Outcome among patients with acute renal failure needing continuous renal replacement therapy: A single center study

The landscape of renal replacement therapy in Veterans Affairs Medical Center intensive care units

Background

Outpatient dialysis is standardized with several evidence-based measures of adequacy and quality that providers aim to meet while providing treatment. By contrast, in the intensive care unit (ICU) there are different types of prolonged and continuous renal replacement therapies (PIRRT and CRRT, respectively) with varied strategies for addressing patient care and a dearth of nationally accepted quality parameters. To eventually describe appropriate quality measures for ICU-related renal replacement therapy (RRT), we first aimed to capture the variety and prevalence of basic strategies and equipment utilized in the ICUs of Veteran Affairs (VA) medical facilities with inpatient hemodialysis capabilities.

Methods

Via email to the dialysis directors of all VA facilities that provided inpatient hemodialysis during 2018, we requested survey participation regarding aspects of RRT in VA ICUs. Questions centered around the mode of therapy, equipment, solutions, prescription authority, nursing, anticoagulation, antimicrobial dosing, and access.

Results

Seventy-six centers completed the questionnaire, achieving a response rate of 87.4%. Fifty-five centers reported using PIRRT or CRRT in addition to intermittent hemodialysis. Of these centers, 42 reported being specifically CRRT-capable. Over half of respondents had the capabilities to perform PIRRT. Twelve centers (21.8%) were equipped to use slow low efficient dialysis (SLED) alone. Therapy was largely prescribed by nephrologists (94.4% of centers).

Conclusions

Within the VA system, ICU-related RRT practice is quite varied. Variation in processes of care, prescription authority, nursing care coordination, medication management, and safety practices present opportunities for developing cross-cutting measures of quality of intensive care RRT that are agnostic of modality choice.

[Interactions between lung and kidney in the critically ill]

Interactions between lung and kidney can significantly affect the course of acute diseases, a phenomenon that was first observed in the 1950s by describing pulmonary dysfunction in uremic patients. From animal experiments there is ample evidence for remote lung injury following acute kidney injury (AKI), with an increased risk for the development of pulmonary edema and acute respiratory distress syndrome (ARDS). Coincident ARDS and AKI are associated with higher rates of intubation and mechanical ventilation, significantly prolonged weaning from mechanical ventilation and increased mortality. On the other hand, acute lung diseases and mechanical ventilation can promote the development of AKI and are associated with increased mortality when AKI is also present. These bidirectional interactions may include hemodynamic adverse effects during mechanical ventilation or volume overload as well as the release or decreased clearance and metabolism of proinflammatory mediators (e.g., interleukin-6 and tumor necrosis factor-α), which may induce and aggravate distant organ injury. The aim of this work is to examine the interactions between lung and the kidney in critically ill patients, as well as discuss potential preventive approaches.

The systemic nature of CKD

The accurate definition and staging of chronic kidney disease (CKD) is one of the major achievements of modern nephrology. Intensive research is now being undertaken to unravel the risk factors and pathophysiologic underpinnings of this disease. In particular, the relationships between the kidney and other organs have been comprehensively investigated in experimental and clinical studies in the last two decades. Owing to technological and analytical limitations, these links have been studied with a reductionist approach focusing on two organs at a time, such as the heart and the kidney or the bone and the kidney. Here, we discuss studies that highlight the complex and systemic nature of CKD. Energy balance, innate immunity and neuroendocrine signalling are highly integrated biological phenomena. The diseased kidney disrupts such integration and generates a high-risk phenotype with a clinical profile encompassing inflammation, protein-energy wasting, altered function of the autonomic and central nervous systems and cardiopulmonary, vascular and bone diseases. A systems biology approach to CKD using omics techniques will hopefully enable in-depth study of the pathophysiology of this systemic disease, and has the potential to unravel critical pathways that can be targeted for CKD prevention and therapy.

Early mortality on continuous renal replacement therapy (CRRT): the prairie CRRT study

Background

Patients with acute kidney injury (AKI) requiring renal replacement therapy (RRT) have an increased short-term and long-term risk of mortality. In most North American intensive care units (ICUs), these patients receive continuous renal replacement therapy (CRRT).

Objective

We aim to identify clinical and demographic factors associated with mortality within 24 h of initiating CRRT.

Design

This paper is a prospective cohort study.

Setting

The setting involves three ICUs (12-bed surgical ICU, 10-bed medical ICU, and a 7-bed combined ICU for both medical and surgical patients) of the Regina Qu’Appelle Health Region (RQHR) Saskatchewan, Canada.

Patients

The patients were 106 individuals with AKI who were admitted to the ICUs and received CRRT from April 2013 to September 2014.

Measurements

Date and time of admission, transfer to, and initiation of CRRT were documented. Demographic data, use of vasoactive medications, ventilator settings, pH, urine output, and chronic disease comorbidities were measured.

Methods

The methods involved a stepwise multiple variable logistic regression model using death within 24 h of starting CRRT as the dependent variable, with significant variables derived from univariate analysis as covariates.

Results

Of the 2634 patients admitted to the ICUs in the study period (April 2013 to September 2014), 83.6 % (2201/2634) had no AKI. Two hundred and sixty-nine or 10.2 % of the patients had stage 3 AKI. One hundred six of the 269 patients (40%) were started on CRRT. Of those on CRRT, 66/106 died in the ICU while on CRRT. Seventeen of the 66 patients (26%) died within 24 h of initiating therapy. In univariate logistic regression models, factors associated with early mortality included fraction of inspired oxygen (per 0.1 unit) (OR 1.39, 95 % CI 1.09–1.77); epinephrine dose >10 μg/min (OR 5.81, 95 % CI 1.86–18.16); vasopressin >0.02 μg/min (OR 3.99, 95 % CI 1.07–14.84); and norepinephrine dose >20 μg/min (OR 11.04, 95 % CI 2.38–51.24) which were associated with early mortality. When included in stepwise multivariate logistic regression analysis, only FiO₂ (per 0.1 unit) and the dose of norepinephrine of >20 μg/min were independently associated with early mortality.

Limitations

The small sample size was a limitation of this study.

Conclusion

Patients admitted to the ICU with AKI requiring CRRT have a high risk of early mortality. In these patients, vasopressor use and hypoxia were independently associated with adverse short-term survival.

Proteomic analisys of protein extraction during hemofiltration with on-line endogenous reinfusion (HFR) using different polysulphone membranes

In end-stage renal disease patients, extracorporeal dialytic therapy is not able to prevent the accumulation of toxins related to the uremic syndrome, a severe complication that increases morbidity and mortality rate. In this paper, hemoFiltration with on-line Reinfusion (HFR) architecture is used to evaluate the effect of a more permeable membrane on the extraction of medium-high molecular weight molecules. The aim of this study was to compare two polysulphone membranes for convective chamber: polyphenylene High Flux (pHF) and polyphenylene Super High-Flux (pSHF). Fourteen patients were subjected to HFR with pHF and pSHF membranes and ultra filtrate (UF) samples were collected to evaluate molecular weight cut-off (MWCO) and to identify extracted proteins. Furthermore, image analysis software was used in order to evaluate change in protein extraction during the dialysis. The quantification of four proteins by immunoassay demonstrates a higher permeability of pSHF membrane. Two-dimensional electrophoresis (2-DE) gels showed, for both membranes, the greater number of protein spots at 235 min. Some of the identified proteins, involved in nephropathic disease complications, were compared to assess differences in extraction during dialytic treatment by PDQuest analysis. UF proteomic analysis demonstrated a different behavior for the two membranes; pHF membrane was more permeable at the beginning of HFR treatment (15 min), while pSHF membrane at the end of treatment (235 min). Proteomic analysis is a suitable approach to investigate the behavior of different membranes during dialysis. Results indicated that pSHF membrane offers the higher permeability, and showed higher efficiency in removal of middle molecules related to uremic syndrome.

Renal consequences of parenteral nutrition

Parenteral nutrition (PN) can be described as the "Intravenous administration of nutrients necessary to sustain life in those who would otherwise have died or suffered serious disease". PN is indicated in children who cannot be fully fed by the oral or intestinal route, usually as a result of intestinal failure. Intradialytic parenteral nutrition (IDPN) is rarely indicated in children on dialysis and does not confer a benefit over enteral supplements in the compliant patient with adequate intestinal function. Renal and metabolic consequences of PN are potentially life-threatening and include disorders of glucose homeostasis, acid-base and fluid and electrolyte disturbances, nephrolithiasis, impaired renal function and metabolic bone disease. Many of these complications are avoidable. Adequate clinical and biochemical assessment and monitoring of children receiving PN by a multidisciplinary nutrition support team is recommended to mitigate against the risks of these complications.

Choice of renal replacement therapy modality and dialysis dependence after acute kidney injury: a systematic review and meta-analysis

PURPOSE

Choice of renal replacement therapy (RRT) modality may affect renal recovery after acute kidney injury (AKI). We sought to compare the rate of dialysis dependence among severe AKI survivors according to the choice of initial renal replacement therapy (RRT) modality applied [continuous (CRRT) or intermittent (IRRT)].

METHODS

Systematic searches of peer-reviewed publications in MEDLINE and EMBASE were performed (last update July 2012). All studies published after 2000 reporting dialysis dependence among survivors from severe AKI requiring RRT were included. Data on follow-up duration, sex, age, chronic kidney disease, illness severity score, vasopressors, and mechanical ventilation were extracted when available. Results were pooled using a random-effects model.

RESULTS

We identified 23 studies: seven randomized controlled trials (RCTs) and 16 observational studies involving 472 and 3,499 survivors, respectively. Pooled analyses of RCTs showed no difference in the rate of dialysis dependence among survivors (relative risk, RR 1.15 [95 % confidence interval (CI) 0.78-1.68], I(2) = 0 %). However, pooled analyses of observational studies suggested a higher rate of dialysis dependence among survivors who initially received IRRT as compared with CRRT (RR 1.99 [95 % CI 1.53-2.59], I (2) = 42 %). These findings were consistent with adjusted analyses (performed in 7/16 studies), which found a higher rate of dialysis dependence in IRRT-treated patients [odds ratio (OR) 2.2-25 (5 studies)] or no difference (2 studies).

CONCLUSIONS

Among AKI survivors, initial treatment with IRRT might be associated with higher rates of dialysis dependence than CRRT. However, this finding largely relies on data from observational trials, potentially subject to allocation bias, hence further high-quality studies are necessary.

Outcomes of patients with end-stage renal disease (ESRD) under chronic hemodialysis requiring continuous renal replacement therapy (CRRT) and patients without ESRD in acute kidney injury requiring CRRT: a single-center study

In most continuous renal replacement therapy (CRRT) studies, end-stage renal disease (ESRD) patients were excluded and the outcomes of patients with ESRD treated with chronic hemodialysis (HD) were unknown. The purposes of this study were to (1) evaluate short-term patient survival and (2) compare the survival of conventional HD patients needing CRRT with the survival of non-ESRD patients in acute kidney injury (AKI) requiring CRRT. We evaluated adults (>18 years) requiring CRRT who were treated in the intensive care unit (ICU) at Kosin University Gospel Hospital from January 1, 2009 to December 31, 2010. A total of 100 (24 ESRD, 76 non-ESRD) patients underwent CRRT during the study period. Patients were divided into two major groups: patients with ESRD requiring chronic dialysis and patients without ESRD (non-ESRD) with AKI. We compared the survival of conventional HD patients requiring CRRT with the survival of non-ESRD patients in AKI requiring CRRT. For non-ESRD patients, the 90-day survival rate was 41.6%. For ESRD patients, the 90-day survival rate was 55.3%. Multivariate Cox proportional hazards analyses demonstrated that conventional HD was not a significant predictor of mortality (hazard ratio [HR]: 0.334, 95% confidence interval [CI]: 0.063-1.763, P = 0.196), after adjustment for age, gender, presence of sepsis, APACHE score, use of vasoactive drugs, number of organ failures, ultrafiltration rate, and arterial pH. The survival rates of non-ESRD and ESRD patients requiring CRRT did not differ; ESRD with conventional HD patients may be not a significant predictor of mortality.

In critically ill patients requiring CRRT, AKI is associated with increased respiratory failure and death versus ESRD

BACKGROUND/AIMS

To compare outcomes of critically ill patients with acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT) versus those with pre-existing end-stage renal disease (ESRD) requiring CRRT to identify factors that contribute to the increased mortality seen in AKI patients.

METHODS

Retrospective cohort of 257 intensive care unit (ICU) patients who received CRRT. AKI is defined as requiring CRRT with an admission serum creatinine ≤1 mg/dL; ESRD is defined as chronic dialysis dependence. Primary outcome was hospital mortality. Multivariate logistic regression was performed to determine the impact of APACHE II score, intubation, vasopressors, infection, diabetes, hypertension, gender, and race on mortality.

RESULTS

Of 257 patients requiring CRRT, 28 had ESRD and 108 had AKI. Hospital mortality was higher in patients with AKI versus ESRD (69% vs. 39%, p = 0.0032). Severity of illness using APACHE II was similar in AKI and ESRD. Patients with AKI were more likely to require mechanical ventilation (89% vs. 57%, p = 0.0003). After multivariate analysis, the requirement for mechanical ventilation was the single factor associated with increased hospital mortality [odds ratio (OR): 3.1].

CONCLUSIONS

In ICU patients requiring CRRT, patients with AKI have a higher mortality than patients with ESRD due to an increased need for mechanical ventilation.

Acute renal failure requiring renal replacement therapy in the intensive care unit: impact on prognostic assessment for shared decision making

A 69-year-old female was receiving renal replacement therapy (RRT) for acute renal failure (ARF) in an intensive care unit (ICU). Consultation was requested from the palliative medicine service to facilitate a shared decision-making process regarding goals of care. Clinician responsibility in shared decision making includes the formulation and expression of a prognostic assessment providing the necessary perspective for a spokesperson to match patient values with treatment options. For this patient, ARF requiring RRT in the ICU was used as a focal point for preparing a prognostic assessment. A prognostic assessment should include the outcomes of most importance to a discussion of goals of care: mortality risk and survivor functional status, in this case including renal recovery. A systematic review of the literature was conducted to document published data regarding these outcomes for adult patients receiving RRT for ARF in the ICU. Forty-one studies met the inclusion criteria. The combined mean values for short-term mortality, long-term mortality, renal-function recovery of short-term survivors, and renal-function recovery of long-term survivors were 51.7%, 68.6%, 82.0%, and 88.4%, respectively. This case example illustrates a process for formulating and expressing a prognostic assessment for an ICU patient requiring RRT for ARF. Data from the literature review provide baseline information that requires adjustment to reflect specific patient circumstances. The nature of the acute primary process, comorbidities, and severity of illness are key modifiers. Finally, the prognostic assessment is expressed during a family meeting using recommended principles of communication.