special care Flashcards
what is the definition of conscious sedation
a technique in which the use of drug produces a state of depression of the central nervous system enabling treatment to be carried out, with verbal communication maintained
loss of consciousness unlikely
what are the 4 types of conscious sedation
inhalation
intra venous
oral
intranasal - not widely available
what is assessed pre-conscious sedation
thorough MH, SH
airway assessment - neck size/posture/mallampati score
- height, weight, BMI
- heart rate, BP, SpO2
what consent is needed for conscious sedation
written
what are the 3 standard techniques of conscious sedation
inhalation alone
IV with single drug by single route
oral with single drug by single route
what is used for inhalation sedation
nitrous oxide and oxygen
how is inhalation sedation delivered
gas via nose piece mask
what anxiety levels is IHS used for
mild
what is required by pt for IHS
ability to breathe through nose
what effects does IHS have
anxiolytic
analgesic
what is the brand name for nitrous oxide
entonox
what kind of gas is nitrous oxide
sweet smelling
colourless
heavy
what are the properties of nitrous oxide
rapid onset of action (3-5 mins)
crosses blood-brain barrier rapid
elimination rapid
no hangover effect
what are signs of IHS overdose
headache
nausea
vomiting
what can IHS overdose cause
diffusion hypoxia
how do you treat IHS overdose
reduce dose
O2 flush
what is diffusion hypoxia
when nitrous oxide is discontinued, it leaves the blood more quickly than nitrogen from the air is absorbed
leads to dilution of oxygen in the lungs
causes hypoxia
how is diffusion hypoxia prevented
administer 100% oxygen after cessation of nitrous oxide for 5 minutes
what are the indications for IHS
mild anxiety
needle phobia
pt not suitable for IV/GA
straightforward dental tx
what should be considered before IHS
ability to cooperate:
- age
- learning disability/cognitive impairment
- ability to tolerate mask
what are IHS contraindications
copd
recent eye or ear surgery
mask intolerance
pregnancy
vit b12 deficiency
methotrexate intraction
chemo
what equipment is required for IHS
RA machine
gas cylinders or piped gas
scavenging
what drug is used for IV sedation
midazolam
what anxiety levels would IV sedation be used for
mild-moderate
what effect does midazolam have on memory
amnesia
what is the reversal drug for midazolam
flumazenil
what are the indications for IV sedation
dental anxiety/phobia
medically suitable
social history
unpleasant procedures
what are the contraindications for IV sedation
needle phobia
medical reasons
social reasons
pregnancy
poor venous access
what equipment is required for IV sedation
midazolam
flumazenil
syringes & labels
saline
pulse oximeter
BP cuff and machine
tourniquet
what is the concentartion of midazolam
1 mg/ml
what is the concentration of flumazenil
500 micrograms in 5 ml
what would stop pulse oximeter from being accurate
dark nail polish/gel or acrylic nails
finger tapping/playing with pulse oximeter
what are signs of IV overdose
loss of protective reflexes
loss of consciousness
decreased respiration
decreased heart rate
what kind of drugs midazolam and flumazenil
benzodiazepine
what is oral sedation
midazolam delivered as a drink
what must also be done for oral sedation
cannulation - for reversal
what is a premed
preliminary administration of a drug preceding a procedure, as an antibiotic or antianxiety agent
give an example of a drug regimen for premed with diazepam
5-10mg diazepam
taken last thing at night and on wakening morning of appt
60-90 mins before appt
what are the drug interactions with diazepam
antibacterials - rifampicin
antivirals - ritonavir
proton pump inhibitors - omeprazole
what are the indications for diazepam premed
very anxious patients
pts when sedation is contraindicated
more complex and prolonged procedures
what are contraindications for diazepam
hepatic impairment
renal impairment
pregnancy
breast feeding
what are cautions for diazepam
avoid prolonged use
reduce dose in debilitated pts
reduce dose in elderly
respiratory disease
what is an alternative premed to diazepam
temazepam
what effects can benzodiazepines have
anxiolytic
anticonvulsant
sedation
amnesia
muscle relaxation
why do benzodiazepines cause muscle relaxing
central effect:
depression of spinal reflex activity
what are short term side effects of benzodiazepines
drowsiness
dizziness
reduced concentration & coordination
hypotension
respiratory depression
sexual fantasy
what are the long term side effects of benzodiazepines
tolerance
dependence
withdrawal symptoms
where would you get sedation standards and guidance
IACSDS
intercollegiate advisory committee for sedation in dentistry standards
SCDEP - conscious sedation in dentistry
what is the definition of general anaesthesia
state of controlled unconciousness with loss of protected reflexes
what are the indications for GA
lengthy or complex surgery
very anxious and unable to tolerate concious sedation
profound learning disability
multiple XLA in multiple quadrants
severe trauma or acute infection
when conscious sedation is contraindicated
what are the advantages of GA
cooperation not required
pt unaware of procedure taking place
significant amount of tx can be carried out in one visit
may be able to coordinate interventions with other specialities
what are the disadvantages/limitations of GA
needs careful tx planning
tx has to be more radical to be done in one visit
open consent needed as tx plan can change
doesnt help pt get over fear #
hospital admission required
pre-op fasting and after care
risk of morbidity and mortality
what is the only place GAs can be administered
hospital with intensive care facillites
what is deep sedation
nearly unconscious, only has purposeful response to repeated and painful stimulation
what is sedation used to achieve
get pt relaxed enough to allow tx to proceed safely and with minimal physiological and psychological stress
what are general indications for sedation
anxiety and phobias
prolonged or traumatic procedures
bad gag reflex
medical conditions aggravated by stress
special care
why is conscious sedation safe
pt is conscious - communcation maintained
pt spontaneosuly maintains own airway
cario-respiratory fucntion is normal
what happens after IV injection
rapid rise in plasma level
drug passes through R side heart, pulmonary circulation and the L side heart
goes to brain via arterial system
effects start once crossed blood-brain barrier
what is the hand-heart-brain circulation time
25 seconds
what is a non-barbiturate sedation drug
propofol
what are the 2 ways a pt recovers from sedation
- redistribution of the drug from CNS into body fat
- uptake and metablosim of drug by liver and elimination by kidneys
what is redistribution responsible for after sedation
intial recovery, the alpha hald-life, time taken for serum conc to drop by 50%
what is elimination responsible for after sedation
beta half-life, time taken to remove half the drug from the body
what are the differences in benzodiazepines due to
affinity for receptors (potency)
half life
active metabolites
describe the mechanism of action of benzodiazepines
gamma aminobutyric acid
endogenous inhibitory neurotransmitter
GABA controls synaptic flow of chloride ions
activation of the benzodiazepine receptors enhances the flow of chloride ions
what happens when chloride ions enter the cell
resting membrane potential more negative
more difficult to fire an action potential so reduces:
- polysynaptic transmission
- depressing uptake of sensory information
is diazepam soluble in water
no
what is the half life of diazepam
30 hours
why is diazepam no longer used for IV sedation
the organic solvent caused vein damage, pain, thrombophlebitis, skin ulceration
what is the issue with diazemuls
long half life and possibility of rebound sedation
is midazolam water soluble
yes
what is the pH of midazolam
<4
describe the administration of midazolam
2-2.5mg 5-10 mins before procedure at 2mg/min, increase steps of 1mg if required
usual total dose is 3.5-5mg
maximum 7.5mg per course
what is the current limit of midazolam on clinic
10mg
describe administration of midazolam for elderly ppl
initially 0.1-1mg 5-10 mins before procedure at 2mg/min
increase in steps of 0.5-1mg
3.5mg max per course
what happens to midazolam when it enters the bloodsteam
becomes lipid soluble at physiological pH
what is the elimination half-life of midazolam
1.9 hours +/- 0.9 hours
where is midazolam metabolised
rapidly in liver but some in bowel
what active metabolite does midazolam produce
alpha-hydroxymidazolam
what is the half life of alpha-hydroxymidazolam
1.25 hours +/- 0.25 hours
what can happen shortly after midazolam injection
laryngeal reflexes dulled
what can rapid injection of midazolam cause
respiratory depression and apnoea
what happens every time you add an increment of midazolam
the half-life starts again with that dose increment and a dangerous accumulation can build up
what 4 drugs interact with midazolam
antibiotics - cins
antivirals - avirs
antifungals - azoles
anticancer- ibs
what are side effects of midazolam
vomiting
skin reactions
what are 2 precautiosn for midazolam
cardiac disease
debilitated patient (children)
what are 3 contraindications for midazolam
CNS depression
compromised airway
severe respiratory depression
what can benzodiazepines cause in pregnancy
neonatal withdrawal symptom
late pregnancy - neonatal hypothermia, hypotonia, respiratory depression
small amount present in breast milk, avoid for 24 hours
what are the guidelines for use of benzodiazepines in hepatic/renal impairment
mild/moderate hepatic - advised caution
severe hepatic - avoid
renal - advised caution due to risk of increased cerebral sensitivity
why is caution needed for midazolam in elderly
altered drug distribution:
- lower total body water
- increased body fat
- decreased serum albumin
- altered hepatic metabolism
- altered renal excretion
what is the half life of flumazenil
50 minutes
how does flumazenil work
has a higher affinity for the benzodiazepine receptor than vitrually all known active drugs
how is flumazenil adminitsred (dose)
200 ug bolus and wait 1 min
increments of 100 ug every minute until pt fully recovered
how much flumazenil can be given in one dose
500 ug
what is the maximum dose of flumazenil
1mg
what is propofol
aqueous white emulsion with rapid onset, clearance, distrubiton and metabolism
what is the half life of propofol
distribution 2-4 mins
elimination 30-40 mins
what are the problems with propofol
pain on injection
expensive
narrow margin of safety
not licensed for dentists to use
what does propofol interact with
alcohol
LA
anti-hypertensives
anxiolytics
CBD
what are contraindications for nitrous oxide
1st trimester pregnancy
copd
vit b12 deficiency
history of substance abuse
methylenetetrahydrofolate reductase deficiency
mental health conditions
name 2 topical anaesthetics creams
EMLA
ametop gel
what is emla cream
2.5% lidocaine
2.5% prilocaine
what is ametop gel
4% amethocaine(tetracaine)
can you use ametop gel in pregnancy
no
how many problem drug users in scotland
72000
how much does drug users cuase per year
2.6bn
5 most common drugs in scotland
cannabis
cocaine
ecstasy
amphetamines
heroin
what % scottish adults use cocaine
3.8
what does cocaine + alcohol cause
cocaethylene
what does cocaetheylene do to the body
makes u 24x more likely to have heart attack
name 5 stimulants
caffeine
nicotine
cocaine
amphetamines
ecstasy
name 5 depressants
alcohol
solvents
heroin
morphine
benzodiazepines
name 3 hallucinogens
LSD
magic mushrooms
cannabis
how many deaths per year from drug abuse
500
how many deaths per year from alcohol
5-250000
how many deaths per year from smoking
100,000
what are the 2 main statures relating to drugs in the UK
the medicines act 1968
misuse of drugs act 1971
what are 5 class A drugs
heroin
cocaine
methamphetamine
ecstasy
methadone
name 2 class B drugs
amphetamines
cannabis
name 3 class 3 drugs
benzodiazepines
ketamine
anabolic steroids
what is heroin a derivative of
morphine
how much more potent is heroin than morphine
4x
what are the positive effects of opiates
initial euphoria
removal of tension
tranquility
sense of control
detachment from worries & fears
analgesia
what are the negative effects of opiates
itching
flushing
myosis
appetite suppression
slurred speech
slow gait
depression
constipation
what health problems come with risky behaviour
unwanted pregnancy
death
STDs
assault
BBV’s
what health problems are associated with injecting
BBVs
DVT
collapased veins
amputation
abscesses
what mental health problems are associated with drug use
paranoia
schizophrenia
depression
bulimia/anorexia
bipolar
what is the ffoulds classifications
organic
psychosis
neurosis
personality disorder
eating disorder
what is neurosis
contact retained with reality
what is psychosis
contact lost with reality
give 5 examples of neuroses
anxiety
phobic
obsessional
hypochondrial
depressive
name 2 funtional psychoses
bipolar
schizoprenia
what is schizophrenia
though and emotion disorder
name 3 eating disorders
anorexia nervosa
bulimia nervosa
pica
what are the oral effects of anorexia
ulcers
dry mouth
infections
bleeding
what are oral effects of bulimia
dental erosion
oesophageal stricture
what are oral signs of pica
fractured teeth
dentures
braces
what are 3 ways of breaking the cycle
harm reduction
substitution
prison
what are 3 reasons for homelessness
relationship breakdown
prison
loss of employment
what is methadone
methadone hydrochloride
synthetic opiate analgesic
how does methadone work
action on CNS
continuous occupancy of Mu opioid receptors
stabilizes neurochemistry
where is methadone absorbed
buccal mucosa
stomach
what is the sugar content in normal methadone
50%
70ml = 35g sugar
why do drug misusers have poor oral health
dry mouth
bruxism
sugar craving
sugar in medication
non-attendance
poor knowledge
smoking and alcohol
what is found orally with amphetamines
xerostomia - caries and perio
bruxism - TMD
attrition/erosion
what does ecstasy cause OH wise
bruxism - TMD
occlusal wear on posterior teeth
xerostomia
attrition and erosion
mucosal burns
what does cocaine cause OH wise
xerostomia
caries in unusual surfaces
bruxism TMD
erosion
gingival and tongue erosions
ulceration of palate
cluster headaches
what is the risk of LA after cannabis use
increased risk of tachycardia with adrenaline
what is some methadone specific advice for users
drink with a straw
take near mealtime
swallow immediately
rinse with water after
chew sugar free gum to increase saliva
