Drug Overdose – Sedatives and Anxiolytic Agents

The number of dental procedures for pediatric dental patients requiring the use of sedative and/or anxiolytic agents has increased in the past several decades. Associated with the increase in pharmaceutical management of pediatric dental patients is an increased likelihood of untoward medical emergencies. In recognition of this situation the American Academy of Pediatrics and the American Academy of Pediatric Dentistry published guidelines for the monitoring and management of sedated pediatric patients during and after treatment. However even with the practitioner following these guidelines there is a low but occurring rate of potential life threatening events, such as apnea, airway obstruction, laryngospasm, pulmonary aspiration, desaturation and others.

The sedation of children is different from the sedation of adults. Physiologic functions in children may vary considerably from those in adults. The metabolic rate is increased in pediatric patients. Conversely enzyme systems responsible for the biotransformation of specific drugs may not be as functional as in adults. This can lead to the increased possibility of higher blood levels of the sedative drugs even when the calculated dosage is reduced from the adult dose based on reduced weight. In addition, the effectiveness of particular dosage o administered sedative/anxiolytic agents may vary from patient to patient. AAPD.

Factors determining drug dosages in children include:

  • Age and weight of the child: In general, the older the child, the larger the dosage to achieve the desired clinical result. However in very young, precooperative children larger dosages may be needed to overcome their extreme level of fear.
  • Mental attitude: The greater the degree of anxiety the larger the dose of drugs required.
  • Level and length of time of sedation desired. The depth of sedation (minimal, moderate, deep) and the anticipated length of time for treatment will influence the required dosage. The depth of sedation will be dictated by the complexity of treatment. A minimally invasive restoration may be completed with less cooperation than an aesthetic full coverage restoration requiring pulp therapy.
  • Physical activity of the child: Hyperactive tend to require increased drug dosages.
  • Stomach contents: The presence of food in the stomach influences the rate of absorption of orally administered drugs. Patient receiving sedative/anxiolytic drugs whether enterally or parenterally should be NPO so as not to affect the absorption rate and of importance to reduce the likelihood of vomiting and possible airway obstruction and aspiration.
  • Ability to titrate: The ability to titrate aids in the determination of the proper drug dosage for a patient. Intravenous and inhalation administration allows titration, while oral, intramuscular, and submucosal administration does not permit titration.

It is beyond the scope of this course to detail the preoperative preparation (medical, social and dental history), required monitoring equipment and personnel, and training of operator and support staff. Studies have shown it is common for children to pass from the intended level of sedation to a deeper unintended level of sedation. Those practitioners engaged in administering sedative/anxiolytic drugs should have the skills to rescue a patient from a deeper level than intended for the procedure. For example, if the intended level is minimal, the practitioner should have the skills to rescue from moderate level. If the intended level is moderate, the practitioner should have the skill to rescue from deep level. If the intended level is deep level the practitioner should have the skill to rescue from general anesthesia. These skills are learned from comprehensive instruction that includes 12-24 hours of didactic and hands on training. In addition, practitioners engaged in sedation/ anxiolytic drug administration should be certified in Advanced Cardiac Life support (ACLS) and/or Pediatric Advanced Life Support (PALS) AAPD.

Oral sedation is the most popular route of administration by pediatric dentists,11 although alternative routes such as the intranasal, sublingual and buccal routes are becoming increasingly popular. Among the oral sedative drugs most commonly administered, benzodiazepines (midazolam, diazepam) and narcotics (meperidine) are the only drugs with reversal agents and are preferred over drugs nonreversibility i.e.: chloral hydrate, hydroxyzine and promethazine. Therefore our discussion will be limited to benzodiazepines and narcotics.

It is important to note the use of local anesthetics in concurrence with sedative/anxiolytic agents can increase respiratory depression in patients and therefore the amount of local anesthesia administered to the sedated patient should closely monitored and kept well below the maximum recommended dose.