Intravenous Sedation II Flashcards
Purposes of sedation?
Control fear, anxiety, apprehension
Reduce stress associated with unpleasant/painful procedures
Control severe gag reflex
Tx of uncooperative pts, including children and disabled pts
To stabilise BP of pts with hypertension and history of CV or cerebro-vascular disease
Advantages of intravenous sedation?
Given remote from operating site Administered as single dose Rapid onset Mouth breathing not important Pt cooperation less important Sedation attained pharmacologically Excellent amnesia No pollution
Disadvantages of intravenous sedation?
No clinically useful analgesia
Overdose can lead to profound respiratory depression
Laryngeal reflexes obtunded for a short period?
Occasional disinhibition effects
Occurrence of sexual fantasies
Pre/post op instructions must be followed
Pt management techniques?
Time and TLC LA Pyschotherapy Hypnosis Acupuncture Inhalation sedation Oral/transmucosal sedation IV sedation GA
How to minimise anxiety?
Empathy Kindness Explanation Support Time Gentleness
Be calm Smile Talk to pt, know their name Read notes Stay close Offer encouragement Explain what will happen End of positive note
How to take a medical history prior to sedation?
Written questionnaire completed with pt Verbal discussion with patient Contact GP Liaise with other health care professionals Advice from consultants
Dental history prior to sedation?
Attitude to dental care Past history Past experience of sedation and GA Recent history Main dental problem
What to consider prior to the dental procedure?
Tx required Length of procedure Degree of trauma involved Multiple visits Acute infection Degree of pt cooperation required Radiographs required during tx
What social history to consider prior to the procedure?
Able to provide a responsible escort Ability to understand and follow pre and post op instructions Someone to help at home Able to take time off work Someone to look after children Someone to stay overnight Transport to and from surgery
What is informed consent?
Informed consent explains the benefits of tx, risks and disadvantages of treatment and the tx alternatives to the patient in a language that they understand
What to do if a pt is unable to consent for themselves?
Discuss everything with next of kin
Discuss tx with care staff
Have 2 professionals (doctor/dentist) independently agree that this tx is in the best interests of the pt
Names person to sign pre/post op instructions
Liaise with parents/GP regarding MH
Appoint IMCA
What needs to be physically assessed prior to IV sedation?
Colour Pulse Respiration Arterial oxygen saturation BP Weight or BMI Degree of understanding and cooperation
What other investigations may you do prior to the sedation?
Liver function test ECG Sickle cell test FBC INR Clotting screen
Clinical effects of benzodiazepines?
Anxiolysis Sedation Hypnosis Amnesia Anticonvulsant Decrease in skeletal muscle tone
Contraindications to IV sedation?
Allergy to benzodiazepines Pregnancy Age ASA III, IV, V (requires a hospital setting) Poor veins High or very low BMI Respiratory depression Acute pulmonary insufficiency Sleep apnoea Severe hepatic impairment
What to be wary of with sedation?
MANY drug interactions
What can midazolam interact with?
ACE inhibitors (BP) - Enhanced hypotensive effect
Alcohol - enhanced sedative effect
Alpha blockers - enhanced hypotensive and sedative effects
Antidepressants - enhanced sedative effect
Antihistamines - enhanced sedative effect
Betablockers - enhanced hypotensive effect
What equipment is needed for sedation?
Midazolam, note expiry date/batch Saline for injection 2x5ml syringe Straight filter needle for drawing up drug Pre injection swap Tegaderm patch to secure cannula 22G cannula Gauze Yellow sharps box Tourniquet
Oxygen and emergency oxygen
Cylinder capable of giving 15litres/min
Suction
Emergency suction
Emergency drugs
- Flumazenil
What drugs are used to sedate?
Midazolam 5mg/5ml (1mg/ml)
Saline for intravenous administration
What is the reversal agent for midazolam?
Flumazenil/anexate 0.5mg/5ml (100mcg/ml)
Normal values of vital signs to compare to the pt?
Weight 70kg Temp 36-37.5 degrees Colour pink, well perfused Pulse 70bmp, full volume, regular Resp: 12-20 regular breaths per minute BP 120/180mmHg 16/10KPa Temperature: Hot and sweaty because unwell or anxious?
How to assess the pts level of consciousness?
Stand unaided with eyes closed Romberg test Touch nose with forefinger Loss of facial expression/animated Eyes open/closed/ptosis Speech slurred/slow Response to verbal command
Respiratory obstruction?
Potentially fatal complication
Can lead to coughing, straining, vomiting and regurgitation
Suspect if snoring, paradoxial chest and abdominal movement, straining
Airway causes (edentulous pts)
Tongue
Can also be caused by swelling, tumour, irradiation, epiglottis, restricted jaw opening
Minimal monitoring needed for IS AND IV sedation?
For IS - dental team observation
For IV - dental team observation supported by electronic blood pressure and pulse oximeter readings
- Baseline BP should be within normal range for age and physical status
- Pulse oximetry: measures arterial oxygen saturation, non-invasive, accurate
What principles is pulse oximetry based on?
Difference in absorption spectra of reduced and oxygenated haemoglobin
The beer lambert law
That only reduced and oxy-haemoglobin are present in the blood
Paperwork needed for sedation?
Written consent
MH
Signed pre and post op instructions
Contemporaneous sedation record sheet
Transmucosal sedation?
Sublingual
Rectal
Intranasal
Transmucosal administration?
Avoids venepuncture
Rapid absorption and onset
Drug directly enters systemic circulation, bypasses entero-hepatic circulation
Good pt cooperation
Avoids pollution
Blood levels significantly higher than after oral administration
Once administered effetcs cannot be terminated
Transmucosal midazolam?
Very bitter taste
ph 3.5 - stinging intra-nasally
Use concentrated formulation
Studies used 0.2-0.5mg/kg for premedication and sedation in children
Drugs for oral sedation?
Temazepam
Midazolam
Diazepam
Nitrazepam
Advantages of oral sedation?
Administered as single dose Given remote from operating site Mouth breathing not important Pt cooperation less important Pharmacology rather than psychology Good amnesia No pollution No venepuncture required
Disadvantages of oral sedation?
Slow onset, uncertain effect No clinically useful analgesia Once administered effects cannot be discontinued or switched off Dose is estimated rather than titrated Occasional dis-inhibition effects Pre and post op instructions need to be followed as for IV sedation Training Some drugs cause gastric irritation
