Outcomes of Concentrated Furosemide Infusions on Postoperative Atrial Fibrillation Rates in Kidney Transplant Recipients

Introduction Postoperative atrial fibrillation is an arrhythmia that may complicate postsurgical care in kidney transplant recipients and is associated with longer hospitalizations, postsurgical complications, and increased in-hospital mortality. Pathophysiology is not well understood but is thought to be multifactorial. Iatrogenic hypervolemia may contribute to the incidence of postoperative atrial fibrillation. Project Aims The program evaluation aim was to evaluate the effects of furosemide concentration on reducing volume overload, and subsequently postoperative atrial fibrillation incidence. Design This was a single-center, retrospective, cohort study that analyzed kidney transplant recipients during index hospitalization. Recipients receiving furosemide infusions of 500 mg/50 mL between June 2022 and May 2023 were considered the concentrated group and recipients receiving infusions of 500 mg/250 mL between January 2013 and December 2017 were the dilute group. Results There was no difference identified in atrial fibrillation rates when using concentrated versus dilute furosemide infusions (7.7% vs 12.4%; P = .101). When excluding those with immediate graft function, there was a lower incidence in the concentrated group (9.3% vs 22.0%, P = .031) compared to slow/delayed graft function. Recipients in the concentrated infusion group had higher rates of high (11.7% vs 35.1%) and very high (3.0% vs 14.9%) cardiovascular risk ( P < .001). Recipients receiving concentrated infusions had improvement in net fluid balance (0.4 L vs 1.4 L; P < .001) with higher furosemide exposure (2.3 g vs 1.4 g; P < .001). Conclusions Postoperative atrial fibrillation rates were similar between groups, Recipients with slow/delayed graft function had lower rates of postoperative atrial fibrillation with concentrated furosemide.