Clinic Observation Of Dexmedetomidine Combined With Ropivacaine For The Ultrasound-Guided Transversus Abdominis Plane Block In Children

Objective To evaluate the efficacy and safety of dexmedetomidine combined with ropivacaine for the ultrasound-guided transversus abdominis plane block (TAP block) in children.Methods A total of 69 children scheduled for laparotomy, aged 1-8 years, ASA II, were randomly divided into 3 groups:(1) general anesthesia group (group A,n=23); (2) 0.375% ropivacaine for TAP block group (group B,n=23); (3) 0.25μg/Kg dexmedetomidine combined with 0.375% ropivacaine for TAP block (group C,n=23). The vital signs were recorded at six time points during surgery:preaneasthesia (T1), the end of the nerve block or anesthesia induction (T2), the skin incision (T3), cutting abdominal muscle (T4), cutting parietal peritoneum(T5) and extubation time(T6). The anesthetic consumption (propofol, remifentani and fentanyl),anesthesia duration, operative time and residence time in Postanesthesia Care Unit (PACU) were also recorded. The incidence of emergence agitation (EA) was assessed with pediatric anesthesia emergence delirium (PAED) scale. The Face Legs Activity Consolability (FLACC) scale was assessed at return to the ward,2h,4h,6h,12h and 24h postoperatively. The pulses were recorded at eleven time points after operation:return to the ward,2h,4h,6h,12h,20h,24h,36h,48h,60h and 72h postoperatively. Any complications of the TAP block were recorded. The number of children requiring analgesia after operaion was counted. The postoperative fasting and water deprivation duration and hospitalization duration were also recorded.Results The propofol and remifentani comsumption of Group A were significantly larger than those in Group B and Group C (P<0.05). The PAED scals and FLACC scores in the Group B and Group C were lower than Group A, and Group C was lower than Group B (P<0.05). The HR, MAP at T4 and T5 in Group C were significantly lower than those in Group A (P<0.05). The HR at T6 and the MAP at T5 in Group B and Group C were also lower than those in Group A (P<0.05). Compared with T2, the HR and MAP at T3,T4,T5 in Group A were increased (P<0.05); the HR and MAP at T3,T4,T5 in Group B and Group C were no significant change(P>0.05). Compared to Group A, the pulses at postoperative 4h,6h and 48h of Group B were lower; those of Group C at return to the ward,postoperative 2h,4h,6h and 36h were lower significantly (P<0.05). The pulses of Group A were decreased (P<0.05) but the other two groups were no significant change (P>0.05).Any complications related to the TAP block hasn’t occurred.Conclusion The ultrasound-guided transversus abdominis plane block can be used for laparotomy in children safely and provide satisfactory analgesia of abdominal wall during the operation period. The 0.375% ropivacaine for TAP block can provide 24h postoperative analgesia. The analgesic effect of 0.25μg/Kg dexmedetomidine combined with 0.375% ropivacaine for TAP block is better than 0.375% ropivacaine. It can also delay the first time of using postoperative analgesia drug.