Intraoperative dexemdetomidine (DEX) with or without loading dose is well-established to improve postoperative pain control in patient-controlled analgesia (PCA). This study was designed to compare the pro-analgesia effect between the 2 in patients received general anesthesia.
Seventy patients shceduced abdominal surgery under general anesthesia were randomly assigned into 3 groups which were maintained using propofol/remifentanil/Ringer solution (PRR), propofol/remifentanil/dexmedetomidine with (PRDw) or without (PRDo) a loading dose of dexmedetomidine before induction.
PRDw/o patients displayed a greater Romsay sedation score measured immediately after surgery. When compared with PRR patients, those from the PRDw/o group had an increased time to first request of postoperative morphine and decreased 24 hours total morphine consumption. No significant difference was observed between patients from the PRDw and PRDo groups with respect to these parameters.
The present study suggests that the administration of a DEX loading dose does not affect the pro-analgesic effect of intraoperative use of DEX on morphine-based PCA.