Propofol and Dexmedetomidine Versus a Propofol Only Regimen for Sedation During Colonoscopy
Condition: Colonoscopy
Study type: Interventional
Phase: Phase 4

Summary: 
      An ideal sedative for colonoscopy should have properties that include: rapid onset and offset
      of action, provide cardiopulmonary stability, have minimal adverse effects, and allow for
      smooth recovery, and early discharge. Propofol is often used solely because of its rapid
      onset and short duration of action---a property which is ideal for a fast recovery and early
      discharge in the ambulatory setting. However, the use of propofol has been associated with
      undesirable effects such as hypotension, hypoventilation and apnea requiring assisted
      ventilation.

      Balanced anesthesia, using a combination of medications with different mechanisms of action
      can reduce the total amount of each sedative agent used and minimize their side effects while
      achieving the desired level of sedation. Dexmedetomidine is one agent that has been used
      either alone or in combination with propofol for sedation during colonoscopy. While there are
      many advantages to using dexmedetomidine, there is concern that the use of this agent for
      sedation during colonoscopy may prolong post-operative recovery time and readiness for
      discharge home.

      No study has definitively assessed whether the use of dexmedetomidine in combination with
      propofol during ambulatory colonoscopy prolongs post-operative recovery time as determined by
      the Modified Post Anesthesia Discharge Scoring System (MPADSS).
    

Detailed description: 
      In this study, investigators plan to prospectively compare in a randomized, controlled,
      double-blind trial, the sedation technique for colonoscopy between two groups. Group 1:
      sedation with dexmedetomidine and propopfol versus group 2: sedation with saline placebo and
      propofol.

      The study will have the following outcome measures for each group.

      Primary outcome measure:

      Readiness-for-discharge (RFD) at 10, 20 and 30 minutes after the colonoscopic procedure.
      Ready-for-discharge is defined as attainment of MPADSS score of 9-10.

      Secondary outcome measures:

        1. Total propofol consumption in mg/kg/duration of procedure in minutes;

        2. Side effects:

             1. lowest intraoperative percent (%) drop in mean arterial pressure (MAP) from
                baseline,

             2. incidence of sustained bradycardic episodes (HR<50 for at least 5 minutes)
                intraoperatively,

             3. incidence of apneic episodes intraoperatively requiring positive pressure
                ventilation.

      Methods:

      One hundred patients will be recruited and randomized into two groups. For sedation, Group 1
      will receive intravenous dexmedetomidine 0.3 ug/kg bolused at the onset of the procedure
      followed by titrated doses of propofol. Group 2 will receive a saline placebo bolus at the
      onset of the procedure followed by titrated doses of propofol. A hospital research
      pharmacist, based on a randomization table, will allocate to the anesthesia provider giving
      the sedation, the bolus syringe labelled dexmedetomidine/or saline study agent. The
      anesthesia provider, gastroenterologist, nurses as well as the subject will be blinded as to
      the syringe's actual content. A Bispectral Index (BIS) Monitor will be used during sedation.
      All subjects will be targeted to maintain a BIS score between 60-70. Outcome measures will be
      evaluated for statistical significance in a non-inferiority assessment.

      Investigators hypothesize that there will be no difference in the time to discharge between
      the two treatment groups.
    

Intervention name(s): Dexmedetomidine; Saline placebo; Propofol
Intervention type(s): Drug; Other; Drug
Intervention description(s): Dexmedetomidine 0.3 ug/kg intravenous bolus; Intravenous saline/placebo; Propofol titrated intravenous boluses
Other intervention name(s): Dex; Precedex; Diprivan
Intervention MeSH terms: Dexmedetomidine; Propofol
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Care Provider)
Primary purpose: Supportive Care