The effect of electronic dental analgesia during sonic scaling.

The aim of the present study was to investigate the effects of electronic dental analgesia (EDA) during sonic scaling. The clinical trial included 30 healthy adult subjects and was conducted as a randomised single-blind split-mouth design. The applied procedure consisted of periodontal scaling by means of a sonic scaler, while using the EDA device either in an active or placebo state. Rather similar results were obtained for the subjective pain rating in both the active and the placebo trials. When patients rated their discomfort on a scale 0-4 from no pain to very severe pain, the mean (s.d.) score for both the EDA and the placebo was 1.2 (0.6). The subjective pain estimate was positively correlated to the electrical current intensity provided. This implied that with a stronger pain experience, patients tried to administer more anaesthesia by turning the dial of the control box to an increased intensity of the electrical current. This remained insufficient to eliminate pain sensation. It was concluded that application of electronic dental anaesthesia in periodontal treatment remains questionable.

Performance of the Baxter disposable patient-controlled analgesia infusor under hyperbaric conditions.

Hyperbaric oxygen treatment may require the concurrent administration of drugs. A study was performed to assess the suitability of the infusor device from the Baxter Patient-Controlled Analgesia system, for drug delivery during hyperbaric therapy. Thirty infusor devices were used to deliver 5% dextrose, 50% dextrose or propofol solutions under conditions 1 and 2.3 atmospheres of pressure. The increased pressure caused an increase in flow of 4.27%, 1.79% and 9.84% for 5% dextrose, propofol and 50% dextrose respectively.

Patient-controlled sedation using midazolam.

Midazolam was given for sedation as an initial bolus, followed by either a continuous infusion or a patient controlled infusion during third molar extractions. The results showed that there were no significant changes in blood pressure, pulse rate or oxygen saturation during the procedure. Both methods gave good amnesia to events at the start, (100%), as well as to events during, (70% and 75%), and at the end, (61% and 70%), of surgery. There was high acceptance of both methods of sedation (93% and 98% respectively). There was no patient preference for either method of sedation, nor was the operator able to distinguish between the two methods. Hence it is concluded that patient controlled infusion and continuous infusion of midazolam are both satisfactory methods of sedation for patients undergoing surgery under local anaesthesia.

Patient-controlled drug administration during local anesthesia: a comparison of midazolam, propofol, and alfentanil.

STUDY OBJECTIVE: To evaluate the perioperative effects of alfentanil, midazolam, and propofol when administered using a patient-controlled analgesia (PCA) device during local anesthesia. DESIGN: Randomized, single-blind comparative study. SETTING: Outpatient surgery center at a university teaching hospital. PATIENTS: Ninety outpatients undergoing minor elective surgical procedures with local anesthetic infiltration were assigned to one of three treatment groups. INTERVENTIONS: After premedication with midazolam 1 mg intravenously (IV) and fentanyl 50 micrograms IV, patients were allowed to self-administer 2 ml bolus doses of either alfentanil 250 micrograms/ml, midazolam 0.4 mg/ml, or propofol 10 mg/ml at minimal intervals of 3 minutes to supplement a basal infusion rate of 5 ml/hr. MEASUREMENTS AND MAIN RESULTS: The total intraoperative dosages of alfentanil, midazolam, and propofol were 2.7 +/- 1.1 mg, 4.7 +/- 2.7 mg, and 114 +/- 42 mg, respectively, for procedures lasting 48 +/- 28 minutes to 51 +/- 19 minutes (means +/- SD). Propofol produced more pain on injection (39% vs. 4% and 6% in the alfentanil and midazolam groups, respectively). Episodes of arterial oxygen saturation less than 90% were more frequent with alfentanil (28%) than with midazolam (3%) or propofol (13%). Using the visual analog scale, patients reported comparable levels of discomfort, anxiety, and sedation during the operation in all three treatment groups. Postoperative picture recall was significantly decreased with midazolam versus alfentanil and propofol. Finally, postoperative nausea was reported more frequently in the alfentanil group (29%) than in the midazolam (10%) or propofol (18%) groups, contributing to a significant prolongation of the discharge time in the alfentanil-treated patients. CONCLUSIONS: When self-administered as adjuvants during local anesthesia using a PCA delivery system, alfentanil, midazolam, and propofol were equally acceptable to patients. However, propofol and midazolam were associated with fewer perioperative complications than was alfentanil.

Patient-controlled analgesia. A serious incident.

A patient received a massive overdose of papaveretum intravenously (estimated to be 180 mg) when the glass syringe of a patient-controlled analgesia machine disengaged from the drive mechanism. She was successfully resuscitated. The pump, on loan from the supplier, had passed a brief evaluation by the infusion pump test house designated by the Medical Devices Directorate of the Department of Health; it has since been withdrawn. It is recommended that patient-controlled analgesia equipment should be placed at or below patient heart level. The Department of Health is called on to institute a full, independent evaluation scheme for patient-controlled analgesia equipment.