Add dexmedetomidine to levobupivacaine for transversus abdominis plane block in elderly patients undergoing inguinal hernia repair: Could it make a difference? A randomised trial.

BACKGROUND: Transversus abdominis plane block is becoming more common as part of multimodal analgesia for post-abdominal operation pain relief. This study compared the analgesic effects of adding dexmedetomidine to levobupivacaine (transversus abdominis plane) block in elderly patients undergoing inguinal hernia surgery to adding fentanyl.

METHODS: Overall, 90 elderly patients with a simple inguinal hernia repair were randomly assigned to one of three groups. After spinal anaesthesia, an ultrasound-guided transversus abdominis plane block was performed. Transversus abdominis plane block was accomplished with 0.25% levobupivacaine + 0.9% normal saline in Group L (n = 30) (20mL). Transversus abdominis plane block was accomplished with 0.25% levobupivacaine + 1 µg/kg dexmedetomidine in Group D (n = 30) (20mL). Transversus abdominis plane block was obtained with 0.25% levobupivacaine + 1 µg/kg fentanyl in Group F (n = 30) (20mL). The primary outcome was the first analgesic request, and the secondary outcomes were the visual analog scale, postoperative analgesic requirements, sedation, hemodynamic stability, and related complications 24 hours postoperatively. 1gm paracetamol intravenously was provided as rescue analgesia.

RESULTS: The time to first analgesic request in the dexmedetomidine group was substantially more prolonged than in the fentanyl and control groups (516.5±27.8, 451.2±11.1, and 403.9±10.5min, respectively; p < 0.05). Postoperative analgesic requirements were significantly decreased in dexmedetomidine 1(1-2) than control 2(1-3) and fentanyl 1.5(1-2) respectively (P<0.01). VAS was significantly lower in Group D and Group F than in Group L postoperatively. No significant difference in side effects was noted between the groups.

CONCLUSION: The transversus abdominis plane block is the best multimodal analgesia choice for inguinal hernia repair in older patients. Combining dexmedetomidine with levobupivacaine in the transversus abdominis plane block can improve the quality of postoperative analgesia while avoiding significant side effects.