Predictive Value of Veno-Arterial Carbon Dioxide Difference[P(cv-a)CO2]Combined with RRI for Acute Kidney Injury in Septic Shock Patients

ZHANG Cheng

doi:10.14033/j.cnki.cfmr.2026.05.003

Abstract：Objective:To investigate the early predictive value of the veno-arterial carbon dioxide difference[P(cv-a)CO2]combined with the renal resistive index(RRI)for acute kidney injury(AKI)in patients with septic shock.Method:A total of 48 patients with septic shock admitted to Sanming First Hospital Affiliated to Fujian Medical University from June 2024 to June 2025 were selected as the research subjects.They were divided into the AKI group(18 cases)and the non-AKI group(30 cases)according to whether AKI occurred.P(cv-a)CO2 and RRI were detected at 1 hour and 3 hours after admission to the ICU,respectively.The differences between the two groups were compared,and the predictive efficacy of each index and the combined index for AKI was analyzed through the receiver operating characteristic(ROC)curve.Result:At 3 hours of ICU admission,the P(cv-a)CO2 and RRI in the AKI group were significantly higher than those in the non-AKI group,and the difference was statistically significant(P＜0.05).The area under the curve(AUC)of P(cv-a)CO2 for predicting AKI was 0.860(95％CI:0.757～0.963),the optimal cut-off value was 6.5 mmHg,the sensitivity was 72.2％,and the specificity was 83.3％.The AUC of RRI for predicting AKI was 0.840(95％CI:0.706～0.973),the optimal cut-off value was 0.66,the sensitivity was 77.8％,and the specificity was 83.3％.The AUC of the combined prediction of the two increased to 0.925(95％CI:0.844～1.000),with a sensitivity of 88.9％and a specificity of 90.0％.Conclusion:In patients with septic shock,early combined monitoring of P(cv-a)CO2 and RRI can significantly improve the predictive accuracy of AKI,has a good clinical application prospect,and is conducive to achieving earlier risk assessment and intervention.