Sedation Using Intranasal Dexmedetomidine in Upper Gastrointestinal Endoscopy
Status:
Completed
Trial end date:
2010-04-01
Target enrollment:
Participant gender:
Summary
Upper gastrointestinal endoscopy, like many other diagnostic and therapeutic procedures, may
be associated with discomfort. Although upper endoscopy is usually of shorter duration and
better tolerated by patients, most trials investigating the influence of analgesia and
sedation have been performed on patients undergoing this procedure. Some patients may
tolerate colonoscopy without sedation, but various techniques are used to limit discomfort
and pain. Selection and dosing of sedatives depends on the patient's emotional state, the
intensity of pain during examination, foreseeable technical difficulties, the endoscopist's
experience, the presence or absence of anesthesia personnel, and hospital-specific
procedures.
Conscious sedation is a popular technique for colonoscopy and upper gastrointestinal
endoscopy. The combination of an opioid and a benzodiazepine is known to provide good
analgesic and sedative conditions during endoscopy. This combination of opioid and
benzodiazepine, however, also increases the risk of respiratory depression. Therefore,
pharmacologic agents which may provide adequate sedation without respiratory depression are
of great interest to clinicians.
Dexmedetomidine is a highly selective α2-adrenoceptor agonist with sedative and analgesic
effects. Compared with clonidine, it is more selective for the α 2 adrenoceptor and acts as a
full agonist in most pharmacologic test models. Potentially desirable properties include
decreased requirements for other anesthetics and analgesics, a diminished sympathetic
response to stress and the potential for cardioprotective effects against myocardial
ischemia. When compared with conventional sedatives such as opioids or benzodiazepines, its
lack of respiration depression is a distinct advantage. Previous studies using
dexmedetomidine for sedation has been promising with maintenance of respiratory function.
Patients are readily arousable. With intravenous slow bolus administration, there is a
minimal increase in blood pressure initially, followed by a slight decrease in blood
pressure. Lower dose ranges, avoidance of rapid bolus injection, and a slow rate of
administration tend to decrease these circulatory side effects. Many clinical studies have
shown that it can be well and safely used intravenously, intramuscularly and transdermally.
Although not an officially technique, there are also reports of intranasal administration
resulting in fairly predictable onset in both adults and children.