Effect of dexmedetomidine added to ropivacaine on ultrasound-guided transversus abdominis plane block for postoperative analgesia after abdominal hysterectomy surgery: a prospective randomized controlled trial.

Background: To identify the effect of dexmedetomidine added to ropivacaine on ultrasound-guided transversus abdominis plane block for postoperative analgesia after abdominal hysterectomy surgery.

Methods: Sixty patients were enrolled in the study and divided into two groups. Bilateral 20 mL 0.3% ropivacaine and 2 mL 0.9% normal saline for ropivacaine group (group R), and bilateral 20 mL 0.3% ropivacaine and 2 mL dexmedetomidine (0.5 µg/kg) for dexmedetomidine group (group RD). Visual Analogue Scale (VAS) pain scores, frequency of PCA pressed, sufentanil consumption, and postoperative nausea and vomiting (PONV) were recorded.

Results: There was no significant difference in VAS pain scores between the two groups at different time intervals (P>0.05). Compared with group RD, the frequency of PCA pressed and integrated consumption of sufentanil were significantly higher in Group R at 0-2, 2-4, 4-6, 6-8, time intervals (P<0.05) except for 8-12,12-24 time intervals (P>0.05), and the 24h total sufentanil consumption and frequency of PCA pressed were also higher in group R (63.9±10.0 vs. 51.8±9.1, 8.3±1.7 vs. 5.4±1.6) (P<0.05). There was no difference in PONV between the two groups (P>0.05).

Conclusions: Ultrasound-guided TAP block could be as an effective component of multimodal postoperative analgesic regimen; adding dexmedetomidine to ropivacaine in TAP block potentiated the analgesic properties of ropivacaine, reduced sufentanil consumption and provided better pain control after abdominal hysterectomy surgery.