Preemptive left stellate ganglion block reduces the incidence and severity of cardiac surgery-associated acute kidney injury: a randomized clinical trial

BACKGROUND: Acute kidney injury is a common and severe complication of cardiac surgery. A connection might exist between renal sympathetic nerves and left stellate ganglion. It remains unclear whether preemptive left stellate ganglion block (SGB) can effectively prevent cardiac surgery-associated acute kidney injury (CSA-AKI) in clinical practice. METHOD: Participants were randomly assigned to SGB group with 0.375% ropivacaine 5 ml performed post-general anesthesia induction or control group (no SGB). The primary outcomes were incidence and severity of CSA-AKI within 7 days postoperatively. Secondary outcomes were intraoperative resistive index (RI) and pulsatility index (PI) of left renal artery via TEE and perioperative IL-6, CRP, and norepinephrine. RR and 95% CI were calculated to compare outcomes between groups. Sensitivity analyses were performed to confirm robustness of findings. RESULT: A total of 138 participants were randomized for intention-to-treat (ITT) analysis (69 SGB, 69 control) and 119 for per-protocol (PP) analysis (59 SGB, 60 control). In the ITT analysis, the incidence of CSA-AKI was significantly lower in the SGB group than the control group (14.5% [10/69] vs. 40.6% [28/69], RR 0.351, 95% CI: 0.169-0.728, P = 0.005). The PP analyses (13.6% [8/59] vs. 41.7% [25/60], RR 0.325, 95% CI: 0.160-0.660, P = 0.001) demonstrated similar results. The severity of CSA-AKI was significantly lower in the SGB group than the control group (ITT and PP: P < 0.001). The RI and PI were significantly lower in the SGB group than the control group at post-CPB cessation ( P < 0.001 and P = 0.005, respectively). Postoperatively, the SGB group demonstrated significant reductions in IL-6, CRP, and norepinephrine (all P < 0.05). The sensitivity analysis confirmed the robustness of the observed effects, yielding an unadjusted benefit ratio of 0.244 (95% CI: 0.096-0.620, P = 0.003) for the incidence of CSA-AKI and 0.197 (95% CI: 0.082-0.468, P < 0.001) for its severity. CONCLUSION: Preemptive left SGB effectively reduces the incidence and severity of CSA-AKI in patients undergoing cardiac surgery under CPB.