Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacology > Anaesthetics > Flashcards

Anaesthetics Flashcards

1
Q

what is dental anesthesia

A
  • medical procedure performed by applying drugs that cause loss of sensation
  • local anesthesia: surface anesthetic; regional anesthesia
  • general anesthesia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is local anesthesia

A
  • loss of sensation to limited part of the body without loss of consciousness
  • used for short term dental surgical/medical procedures
  • applied by 5 major routes, route determined by location and amount of anesthesia needed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the mechanism of action of anaesthetics

A
  • act by blocking the entry of sodium ions into the neutron (sodium channel blockers)
  • sodium influx needed for nerves to fire and conduct impulse
  • non-selective blockade
  • both sensory and motor impulses affected
  • sensation and muscle activity decreased temporarily
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are some special considerations for inflamed tissues

A
  • low pH
  • local anesthetic less effective
  • never inject directly into infected, inflamed tissue (eg abscess) because the infection spreads
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are adverse effects of anesthetic

A
  • allergy rare and usually due to additives (sulphites and methylparaben)
  • cardiovascular effects -> hypotension, dysrhythmias
  • prevent adverse events by slow absorption or not inject directly into blood vessel
  • may injure themselves by biting/chewing area in mouth with no sensation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are early signs of adverse events in anesthetics

A
  • CNS stimulation -> restlessness and anxiousness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are later signs of adverse events in anesthetic

A
  • CNS depression -> drowsiness, unresponsiveness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is lidocaine

A
  • also called xylocaine
  • most frequently used injectable local anesthetic
  • 0.5% - 2% solution
  • infiltration, nerve block, spinal, epidural, topical
  • block sodium channels within membranes of neurons and cardiac tissue -> block nerve impulses
  • onset 5-15 minutes for dysrhythmias
  • solution with epinephrine only for local anesthesia not dysrhythmias
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how can lidocaine be applied

A
  • injectable solution: plain (without EPI), with EPI
  • topical: gel 10%, dentipatch (transoral delivery system)
  • also used as a heart antiarrhythmic (intravenous)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

how can mepivicaine be applied

A
  • injectable solution: 2% solution with vasoconstrictor (1:20,000 (54 mg) levonordefrin). 3% plain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is levonordefrin

A
  • less potent vasoconstrictor than epinephrine but is more likely to cause an increase in blood pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is prilocaine

A
  • injectable form: 4% with 1:200,000 epinephrine. 4% plain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is methemaglobinemia

A
  • excessive methemoglobin levels (big word) reduce the amount of hemoglobin that is available for oxygen transport to the tissues
  • cyanotic nails
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is bupivicaine

A
  • injectable: 0.54% solution with epinephrine 1:200,000

- lasts two or three times longer than lidocaine and mepivacaine, up to 7 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are cloves

A
  • natural remedy for tooth pain = oil of cloves
  • numbing effect
  • works well with cavities
  • soak cotton and pack around gums close to painful area
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is anise

A
  • natural remedy
  • oil of anise for jaw pain caused by nerve pressure or gritting of teeth
  • antispasmodic, relaxes intense muscle pressure around jaw angle, cheeks and throat
  • also natural expectorant, cough suppressant, and breath freshener
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the components of local anesthetics

A
  • epinephrine
  • alkaline substances
  • hydrochloride
  • vasoconstrictors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what does epinephrine do in anesthetics

A
  • extends duration of action
  • constricts BV in area -> anesthetic in area longer
  • ie instead of 15-20 mins -> 45-60 min
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what do alkaline substances do in anesthetics

A
  • alkaline substances such as sodium hydroxide or sodium bicarbonate added. neutralizes region, anesthetics more effective in basic environment. note: infected areas become acidified by bacteria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what does hydrochloride do in anesthetics

A
  • most anesthetics are combined with an acid such as HCl to form a salt because it is more stable and soluble (dissolvable) than the free base
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what do vasoconstrictors do in anesthetics

A
  • local anesthetics cause vasodilation. vasoconstrictors added to local anesthetic, constrict the blood vessels in the tissue resulting in a decrease blood flow to the site of injury. slow the absorption of the agent into the bloodstream
  • lower blood levels that decrease the risk of an overdose
  • decrease or prevent bleeding (homeostasis) at the site of infection
  • higher concentrations of the local anesthetic remaining in the nerve for a longer time (increase the duration of anesthetic effect)
  • watch: EPI can cause hypertension followed by hypotension
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are some examples of vasoconstrictors in local anesthetics

A
  • epinephrine: infiltration, mandibular block
  • levonordefrine (neo-cobefrin): fewer cardiac effects but more toxic effects
  • contraindicated in patients taking psychotropic drugs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what can go wrong with too much epinephrine

A
  • excessive cardiac stimulation resulting in angina, cardiac arrhythmias, hypertensive crisis, and stroke
  • in healthy patient EPI has no cardiac effects
  • the maximum safe dose for epinephrine:
  • in healthy individuals is 0.2 mg
  • in cardiac patients is 0.04 mg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what are the concentrations for epinephrine

A
  • available in many concentrations: 1:50,000; 1:100,000 and 1:200,000
  • concentration of EPI is increased from 1:100,000 to 1:50,000,
  • alpha effect for local vasoconstriction increases
  • the systemic beta effect increases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is levonodefrin

A
  • less potent vasoconstrictor than EPI
  • primarily stimulates alpha-adrenergic (sympathetic) receptors with little to no effect on the beta-adrenergic receptors
  • stimulation of alpha-1 receptors on tissues/organs causes vasoconstriction of blood vessels resulting in hypertension (increase systolic and diastolic blood pressure)
  • since it is less effective/potent than epinephrine it is used in higher concentrations (eg 1:20,000)
  • mepivacaine 2% is available with levonordefrine
  • onset of action is fast (30 to 120 minutes in the maxilla and 1-4 minutes in the mandible)
  • duration of action is about 1 to 2.5 hours in the maxilla and 2.5-5.5 hours in the mandible
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

topical forms of anesthetics

A
  • lidocaine: gel, dentipatch
  • benzocaine
  • oraqix periodontal gel: lidocaine/prilocaine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what should be done for anesthetic in children

A
  • primary concern is the ease of overdose
  • before administering a local anesthetic to a child: child’s weight used to calculate the appropriate dose
  • in children under 10 years of age: usually no more than one-half cartridge of lidocaine 2% with epinephrine per procedure
  • best to administer low-concentration solution such as 2% lidocaine with epinephrine 1:100,000
  • bupivacaine should not be used because long duration of action
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what should be done for administering anesthetic for pregnant and nursing patients

A
  • local anesthetics with vasoconstrictors can be used safely in pregnant and nursing women
  • because of its low-concentration, lidocaine is preferred
  • the concentration of vasoconstrictor is low so that there is unlikely any effect on uterine blood flow
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what should be done for administering anesthetic for the elderly

A
  • no documented difference response to local anesthetics with vasoconstrictor – elderly vs younger adults
  • best to administer below maximum recommended doses due to slower metabolism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

how to select the best anesthetic

A
  • selection based on: duration of the dental procedure, amount of time pain control is required
  • short procedure (especially involving mandibular block): solutions without vasoconstrictor such as mepivicaine of prilocaine plain
  • longer procedure: bupivicaine has a long duration of action
  • anticipation of post-op pain; choose a longer duration anesthetic to cover post op pain, like bupivicaine
31
Q

what do we use if epinephrine is contraindicated

A
  • if epinephrine is contraindicated, use mepivicaine or prilocaine plain
32
Q

anesthetic selection for routine procedures

A
  • use of epi is justified for most dental procedures
  • lidocaine, articaine, prilocaine or mepivicaine
  • children and pregnant patients: lidocaine with EPI
33
Q

what are most allergic reactions to in anesthetics

A
  • preservatives
34
Q

what can happen when local anesthetics interfere with the CNS

A
  • crosses the blood-brain barrier

- respiratory failure

35
Q

what are blood disorder concerns for anesthetics and what do we use for them

A
  • methemoglobinemia
  • use priolocaine or
  • articaine, topicals benzocaine
36
Q

how can we treat toxicity caused by anesthetics

A
  • monitor vital signs
  • administer O2
  • emergency operations
37
Q

how can we manage a medical emergency with a cocaine user

A
  • do not administer EPI to a suspected cocaine addict for at least 24 hours after last use
38
Q

how can we manage a medical emergency for a hypertensive patient

A
  • patient taking non-selective beta-blocker (eg propranolol, nadolol) for hypertension
  • limit EPI dose to 2 cartridges (0.04 mg) of 1:100,000
39
Q

how can we manage medically compromised patients in the dental office

A
  • patient taking cardioselective (beta 1) blocker, like atenolol, metoprolol for hypertension is no concern for epi
  • no special precautions for using epi in patients with thyroid disease taking supplements
  • monoamine oxidase inhibitors: antidepressant, ex isocarboxazid, phenelzine. no special precautions
  • asthma/bronchitis: no special precautions using epi
40
Q

what is the dental management of patients with diabetes mellitus

A
  • epinephrine increases blood glucose levels

- caution in uncontrolled diabetics

41
Q

what is the dental management of tricyclic antidepressants

A
  • amitriptyline, desipramine, imipramine
  • block reuptake of NE/EPI
  • use EPI cautiously; no more than 2 cartridges of 1:100,000
  • avoid levonordefrin
42
Q

what is the dental management of blood disorders

A
  • prilocaine is contraindicated in patients with methemaglobinemia
43
Q

what is conscious sedation

A
  • maintains the integrity of patient’s airway
  • sedation (sleepiness)
  • unaware of surroundings (narcosis)
  • amnesia (loss of memory) or analgesia (increased pain threshold without loss of consciousness so the patient still responds to verbal (arousable) and physical stimuli)
  • used in dental office
44
Q

what is minimal sedation

A
  • anxiolysis
  • drug-induced state during which patients respond normally to verbal commands
  • ventilatory and cardiovascular functions are unaffected
45
Q

what is deep sedation

A
  • induced state of depressed consciousness accompanied by partial loss of protected reflexes, including the inability to maintain an airway and/or respond to physical stimulation or verbal command
  • hospital setting
  • use of general anesthetics
46
Q

what is balanced anesthesia

A
  • used where low doses of several drugs rather than one drug, with different actions are given
  • minimize adverse events
  • provide recovery of the protective reflexes within a few minutes of the end of the surgical procedure
47
Q

what are the different routes and types of administration for sedation

A
  • enteral: absorption is through the GI tract (oral, rectal, sublingual)
  • parenteral: absorption bypasses the GI tract (IV, IM)
  • inhalation: gaseous or volatile drug is introduced into the lungs
  • transdermal: drug is administered by a patch or iontophoresis
48
Q

how is general anesthesia obtained

A
  • through IV and inhalation of drugs
49
Q

what is oral moderate sedation

A
  • vie the enteral route
  • common to use
  • accepted by patients
  • disadvantage: large initial dose and absorption not predictable
  • combined moderate sedation via enteral and/or combination inhalation/enteral conscious sedation. more effective than either route used alone
50
Q

what is IV moderate sedation

A
  • via parenteral route
  • IV sedation does not mean dental anesthesia
  • IV sedation is conscious sedation using IV agents
51
Q

what is inhalation sedation

A
  • via inhalation via the lungs
  • nitrous oxide/oxygen
  • advantages – easy adjustment of depth of sedation and rapid recovery
  • however, when nitrous oxide/oxygen is used in a ratio lower than 70:30, it is not as effective
52
Q

what is moderate sedation in dental office

A
  • for apprehensive anxious patients
  • reducing stress response
  • some degree of amnesia
  • not expected to induce depths of sedation that would impair the patient’s ability to maintain the integrity of his or her airway
53
Q

what is the intravenous moderate sedation

A
  • intravenous anesthetics are mainly used for the rapid induction general anesthesia or moderate sedation
  • maintained with an appropriate inhalation drug such as nitrous oxide-oxygen, or by intermittent or continuous infusion
  • administered first to allay anxiety and fear
54
Q

what are intravenous anesthetics

A
  • administered intravenously (directly into the blood)
  • benzodiazepines take a few minutes to get to brain
  • barbiturates take a few seconds
  • benzodiazepines: diazepam (Valium), midazolam (Versed). amnesia effect and reducing apprehension and fear
  • sedatives: barbiturates
  • pentobarbital may also be used if the patient cannot take benzodiazepines
  • sedative /hypnotics: nonbarbiturates such as propofol (Diprivan)
55
Q

what are IV moderate sedation drugs

A
  • narcotic analgesics
    fentanyl (sublimaze, duragesic, abstral, fentora, generics)
    meperidine (demerol, generics)
  • analgesia (pain control) and euphoria & decrease benzo.
  • varied responses in patients
  • assess individual requirements
  • provider must be prepared to intervene to rescue a patient’s airway
56
Q

when are oral agents used and what kinds are there

A
  • for the fearful and apprehensive dental patient
  • benzodiazepines:
  • lorazepam (Ativan)
  • midazolam (Versed)
  • alprazolam (Xanax)
  • diazepam (Valium)
57
Q

what is chloral hydrate

A
  • sedative/hypnotic with little to no analgesic properties.
  • safe drug when administered both orally or rectally for anxious children before a dental procedure.
  • for sedation before and after surgery.
  • given for conscious sedation and not for general anesthesia.
  • sudden death can occur due to cardiac arrest
58
Q

how can we monitor patients during anesthetics

A
  • important for the safety of patient
  • recognize adverse reactions and emergencies
  • assess patient for adequate airway and gas exchange and cardiovascular response
  • vital signs
59
Q

what are some reversal agents

A
  • benzodiazepine: flumazenil (Anexate) is a benzodiazepine antagonist and is given to patients to reverse the action of a benzodiazepine in cases of overdose.
  • narcotics: naloxone (Narcan) is used in cases of narcotic overdose.
60
Q

what is nitrous oxide

A
  • nonhalogenated
  • first discovered in 1783 by Joseph Priestley
  • laughing gas
  • horace wells was the first dentist to use nitrous oxide
  • it is a weak anesthetic agent with marked analgesic (pain-free) and amnesia (loss of memory) propertie
  • stage I surgical anesthesia
  • helps to allay anxiety to dental treatment for many patients
  • ideal for dental procedure; patient remains conscious and can follow instructions while having full analgesia
  • nitrous oxide has a rapid action (2 to 3 minutes) without loss of consciousness and a rapid recovery
  • the average patient requires 35% of nitrous oxide in oxygen with a range of 10-50%
    50% mixture in oxygen for analgesic
  • easy to administer and can be self-delivered by the patient using the demand-valve positive pressure method
  • used in balanced anesthesia
61
Q

what are indications for using nitrous oxide

A
  • fearful, anxious patient
  • cognitively, physically, or medically compromised patient
  • gag reflex interferes with oral health care
  • when profound local anesthesia cannot be obtained or tolerated
62
Q

what are adverse effects of nitrous oxide

A
  • nausea, vomiting
  • avoid heavy meal 3 hours before
  • chronic exposure
  • fall in the white-cell count and neuropathy (nerve damage including numbness of limbs)
  • exposure of anesthetists or other operating room personnel to nitrous oxide should be minimized
63
Q

what are side effects of nitrous oxide

A
  • adverse events uncommon if low to moderate doses
  • signs of stage 2 anesthesia (anxiety, excitement, combativeness) as dose increases
  • temporary difficulty breathing at end
  • nausea and vomiting following procedure
  • subject to abuse (relaxed, sedated state)
64
Q

what are some possible drug interactions for nitrous oxide

A
  • nitrous oxide interacts with vitamin B12, resulting in megaloblastic anemia
  • additive sedative effect with other sedative drugs and St. John’s wort
  • does not cause respiratory depression, bronchodilation, or low blood pressure
65
Q

what are contraindications for nitrous oxide

A
  • no significant clinical drug interactions occur with nitrous oxide.
  • do not use in patients with the following conditions:
  • coronary heart disease
  • chronic obstructive pulmonary disease (e.g., bronchitis or emphysema)
  • respiratory obstructions (e.g., stuffy nose, blocked Eustachian tubes)
  • pregnancy
66
Q

what are some hazards to operating room personnel regarding nitrous oxide

A
  • faulty equipment can pose a hazard for dental/medical clinicians in the room, especially spontaneous abortion and genetic effects
  • scavenging devices are necessary to avoid exposure of gas to the surrounding clinicians
67
Q

what should we be teaching clients regarding anesthetics

A
  • topical anesthetics, avoid touching eyes
  • never apply topical meds to large patches of skin or to open lesion/cut
  • inform dentist if had adverse rxn in past
  • not to eat/drink until anesthetic worn off
  • do not chew or pick at area while still numb
  • do not inhale anesthetic topical sprays
  • after local, immediate assistance if drowsy, confused, blurred vision, lightheadedness, irregular heartbeat, feeling faint
  • risk if pregnant, seizures, other meds
  • have someone assist/drive after procedure
  • follow caregivers instructions after anesthesia
  • have sufficient pain meds to treat Sx after procedure
68
Q

what is the dosing of articaine in children

A
  • 5mg/kg
69
Q

what is the dosing of bupivicaine in children

A
  • 2 mg/kg
70
Q

what is the dosing of lidocaine in children

A
  • 7 mg/kg
71
Q

what is the dosing of mepivicaine in children

A
  • 6.6 mg/kg
72
Q

what is the dosing of prilocaine in children

A
  • 8 mg/kg
73
Q

converting lbs to kg

A
  • 1 lb = 2.2 kg

Pharmacology (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions