Effect of Individualized versus Standard Intraoperative Blood Pressure Management on Acute Kidney Injury in Patients with Hypertension Undergoing Abdominal Surgery: A Randomized Clinical Trial

Background: Intraoperative hypotension is associated with postoperative acute kidney injury (AKI), but the optimal intraoperative blood pressure target for patients with hypertension remains uncertain. The authors hypothesized that individualized blood pressure management based on each patient’s preoperative baseline blood measure would reduce the incidence of postoperative AKI compared with standard blood pressure management. Methods: In this randomized clinical trial, the authors enrolled adult patients with a history of hypertension scheduled for elective major abdominal surgery expected to last more than 3 h. Patients were randomly assigned in a 1:1 ratio to individualized or standard intraoperative blood pressure management. In the individualized group, anesthesiologists targeted a mean arterial pressure (MAP) within ±10% of the preoperative baseline MAP; in the standard group, MAP was maintained at 65 mmHg or higher. The primary outcome was the incidence of AKI within 7 days after surgery. Secondary outcomes included the incidence of AKI (stage 2 or greater), initiation of renal replacement therapy, and an ordinal analysis of AKI severity. Results: Of the 400 randomized patients, 381 were included in the final analysis (191 individualized, 190 standard). Intraoperative MAP was higher in the individualized group (84 [79 to 89] vs. 78 [74 to 83] mmHg; P < 0.0001), and the cumulative duration of MAP less than 65 mmHg was shorter (10 [3 to 28] vs. 27 [9 to 64] min; P < 0.0001). Postoperative AKI occurred in 25 of 191 patients (13.1%) in the individualized group and 29 of 190 patients (15.3%) in the standard group (risk ratio: 0.85; 95% CI: 0.52 to 1.41; P = 0.543). Secondary renal outcomes did not differ significantly between groups. Conclusions: In patients with treated hypertension and preserved renal function undergoing prolonged elective abdominal surgery, individualized intraoperative blood pressure management increased MAP and reduced intraoperative hypotension but did not reduce the incidence or severity of postoperative AKI compared with standard blood pressure management.