Patient‐controlled premedication by iv midazolam for ambulatory surgery

Abstract

Applying the principle and equipment of patient-controlled analgesia, this double-blind randomised study was designed to determine the premedication dose of midazolam and to provide information about the need for preoperative anxiety control. The effects of patient-controlled premedication by i.v. midazolam were compared to those of a 1-hour i.v. infusion of a fixed dose of 4 mg. Two groups of 25 patients were studied prior to ambulatory surgery. Using a visual analogue scale graded from 0 (no anxiety) to 100, anxiety and short-term memory as well as vital signs, vigilance, cognition and orientation were assessed before premedication and then every 20 min until admission to the operating room. In both groups, 40% of the patients were free of anxiety before premedication. Sixty-four percent of patients in the self-pre-medicated group never used the pump. The dose of midazolam was only 0.7 0.2 mg (mean SD) in this group taken as a whole, 0.7, 1.1 mg (mean SD) in the 8 patients who had an anxiety score at least equal to 50 before premedication, and 1.7 0.3 mg (mean SD) in the 9 patients who chose to push the button of the patient-controlled device. Anxiety and short-term memory scores decreased significantly and similarly in the self-premedicated group and in the fixed-dose group. For similar intraoperative anaesthetic requirements, time from the end of anaesthesia for determining whether a patient was ready for admission to the postrecovery lounge was shorter in the self-premedicated group (26 +/- 8 min vs 32 +/- 8 min; mean +/- SD. Reduced doses of midazolam self-administered via a patient-controlled device can result in a relaxed preoperative period and amnesia in ambulatory surgery patients. However, the level of anxiety before premedication was low, which calls into question the legitimacy of the patient-controlled premedication in this kind of population. The expense of the pump was not justified by the small number of patients using it, probably because they were worried by the technical nature and the invasiveness of this technique.

Patient anxiety and modern elective surgery: a literature review

“…Bernard et al. (1996) and Murdoch & Kenny (1999) both investigated patient‐controlled premedication.…”

“…(1996) and Murdoch & Kenny (1999) both investigated patient‐controlled premedication. Bernard et al. (1996) randomly assigned two groups of patients to receive either a fixed dose of midazolam 4 mg or a patient‐controlled pump containing midazolam.…”

Implant Treatment for the Patients with Severe Deep Bite Using Screwed Denture: Technical Note

“…These procedures are often associated with fear of pain, preoperative anxiety, and treatment-related mental stress. Anxiety caused by surgical procedures varies from a suppressed fear of pain to dental phobia which may make treatment impossible [10][11][12][13]. Midazolam has excellent anxiolytic qualities and is a well-established premedication agent.…”

“…It has depressant effects on the central nervous system with rapid effect and few adverse events [10,11,13]. Consequently, intravenous sedation with midazolam is advantage that the patients falls asleep and are completely unaware of the procedure being performed [11,12]. In addition, bite taking performed under an intravenous sedation is easier than that performed under general anesthesia.…”

Recent advances in patient-controlled sedation

“…Rodrigo et al [38] demonstrated in a crossover propofol/remifentanil PCS/PMS study in patients undergoing tooth extraction that both modalities were successful but that the majority of patients preferred PMS. PCS may result in a total dose of sedative that is lower [39] or higher [40] than operatorcontrolled sedation. Subjective preoperative measures such as anxiety level, desire for control, and expectations for comfort will be important and the PCS/PMS approach is not universally applicable.…”