The comparison of the effect of lorazpam and chlordiazpoxide as premedication on prevention of recall perioperative events after general anesthesia

Background: Premedication is used for preparing patients before operation in order to induce
sedation, homodynamic stability, analgesia, and prevention of nausea and vomiting. The side effects
of the drugs and amnesia also need consideration. The purpose of this study was to compare the
effect of Lorazpam and Chlordiazpoxide as premedication in prevention of recall perioperative
events, following general anesthesia.
Materials and Methods: This clinical trial was carried out during October 1997 to March 1999 on
128 adult patients who had inclusion criteria and were randomly assigned to two groups. The
patients in group 1 each received 2mg lorazpam and in group 2 each received 10mg
chlordiazpoxide at night before operation and again at the morning of operation. Twenty-four
hours after operation, all patients were asked about perioperative events and then scores of
amnesia were specified for all patients of the two groups. The data were analyzed by U-Mann
Whitney and chi-square tests.
Results: The patients ranged between 20 to 50 years of age. The mean age in group 1 (Lorazpam)
and group 2 (chlordiazpoxide) were 38 ± 3.9 and 39.3 ± 2.8, respectively (P>0.05). The results
showed that Lorazpam group recalled perioperative events were less than those of chlordiazpoxide
group (P<0.05).
Conclusion: It was found that induced amnesia with Lorazpam was significantly more than that of
chlordiazpoxide, suggesting that Lorazpam may be preferable as a premedication before operation.