2. General Anesthesia
Dr. William Morton, a Massachusetts dentist, was
looking for a way to painlessly extract teeth.
There was no local or general anesthesia available to
make removing teeth tolerable.
Although Dr. Morton knew about nitrous oxide
from his association with another dentist, Dr.
Horace Wells, he wanted a more powerful agent. He
discussed the problem with Dr. Charles T.
Jackson, a physician and scientist who suggested
that he try ether.
3. General Anesthesia
Anxiety and pain can be modified by both
psychological and pharmacological techniques.
In some instances, psychological approaches are
sufficient. However, in many
instances, pharmacological approaches are required.
4. Local and General
Anesthesia
Local anesthetics are used to control regional pain.
Sedative drugs and techniques may control fear and
anxiety, but do not by themselves fully control pain
and, thus, are commonly used in conjunction with
local anesthetics.
General anesthesia provides complete relief from
both anxiety and pain.
5. General Anesthesia
The use of sedation and general anesthesia in
dentistry is safe and effective when properly
administered by trained individuals.
General anesthesia (GA) is when you are totally
unconscious. In this state, you can't feel any
pain, even without local anesthesia.
6. General Anesthesia
In General anesthesia patient can't reliably breathe
on his own, so for more complex procedures (such
as fillings - these are actually more complex than
extractions under GA!) and procedures of longer
duration you need to having a "breathing tube"
inserted.
7. Minimizing the Risk
Dentists who are qualified to utilize sedation and general
anesthesia have a responsibility to minimize risk to patients
undergoing dental treatment by:
Using only those drugs and techniques in which they have
been appropriately trained;
Limiting use of these modalities to patients who require
them;
Conducting a preoperative evaluation of each patient
consisting of at least a thorough review of medical and
dental history, a focused clinical examination and
consultation, when indicated, with appropriate medical and
dental personnel;
8. Minimizing the Risk
Conducting physiologic and visual monitoring of the
patient;
Having available appropriate emergency drugs, equipment
and facilities and maintaining competency in their use;
Maintaining fully documented records of drugs
used, dosage, vital signs monitored, adverse
reactions, recovery from the anesthetic, and, if
applicable, emergency procedures employed;
Utilizing sufficient support personnel who are properly
trained for the functions they are assigned to perform;
Treating high-risk patients in a setting equipped to provide
for their care.
9. Minimizing the Risk
Throughout the IV Sedation procedure, patient`s pulse and
oxygen levels are measured using a "pulse oximeter".
This gadget clips onto a finger or an earlobe and measures
pulse and oxygen saturation.
It gives a useful early warning sign if you're getting
dangerously low on oxygen
unresponsiveness
slow breathing.
Blood pressure before and after the IV Sedation procedure
should be checked
10. IV Sedation
In contrast, what is usually called "IV sedation” in
dentistry is conscious sedation.
Conscious sedation is a minimally depressed level
of consciousness during which the patient is able to
breathe independently and/or respond purposely
to verbal command.
11. IV Sedation
When a drug, usually of
the anti-anxiety
variety, is administered
into the blood system
during dental
treatment, this is
referred to as
Intravenous Conscious
Sedation.
Conscious sedation is
sometimes (incorrectly)
referred to as "twilight
sleep" or "sleep
dentistry".
12. IV Sedation
The drugs which are usually used for IV sedation
are not painkillers (although some pain-killing
drugs are occasionally added), but anti-anxiety
drugs.
While they relax you and make patient forget what
happens, he will still need to be numbed
13. IV Sedation: Drugs used
Anti-anxiety sedatives ("benzos"): Midazolam and
Diazepam
For procedures up to about 1 1/2 hours
IV administered benzos have 3 main effects: they
reduce anxiety/relax patient, they make him
sleepy, and they produce partial or total. Total
amnesia is more common with midazolam compared
to diazepam
The Venflon is the reversal agent for benzos
(Flumazenil)
14. IV Sedation: Drugs used
Barbiturates(sleep-inducing drugs)
For procedures more than 2 hours
The only barbiturate which is still occasionally used is
called Pentobarbital Sodium (tradename: Nembutal).
In the absence of a trained
anesthesiologist, barbiturates are pretty dangerous to
use, for a number of reasons: it's very easy to have the
patient slip into general anaesthesia by mistake, where
breathing and heart rate are dangerously lowered and
coma and death can follow. And there's no reversal
agent.
15. IV Sedation: Drugs used
Opioids
can be used as an add-on to either benzos (for
procedures up to about 1 1/2 hours) or barbiturates (for
procedures longer than 2 hours).
Opioids are always used in the so-called Jorgensen
technique (which in its basic form involves
pentobarbital, an opioid, and an anticholinergic)
sometimes used in the US for procedures taking 2 hours
or more.
16. IV Sedation: Drugs used
Opioids
can be used as an add-on to either benzos (for
procedures up to about 1 1/2 hours) or barbiturates (for
procedures longer than 2 hours).
Opioids are always used in the so-called Jorgensen
technique (which in its basic form involves
pentobarbital, an opioid, and an anticholinergic)
sometimes used in the US for procedures taking 2 hours
or more.
17. IV Sedation: Drugs used
Opioids
Opioids which may be used for IV sedation include:
Meperidine (Demerol)
Morphine
Butorphanol (Stadol)
Nalbuphine (Nubain)
Fentanyl (Sublimaze)
Pentazocine (Talwin)
18. IV Sedation: Drugs used
Propofol
Some anaesthetists use Propofol instead of benzos.
The advantage of this is the very rapid recovery
time, less than 5 mins.
The disadvantage is the drug must be continuously
administered, so the drug is pumped in using an
electric infusion pump, the dose rate is set by the
anaesthetist.
19. IV Sedation: Caution and
Contraindication
IV sedation is EXTREMELY safe when carried out
under the supervision of a specially-trained dentist.
Purely statistically speaking, it's even safer than
local anaesthetic on its own!
20. IV Sedation: Caution and
Contraindication
However,
contraindications include pregnancy, known allergy
to benzos, alcohol intoxication, CNS depression, and
some instances of glaucoma.
Cautions include psychosis, impaired lung or kidney
or liver function, and advanced age. Heart disease is
generally not a contraindication.
21. Oral Sedation
Most commonly, oral sedation (usually in the form
of anti-anxiety or "happy pills") is prescribed for
relieving anxiety in the hours immediately before a
dental appointment.
An anti-anxiety or sedative-hypnotic drug taken the
night before the appointment, an hour before going
to bed, can help with falling asleep and getting
some rest.
22. Oral Sedation
Anti-Anxiety Pills (Benzodiazepines or "Benzos")
In dentistry, the most commonly prescribed drugs for (or rather
against =)) anxiety belong to the "benzodiazepine" family. You've
probably heard of them by their tradenames - for
example, Valium, Halcion, Xanax, or Ativan.
Benzos directly and efficiently decrease anxiety by binding with
receptors in the brain which tone down activity in those parts of
the brain responsible for fear.
Benzodiazepines come in two flavours:
Sedative-Hypnotics: drugs which induce a calming effect, including
drowsiness ("sedation"). In higher doses, they induce a state
resembling physiological sleep ("hypnosis").
Anti-Anxiety Drugs: drugs which act primarily to relieve anxiety and
make you feel calm.
23. Oral Sedation
Anti-Anxiety Pills (Benzodiazepines or "Benzos”)
While all benzodiazepines act as sedatives AND
anti-anxiety drugs, some are more targeted at brain
areas which control sleep and wakefulness, while
others are more specifically targeted at brain areas
which control emotions such as fear.
24. Oral Sedation
Anti-Anxiety Pills (Benzodiazepines or "Benzos”)
The classification of whether a benzodiazepine is
sedative-hypnotic or anti-anxiety is to some extent an
arbitrary one, as the boundaries are quite fluid. As a
rule of thumb, in higher doses benzos act like
sedatives and may promote sleep, while in lower
doses, they simply reduce anxiety without sedation.
25. Oral Sedation
To do?
List Benzodiazepines according to their sedative or
Anti-Anxiety effects
26. Oral Sedation
Non-benzodiazepine hypnotic anti-anxiety drugs -
Ambien and Sonata
Ambien (that's the tradename for zolpidem tartrate) is
a strong sedative with only mild anxiety-reducing
properties.
Usual dose: 10 mg one hour before bedtime.
27. Oral Sedation
"Sleeping pills" (Barbiturates)
Only the short-acting barbiturates, pentobarbital
sodium (tradename: Nembutal) and secobarbital
sodium (tradename: Seconal) are occasionally used in
dentistry. The average recommended dose for adults
is 100 mg one hour before the scheduled appointment
for Nembutal, and 100-200 mg one hour before the
appointment for Seconal.
28. Oral Sedation
Antihistamines - Atarax and Phenergan
While antihistamines are primarily used to manage
allergies, several of them have an interesting side
effect: sedation! Some antihistamines, including
Atarax and Phenergan, have a strong calming and
sleep-inducing effect, and are marketed primarily as
sedative-hypnotics. They also help to prevent nausea
and being sick.
29. Oral Sedation
Antihistamines - Atarax and Phenergan
While antihistamines are primarily used to manage
allergies, several of them have an interesting side
effect: sedation! Some antihistamines, including
Atarax and Phenergan, have a strong calming and
sleep-inducing effect, and are marketed primarily as
sedative-hypnotics. They also help to prevent nausea
and being sick.
31. Nitrous Oxide
Nitrous oxide gas, often referred to as laughing gas
or sweet air, is an effective anesthetic drug that has
many benefits for patients seeking dental treatment.
The benefits of nitrous oxide are many, and the risks
are few. The gas is administered with a comfortable
mask placed over the nose, and the patient is
instructed to breathe in through the nose and out
through their mouth.
32. Nitrous Oxide
Nitrous oxide gas, often referred to as laughing gas
or sweet air, is an effective anesthetic drug that has
many benefits for patients seeking dental treatment.
The benefits of nitrous oxide are many, and the risks
are few. The gas is administered with a comfortable
mask placed over the nose, and the patient is
instructed to breathe in through the nose and out
through their mouth.
33. Nitrous Oxide
As a precaution, patients should not eat anything
for about two hours prior to use of the gas. The
patient begins to feel a pleasant level of sedation
anywhere from 30 seconds to three or four minutes.
The cheeks and gums will also begin to feel numb in
about a third of the patients.
34. Nitrous Oxide
After the gas is adjusted to the appropriate dose and
the patient is relaxed and sedated, the dentist can
comfortably give the injection (if needed) to the
patient, and then proceed with dental treatment.
35. Nitrous Oxide
After the treatment is completed, the patient is
given pure oxygen to breathe for about five
minutes, and all the effects of sedation are usually
reversed. Unlike IV sedation or general
anesthesia, the patient can almost always leave the
office by themselves, without an escort.
36. Nitrous Oxide
Nitrous oxide has few side effects.
High doses can cause nausea in some patients, and
about 10 percent of patients do not benefit from it.
Patients that are claustrophobic or have blocked
nasal passages cannot use nitrous oxide effectively.
37. Nitrous Oxide
Nitrous oxide has few side effects.
Nitrous oxide is one of the safest anesthetics
available. Interestingly, it is also routinely used by
anesthesiologists for general anesthesia in
combination with other more potent gases.
38. Nitrous Oxide
Dentists find nitrous oxide especially useful for
fearful patients as well as young children.
The effect of nitrous oxide is often remarkable. A
patient that was anxious just a minute or two before
treatment will become relaxed and calm.
Because nitrous oxide is so effective, dentists rarely
need to prescribe Valium for anxious patients before
treatment.
39. Nitrous oxide
Technique of Nitrous Oxide/Oxygen
Administration
Nitrous oxide/oxygen must be administered only by
appropriately licensed individuals, or under the direct
supervision thereof, according to state law.
The practitioner responsible for the treatment of the
patient and/or the administration of
analgesic/anxiolytic agents must be trained in the use
of such agents and techniques and appropriate
emergency response.
40. Nitrous oxide
Selection of an appropriately-sized nasal hood should
be made.
A flow rate of 5 to 6 liters/minute generally is
acceptable to most patients.
The flow rate can be adjusted after observation of the
reservoir bag.
41. Nitrous oxide
The bag should pulsate gently with each breath and
should not be either over- or underinflated.
Introduction of 100% oxygen for 1 to 2 minutes
followed by titration of nitrous oxide in 10% intervals
is recommended. During nitrous oxide/oxygen
analgesia/anxiolysis, the concentration of nitrous
oxide should not routinely exceed 50%.
42. Nitrous oxide
Nitrous oxide concentration may be decreased
during easier procedures (e.g., restorations) and
increased during more stimulating ones
(e.g., extraction, injection of local anesthetic). During
treatment, it is important to continue the visual
monitoring of the patient's respiratory rate and level
of consciousness. The effects of nitrous oxide largely
are dependent on psychological reassurance.
43. Nitrous oxide
Therefore, it is important to continue traditional
behavior guidance techniques during treatment.
Once the nitrous oxide flow is terminated, 100%
oxygen should be delivered for 3 to 5 minutes. The
patient must return to pre-treatment responsiveness
before discharge.
44. Nitrous Oxide:
Contraindications
Contraindications for use of nitrous oxide/oxygen
inhalation may include:
Some chronic obstructive pulmonary diseases
Severe emotional disturbances or drug-related
dependencies
First trimester of pregnancy
Treatment with bleomycin sulfate
45. Nitrous Oxide: Potential
harm
For some patients the feeling of "losing control" with nitrous
oxide may be troubling, and claustrophobic patients may find
the nasal hood confining and unpleasant.
Side effects of nitrous oxide include
nausea, vomiting, headache, and disorientation.
Lack of potency of nitrous oxide/oxygen inhalation
Interference of the nasal hood with injection to anterior
maxillary region
Nitrous oxide pollution and potential occupational exposure
health hazards