Dexmedetomidine as an Adjunct to Transversus Abdominis Plane Block in Patients Undergoing Cancer Surgeries: A...

Cancer rates are increasing significantly worldwide, with surgical intervention being the most convenient intervention. Transversus abdominis plane (TAP) block has been proven to enhance postoperative opioid use and its associated complications. Additionally, dexmedetomidine has been reported to provide effective analgesia with relatively minimal respiratory complications. This systematic review and meta-analysis aims to explore the efficacy of combining dexmedetomidine with transversus abdominis plane (TAP) block compared to transversus abdominis plane (TAP) block alone in patients undergoing various cancer surgeries as outcomes may also be influenced by surgical and patient-related factors.

We conducted a comprehensive literature search across PubMed/MEDLINE, Scopus, Web of Science, Cochrane CENTRAL, and Embase to identify randomized controlled trials evaluating the efficacy and safety of dexmedetomidine as an adjunct to transversus abdominis plane (TAP) block in patients undergoing cancer surgery. Data were extracted from the six eligible randomized controlled trials that met the predefined inclusion criteria, and a random-effects meta-analysis was performed using RevMan software Version 5.4.

The meta-analysis found that dexmedetomidine as an adjunct to transversus abdominis plane (TAP) block was more effective than transversus abdominis plane (TAP) block alone in reducing the mean arterial pressure and the mean heart rate 2 h postoperatively (MD -6.46, 95% CI [-8.63; -4.30], p < 0.0001) and (MD -5.44, 95% CI [-7.67; -3.20], p < 0.0001). The duration until the first rescue analgesia was significantly longer in the TAP-DEX group (MD 3.75, 95% CI [3.08; 4.43], p < 0.0001). The overall patient satisfaction with postoperative pain management demonstrated statistically significant improvement compared to the TAP group (RR 1.31, 95% CI [1.13; 1.53], p = 0.0005). visual analog scale (VAS) pain scores, which are used to assess pain intensity, were significantly lower at rest and during movement 2 h postoperatively in the TAP-DEX group, although some complex patients may have difficulty using visual analog scale (VAS) pain scores accurately. Therefore, the Numeric Rating Scale (NRS) may be considered as an alternative tool.

Compared to transversus abdominis plane (TAP) block alone, the dexmedetomidine and transversus abdominis plane (TAP) block arm showed a statistically significant difference in time to first rescue analgesia, patient overall satisfaction, nausea, and vomiting. However, no statistical significance difference was found across the remaining outcomes.