CONSULTANT

DEPARTMENT OF

ANESTHESIOLOGY &

INTENSIVE CARE

PUBLIC HOSPITAL

AUTHORITY’S

RAND MEMORIAL HOSPITAL

FREEPORT,

THE BAHAMAS

DR. MRIDUL M. PANDITRAO

DENTAL CHAIR ANAESTHESIA

PROS & CONS

The association between anaesthesia and dentistry:

Horace Wells (Dec. 1844): N2O; Failed Demo. WTG Morton: “Inventor of Anaesthesia” GQ Colton: Reintroduced N2O

Thereafter for almost 100 years GA was a norm for Dental procedures Decline in popularity of General AnaesthesiaLocal Analgesia and Sedation emerged as a choice for Outpatient Dental Anaesthesia

INTRODUCTION

Although low Mortality (1 in 226000-300000)1,2

Mortality or morbidity in a young fit patient coming for a brief and trivial procedures is a major concernAnaesthesia is conducted by an unqualified person (the surgeon himself or a non-Anaesthetist) in a poorly equipped setup

INTRODUCTION (Cont)

1. Coplans MP, Curson I. Deaths associated with dentistry. British Dental Journal 1982; 153: 357-62.2. Tomlin P. Deaths associated with dentistry, British dental anaesthetic practice. Anaesthesia. 1974; 29: 551-70.

Efforts to address these ethical, moral & economical issues: The Poswillo Report (1990)3 , Department of Health, UK This was revised in 19984 and amended again in 19995 and from USA in 19996

INTRODUCTION (Cont)

3.Poswillo D. General Anaesthesia, sedation and resuscitation in dentistry: Report of an expert working party. London: Department of Health, 1990.

4.General Dental council. General Dental council: Maintaining standards: Guidance to dentists on professional and personal conduct: Amendments: General Anaesthesia and Resuscitation. London: General Dental council, 1998.

5.General Dental council. General Dental council: Maintaining standards: Guidance to dentists on professional and personal conduct: Amendments: Pain & Anxiety control. London: General Dental council, 1999.

6.Silker ES. Office based anaesthesia (ASA OBA Guidelines- ASA Guidelines- ASA House of delegates): New Orleans: 1999.

Aims & Objectives (Goals of learning)

Understanding basic fundamentals

Getting to know available guidelines

Actual existing circumstances in India & our own

experience

Recommendations

I. Out patient Dentistry includes: Conservative dentistrySingle or multiple simple tooth extractionImpacted Molar ExtractionSimple, short duration orthognathic proceduresIncision and drainage, ennucleation of cyst/other soft tissue surgeries of short duration

Understanding Basics fundamentals

II.Indications of outpatient dental anaesthesia include:

ChildrenAnxious/apprehensive patients Mentally retardedPatients with allergic to local Anaesthetics or failure of L A

Understanding Basics fundamentals (Cont)

III. Sedation for outpatient dentistry:Conscious sedation is a carefully

controlled technique in which a single intravenous drug or combination of oxygen and nitrous oxide is used to reinforce hypnotic suggestion and reassurance in a way which allows dental treatment to be performed with minimal physiological and psychological stress, but allows verbal contact with patients to be maintained at all times

Understanding Basics fundamentals (Cont)

Indications for Sedation:

Patients with simple, genuine fear or phobia of dental treatment Young uncooperative childrenPatients with mild systemic disorders i.e. controlled hypertension, angina or asthma.Patients with neuromuscular disorders, i.e. Spasticity, Parkinsonism

Contraindications:

Only ASA I & II are fit for Sedation Contraindicated in:

Significant Cardio-Respiratory DiseaseNeuromuscular weaknessSevere psychiatric disorderPregnancy/ LactationUn-cooperative, unwilling, unaccompanied patientsProlonged dental proceduresInexperienced Dentist/ AssistantLack of appropriate equipmental resources

Relative Analgesia (Langer 1976)7

Concept – to divide 1st stage of Guidel’s Classification into 3 planes:1st & 2nd plane - Relative Analgesia3rd plane - Complete Analgesia

15 – 30 % Nitrous Oxide → 1st plane30 – 55 % Nitrous Oxide → 2nd plane55 % + Nitrous Oxide → 3rd plane

7.Launger H. Relative Analgesia in dental practice; WB Saunders. Philadelphia: 1076.

In 1st plane there is moderate sedation and analgesia.

In 2nd plane sedation is dissociative

with greater element of Analgesia.

In 3rd plane there is total analgesia preceding loss of consciousness.

Local analgesics should be used along

with nitrous oxide

Inadequate nasal breathingImproper fitting of mask due to facial abnormalitiesDeaf patientSevere respiratory disease Surgery of front teeth

Contraindications (Cons):

In UK and some other countries in March 1990, a far reaching document:The Poswillo Report3:In March 1990, chaired by Professor DE Poswillo published the report of a working party on general anaesthesia, sedation and resuscitation in dentistry

Getting to know available guidelines

3.Poswillo D. General Anaesthesia, sedation and resuscitation in dentistry: Report of an expert working party. London: Department of Health, 1990.

“A carefully controlled technique in which a single intravenous drug or a combination of oxygen and nitrous oxide is used to reinforce hypnotic sedation and reassurance in a way which allows dental treatment to be performed with minimal physiological and psychological stress, but which allows verbal contact with the patient to be maintained at all times. The technique must carry a margin of safety wide enough to render unintended loss of consciousness unlikely. In addition, any technique of sedation other than as defined above, be regarded as coming within the meaning of dental general anaesthesia”

Recommendations

Anaesthetic training should include specific experience in dental anaesthesia

Dental undergraduates should be taught principles of Physiology and clinical practice of anaesthesia

Dental anaesthesia itself should be regarded as a postgraduate subject

Wherever possible, the use of general anaesthetics should be avoided , if required all dental anaesthesia be given by accredited anaesthetistsFacilities: multipara monitors, DC defibs, capnograph, adequate suction and operating light & other equipments“Single handed” operator/anaesthetist” -discontinued Supine position for patient undergoing general anaesthesia

Recommendations (Cont)

Intensive courses on intravenous sedation

Appropriate refresher courses

‘British Standard’ relative analgesia machines

Skill and competence must be obtained by dentists in resuscitation & BLS skills

Recommendations (Cont)

Because of elaborateness of the report --lot of hue and cry

Warning that: Demise of ‘GA in Dentistry is for sure’, were proven wrong!

Revised and amended by General Dental Council

Approved by Leo Strunnin, President, Royal College of Anaesthetists8

8. Woodman R. Dental council aims to cut anaesthetic rate. BMJ 1998; 317: 1407.

Personnel relatedOnly Anaesthetists on GMC Specialist register or Trainee Anaesthetists in approved training programs orNon consultant career grade Anaesthetists working under the supervision of consultant Anaesthesiologist

The Atmosphere of Pessimism, due to these in-depth and very stringent guidelines

Specified equipment relatedAnaesthesia is to be administered using nasal inhalerCuffed nasal airwaysMonitoring very high standard

Surgical equipment related Mouth packs are essentialDental surgery should be practiced mainly as inpatient rather than outpatient

Problems associated with Resources Backup support system Professional liability of individual.Insurance coverage Special drugs e.g. :- Dantrolene sodium for malignant hyperthermia patients.

6. Silker ES. Office based anaesthesia (ASA OBA Guidelines- ASA Guidelines- ASA House of delegates): New Orleans: 1999.

While in USA, workshop “ASA, OBA guidelines-ASA House delegates” (New Orleans, October 1999)6 - the problems raised & discussed:

Getting to know available guidelines (contd.)

Problems associated with venue Availability of reliable unending medical gases both oxygen as well as nitrous oxide.Electrical generator backup.Sophisticated equipment: monitors, infusion pumps, wall suction, alternative electrical suctionAvailability of support personnel: trained nursing staff, O.R. personnel.Availability of additional anaesthetic personnel

Essential equipment:Anaesthesia machine is desirable but not essential, provided a self inflating resuscitation bag and equipment for securing airway is available.Equipment like D.C defibrillator is considered as essentialTraining Trained anesthesiologist is the central figure.ACLS certification is must.Ongoing and continuous updating is needed.

Miscellaneous Designing/ construction of such a facility to conduct these procedures requires serious planning.Financial implications. Guidelines by American Dental Society of Anaesthesiology (ADSA) are more liberal Unlike in UK, In USA, there is a 1 year Fellowship in General Anaesthesia equivalent to residency in anaesthesia and dental surgeons are permitted .

Actual Existing Circumstances in India and Our own experience

Growing interest in Dental Anaesthesia“ Literacy, awareness , access to internet and increased demand about “Pain & anxiety Free Dentistry”So..Newer Anaesthesiologist ask about:

Setting up the serviceUnderstanding the pros and cons about it Most important :- the medico legal implications

No guidelines prescribed in our country Western practice set up - two diagonally opposing sets of guidelines existing on the two sides of Atlantic (UK Vs. US)Under the given dilemmatic circumstances, one is fraught with ambiguity Our efforts to Amalgamate both the philosophies and tailoring it to suit the current practices in our country

Actual Existing Circumstances in India and Our own experience (Cont)

THE SET UPIn our dental college in the department of Paedodontics - Dental Outpatient Anaesthesia Room (DOAR). Typical Dental Chair with all the paraphernalia suiting requirements for all the dental outpatient procedures. Cases of OMF/ Paedodontics procedures are also performed here

Actual Existing Circumstances in India and Our own experience (Cont)

INFRA STRUCTUREEquipment

Anaesthesia machineAll other safety featuresNo central O2 or N2O pipe line, so we have kept gas cylindersA working set of resuscitation equipmentOxygen delivery devices

Actual Existing Circumstances in India and Our own experience (Cont)

Stand alone electrical working suctionAdditional equipments like, syringe pump, IV fluid giving stand etcRefrigeratorDrugs and ConsumablesIntravenous Anaesthetic agents, mainly Propofol & MidazolamMonitoring equipments

Other drugs of resuscitation and support. Anticholinergics like atropine & glycopyrrolate

IV Cannulas, Syringes, Three ways etc.

Recovery Room

Personnel

D O A R

MATERIALS USED

Effect of Propofol, Midazolam & their

Combination in day care patients undergoing Oral and

Maxillofacial Surgical Procedures

MODIFIED HAMILTON ANXIETY RATING SCALE (M-HAM-A)

1. Anxious mood 2. Tension 3. Fears 4. Insomnia 5. Difficulties in concentration and

memory 6. Depressed mood 7. General somatic symptoms:8. General somatic symptoms:

Sensory 9. Cardiovascular symptoms 10. Respiratory symptoms 11. Gastro-intestinal symptoms 12. Other autonomic symptoms 13. Behavior during interview

MODIFIED HAM-( A ) score for level of anxiety :

<17 : mild

18 – 24: mild to moderate

25 – 30: moderate to severe

METHODOLOGY

Inclusion criteria

Availability of informed consent.

Age between 18-50 years.

ASA Physical status Class I & II.

Hemodynamically stable patient

with all routine investigations within

normal limit.

Elective surgery

Duration of surgery between 30-150

minutes.

Exclusion criteria Patient unwilling or hesitant for the procedure

Known history of egg allergy

History of adverse reaction or allergy to any drug

used during anesthesia

Patients with systemic disease…

Pregnancy.

Known alcoholic.

Anticipated prolonged surgery

Patients with full stomach with chances of aspiration

Patients requiring emergency procedure

Patients with compromised airway

Recent administration of CNS depressant drugs

To compare and assess the clinical efficiency of sedation….

Prospective, randomized, double blind, controlled study

60 subjects of either sex, randomly allocated

Propofol

Midazolam &

Propofol- Midazolam Combination

Group A: Propofol bolus & continuously maintained by infusion of Propofol.

Group B: Midazolam bolus & continuously maintained by infusion of Midazolam.

Group C: Induction by Propofol & continuously maintained by infusion of Midazolam.

METHODOLOGY (Cont)

INJ. PROPOFOL Bolus: 1 mg/ Kg IV Maintenance dose: 0.5-0.6 mg/ Kg/ hrAverage: 25-30 mg/hr.

METHODOLOGY (Cont)

INJ. MIDAZOLAM Bolus: 0.03 mg- 0.3 mg/KgMaintenance: 0.03-0.2mg/Kg/hr. Permitted range: 1.5 mg- 10 mg/hr. Average: 5 mg diluted in 25-30 ml/hr.

METHODOLOGY (Cont)

INJ. PROPOFOL & INJ. MIDAZOLAMBolus: Inj. Propofol 1 mg/ Kg IV

Maintenance: Inj. Midazolam in a dose of 0.03-0.2 mg/Kg/hr.

Permitted range of Midazolam for maintenance: 1.5 mg-10 mg/ hr. Average: 5 mg diluted in 25-30 ml/hr.

METHODOLOGY (Cont)

Ten minutes after the infusion of sedative agents, the local anesthetic is allowed to be injected (comprising 2% lignocaine hydrochloride with 1:100,000 adrenaline).

METHODOLOGY (Cont)

Patient's verbal response is continuously monitored during the procedure

Warning signs : Patient is apprehensive/anxious/uncomfortable Persistent closing of mouth Spontaneous mouth breathing Responds sluggishly to command Patient becomes uncooperative Patient has uncoordinated movements Patient talks incoherently

METHODOLOGY (Cont)

The drug administration was stopped After surgery sent to the recovery room & monitored for 2 hours. IV access was maintained for at least for 2 hours and until discharge criteria are met Discharge instructions were reviewed

METHODOLOGY (Cont)

METHOD OF STATISTICAL ANALYSIS

Analysis of variance (ANOVA) to test the hypothesis of the significance difference among the groups.

Chi-square Test of association to determine the association between the categorical variables.

Student’s t – test to test the hypothesis of significant difference for inter-comparisons of groups

Result: There is no significant difference in Age among the groups. The age of patients is equally distributed among the groups.

Comparison of Age factor among the groups

31.40

27.95 27.30

8.78 8.38

5.67

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

Group A Group B Group C

Groups

Ab

solu

te V

alue

Mean Standard Deviation

Result: there is no significant difference in weight among the groups. The weight of patients is equally distributed among the groups.

Comparison of Weight among the groups

57.7054.00

50.95

11.067.04 7.69

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

Group A Group B Group C

Groups

Abso

lute

val

ue

Mean Standard Deviation

Result: As p value = 0.07 > 0.05 implies that, there is no significant difference in Hamilton anxiety score among the groups i.e. the anxiety level among all the three groups was same.

Comparison of Hamilton - Anxiety Score among the groups

21.5022.80 23.00

2.48 2.80

1.03

0.00

5.00

10.00

15.00

20.00

25.00

Group A Group B Group C

Groups

Abso

lute

val

ue

Mean Standard Deviation

Result: There is no significant association between ASA grading & groups. It implies ASA grading within each group is equally distributed.

Distribution ASA grading among the patients

16 (80%)

12 (60%)

11 (55%)

4 (20%)

8 (40%)

9 (45%)

0

2

4

6

8

10

12

14

16

18

Group A Group B Group C

ASA - Grading

Abso

lute

cou

nt

Grade - I Grade - II

Result: There is no significant difference in average duration of surgery among the groups.

Comparison of Duration of surgery among the groups

52.50

34.50

39.00

32.10

15.0418.04

0.00

10.00

20.00

30.00

40.00

50.00

60.00

Group A Group B Group C

Groups

Abso

lute

val

ue

Mean Standard Deviation

Result: The proportion of Deep, Eye closed, rousable on mild stimulation was more in Group C as compared to Group A & Group B.

Comparison of Sedation score among the groups

2

7

9

2

0

1

7

12

0

2

4

14

0

2

4

6

8

10

12

14

16

Fully Awake & oriented Drowsy Eye open Drowsy Eye Closed but rousable Deep ,Eye closed rousable on mild

stimulation

Sedation Scale

Ab

solu

te c

oun

t

Group A Group B Group C

Result :Operating condition score was good in Group A when compared between Group B & Group C.

Operating Condition among Groups

12

7

11

9

10

0

3

17

0

2

4

6

8

10

12

14

16

18

Good Fair Poor

OC Levels

Abso

lute

Cou

nt

Group A Group B Group C

Result: There is statistically highly significant association between degree of amnesia & groups. It implies that proportions of totally amnesic patients are statistically more in Group C than other groups.

Distribution of Amnesic patients among the groups

14

4

76

13

16

0

2

4

6

8

10

12

14

16

18

Group A Group b Group C

Groups

Abs

olut

e co

unt

Partially Amnesic Totally Amnesic

Result: There is statistically highly significant association between incidence of side effects & groups. It implies that proportion of incidence of side effects is less in Group A than other groups.

Distribution of Incidence of Side Effects

1

12

1819

8

4

0

2

4

6

8

10

12

14

16

18

20

Group A Group B Group C

Groups

Abs

olut

e Co

unt

Yes No

Result: There is statistically highly significant association between Discharge Score & groups. It implies that proportion of Discharge Score Average is more in Group A than other groups.

Comparison of Discharge Score among the groups

9.30

8.308.00

0.57 0.470.00

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

Group A Group B Group C

Groups

Abso

lute

Val

ue

Mean Standard Deviation

Pre-operative Procedure (T0)

At Induction (T1)

At LA Administration (T2)

At the beginning of Surgical Procedure (T3)

At the end of surgical procedure (T21)

At the recovery room at the time of discharge

Pulse Rate SPO2

Systolic Blood Pressure

Diastolic Blood Pressure

BASE OPERATIVE VITALS:

Comparison of Pulse Rate between the Groups at all Time Points

60

62

64

66

68

70

72

74

76

78.

80.

Time Point

Mea

n P

uls

e R

ate

Group A Group B Group c

Group A 77.85 70.25 74.00 72.55 72.15 72.40 71.74 70.92 70.30 71.20 72.20

Group B 78.45 69.50 74.20 72.25 70.80 69.95 69.54 69.11 68.55 69.15 70.30

Group C 78.80 69.70 73.90 70.30 68.70 67.89 67.54 68.00 68.10 69.80 71.90

T0 T1 T2 T3 T4 T5 T6 T7 T19 T20 T21

Pulse Rate is better in Group A when compared with other groups

Comparison of SPO2 among the Groups at all time points

92.50

95.00

97.50

100.00

Time Point

Mea

n S

PO

2

Group A Group B Group c

Group A 98.50 97.95 97.75 97.65 97.80 97.90 97.67 97.58 98.05 98.50 98.55

Group B 98.40 97.60 97.50 97.15 97.05 96.79 96.23 95.78 96.85 97.40 98.20

Group c 99.00 98.00 98.00 97.60 97.40 97.37 97.86 97.67 97.55 97.95 98.50

T0 T1 T2 T3 T4 T5 T6 T7 T19 T20 T21

SPO2 is better in Group A & Group C when compared with Group B

Comparison of Systolic BP among the groups at all points

100

105

110

115

120.

125.

130.

Time point

Mea

n S

ysto

lic B

P

Group A Group B Group c

Group A 124.50 120.50 125.30 124.10 124.20 124.10 123.11 122.77 121.80 123.40 123.90

Group B 123.50 119.10 123.90 122.55 120.70 119.33 119.69 119.00 118.70 119.85 121.00

Group c 120.70 116.30 119.20 117.40 116.10 115.05 115.57 115.56 115.70 117.10 118.90

T0 T1 T2 T3 T4 T5 T6 T7 T19 T20 T21

Systolic BP better in Group A when compared with other groups

Comparison of Diastolic BP among the Groups at all Time points

65

70

75.

80

85.

Time Point

Mea

n D

iast

olic

BP

Group A Group B Group c

Group A 84.00 80.50 84.80 84.15 83.90 83.60 82.33 81.33 81.40 82.40 83.30

Group B 83.30 79.70 84.00 82.50 80.90 80.11 79.69 78.80 78.80 79.60 81.00

Group c 80.40 77.20 79.20 76.80 75.80 74.95 75.00 75.11 75.50 76.65 78.80

T0 T1 T2 T3 T4 T5 T6 T7 T19 T20 T21

Diastolic BP better in Group A when compared with other groups

In the present study we conclude that ….

• Propofol Bolus dose: 1mg/kg and Maintenance dose: 0.5mg-0.6mg/Kg/hr

is better than

• Midazolam Bolus dose: 0.03mg-0.3 mg/kg & Maintenance dose:0.03-0.2mg/kg/hr

and • Combination with (induction by Propofol 1mg/Kg +

Maintenance by Midazolam)

SUMMARY & CONCLUSION

Sedation level is optimum

The operating condition were ideal.

Fluctuations in the hemodynamic profile, but there were no

incidence of deviation from expected pattern.

Recovery is very rapid and uneventful

Partial amnesia

Discharge criteria were successfully fulfilled and the scoring was high

Patient’s satisfaction were highest with the use of Propofol

Group A (PROPOFOL 1%) is better when compared with other Groups:

SUMMARY & CONCLUSION (Cont)

RECOMMENDATIONS

General Anaesthesia or its variants in association with dental outpatient practice have very specific indicationsThe conduct of Anaesthesia is not with specific problemThe ease of local analgesia is very appealing, but if the patient demand GA, or there are specific indications, then it justifies the troubles of giving GAAs a new developing, challenging field this can be very usefulThe setup is very important, so initial investment has to be considered.

Dental Chair Anaesthesia is steadily gaining popularitychallenging, new, unexplored but promising territoryBalancing of ‘Pros & Cons’ for: conscious sedation,relative analgesia or Actual GA dispute in prescribing the guidelinesSetting up the services is as such not easy, cheap, or frivolous and simpleMust be done by trained qualified anaesthesiologistsProper homework, preparation and execution are absolutely essential

IN CONCLUSION

“There is absolutely no justification in exposing the patient to any danger resulting in any morbidity & mortality especially when the patient has come to get treated for a very trivial, superficial and absolutely noninvasive surgery.” “However if it is deemed necessary to venture upon this , then Proper Homework, Preparation and execution : essential.

Unforgettable Principle!

Thank You !