Anesthesia

Key points

Choice of anesthesia should be defined by what is best for the patient
Staff members must be properly trained in resuscitation procedures and available equipment
Intravenous sedation, depending on the drug, may lead to conscious sedation or general anesthesia
General anesthesia: Loss of consciousness, patients not arousable, even by painful stimulation
For elected procedures, general anesthesia should be considered with care
During conscious sedation, verbal contact with patient is maintained

General Considerations

The choice of anesthesia depends on many variables including the complexity of treatment, duration of treatment, need for patient awareness and the response during treatment, only to name a few. In general, the clinician and patient should discuss the risks and benefits of possible anesthesia and sedation types and select the type that provides the minimum adequate amount of anesthesia and sedation needed to complete the treatment procedure. Guidelines regarding the patient's medical condition regarding anesthesia should be followed carefully.

The two main types of anesthesia/sedation include infiltration with local anesthetics and regional anesthesia with local anesthetics. Either type of anesthesia can be combined with conscious sedation. In cases of complex surgery, general anesthesia may be considered and the patient should be referred to a highly trained specialist who is experienced in the use of general anesthesia.

Infiltration with local anesthetic

Mostly lidocaine, articaine or mepivacaine with or without a vasoconstrictor in a carpule that is deliverd though syringe injection
Bevel of needle should be parallel with periosteum
Slow injection of anesthetic warmed to body temperature
Topical anesthesia should be used prior to injection
Duration of anesthesia varies with patient metabolism and anxiety

Regional anesthesia with local anesthetic

Inferior alveolar block anesthesia for pain control in distal mandibular areas
In frontal areas of non-resorbed jaws where there is less corticalized bone local infiltration is often sufficient
A more technique-sensitive process than local inflitration
Aspiration is mandatory since 5% of aspirations are positive and need reorientation of needle and reaspiration or else new injection with reaspiration
Facial nerve may be temporarily paralyzed

Conscious sedation

Usually combined with local anesthesia
The patient remains conscious and can respond appropriately to verbal commands
Nitrous oxide and oxygen administered through the nose. Nitrous oxide has sedative and analgesic effects
Intravenous (IV) delivery of benzodiazepines is a safe and widely-used method for obtaining conscious sedation
There are contraindications to conscious sedation such as pregnancy, allergy and alcohol intoxication. Therefore, a thorough medical history is important
Resuscitation equipment, a positive-pressure oxygen delivery system and an intubation tube should always be available during conscious sedation
National regulations regarding administration of conscious sedation should be followed

Fig 2: Nitrous oxide and oxygen administered through the nose. Nitrous oxide has sedative and analgesic effects.Courtesy of Dr. Daniel van Steenberghe, Brussels

General anesthesia

In general anesthesia there is a complete loss of consciousness, amnesia, analgesia, relaxation of skeletal muscles and loss of control of the autonomic nervous system
Therefore, general anesthesia should only be provided in hospitals or equipped medical centers and where essential postoperative facilities under medical surveillance are available
The use of preoperative clonidine or benzodiazepines reduces the dose of anesthetics needed
Physiologic monitoring and airway management are mandatory
Duration of anesthesia is normally not an issue