A Study Comparing The Analgesic Efficacy And Side Effects Of Different Concentrations Of Ropivacaine With/without Dexmedetomidine In PPH Surgery Undergoing Caudal Blokade

Background:Caudal blockade is a common procedure for adult patients undergoing PPH surgery. We studied the clinical outcomes and urinary retention occurrence rate of the different concentrations of ropivacaine with/without dexmedetomidine to draw a conclusion that which concentration of anesthetic was more suitable for PPH surgery.Methods:People who underwent elective PPH surgery from January to May 2014 were included in the study (n=164). Patients were randomly assigned to four groups of different concentrations of ropivacaine with/without dexmedetomidine. GroupRo.25: 0.25% ropivacaine (Group 1), GroupRo.2sD:0.25% ropivacaine plus 1μg/kg dexmedetomidine (Group 2), GroupRo.375:0.375% ropivacaine (Group 3) and GroupRo 375D:0.375% ropivacaine plus 1μg/kg dexmedetomidine (Group 4). The total volume is 20ml. We compared the onset time of anesthesia, motor block, hemodynamic changes, anesthetic effect, postoperative analgesia, and the occurrence rate of urinary retention between the four groups.Results:The onset time of anesthesia was significantly more rapid in the group R0.25 D, group R0.375 and group R0.375D than in group R0.25 (PO.05). And there were no statistical differences between R0.25D, R0.375 and R0.375D groups. The score of anesthetic effect was higher in the group R0.25 D, group R0.375 and group R0.375D than in group R0.25 (P<0.05). And there were no statistical differences between R0.25 D, R0.375 and R0.375D groups. There were no statistical differences between the four groups in the hemodynamic changes and motor block. Patients in the group R0.25 D, group R0.375 and group R0.375D demonstrated significantly lower VAS scores after surgery compared with patients in group R0.25 (P<0.05). And there were no statistical differences between the group R0.25D, group R0.375 and group R0.375D. The urinary retention occurrence rate were significantly lower in the group R0.25 and group R0.25 D than that in the group R0.375 and group R0.375D, there was no statistical difference between the group R0.25 and group R0.25D and between the group R0.375 and group Ro.37sD-Conclusion:lug/kg dexmedetomidine with 0.25% ropivacaine in CB results in a shorter onset time, more effective anesthetic effect and reduction of post-operative pain, The analgesic effect of the combination is similar with the common clinical concentration of 0.375% ropivacaine, and lower occurrence of urinary retention.less impact on motor block and Hemodynamic changes. The results of this study suggest that 1ug/kg, dexmedetomidine combined with 0.25% ropivacaine is safe and effective for PPH of Caudal block.