S H Kestenberg’s research while affiliated with Newton-Wellesley Hospital and other places

Numerous potential problems have been associated with long term or occupational exposure to both nitrous oxide and halothane. Despite the lack of firmly established cause-and-effect relationships, particularly in humans, it would seem prudent to use techniques that minimize operator exposure. With this in mind, a scavenging system for use in both conscious sedation and general anesthetic techniques was developed which fulfills the requirements of both general dentists as well as those administering general anesthesia. This paper describes this system and its adaptation to the commonly used Magill circuit. It also briefly reviews the factors involved in potential toxicity caused by long term exposure to nitrous oxide and halothane.

Flumazenil is an imidazobenzodiazepine that binds specifically to the central benzodiazepine receptor and antagonizes the actions of diazepam and other benzodiazepines. Previous studies in Europe have shown flumazenil at doses of 2 to 30 mg IV to reverse sedation in patients sedated with flunitrazepam, midazolam, and diazepam when evaluated by subjective criteria. The purpose of this study was to determine if flumazenil at 0.015 mg/kg IV was efficacious in shortening the recovery time of young, healthy dental patients sedated with diazepam (0.15 mg/kg IV) and restoring their psychomotor function to presedation levels. A total of 21 patients were randomized to placebo or flumazenil, sedated with diazepam, underwent a restorative dental procedure, and were then administered the test drug. Evaluations of psychomotor function by the Trieger test, Digit-Symbol Substitution test, Romberg test, and nurse questioning were carried out before sedation and at 10-minute intervals after test drug. Observations by the patients and nurses were not significantly different before versus after test drug. The investigator, however, found that flumazenil resulted in more rapid awakening. Patients treated with placebo exhibited significantly greater deficits in the number of dots missed and sum of deviations on the Trieger test than flumazenil-treated patients. Similar time-related deficits were recorded for the Digit-Symbol Substitution test. Flumazenil, at a dose of 0.015 mg/kg, was found to be efficacious in reducing the recovery time after diazepam sedation in dental patients.