Sedation & Anesthesia in Dental Practice

ORAL / IV SEDATION for DENTISTRY: “How-to” Applications, Clinical Pharmacology and Controversies New Orleans Dental Conference Louisiana Dental Association Annual Session April 11th, 2015 Mel Hawkins DDS, BScD AN, FADSA, DADBA Dentist / Dentist Anesthesiologist Toronto, ON Canada

Current Issues

► Safety in Pediatric Dentistry ►

State Dental Boards now requiring permits for Oral Sedation

► Guidelines – ADA ’08 - shift  level intended Status / Safety of a single re-dose or multiple ► dosing / “titration” of oral sedatives Who’s responsible / recognized for teaching? ► Universities? ADSA? Fee for profit outside organizations e.g. D.O.C.S?

What today is NOT:

WHAT TODAY IS: 1

3

2

Regulations, Definitions, Pharmacology Age/Risk

Sedatives, Anxiolytics, Reversal, Children

Sedation Practice Management Consent, Rules, Fees

1 Regulations, Definitions, Pharmacology

Age/Risk

ORAL SEDATION DENTISTRY REGULATIONS: LOUISIANA STATE BOARD OF DENTISTRY. Complete a 8-hour classroom didactic course with a medical emergency component If anxiolysis (minimal sedation) is the objective, then no permit is required. ACLS is required, however. Pediatric 90% eliminated. This time will far exceed any possible clinical effect and has a legal implication.

GENERAL PHARMACOLOGICAL PRINCIPLES PHARMACODYNAMICS

Definition: Pharmacodynamics

“Dynamics” is what the drug does to the body.

Pharmacodynamics Actions and effects drugs produce on the CNS to practice sedation for dentistry • Desirable or “primary” - what you want it to do! AND/OR

• Undesirable or “secondary” – Side, adverse and lingering effects – Toxicity

An effect may be regarded as primary in one patient, but adverse in another (e.g. opioids)

Pharmacodynamic Definitions: POTENCY Milligram dose amount required to produce a certain effect (e.g. a “level 2” sedation). Same effect, arbitrarily, might be produced by: 0.25 mg. of triazolam, p.o. 15 mg. of diazepam, p.o. 2 mg. of lorazepam, p.o. 1 mg. of midazolam, iv. These could be termed “equipotent” doses

PHARMACODYNAMICS: AGE AND RISK

Pharmacodynamics: Age/Risk SENIOR CITIZEN “AVER-AGE” PATIENT PEDIATRIC CONSIDERATIONS

The Senior Citizen Although inaccurate, a “senior” in our society is usually defined as 65 years old.

A “bad day” will usually happen because of an attack of a pre-existing condition...

Geriatric Considerations Physiology Age of 65 is arbitrary. How often do we see a 65 year old who looks 50 and vice versa?

Hepatic metabolism and renal clearance can be reduced by 50% in patients over the age of 65.

Geriatric Considerations

Fear Factors: • Loss of function and independence • Long term institutionalization and isolation • Disability • Death

Geriatric Considerations

C.N.S:

• Loss of Neurons C.V.S:

• Systolic B.P.  with age • Rate  due to parasympathetic activity

Geriatric Considerations Pulmonary:

• Loss of alveolar septa •  elasticity of lungs • Impact of smoking

Geriatric Considerations

COMMUNICATION DIFFICULTIES

The “Aver-age” Patients ASA I or II are generally very safe sedation patients. ASA III is a judgment call. A “heart” patient is safer with sedation than without it. A “bad day” will usually happen because of lack of attention to the rules - doses, lack of good L.A. or “point of no return” feelings.

Why does Morbidity – Mortality “target” CHILDREN?

Children Although inaccurate, a “child” in our society is usually defined as up to 12 years old. A “bad day” will usually happen because of lack of respect of their airway...

Pediatric Considerations

C.V.S / C.N.S: The 2 MOST IMPORTANT Physiological Considerations in PEDIATRIC RESCUE are:

High MYOCARDIAL O2 Consumption High BRAIN O2 Consumption

Pediatric Considerations C.N.S:

The CPR / BLS guideline of: “3 – 6 minutes until permanent brain damage begins” is for the adult without an O2 debt and does NOT apply in pediatric life.”

Pediatric Considerations Drug (local anesthetic) impact: • Unpredictable • Blood Brain Barrier is immature •  Metabolism due to immature liver

Pediatric Considerations

COMMUNICATION DIFFICULTIES

2

Sedatives, Anxiolytics, Reversal, Children

SEDATIVES AND ANXIOLYTICS

Caveat #1 “The current trend in oral sedation is towards short ½ life agents and away from long ½ life drugs, even though the originally administered drug dose is below, by itself, the clinical effect. Adding another dose (or adding a 2nd drug) can more easily overdose because the system is primed. The risk is that there is a brain equilibration delay for a drug to get from the blood stream into the brain (several minutes).” ADSA Winter Review Course, Jackson D 2012

Sedatives/Anxiolytics

Conventional sedative-hypnotics (benzodiazepines) can produce a deep hypnotic state but cannot fulfill all requirements attributable to complete general anesthesia.

Sedatives/Anxiolytics BARBITURATES

BENZO DIAZEPINES

ANTI HISTAMINES

+++

++++

+++

+

++++

+++

Anticonvulsant

+++

+++

0

Anticholinergic

0

0

++

Antiemetic

0

0

++

Anterograde Amnesia

0

+++

0

Characteristics Sedation Safety

Sedatives/Anxiolytics

Benzo istamine A “Benzo-istamine” would be a good drug class, if it existed.

Triazolam, Halcion® Properties: • Sedative-anxiolytic, anti-panic, anticonvulsant, anti-spasmotic, muscle relaxant

• Subcortical & cortical actions • ½ life is 2-3 hours • No active metabolite (unlike diazepam  oxazepam which displays a 1/3 “rebound effect” at 6-8 hours)

• Administered orally or sublingually but are the same compound

Triazolam PRIMARY THERAPEUTIC EFFECTS (DESIRABLE):

• • • •

Anxiolysis Mild, pleasant sedation  euphoria Amnesia as dose increases, usually ~ level 2 Muscle relaxation also varies as to the benzodiazepine choice AMNESIA IS CONDITIONAL!

Triazolam SECONDARY THERAPEUTIC EFFECTS (UNDESIRABLE):

• • • •

Memory impairment same day, post op Over sedation/somnolence Psychomotor impairment – ataxia Talkative, aggressive, disinhibited or amorous behavior

Triazolam CONTRAINDICATIONS:

• Allergy • Myasthenia Gravis • Acute narrow angle glaucoma PRECAUTIONS:

• Young children and seniors

Triazolam ADVERSE RESPONSES:

• Respiratory depression if poly pharmacy ADULT DOSE DETERMINATES: 0.125 - 0.5 mg according to signs/symptoms of: apprehension,  drug history,  age and  weight, in that order

BUT  weight for the child 12 years old and younger

Triazolam METABOLISM

• CYP3A4 enzyme isoforms (hepatic and enteric)

• Only 45% of the drug enters the circulation due to 1st pass effect

• Sublingual triazolam has 28% more bioavailability than oral administration

• Direct absorption through sublingual capillaries means it avoids much of the 1st pass effect

Triazolam METABOLISM

• Clearance is variable. • Some chemicals inhibit CYP3A4, elevating blood levels of triazolam, e.g. Ritonavir®, antifungals, erythromycin and to a lesser extent, grapefruit juice

Benzodiazepine Comparisons TRIAZOLAM

DIAZEPAM

LORAZEPAM

Active Metabolite

No

Yes

No

Half-Life (hr.)

2-3

20-100

8-24

Onset (min.)

30-60 ?

60-90 ?

90-120 ?

Duration (hr.)

1-3

2-4

4-6

> 0.25 mg

> 20 mg

> 2-3 mg

Sedative Dose (p.o.)

Benzodiazepines: Diazepam (Valium®) Pharmacokinetic differences:

• Formulation of active metabolite (oxazepam) • Long elimination half-life (T½ Beta) but this does not correlate with duration of effect

• High lipid solubility correlates with rapid onset and short duration of clinical effect due to short distribution half-life (T½ Alpha). This applies to IV administration.

DOSAGES FOR CHILDREN

Oral Versed® - CHILDREN

• 15 ml Chocolate Syrup (i.e. Brown Cow) + sugar

• Versed injectable dosing: 0.5 mg/kg or 0.25 mg/lb • Up to a maximum of 15 mg. • With the M.C.M.S. Ohio: 20 mg.

Oral Versed® - CHILDREN ® Versed ,

If using more than 10 mg. then increase the amount of sugar. Mixture is more palatable when administered through a straw.

Flumazenil

® Romazicon

® Anexate

Flumazenil:

• Specific, high affinity competition for benzodiazepine receptors

• No intrinsic (agonist) activity of its’ own • Not highly lipid soluble, but low binding to plasma proteins allows rapid onset

• Short duration of action, 20-35 minutes

Flumazenil:

• Use only to reverse an inadvertently deeply sedated and poorly responsive patient (levels 3+)

• It is not to be used post-op as part of your sedation regimen

• Duration of reversal is shorter than the benzodiazepine that you are trying to reverse (resedation?)

Flumazenil Oral??? Dose and Route Comparison:

PO dose needs 6X volume of IV or IL dose

The “Catch 22” is: IF you feel that a case must be reversed orally, the amount of liquid needed to compensate for the first pass effect on flumazenil could create an emergency, i.e. aspiration (besides . . . . it’s messy!!)

Flumazenil: “How-to” How Supplied:

0.2 mg. per 2 ml. ampule 0.5 mg. per 5 ml. vial Result = 0.1 mg. / ml.

How To Use: In a 3 cc. syringe, draw 2 ml. (0.2 mg.) flumazenil (Romazicon®) How To Give: Inject 1 ml. (0.1 mg.) into ventral surface (under) the tongue or shallowly into floor of mouth

Flumazenil Results • Objective: To reverse poorly responsive sedation patient without reversing the anxiolysis!

• CAUTION: Do not over reverse an epileptic or chronic benzodiazepine user.

Flumazenil Results • GO SLOW, as with any drug. May not know their drug habits - convulsions can occur.

• Start with 0.1 mg, observe, continue with airway support, most cases some alertness starts to return in 5-7 minutes.

• If NO results after 10 minutes, inject another 0.1 mg.

The ZZZ DRUGS: zopiclone, Imovane® (C), Lunesta® (US) zaleplon, Sonata® zolpidem, Ambien®, Ambien CR® • They behave like benzodiazepine hypnotics • Potentiate GABA, an inhibitory neurotransmitter • Used to treat insomnia but can be used as sedatives in dentistry • Reversed by flumazenil (Romazicon®)

3 Sedation Practice Management Bad Days, Consent, Rules, Fees

DRUG SELECTION AND MODALITIES SEDATION BY PROCEDURE

Sedation by Procedure:

Restorative

Sedation by Procedure:

“The SALIVATOR”

Sedation by Procedure:

“The GAGGER”

EFFECTIVELY MANAGING YOUR ONSET, WORKING AND RECOVERY TIMES

TIPS ON BOOKING AND COORDINATING A PATIENT MANAGEMENT PRACTICE

1 Cancelation Warning

2 Flexibility N.P.O.

3 Patient Self Medication

4 1st appointment should be routine and non premed

5 Recovery In Chair

6

Control Your Onset Time

7 Operate Supine

8 Sit Up Quickly

9 Patient Accompanied Home

10 …Staffed Trained Equipped…

The Appointment

Pre-op Per-op Post-op

BEFORE THE APPOINTMENT

PATIENT CONSENT

PATIENT CONSENT

I,______________________, hereby consent to treatment with sedation for my pending dental appointment(s). I have read and fully understand and agree to adhere to all pre-op and postop instructions. I will not operate a motor vehicle for (18) 24 hours.

PATIENT CONSENT (con’t)

I have had the opportunity to ask questions and have had answered to my satisfaction my questions and concerns. I have been offered the opportunity of having another adult and/or translator with me.

PATIENT CONSENT (con’t)

I also grant permission to discuss my dental and sedation treatment with my accompanying adult, my spouse, partner, family member, friend or physician if deemed reasonably necessary for my immediate dental health and safety.

PATIENT CONSENT (con’t)

I understand the possible per and post-op sedation side effects. I have been informed of the reasonably expected recovery scenarios from being sedated and have asked and had answered to my satisfaction all my areas of concerns.

PATIENT CONSENT (con’t) I hereby give my consent to the application of sedation for dental treatment(s). Witness

Patient

Dated at

Signature

Mo/Day/Yr

Parent/Guardian

D.O.B

/ /

TO OUR PATIENTS: YOU CAN HELP YOURSELF,TOO!

3 SIMPLE STEPS FOR A PLEASANT AND SUCCESSFUL SEDATION APPOINTMENT

No solid foods 6 (8) hours prior to your appointment.

1

You will feel better. Some medical conditions or patients under physicians orders and taking certain medications are exceptions.

Please ask us!

Clear liquids permitted up to 2 hours before your appointment.

2

Suggestions include; coffee (decaf), tea with sugar, pop, Jello®, popsicles (non-cream) and water. No dairy, no juices with pulp. For washroom logistics, try not to over-consume fluids.

Your face and tongue may still be numb.

3

Avoid burns by consuming moderately warmed food and beverages. Parents, observe your children carefully for signs of lip, tongue or cheek biting.

THE APPOINTMENT

MONITORING

Pulse Oximetry What is it?

• A non-invasive, cost effective, reusable method of continuously measuring arterial percentage Hb saturation (and pulse rate)

• An indispensable safeguard against unexpected hypoxemia What isn’t it?

• This is NOT an early warning system!

Monitoring Options Options for monitoring adequate oxygenation

• Pulse oximetry measures percent hemoglobin saturation.

• PaO2 is then estimated according to oxyhemoglobin dissociation curve.

Oxygen Transport Only 1-2% Dissolved in Plasma (PaO2) 98-99% Bound to Hemoglobin SpO2 (Pulse Oximetry) SaO2 (Arterial Blood)

Pulse Oximetry Measures hemoglobin saturation (SpO2) Must extrapolate arterial oxygen tension (PaO2) SpO2 95 = PaO2 80 SpO2 90 = PaO2 60 SpO2 X = PaO2 (X-30)

Hypoxemia Defined as PaO2