Chapter 9

Question 1

What is “sedation dentistry” and why has it become popular?

Answer 1

It trys to combat dental anxiety

Question 2

What types of sedation are used in most general dental practices? Which ones are reserved for the hospital?

Answer 2

minimal sedation: normal responses to commands but reduced cognition and awareness of surroundings.

Moderate Sedation: amnesia, sleepiness, narcosis, analgesia (sometimes). Fewer risks of respiratory depression than general anesthesia.

Hospital

Deep Sedation: consciousness is depressed, patient does not respond without stimulus. Requires respiratory, cardiac and blood pressure monitoring.

General Anesthesia: Loss consciousness, cannot maintain airway without intubation, often relies on additive or synergistic combinations of anesthetics.

Question 3

By what routes can sedatives be administered? Which ones are administered by each route?

Answer 3

Oral: moderate sedation enteral ( use digestive system)
Inhalation moderate sedation: parenteral (by pass the digestive system, no first pass)
Combined moderate sedation: Enteral and parenteral
Intravenous moderate sedation: parenteral

Question 4

What is the common suffix for benzodiazepines?

Answer 4

AM

Generally category D and X drug

Question 5

Why might your patients be using benzodiazepines (other than for dental treatment)?

Answer 5

Generalized anxiety disorder
Insomnia
Epilepsy
Muscle spasms
Alcoholism

Question 6

What are the pharmacokinetic properties of benzodiazepines in general?

Answer 6

• Absorption : Lipophilic (oral or IV)
• Distribution: crosses blood-brain barrier and placenta, stored in adipose tissues, leads to longer duration, it accumulates with repeated admin higher blood levels over time.
• Metabolism: phase II only or Phase I then II.
• Excretion: Renal routes- active drug, active metabolite or inactive metabolites.

Question 7

Which benzodiazepines differ from the general pharmacokinetics for benzodiazepines? How do they vary?

Answer 7

Diazepam (Valium): Metabolized by phase I enzymes. affected by drug interactions and impaired hepatic function.

Loraepam (Ativan): Metabolized by phase II enzymes, better for those who are elderly or impaired hepatic functions.

Question 8

What is the mechanisms of action for benzodiazepines?

Answer 8

It stimulates GABA binding to CL- channels

Question 9

How do benzodiazepines work pharmacologically?

Answer 9

• Behavioral effects: calming; reduces anxiety and panic. Drowsiness and sedarion at higher doses; decrease in REM sleep in favor of deeper levels. Sleep aids (Zolpidem/Ambien
• Anticonvulsant effects: increase seizure threshold due to CNS depression, it helps prevent its seizure spread to further tissue beyond site of initiation.
• Muscle relaxation: in skeletal muscles

Redcues action potentials due to neurons becoming hyperpolarized (-)

Question 10

What are the common adverse reactions of benzodiazepines? Which ones are particularly important for dental practitioners?

Answer 10

• CNS depression: lethargy, muscle weakness
• Paradoxial CNS stimulation: anxiety,nervousness, hyperactivity can increase.
• Amnesia: several hours after admin of drug
• Respiratory despression : rare but more common in elderly
• Cardiovascular
• Visual effects
• Allergic reaction: common skin reaction

Dental Effects:
* Xerostomia or increased salivation
* Swollen tongue
* Metallic/bitter taste

Question 11

How likely is it that benzodiazepines will be abused?

Answer 11

rarely occurs in patients with anxiety disorders who do not have current or past substance misue problems

Question 12

Which types of drug interactions are important to consider when patients are given benzodiazepines?

Answer 12

• Those that use phase I metabolism:
  Inhibitors:Ciprofloxacin (Cipro), Metoprolol (Toporl XL) SSRIS
  Inducers: Tobacco, rifampin, st. Johns wort

General meds
* Levodopa (Reduce effect)
* Phenytoin ( increased)
* Provenecid (increased)
* Alcohol ( increased benzo effect)

Question 13

Why aren’t barbiturates used often in dental practices? When might they be the best alternative?

Answer 13

due to their high risk of addiction, potential for severe side effects like respiratory depression, and a narrow therapeutic index (toxic dose is small)

Question 14

What other sedatives/hypnotics are available for sedation dentistry?

Question 15

How are insomnia agents being used for conscious sedation?

Answer 15

Works on the same receptors as benzodiazepines

1. Zolpidem (Ambien)
2. Eszopiclone (Lunesta)

Question 16

Which sedatives are good for healthy patients? Pregnant patients? Children? Elderly patients?

Answer 16

Healthy: Fast on set and short half-life: Diazepam/ Valium.

Elderly: Drugs that do not metabolized by phase 1 enzymes (Lorazepam/ Ativan)

Pregnant: Non-benzodiazepine drug (typically barbiturates or propofol) cat C meds.

Children: Midazolam (Versed) or Chloral hydrate (Noctec)

Question 17

How can overdoses of sedatives be treated in the office? Which medications are required for treatment?

Answer 17

Overdose of benzodiazepines or related drugs can be revered with FLUMAZENIL (Mazicon)

Narcotic overdose can be treated with NALOXONE/NARCAN

Question 18

What properties of nitrous oxide make it a good anesthetic for use in dentistry?

Answer 18

nitrous oxide because it slows down the body response to pain signal.

Question 19

Why is oxygen administered before nitrous oxide treatment? After?

Answer 19

when nitrous oxide is discontinued, it can rapidly leave the body, causing a temporary lack of oxygen in the lungs called hypoxia.

Question 20

For what conditions is nitrous oxide contraindicated?

Answer 20

• cognitive impairments
• COPD
• Upper respiratory obstruction
• Pregnancy