SEDATION Flashcards
What is conscious sedation?
This is sedation where the patient is still concious, retains protective reflexes and is able to understand and respond to verbal commands during treatment.
List some medical indications for sedation.
- Medical conditions that are worsened by stress:
- Ischaemic heart disease
- Hypertension
- Asthma
- Epilepsy
- Psychosomatic illness
- Medical conditions that affect co-operation
- Mild/moderate movement or learning difficulties
- Spasticity disorders
- Parkinsons
- Psychosocial
- Phobias (Dentist/drills/needles/Gagging)
List some dental indications for sedation.
Difficult or unpleasant procedures
Surgical extraction of wisdom teeth
Orthodontic extractions
Implants.
List some contraindications for sedation
- Severe or uncontrolled systemic disease
- Severe mental or physical disability (unable to communicate or understand)
- Severe psychiatric problems
- Respiratory depression.
- Narcolepsy- condition where you suddenly fall asleep (loss of communication under sedation)
- Myasthenia gravis- Weak muscles so greater danger of airway collaspe under sedation.
List some contraindications of IV sedation.
Intracranial pathology- You need to monitor how alert the patient is and sedation interferes with this.
Myasthenia gravis.
Hepatic insufficency- inabililty to metabolise the drug.
Pregnancy and lactation- drug will pass to the baby.
List some contraindications of inhalational sedation.
Blocked nose
COPD
Pregnancy
Enlarged tonsils or adenoids- they will be natural mouth breathers.
List some dental contraindications of sedation:
- Spreading infection.
- Procedure too long (sedation will wear off)
- Procedure too traumatic.
What is ASA 1 classification .
Normal Healthy patient (non smoker/minimal alcohol)
What is ASA 2 classification .
Mild systemic disease or well controlled (e.g. current smoker/well controlled epilepsy)
What is ASA 3 classification .
Severe systemic disease which limits activity but is not incapacitating.
SWhat is ASA 4 classification .
Severe systemic disease that is a constant threat to life.
What ASA classifications can be treated with sedation without an aesthetist.
ASA 1 and 2
What social history are we assessing before Sedation/ GA
- Occupation- are they able to work the day after sedation.
- Responsibilities- are there other people they are responsible for
- Escort-Who can accompany them to the appointment
- Transport- how will they get to and from the appointment
- Alcohol intake- don’t want them drinking when they come in for sedation.
- Smoking- do they smoke?
- Fears- phobia/anxiety/
How do most drugs affect medazolam?
They increase the sedative effect.
What is a pharmacodynamic interaction and which drugs do this?
Interactions between drugs which have similar or antagonist pharmacological effects or side effects
Antidepressants and benzodiazepines.
Antihypertensives and benzodiazepines.
What is a pharmacokinetic interaction ?
When one drug alters the absorption/distribution/metabolism/excretion of another.
Why is it vital to know about any of the patient’s respiratory problems .
As sedation can cause respiratory depression.
What vital signs do we check when assessing a patient for Sedation?
- HR
- BP
- O2 Saturation
- BMI
What is the BMI cutoff for sedation?
35
What is an underweight BMI?
<18.5
What BMI means the patient is a healthy weight.
18.5-24.9
What BMI means the patient is obese?
>30
What BMI means the patient is overweight.
25-29.9
Why do we avoid overcomplicated treatments for sedation treatment plans?
As the sedation will only last 45 minutes.
How do Benzodiazepines work?
Acts on receptors in CNS to enhance the effect of GABA. This prolongs the time for receptor repolarisation of the cerebral cortex and motor circuits.
i.e. the longer to repolarise- so takes longer to register the pain.
Describe the effects of benzodiazepines on respiration.
Respiratory depression:
- CNS depression and muscle relaxation.
- Decrease in cerebral response to increased O2 (Primary driver for breathing)
- Synergistic relationship with other CNS depressants.
- Increased respiratory depression in already compromised patients.
Describe the effects of benzodiazepines on Cardiovascular.
Muscle relaxation decreases vascular resistance which decreases the BP.
Baroreceptor reflex compensates for the BP fall by increasing the HR.
What drugs do benzodiazepines interact with?
CNS depressants.
Erythromycin
Antihistamines
Antihypertensive
Antidepressants.
What can we use for IV sedation and why?
Midazolam-
- A water soluble drug which makes it painless on injection.
- It has rapid onsent (2-3 times more potent than diazepam)
- Short elimination half life (less working time but safer as patients are sedated for less time)
- Metabolised in the liver.
Porphylol
How many people are needed to sedate a patient?
2 trained people in the room at all times and a 3rd person who acts as a runner.
How do we adminster IV sedation
We use an indwelling canula (as it need sto stay in while we carry out the treatmenent- this might be needed for emergency treatment)
What are the two most used sites for canulation?
Dorsum of the hand
Cubital fossa.
Discuss the advantages & disadvantages of the Dorsum of the hand for cannulation.
Adv
- good access
- No nearby arteries
- No nearby nerves
- No joints .
Disadv-
- Smaller veins
- Suceptible to cold and anxiety
- Veins are mobile
- Veins are more painful.
Discuss the advantages & disadvantages of the cubital fossa for cannulation.
Adv-
big well tethered veins
less painful
Less venoconstruction
Disadv-
More difficult access
Risk of nerve damage or potential intraarterial injection.