Key points

Introduction

Dentists who provide sedation or anesthesia to adolescent dental patients are urged to have current knowledge of pharmacology. They must recognize indications and contraindications to the delivery of sedation and anesthesia medications, including epinephrine-containing local 
anesthetics. Management of pain, anxiety, and behavior should be the goals of sedation/anesthesia. All decisions must be made considering risk versus benefit.

Dentists are obligated to use safe prescribing practices. The goal of this article is to aid the dental provider in managing pain and anxiety and in modifying behavior to safely complete dental procedures in adolescent patients.

Definitions

There have been many definitions of sedation in dentistry used over the years. Clinical standards for sedation in dentistry parallel the guidelines established by the American Society of Anesthesiology (ASA) for anesthesiologists. ^, The American Academy of Pediatric Dentistry (AAPD) and the Academy of Pediatrics (AAP) maintain guidelines for sedation of the pediatric patient, defined as any patient under the age of 21. The American Dental Association (ADA) also has guidelines for the use and teaching of sedation and anesthesia in dentistry.

The following definitions for levels of sedation are excerpted from the AAPD, AAP, and ADA guidelines.

Spectrum of anesthesia and sedation

Arthur Guedel, MD introduced the concept of anesthetic signs and stages. His early work studied diethyl ether for general anesthesia. He observed 4 distinct stages as patients were administered increasing quantities of inhaled ether. The stages represent a continuum or spectrum from which no sedation becomes general anesthesia. ^,

In stage 1 or the analgesia phase, consciousness is not lost. Stage 2 is the excitatory phase. Between stages 2 and 3, consciousness is lost. Stage 3 is defined as the surgical anesthesia stage. Dentists who are not formally trained in deep sedation and general anesthesia should limit their practice to stage 1, the analgesia phase.

Guedel’s classification still has value. It has been modified and adapted for new drugs and techniques. Dentists must understand that as agents are administered, they produce an effect along a “ spectrum of pain and anxiety control. ” Dosage and route determine the level of sedation or anesthesia.

Fig. 1 shows the spectrum. At the far left, there is no sedation or anesthesia. To the right, there are levels of conscious sedation up to the vertical bar. The red bar represents loss of consciousness. To the right of the red bar is deep sedation/general anesthesia. The experienced provider may not need a graphic representation to determine level of sedation or anesthesia; however, a classification system is necessary. The dentist must understand where he or she is on the spectrum and its relationship to where they want to be. Success in the minimal-moderate range is dependent on adequate pain control with local anesthesia. Increasing depth of sedation increases risk and requires additional formal training.

Levels (Spectrum) of Sedation/Anesthesia.

Preoperative evaluation

Dental treatment can affect both the physical and the psychological “well-being” of adolescent patients. Before treatment (with or without sedation), patients should have a complete physical examination and psychological assessment to evaluate risk. This assessment allows the provider to determine need.

Medical, dental, and psychological histories guide the dentist in choosing a treatment modality. The evaluation should include a medical history questionnaire, physical examination, and a discussion with the patient, parent, and/or caregiver. For the adolescent patient, extra time and attention should be spent on understanding the reason for their behavior (fear, anxiety, developmental disability). With the information collected, the dentist can establish a physical status classification and determine risk factors. Medical consults can be obtained as needed.

A preoperative consult/evaluation with a physician is not medical clearance. The purpose is to evaluate and make recommendations. Preoperative goals include medical optimization using strategies to reduce risk and improve outcome. ^,

Physical status classification

The ASA has a physical classification system for estimating medical risk for patients receiving general anesthesia for surgical procedures. The system was adopted in the early 1960s and has remained virtually unchanged. Currently, it is used to evaluate risk associated with procedures regardless of anesthetic technique. ^,

• The ASA Physical Status Classification System :

  • Class 1: A healthy patient (no physiologic, physical or psychological abnormalities)

  • Class 2: A patient with mild systemic disease without limitation of daily activities (ie, controlled asthma; controlled hypertension)

  • Class 3: A patient with severe systemic disease that limits activity but is not incapacitating (ie, uncontrolled hypertension: uncontrolled diabetes)

  • Class 4: A patient with incapacitating systemic disease that is a constant threat to life

  • Class 5: A moribund patient not expected to survive without the operation

  • Class 6: A brain-dead patient whose organs are being removed for donor purposes

∗If the procedure to be performed is an emergency, an “E” is added to the above classification system (eg, ASA PS 2E). In the outpatient medical and dental settings, classes 5 and 6 have been eliminated.

Adolescent patients who are ASA PS class 1 or 2 are appropriate candidates for minimal, moderate, or deep sedation in the dental office. Individual consideration is recommended for patients in ASA PS classes 3 and 4. ^, Dentists are encouraged to consult with appropriate subspecialties for patients at increased risk for adverse events because of their underlying conditions. Remember, the ultimate responsibility and liability rest with the dentist who decides to treat or not treat.

Sedation

Sedation of adolescent patients for the delivery of oral health care uniquely is challenging. A sedation plan should maximize benefit and minimize associated risks for adverse outcomes. Each sedation patient requires individual consideration. Patient extremes in responsiveness and acceptance will vary depending on a host of factors.

Once pharmacosedation is planned, the dentist must consider which agents to use and how to administer. The choice will depend on the desired level of sedation. Developmental and chronologic ages are important considerations. Younger patients and severely developmentally disabled patients may require deeper levels of sedation to gain control of their behavior as compared with more cooperative patients.

The following routes are available for delivery of drugs to adolescent patients:

• 1.

  Oral/rectal

• 2.

  Sublingual

• 3.

  Topical

• 4.

  Intranasal

• 5.

  Inhalational

• 6.

  Subcutaneous

• 7.

  Intramuscular (IM)

• 8.

  Intravenous (IV)

• 9.

  Interarterial

• 10.

  Intrathecal (in spinal fluid)

• 11.

  Transdermal (through epidermis)

Techniques (oral, rectal, sublingual) that administer agents that are absorbed through the gastrointestinal (GI) tract or oral mucosa are termed enteral sedation. Parenteral techniques (IM, IV, intranasal, submucosal, subcutaneous, intraosseous) bypass the gastrointestinal tract and enter directly into the systemic circulation. Oral (mostly) and rectal routes are subject to the enterohepatic circulation and first-pass effect before the drug is released to the systemic circulation. This significantly reduces the amount that is bioavailable and should be considered when choosing an agent and dose.

The most popular route used for dental sedation is the oral route. Advantages over the parenteral routes include acceptance by patients, low cost, ease of administration, decreased incidence of adverse reactions, and no equipment needed for delivery. However, oral sedation does have some significant disadvantages, such as reliance on patient compliance, a prolonged latent period, erratic and incomplete absorption from the GI tract, inability to titrate, inability to lighten or deepen sedation as needed, and a prolonged duration of action. With oral sedation, “stacking” or adding additional agents after the initial dose is discouraged.

Drugs administered topically are readily absorbed from nonkeratinized tissue. Topical applications in dentistry are usually local anesthetics. They are highly effective at relieving pain associated with intraoral injections.

Intranasal administration has become increasingly popular in pediatric dentistry. It is easily administered to resistant, uncooperative, or precooperative patients. ^, Although there is brief discomfort with administration, direct absorption into the systemic circulation makes the drug rapidly bioavailable. Compared with oral sedation, there is reduced time to onset and total time spent in the office. Midazolam, a water-soluble benzodiazepine, is a commonly used drug via this route. ^, The mucosal atomization device is the preferred method for administration.

Inhalational administration occurs when gaseous agents pass from the respiratory apparatus (nose/mouth, trachea, and lungs) into the cardiovascular system. There are a variety of agents available for inhalational sedation and anesthesia. In dentistry, nitrous oxide/oxygen (N ₂ O/O ₂ ) sedation is the main drug used for inhalation sedation. ^, It is easily titrated to effect, with minimal side effects or complications. A disadvantage of nitrous oxide is that it is not a potent anesthetic, so there may be failure. Also, a delivery system is required with a fail-safe and scavenging system. The equipment must be calibrated annually, and there needs to be adequate office ventilation to prevent chronic exposure to those administering the sedation. Other more potent inhalation agents include sevoflurane, isoflurane, and desflurane. They are used in the maintenance of general anesthesia. Sevoflurane is also indicated for mask induction of general anesthesia.

Subcutaneous injection is administration of a drug beneath the skin into the subcutaneous tissue. Rate of absorption is directly proportional to the vasculature in the area of injection. Slow rates of absorption limit its usefulness in dentistry.

The IM route administers the drug directly into the muscle. This parenteral technique allows for quick onset with rapid maximal clinical effect. The disadvantages include prolonged deep sedation, injury to tissues at the site of injection, and overdose. IM administration is often unpredictable, and there is no mechanism for titration to effect. Ketamine, a dissociative anesthetic, is the most commonly used drug via the IM route and is often used for sedation and induction of the uncooperative patient.

Intravascular drug administration represents the most effective, predictable method of delivery for adequate sedation of most patients. Advantages include rapid onset with short duration of latency and a shortened recovery period. However, complications at the site of venipuncture and risk for overdose are disadvantages. Many drugs given intravenously do not have reversal agents; therefore, the dentist must be prepared to manage deeper sedation and other complications, such as allergic reactions, which may not be seen with other less effective modes of delivery.

A variety of drugs are available for sedation and anesthesia of the adolescent patient. These drugs primarily include inhalation sedation/anesthesia, benzodiazepines, sedative hypnotics, antihistamines, alpha agonists, and analgesics. Table 1 lists available drugs for sedation.

The sedation/anesthetic regimen for adolescent dental patients should carry a high therapeutic index with a wide safety margin and a low probability for abuse. It should be modified based on the adolescent’s physical, developmental, mental, sensory, behavioral, cognitive, and emotional needs. Selection of the fewest agents paired with the procedural goals results in safe practice. Painful procedures require analgesics; diagnostic procedures use sedatives, and anxious patients benefit from benzodiazepines. Combinations of different classes of medications are often used. However, when 3 or more agents are administered simultaneously, the potential for an adverse outcome increases. ^{, ,}

Agents available for sedation of adolescent patients