The population of patients with, or at risk for, concomitant kidney and heart disease, often termed “cardiorenal” disease, is large and continues to grow. Numerous studies have documented excess mortality risk and significant morbidity in this patient subpopulation (1,2). The interaction of kidney and heart disease leads to unique pathophysiology, disease manifestations, and treatment, necessitating specialized care that may not be addressed adequately by either cardiology or nephrology alone (3). Further, recent advances in kidney and cardiovascular technologies and devices have made the care of these patients increasingly complex (4,5). Together, there is a pressing, unmet need to develop specialized models of care for patients with combined kidney and heart disease (6,7).
In response, the University of Washington (UW) launched the Kidney-Heart Service in August 2020. The UW is a large academic medical center in Seattle, WA, which serves as a catchment area for persons in a five-state region (Washington, Wyoming, Alaska, Montana, and Idaho). The UW Kidney-Heart Service functions as a specialized, inpatient consultation service, staffed by three dedicated nephrologists, based at the UW System’s quaternary care university hospital, the UW Medical Center (UWMC). UWMC is the primary site for care of the most complex intensive cardiology care, including heart transplantation, cardiac device implantation, and cardiothoracic surgery. In this study, we present the clinical, education, and scholarship missions of this new service and 1-year outcomes.
Clinical Mission and Outcomes
The clinical mission of the UW Kidney-Heart Service is to provide exceptional, coordinated, multidisciplinary care for patients hospitalized with concomitant kidney and heart disease, thereby improving patient outcomes and optimizing utilization of resources. To achieve this goal, the service has prioritized consultation for patients admitted to cardiology or cardiothoracic services, or intensive care unit teams.
In just the first year, we have launched several key clinical initiatives. We have developed effective and streamlined communication strategies between the UW Kidney-Heart Service and Cardiology/Cardiothoracic Surgery Inpatient Services. All attendings on the UW Kidney-Heart Service have trained in point-of-care ultrasound, and have incorporated this practice into routine clinical decision making. In collaboration with our cardiology colleagues, we also have revised, updated, and promoted wider use of their evidence-based diuretic algorithm, which was developed to improve diuretic efficacy, reduce rates of diuretic resistance, decrease the risk of AKI and need for dialysis, and reduce length of stay (Supplemental Figure 1). This updated algorithm expands objective measures of diuretic efficacy to include assessment of urinary sodium excretion, expands its stepped approach to intensifying diuretics, and targets the selection of adjuvant diuretics on the basis of serum electrolyte and albumin levels. The updated algorithm also incorporates the use of novel approaches to volume management, such as hypertonic saline.
Although early, the initial results of these clinical initiatives are promising. Admissions and readmissions for acute decompensated heart failure are among the most common causes for hospitalizations in the United States; therefore, reducing frequency and improving outcomes associated with heart failure hospitalizations is a public health priority (8,9). AKI frequently complicates these hospitalizations and is associated with poor clinical outcomes and higher resource utilization (10). Between August 2020 and July 2021, approximately 44% of all patients hospitalized at UWMC with heart failure, and 82% of patients admitted to intensive care with heart failure, had AKI. Before the launch of the Kidney-Heart Service, and consistent with published data, patients admitted to UWMC with heart failure who developed AKI had three times the length of stay, a 3–4 higher rate of in-hospital death, and significantly higher rates of readmission within 30 days, as compared with patients with heart failure without AKI (Table 1). In the first 12-month period since the launch of the UW Kidney-Heart Service, a 3-day reduction in average length of stay in patients with heart failure and AKI was observed, compared with the previous 12-month period. Importantly, this reduction in length of stay did not lead to an increase in 30-day readmission rates. There was also a modest decline in the rates of inpatient acute dialysis in the 12 months after launch of the UW Kidney-Heart Service. We did observe a modest increase in hospital death rate; the reason for this is unclear and may be related to the coronavirus disease 2019 pandemic, or to possibly greater overall illness severity among patients hospitalized during this period. By contrast, there were no significant changes in length of stay, readmission rate, or death rate in patients with heart failure without AKI (Table 1). Although encouraging, these early preliminary data need to be verified over a longer period after the launch of the UW Kidney-Heart Service, and in the post coronavirus disease era.
1-year outcomes before (pre) and after (post) launch of the UW Kidney-Heart Service in patients hospitalized with heart failure, stratified by the presence or absence of concomitant AKI
Educational Mission and Outcomes
The educational mission of the UW Kidney-Heart Service is to provide educational opportunities for specialized training in the care of patients with kidney and heart disease. To fulfill this mission, we developed a specialized curriculum that includes core topics, such as volume and hemodynamic assessment, physiology of diuretic resistance, diuretic pharmacokinetics and management, cardiorenal physiology, kidney disease in patients with durable and nondurable mechanical circulatory support, electrolyte disorders, and acid-base disorders. We also introduced core cardiorenal lectures to the nephrology fellow Accreditation Council for Graduate Medical Education didactic series. Finally, both nephrology and cardiology fellows rotate on the service, allowing for crossdisciplinary training.
Scholarship Mission and Outcomes
The scholarship mission of the UW Kidney-Heart Service is to build a foundation to advance quality improvement and research in cardiorenal diseases. We have made several important strides to achieve this mission. First, we are collecting longitudinal electronic medical record data on patients seen by the Kidney-Heart Service, and tracking their in-hospital outcomes. Second, patients seen by the service are recruited directly into several research studies. For example, we have recently received funding for a National Institutes of Health R01 “Kidney Injury in Patients with Acute Decompensated Heart Failure” and a National Institutes of Health Administrative Supplement to study bioethical issues in patients admitted with acute decompensated heart failure and acute kidney injury (principal investigator: Bansal). We believe the UW Kidney-Heart Service will continue to inspire and support scholarship to advance care of patients with kidney and heart disease.
In summary, the UW Kidney-Heart Service is an innovative model to advance clinical care, education, and scholarship in cardiorenal disease. With the increasing complexity of disease and therapeutic options, integrated and subspecialty nephrology care models should be considered at other institutions across the United States.
Disclosures
D. Mariuma reports having an ownership interest in Amazon. J. A. Jefferson reports receiving research funding from Novartis; and reports receiving honoraria from Uptodate. N. Bansal reports having an advisory or leadership role as Kidney360 Associate Editor. All remaining authors have nothing to disclose.
Funding
None.
Acknowledgments
The content of this article reflects the personal experience and views of the author(s) and should not be considered medical advice or recommendation. The content does not reflect the views or opinions of the American Society of Nephrology (ASN) or Kidney360. Responsibility for the information and views expressed herein lies entirely with the author(s).
Author Contributions
N. Bansal and S. Shankland conceptualized the study; N. Arora, N. Bansal, J. Jefferson, D. Mariuma, K. O'Brien, and S. Shankland were responsible for the data curation; N. Bansal and S. Shankland were responsible for the formal analysis, the investigation, the methodology, and wrote the original draft; N. Bansal was responsible for the project administration; N. Arora, N. Bansal, J. Jefferson, D. Mariuma, K. O'Brien, and S. Shankland reviewed and edited the manuscript.
Supplemental Material
This article contains supplemental material online at http://kidney360.asnjournals.org/lookup/suppl/doi:10.34067/KID.0000602022/-/DCSupplemental.
Supplemental Figure 1. UW HEART FAILURE IV Diuretic Protocol.
Footnotes
This article contains a podcast at https://www.asn-online.org/media/podcast/K360/2022_04_28_KID0000602022.mp3.
- Received January 19, 2022.
- Accepted January 25, 2022.
- Copyright © 2022 by the American Society of Nephrology
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