During the last two years, the well-known positive role of benzodiazepines
(midazolam and diazepam) in conscious sedation, both in adults and pediatric
patients, has been confirmed by several studies. However, problems concerning
the role of sedation and analgesia in nonoperative endoscopy are still a matter
of debate.
Particular attention has focused on attempts to identify the “ideal
candidate” for conscious sedation, and on the importance of providing
patients with information before the procedure, which should be matched to
each patient's style of coping. Before detailed information about a medical
procedure is given blindly, the clinician should investigate whether such
information will benefit or adversely affect the patient receiving it.
An important aspect of the sedation procedure is the prevention of hypoxia
and cardiopulmonary complications. Recent endoscopic experience has provided
little additional information concerning the well-known risk of
oxygen desaturation during conscious sedation. Performing endoscopy in sedated
patients reduces, but does not eliminate, the risk of hypoxia. Some independent
variables capable of predicting severe desaturation have been recognized,
such as basal SaO2 < 95 %,
respiratory disease, more than one attempt needed for intubation, emergency
procedure, and an American Society of Anesthesiologists score of III or IV.
As far as preparation is concerned, some light has been cast by a meta-analysis
of available studies concerning the role of sodium phosphate and polyethylene
glycol electrolyte lavage solution (PEG-ELS). The former preparation has been
found to be as effective and less costly compared with the latter. In particular,
sodium phosphate may be preferable in patients without cardiovascular or renal
co-morbidity, and in those with a tendency to develop nausea or bloating.
