Comparison of Two Intravenous Drug Combinations for Ambulatory Oral & Maxillofacial Surgery

The purpose of this pilot study was to compare two commonly employed intravenous drug combinations; I) nitrous oxide, midazolam, fentanyl, and ketamine and II) the same combination with substitution of propofol for ketamine, for use during wisdom teeth extraction. Measures of recovery, amnesia testing 20 minutes after induction and after completion of recovery tests, patient satisfaction, and surgeon satisfaction will be evaluated. The data from this pilot study will be used to obtain preliminary estimates of effect sizes and to select primary and secondary endpoints for the design of a larger scale and more definitive trial of the two anesthetic approaches.

The widespread application of various ambulatory anesthetic techniques has paralleled the rapid rise of ambulatory surgery. It has been estimated that over half of all elective surgery is performed in an ambulatory setting. In addition, well over 3,000,000 intravenous sedations are administered in dental offices annually where local anesthesia is obtainable to control intraoperative pain. These intravenous sedation techniques have historically been an integral part of pain and anxiety control in the dental setting and have now gained widespread application in all of ambulatory surgery. A number of intravenous anesthetic techniques have been developed to achieve sedation levels ranging from conscious sedation where patients respond purposefully to verbal commands to deep sedation where patients cannot be easily aroused and protective reflexes may be altered. The goal of all of these techniques is to create a comfortable environment for the patient and a cooperative patient for the surgeon. Ideal technique should pose minimal physiologic challenge to the patient while providing amnesia for the procedure. Most of the intravenous sedation techniques in widespread use include a combination of drugs. These combinations function in an additive if not synergistic way. The pharmacological properties of their constituents achieve this ideal. The most frequently used drug when used alone and the most common to the various combinations is midazolam, a benzodiazepine. Midazolam has been shown to provide safe sedation with reliable anterograde amnesia. The duration of these effects is dose dependent. A short acting narcotic, usually fentanyl, is often times included to increase sedation levels and to add a modicum of analgesia. Other short acting agents can also be included to deepen the sedation level. These agents are usually added in incremental doses as the surgical setting requires. Both propofol and ketamine can induce general anesthesia but in significantly smaller doses provide additional sedation. These two agents come from different drug classes. Proponents of each cite advantages and disadvantages. Nitrous oxide is also commonly used in the dental setting.