CDS Sedation Flashcards

(232 cards)

1
Q

Special care dentistry

A

Dentistry for those with a disability or activity restriction that directly or indirectly affects their oral health

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2
Q

Problems in providing dental treatment in special care

A

Communication
Anxiety
Moving target
Perception of reality
Previous experience

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3
Q

Possible reasons for involuntary movements

A

Parkinson’s
Learning difficulties
Muscular dystrophy
Cerebral palsy
Multiple sclerosis
Huntingdon’s Chorea
Head injury

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4
Q

Why does Midazolam help with involuntary movements?

A

It is a muscle relaxant

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5
Q

Congenital vs acquired learning difficulties

A

Congenital - syndromic or non-syndromic
Acquired - trauma, infection, cerebral vascular accident, Alzheimer’s

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6
Q

Assessment of pts with involuntary movements

A

Mental and physical status
Anxiety
Pain experience

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7
Q

Assessment of pt with learning difficulties

A

Is behaviour management possible?
Is pharmalogical management needed?
PT understanding?
Pt pain experience?

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8
Q

What to do if a patient is competent to consent but can’t write?

A

Verbal consent, documented in notes

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9
Q

Adults with incapacity certificate

A

Medically qualified or appropriately trained dentists can complete a form allowing treatment for patients not competent to give consent, lasting for up to 36 months, as per the adults with incapacity act 2000 Scotland

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10
Q

Conscious sedation techniques

A

Inhalation
Intravenous
Oral
Transmucosal - rectal, intranasal, sublingual

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11
Q

Choice of sedation depends on

A

Patient cooperation
Degree of anxiety
Dentistry required
Skills of the dental team
Patient’s previous experience
Facilities available
Anaesthetist required?

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12
Q

Advantages of inhalation sedation

A

Useful for anxiety relief
Rapid recovery
Flexible duration

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13
Q

Disadvantages of inhalation sedation

A

Keeping nasal hood in place
Less muscle relaxation
Coordination of nasal breathing when mouth open - cooperation important, understand behavioural management

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14
Q

Advantages of IV sedation

A

Good sedation achieved
Less cooperation needed
Muscle relaxation

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15
Q

Disadvantages of IV sedation

A

Baseline readings
IV cannulation required
Assessing sedation level
Behaviour during recovery
Efficacy swallowing

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16
Q

IV sedation types

A

Midazolam
Propofol
Multiple agent

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17
Q

Safety considerations of IV sedation

A

Swallowing
Airway
Liver
Medical interactions
ASA - american society of anaesthesiologists assessment of health

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18
Q

Advantages of oral/transmucosal sedation

A

Avoids cannulation
Can make induction more pleasant
Better cooperation
Better future behaviour

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19
Q

Disadvantages of oral/transmucosal sedation

A

Baseline readings
Bitter taste/stinging
Lag time
Untitreable
Difficulty monitoring level of sedation
Behaviour in recovery

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20
Q

Possible outcomes from sedation

A

All required treatment could be carried out
Some treatment carried out - rest needs GA
Exam, scale and polish - refer to GA for treatment
Other treatments

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21
Q

Treatment planning for sedation patients

A

Pre sedation exam may not be possible
Ability to cope
Complicated treatment - maintenance in future
Treat the pt NOT the carer
Use sedation because of clinical need

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22
Q

Considerations for GA vs sedation

A

Safety - controlled airway with GA, difficult intubation
Cooperation
Waiting lists and access to services
Pain
Medical history
(Still a need for GA)

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23
Q

Dangerous sedation

A

Bolus sedation
Untrained seditionists
Incorrect doses due to wrong labels or incorrect concentration
Reliance on flumazenil

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24
Q

Types of sedation used in dentistry

A

Inhalation - nitrous oxide
Intravenous - usually midazolam (type of benzodiazepine) cannula in the hand

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25
Reverse midazolam
Flumazenil
26
Average dose of midazolam used in dentistry
5-6mg
27
What can be used before an appt to help anxious patients get there?
Pre med diazepam can be used 5mg tablet
28
Conscious sedation
A technique in which the use of a drug or drugs produce a state of depression of the central nervous system enabling treatment to be carried out, but during which verbal contact with the patient is maintained throughout the period of sedation
29
Complications of cannulation
Venospasm Extravascular injection Intraarterial injection Haematoma Fainting
30
Complications of drug administration
Hyper responders Hypo responders Paradoxical reactions Oversedation Allergic reactions
31
Venospasm
Disappearing vein, veins collapse at attempted venepuncture May be accompanied by burning sensation Associated with poorly visible veins Worse with repeated attempts, slow puncture or if pt is cold
32
Extravascular injection
Active drug placed into interstitial space Pain, swelling, delayed absorption Prevent with good cannulation and a test dose of saline To treat - remove cannula, apply pressure, reassure
33
Intra-arteiral injection
(when cannulating at elbow) Pain on venepuncture Red blood in cannula Difficult to prevent leaks Pain radiating distally from site of cannulation Loss of colour or warmth to limb/weakening pulse Prevent by avoiding anatomically prone sites such as ACF medial to biceps tendon Manage by monitoring for loss of pulse, discolouration or going cold. Leave cannula in situ for 5 mins post drug, if no problems remove and if symptomatic leave it in and refer to hospital
34
Haematoma
Due to damage to vein walls at venepuncture if poor technique or at removal of cannula if failure to apply pressure. Take care with elderly patients Treat with time, rest, reassurance If severe use ice pack initially followed by moist heat 20minutes in the hour following Consider heparin gel
35
Fainting during IV sedation
Anxiety related to venepuncture Worse if starved Prevention - topical skin anaesthesia, risk asses first, consider patient positioning Pt may lose bladder control, if bowel control is lost this is not a faint
36
Hyper responders to IV sedation
Deep sedation with minimal dose, 1-2mg midazolam, often elderly, titrate slowly in 1mg increments
37
Hypo responders to IV sedation
Little sedative effect with large dose Check cannulation May be due to tolerance - BZD users, cross tolerance Idiopathic Threshold to abandon is unknown
38
Paradoxical reactions to IV sedation
Unexpected reactions Appear to sedate normally, react extremely to all stimuli, relax when stimuli removed Check for failure of LA DO NOT ADD SEDATIVE Find other management technique Beware with teenagers
39
Oversedation with IV
Loss of responsiveness, respiratory depression, loss of ability to maintain airway, respiratory arrest STOP procedure Try to rouse pt, ABC, if no response to stimulation reverse with flumazenil 200micrograms then 100microgram increments at minute intervals Watch for 1-4 hours Manage respiratory depression by checking oximeter, stimulate pt, ask to breathe, supplemental oxygen nasal cannulae 2L per min
40
How to manage respiratory depression during IV sedation
Check oximeter Stimulate pt Ask to breathe Supplemental oxygen nasal cannulae 2L per minute Reverse with flumazenil
41
Half life of midazolam
Elimination half life of midazolam is 1-2 hours so can be in system for 12 hours
42
Oversedation during inhalation sedation
Turn it off, if pt comes round decrease by 5-10% before turning back on Do not remove nose piece
43
Management of patient panic during inhalation sedation
Reassure If pt can not cope abort
44
Signs of nitrous oxide overdose
Pt discomfort Lack of pt cooperation Mouth breathing Giggling Nausea Vomiting Loss of consciousness
45
Concentration of Nitrous oxide given in inhalation sedation
70% 30% oxygen
46
How can oversedation happen?
Initially by misjudging the dose Later - traumatic procedure over, mouth breathing ceases
47
GDC definition of sedation
A technique in which the use of a drug or drugs produces a state of depression of the CNS, enabling treatment to but carried out, but during which communication can be maintained and the modification of the patient's state of mind is such that the patient will respond to command throughout the period of sedation. Techniques used should carry a margin of safety wide enough to render unintended loss of consciousness unlikely
48
Guidelines for sedation
Standard for conscious sedation in the provision of Dental Care 2015 SDCEP Conscious sedation in dentistry 2017 Both very similar in content and set out the requirements for carrying out dental sedation safely, including the required training
49
GDP role in sedation
Be competent in the clinical assessment of patients who may then go one to have treatment under LA, GA or IV sedation Make patients aware of these options and discuss whether a referral is needed
50
What is sedation assessment for?
Full assessment that confirms the required treatment, whether sedation is needed and the preferred technique. Involves informed consent and provision of information to the patient to ensure that aftercare and treatment are as safe as possible
51
Essential considerations for assessment for sedation
Essential prerequisite Separate visit Physiology, pathology and psychology Good clear communication Pleasant surroundings and staff Promptness
52
Assessment appointment includes
History (social, dental, medical) Examination (general, oral, vital signs) Treatment plan Consent Information for patient and escort
53
Social history for sedation assessment
Try to determine nature of fear, phobia vs anxiety, general vs specific Anxiety questionnaire such as MDAS could be used Occupation Escort Alcohol Responsibilities such as children Transport Age
54
Dental history for sedation assessment
Referral source Previous bad experience Previous sedation/GA and any problems Symptoms - acute or chronic Proposed procedure
55
How long is the optimal working time under IV sedation?
45 minutes
56
Medical history for sedation assessment
Similar format to PMH for normal treatment - can use questionnaires as they provide prompts for the patient for things they may not see as relevant Always check drugs Drug history/drug allergies/previous anaesthetic/sedation
57
Why is a medical history so important for sedation assessment?
Drug interactions Almost all drugs increase the sedative effect of midazolam (alcohol, opioids, erythromycin, antidepressants, antihistamines, antipsychotics, recreational drugs)
58
What is ASA Classification?
American society of anaesthesiologist scale used to work out the risk of treatment by grading the patient
59
ASA I
Normal healthy patient Non smoker Minimal alcohol
60
ASA II
Mild systemic disease E.g. pregnant, well controlled asthma or epilepsy, slightly raised BP
61
Ideal blood pressure
Between 90/60 and 120/80 mmHg
62
ASA III
Severe systemic disease, limits activity but not incapacitating e.g. Insulin dependent diabetes mellitus, >6 months post MI or CVA, stable angina
63
ASA IV
Severe systemic disease, constant threat to life Severe COPD <3 months post MI, stenting, CVA
64
ASA V
Moribund, not expected to live >24 hours
65
ASA VI
Patient who is brain dead for organ donation
66
Where should ASA I sedation tx be done?
Primary care
67
Where can ASA II sedation treatment be done?
Primary care
68
Where should ASA III sedation treatment be done?
Secondary care
69
Where can ASA IV sedation treatment be done?
Must be done in secondary care
70
Why is respiratory disease relevant to sedation?
Almost all sedative agents will cause respiratory depression, so it important to know if a patient has sever asthma or other respiratory disease
71
Categories of psychiatric disease
Neurosis (anxiety, depression) Psychosis (e.g. schizophrenia)
72
There are many absolute contra-indicative drugs for sedation True or fasle
False Few absolute contraindications but many interactions
73
Pharmacodynamic drug reactions
Interaction between drugs which have similar or antagonistic effects or side effects eg. antidepressants cause respiratory depression, as do BZDs
74
Pharmacokinetic drug interaction
One drug will alter the absorption, distribution, metabolism or excretion of another, thereby increasing or reducing the amount of drug available to produce its pharmacological effects
75
Which type of drug interaction is most likely to affect sedation?
Pharmacodynamic
76
What should be done in the general examination of a patient at sedation assessment?
Examine for signs of anxiety Vital signs - HR - BP - oxygen saturation Weight and BMI
77
Which vital signs must be recorded at sedation assessment?
HR BP O2 saturation
78
Underweight BMI
<18.5
79
Healthy weight BMI
18.5-24.9
80
Obese BMI
30+
81
Properties of the ideal IV sedation agent
Anxiolysis Sedation Non irritant No adverse side effects Easy to administer Quick onset Quick recovery Low cost Amnesia
82
How do benzodiazepines work?
By acting on receptors in the central nervous system to enhance the effect of GABA, prolonging the time for receptor repolarisation and by mimicking the effects if glycine on receptors
83
What is GABA?
Gamma amino butyric acid, inhibitory neurotransmitter found in the cerebral cortex, motor circuits and CNS
84
What is glycine?
Inhibitory neurotransmitter (similar to GABA) found in the brainstem and spinal cord
85
What part of the benzodiamine structure allows them to attach to receptors in the CNS?
Benzene ring
86
What drug is usually used for IV sedation and what class is this?
Midazolam Benzodiamine
87
Why was sedation introduced in dentistry?
As an alternative to GA - GA in dentistry has lead to deaths GA in the dental chair is now illegal in Scotland, meaning less patients can be treated under GA
88
Conscious sedation GDC definition
A technique in which the use of a drug or drugs produces a state of depression of the CNS enabling treatment to be carried out, but during which verbal contact with the patient is maintained throughout the period of sedation. The drugs and techniques used to provide conscious sedation for dental treatment should carry a margin of safety wide enough to render unintended loss of consciousness unlikely
89
What level of sedation must be maintained in dentistry?
Must be such that the patient remains conscious, retains protective reflexes and is able to understand and respond to verbal commands "deep sedation" in which these criteria are not fulfilled must be regarded as general anaesthesia (in the case of patients who are unable to respond to verbal contact when fully conscious the normal method of communication with them must be maintained)
90
Indications for treatment with IV sedation in adult patients
Conditions aggravated by stress (hypertension, asthma, epilepsy etc) Conditions which affect cooperation - Parkinson's, spasticity disorders, SOME learning difficulties (in some IVS will make it worse as inhibitions will be lowered) Psychosocial reasons - phobia, gagging, fainting, idiosyncrasy to LA
91
Phobia
An irrational and uncontrollable fear, which is related to a specific object or situation. It is persistent, despite avoidance of the provoking stimulus. It has a direct effect on the patient's lifestyle
92
What is meant by transference of dental phobia?
Someone else has shared negative experiences at the dentist - usually either parents or friends of children - leading to the child becoming afraid of the dentist
93
Reasons people can find the dentist scary
Fear of criticism Fear of the dentist's dress Lack of communication Helplessness Invasion of the body orifice
94
Influences on dental phobia
Environment Surgery appearance Staff continuity Age Stage of development Socio-economic background
95
Dental indications for sedation
Difficult or unpleasant procedures e.g. surgical extraction of wisdom teeth, orthodontic extractions, implants
96
Advantages for the dentist of sedation
Decrease dentist stress Decrease staff stress Decrease patient stress Fewer medical incidents More productive appointments
97
Disadvantages of sedation
Training required - cost and time Equipment required Recovery time and after care
98
ASA class 1
Normal healthy patient
99
ASA 2
A patient with mild systemic disease
100
ASA 3
A patient with sever (or poorly controlled) systemic disease
101
ASA 4
A patient with severe systemic disease that is a constant threat to life
102
Which ASA groups can an IV sedation trained dentist treat?
ASA 1 or 2 (anaesthetist required for any other group)
103
Social contraindications for sedation
Unwilling patients Uncooperative Unaccompanied (IV) Children under 12 (IV) Very old patients
104
Dental contraindications for sedation
Procedure too difficult for LA Procedure too long Spreading infection - airway threatening, limits LA Procedure too traumatic
105
Medical contraindications to sedation
Severe or uncontrolled systemic disease Severe mental or physical disabilities - unable to communicate or unable to understand Severe psychiatric problems Narcolepsy - must maintain communication Hypothyroidism Intracranial pathology - loss of alertness could be result of sedation or pathology
106
Inhalational contraindications for sedation
Blocked nasal airway COPD Pregnancy
107
Indications for inhalation sedation
Anxiety - mild to moderate Needle phobia Gagging Traumatic procedures - extractions, oral surgery Medical conditions aggravated by stress Unaccompanied adults requiring sedation
108
Contraindications for inhalation sedation
Common cold - nose breathing required Tonsillar/adenoidal enlargement Severe COPD First trimester of pregnancy - unknown how much of a risk this is Fear of mask/claustrophobia Patients with limited ability to understand - including small children, minimum age 5-7
109
On completion of inhalation sedation
Adult patients may leave unaccompanied at dentist's discretion Child patients (<16 years) must be accompanied by a competent adult Prior to discharge, ask how patient felt procedure went and listen Patients may feel shivery - reassure pt that this is common and passes quickly
110
What is the success rate for inhalation sedation
Published data says 50-90%
111
What determines the likelihood of success of inhalation sedation?
Appropriate patient assessment and selection Differences in different pt populations Greater success for orthodontic extractions Poorer in pts with pain
112
Inhalation sedation recovery once treatment carried out
Increase O2 10-20% per minute until 100% Administer 100% O2 for 2-3mins before turning off machine Remove hood and turn off gas flow Return patient to upright slowly, give praise and reassurance
113
Why deliver 100% oxygen when finished treating patient under inhalation sedation?
To avoid diffusion hypoxia (a factor which influences the partial pressure of oxygen within the alveolus) This is a theoretical risk, the equipment always delivers enough O2
114
Where is inhalation sedation normally used?
PDS or dental hospital setting (rarely used in practice)
115
Labels top to bottom
Oxygen flow meter - measures flow rates of up to 10 L/min (reading taken from equator of ball, +/- 5% accuracy) Mixture control dial Flow control knob
116
What is the lowest concentration of oxygen given during inhalation sedation?
50% (there is only 21% O2 in air)
117
What is the oxygen flush button for in inhalation sedation?
Emergency use OR to fill reservoir bag
118
What is the reservoir bag in inhalation sedation?
Bag 2 or 3 litre (smaller available for children) to emulate patients lungs The bag should move visibly with every inspiration and expiration and must not collapse Helps to monitor respiration Want a level where the bag moves gently in and out
119
What does it mean if the reservoir bag flattens?
Not enough gas given
120
What does it mean if reservoir bag looks stuffed full?
Too much gas given
121
Ideal respiration rate
12-16 breaths per min
122
Why is it important that waste gas is scavenged during IS?
So that people in the room are not breathing in nitrous oxide
123
How is rebreathing of expired gases prevented?
Non return valve in the expiratory limb
124
Why is size of nasal hood important?
To create a seal so that nitrous oxide is not leaking out
125
Safety features of inhalation sedation set up
Air entrainment valve Oxygen flush button Oxygen monitor Reservoir bag Colour coding Scavenging system Oxygen and nitrous oxide pressure dials Pressure reducing valves One way expiratory valve Quick fit connection for positive pressure oxygen delivery Full tank (esp oxygen) kept on the back of machine, replaced if used between pts
126
Advantages of IS
Rapid onset (2-3 mins) Rapid peak action (3-5mins) Depth altered either way Flexible duration Rapid recovery No injection (for the sedation, LA still required) Few side effects to pt Drug not metabolised Some analgesia (though better for ischaemic than inflammatory pain) No amnesia
127
Disadvantages of IS
Equipment and gases expensive Space occupying equipment Not potent - must be a cooperative pt who just needs a little help Requires ability to breathe through nose Chronic exposure risk (unlikely) Staff addiction Difficult to accurately determine the actual dose (+/- 5% from reading, nasal hood leakage, if pt speaks they will breathe through mouth, crying can affect)
128
Signs of adequate sedation with IS
* Patient relaxed/comfortable * Patient awake * Reduced blink rate * Laryngeal reflexes unaffected * Vital signs unaffected * Gag reflex reduced * Mouth open on request * Decreased reaction to painful stimuli * Decrease in spontaneous movements Verbal contact maintained
129
symptoms of adequate sedation with IS
* Mental and physical relaxation * Lessened awareness of pain * Paraesthesia - lips, fingers, toes, legs, tongue * Lethargy/"a few pints", "why your mum is less grumpy after a glass of wine" * Euphoria * Detachment 'floating feeling' * Warmth * Altered awareness of passage of time * Dreaming * Small controllable "fit of the giggles"
130
Signs and symptoms of over sedation with IS
* Mouth closing - repeatedly * Spontaneous mouth breathing * Nausea/vomiting * Irrational and sluggish responses * Decrease cooperation * Incoherent speech * Uncontrolled laughter, tears * Patient no longer enjoying the effects * Loss of consciousness
131
Pre-op instructions for IS
* Have a light meal before appointment * Routine medicines as usual * Children accompanied by a competent adult * Adults accompanied to first sedation appt, afterwards they may attend alone * Do not drink alcohol on the day of appointment * Wear sensible clothing * Arrange care of children during and after your appointment * Plan to remain in clinic for up to 30 minutes after treatment
132
IS technique before introducing nitrous oxide
* Set up the machine * Select nasal hood (record size in notes) * Connect to hoses * Set mixture dial to 100% O2 * Settle patient in dental chair * Reinforce explanations of procedure * Set flow to 5-6L per minute * Position hood on patient's nose * Encourage nasal breathing * Check reservoir bag movements - Small movements = check seal and look for mouth breathing +/- decrease the flow - Movements too great = increase the flow rate * Patient to be comfortable with hood before proceeding - just let them breathe oxygen for about 1 min
133
Technique when introducing nitrous oxide during IS appt
* Ask patient to signal when begin to feel different * Reduce O2 by 10% * Wait 1 minute and repeat * After O2 reaches 80% reduce by 5% per minute * Stop titration when patient is ready for treatment Continue with semi hypnotic suggestion - feeling dreamy, floaty, relaxed
134
Monitoring of patient during dental treatment under IS
If patient over-sedated increase O2 in 5-10% increments until satisfactory sedation. If under-sedated decrease O2 in 5% increments until satisfactory sedation.
135
Properties of an ideal IV sedation agent
* Anxiolysis (actual goal) * Sedation (is actually a side-effect) * Non irritant * No side effects * Easy to administer * Quick onset * Quick recovery * Low cost * Amnesia - actually a useful side effect
136
How do benzodiazepines work?
Act on receptors in the CNS to enhance the effect of GABA gamma amino butyric acid, prolonging the time for receptor repolarisation and mimics the effect of the inhibitory neurotransmitter glycine on receptors
137
What are GABA and glycine?
Gamma amino butyric acid is an inhibitory neurotransmitter in the CNS, cerebral cortex and motor circuits Glycine is a similar inhibitory neurotransmitter, which acts in the brainstem and spinal cord
138
How are active benzodiazepines able to bind to receptors?
They all have a benzene ring
139
Respiratory effects of sedative agents
CNS depression and muscle relaxation Decreases cerebral response to increase CO2 (primary driver for breathing) (Synergistic relationship with other CNS depressants and increased respiratory depression in already compromised patients)
140
Cardiovascular effects of sedative agents
Decreased BP by muscle relaxation decreasing vascular resistance Increased heart rate due to baroreceptor reflex compensating for BP fall
141
Drug interactions of benzodiazepines
Any other CNS depressant Erythromycin Antihistamines Among others
142
Consideration for those who take diazepam or valium recreationally
These are also benzodiazepines, can develop a tolerance Because of this, less than 2 weeks allowed for diazepam prescriptions
143
Factors making sexual fantasies more common during IV sedation
Higher dose Operator of opposite sex to pt (dependent on sexuality) One of the reasons that seditionist can never be alone with pt
144
Diazepam as IV sedation drug
The first widely used BZD Insoluble in water so a preparation with propylene glycol must be used, which caused a lot of pain on injection Long elimination half life Risk of rebound sedation 0.1-0.2mg/kg Long recovery Unpredictable Far from ideal - now superseded by midazolam
145
Advantages of midazolam as IV sedation drug
Painless on injection as it is water soluble at pH <4 and lipid soluble at physiologic pH - allows passing of BBB blood brain barrier Rapid onset and 2-3x more potent than diazepam Short elimination half-life - shorter working time but safer Metabolised in liver and small amount extra hepatic in bowel so slightly less affected by liver disease than some
146
Midazolam elimination half life
90-150 minutes
146
147
pH of midazolam
3.5
148
Midazolam preparation
5mg/ml
149
Why has midazolam superseded Diazepam?
Painless injection Quicker onset Quicker recovery More reliable
150
Who must be present in the room during IV sedation?
Sedation trained operator (or two separate people) Sedation trained nurse
151
Who must be present in the recovery room?
Sedation trained nurse and patient's chaperone
152
What type of cannula used for IV sedation and why must it stay in the arm?
In-dwelling cannula It might be needed for a medical emergency More secure than alternatives and made of Teflon which rarely clots/blocks Comes in a range of sizes
153
Why is a butterfly cannula not recommended for IV sedation, and what could it be used for?
Metal part in the patients hand clots and obstructs very easily and it is easily dislodged Best use - when taking blood as it will only be in for a short time
154
Most common cannulation site for IV
Dorsum of the hand Accessible Superficial and visible BUT Poorly tethered vessels tend to move Affected by peripheral vasoconstriction so may need to warm hand
155
Second choice site for cannulation for IV sedation
Antecubital fossa (less stable and less easily accessed than dorsum of hand)
156
Important structures to avoid in cannulation at antecubital fossa and how?
Brachial artery and median nerve Keep lateral
157
Why are two visits minimum for IV sedation?
Must have an assessment visit
158
Safety procedure for IV sedation appointment
Pre op pulse and BP taken on the day to check nothing has changed Escort must stay in the building Check travel arrangements Check care responsibilities have been covered Consent - mandatory at assessment but reconfirm Ensure high volume aspiration on hand Monitor - pulse oximeter, non invasive BP every 5-10 Have on hand flumazenil and means of ventilation
159
How much time with useful sedation are you likely to get from IV sedation?
30-45min
160
How long do you keep a patient after IV sedation?
60 mins after last increment
161
Flumazenil
Preparation 500mcg in 5ml Dose 200mcg then 100mcg increments every 60s until response Reverses midazolam BUT shorter half life 50 mins so risk of re sedation
162
Delivery of IV sedation
Pulse oximeter and BP cuff on - take your pre op measurements and be aware of these during sedation Cannulate the patient and make sure cannula is properly positioned and stable, use elastoplast/dressing to keep in place. Then can start drug administration - midazolam 2mg initial bolus Watch for a full minute 1mg increments at 60 second intervals until suitable level of sedation achieved Recommended not to give more than 7.5mg, often 5mg is the most that you give
163
End point for IV sedation
* Slowing and slurring of speech * Relaxed * Delayed response to commands * Willingness to accept treatment * Verrill's sign -ptosis - drooping eyelids * Eve's sign - loss of motor coordination - to measure, get pt to shut eyes and reach hands quite wide to each side, then touch their nose with their finger, will often miss nose at end point
164
Average midazolam dose
5mg
165
Max Midazolam dose
7.5mg
166
Factors affecting midazolam therapeutic dose
Sleep Alcohol Stress Drugs
167
Recovery following IV sedation
* Escort can be with pt as the second person at this stage * Keep until 60 minutes after last increment (write down times of increments given) * Cannula - needs to be removed before leaving * Ensure patient can walk unaided Escort given post op instructions
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Respiratory depression management during IV sedation
Pulse oximeter will probably show this Talk, shake, hurt Head tilt chin lift jaw thrust Encourage deep breaths If this does not improve oxygen saturation - O2 2l/min via nasal cannulae first (tx can continue) - no improvement 02 5l/min via Hudson mask If not working - flumazenil
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Guidance used for conscious sedation
SDCEP 2017
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Key points of GDC definition for conscious sedation
Remains conscious Retains protective reflexes Understands and responds to verbal commands
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Paediatric sedation assessment history key points
Pain - pts in severe pain are already in heightened state of anxiety Nature of anxiety - dentistry as a whole or something specific Dental history - more likely to be anxious if a child is aware of a problem Medical history - may have been through anxiety provoking medical procedures
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Paediatric sedation assessment patient factors
Child must be on board with the idea or they will not be suitable for IS and hypnotic suggestion Monitors (like to know details) vs Blunters (do not) MCDASf 9 no dental anxiety >31 or any 5/5 extreme dental phobia
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Methods of pain and anxiety management in children
Non pharmocological behaviour management - hypnosis, CBT, tell-show-do LA Sedation GA
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What is NPBM?
Non pharmacological behavioural management such as hypnosis, CBT, tell-show-do
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Children being treated with LA
With good behavioural management, most children can manage treatment under LA alone A useful adjunct is sometimes computer controlled single tooth anaesthesia like the wand
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What is the wand?
Computer controlled single tooth anaesthesia system which delivers LA solution at a slow rate and a low pressure Because of the design of the system (without a traditional syringe) it can be useful with children who have become afraid of LA injections
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Methods of paediatric sedation
Inhalation Intravenous Alternative techniques - oral, transmucosal
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Inhalation sedation
Combination of pharmacology and behaviour management. IS with O2 and N2O is most widely used paediatric dentistry sedation Excellent safety record Easily titrated to the individual child's need Still necessary to use LA and in combination with behaviour management/hypnotic suggestion
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Nitrous oxide for sedation
Has a sweet odour, is pleasant to inhale and is non irritant Stored as a liquid in cylinders at about 43.5 bar Low tissue solubility giving rapid onset and recovery
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Indications for IS in children
Age - child must be amenable to hypnotic suggestion and understand nasal breathing Anxiety level - mild to moderate, can be helpful for needle phobic Management of gag reflex Medical considerations - conditions worsened by stress Previous positive IS experience Dental needs - more difficult extractions or tricky procedures
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Contraindications for IS in children
Too young to understand the concept - absolute minimum 4/5 Extreme anxiety (unless it is an older child determined to make it work) Medical considerations - intellectual impairment meaning that they can't understand hypnotic suggestion or nose breathing, nasal blockage, claustrophobia/mask phobia, myasthenia gravis Previous unsuccessful IS Fear of nasal hood Procedure at front of mouth - nasal hood can get in the way
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Why is it important to treatment plan IS carefully?
IS is much more likely to be successful if it has been discussed from the beginning of treatment, it is much less likely to be successful if it is brought up as a suggestion when the patient is already struggling with the treatment they are undergoing
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Consent considerations for IS in children
Check that pt and parent understand - What will happen - How the child will feel - Sensations such as tingling, floating - Reassure that they will be back to normal in 5-10 minutes - Ensure that they know that they will still need LA - Written pre and post op instructions
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Pre op instructions for Paediatric IS
Child can eat and drink but should avoid having a heavy meal Accompanying parent can NOT be in the surgery during IS if pregnant If the child has a blocked nose, get in touch as they cant have sedation as it won't work - colds in winter, hayfever in summer
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Post op instructions for paediatric IS
Child needs to be supervised by an adult for the rest of the day Can still go to school, make teacher aware that they have had sedation No contact sport or bike riding for the rest of the day
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Maximum level of IS signs
When child reports tingling or starts giggling/becomes over excited
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Why is it important to avoid moving nitrous oxide dose up and down during sedation?
This can make the child feel nauseous
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Most common IV sedation drug used for children
Propofol (more predictable than midazolam)
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Indications for IV sedation in children
Age - usually 12+ Anxiety moderate to severe, general dental phobia or fear of intra-oral injections (not sever needle phobic) Medical considerations - conditions worsened by anxiety, generalised anxiety, previous positive IV sedation PDH - previous difficulty, lots of treatment history or non Dental needs - complex or lots of treatment required
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Contraindications for IV sedation in children
Age <12 Needle phobic, uncomfortable with cannulation Medical considerations - intellectual impairment, wouldn't understand what's going on If patient really likes to monitor, unsuitable because of amnesic effect, unsuitable for those who can not handle lack of control Procedure too long
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Why is general anaesthetic usually required?
High volume of treatment need or very young pt
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What is TCI propofol?
Target controlled infusion TCI sedation Administered by anaesthetist in a low dose for sedation, continuously titrated for the degree of sedation Useful for very short and very long procedures Rapid onset and recovery
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Consent for IV sedation for children
Check understanding of patient and parent Written pre and post op instructions Child must be accompanied and cared for the rest of the day, taken home in a car or taxi Nothing strenuous or potentially dangerous for 24h No alcohol or sedative drugs Take care over texts and social media
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Assessment visit for TCI propofol
Weight, BP, HR Given topical anaesthetic cream EMLA to use on hand before coming in to sedation visit
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Paediatric IV sedation appointment structure
BP and HR checked Sedation delivered LA given Tx carried out Recovery checked - can they walk unaided Pot op instructions given in writing
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Alternative sedation (not IS or IV)
Oral and transmucosal Often midazolam Less controlled Suitable for minority Sometimes given so that cannulation can be done This is an advanced technique in children
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What is meant by poor oral health related QoL?
People missing school or work, not socialising with friends, could be struggling to eat, or could avoid smiling due to embarrassment, which can all be results of dental fear and anxiety
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What is the cycle of dental fear and anxiety and sedation?
Patient who experiences DFA will avoid until they have pain, then attend for treatment and have sedation to get through it, then disappear and avoid the dentist until the next time they have pain, which will result in them having sedation again
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Is psychological or pharmacological management of DFA more effective?
Research shows psychological interventions are more effective
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How is CBT used in DFA?
Can prepare pt to have sedation OR can stand alone as a method of controlling dental anxiety
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What is the guidance for conscious sedation?
SDCEP
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What is the objective of CBT?
Provide psychoeducation and use behavioural modification techniques and cognitive restructuring skills to challenge unhelpful beliefs and behaviours
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Dental anxiety
General type of fear Occurs without a present triggering stimulus Emotional response to an unknown danger or perceived threat Anticipatory due to previous negative experiences
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Dental fear
An intense biological response to immediate danger which is specific Encourages caution and safety
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Dental phobia
Most common specific phobia (11% UK adults) Clinical mental disorder Overwhelming and debilitating fear of an object, place, situation or animal Interference with daily life
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Aetiology of dental fear/anxiety/phobia
Direct experiences - having had painful tx Observations - have seen a parent or someone upset in a dental setting What you are told - friends/family/teachers/media depicting the dentist as something to be afraid of Personality - some traits are more commonly associated with phobias Genes - not born with it but might make you more vulnerable
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Potential triggers to DFA
1. Fear of a specific stimuli 2. Fear of a medical catastrophe 3. Generalised dental anxiety 4. Mistrustful of dental personnel
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What is trauma?
An event of actual or extreme threat of physical or psychological harm which an individual experiences as traumatic, and which causes long lasting effects - single incident trauma - complex trauma
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Why is treating phobic patients more difficult for dentists?
Can be stressful Can need up to 20% more time in the chair More extensive treatment may be required due to neglect Can have a number of FTAs
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Modified dental anxiety scale
A structured, validated, self-report anxiety questionnaire Validated for use age 16+ Score 5-25 >19 or 5/5 on a question = severe anxiety/phobia
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Structured Assessment of child patients with dental fear and anxiety
Modified child dental anxiety scale - faces version MCDASf A structured, validated, self report anxiety questionnaire Validated for use age 8-15 Score 9-45 >27 = severe DFA/phobia
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Why is it important to determine why a patient is anxious before treatment planning?
The problem may be fear of feeling out of control, or needle phobia, which could make sedation unsuitable
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Psychological approaches for DFA
CBT Hypnosis
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5 factors influencing fear and anxiety in building blocks of fear and anxiety 5 factors model
Situation Thoughts Moods Body sensations Behaviours
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Emotional component of DFA
Anxious Scared Shame Guilt Anger
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Physiological component of DFA
Increased HR Dry mouth Increased perspiration Butterflies in stomach Flushed face Increased muscle tension
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Cognitive component of DFA
Expectation of failure Catastrophising Fortune telling Magnifying (how bad it will be) Minimising (our ability to cope)
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Behaviour component of DFA
Avoidance Disruptive behaviour Increased muscle tension Safety behaviours - strategies used to help cope
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What is STOPP for managing DFA?
Stop Take a breath Observe your surroundings Put it into perspective Practice coping mechanisms
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Two of the main tools to use to alleviate physical reactions to DFA
Controlled breathing Progressive muscle reaction
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3 steps to break the cycle of DFA thoughts
Step 1 - catch the thoughts Step 2 - challenge the thoughts Step 3 - find alternative thoughts
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Quiet breathing
Contraction of respiratory muscles, mostly the diaphragm Increases thoracic breathing In turn thoracic pressure reduced Air pushed in along the pressure gradient - inspiration Expiration is passive
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What is used in more forceful breathing that is not used in quiet breathing?
Intercostal and accessory muscles
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What is the difference between quiet breathing and forceful breathing?
In forceful breathing intercostal and accessory muscles are used
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What drives airflow in breathing?
Pressure gradients When atmospheric pressure>alveolar pressure - inspiration When alveolar>atmospheric - expiration
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Effect of posture on breathing
Contraction of diaphragm drives respiration Movement of diaphragm can be complicated by abdominal cavity contents, its movement is facilitated in sitting position as compared with lying down
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Obstructive pulmonary diseases
Asthma Emphysema Bronchitis
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Conduction zone of airway
No gas exchange, anatomical dead space Trachea, bronchi and bronchioles
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Respiratory zone
Region of gas exchange Respiratory bronchioles, alveolar ducts and alveolar sacs
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How do gases move over alveolar wall?
Diffusion
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