversedation.
7. During treatment visual monitoring of the
patient’s respiratory rate & level of
consciousness.

47. 8. Pulse oximeter used when high concentrations
of N2O are used.
9. Once the N2O flow is terminated, 100% O2
should be delivered for a minimum of 5
minutes.
10.Patient should return to pretreatment
responsiveness before he/she is dismissed.
(AAP / AAPD GUIDELINES, 2006)

48. SUCTION FUNCTIONING SUCTION APPARATUS
OXYGEN ADEQUATE OXYGEN SUPPLY & FLOWMETERS
TO ALLOW ITS DELIVERY
AIRWAY APPROPRIATE AIRWAY (ENDOTRACHEAL
TUBES, FACE MASK)
PHARMACY ALL BASIC DRUDS NEEDED TO SUPPORT LIFE
DURING AN EMERGENCY
MONITORS FUNCTIONING PULSE OXIMETER
EQUIPMENT SPECIAL EQUIPMENT OR DRUGS FOR A
PARTICULAR CASE (E.G. DEFIBRILLATOR)

49. Conscious Sedation that is carefully
planned and carried out by a thoughtful, well-
trained health care team will allow both
caregivers and patients to have a positive
experience rather than a bad memory…