Vibration Analgesia in Propofol Infusion During Anesthesia Induction (VAPI)

In this study, the investigators seek to evaluate the role of vibration in the reduction of discomfort associated with painful stimulus associated with anesthesia induction. Through this study, the investigators hope to develop a comprehensive and cost-effective approach to minimize patient discomfort during anesthesia induction.

Background and Significance Infusion of propofol during the process of inducing anesthesia can cause a fair amount of transient discomfort to patients while the are on the operating table and of intact faculties. It is not uncommon for patients to cry out in pain. The investigators have noticed this first hand on numerous occasions and have wondered if there is a risk-free way to lesson the pain associated with propofol infusion. This study will focus on the use of vibration analgesia to potentially reduce the pain associated with propofol infusion. Vibration is proposed to stimulate A-beta nerve fibers, which transmit information from vibration and touch which, according to the Gate Control Theory of Pain (Melzack and Wall 1965), inhibits signal transduction by A-delta and C fibers (Kakigi and Shibasaki 1992). Vibration has been demonstrated to be effective to decrease pain during vaccinations, phlebotomy, and dental anesthesia (Baxter et al. 2011; Nanitsos et al. 2009). In this study, the investigators seek to evaluate the role of vibration in the reduction of discomfort associated with painful stimulus associated with anesthesia induction. Through this study, the investigators hope to develop a comprehensive and cost-effective approach to minimize patient discomfort during anesthesia induction. Study Design The objective of this study is to evaluate the effectiveness of vibration as a analgesic during induction of anesthesia. It is the investigators hypothesis that both vibration will lessen the pain of propofol infusion. Patients set to receive a propofol infusion as part of induction of anesthesia during surgery will be recruited to participate in this study. All participating patients will be randomized following acquisition of consent for study participation to one of two intervention groups: 1) normal standard of care infusion of propofol without analgesia 2) infusion of propofol with application of vibration analgesia. Patients will then be asked to place a mark on a 100-mm visual analogue scale corresponding to the level of pain that they experienced during the digital block. Additionally, Please see the next section for specific details regarding the intervention. Due to constraints regarding the validity of the linear visual analogue scale in very young patients (Stinson et al. 2006), only those aged 18 years or older will be eligible for participation in the study. Parents or guardians will provide consent for minors or for individuals who are otherwise unable to provide consent themselves.

Risks associated with the BUZZY(tm) device The intervention group will receive vibration only, with application of the BUZZY device just proximal to the intravenous infusion site immediately before and during propofol infusion. There are no known risks for the use of the BUZZY(tm) device, which is registered as an FDA class III device ("therapeutic massager").

Level of Pain as Observed by Two Independent Observers Following Propofol Injection, With or Without a Vibration Analgesia Adjunct

Patient pain will be assessed by two independent observers, an attending anesthesiologist and a certified registered nurse anesthetist (CRNA). Pain was graded using a four-point pain manifestation scale described by McCrirrick & Hunter : 0 = none (negative response to questioning), 1 = mild (pain reported in response to questioning only, without any behavioral signs), 2 = moderate (pain reported in response to questioning and accompanied by a behavioral sign, or pain reported spontaneously without questioning), 3 = severe (strong vocal response or response accompanied by facial grimacing, arm withdrawal or tears). Higher scores meaning worse outcome (perceived pain) and lower score meaning better outcome.

Inclusion Criteria: Those aged 18 to 100 who are going to receive propofol injection as part of induction of anesthesia for surgery Exclusion Criteria: Those below the age of 18

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