Low-dose intrathecal clonidine combined with sufentanil as analgesic drugs in abdominal gynecological surgery.

STUDY OBJECTIVES: To determine whether a low dose of spinal clonidine either alone or combined with sufentanil would provide effective analgesia following abdominal surgery, as a supplement to bupivacaine spinal anesthesia.

DESIGN: Randomized double-blind study.

SETTING: Gynecological surgery, teaching hospital.

PATIENTS: 73 ASA physical status I and II patients undergoing gynecological abdominal surgery with spinal anesthesia.

INTERVENTIONS: Patients were randomly assigned to one of four groups and prospectively studied to examine anesthesia, analgesia, and adverse effects. The control group received saline as the test drug; the sufentanil group received 10 microg of sufentanil; the clonidine group received 30 microg of clonidine; and the sufentanil/clonidine group received 5 microg of sufentanil plus 15 microg of clonidine. All groups received intrathecal 15 mg of bupivacaine (3 mL) plus the intrathecal test drug (2 mL). The concept of visual analog scale (VAS) was introduced. All patients were premedicated with intravenous midazolam. Rescue analgesics were available.

MEASUREMENTS AND MAIN RESULTS: The groups were demographically the same. Sensory block to pinprick at 10 min was higher for clonidine and sufentanil/clonidine groups compared to the control group (p < 0.02). Anesthetic time (Bromage score 2) was also longer for clonidine and sufentanil/clonidine groups compared to the control and sufentanil groups (p < 0.05). Time to first rescue analgesics was shorter in the control group compared to the other groups (p < 0.02). The number of IM diclofenac dose injections in 24 hours was higher in the control group compared to all other groups (p < 0.05). The incidence of adverse effects and ephedrine consumption were similar among groups.

CONCLUSIONS: Intrathecal 15- and 30-microg clonidine doses expanded the anesthesia sensory block and duration of motor block, and provided analgesia.