1. Anesthesia and Pain Control
Chapter 37
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 1

2. Fig. 37-1 Topical anesthetic. (Courtesy of Premier Dental Products.)
Some topicals come in little jars. The dental assistant uses a cotton-tipped applicator to place the gel on the oral mucosa.
After administration of both the topical and the local anesthetic, be sure to thoroughly rinse the patient’s mouth; even a small drip of local anesthetic holds a bitter taste and excess topical anesthetic may temporarily cause an uncomfortable numbness of the throat.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 2

3. Chapter 37 Lesson 37.1
Pain is one of the most feared aspects related to dentistry and one of the top reasons for avoiding dental treatment.
Adequate and appropriate anesthesia and pain control for the patient during a dental procedure will make the delivery of dental treatment much easier and less stressful for the dental team, as well as for the patient.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 3

4. Learning Objectives Pronounce, define, and spell the Key Terms.
Discuss the importance of pain control in dentistry.
Describe the composition and application of topical anesthetics.
Demonstrate the placement of a topical anesthetic agent.
(Cont’d)
Patients may not be able to judge the caliber of dentistry delivered, but they are able to relay whether they experienced pain or discomfort.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 4

5. Learning Objectives
(Cont’d)
Discuss the composition and application of local anesthetic agents.
Demonstrate the preparation and management of the setup of a local anesthetic.
Assist during the administration of local anesthesia.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 5

6. Anxiety and Pain Control
A technique of various psychological, physical, and chemical approaches to prevent and treat preoperative, operative, and postoperative anxiety and pain
What is an example of a psychological method to help prevent and treat pain and anxiety before, during, and after a dental procedure? (Talking with the patient in a calm, gentle, and caring manner while addressing any questions about the anesthesia and procedure.)
What is an example of a physical approach? (Gentle handling of the patient, avoiding fast, unexpected movements.)
Providing a patient with a painless dental experience will make future appointments more pleasant.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 6

7. Methods of Pain Control
Anesthetic agents
Inhalation sedation
Antianxiety agents
Intravenous (IV) sedation
General anesthesia
Anesthetic agents include topical anesthetics (jelly) and local anesthetics (injectables).
Nitrous oxide and oxygen are the most common inhalation sedatives, but antianxiety medications may also be prescribed to be taken by mouth before the dental procedure.
Medications may also be administered IV alone or IV in combination with inhalation agents to provide deeper levels of analgesia and anesthesia.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 7

8. Topical Anesthesia
Provides a temporary numbing effect on nerve endings located on the surface of the oral mucosa
Supplied as:
Ointments
Liquids
Sprays
The most commonly used topical anesthetic is a jellylike ointment, usually 20% benzocaine.
Must be left on long enough to effectively permeate the oral mucosa before injectionof a local anesthetic.
What step helps promote effective penetration of the topical anesthetic? (Drying the membranes with the use of gauze to avoid dilution.)
Sprays are sometimes used in patients with severe gag reflexes.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 8

9. Local Anesthesia
The agent most frequently used for pain control in dentistry
Characteristics/advantages
Is nonirritating to the tissues in the area of the injection
Is miminally toxic
Rapid in onset
Delivers profound anesthesia
Duration of action is sufficient
Sterile
Completely reversible
Most patients experience minimal pain with the proper administration of topical anesthetic before injection of the local anesthetic.
In children, is it important to know how much the child weighs because the dentist must be careful not to exceed the maximum allowable dose, which is calculated as milligrams of the drug administered per kilogram, or pound, of body weight.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 9

10. Mechanism of Action
Local anesthesia temporarily blocks the normal generation and conduction action of the nerve impulses.
Local anesthesia is obtained by injecting the anesthetic agent near the nerve in the area intended for dental treatment.
Induction time is the length of time from the injection of the anesthetic solution to complete and effective conduction blockage.
The dentist will normally test for anesthesia before beginning the procedure by touching local and distant tissues that are normally nonresponsive with adequate anesthesia.
It is also important to help the patient differentiate pain from other unpleasant sensations such as vibration, pressure, and noise. None of these other problems can be resolved with the use of additional local anesthesia.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 10

11. Duration Time from induction to completion of the reversal process
Short-acting
Local anesthetic agent lasting 60 to 180 minutes
Intermediate
Local anesthetic agent lasting 120 to 240 minutes
Long-acting
Local anesthetic agent lasting 240 to 540 minutes
What is a dental procedure that might require a short-acting local anesthetic? What might require longer anesthesia?
Sometimes a procedure takes longer than anticipated; some people metabolize anesthesia faster than anticipated, so additional local anesthesia is administered.
Remember that local anesthetic also has a different duration of action on the pulp of the tooth versus the soft tissue of the oral mucosa.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 11

12. Vasoconstrictors Indications for use Types
Prolongs the duration of an anesthetic agent by decreasing the blood flow in the immediate area of the injection
Decreases bleeding in the area during surgical procedures
Types
Epinephrine
Levonordefrin
Neo-Cobefrin
During a surgical procedure, additional anesthetic may be injected directly into the surgical site, not because the patient is feeling pain but because additional hemostasis is required (to stop bleeding).
Because a vasoconstrictor prolongs the duration of action, this allows for the use of less anesthetic.
Epinephrine is one of the vasoconstrictors most commonly added to local anesthetics used in dentistry.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 12

13. Ratio of Anesthetic Solution to Vasoconstrictor
1:20,000
1:50,000
1:100,000
1:200,000
What ratio represents a higher concentration of vasoconstrictor mixed with local anesthetic? (1:20,000)
1: 20,000 means that there is 1 g (or 1000 mg) of solute (drug) contained in 20,000 mL of solution (0.05 mg/mL).
Why use a higher concentration of vasoconstrictor? (To prolong the effect of the local anesthesia and to decrease/control bleeding in the area.)
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 13

14. Contraindications to the Use of Vasoconstrictors
Unstable angina
Recent myocardial infarction
Recent coronary artery bypass surgery
Untreated or uncontrolled severe hypertension
Untreated or uncontrolled congestive heart failure
In addition to these contraindications for the use of a vasoconstrictor, numerous medications that a patient may be taking may necessitate limited or no usage of a vasoconstrictor.
There are situations in which an otherwise healthy patient presents for emergency treatment and because of the vital signs (increased blood pressure as a result of extreme pain and or lack of sleep) may require the use of less vasoconstrictor than normal.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 14

15. Injection Techniques
Infiltration is achieved by injecting the solution directly into the tissue at the site of the dental procedure.
Most frequently used to anesthetize the maxillary teeth
Used as a secondary injection to block gingival tissues surrounding the mandibular teeth.
Block anesthesia is achieved by injecting near a major nerve, with the entire area served by that nerve being numbed.
Type of injection required for most mandibular teeth
What is an important consideration with respect to the needle when you are loading the syringe with a cartridge?
A short needle is generally used for the administration of all types of local anesthesia in children.
Remember, when passing the loaded syringe to the dentist, keep it below the patient’s chin and away from the field of view. Keep the loaded syringe present throughout the procedure in the event that additional anesthesia is required.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 15

16. Fig. 37-3 Maxillary injections. A, Local infiltration. B, Field block
Fig Maxillary injections. A, Local infiltration. B, Field block. C, Nerve block. (From Malamed SF: Handbook of local anesthesia, ed 5, St Louis, 2004, Mosby.)
The upper middle photo demonstrates the proper positioning of the needle during a posterior superior alveolar nerve block, which is used to anesthetize the maxillary first, second, and third molars.
The bottom left photo highlights the approximate positioning of a lower right inferior alveolar nerve block of the mandible.
The bottom right photo demonstrates interproximal insertion of the needle, buccal to lingual, to deposit additional anesthetic after the completion of an incisive nerve block.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 16

17. Anesthetic Cartridge Precautions
Cartridges should be stored at room temperature and protected from direct sunlight.
Never use a cartridge that has been frozen.
Do not use a cartridge if it is cracked, chipped, or damaged in any way.
Never use a solution that is discolored or cloudy or has passed the expiration date.
Do not leave the syringe preloaded with the needle attached for an extended period.
Never save a cartridge for reuse.
Where should used or unused damaged anesthetic cartridges, as well as needles, be deposited? (In a sharps container that is disposed of properly.)
Always check expiration dates and, when restocking a treatment room, place the older cartridges in such a way that they will be used before the newer ones.
It is prudent to leave used local anesthetic cartridges on the treatment tray until the procedure has been completed so that an accurate account of the amount of anesthetic used is properly documented in the patient records.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 17

18. Fig. 37-10 Color-coding of local anesthetic cartridges
Fig Color-coding of local anesthetic cartridges. (From Malamed SF: Handbook of local anesthesia, ed 5, St Louis, 2004, Mosby.)
This chart outlines the color-coding system developed by the American Dental Association for the various types of local anesthesia with and without a vasoconstrictor. The chart corresponds to color bands on the cartridges.
Although the bands offer a tool for quick recognition, dental assistants should always double-check by reading the label as well.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 18

19. Local Anesthetic Cautions
Injection into a blood vessel
Infected area
Localized toxic reaction
Systemic toxic reaction
Temporary numbness
Paresthesia
How is injection of local anesthesia into a blood vessel prevented?
Why is infiltration of local anesthesia into an infected area not advised? ([1] Inadequate anesthesia resulting from the different pH of infected tissue and [2] the risk of spreading infection.)
What is paresthesia? (Loss of feeling—numbness that lasts beyond the expected duration of the local anesthetic.)
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 19

20. Electronic Anesthesia
A noninvasive method to block pain electronically with the use of a low-level current of electricity through contact pads that target a specific electronic waveform directly to the nerve bundle at the root of the tooth
Benefits to the patient
No needles
No postoperative numbness or swelling
Chemical-free
No risk of cross-contamination
Reduced fear and anxiety
Patient control over comfort level
What is a shortcoming of this alternative to conventional local anesthesia?
Local anesthesia is still the most widely used form of pain control in dentistry.
In addition to electronic anesthesia as an alternative to the generic syringe, some dentists use a local anesthetic pump that delivers the anesthetic at a predetermined rate in accordance with to multiple variables.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 20

21. Chapter 37 Lesson 37.2
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 21

22. Learning Objectives
Describe nitrous oxide/oxygen sedation and its use in dentistry.
Discuss the importance of reducing the dental team’s exposure to nitrous oxide.
Assist in the administration and monitoring of nitrous oxide/oxygen sedation.
(Cont’d)
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 22

23. Learning Objectives Discuss IV sedation and its use in dentistry.
(Cont’d)
Discuss IV sedation and its use in dentistry.
Discuss general anesthesia and its use in dentistry.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 23

24. Inhalation Sedation
Nitrous oxide/oxygen (N²O/O²) is a combination of gases inhaled by the to help eliminate fear and to aid relaxation.
History
The use of nitrous oxide dates back to 1844.
Dr. Horace Wells was the first to use nitrous oxide on patients.
Effects
N²O/O² is nonaddictive.
Onset is easy, side effects are minimal, and recovery is rapid.
N²O/O² produces stage I anesthesia.
N²O/O² dulls the perception of pain.
Why should local anesthesia always be used in conjunction with nitrous oxide?
Although nitrous oxide and oxygen are nonaddictive, dental professionals and members of the public may easily become addicted to the feeling they experience when they inhale this gas.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 24

25. Advantage of Using N²O/O²
Administration is simple and easily managed.
The services of an anesthetist or other special personnel are not required.
N²O/O² has an excellent safety record.
Side effects are minimal.
The patient is awake.
Recovery is rapid.
N²O/O² can be used with patients of all ages.
It is important for the patient to remain awake throughout administration to permit proper titration of the gases according to the patient’s signs and symptoms.
When administering nitrous oxide to a child, make sure to have children’s nasal masks available. Regardless of the patient’s age, a qualified dental team member should stay with the patient at all times.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 25

26. Contraindications to the Use of N²O/O²
Pregnancy: first trimester
Nasal obstruction: problems inhaling through the nose
Emphysema: increased O²
Multiple sclerosis: breathing difficulties
Emotional stability: altered perception of reality
What is an example of a common nasal obstruction? (Deviated septum.)
In some medical conditions the use of N²O/O² is actually desirable because of the additional oxygen being delivered.
The dental assistant should also be familiar with the unit because he or she may be required to deliver pure oxygen to a patient in an emergency.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 26

27. Inhalation Sedation Equipment
Cylinders: Gases are dispensed from steel cylinders, which are colored green for O² and blue for N²O.
N²O machines are portable or part of the dental unit.
Control valves control the flow of each gas.
A flowmeter indicates the rate of flow of the gases.
The two gases are combined in a reservoir bag, which the patient draws on for breathing.
(Cont’d)
If portable units are in place, the valves are not usually opened unless the unit is about to be used.
Before the use of nitrous oxide, both cylinders should be checked for adequate remaining gas levels.
All parts of the delivery system should be in acceptable working condition. The reservoir bag should be checked frequently for leaks.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 27

28. Inhalation Sedation Equipment
(Cont’d)
Gas hose
Carries the gases from the reservoir bag to the mask or nosepiece.
Masks: supplied in sizes for adults and children
The nosepiece through which the patient breathes the gases
Scavenger system
Protection from the occupational risks of N²O.
Be aware that a large amount of facial hair (especially a moustache) may interfere with an adequate seal of the nosepiece, decreasing the amount of the sedative delivered to the patient and perhaps increasing the amount of leakage to the surrounding environment and exposure to the dental team.
A scavenger system is essential for safely gathering and disposing of any unused or exhaled nitrous oxide outside the building.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 28

29. Fig. 37-15 Nitrous Oxide gas lines are color-coded.
What color represents nitrous oxide? (Blue.)
What color represents oxygen? (Green.)
The metal plate in the wall is an outlet for the nitrous oxide and oxygen supplies, as well as an outlet for the scavenging system to prevent nitrous oxide from accumulating.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 29

30. Exposure to Nitrous Oxide
Used only for patient treatment
Never administered for recreational purposes
How to reduce N²O hazards to dental personnel
Use a scavenger system.
Use a patient mask that fits well.
Discourage the patient from talking.
Vent gas outside the building.
Routinely inspect equipment and hoses for leaks.
Use a monitoring-badge system to detect N²O.
Why is it important to discuss with patients the steps in the administration of nitrous oxide, as well as what they may expect from the dental procedure itself, before beginning a procedure?
An office should have a schedule in place for routine inspection of nitrous oxide equipment for safety and maintenance.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 30

31. Fig Scavenger system attached to mask and evacuation unit to redirect unused nitrous oxide gas. (From Clark M and Brunick A: Handbook of nitrous oxide and oxygen sedation, ed 3, St Louis , 2008, Mosby.) (Courtesy of Accutron.)
This photo depicts the nasal mask that is placed over the patient’s nose to deliver nitrous oxide, in combination with the scavenging device that collects excess or exhaled nitrous.
It is important that the mask be placed with the corresponding end over the bridge of the nose for a proper fit.
The nosepiece is placed over the nose and the tubing is secured behind the headset of the dental chair.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 31

32. Patient Preparation for Inhalation Sedation
Review the patient’s health history.
Obtain baseline vital signs.
Describe the procedure of administering the gases.
Describe the use of the mask and the importance of nasal breathing.
Describe the sensations that the patient will experience.
Reassure the patient.
Should the baseline vitals be recorded? If so, where?
Discussing what the patients may or should expect, as well as addressing his orher questions or concerns, will help avoid or alleviate any unwarranted anxiety during the procedure.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 32

33. Assisting in the Administration of Inhalation Sedation
Start with pure oxygen while establishing the patient’s tidal volume.
Slowly titrate the nitrous oxide until the desired results are achieved.
The patient should refrain from talking or mouth-breathing.
The N²O/O² analgesia should end with the administration of 100% O² for 3 to 5 minutes.
Obtain postoperative vital signs and compare them with the preoperative recordings.
The tidal volume is the amount of air inhaled and exhaled with every breath.
Starting with pure oxygen will help patients get accustomed to having the nasal mask in place and practice breathing through their nose.
What does inhaling 100% oxygen at the end of the procedure help prevent? (Diffusion hypoxia.)
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 33

34. Antianxiety Agents
Sedatives are the drug of choice for physicians and dentists seeking to relieve anxiety in their patients.
Criteria for use
A patients is very nervous about a procedure.
A procedures is long or difficult.
The patient is mentally challenged.
The patient is a very young child requiring extensive treatment.
Antianxiety medications are used as an adjunct to dental treatment.
Patients with extreme dental fear may require this type of medication for the first few visits.
Anxiolytics are also sometimes prescribed to mentally challenged patients who may be uncooperative.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 34

35. Commonly Prescribed Sedatives
Secobarbital sodium (Seconal)
Chlordiazepoxide hydrochloride (Librium)
Diazepam (Valium)
Chloral hydrate (Noctec): for children
Diazepam is a benzodiazepine that is available in 2-, 5-, and 10-mg tablets; it may also be given intramuscularly, IV, or as an oral solution.
Secobarbital is a sedative-hypnotic barbiturate, chlordiazepoxide a benzodiazepine, and chloral hydrate a sedative-hypnotic, used more often in pediatric dentistry.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 35

36. IV Sedation
Antianxiety drugs administered IV throughout a procedure at a slower pace, providing a deeper stage I analgesia
(Cont’d)
Conscious IV sedation is frequently used by an oral surgeon during such procedures as the extraction of third molars, especially in difficult cases, such as when teeth are impacted and surgical removal of bone is necessary.
Local anesthesia is administered once the patient is stable with IV conscious sedation. This also helps ease postoperative pain until oral analgesics can be taken.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 36

37. IV Sedation Patient assessment
(Cont’d)
Patient assessment
A health history is taken, a physical examination performed, and signed consent obtained.
Baseline vital signs are taken and recorded.
Oximetry and electrocardiography are performed and recorded.
The patient’s weight is taken and recorded for the determination of dosage.
All medications administered IV are calculated according to the patient’s weight and are additionally titrated according to the vitals and feedback from the patient during the procedure.
What is oximetry?
A change in a patient’s blood oxygen percentage throughout surgery may indicate that one of the medications (e.g., a narcotic analgesic) administered IV is suppressing the respiratory drive.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 37

38. IV Sedation Patient monitoring
(Cont’d)
Patient monitoring
Physiologic measurements are recorded every 15 minutes:
Level of consciousness
Respiratory function
Oximetry
Blood pressure
Heart rate
Cardiac rhythm
In addition to the operating dentist and the assistant, a registered nurse is usually present to properly administer the medications through the IV line and monitor the patient’s vital signs throughout surgery.
Although vital signs may only be formally recorded every 15 minutes, some dental offices choose to record them more frequently.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 38

39. General Anesthesia
A controlled state of unconsciousness with a loss of protective reflexes—including the ability to maintain an airway independently and to respond appropriately to physical stimulation or verbal command—that produces stage III general anesthesia.
(Cont’d)
General anesthesia is indicated for severely medically compromised or mentally disabled individuals cannot be adequately treated in a regular dental setting.
Because of the loss of protective reflexes with general anesthesia, the patient is intubated, usually through the nose (to keep the oral cavity clear), for delivery of oxygen and anesthetic gases; other medications are administered simultaneously by way of an IV line.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 39

40. General Anesthesia Pharmacologic makeup Combination of gases N²O/O²
(Cont’d)
Pharmacologic makeup
Combination of gases
N²O/O²
Halothane or enflurane mixture
IV agents such as thiopental sodium and methohexital sodium
A thorough preoperative examination, including a physical examination, blood tests, and sometimes cardiac tests, is performed and reviewed as part of the medical history before the administration of general anesthesia.
Both inhalation gases and IV agents are calculated and chosen according to the patient’s health history, the anticipated length and type of surgery, and the anesthesiologist’s preferences.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 40

41. Four Stages of Anesthesia
Stage I: analgesia
At this stage the patient is relaxed and fully conscious.
The patient is able to keep his or her mouth open without assistance and is capable of following directions.
The patient has a sense of euphoria and a reduction in pain.
Vital signs are normal.
The patient can move into different levels of analgesia.
(Cont’d)
What is an example of a stage I anesthesthetic agent? (Nitrous oxide/oxygen.)
Monitoring of the level of consciousness is important to ensure that the titration of the anesthetic is desirable.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 41

42. Four Stages of Anesthesia
(Cont’d)
Stage II: excitement
At this stage the patient is less aware of his or her immediate surroundings.
The patient starts to become unconscious.
The patient may become excited and unmanageable.
Nausea and vomiting may occur.
This is an undesirable stage.
Patients undergoing IV conscious sedation should have their vital signs monitored carefully as they are put into a deeper stage I level of anesthesia.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 42

43. Four Stages of Anesthesia
(Cont’d)
Stage III: general anesthesia
This stage of anesthesia begins when the patient becomes calm after stage II.
The patient feels no pain or sensation.
The patient will become unconscious.
This stage of anesthesia can be met only under the guidance of an anesthesiologist in a controlled environment such as a hospital.
Although the patient is thought to feel no pain, local anesthesia is usually administered to control bleeding throughout the procedure, as well as at or near the end to help with postoperative pain control.
A throat pack is always placed so that the airway and esophagus are protected from instruments, irrigating solutions and blood, materials, and free tissue debris, as well as to keep the stomach from filling with liquid that may cause postoperative nausea and vomiting.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 43

44. Four Stages of Anesthesia
(Cont’d)
Stage IV: respiratory failure or cardiac arrest
At this stage the lungs and heart slow down or stop functioning.
If this stage is not reversed quickly, the patient will die.
Because of the risk, it is very important that patients be well-informed, that they thorough discuss the dental office’s consent form, and that all other anesthetic options have been exhausted or found to be inappropriate before general anesthesia is chosen.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 44

45. General Anesthesia Patient preparation Preoperative instructions
(Cont’d)
Patient preparation
Preoperative physical examination
Laboratory tests
Signature of patient or legal guardian on a consent form
Preoperative instructions
The dentist will review the procedure, as well as the risks.
The patient must not have anything to drink or eat 8 to 12 hours before undergoing general anesthesia.
“NPO” stands for a Latin abbreviation meaning “nothing by mouth.”
Depending on the seriousmess of the dental surgery and the outcome, most patients will be treated as day surgery patients; others will have to remain in the hospital, monitored in a controlled environment for a prescribed amount of time after surgery.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 45

46. Recordkeeping for Sedation Methods
Always document the following measures and observations:
Review of the patient’s medical history
Preoperative and postoperative vital signs
Patient’s tidal volume if inhalation sedation is being used
Times at which anesthesia began and ended
Peak concentration administered
Postoperative time (in minutes) required for patient recovery
Adverse events and patient complaints
Along with a detailed account of the actual surgical procedure, the name, concentration, and amount of anesthesia used; the time at which it was administered; and the route of administration (e.g., local infiltration, IV, inhalation, etc.) should be noted.
For local anesthesia, remember to note whether it contained a vasoconstrictor and. if so, the type and concentration.
Any postoperative instructions should also be documented.
Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved. 46