Transcript
5
Sedation and General Anesthetics
Educational Objectives
After reading this chapter, the student should be able to:
1. Summarize the concepts of minimal, moderate, and deep sedation.
2. List various pharmacological agents used for moderate sedation.
3. List the objectives in using sedation to manage dental patients.
4. Discuss the role of nitrous oxide in the dental office.
Lecture Outline
I. Terminology
A. Minimal sedation.
B. Moderate sedation/analgesia (new term for conscious sedation).
C. Deep sedation.
D. General anesthesia.
E. Balanced anesthesia.
II. Routes of Administration
A. Enteral.
B. Parenteral.
C. Inhalational.
D. Transdermal (e.g., fentanyl, pain control for cancer patients).
III. Moderate Sedation
A. Goal.
B. Objective.
C. Drugs.
1. Benzodiazepines.
a. Diazepam.
b. Midazolam.
2. Narcotics (e.g., fentanyl).
3. Barbiturates.
4. Nonbarbiturates (e.g., propofol).
D. Patient physical status classification: ASA IIV, E.
E. Intravenous moderate sedation.
1. Rapid induction.
2. Narcotics.
3. Benzodiazepines.
4. Propofol.
F. Oral minimal/moderate sedation.
1. Benzodiazepines.
2. Chloral hydrate.
G. Reversal agents
1. Naloxone, narcotics.
2. Flumazenil, benzodiazepines.
H. Monitoring.
1. Respiratory.
2. Cardiovascular.
I. Sequence of administering conscious sedation.
IV. Nitrous Oxide, Prototype Drug
A. Only gas used routinely for stage I anesthesia.
B. Indications.
1. Fearful, anxious patient.
a. Cognitively, physically, or medically compromised patient.
b. Gag reflex interferes with oral health care.
c. When profound local anesthesia cannot be obtained or tolerated.
2. Objectives.
a. Reduce or eliminate anxiety.
b. Raise pain reaction threshold.
c. Increase tolerance of long appointments.
d. Reduce gagging.
3. Method of administration, inhalation.
4. Adverse effects.
a. Nausea.
b. Vomiting.
c. Fall in WBC.
d. Neuropathy.
e. Interaction with B12.
f. Additive sedative effect with St. John’s wort.
5. Contraindications.
a. Chronic obstructive pulmonary disease (COPD).
b. Upper respiratory infections.
c. Pregnancy.
d. Patients with drug-seeking behavior.
6. Precautions.
a. Fail-safe systems.
b. Scavenger systems.
7. Abuse potential.
V. General Anesthesia
A. History.
B. Indications.
C. Stage of anesthesia, Guedel’s signs.
1. Premedication.
2. Induction
3. Maintenance
4. Recovery
D. Classification of general anesthetics.
1. Intravenous.
a. Barbiturates.
b. Nonbarbiturates.
c. Narcotics.
d. Dissociatives.
e. Muscle relaxants.
2. Inhalational.
a. Gasses.
b. Volatile liquids.
i. Liquid at room temperature.
ii. Convert to a vapor and inhale.
iii. Common volatile agents.
(a) Halothane. (b) Enflurane. (c) Isoflurane. iv. Depress cardiovascular and respiratory functions.
v. Administered by anesthesiologist, CRNA.
vi. Postoperative problems.
vii. Therapeutic uses.
Teaching Tips
1. Stress the importance of obtaining a complete medical and drug/herbal history on a patient before any type of sedation, including nitrous oxide, is used.
2. Explain the importance of learning the ASA classification of patient physical status.
3. To make it easier for students to conceptualize, have a chart classifying drugs used in oral and intravenous moderate sedation and inhalational anesthetics.
4. Have students go into the clinic and demonstrate the use of nitrous oxide.
5. Assign each student an anesthetic to report on. Reports should include classification of anesthetic, route of administration, contraindications, precautions, and side effects. Allow time in class to share information with others.
Factoids
1. In 1790, Humphrey Davy noted that inhaling nitrous oxide made him want to laugh, thus giving rise to the name “laughing gas.”
2. Nitrous oxide was made a usable anesthetic by Colton in 1863. Edmund Andrews, a Chicago surgeon, was the first to use nitrous oxide with oxygen.
Discussion Questions
1. Identify the four stages of general anesthesia.
2. Discuss the ASA classification of patient physical status and its association with dental patients.
3. Discuss the pharmacology of nitrous oxide.
4. Discuss contraindications for using nitrous oxide.
5. Discuss the options for oral and IV moderate sedation for the dental patient.
Classroom Activities
1. Have each student make drug cards for each classification of moderate sedation (e.g., benzodiazepines, narcotics) and reversal drugs. Allow time to review in class.
2. Have students visit www.medscape.com and search for “moderate sedation.” Have students choose different topics and present them to the class.
3. Show a video on the use of nitrous oxide in the dental office.
4. Develop a matching exercise where students match the drug with the correct type of moderate sedation or general anesthesia.
5. Invite an anesthesiologist or nurse anesthetist to speak on administrating general anesthetics.
© 2013 by Education, Inc.
Weinberg, Instructor’s Resource Manual for Oral Pharmacology for the Dental Hygienist, 2nd Edition
