Chp 5 Sedation and general anesthetics

• anxiolysis
• –Drug-induced state during which patients can respond normally to verbal commands

• conscious sedation
• the integrity of patient’s airway
• sedation (sleepiness)

• –Patient 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)

• –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
• –Requires more monitoring - done in a hospital setting

–Induced state of unconsciousness together with a partial or complete loss of protective reflexes, including the inability to maintain an airway independently (must be intubated) and respond to physical stimulation (pain free) or verbal command

–Used in general anesthesia where low doses of several drugs, rather than one drug, with different actions are given to minimize adverse events and provide recovery of the protective reflexes within a few minutes of the end of the surgical procedure

• Enteral
• Parenteral
• Inhalational
• Transdermal

Drug administered by a patch or iontophoresis

intravenously (IV) and through inhalation of drugs

a large initial dose must be given and absorption is not predictable

• enteral
• combination inhalation/enteral conscious

Intravenous moderate sedation

• Inhalation sedation
• anxiolysis (anti-anxiety)
• easy adjustment of depth of sedation and rapid recovery

I or II

Benzodiazepines

• –Diazepam (Valium) – irritating at the injection site
• –Midazolam (Versed)
• Less painful injection
• Short acting
• Pregnancy category: D

• –Lorazepam (Ativan)
• –Chlorazepate (Tranxene)
• –Alprazolam (Xanax)
• –Diazepam (Valium)
• -Triazolam (Halcion)

Triazolam (Halcion)

Flumazenil (Mazicon)- a Benzodiazepine antagonist

• Produce mood changes
• Provide analgesia (pain relief)
• Elevate the pain threshold
• Reduce the dose of the intravenous anesthetic
• –Used with benzodiazepines

• Fentanyl (Sublimaze)
• Meperidine (Demerol)

• –Fentanyl (Sublimaze)
• –Sufentanyl (Sufenta)

Naloxone (Narcan)

• Propofol (Diprivan)
• Chloral hydrate (Noctec)

• –Not used in the dental office
• –Rapid induction (40 seconds)
• –Short duration of action (5 to 10 minutes) –Rapid recovery without hangover and nausea and vomiting
• –Combined with an analgesic agent or local anesthetic because by itself it provides no analgesia

• –Sedative/hypnotic with little to no analgesic properties
• –administered orally (not very palatable) or rectally for anxious children before a dental procedure
• –For sedation before and after surgery–Given for conscious sedation, not for general anesthesia
• -Must be careful in calculating and administering proper dose because overdose and death can ocurr easily
• –Readily absorbed with an onset of action of 30 to 60 minutes and duration of action of 4 to 8 hours

Nonhalogenated

• It is a weak general anesthetic agent
• Has marked analgesic (pain free) and amnesiac (loss of memory) properties.
• Helps to allay anxiety to dental treatment for many patients
• Ideal for dental procedures
• Patient remains conscious and can follow instructions while having full analgesia

• rapid onset (2 to 3 minutes)
• 35%

pulmonary alveoli into the bloodstream

• 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

• 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

• B12
• megaloblastic anemia

respiratory depression, bronchodilation, or low blood pressure

• –Chronic obstructive pulmonary disease (e.g., bronchitis or emphysema)
• –Respiratory obstructions (e.g., stuffy nose, blocked Eustachian tubes)
• –First trimester of pregnancy
• –Bowel obstructions

scavenging devices

Analgesia: Reduced pain, reflexes present, respiration regular. Patient is conscious. N2O holds this level. Ends with loss of consciousness

Delirium/Excitement: Irregular respiration, involuntary muscle movement, increased sympathetic stimulation. Patient discomfort. Emesis and incontinence

Surgical anesthesia: Most procedures performed here

Respiratory/Medullary Paralysis: Cessation of all breathing. Circulatory failure. Patient dies if not reversed

• different drugs
• 1st: Premedication
• 2nd: Induction
• 3rd: Maintenance
• 4th: Recovery

Before the patient is in operating room. May include antibiotic, anxiolytic, antiemetic

In the OR, usually done w/IV agent

Phase during which surgery is performed usually handled w/inhaled agent

Begins with end of procedure until patient is fully awake and responsive. Drugs here include pain and/or antinausea meds

• Injectable
• Inhalation

• Intravenous
• inhaled

• halogenated drugs and nonhalogenated drugs
• volatile liquids (turns to vapor when exposed to air) or gases (nitrous oxide is the only gas).

concentration of inhaled anesthetic required to induce surgical anesthesia in 50% of patients

• lipid
• water
• liver/kidney
• lungs
• blood to brain
• blood
• alveoli

• halothane (Fluothane)
• isoflurane (Forane)
• desflurane – (Suprane)
• sevoflurane – (Ultane)

—First halogenated agent (1950’s). Prototypical drug, not used much today.Slower onset and recovery than other agents

• —Widely used agent
• —Good muscle relaxing properties
• —Rapid onset and recovery

• —Widely used for outpatient procedures due to very rapid onset and recovery.
• —Often used in combination with nitrous oxide

Similar to desflurane. Used in same way

induction of anesthesia

• –Use IV and inhaled anesthetics together
• Allows dose of inhaled agent to be reduced
• Fewer adverse side effects
• –More analgesia and muscle relaxation than with inhaled anesthetic alone
• Some are the same drugs that are used for conscious sedation but in different doses

• Sodium thiopental (Pentothal)
• Methohexital sodium (Brevital)

was the primary barbiturate until propofol was introduced

• —Ultra short acting barbiturate (duration of 5 -10 minutes)
• —Rapid onset (20 – 40 seconds)
• —Often used to induce anesthesia and then patient placed on inhaled agent for procedure.
• Anesthesia without analgesia -if used alone, need to use a local anesthetic

• Injectable General Anesthetics
• Used most often for dentistry than other uses
• —Narcotic agent
• —Outstanding post-op analgesia
• —Deep sedative properties

Nausea and vomiting