Week 2 - Anesthesia

What are the methods of pain control used in dentistry to alleviate or reduce anxiety and pain? (7) **exam

1. topical anesthesia

2. local anesthesia

3. inhalation sedation

4. antianxiety agents

5. intravenous (IV) sedation

6. general anesthesia

7. mind-body medicine

What are the levels of pain control? (5)

1. Analgesia: is the absence of a normal sense of pain. (tylenol)

2. Anesthesia: is complete loss of feeling or sensation without loss of consciousness (lydocaine)

3. Paresthesia: is the loss of sensation (pins and needles or nerve damage temporary or long term)

4. sedation: is the state of being clam (meds to help calm or sleep)

5. conscious sedation: is a depressed level of consciousness with the ability to maintain a patient’s airway (inhalation, oral, or intravenous)

How is local anesthesia obtained? How does it work?

Local anesthesia is obtained by injecting the anesthetic agent near the nerve in the area intended for dental treatment

Local anesthesia temporarily blocks the ability of the nerve membrane to generate an impulse.

• Once the injection is given the anesthetic diffuses (spreads) into the nerve and blocks its normal action causing the patient to feel numb in the area.

What is induction time?

the length of time from the injection of the anesthetic solution to complete and effective conduction blockage

What is the duration of local anesthesia?

Length of time from induction until reversal process is complete

• action of anesthetic reverses as the bloodstream carries away the anesthetic solution

What are the two chemical groups (chemical composition) for anesthesia?

Amides: a majority of the dental local anesthetic drugs fall under this category ex: (lidocaine, mepivacaine, bupivacaine, prilocaine, and articaine) and are metabolized in the liver.

Esters: primarily used as topical anesthetics and are metabolized primarily in the plasma.

What does each local anesthetic cartridge contain? **exam

Local anesthetic drug-choice depends on procedure, health of patient and dentist’s preference.

• it has sodium chloride (salt) and distilled water

Induction vs duration?

Induction: length of time from injection to complete and effective blockage

Duration: length of time from induction until the reversal process is complete

What are the different durations for local anesthetic?

Short-acting local: lasts 30 min

Intermediate-acting: can last approx 60 min(1-2 hours)

Long-acting: approx 90 min

What are guidelines for handling anesthetic cartridges? (6)

1. Cartridges should be stored at room temperature and protected from direct sunlight

2. Never use a cartridge that has been frozen

3. Do not use a cartridge if it is cracked, chipped, or damaged in any way

4. Never use a solution that is discolored or cloudy or has passed the expiration date

5. Do not leave the syringe preloaded with the needle attached for an extended period

6. Never save a cartridge for reuse

What is a vasoconstrictor in anesthesia? Example?

An agent in the local anesthetic that slows down the uptake of an anesthetic agent into the bloodstream.

• this increases the duration of action

Epinephrine is one type of vasoconstrictor added to local anesthetic solution

When are vasoconstrictors are used? (5)

1. Blood vessels to the site of administration are constricted.

2. Absorption into the cardiovascular system is slowed.

3. Local anesthetic toxicity is minimized.

4. Effect of the anesthetic is prolonged by decreasing blood flow to the area of injection.

5. Bleeding at injection site is decreased.

How much vasoconstrictor is added to the local anesthetic solution? What does each ratio mean?

A small quantity of vasoconstrictor is added to the local anesthetic solution in a ratio of vasoconstrictor to anesthetic solution.

• This means that there is one part (drop) of epinephrine per 100,000 parts (drops) of anesthetic solution.

The smaller the ratio, the higher the percentage of vasoconstrictor. Most times it is best to use as high a ratio as possible

Which cartridge contains the most epinephrine? ** exam question like this

1:200,000

1:100,000

1:50, 000

1:50,000

• smaller amount means more present

What are contraindications to vasoconstrictors? (2)

Vasoconstrictors should not be used on patients with a history of heart disease.

• Angina (heart related chest pain)

• Heart attack

• Coronary artery bypass surgery,

• Hypertension (high blood pressure)

• Congestive heart failure

The vasoconstrictor may also interfere or interact with other drugs the patient is taking.

Changes to the patient’s medical history or medication intake are critical for the dental team to be aware of.

What anesthetic to use for patients that can’t have vasoconstrictors?

Using an anesthetic that is free from epinephrine (plain anesthetic) for these patients

• can’t plain for everyone since it doesn’t have a profound effect

• Because a vasoconstrictor may cause strain on the heart, the use of an anesthetic solution without a vasoconstrictor is recommended for patients with cardiovascular disease

What are complications and precautions of local anesthetics? (5)

1. injecting into a blood vessel

2. infection

3. localized and toxic reactions

4. temporary numbness

5. paresthesia

What is injecting into a blood vessel? Infection?

Injecting into a blood vessel

• Can alter function of vital organs, notably the heart. Dentist will aspirate before injecting any local anesthetic.

Infection

• The effects of a local anesthetic agent may be delayed or even prevented if injected into an area of infection, such as an abscess. The infection inhibits the anesthetic solution from penetrating to the nerves.

What is localized and toxic reactions?

Localized reactions –contact dermatitis –inflammation of the tissues caused by an allergic reaction.

Systemic reactions – affecting the central nervous system or the cardiovascular system

What is temporary numbness?

This temporary numbness disappears as the effect of the anesthetic agent wears off. The numb area can feel swollen or tingly when it is not. “Lip feels fat”

What is paresthesia? What is caused by? **exam

When numbness lasts after the effects of local anesthetic solutions have worn off.

Can be caused by:

• injury to the nerve sheath during injection or surgery.

• Bleeding into or around the nerve sheath.

• Use of contaminated anesthetic solution.

• Paresthesia can be temporary or permanent. Most cases are resolved in about 8 weeks

What are post op instructions? **exam

1. avoid hot and cold foods

2. chew on other side of mouth

3. avoid biting cheek or tongue

   1. be careful of this, depends if maxillary or mandibular

4. topical anesthetics will last 15 min

5. local anesthetic will last 2-4 hours

What is electronic anesthesia? Benefits? (6)

Blocks pain electronically with the use of a low current of electricity

Benefits:

• No needles

• No post op numbness or swelling

• Chemical free

• No cross-contamination risk

• Reduced fear and anxiety in patients

• Patient control over own comfort level

What are dental sedation methods?

1. inhalation sedation (N2O)

2. antianxiety agents

3. intravenous sedation (IV)

4. general anesthesia (GA)

5. mind-body medicine

What is inhalation sedation? purpose? characteristics? how is it given?

Nitrous Oxide/oxygen (N2O/O2)

• combination of gases inhaled to help eliminate fear and to aid relaxation

• It is colorless, tasteless and may have a sweet odor.

• The patient inhales the gas through a nosepiece feeling the effect almost immediately.

• The gas enters the blood stream through the lungs and travels quickly to the brain.

What are the effects of inhalation sedation? (4)

1. non-addictive

2. onset is easy, side effects are minimal, and recovery is rapid

3. produces stage 1 anesthesia/analgesia

4. creates feeling of relaxation and calmness

What to assess and monitor regarding patient before administrating nitrous oxide/oxygen? (2)

1. review patient’s medical history prior to administering nitrous oxide

2. vital signs including blood pressure, pulse, and respirations should be recorded before, during, and after administration of N2O/O2

What are medical considerations for N2O/O2 use? (8)

1. Certain medical conditions or chronic disorders make N2O/O2 Use a contraindication

2. Chronic pulmonary disorders (COPD, asthma, lung diseases)

3. Upper respiratory infections

4. Cardiac diseases can increase artery pressure.

5. First trimester of pregnancy

6. Psychiatric disorders and drug-related dependencies: can cause hallucinations.

7. Middle ear disturbance/surgery: can lead to increased gas volume and pressure.

8. Critically ill patients: can lead to a B12 deficiency and produce anemia

what are advantages of N2O/O2 use? (8)

1. Administration is simple and easily managed by the dentist

2. The services of an anesthesiologists or other specialized personnel are not required

3. Excellent safety record

4. Adverse side effects are minimal

5. Produces a pleasant, relaxing experience for the patient.

6. The patient is awake and can communicate and follow directions

7. Recovery is rapid and complete within minutes.

8. Can be used with patients of all ages

what are disadvantages of N2O/O2 use? (2)

1. Some patients may experience nausea or vertigo.

2. Patients who have behavioral problems may react in a negative way and act out those behavior issues.

What are safe work practices for N2O/O2 use? (5)

1. Scavenger System

   1. Reduces the nitrous oxide released into the treatment room.

2. Venting Exhaust Fumes Outside

   1. Exposure overtime has proven adverse health effects. Exhaust fumes should be vented outside away from fresh-air intake vent.

3. Properly Fitting Mask

   1. Should be properly fitted for each patient. Check the reservoir bag using oxygen to ensure the bag is not overinflating or under inflating while patient is breathing.

4. Limit Talking

   1. Advise the patient to limit talking during administration of N2O. To breathe through their nose and avoid breathing through their mouth.

5. Exposure Assessment

   1. Can be assessed for exposure by wearing dosimeter badges or placing an infrared spectrophotometer in the room.

What are the patient education instructions for nitrous oxide?

Patient is informed about what to expect:

• How the gas is administered.

• Proper use of the mask –importance of breathing through their nose.

• Sensations of warmth and tingling that the patient will experience.

• Refrain from talking or mouth breathing.

• While receiving the nitrous oxide they will remain conscious, aware and in control of their actions.

What are antianxiety agents used for? How?

Administered for the relief of anxiety.

Prescribed to induce a varying level of sedation (minimal to moderate) and also for deep sedation or general anesthesia.

Can be administered orally, intravenously or by inhalation.

• Patient is asked to take the drug orally 30 to 60 minutes before the appointment.

• Patient will be drowsy and should not drive themselves to their appointment

What is criteria for using antianxiety agents? (4)

A patient is very nervous about a procedure

A procedure is long or difficult

The patient is mentally challenged

The patient is a very young child requiring extensive treatment

Who does intravenous sedation? Process? what does it result in?

The process of starting, monitoring and removing IV sedation is completed only by an individual who is trained and certified in this area.

• Prior to administration a physical exam and a pertinent history and a signed consent are obtained.

• Baseline vitals are taken, blood oxygen concentration and electrocardiogram (ECG) are completed and recorded.

• Patient’s weight recorded for dose determination.

IV conscious sedation results in a minimally depressed level of consciousness. (might not remember)

• Patient maintains an open airway, and respond appropriately to verbal or physical stimulation

where is the IV line placed? what to look for as DA during this process? what to do in case of emergency?

IV lines are placed in a large vein on the top of the hand or lower arm.

The IV line should be continuously monitored to make sure that there is not inflammation of the vein or pain at the insertion site or that the needle has not become dislodged and leaking fluid under the skin, has not clotted or cracked.

• Physiologic measurements should be recorded at least every 15 min.

Supplemental oxygen and a defibrillator must be available for immediate use in case of emergency

What does general anesthesia result in?

A controlled state of unconsciousness with a loss of protective reflexes.

• Unable to maintain an airway independently

• Unable to respond appropriately to physical stimulation or verbal command.

• Provides a controlled state of loss of consciousness.

• Produces Stage III anesthesia

What are the four stages of anesthesia? **exam

Specific or a combination of pain control agent scan produce different levels of consciousness or unconsciousness,

Stage I

• Patient is relaxed and fully conscious. The patient experiences a sense of euphoria and reduction in pain. Patient can keep their mouth open and follow directions. Vital signs are normal.

Stage II

• Excitement stage. Patient is less aware of surroundings and may lose consciousness. Patient may become excited and unmanageable, nausea or vomiting may occur. Undesirable stage.

Stage III

• General anesthesia. The patient feels no pain or sensation. Patient becomes unconscious. Can be achieved only under the guidance of an anesthesiologist in a controlled environment.

Stage IV

• Respiratory failure or cardiac arrest. If not quickly reversed, it can result in death

How to prepare patient for GA? What to educate them on? (6)

Pre-operative physical exam and/or laboratory tests

Consent form must be signed by patient or legal guardian.

Review the possible risks and reactions to the general anesthesia.

Patient must not eat or drink for 8 to 12 hours prior to receiving general anesthesia.

Patient must have a driver home.

Patient should not be left alone while recovering.

What to document for anesthesia and pain control?

Always document the following measures and observations:

1. Review of the patient’s medical history

2. Pre-operative and postoperative vital signs

3. Vitals are also documented every 15 min in the patient chart during IV, general and oral sedation

4. Type of anesthesia used.

5. Patient’s tidal volume if inhalation sedation is being used.

6. Times anesthesia began and ended.

7. Peak concentration administered.

8. Post-operative time (in minutes) for patient recovery.

9. Adverse events and patient complaints.

10. Recorded in the progress section of the patient’s chart.

What is mind-body medicine? Common techniques? (7)

Methods of reducing anxiety and pain through different non-pharmacologic techniques

Some common techniques include:

1. Distraction (e.g., listening to music, watching iPad)

2. Relaxation techniques

3. Guided techniques

4. Deep breathing

5. Biofeedback

6. Hypnosis

7. Acupuncture