Commonly Used Drugs in IV Sedation Flashcards
what is ASA I
normal, healthy patient without systemic disease
what is ASA II
mild systemic disease
what is ASA III
severe systemic disease, limits activity but no incapacitating
what is ASA IV
incapacitating systemic disease that is constant threat to life
what is ASA V
not to survive 24 hours with/without operation
what is ASA VI
brain dead patients awaits for organ donation
what is ASA E
emergency operation
what is normal or usual
ability to climb one flight of stairs or walk 2 level city blocks
what is distress
undue fatigue, shortness of breath, or chest pain
describe ASA I
- little or no anxiety patient
- tolerate stress of surgery with no added risk of serious complications
what is ASA II
- extreme anxiety/fear
- distress -> chest pain, shortness of breath
- older (>60 yo)
- pregnant
- green light with caution
what are examples of ASA II patients
- healthy pregnant female
- older than 60 year old patient
- extreme phobic patient
- drug allergy or multiple allergies patient
- systolic 140/159mmHg and diastolic 90-94mmHg
- type II or non insulin dependent diabetes
- well controlled epilepsy (no seizure in the past year)
- well controlled asthma
- hypothyroid/hyperthyroid patient under treatment and currently euthyroid
describe ASA III
- no signs and symptoms of distress at rest, BUT not under stressful situation
- serious treatment modification is needed
- yellow light for treatment (proceed with caution)
what are examples of ASA III patients
- type I DM, well controlled patient
- symptomatic thyroid disease patient
- greater than 6 months without any residual complication: myocardial infarction ,CVA
- BP (169-199) systolic/ (95-114) diastolic
- epilepsy: several seizures per year
what are examples of ASA III patients
- asthma: stress/exercise induced/hospitalization
- angina pectoris (stable angina)
- CHF with: orthopnea ( more than 2 pillow), ankle edema
- COPD: emphysema, chronic bronchitis
describe ASA IV
- signs and symptoms of their medical problem at REST
- their medical problem has greater significance than elective dental treatment
- OK for non invasive dental emergency treatment
- if invasive dental treatment is needed -> hospital
- red light for treatment- dont proceed
what are examples of ASA IV patients
- unstable angina
- less than 6 months without any residual complication: MI or CVA
- BP greater than 200 / greater 115 diastolic
- uncontrolled dysrhythmias
what are examples of ASA IV patients
- severe CHF or COPD: wheel chair bound or need supplemental oxygen
- uncontrolled epilepsy
- uncontrolled IDDM
describe the ASA V patient
- moribound patient not to expect to survive 24 hours
- hospitalized patient with end stage disease
- palliative dental care
what are examples of ASA V patients
- hospital heart valve surgery patients in need of dental extractions
- hospital patients with end stage organ disease in need of palliative dental care
what percentage of patients are ASA I or II
85%
what percentage of patients are ASA III or IV
14%
what is the definition of sedation
reduction of irritability or agitation by administration of sedative drugs, generally to facilitate a medical procedure
what are the types of sedation
- moderate sedation
- deep sedation/general
- site certificate for each type
what are the types of moderate sedation
- enteral
- parenteral
- pediatric
what is the pediatric pt definition
- a pt aged 12 or under
use of preoperative sedatives for children must be avoided due to:
the risk of unobserved respiratory obstruction during transport by untrained individuals
children can become _______ despite the intended level of minimal sedation
moderately sedated
what is minimal sedation
a minimally depressed level of consiousness produced by a pharmacological method, which retains the patients ability to independently and continuously maintain an airway and respond normally to tactile stimulation and verbal command
- cognitive function and coordination may be modestly impaired, ventilatory and cardiovascular functions are unaffected
when the intent is minimal sedation for adults, the appropriate initial dosing of a single enteral drug is:
no more than the maximum recommended dose of a drug that can be prescribed for unmonitored home use
nitrous oxide ______ be used in combination with a single enteral drug in minimal sedation
may
nitrous used in combo with sedative agents may produce:
minimal, moderate or deep sedation or general anesthesia
describe moderate sedation
- a drug inducted depression of consciousness during which patients respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation
- generally no interventions are required to maintain a patent airway and spontaneous ventilation is adequate
- cardiovascular function is usually maintained
describe deep sedation
- a drug induced depression of consciousness during which patients cannot be easily aroused but respond purposefully following repeated or painful stimulation
- the ability to independently maintain ventilatory function may be impaired
- patients may require assistance in maintaining a patent airway and spontaneous ventilation may be inadequate
- cardiovascular function is usually maintained
who are qualified sedation provider
- a currently licensed dentist in missouri with a valid permit to administer enteral, parenteral, or pediatric moderate sedation
- a currently licensed anesthesiologist
- a currently licensed certified registered nurse anesthetist
what are the common meds used in IV sedation
- barbiturate
- propofol
- ketamine
- benzodiazepine
- opiods
what are the desirable effects of opiods
- analgesia
- sedation
- euphoria
- anti-tussive
what are the undesirable effects of opioids
- respiratory depression
- coma
- emesis
- constipation
- histamine release
- potential for addiction
what eye issue can opioids cause
miosis
what is the MOA of opioids causing miosis
- edinger-westphal nucleus of oculomotor nerve
- enhanced parasympathetic stimultion
what is the significance of opioids
most other causes of coma and respiratory depression produce mydriasis (dilation of pupil)
all addicts demonstrate:
pin point pupils
what are the opioid receptors and what do they cause
- Mu:
- M1: analgesia
- M2: respiratory depression
- physical dependence, muscle rigidity
- Kappa: miosis and sedation
- Delta: behavioral response to pain
- Sigma: dysphonia, hallucinations
what is the MOA of opioids
- specific receptors at CNS and other tissues
- endogenous peptides interact with opioid receptors
what are the endogenous receptors that interact with opioid receptors
- endorphins
- enkephalins
- dynorphins
what is the gold standard of pain med
morphine
what is the MOA, onset, half life, duration, of morphine
- IM/ IV
- hyperpolarize nerve cell, decrease release of substance P
- least lipophilic -> minimum crossing to BBB
- onset 5-10 minutes, peak within 30 mins
- Half life: 1.5-2 hours
- duration of action: 4-6 hours
morphine should not be given to:
neonates
what is the metabolism of morphine
- conjugate with glucuronic acid
- morphine-6-glucuronide (potent analgesic)
- morphine-3-glucuronide
what is the elimination of morphine
- end product eliminated by kidney
- renal failure patient may have narcosis and vent failure for days
what is the adverse effect of morphine
- nausea and vomiting: stimulate medullary chemoreceptor trigger zone
- severe respiratory depression: rigid chest syndrome
- histamine release: may lead to profound drop in BP and systemic vascular resistance
fentanyl has ____ potency of morphine
100x
what are the routes of administration, MOA, onset of action, and duration of fentanyl
- Oral/IV/ transdermal
- analgesic and sedative effect
- high lipid solubility -> rapid onset/short duration
- onset of action < 60 sec with peak effect in 2-5 mins
- duration: 30-60 mins
what is the metabolism of fentanyl
- inactive metabolite
- remember the end of the effect is du to redistribution
- fentanyl will accumulate in body fat with repeated injections
what is the elimination of fentanyl
- little effect on renal patient
- clearance dependent on hepatic blood flow
what are the adverse effects of fentanyl
- no histamine release
- rigid chest syndrome
- after large drug bolus
what is the MOA of naloxone
- competitive antagonist at opioid receptors
- greater affinity for mu receptors than Kappa or delta receptors
what is the MOA, duration, and half life for naloxone
- reversal of endogenous or exogenous opioid compound
- rapid antagonizing (1-2 mins)
- brief duration of action (30-45 mins) IV: rapid distribution of CNS
- half life is only 30-80 mins: respiratory depression may linger despite alert/awake appearancew
what is the dosage of naloxone
IV administration of 0.4mg IV (titrate to effect)
what is the recommended usage for naloxone
- any suspicion: support respiration (O2 and continue monitoring), check oxygen saturation, vital signs
- continue sluggish response: rule out hypoglycemic shock, CVA, psychotic episode, consider giving IM, if concern for re-sedation give 0.4mg IM
what are the side effects of naloxone
- abrupt reversal -> excessive catecholamine release: tachycardia, hypertension, ventricular irritability
- may antagonize clonidine
- nausea/vomiting may be observed
benzodiazepines can cause:
- sedation
- anxiolysis
- muscle relaxation
- anterograde amnesia
- anticonvulsant effects
what are the common side effects of benzodiazepines
- fatigue
- drowsiness
- respiratory depression
do benzodiazepines have a direct analgesic effect
no
what is the MOA of benzos
- enhances inhibitory effect of NTs
- facilitates GABA receptor binding
- increases membrane conductance of chloride ions
IM injection of diazepam is:
painful and unreliable
what is the pharmacolgoy of diazepam
- water insoluble
-propylene glycol and sodium benzoate added but pain upon injection - rapid uptake by CNS due to high lipid solubility
what is the metabolism of diazepam
- hepatic microsomal enzyme -> desmethyldiazepam + oxazepam
- desmethyldiazepam is metabolized slowly -> sustained effects
- phase 1 metabolites of diazepam are pharmacological active
what is the elimination of diazepam
30 hours
oral admin of midazolam is ____
not approved by the FDA but commonly used
what is the pharmacology of midazolam
- no local irritation
- 2-3x more potent than diazepam
- water soluble at low pH
- lipid soluble at high pH
- imidazole ring closes at physiologic pH
what is the metabolism of midazolam
hydroxylated in the liver
what is the elimination of midazolam
- conjugated and excreted by kidneys
- short half life -> 2 hours
does midazolam cross placenta
yes
what is an antagonist of benzos
flumazenil (Romazicon)
what is the MOA of flumazenil
competitive antagonist of benzodiazepine receptors
what is the usage of flumazenil
- reversal of benzo sedation and/or overdose
- prompt (less than 1min) hypnotic reversal, amnesia?
- respiratory depression may linger despite alert/awake appearance
what is the dosage for flumazenil
IV administration of 0.2mg every min until reversal
-due to rapid hepatic clearnace, repeat dose may be needed in 1-2 hours
- half life is only 1 hour
what are the side effects of benzos
- may induce seizure activity
- increase catecholamines
- increase BP and heart rate
- nausea and vomiting
what is the most frequently administered general anesthesia induction agent
barbituates
what is the MOA of barbituates
enhance GABA inhibitory NT
what is the site of action of barbituates
- depress reticular activating system
- polysynaptic network responsible for consciousness
what are the common barbituates
- thiopental
- methohexital (brevital)
- phenobarbital
what is the MOA of propofol
- enhance GABA inhibitory function -> increase Cl channel -> hyperpolarization of cell membrane
- results rapid onset of unconsciousness
- arterial and venous dilation
- largely replacing thiopental (barbituates)
describe ketamine
- general anesthesia medicine
- selective NMDA receptor blocker
- dissociative, hallucinogenic and amnesic effect
- sympathomimetic medicine
what are the disadvantages of ketamine
- hallucinogenic
- nightmare emergence
- increase salivary flow
