Evaluation of the Efficacy of Recombinant Human Brain Natriuretic Peptide in Patients With Diuretic Resistance After Cardiac Surgery: a Prospective Single-center Single-blind Randomized Controlled Study

Postoperative adult patients (aged ≥18 years) with fluid overload were randomly assigned to groups, divided into the rhBNP group and the control group. The control group received positive inotropic agents, increased mean arterial pressure, restricted fluid intake, and increased the dosage of diuretics. The rhBNP group received conventional treatment in addition to a loading dose of 1.5-2 μg/kg intravenously, according to the instructions, to maintain a dosage of 0.0075-0.01 μg/kg/min continuously infused via intravenous pump for 72 hours, with dosage adjusted based on blood pressure. The grouping of subjects was concealed, and researchers were not allowed to access grouping information before the analysis was completed, with early unblinding prohibited. The primary research endpoint was the incidence of renal replacement therapy. Secondary research endpoints included the duration of tracheal intubation after cardiac surgery, CICU time after cardiac surgery, and length of hospitalization after cardiac surgery. Blood and urine samples were collected at the time of enrollment, 1 hour after maintaining the rhBNP dosage of 0.0075-0.01 μg/kg/min, and at 24 hours, 48 hours, and 72 hours after medication administration.