Dentaltown January 2020 - 79

the medication's actions in the patient's body. Any decrease in systemic proteins results in a
greater availability of free drug in the patient's system to exert its actions. Therefore, patient
conditions-typically associated with poor nutritional status, advanced age, or hepatic or renal
insufficiency-result in an increase in the free and active form of benzodiazepines. The lack
of proteins for binding is an indication for dosage reductions in these special populations.9

Absorption: Oral, intramuscular and intravenous
After oral administration, benzodiazepines are usually well absorbed by the gastrointestinal
tract. Although this is the case, they take longer to exert their intended effects, and their
time to onset may be challenging to coordinate with schedules and dental treatments.
Intravenous administration allows a quick distribution to the brain and by the way to
the central nervous system. Unlike other benzodiazepines, midazolam and lorazepam are
rapidly absorbed intramuscularly; therefore, the intramuscular route remains an alternative
for premedication in dentistry when the oral administration is impossible.10 This route also
presents issues in timeliness of absorption and the timing of dental treatment.
With the exception of triazolam, most benzodiazepines can be administered intravenously.
This may be the most controllable route of administration of all the possible routes of
benzodiazepine administration.

Benzodiazepines and patient selection
A discussion of sedation in dentistry warrants a brief conversation about appropriate
patient selection. Patient selection is key in the continuum of sedation.
Patient history, assessment and interview are key components in the appropriate selection
of a benzodiazepine for dental sedation. Standard patient history forms and patient interview
are familiar to practitioners, and permit dentists to assess a patient's American Society of
Anesthesiology (ASA) classification (see Table 1). Studies and assessment tools, like the
indicator of sedation needs (IOSN), demonstrate that oral and intravenous sedation may be
appropriate sedation techniques for patients who fall under the ASA I and II classifications.11
The IOSN provides objective scoring to allow for an appropriate sedation technique
(See Table 2, p. 80). It uses information about patient anxiety, medical and behavioral
status, and treatment complexity. Scores for each of these indicators range from 1-4 and
final scores sum to 3-12. A score of 3 or 4 indicates minimal need for sedation; 5 or 6,
moderate need; 7-9, high need; and 10-12 suggests very high need or even use of general

Table 1: American Society of Anesthesiologists Physical Status Classification
ASA I

Normal healthy patients.

ASA II

Patient with mild systemic disease.

ASA III

Patient with severe systemic disease.

ASA IV

Patient with severe systemic disease that is a constant threat to life.

ASA V

Moribund patient who is not expected to survive without the operation.

ASA VI

Patient declared brain-dead whose organs are being removed for donor purposes.
dentaltown.com \\ JANUARY 2020

http://www.dentaltown.com

Dentaltown January 2020

Table of Contents for the Digital Edition of Dentaltown January 2020