A Randomized, Controlled Trial on Dexmedetomidine for Providing Adequate Sedation and Hemodynamic Control for Awake, Diagnostic Transesophageal Echocardiography

Objective: Transesophageal echocardiography (TEE) has become established as a sensitive and accurate diagnostic method for the rapid assessment of myocardial function. It was theorized that dexmedetomidine (Precedex; Hospira, Inc, Lake Forest, IL) might prove to be useful for sedating patients while undergoing TEE. Design: A prospective, randomized trial was designed comparing dexmedetomidine versus standard therapy (eg, midazolam and opioids) for sedation. Setting: This trial was performed in a tertiary care, single-institution university hospital. Participants: Males and females, American Society of Anesthesiologists I to IV, ages 18 to 65 years, requiring diagnostic TEE. Patients were excluded if pregnant, if they had taken benzodiazepines or opioids within 24 hours, or if they were deemed to be too unstable to receive any kind of sedation. Interventions: Patients were randomized to standard therapy or dexmedetomidine infusion groups. Sedation was assessed at 6 time points. Pulse oximetry, electrocardiogram, heart rate, noninvasive blood pressure, and respiratory rate were monitored. Additional variables measured were the amount of each drug given, the time of the TEE procedure, and the time to recovery. Measurements and Main Results:A survey about the quality of sedation, the level of comfort, and whether or not they would accept this type of sedation again was administered after recovery from sedation. Demographic data and patient questionnaire responses were reported as means and standard errors or percents and were analyzed with the t test and chi-square test. Twenty-two patients were enrolled. Hemodynamics were statistically different between the two groups at several time points. Both systolic and diastolic blood pressures (BP) were elevated in the standard therapy group, whereas the dexmedetomidine group had a lower BP. Heart rate was elevated significantly in the standard therapy group compared with the dexmedetomidine group. There was no statistical or clinical difference between the groups in terms of oxygenation or respiratory rate. Conclusions: The authors concluded that dexmedetomidine appears equivalent in achieving adequate levels of sedation without increasing the rate of respiratory depression or decreasing oxygen saturation compared with standard therapy, and it may be better in achieving desired hemodynamic results. (C) 2011 Elsevier Inc. All rights reserved.