Intraoperative arterial blood pressure waveform variation predicts short-term acute kidney injury after cardiac surgery

BackgroundArterial blood pressure (ABP) waveforms are ever-changing. Variation in waveform morphology (VarM) may reflect the complex interactions of cardiovascular regulatory mechanisms. We investigated the association between VarM and the development of acute kidney injury (AKI) following cardiac surgery. MethodsIn tahis prospective observational single-cohort study, 101 patients undergoing elective cardiac surgery involving cardiopulmonary bypass (CPB) were enrolled. VarM was quantified from consecutive ABP waveform pulses. Postoperative AKI was defined using serum creatinine levels according to the KDIGO criteria. ResultsAfter weaning from CPB, AKI group showed a lower VarM index and a lower trend. In the presence of baseline renal function, EuroSCORE, and CPB duration, VarM provided additional predictive value for identifying patients at risk of AKI (AUROC: 0.775 vs. 0.762). ConclusionsVarM derived from the ABP waveform following CPB is associated with the incidence of short-term postoperative AKI. Key Points SummaryO_ST_ABSQuestionC_ST_ABSIs intraoperative variation of arterial blood pressure waveform morphology (VarM) associated with postoperative acute kidney injury (AKI) in elective cardiac surgery? FindingsA lower VarM value and a lower trend after CPB weaning were associated with AKI, and combining VarM to baseline eGFR, EuroSCORE, and CPB time improved discrimination (AUC 0.775) compared with models without VarM and outperformed standard vital-sign metrics. MeaningBeat-to-beat arterial blood pressure waveforms reflect the unique state of the cardiovascular system relevant to AKI after cardiac surgery.