Nephrologists Rather Than Intensivists Should Manage Kidney Replacement Therapy in the ICU: PRO

Who should manage RRT in the ICU? The answer to this question is straightforward: it should of course be the nephrologist—that’s what we do. Frankly, we wonder why this is even a subject for debate. As nephrology consultants, we are expected to provide expert advice throughout the hospital for patients with AKI and for those with ESKD who are hospitalized. We are warmly welcomed on surgical and medical wards, where our comprehensive consultation and dialysis management plans are appreciated and accepted. This is a tacit acknowledgment of the obvious fact that we as nephrologists are immersed in the delivery of RRT from the day we commence specialty training and thus are optimally positioned to prescribe and manage all forms of RRT in the sickest hospitalized patients. However, our role in RRT delivery is challenged in some ICUs where intensivist colleagues, accustomed to managing other compromised organ systems, argue that they are sufficiently adept at managing failed kidneys. If intensivists are the undisputed stewards of mechanical ventilation and vasopressors, why, they argue, should this not extend to RRT? We believe that this thinking is fundamentally flawed.

The debate over control of RRT can be traced to the advent of continuous RRT in the late 1970s.¹ In a pair of publications published more than 25 years ago in Seminars in Dialysis, Emil Paganini, one of the innovators of continuous RRT, made the case for nephrology control, arguing that it is the nephrologist who truly understands the intricacies of extracorporeal kidney support.² David Bihari, an intensivist, argued that critically ill patients with multisystem organ failure require management by a specialist who is responsible for the overall management of the patient and who remains present in the ICU over time rather than merely rounding episodically.³ This clash of views persists to the present day, and the fundamental arguments on each side remain essentially unchanged.

Careful analysis suggests that this debate is actually rooted in more foundational issues regarding the role of nephrologists in the ICU. What are the perceived and actual added values that we as nephrologists bring to the care of the critically ill patient with AKI? Are we merely providing a technical or procedural service, or do we provide broader expertise? If it is the former, a strong argument can be made for our replaceability by non-nephrologist colleagues who have acquired skills in RRT delivery.

Our management of critically ill patients with severe AKI is much broader than simply considerations pertaining to the initiation and delivery of RRT. Nephrologists bring an understanding of the broad spectrum of potential AKI etiologies and the ability to recognize less common causes of ICU-associated AKI such as renal vasculitis, acute glomerulonephritis, and paraprotein-associated disease, which also have unique therapeutic considerations. As nephrologists, a key part of our expertise is to be attentive to issues related to drug dosing and early management of the electrolyte and acid-base disorders that accompany AKI, which, when managed promptly and effectively, can potentially avoid the need for emergent RRT. However, there is a perception that we often focus on minutiae of care that are peripheral to the urgent management needs of the critically ill patient and that our rote recommendations pertaining to volume resuscitation, avoidance of hypotension, and discontinuation of nephrotoxins are unhelpful. If we wish to be consulted early in the course of AKI, we need to ensure that our input is substantive, thoughtful, and pragmatic.

Whereas RRT is a component of the curriculum in most critical care training programs, it is a central part of nephrology training and continuing education. Moreover, caring for patients requiring maintenance dialysis is a major part of most nephrologists’ clinical practice. Adapting this expertise to the ICU is a natural extension of the nephrologist’s skill set. We have a deep understanding of the theoretical foundations of hemodialysis and hemofiltration, the management of extracorporeal circuits and their complications, the hemodynamic stresses of RRT, management of vascular access, and the implications of RRT on medication dosing.⁴ As nephrologists, we are also able to prescribe and troubleshoot a full spectrum of RRT modalities, including peritoneal dialysis. For patients who leave the ICU with persistent RRT dependence, it is the nephrologist who will provide follow-up on the ward and, if necessary, the outpatient setting, not the intensivist. Patients who recover to RRT independence may still be left with significant post-AKI kidney impairment and will benefit from specialized nephrology follow-up after hospital discharge.⁵ In all of these scenarios, initiating a relationship with the patient in the ICU ensures optimal continuity of care.

In addition to patients with AKI, a substantial proportion of patients receiving RRT in the ICU have ESKD. Nephrologists are best positioned to understand the subtleties of their kidney disease and are the right people to tailor their usual dialysis prescription to the ICU setting. When patients are admitted to ICUs at medical centers affiliated with their dialysis program, they get the further benefit of care from nephrologists with whom they already have an established relationship.

Management of RRT in the ICU should not be viewed as a nephrologist’s natural entitlement. Acknowledging the dynamic clinical needs of critically ill patients, especially those receiving RRT who are frequently among the sickest in the ICU, nephrologists must maintain a presence in the ICU and not be perceived as mere itinerant purveyors of RRT. It is the responsibility of the consulting nephrologist to keep abreast of patient’s evolving clinical issues and new diagnostic studies because these may significantly affect the RRT prescription. If we expect to direct RRT management in the ICU setting, we must maintain our expertise across the full range of critical care nephrology and be up to date on advances in general ICU care.⁶ Although some nephrologists may choose to pursue additional training in critical care, this should not be a prerequisite for management of RRT in the ICU.⁷

Although all aspects of RRT management should be led by the consulting nephrologist, the management of all RRT in the critically ill patient must be coordinated with the broader management of the patient by the ICU team. From experience, the most common areas of dispute between nephrology and critical care services relate to specific indications for initiation of RRT and volume management once treatment is started. Although discussions around the timing of initiation were previously often a matter of passionately held opinion, recent clinical trials have provided evidence that preemptive initiation of RRT before the development of pulmonary edema, hyperkalemia, or severe metabolic acidosis unresponsive to medical management does not result in improved outcomes compared with a strategy of active medical management and moderately delayed initiation of RRT in those without kidney recovery.^8–10 Discussions regarding the optimal timing of RRT initiation can now be tempered by this rigorous evidence, combined with assessment of the patient’s goals of care. The management of net ultrafiltration during RRT must also be aligned with the overall goals for the patient’s management and continuously reassessed as the patient’s status evolves. This may involve a strategy of joint management, with the critical care team empowered to adjust ultrafiltration rates independently within prespecified parameters as the patient’s volume management progresses from resuscitation through maintenance and then to deresuscitation. Regularly scheduled joint ICU/nephrology “bullet rounds” can enhance communication and ensure that RRT is being delivered in a manner that reflects the objectives that were determined by all the key players in the patient’s care.

Nephrologists should be managing the delivery of RRT patients in the ICU, as is the case in all other inpatient and ambulatory settings. This is supported by the undebatable premise that the healthcare provider with the best training and most extensive clinical experience should direct the management of a given problem. There is no doubt that many ICU specialists are familiar with acute RRT and can competently deploy RRT in their units. But familiarity and expertise should not be conflated. Expertise in all aspects of RRT delivery is a core competency of nephrologists and a major focus of what we do as kidney specialists. By bringing these skills to the ICU, patient care is invariably enhanced. However, to establish and maintain credibility in the ICU, it is incumbent on nephrologists to be deeply invested in the care of critically ill patients and demonstrate why our contributions are truly valuable. Close collaboration with our ICU counterparts regarding all aspects of RRT delivery will ensure coordinated care of the highest quality.

Disclosures

P.M. Palevsky reports consultancy for Janssen Research & Development, LLC; is president, a member, and on the scientific advisory board of the National Kidney Foundation; is a member and on the Quality, Safety and Accountability Committee of the Renal Physicians Association; is chair and on the medical review board of Quality Insights Renal Network 4; is section editor of Renal Failure for UpToDate; and is a member on the editorial board of the Journal of Intensive Care Medicine. R. Wald reports research funding from Baxter; is on the editorial board of the Clinical Journal of the American Society of Nephrology, Kidney Medicine, and Kidney360; and is a contributor for UpToDate.

Funding

None.

Author Contributions

P.M. Palevsky was responsible for conceptualization and wrote the original draft of the manuscript; and both authors reviewed and edited the manuscript.