Prolonged Intermittent Kidney Replacement Therapy

Abstract

Kidney replacement therapy (KRT) is a vital, supportive treatment for patients with critical illness and severe AKI. The optimal timing, dose, and modality of KRT have been studied extensively, but gaps in knowledge remain. With respect to modalities, continuous KRT and intermittent hemodialysis are well-established options, but prolonged intermittent KRT is becoming more prevalent worldwide, particularly in emerging countries. Compared with continuous KRT, prolonged intermittent KRT offers similar hemodynamic stability and overall cost savings, and its intermittent nature allows patients time off therapy for mobilization and procedures. When compared with intermittent hemodialysis, prolonged intermittent KRT offers more hemodynamic stability, particularly in patients who remain highly vulnerable to hypotension from aggressive ultrafiltration over a shorter duration of treatment. The prescription of prolonged intermittent KRT can be tailored to patients’ progression in their recovery from critical illness, and the frequency, flow rates, and duration of treatment can be modified to avert hemodynamic instability during de-escalation of care. Dosing of prolonged intermittent KRT can be extrapolated from urea kinetics used to calculate clearance for continuous KRT and intermittent hemodialysis. Practice variations across institutions with respect to terminology, prescription, and dosing of prolonged intermittent KRT create significant challenges, especially in creating specific drug dosing recommendations during prolonged intermittent KRT. During the coronavirus disease 2019 pandemic, prolonged intermittent KRT was rapidly implemented to meet the KRT demands during patient surges in some of the medical centers overwhelmed by sheer volume of patients with AKI. Ideally, implementation of prolonged intermittent KRT at any institution should be conducted in a timely manner, with judicious planning and collaboration among nephrology, critical care, dialysis and intensive care nursing, and pharmacy leadership. Future analyses and clinical trials with respect to prescription and delivery of prolonged intermittent KRT and clinical outcomes will help to guide standardization of practice.

Switching from continuous veno‐venous hemodiafiltration to intermittent sustained low‐efficiency daily hemodiafiltration (SLED‐f) in pediatric acute kidney injury: A prospective cohort study

“…It is important to take into consideration that our patients have already undergone CKRT prior to undergoing SLED‐ f and thus the Kt/V calculated for SLED‐ f is lower. As per Levine et al, a spKtV of 0.7–0.9 equivalent to a weekly standard Kt/V of approximately 2.5–4 (treatment frequency is 5–7 times a week) ensures PIKRT dosing that is approximately midway between recommended doses for CKRT and intermittent hemodialysis 20 . Although there are no pediatric studies on solute removal during PIKRT, several adult studies indicate that the adequacy of small solute clearance in SLED is comparable, if not greater than that of CKRT 41,42 .…”

Debate: Intermittent Hemodialysis versus Continuous Kidney Replacement Therapy in the Critically Ill Patient: The Argument for CKRT

“…Limitations to PIKRT/SLED include limited evidence about medication dosing and monitoring (e.g., antimicrobials), higher risk of electrolyte disorders (e.g., hypophosphatemia, hypokalemia), and added bedside workload. 101 So while there may be a reasonable rationale for the adoption of PIKRT/ SLED, its utilization for initiation, maintenance, and deescalation of KRT in critically ill patients remains limited and warrants further investigation. 9,51,82,104 In conclusion, the choice of KRT modality in the ICU should be driven by more pragmatism and less dogma.…”

“…, hypophosphatemia, hypokalemia), and added bedside workload. 101 So while there may be a reasonable rationale for the adoption of PIKRT/SLED, its utilization for initiation, maintenance, and de-escalation of KRT in critically ill patients remains limited and warrants further investigation. 9,51,82,104…”

“…There is clear recognition that the conventional intermittent HD prescription is inadequate for many critically ill patients and, as such, has provoked interest in prolonged intermittent KRT (PIKRT). 87,101 PIKRT, also commonly referred to as sustained low-efficiency dialysis (SLED), is modified intermittent HD characterized by slower blood flow rates and more prolonged durations (e.g., 8-12 hours) than conventional intermittent HD (e.g., 3-4 hours). Compared with conventional intermittent HD, SLED is associated with improved hemodynamic profile.…”

“…96,103 Prescription varies across centers with respect to duration, frequency, and other treatment parameters (e.g., blood flow rate, dialysate flow rate, filter type, and modes of solute clearance) (Figure 3). 101 As such, there is no standardized approach to PIKRT/SLED delivery, and certain complexities should be considered. Limitations to PIKRT/SLED include limited evidence about medication dosing and monitoring (e.g., antimicrobials), higher risk of electrolyte disorders (e.g., hypophosphatemia, hypokalemia), and added bedside workload.…”