consciousness. It is important that dental surgeons working with children have a very
clear idea of the clinical status of sedated patients. These are:
(1) the patient's eyes are open;
(2) the patient is able to respond verbally to questions;
(3) the patient is able to independently maintain an open mouth (this may preclude the
use of a mouth-prop);
(4) the patient is able to independently maintain a patent airway;
(5) the ability to swallow;
(6) the child is a normal pink colour.
All these criteria are evidence of conscious sedation. For this reason it is important
not to let a child go to sleep in the dental chair while receiving treatment with
sedation as closed eyes may be a sign of sleep, over-sedation, loss of consciousness,
or cardiovascular collapse.
4.9.2 Pulse oximetry
Pulse oximetry is a non-invasive method of measuring arterial oxygen saturation
using a sensor probe placed on the patient's finger or ear lobe, which has a red light
source to detect the relative difference in the absorption of light between saturated and
desaturated haemoglobin during arterial pulsation. The probe is sensitive to patient
movement, relative hypothermia, ambient light, and abnormal haemoglobinaemias, so
false readings can occur. In room air, a child's normal oxygen saturation (SaO 2 ) is
97% to 100%. Adequate oxygenation of the tissues occurs above 95% while oxygen
saturations lower than this are considered hypoxaemic.
Key Points
Monitoring a sedated child involves:
- alert clinical monitoring⎯skin colour, response to stimulus, ability to keep mouth
open, ability to both swallow and to maintain an independent airway, normal radial
pulse; - the use of a pulse oximeter (except for nitrous oxide inhalation sedation).
4.10 ORAL SEDATION
4.10.0 Introduction
The onset of the effect of oral sedatives is variable and is largely dependent on the
individual's rate of absorption from the gastro-intestinal tract, which can be affected
by the rate of gastric clearance, the amount of food in the stomach, and even the time
of the day. In addition, the dosage is determined by the body weight. Therefore, a set
of properly calibrated bathroom scales is needed to enable the correct dose of sedative
to be estimated for each patient. Despite this, some children may spit out the drug,
leaving the clinician uncertain about the exact dosage that was administered. To
combat this, some sedationists administer the liquid sedative using a syringe placed in
the buccal mucosa or mix the drug with a flavoured elixir. The patient may require up
to an hour of supervised postoperative recovery.
4.10.1 Oral sedatives