Effect of dexmedetomidine-ropivacaine transversus abdominis plane block on analgesia and cognitive impairment risk in colorectal cancer surgery.

Abstract

Background: The dexmedetomidine (DEX) plus ropivacaine treatment enables a transversus abdominis plane block (TAPB) of the peripheral nerves in patients undergoing radical resection for colorectal cancer (CRC) that can provide clinical data for improving the postoperative analgesic effect, reducing the risk of cognitive impairment, and decreasing the circulating levels of serum inflammatory factors and stress hormones.

Aim: To assess the impact of DEX plus ropivacaine-enabled TAPB on pain, postoperative cognitive dysfunction (POCD), and inflammatory/stress factors.

Methods: Our patient cohort was randomly divided into control and observation groups (60/group). The observation group used a DEX plus ropivacaine-enabled TAPB, while the control group employed a ropivacaine-enabled TAPB. The pain score [Visual Analogy Scale (VAS), Montreal Cognitive Assessment (MoCA)], serum inflammatory factor level (C-reactive protein, interleukin-6 and tumor necrosis factor-α), serum stress hormone levels (cortisol and adrenaline) and postoperative adverse reactions were compared between the two groups.

Results: The observation group VAS scores were lower than those of the control group (better analgesic effect, P < 0.05). The MoCA and POCD scores decreased post-surgery in the observation group (P < 0.05). In the elderly, the overall VAS and MoCA scores were significantly reduced compared with the young group. The C-reactive protein, interleukin-6, tumor necrosis factor-α, cortisol and adrenaline levels were lower in the observation group compared with the control group post-surgery (P < 0.05). There was no significant difference in adverse reactions between the two groups post-surgery, but the incidence of adverse reactions in the observation group was still lower. DEX continuously inhibited p65-phosphorylation levels in the nuclear factor κB pathway at multiple time points, and its inhibitory effect became more significant over time.

Conclusion: DEX plus ropivacaine-enabled TAPB reduces POCD and inflammatory/stress hormone levels, and significantly improves the postoperative analgesic effect of patients undergoing radical resection for colorectal cancer.