Abstract
Background and Study Aims: As sedation with a combination of benzodiazepines and opioids has been associated
with an increased risk of serious cardiorespiratory events, it is rarely used in upper
gastrointestinal endoscopy. The combination is, however, still commonly used in sedation
for colonoscopy and endoscopic retrograde cholangiopancreatography (ERCP). This study
aimed to determine the benefits and disadvantages of adding pethidine to diazepam
(Diazemuls) in the sedation for colonoscopic examinations.
Patients and Methods: Seventy-one consecutive patients attending for routine colonoscopy were randomized
in a double-blind, placebo-controlled manner to sedation with Diazemuls alone or Diazemuls
with pethidine. The colonoscopist was at liberty to administrate any dose of Diazemuls
considered appropriate for the patient's age and size, following which the patient
was given an injection of pethidine 50 mg or a placebo. Both the patient and the endoscopist
were blind to whether pethidine or a placebo was used. Adequacy of sedation was assessed
and oxygen saturation recorded throughout the procedure. Oxygen was administered if
the oxygen saturation fell below 92 %. Patient satisfaction with sedation and recall
of the procedure was recorded, by questionnaire, one day after examination.
Results: A total of 71 patients were entered into the trial. The two groups were similar with
respect to age, sex, weight, alcohol intake, and state of health. An average of 18 mg
of Diazemuls was given in the pethidine group and 19 mg in the placebo group. There
was no statistically significant difference in the level of sedation obtained with
the two regimens, although there was a tendency for the combination of Diazemuls with
pethidine to give deeper sedation. Three patients were inadequately sedated with Diazemuls
alone, requiring the code to be broken for pethidine to be given. Nine colonoscopies
had to be abandoned due to patient intolerance in the group receiving Diazemuls, compared
to five in the group receiving the combination regime (p = 0.22). Twice as many patients
receiving the combination of Diazemuls with pethidine required oxygen supplementation
to maintain oxygen saturation during the procedure. This difference was highly statistically
significant (p = 0.008). With the administration of supplemental oxygen, the average
drop in oxygenation was similar in both groups. Satisfaction with sedation and recall
for the procedure were similar in both groups.
Conclusions: Although the patients had no preference for either regime, there may be an advantage
in using the combination of Diazemuls and pethidine, as there was a trend for this
combination to be preferred by the colonoscopists. The combination of a benzodiazepine
with an opiate should be used with caution, however, as there was a greater requirement
for oxygen in the group sedated by Diazemuls and pethidine.
