Efficacy of dexmedetomidine combined with sufentanil for patient-controlled intravenous analgesia after caeserean section / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the efficacy of dexmedetomidine combined with sufentanil for patientcontrolled intravenous analgesia (PCIA) after caeserean section. Methods One hundred and twenty parturients aged 18-40 yr undergoing caeserean section under spinal-epidural anesthesia were randomly assigned to one of 3 groups( n=40 each)group Ⅰ , group Ⅱ and group Ⅲ . During operation as soon as the baby was bom a bolus of dexmedetomidine 0.5 μg/kg was given iv in Ⅱ and Ⅲ groups while in group Ⅰ normal saline (NS) was given instead. Ⅰ and Ⅱ groups received PCIA with sufentanil (background infusion 0.015 μg·kg-1·h-1;bolus dose 0.023 μg/kg;lockout interval 8 min). Group Ⅲ received PCIA with sufentanil + dexmedetomidine (background infusion sufentanil 0.015 μg·kg-1 ·h-1 + dexmedetomidine 0.045 μg·kg· h-1;bolus dose sufentanil 0.023 μg/kg + dexmedetomidine 0.07 μg/kg;lockout interval 8 min) . Pain threshold and pain tolerance threshold were measured before caeserean section and 1 h after bolus dose of dexmedetomidine or NS. VAS, OAA/S and satisfaction scores and sufentanil consumption were recorded at 4, 8 and 24 h after operation.Blood samples were obtained before anesthesia,1 h after bolus injection of dexmedetomidine, and 24 h after operation for determination of serumcortisol concentration. Results Pain threshold and pain tolerance threshold at 1 h after bolus injection of dexmedetomidine were significantly increased as compared with the baseline before anesthesia in Ⅱ and Ⅲ groups and were significantly higher in Ⅱ and Ⅲ groups than in group Ⅰ . VAS scores and the consumption of sufentanil were significantly lower while the satisfactory score was significantly higher in group Ⅲ than in Ⅰ and Ⅱ groups. Serum cortisol concentrations were significantly increased at 1 h after iv dexmedetomidine or NS injection as compared with the baseline before anesthesia in all 3 groups, but there was no significant difference in serum cortisol levels among the 3 groups. Conclusion Addition of dexmedetomidine to sufentanil for PCIA can significantly reduce the consumption of sufentanil and improve parturient's satisfaction.