Searching Optimal Target of Perfusion Pressure for Managing Acute Kidney Injury in Critically Ill Patients: An Analysis of Three Large Open Databases

Background: The optimal perfusion pressure target for acute kidney injury (AKI) in critically ill patients remains uncertain. We investigated the association between mean perfusion pressure (MPP) and AKI among critically ill patients and estimated its optimal range.Methods: We analyzed data stored in the Medical Information Mart for Intensive Care (MIMIC) -III, eICU Collaborative Research Database (eICU-CRD), and MIMIC-IV databases. Critically ill patients receiving invasive measurements of MPP for at least 12 hours within the first 24 hours of ICU stay were included. The exposure of interest was the time-weighted average MPP (TWA-MPP) in the first 24 hours. The primary outcome was the incidence of AKI in the next 48 hours. Results: We enrolled 7,992, 8,604, and 6,730 patients from the MIMIC-III, eICU-CRD, and MIMIC-IV databases, respectively. TWA-MPP had higher areas under the curve than mean arterial pressure in predicting AKI in the next 48 hours (0.63 vs 0.57, 0.62 vs 0.58, and 0.64 vs 0.58 in three databases, all p < 0.001). We observed the lowest adjusted risk of AKI when TWA-MPP above 72, 65, and 69 mmHg in the MIMIC-III, eICU-CRD, and MIMIC-IV databases, respectively. Pooled analyses indicated that per 10% increase of proportion of MPP above 65 mmHg was associated with decreased incidence of AKI (adjusted odds ratio = 0.93, 95% confidence interval = 0.92–0.94, p < 0.001). Furthermore, pooled analyses showed that the lowest risk of new-onset, persistence, and progression of AKI was estimated when TWA-MPP above 74, 70 and 65 mmHg, respectively. Conclusions: MPP outperformed mean arterial pressure as a perfusion predictor of AKI. MPP of 65 mmHg or higher may be the optimal target for managing AKI in critically ill patients. The target rises to higher when reversing or preventing AKI.