Influence of Intraoperative Analgesia on the Postoperative Morphine Consumption
Unlike longer acting opiates (sufentanil), remifentanil may provoke postoperative hyperalgesia. We have developed two automated bispectral index - guided drug delivery systems: one for propofol administration, the other for combined propofol and remifentanil administration. Both systems achieve the same objective: similar level of anesthesia indicated by bispectral index levels between 40 to 60. We make the assumption that this method of automated remifentanil administration may avoid postoperative hyperalgesia. Patients scheduled for abdominal surgery will be divided into two groups:
- in one group, patients will receive automatically delivered propofol and manually delivered sufentanil according to the usual criteria,
- in the other group, patients will receive propofol and remifentanil both automatically administered.
Assessment of postoperative hyperalgesia will be primarily based on morphine consumption (patient controlled analgesia) and detection of cutaneous hyperalgesia areas.
|Study Design:||Allocation: Randomized
Endpoint Classification: Pharmacodynamics Study
Intervention Model: Parallel Assignment
Masking: Single Blind (Subject)
Primary Purpose: Basic Science
|Official Title:||Influence of Intraoperative Analgesia (Sufentanil Administered According to the Usual Criteria or Remifentanil Administered by a Closed-loop System Using Bispectral Index as the Controller) on the Postoperative Morphine Consumption|
- Dose of morphine administered during the postoperative period (patient controlled analgesia) [ Time Frame: 48 postoperative hours ] [ Designated as safety issue: No ]
- postoperative pain scores [ Time Frame: 48 postoperative hours ] [ Designated as safety issue: No ]
- postoperative hyperalgesia [ Time Frame: up to 5th to 7th postoperative days ] [ Designated as safety issue: No ]
- nausea vomiting [ Time Frame: 48 postoperative hours ] [ Designated as safety issue: No ]
|Study Start Date:||September 2008|
|Study Completion Date:||January 2011|
|Primary Completion Date:||January 2010 (Final data collection date for primary outcome measure)|
Patients will receive propofol and remifentanil automatically administered (closed-loop administration using bispectral index as the single input for the controller).
closed-loop administration using bispectral index as the single input for the controller.
Active Comparator: 2
Patients will receive propofol automatically administered (closed-loop administration using bispectral index as the single input for the controller) and sufentanil according to usual criteria
dosage according to usual criteria