Feasibility Study of Renal Negative Pressure Treatment After Cardiac Surgery With Cardiopulmonary Bypass.

BACKGROUND: We conducted a technical feasibility and safety study of intraureteric renal negative pressure treatment (rNPT) in patients with chronic kidney disease undergoing elective cardiac surgery with cardiopulmonary bypass. METHODS: After written informed consent, 10 patients with preoperative estimated glomerular filtration rate of 15 to 59 mL/min per 1.73 m2 were enrolled at 3 sites. At the end of surgery, a urologist advanced a specialized ureteral catheter into each renal pelvis under radiographic guidance. Intra.renal negative pressure of -15 mm Hg was initiated postoperatively and continued for 24 hours. Patients were followed up on postoperative days 14 and 28. RESULTS: Three patients had major protocol deviations with primary catheter misplacement; acute kidney injury developed in 1 of these. Bilateral renal pelvis catheters were deployed per protocol in 7 patients. All patients had microhematuria; 2 had transient hematuria. In the per-protocol group, acute kidney injury developed in 1 patient with stage 4 chronic kidney disease. No patient suffered any other major adverse event. Serum creatinine concentration remained normal in 6 patients at 72 hours; and in 5 patients, estimated glomerular filtration rate had improved from baseline at 28 days. CONCLUSIONS: rNPT is feasible after cardiac surgery. If catheter placement protocol is strictly followed, it is associated with minimal patient risk and potential benefit. A controlled study (NCT07017933) is in progress to evaluate rNPT started before cardiopulmonary bypass and continued postoperatively. CLINICALTRIALSGOV IDENTIFIER: NCT05990660.