Emergency Potassium Normalization Treatment Including Sodium Zirconium Cyclosilicate: A Phase II, Randomized, Double-blind, Placebo-controlled Study (ENERGIZE)

Heart Failure and Edema Costs in Patiromer and Sodium Zirconium Cyclosilicate Users

Key Points

Prior research suggests differences in rates of heart failure hospitalization or serious emergency department visits between patients on patiromer versus sodium zirconium cyclosilicate. Total costs of heart failure–related hospitalizations and emergency department visits may be lower in patients on patiromer compared with sodium zirconium cyclosilicate.

Background

Previous work suggested differences between patients taking patiromer or sodium zirconium cyclosilicate (SZC) in real-world risk of heart failure (HF) hospitalizations and edema hospitalizations or emergency department (ED) visits (edema events). We further investigated these differences to assess economic importance. Retrospective study using published event rates and mean costs derived from Optum's deidentified Clinformatics Data Mart Database.

Methods

We designed a model to estimate adjusted economic offsets that combined respective patiromer and SZC HF hospitalization (25.1 and 35.8; difference 10.7 [95% confidence interval (CI)2, 2.6 to 18.8]) and edema event (3.4 and 7.1; difference 3.6 [95% CI, 1.7 to 7.1]) rates/100 person-years from the original published work with costs from our parallel data extract spanning 2019–2021, adjusted to 2021 US dollars.

Results

In a base case of mean HF hospitalization, edema event, and 30-count potassium-binder prescription costs from our data extract, the estimated mean savings with patiromer was $1428 per person per year (95% CI, −$1508 to $4652). Respective costs per person per year for patiromer versus SZC were $8526 versus $12,622 (difference $4096 [95% CI, $116 to $7320]) for HF hospitalization and edema events, and $10,649 versus $7981 (difference −$2668) for potassium binders, totaling $19,175 for patiromer versus $20,603 for SZC.

Conclusions

With differing drug costs, hospitalization and ED costs offset this difference when event rates were numerically small. Model outcomes were driven by HF hospitalization cost and least influenced by edema ED visit cost. A limitation was that the Clinformatics Data Mart data extract may differ from the original work.

Effectiveness, safety, and treatment pattern of sodium zirconium cyclosilicate in Chinese patients with hyperkalemia: interim analysis from a multicenter, prospective, real-world study (Actualize Study)

Introduction: Sodium zirconium cyclosilicate (SZC) is a nonabsorbed cation-exchanger approved in China for the treatment of hyperkalemia [HK; serum potassium (sK+) levels >5.0 mmol/L]. This is the first real-world study aimed to assess the effectiveness, safety, and treatment patterns of SZC in Chinese patients with HK. Here we present the results of the first interim analysis. Methods: This multicenter, prospective, cohort study included patients aged ≥18 years with documented HK within 1-year before study enrollment day. These patients were followed up for 6 months from the enrollment day after initiating SZC treatment. The treatment was categorized into correction phase (FAS-P1) and maintenance phase (FAS-P2 new and ongoing users). Subgroup analysis was performed in patients on hemodialysis (FAS-H). The primary objective was evaluation of safety profile of SZC; secondary objectives included assessment of treatment patterns of SZC and its effectiveness. Results: Of 421 screened patients, 193, 354, and 162 patients were enrolled in the FAS-P1, FAS-P2, and FAS-H groups, respectively. sK+ levels were reduced significantly from 5.9 mmol/L to 5.0 mmol/L after the correction phase. For the maintenance phase, the mean sK+ levels were maintained at 5.2 mmol/L and 5.0 mmol/L in the FAS-P2 new and ongoing user, respectively, and 5.3 mmol/L in the FAS-H subgroup. A considerable proportion of patients showed normokalemia after 48 h of SZC treatment (FAS-P1:51.3%) which was maintained up to 6 months in the maintenance phase (FAS-P2:44%). SZC was well-tolerated. Conclusion: SZC was effective and safe for the treatment of HK in real-world clinical practice in China.

Comparison of Sodium Zirconium Cyclosilicate to Sodium Polystyrene Sulfonate in the Inpatient Management of Acute Hyperkalemia

Background: Oral potassium binders have a role in the management of acute hyperkalemia among hospitalized patients. However, with therapeutic additions to this class, there is insufficient evidence between potassium binders to support a standard of care recommendation for use in this acute setting. Objective: The purpose of this study was to compare the acute potassium lowering effects of sodium zirconium cyclosilicate (SZC) and sodium polystyrene sulfonate (SPS). Methods: A retrospective review of admitted patients who received SZC or SPS was conducted after exemption from the Institutional Review Board. Patients with baseline potassium values less than 5.1 mmol/L or factors contributing to potentially false report of serum potassium were excluded. The primary outcome was the average change in potassium from baseline to 24 hours following potassium binder administration. Secondary outcomes compared changes to potassium from baseline to various time periods after administration, presence of electrolyte changes, and documentation of serious adverse events. Results: A total of 246 patients were included, with 128 receiving SZC and 118 receiving SPS. Mean change in serum potassium (mmol/L) at 24 hours was not significant between binders (-.78 vs -.91; P = .22). Secondary efficacy and safety outcomes were also similar between groups. A total of 5 serious adverse events were reported, occurring only in the SPS group. Conclusion: SZC and SPS have comparable effects in acute potassium reduction, with serious gastrointestinal adverse events documented only in SPS patients. Health systems may consider this data in determining medication formularies or during order set development.

Cost-effectiveness of sodium zirconium cyclosilicate for advanced chronic kidney patients in Singapore

INTRODUCTION

Hyperkalaemia (HK) is prevalent among patients with chronic kidney disease (CKD) and chronic heart failure, especially if they are treated with renin-angiotensin-aldosterone system inhibitors (RAASi). This study evaluated the cost-effectiveness of a newly developed anti-HK therapy, sodium zirconium cyclosilicate (SZC), to the current standard of care for treating HK in advanced CKD patients from the Singapore health system perspective.

METHODS

We adapted a global microsimulation model to simulate individual patients' potassium level trajectories with baseline potassium ≥5.5 mmol/L, CKD progression, changes in treatment, and other fatal and non-fatal events. Effectiveness data was derived from ZS-004 and ZS-005 trials. Model parameters were localised using CKD patients' administrative and medical records at the Singapore General Hospital Department of Renal Medicine. We estimated the lifetime cost and quality-adjusted life years (QALYs) of each HK treatment, and the incremental cost-effectiveness ratio of SZC.

RESULTS

SZC demonstrated cost-effectiveness with an incremental cost-effectiveness ratsio of SGD 45 068 per QALY over a lifetime horizon, below the willingness-to-pay threshold of SGD 90 000 per QALY. Notably, SZC proved most cost-effective for patients with less severe CKD who were concurrently using RAASi. Sensitivity analyses confirmed the robustness of the findings, accounting for alternative parameter values and statistical uncertainty.

CONCLUSION

This study establishes the cost-effectiveness of SZC as a treatment for HK, highlighting its potential to mitigate the risk of hyperkalaemia and optimise RAASi therapy. These findings emphasise the value of integrating SZC into the Singapore health system for improved patient outcomes and resource allocation.

Comparative Efficacy of Sodium Zirconium Cyclosilicate and Sodium Polystyrene Sulfonate for Acute Hyperkalemia: A Retrospective Chart Review

Background: Sodium polystyrene sulfonate (SPS) is a nonselective sodium-potassium exchange resin commonly used along with intravenous (IV) insulin, albuterol, furosemide, and/or calcium for the treatment of acute hyperkalemia. Sodium zirconium cyclosilicate (SZC) is a newer non-absorbed exchange resin that preferentially increases fecal potassium excretion from the gastrointestinal tract. Limited data exists on the efficacy of SZC for the treatment of acute hyperkalemia. Objectives: To assess the achievement of normokalemia (serum potassium level [K+] 3.5-5.2 mmol/L) within 24 hours after administration of SZC or SPS in combination with insulin regular IV push. Methods: A multicenter, retrospective chart review (2020-2021) using electronic medical records at an academic health system. The study population included adult patients receiving one or more doses of SZC or SPS in combination with IV insulin for acute hyperkalemia (K+ >5.2 mmol/L). Patients receiving dialysis were excluded. Serum chemistries were assessed at baseline and an additional 2 values within 24 hours to determine normokalemia and hypokalemia at each follow-up. Results: Of 141 patients included, 51 received SZC and 90 received SPS. Normokalemia at the first follow-up was achieved in 51.0% of patients receiving SZC and 46.7% of patients receiving SPS (P = .622) and was sustained in 35.3%versus 44.4% (P = .289) of patients within 24 hours. Mean serum potassium differences from baseline to first follow-up were similar between SZC and SPS groups (0.9 mmol/L vs 1.0 mmol/L). Hypokalemia within 24 hours of administration occurred in 4 patients-1 in SZC, 3 in SPS. Conclusion: Both SZC and SPS yielded similar rates of normokalemia achievement with IV insulin for the treatment of acute hyperkalemia. Further prospective studies are needed to confirm these findings.

Upper Gastrointestinal Bleeding Secondary to Sodium Polystyrene Sulfonate Use: A Rare Adverse Effect of Commonly Prescribed Treatment

We report a case of a 62-year-old man who was brought in by emergency medical services after a fall and change in mental status. He was found to have severe hyperkalemia, acute kidney injury, and rhabdomyolysis. The hyperkalemia was treated with sodium polystyrene sulfonate (SPS). During hospitalization, he witnessed having black tarry stools along with a significant drop in hemoglobin. Endoscopic evaluation demonstrated nonbleeding large diffuse gastric ulcers with stigmata of recent bleeding, and ulcer biopsy revealed findings consistent with SPS-induced gastric ulceration. No other source of bleeding was localized, suggesting acute upper gastrointestinal bleeding due to SPS mucosal injury.

Potassium homeostasis and therapeutic intervention with sodium zirconium cyclosilicate: A model-informed drug development case study

Potassium (K+ ) is the main intracellular cation in the body. Elevated K+ levels (hyperkalemia) increase the risk of life-threatening arrhythmias and sudden cardiac death. However, the details of K+ homeostasis and the effects of orally administered K+ binders, such as sodium zirconium cyclosilicate (SZC), on K+ redistribution and excretion in patients remain incompletely understood. We built a fit-for-purpose systems pharmacology model to describe K+ homeostasis in hyperkalemic subjects and capture serum K+ (sK+ ) dynamics in response to acute and chronic administration of SZC. The resulting model describes K+ distribution in the gastrointestinal (GI) tract, blood, and extracellular and intracellular spaces of tissue, renal clearance of K+ , and K+ -SZC binding and excretion in the GI tract. The model, which was fit to time-course sK+ data for individual patients from two clinical trials, accounts for bolus delivery of K+ in meals and oral doses of SZC. The virtual population of patients derived from fitting the model to these trials was then modified to predict the SZC dose-response and inform clinical trial design in two new applications: emergency lowering of sK+ in severe hyperkalemia and prevention of hyperkalemia between dialysis sessions in patients with end-stage chronic kidney disease. In both cases, the model provided novel and useful insight that was borne out by the now completed clinical trials, providing a concrete case study of fit-for-purpose, model-informed drug development after initial approval of a drug.

Strategies to prevent, diagnose and treat kidney disease related to systemic arterial hypertension: a narrative review from the Mexican Group of Experts on Arterial Hypertension

This narrative review highlights strategies proposed by the Mexican Group of Experts on Arterial Hypertension endorsed to prevent, diagnose, and treat chronic kidney disease (CKD) related to systemic arterial hypertension (SAH). Given the growing prevalence of CKD in Mexico and Latin America caused by SAH, there is a need for context-specific approaches to address the effects of SAH, given the diverse population and unique challenges faced by the region. This narrative review provides clinical strategies for healthcare providers on preventing, diagnosing, and treating kidney disease related to SAH, focusing on primary prevention, early detection, evidence-based diagnostic approaches, and selecting pharmacological treatments. Key-strategies are focused on six fundamental areas: 1) Strategies to mitigate kidney disease in SAH, 2) early detection of CKD in SAH, 3) diagnosis and monitoring of SAH, 4) blood pressure targets in patients living with CKD, 5) hypertensive treatment in patients with CKD and 6) diuretics and Non-Steroidal Mineralocorticoid Receptor Inhibitors in Patients with CKD. This review aims to provide relevant strategies for the Mexican and Latin American clinical context, highlight the importance of a multidisciplinary approach to managing SAH, and the role of community-based programs in improving the quality of life for affected individuals. This position paper seeks to contribute to reducing the burden of SAH-related CKD and its complications in Mexico and Latin America.

Consensus document on the management of hyperkalemia

Hyperkalaemia is a common electrolyte imbalance with potentially serious short-, medium- and long-term consequences on morbidity and mortality rates and the use of national health service resources. The fact that different medical specialities can manage hyperkalaemia makes it important to have a unified approach, and the recent availability of new specific drug treatments means that the approach needs to be updated. This consensus document from the scientific societies most directly involved in the management of hyperkalaemia (Sociedad Española de Cardiología [Spanish Society of Cardiology], Sociedad Española de Endocrinología y Nutrición [Spanish Society of Endocrinology and Nutrition], Sociedad Española de Medicina Interna [Spanish Society of Internal Medicine], Sociedad Española de Medicina de Urgencias y Emergencias [Spanish Society of Accident and Emergency Medicine] and Sociedad Española de Nefrología [Spanish Society of Nephrology]) first of all reviews basic aspects of potassium balance and blood potassium. Then it goes on to focus on the concept, epidemiology, pathophysiology and diagnostic and therapeutic approaches to hyperkalaemia. The available evidence and the main published studies have been reviewed with the aim of providing a useful tool in the multidisciplinary approach to patients with hyperkalaemia.

Comparison of effectiveness and safety of sodium polystyrene sulfonate and sodium zirconium cyclosilicate for treatment of hyperkalemia in hospitalized patients

PURPOSE

Potassium binders are frequently utilized for the treatment of hyperkalemia in hospitalized patients; however, there is limited data directly comparing individual agents. The purpose of this study was to compare the effectiveness and safety of sodium polystyrene sulfonate (SPS) and sodium zirconium cyclosilicate (SZC) for hyperkalemia treatment in hospitalized patients.

METHODS

This retrospective cohort study evaluated adult patients who were admitted within a 7-hospital health system and received SPS or SZC for a serum potassium level greater than 5.0 mEq/L. Patients receiving dialysis prior to SPS/SZC administration, those receiving other potassium-lowering medications within 6 hours prior to blood sampling for a repeat potassium level, and those started on kidney replacement therapy prior to sampling for a repeat potassium level were excluded.

RESULTS

Following evaluation of 3,903 patients, the mean reduction in serum potassium 4 to 24 hours after binder administration was 0.96 mEq/L with SPS and 0.78 mEq/L with SZC (P < 0.0001). The median dose of SPS was 30 g (interquartile range [IQR], 15-30 g) while the median (IQR) dose of SZC was 10 g (10-10 g). Resolution of hyperkalemia within 24 hours was achieved in a higher percentage of patients with use of SPS (74.9%) versus SZC (68.8%) (P < 0.001).

CONCLUSION

One of the largest comparisons of SPS and SZC conducted to date, this study demonstrated the effectiveness and safety of both agents. While a statistically greater reduction in serum potassium was observed with use of SPS, there was significant dosing variability among agents that limited the ability to directly compare specific doses. Further investigation is needed to determine the optimal dose of each agent for acute hyperkalemia management. This data will inform clinical decisions about the choice of potassium binder for acute hyperkalemia.

Single Dose of Sodium Zirconium Cyclosilicate Versus Sodium Polystyrene Sulfonate in Hospitalized Patients With Hyperkalemia

BACKGROUND

Sodium zirconium cyclosilicate (SZC) is an inorganic zirconium silicate compound that selectively exchanges potassium for hydrogen and sodium. "Once" doses of SZC (with option to redose) in patients with hyperkalemia in hospitalized settings have not been evaluated. We hypothesized that a once dose of SZC would be non-inferior to sodium polystyrene sulfonate (SPS) in reducing serum potassium.

OBJECTIVE

The objective of our study is to evaluate the effect of a "once" dose of SZC when compared with SPS in reducing serum potassium levels.

METHODS

This was a retrospective analysis of patients who received either a "once" dose of SZC or single or repeated doses of SPS for hyperkalemia. The primary endpoint was mean absolute reduction in the first serum potassium value at least 4 hours after administration. The secondary efficacy endpoints were the rate of additional potassium-lowering therapies and the rate of normokalemia within 48 hours. Safety endpoints were the incidence of electrolyte abnormalities, hypoglycemia, hypertension, hypotension, and colonic necrosis.

RESULTS

A total of 260 patients were included in the analysis. The mean initial serum potassium was similar between groups (5.6 ± 0.4). The absolute serum potassium reduction was -0.88 ± 0.64 mEq/L and -0.75 ± 0.65 mEq/L with SZC and SPS, respectively. The "once" regimen of SZC demonstrated non-inferiority compared with SPS (P < 0.0001). The proportion of patients achieving normokalemia within 48 hours and the proportion of patients receiving additional potassium-lowering therapies did not differ between groups.

CONCLUSION AND RELEVANCE

The "once" dose regimen (with redose option) of SZC was non-inferior to the "once" or repeated dosing regimen of SPS with regard to absolute potassium reduction. There were no significant differences in the rate of additional potassium-lowering therapies and the rate of normokalemia at 48 hours. The incidence of hypertension was less common among patients who received SZC.

Pharmacological strategies to manage hyperkalaemia: out with the old, in with the new? Not so fast…

Since the 1950s, sodium polystyrene sulphonate (SPS) has been the dominant cation exchange agent prescribed for hyperkalaemia. Clinicians have had plenty of time to learn of SPS's advantages and limitations. The demands of drug regulatory agencies regarding the incorporation of medications into the market were not so stringent then as they are today, and the efficacy and safety of SPS have been questioned. In recent years, two novel cation exchangers, patiromer and sodium zirconium cyclosilicate, have received (or are in the process of receiving) regulatory approval in multiple jurisdictions globally, after scrutiny of carefully conducted trials regarding their short-term and mid-term efficacy. In this debate, we defend the view that all three agents are likely to have similar efficacy. Harms are much better understood for SPS than for newer agents, but currently there are no data to suggest that novel agents are safer than SPS. Drug choices need to consider costs, access and numbers-needed-to-treat to prevent clinically important events; for potassium exchangers, we need trials directly examining clinically important events.

Patiromer utility as an adjunct treatment in patients needing urgent hyperkalaemia management (PLATINUM): design of a multicentre, randomised, double-blind, placebo-controlled, parallel-group study

INTRODUCTION

Hyperkalaemia is common, life-threatening and often requires emergency department (ED) management; however, no standardised ED treatment protocol exists. Common treatments transiently reducing serum potassium (K+) (including albuterol, glucose and insulin) may cause hypoglycaemia. We outline the design and rationale of the Patiromer Utility as an Adjunct Treatment in Patients Needing Urgent Hyperkalaemia Management (PLATINUM) study, which will be the largest ED randomised controlled hyperkalaemia trial ever performed, enabling assessment of a standardised approach to hyperkalaemia management, as well as establishing a new evaluation parameter (net clinical benefit) for acute hyperkalaemia treatment investigations.

METHODS AND ANALYSIS

PLATINUM is a Phase 4, multicentre, randomised, double-blind, placebo-controlled study in participants who present to the ED at approximately 30 US sites. Approximately 300 adult participants with hyperkalaemia (K+ ≥5.8 mEq/L) will be enrolled. Participants will be randomised 1:1 to receive glucose (25 g intravenously <15 min before insulin), insulin (5 units intravenous bolus) and aerosolised albuterol (10 mg over 30 min), followed by a single oral dose of either 25.2 g patiromer or placebo, with a second dose of patiromer (8.4 g) or placebo after 24 hours. The primary endpoint is net clinical benefit, defined as the mean change in the number of additional interventions less the mean change in serum K+, at hour 6. Secondary endpoints are net clinical benefit at hour 4, proportion of participants without additional K+-related medical interventions, number of additional K+-related interventions and proportion of participants with sustained K+ reduction (K+ ≤5.5 mEq/L). Safety endpoints are the incidence of adverse events, and severity of changes in serum K+ and magnesium.

ETHICS AND DISSEMINATION

A central Institutional Review Board (IRB) and Ethics Committee provided protocol approval (#20201569), with subsequent approval by local IRBs at each site, and participants will provide written consent. Primary results will be published in peer-reviewed manuscripts promptly following study completion.

TRIAL REGISTRATION NUMBER

NCT04443608.

A randomized study to compare oral potassium binders in the treatment of acute hyperkalemia

BACKGROUND

The KBindER (K⁺ Binders in Emergency Room and hospitalized patients) clinical trial is the first head-to-head evaluation of oral potassium binders (cation-exchange resins) for acute hyperkalemia therapy.

METHODS

Emergency room and hospitalized patients with a blood potassium level ≥ 5.5 mEq/L are randomized to one of four study groups: potassium binder drug (sodium polystyrene sulfonate, patiromer, or sodium zirconium cyclosilicate) or nonspecific laxative (polyethylene glycol). Exclusion criteria include recent bowel surgery, ileus, diabetic ketoacidosis, or anticipated dialysis treatment within 4 h of treatment drug. Primary endpoints include change in potassium level at 2 and 4 h after treatment drug. Length of hospital stay, next-morning potassium level, gastrointestinal side effects and palatability will also be analyzed. We are aiming for a final cohort of 80 patients with complete data endpoints (20 per group) for comparative statistics including multivariate adjustment for kidney function, diabetes mellitus, congestive heart failure, metabolic acidosis, renin-angiotensin-aldosterone system inhibitor prescription, and treatment with other agents to lower potassium (insulin, albuterol, loop diuretics).

DISCUSSION

The findings from our study will inform decision-making guidelines on the role of oral potassium binders in the treatment of acute hyperkalemia.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04585542 . Registered 14 October 2020.

Sodium polystyrene sulfonate versus sodium zirconium cyclosilicate for the treatment of hyperkalemia in the emergency department

BACKGROUND

Hyperkalemia accounts for over 800,000 emergency department (ED) visits in the United States each year, and has been associated with significant morbidity and mortality likely due to fatal cardiac dysrhythmias. Previous studies have demonstrated reductions in mortality when potassium levels are normalized in the ED. Cation exchange resins, such as sodium polystyrene sulfonate (SPS) and sodium zirconium cyclosilicate (SZC), may be administered as a means of definitively eliminating potassium from the body. This practice is based on physician preference and is not supported by high quality data. Two studies evaluating the use of cation exchange resins versus standard treatment in the ED demonstrated reductions in serum potassium levels within two hours of administration; however, there have been no published studies investigating these agents in a head-to-head comparison.

OBJECTIVE

The purpose of this study was to evaluate the efficacy and safety of SPS versus SZC in lowering serum potassium in patients presenting to the ED with hyperkalemia.

METHODS

This was an institutional review board-approved, retrospective cohort study conducted at a single-site ED. All patients who received medications under the "ED Hyperkalemia Treatment" order set between August 26, 2019 and May 13, 2021 were eligible for inclusion. The primary outcome was the change in serum potassium from baseline to first repeat level following SPS or SZC administration in the ED.

RESULTS

A total of 885 patients were screened with 54 patients in the SPS group and 51 patients in the SZC group included in the final analyses. The mean change in serum potassium from baseline to first repeat level following administration of the cation exchange resin was -1.1 mEq/L for both groups.

CONCLUSION

Administration of SPS or SZC for the treatment of hyperkalemia in the ED resulted in similar reductions in serum potassium.

An evaluation of sodium zirconium cyclosilicate: a new treatment option for hyperkalaemia in China

INTRODUCTION

Hyperkalemia is a common complication of chronic kidney disease (CKD), diabetes mellitus (DM), and heart failure (HF) that can lead to severe arrhythmias and sudden death and is associated with a higher risk of mortality. Therefore, the prevention and treatment of hyperkalemia is important. Sodium zirconium cyclosilicate (SZC), a new oral potassium-lowering drug, has offered an additional treatment option for Chinese patients with hyperkalemia since its launch in China in late 2019, and some experience has been accumulated regarding its efficacy and safety.

AREAS COVERED

In this review, the authors summarize the epidemiological features of hyperkalemia in China and review the clinical data regarding the use of sodium zirconium cyclosilicate in Chinese patients.

EXPERT OPINION

The prevalence of hyperkalemia is particularly high in Chinese patients with chronic kidney disease and heart failure. In China, recent clinical studies have shown that SZC rapidly reduces serum potassium, maintains normal potassium concentration, and is well tolerated and safe. Two Chinese expert consensus statements have recommended the use of SZC for the acute correction and chronic maintenance of potassium concentration.

Acute hyperkalemia in adults

Hyperkalemia is a common, life-threatening medical situation in chronic renal disease patients in the emergency department (ED). Since hyperkalemia does not present with any specific symptom, it is difficult to diagnose clinically. Hyperkalemia causes broad and dramatic medical presentations including cardiac arrhythmia and sudden death. Hyperkalemia is generally determined through serum measurement in the laboratory. Treatment includes precautions to stabilize cardiac membranes, shift potassium from the extracellular to the intracellular, and increase potassium excretion. The present article discusses the management of hyperkalemia in the ED in the light of current evidence.

Hyperkalemia: Prevalence, Predictors and Emerging Treatments

It is well established that an elevated potassium level (hyperkalemia) is associated with a risk of adverse events including morbidity, mortality and healthcare system cost. Hyperkalemia is commonly encountered in many chronic conditions including kidney disease, diabetes and heart failure. Furthermore, hyperkalemia may result from the use of renin-angiotensin-aldosterone system inhibitors (RAASi), which are disease-modifying treatments for these conditions. Therefore, balancing the benefits of optimizing treatment with RAASi while mitigating hyperkalemia is crucial to ensure patients are optimally treated. In this review, we will briefly discuss the definition, causes, epidemiology and consequences of hyperkalemia. The majority of the review will be focused on management of hyperkalemia in the acute and chronic setting, emphasizing contemporary approaches and evolving data on the relevance of dietary restriction and the use of novel potassium binders.

Hyperkalaemia and potassium binders: Retrospective observational analysis looking at the efficacy and cost effectiveness of calcium polystyrene sulfonate and sodium zirconium cyclosilicate

WHAT IS KNOWN AND OBJECTIVE

Hyperkalaemia is a common medical emergency in patients admitted to hospital. There is a limited evidence base supporting some of the commonly applied treatment strategies. Although, NICE has recommended the use of sodium zirconium cyclosilicate (SZC) (TA599) and patiromer (TA623) in both acute and chronic hyperkalaemia, there is a limited evidence base for their use in acute hyperkalaemia in the hospital setting, particularly when compared to the present standard of care calcium polystyrene sulfonate (CPS).

METHODS

A retrospective review of the electronic patient record system across our hospital over a 6-month period identified 138 patients who received either SZC (65 patients) or CPS (73 patients) to manage hyperkalaemia, investigating their efficacy and cost effectiveness. Results were analysed using simple descriptive statistics. Based on the results a naïve cost comparison between the two drugs was made.

RESULTS AND DISCUSSION

CPS and SZC both effectively reduced plasm potassium concentrations in patients with hyperkalaemia (6.07 and 6.03 mmol/L respectively) by 1.17 mmol/L and 1.24 mmol/L taking a similar amount of time to work (2.97 days vs. 3 days). The principle causes of hyperkalaemia identified were acute kidney injury, medication, and chronic kidney disease. Cost comparison analysis which took into account raw product price and time needed to dispense medications revealed that CPS has slightly better cost effectiveness compared to SZC albeit at a cost of increased staff input.

WHAT IS NEW AND CONCLUSION

Both CPS and SZC were equally effective at lowering acutely raised potassium concentrations. The cost difference between the two products appears to be small. Claims regarding the benefits of newer agents over older established medications need to be properly explored in randomized trials rather than being based on small scale non-comparative studies.

Hyperkalaemia in Heart Failure: Consequences for Outcome and Sequencing of Therapy

PURPOSE OF REVIEW

Heart failure (HF), in conjunction with common comorbidities such as chronic kidney disease and diabetes and medical therapies such as RAASi, predisposes to hyperkalaemia which may lead to hospitalisation and death. This paper aims to review the most current evidence surrounding the risks and management of hyperkalaemia in HF, with particular focus on recent research into RAASi including novel selective mineralocorticoid receptor blockers and novel potassium binders.

RECENT FINDINGS

The most recent evidence shows that even moderate hyperkalaemia may predispose to adverse outcomes such as hospitalisation and death. Furthermore, it may prevent patients from receiving optimal medical therapy for HF by reducing prescription of RAASi therapy. Novel potassium binders such as sodium zirconium cyclosilicate (SZC) and patiromer present potential options to reduce and prevent hyperkalaemia as well as maintain optimal RAASi dosing in HF. Management of hyperkalaemia in HF has advanced in recent years. New therapies such as SZC and patiromer are contributing to the management of acute hyperkalaemia and also access to life-saving RAASi therapies by tackling and preventing hyperkalaemia in the community.

Hyperkalemia in Chronic Kidney Disease: Links, Risks and Management

Hyperkalemia is a common clinical problem with potentially fatal consequences. The prevalence of hyperkalemia is increasing, partially due to wide-scale utilization of prognostically beneficial medications that inhibit the renin-angiotensin-aldosterone-system (RAASi). Chronic kidney disease (CKD) is one of the multitude of risk factors for and associations with hyperkalemia. Reductions in urinary potassium excretion that occur in CKD can lead to an inability to maintain potassium homeostasis. In CKD patients, there are a variety of strategies to tackle acute and chronic hyperkalemia, including protecting myocardium from arrhythmias, shifting potassium into cells, increasing potassium excretion from the body, addressing dietary intake and treating associated conditions, which may exacerbate problems such as metabolic acidosis. The evidence base is variable but has recently been supplemented with the discovery of novel oral potassium binders, which have shown promise and efficacy in studies. Their use is likely to become widespread and offers another tool to the clinician treating hyperkalemia. Our review article provides an overview of hyperkalemia in CKD patients, including an exploration of relevant guidelines and nuances around management.

Optimizing Therapies in Heart Failure: The Role of Potassium Binders

Heart failure (HF) is a worrisome cardiac pandemic with a negative prognostic impact on the overall survival of individuals. International guidelines recommend up-titration of standardized therapies in order to reduce symptoms, hospitalization rates, and cardiac death. Hyperkalemia (HK) has been identified in 3–18% of HF patients from randomized controlled trials and over 25% of HF patients in the “real world” setting. Pharmacological treatments and/or cardio-renal syndrome, as well as chronic kidney disease may be responsible for HK in HF patients. These conditions can prevent the upgrade of pharmacological treatments, thus, negatively impacting on the overall prognosis of patients. Potassium binders may be the best option in patients with HK in order to reduce serum concentrations of K⁺ and to promote correct upgrades of therapies. In addition to the well-established use of sodium polystyrene sulfonate (SPS), two novel drugs have been recently introduced: sodium zirconium cyclosilicate (SZC) and patiromer. SZC and patiromer are gaining a central role for the treatment of chronic HK. SZC has been shown to reduce K⁺ levels within 48 h, with guaranteed maintenance of normokalemia for up to12 months. Patiromer has resulted in a statistically significant decrease in serum potassium for up to 52 weeks. Therefore, long-term results seemed to positively promote the implementation of these compounds in clinical practice due to their low rate side effects. The aim of this narrative review is to delineate the impact of new potassium binders in the treatment of patients with HF by providing a critical reappraisal for daily application of novel therapies for hyperkalemia in the HF setting.

Optimization of RAASi Therapy with New Potassium Binders for Patients with Heart Failure and Hyperkalemia: Rapid Review and Meta-Analysis

(1) Background: The objective of this rapid review is to assess whether new potassium binders (NPBs) could enable the optimization of RAASi therapy more than usual care or placebo in patients with or at risk of heart failure and hyperkalemia. (2) Methods: We searched for RCTs that included patients with or at risk of hyperkalemia and patients treated with Patiromer or sodium zirconium cyclosilicate (ZSC). The comparators were placebo, usual care, and potassium binders with different doses or different treatment protocols. We searched the Cochrane CENTRAL, MEDLINE, and ClinicalTrials.gov databases. The risk of bias was assessed using the Cochrane risk of bias tool for RCTs. Data were pooled using the random effects model, and the fixed effects model was used for sensitivity analysis. (3) Results: We included 12 studies with 2800 enrolled patients. Only three of these trials (412 patients) were included in the meta-analysis. NPBs seemed to have an effect on the optimization of MRA therapy, with an RR (95% CI) of 1.24 (1.09, 1.42) (moderate certainty evidence); Patiromer seemed to have an effect on MRA optimization, with an RR (95% CI) or 1.25 (1.08, 1.45) (high certainty evidence). ZSC seemed to have no effect on enabling MRA therapy, with an RR (95% CI) of 1.19 (0.89, 1.59) (low certainty evidence). The AEs in HF patients with hyperkalemia treated with Patiromer were GI disorders and hypomagnesemia. ZSC The AEs included chronic cardiac failure, hypokalemia, and edema. (4) Conclusions: This meta-analysis included three studies with a small number of patients and a short follow-up period (1–3 months). The evidence of the effect of NPBs on MRA optimization had a moderate certainty for imprecision. Data on the effect on MRA optimization and less severe AEs in long-term treatment seem to suggest the use of Patiromer for the optimization of MRA therapy in patients with or at risk of heart failure and hyperkalemia. Future adequately powered RCTs are needed to assess the benefits and potential harms of potassium binders.

Hyperkalemia management in the emergency department: An expert panel consensus

Hyperkalemia is a common electrolyte abnormality identified in the emergency department (ED) and potentially fatal. However, there is no consensus over the potassium threshold that warrants intervention or its treatment algorithm. Commonly used medications are at best temporizing measures, and the roles of binders are unclear in the emergent setting. As the prevalence of comorbid conditions altering potassium homeostasis rises, hyperkalemia becomes more common, and hence there is a need to standardize management. A panel was assembled to synthesize the available evidence and identify gaps in knowledge in hyperkalemia treatment in the ED. The panel was composed of 7 medical practitioners, including 5 physicians, a nurse, and a clinical pharmacist with collective expertise in the areas of emergency medicine, nephrology, and hospital medicine. This panel was sponsored by the American College of Emergency Physicians with a goal to create a consensus document for managing acute hyperkalemia. The panel evaluated the evidence on calcium for myocyte stabilization and potassium shifting and excretion. This article summarizes information on available therapies for hyperkalemia and proposes a hyperkalemia treatment algorithm for the ED practitioner based on the currently available literature and highlights diagnostic pitfalls and evidence gaps.

Hyperkalemia with RAAS inhibition: Mechanism, clinical significance, and management

Renin-angiotensin-aldosterone system (RAAS) inhibitors are evidence-based treatments for a number of conditions including hypertension, diabetes mellitus, chronic kidney disease, and congestive heart failure. Among the most common adverse effects of RAAS inhibitors is hyperkalemia which results from either reduced secretion of aldosterone or increased resistance to aldosterone. Many of the conditions for which RAAS inhibitors are recommended further amplify the risk for hyperkalemia in and of themselves. RAAS inhibitor-related hyperkalemia is associated with an increased risk for cardiovascular events, hospitalizations, and death. Yet discontinuation of RAAS inhibitors for patients with chronic kidney disease and congestive heart failure is also associated with an increased risk for cardiovascular events, hospitalizations, and death. Therefore, clinicians are often left to struggle with the dilemma of the best management approach to RAAS inhibitor-related hyperkalemia. The ideal solution involves pharmacotherapies that are safe and effective in mitigating hyperkalemia and allow patients to continue to receive the beneficial effects from RAAS inhibitors. In this regard, modern pharmacologic agents such as patiromer and zirconium cyclosilicate are providing a mechanism whereby physicians are better equipped to maintain their patients on RAAS inhibitors.

Sliding with the sines − fatal hyperkalemia: A case report

BACKGROUND

Classic electrocardiographic manifestations of hyperkalemia starting with peaked symmetrical T-waves are widely recognized in daily clinical practice but little evidence is documented how quickly it can evolve in real-time.

CASE SUMMARY

An elderly diabetic and hypertensive male presented with acute renal failure and rhabdomyolysis. He experienced cardiac arrest with moderate hyperkalemia despite medical treatment and hemodialysis. Telemetry changes were retrospectively studied and found to have significant rhythm changes that occurred just less than 10 minutes prior to the cardiac arrest.

CONCLUSION

In hyperkalemia, telemetry rhythm can change instantaneously in a significant way. Rapidly rising potassium could be life threatening and may require more than medical treatment.

Patiromer and Sodium Zirconium Cyclosilicate in Treatment of Hyperkalemia: A Systematic Review and Meta-Analysis

Background

Patiromer and sodium zirconium cyclosilicate (SZC) are newer options for hyperkalemia treatment. This systematic review and meta-analysis were conducted to assess the safety and side effect profile of patiromer and SZC compared with placebo or other standards of care in the management of hyperkalemia.

Methods

We searched electronic databases for relevant articles. The screening was performed independently and data were extracted among the selected studies. We performed a statistical analysis on Revman 5.4 software. The odds ratio (OR) was used for outcome estimation with a 95% CI.

Results

Patiromer had lower rates of hyperkalemia (OR = 0.44; 95% CI, 0.22–0.89) compared with standard of care. The analysis showed no significant differences between the 2 groups in terms of overall adverse effects, any serious/specific adverse effects, or treatment discontinuation as a result of adverse effects. Comparing the SZC-10 group with standard of care showed no significant differences in the occurrence of hyperkalemia during treatment, overall adverse effects, any serious/specific adverse effects, or treatment discontinuation as a result of adverse effects but showed a higher rate of edema in the treatment group (OR = 6.77; 95% CI, 1.03–44.25). Similarly, no significant differences were seen between the 2 SZC doses for the occurrence of any adverse effects, hyperkalemia, constipation, diarrhea, or urinary tract infection, whereas edema was higher among patients receiving SZC-10 (OR = 3.13; 95% CI, 1.19–8.27).

Conclusions

In patients with acute hyperkalemia, SZC is the drug of choice due to its more rapid reduction of serum potassium level, whereas in patients with chronic hyperkalemia, patiromer appears to be the drug of choice because SZC is associated with an increase in edema, likely due to an increase in sodium absorption, which could have important adverse consequences in patients with chronic kidney disease and or heart failure. Thus, both drugs were found to be safe while treating hyperkalemia. (Curr Ther Res Clin Exp. 2021; 82:XXX–XXX)

[Cardiac arrest under special circumstances]

These guidelines of the European Resuscitation Council (ERC) Cardiac Arrest under Special Circumstances are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the modifications required for basic and advanced life support for the prevention and treatment of cardiac arrest under special circumstances; in particular, specific causes (hypoxia, trauma, anaphylaxis, sepsis, hypo-/hyperkalaemia and other electrolyte disorders, hypothermia, avalanche, hyperthermia and malignant hyperthermia, pulmonary embolism, coronary thrombosis, cardiac tamponade, tension pneumothorax, toxic agents), specific settings (operating room, cardiac surgery, cardiac catheterization laboratory, dialysis unit, dental clinics, transportation [in-flight, cruise ships], sport, drowning, mass casualty incidents), and specific patient groups (asthma and chronic obstructive pulmonary disease, neurological disease, morbid obesity, pregnancy).

Hyperkalaemia in Heart Failure

Hyperkalaemia has become an increasingly prevalent finding in patients with heart failure (HF), especially with renin–angiotensin–aldosterone system (RAAS) inhibitors and angiotensin–neprilysin inhibitors being the cornerstone of medical therapy. Patients living with HF often have other comorbidities, such as diabetes and chronic kidney disease, which predispose to hyperkalaemia. Until now, we have not had any reliable or tolerable therapies for the treatment of hyperkalaemia to facilitate implementation or achievement of target doses of RAAS inhibition. Patiromer sorbitex calcium and sodium zirconium cyclosilicate are two novel potassium-binding resins that have shown promise in the management of patients predisposed to developing recurrent hyperkalaemia, and their use may allow for further optimisation of guideline directed medical therapy.

Management of Chronic Hyperkalemia in Patients With Chronic Kidney Disease: An Old Problem With News Options

Hyperkalemia is one of the main electrolyte disorders in patients with chronic kidney disease (CKD). The prevalence of hyperkalemia increases as the Glomerular Filtration Rate (GFR) declines. Although chronic hyperkalemia is not a medical emergency, it can have negative consequences for the adequate cardio-renal management in the medium and long term. Hyperkalemia is common in patients on renin-angiotensin-aldosterone system inhibitors (RAASi) or Mineralocorticoid Receptor Antagonists (MRAs) and can affect treatment optimization for hypertension, diabetes mellitus, heart failure (HF), and CKD. Mortality rates are higher with suboptimal dosing among patients with CKD, diabetes or HF compared with full RAASi dosing, and are the highest among patients who discontinue RAASis. The treatment of chronic hyperkalemia is still challenging. Therefore, in the real world, discontinuation or reduction of RAASi therapy may lead to adverse cardiorenal outcomes, and current guidelines differ with regard to recommendations on RAASi therapy to enhance cardio and reno-protective effects. Treatment options for hyperkalemia have not changed much since the introduction of the cation exchange resin over 50 years ago. Nowadays, two new potassium binders, Patiromer Sorbitex Calcium, and Sodium Zirconium Cyclosilicate (SZC) already approved by FDA and by the European Medicines Agency, have demonstrated their clinical efficacy in reducing serum potassium with a good safety profile. The use of the newer potassium binders may allow continuing and optimizing RAASi therapy in patients with hyperkalemia keeping the cardio-renal protective effect in patients with CKD and cardiovascular disease. However, further research is needed to address some questions related to potassium disorders (definition of chronic hyperkalemia, monitoring strategies, prediction score for hyperkalemia or length for treatment).

The pharmacotherapeutic management of hyperkalemia in patients with cardiovascular disease

Introduction: Patients with cardiovascular diseases (CVD) are at increased risk of hyperkalemia, particularly when treated with renin-angiotensin-aldosterone inhibitors (RAASIs). Because the occurrence or fear of hyperkalemia, RAASIs are frequently down-titrated or discontinued in patients with CVD, with consequent worse outcomes than patients who remain on maximum doses.Areas covered: This article reviews potassium homeostasis, epidemiology, risk factors, and outcomes of hyperkalemia, and efficacy and safety of the drugs used for acute and chronic treatment of hyperkalemia. A literature search was carried out using the PubMed and guidelines for the management of hyperkalemia.Expert opinion: The emergency treatment of hyperkalemia is not supported by high-quality evidence and clinical trials did not report drug effects on clinical outcomes. Two potassium binders, patiromer and sodium zirconium cyclosilicate, represent a new approach in the treatment of chronic hyperkalemia as they may allow the titration and maintenance of guidelines-recommended doses of RAASIs in patients with CVD who otherwise would not tolerate them due to the risk of hyperkalemia.Further studies are needed to evaluate the safety and efficacy of drug therapy and support the development of guidelines for acute and chronic hyperkalemia.

European Resuscitation Council Guidelines 2021: Cardiac arrest in special circumstances

These European Resuscitation Council (ERC) Cardiac Arrest in Special Circumstances guidelines are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the modifications required to basic and advanced life support for the prevention and treatment of cardiac arrest in special circumstances; specifically special causes (hypoxia, trauma, anaphylaxis, sepsis, hypo/hyperkalaemia and other electrolyte disorders, hypothermia, avalanche, hyperthermia and malignant hyperthermia, pulmonary embolism, coronary thrombosis, cardiac tamponade, tension pneumothorax, toxic agents), special settings (operating room, cardiac surgery, catheter laboratory, dialysis unit, dental clinics, transportation (in-flight, cruise ships), sport, drowning, mass casualty incidents), and special patient groups (asthma and COPD, neurological disease, obesity, pregnancy).

Clinical Management of Hyperkalemia

Hyperkalemia is an electrolyte abnormality with potentially life-threatening consequences. Despite various guidelines, no universally accepted consensus exists on best practices for hyperkalemia monitoring, with variations in precise potassium (K⁺) concentration thresholds or for the management of acute or chronic hyperkalemia. Based on the available evidence, this review identifies several critical issues and unmet needs with regard to the management of hyperkalemia. Real-world studies are needed for a better understanding of the prevalence of hyperkalemia outside the clinical trial setting. There is a need to improve effective management of hyperkalemia, including classification and K⁺ monitoring, when to reinitiate previously discontinued renin-angiotensin-aldosterone system inhibitor (RAASi) therapy, and when to use oral K⁺-binding agents. Monitoring serum K⁺ should be individualized; however, increased frequency of monitoring should be considered for patients with chronic kidney disease, diabetes, heart failure, or a history of hyperkalemia and for those receiving RAASi therapy. Recent clinical studies suggest that the newer K⁺ binders (patiromer sorbitex calcium and sodium zirconium cyclosilicate) may facilitate optimization of RAASi therapy. Enhancing the knowledge of primary care physicians and internists with respect to the safety profiles of these newer K⁺ binders may increase confidence in managing patients with hyperkalemia. Lastly, the availability of newer K⁺-binding agents requires further study to establish whether stringent dietary K⁺ restrictions are needed in patients receiving K⁺-binder therapy. Individualized monitoring of serum K⁺ among patients with an increased risk of hyperkalemia and the use of newer K⁺-binding agents may allow for optimization of RAASi therapy and more effective management of hyperkalemia.

LONG-TERM MORTALITY AND TRAJECTORY OF POTASSIUM MEASUREMENTS FOLLOWING AN EPISODE OF ACUTE SEVERE HYPERKALEMIA

BACKGROUND

Hyperkalemia is a common condition in patients with comorbidities such as chronic kidney disease (CKD) or congestive heart failure. Moreover, severe hyperkalemia is a potentially life-threatening condition that is associated with a higher risk of adverse clinical events such as ventricular arrhythmias and sudden cardiac death. Currently, data regarding the prognostic implications of chronic hyperkalemia are available; however, the information about the long-term clinical consequences after an episode of severe hyperkalemia remains scarce. The objective of the study was to evaluate the association between the trajectory of potassium measurements in patients with acute hyperkalemia and long-term all-cause mortality.

METHODS

This is a retrospective observational study that included patients with acute severe hyperkalemia (K > 6 mEq/L) without hemolysis in the emergency room of Dr. Peset University Hospital in Valencia, Spain searching the lab database from January 2016 to March 2017. The multivariable-adjusted association of serum potassium with mortality was assessed by using comprehensive state-of-the-art regression methods that can accommodate time-dependent exposure modelling.

RESULTS

We found 172 episodes of acute hyperkalemia in 160 patients in the emergency room. The mean age of the sample was 77 ± 12 years and 60.5% were males. The most frequent comorbidities were CKD (71.2%), heart failure (35%) and diabetes mellitus (56.9%). Only 11.9% of the patients were on chronic dialysis. A quarter of the patients did not have previous CKD making hyperkalemia as an unpredictable life-threatening complication. During the acute episode, mean potassium and eGFR were 6.6 ± 0.6 (range: 6,1-9,2), and eGFR: 23 ± 16 (r : 2-84). After a median follow-up of 17.3 (IQR: 2.2-23.7) months, 68 patients died (42.5%). Recurrences of hyperkalemia (K > 5.5 mEq/L) were detected in 39.5%% of the patients who were monitored during follow-up. We found that previous potassium levels during an acute severe hyperkalemia episode were not predictors of mortality. Conversely, the post-discharge longitudinal trajectories of potassium were able to predict all-cause mortality (overall p-value = 0.0015). The effect of transitioning from hyperkalemia to normokalaemia (K > 5.5 to K ≤ 5.5 after the acute episode was significant and inversely associated with the risk of mortality.

CONCLUSION

The potassium levels prior to a severe hyperkalemic event do not predict mortality. Conversely, following an episode of acute severe hyperkalemia, serial kinetic of potassium trajectories predicts the risk of death. Further evidence is needed to confirm these findings and clarify the optimal long-term management of these patients.

Effects and Safety of a Novel Oral Potassium-Lowering Drug-Sodium Zirconium Cyclosilicate for the Treatment of Hyperkalemia: a Systematic Review and Meta-Analysis

Background

Oral sodium zirconium cyclosilicate (SZC) is a novel potassium binder capable of achieving a rapid reduction of serum potassium (sK⁺) and maintaining a long-term normokalemia. We undertook a meta-analysis to summarize and evaluate the effects surrounding SZC in patients with hyperkalemia.

Method

We searched data sources from MEDLINE (from 1950 to Sep 2020), EMBASE (from 1970 to Sep 2020), and the Cochrane Library database (from 1950 to Sep 2020) for eligible studies. All randomized controlled trials (RCTs) regarding comparison of therapeutic effects of SZC in hyperkalemia participants were included.

Results

Seven studies, including 1697 patients with hyperkalemia, were analyzed. SZC significantly reduced mean sK⁺ (−0.42 mmol/L; 95% CI: −0.63 to −0.20 mmol/L, p = 0.0001) compared with placebo, with a significantly greater proportion of patients with normokalemia (RR 3.48, 95% CI 1.49 to 8.11, p = 0.004). Subgroup analyses showed that the longer durations of SZC treatment, the greater magnitudes of potassium reduction when compared with those of placebo (p between subgroups = 0.01) at correction phase. Besides, it also demonstrated sK⁺ tended to decrease more in patients who got longer treatment or larger dosage of SZC at maintenance phase; however, the difference did not reach statistical significance. Additionally, the drug was equally effective in studies with larger than 50% of patients with chronic kidney disease (CKD) or diabetes or patients using renin-angiotensin aldosterone system inhibitor (RAAS) inhibitors (all p < 0.05). The risk of edema (4.30, 1.17 to 15.84; p = 0.03) in SZC group was higher than those of placebo group. No statistically significant differences in the risks of other adverse events were observed between the two groups.

Conclusions

SZC effectively decreased the sK⁺ level in patients with hyperkalemia within 48 h and had benefits in the long-term control of serum potassium in patients who continued to receive SZC with a favorable safety profile from available data.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10557-020-07134-2.

An Evidence-Based Narrative Review of the Emergency Department Management of Acute Hyperkalemia

BACKGROUND

The normal range for potassium is within narrow limits. Hyperkalemia is an electrolyte disorder that frequently affects patients in the emergency department (ED), and can result in significant morbidity and mortality if not identified and treated rapidly.

OBJECTIVE

This article provides an evidence-based narrative review of the management of hyperkalemia, with focused updates for the emergency clinician.

METHODS

We searched in MEDLINE, EMBASE, Web of Science, and Scopus databases for articles in English published in peer-reviewed journals and indexed up until May 2020. We used multiple search terms, including hyperkalemia, potassium, acute hyperkalemia, emergency department, dyskalemia, potassium disorders, kidney disease, epidemiology, electrolyte disturbance, severe hyperkalemia, and emergency management.

DISCUSSION

In the ED, interventions aimed to protect patients from the immediate dangers of elevated serum potassium are divided into the following: stabilizing cardiac membrane potentials, reducing serum potassium levels through shift from the extracellular fluid to intracellular fluid, and elimination of potassium through excretion via urinary or fecal excretion. Calcium is widely recommended to stabilize the myocardial cell membrane, but additional research is necessary to establish criteria for use, dosages, and preferred solutions. Redistribution of potassium ions from the bloodstream into the cells is based on intravenous insulin or nebulized β2-agonists.

CONCLUSIONS

Hyperkalemia is a frequent electrolyte disorder in the ED. Because of the risk of fatal dysrhythmia due to cardiac membrane instability, hyperkalemia is a medical emergency. There is a lack of scientific evidence on the optimal management of hyperkalemia and more research is needed to establish optimal strategies to manage acute hyperkalemia in the emergency department.

COVID-19-associated acute kidney injury: consensus report of the 25th Acute Disease Quality Initiative (ADQI) Workgroup

Kidney involvement in patients with coronavirus disease 2019 (COVID-19) is common, and can range from the presence of proteinuria and haematuria to acute kidney injury (AKI) requiring renal replacement therapy (RRT; also known as kidney replacement therapy). COVID-19-associated AKI (COVID-19 AKI) is associated with high mortality and serves as an independent risk factor for all-cause in-hospital death in patients with COVID-19. The pathophysiology and mechanisms of AKI in patients with COVID-19 have not been fully elucidated and seem to be multifactorial, in keeping with the pathophysiology of AKI in other patients who are critically ill. Little is known about the prevention and management of COVID-19 AKI. The emergence of regional 'surges' in COVID-19 cases can limit hospital resources, including dialysis availability and supplies; thus, careful daily assessment of available resources is needed. In this Consensus Statement, the Acute Disease Quality Initiative provides recommendations for the diagnosis, prevention and management of COVID-19 AKI based on current literature. We also make recommendations for areas of future research, which are aimed at improving understanding of the underlying processes and improving outcomes for patients with COVID-19 AKI.

COVID-19-associated acute kidney injury: consensus report of the 25th Acute Disease Quality Initiative (ADQI) Workgroup

Kidney involvement in patients with coronavirus disease 2019 (COVID-19) is common, and can range from the presence of proteinuria and haematuria to acute kidney injury (AKI) requiring renal replacement therapy (RRT; also known as kidney replacement therapy). COVID-19-associated AKI (COVID-19 AKI) is associated with high mortality and serves as an independent risk factor for all-cause in-hospital death in patients with COVID-19. The pathophysiology and mechanisms of AKI in patients with COVID-19 have not been fully elucidated and seem to be multifactorial, in keeping with the pathophysiology of AKI in other patients who are critically ill. Little is known about the prevention and management of COVID-19 AKI. The emergence of regional 'surges' in COVID-19 cases can limit hospital resources, including dialysis availability and supplies; thus, careful daily assessment of available resources is needed. In this Consensus Statement, the Acute Disease Quality Initiative provides recommendations for the diagnosis, prevention and management of COVID-19 AKI based on current literature. We also make recommendations for areas of future research, which are aimed at improving understanding of the underlying processes and improving outcomes for patients with COVID-19 AKI.

An evaluation of sodium zirconium cyclosilicate as a treatment option for hyperkalemia

INTRODUCTION

Hyperkalemia, defined as serum potassium level > 5.0 mEq/l, is associated with serious cardiac dysrhythmias, sudden death and increased mortality risk. It is common in patients with chronic kidney disease (CKD), diabetes (DM) and heart failure (HF), particularly in those treated with the renin-angiotensin-aldosterone system (RAAS) inhibitors or potassium-sparing diuretics. Although these drugs have documented renal and cardiac protective benefits, frequent hyperkalemia associated with their use often dictates administration of suboptimal doses or their discontinuation altogether. Treatment for chronic hyperkalemia in these settings has been challenging; however, the recent introduction of two new potassium-binding resins has revolutionized our approach to treating hyperkalemia.

AREAS COVERED

We review key clinical data relating to the pharmacokinetics, efficacy and safety of sodium zirconium cyclosilicate (SZC) as a treatment option for hyperkalemia.

EXPERT OPINION

SZC and Patiromer are promising new agents for lowering serum potassium in hyperkalemic patients, including those with CKD, with and without DM or HF, facilitating the use of the RAAS inhibitors for renal and cardiac protection. Recent randomized clinical trials have shown that SZC effectively lowers serum potassium and maintains normokalemia in most hyperkalemic patients. Clinical trials showed that SZC lowers serum potassium within 1 h, although it is not approved for treating acute hyperkalemia. SZC was well tolerated and associated with minimal adverse effects.

Management of Acute Kidney Injury in Coronavirus Disease 2019

Acute kidney injury is a common complication in hospitalized patients with coronavirus disease 2019. Similar to acute kidney injury associated with other conditions such as sepsis and cardiac surgery, morbidity and mortality are much higher in patients with coronavirus disease 2019 who develop acute kidney injury, especially in the intensive care unit. Management of coronavirus disease 2019-associated acute kidney injury with kidney replacement therapy should follow existing recommendations regarding modality, dose, and timing of initiation. However, patients with coronavirus disease 2019 are very hypercoagulable, and close vigilance to anticoagulation strategies is necessary to prevent circuit clotting. During situations of acute surge, where demand for kidney replacement therapy outweighs supplies, conservative measures have to be implemented to safely delay kidney replacement therapy. A collaborative effort and careful planning is needed to conserve dialysis supplies, to ensure that treatment can be safely delivered to every patient who will benefit for kidney replacement therapy.

Correction of serum potassium with sodium zirconium cyclosilicate in Japanese patients with hyperkalemia: a randomized, dose-response, phase 2/3 study

BACKGROUND

Sodium zirconium cyclosilicate (SZC) is an oral potassium binder approved to treat hyperkalemia in adults in a number of countries, including Japan.

METHODS

This phase 2/3, randomized, double-blind, placebo-controlled, dose-response study (ClinicalTrials.gov: NCT03127644) was designed to determine the efficacy and safety of SZC in Japanese adults with hyperkalemia. Patients with serum potassium (sK⁺) concentrations ≥ 5.1- ≤ 6.5 mmol/L were randomized 1:1:1 to SZC 5 g, SZC 10 g, or placebo three times daily for 48 h (six doses total). The primary efficacy endpoint was the exponential rate of change in sK⁺ over 48 h. The proportion of patients with normokalemia (sK⁺ 3.5-5.0 mmol/L) at 48 h and adverse events (AEs) were also evaluated.

RESULTS

Overall, 103 patients (mean age, 73.2 years; range 50-89 years) received SZC 5 g (n = 34), SZC 10 g (n = 36), or placebo (n = 33). The exponential rate of sK⁺ change from 0 to 48 h versus placebo was - 0.00261 (SZC 5 g) and - 0.00496 (SZC 10 g; both P < 0.0001). At 48 h, the proportions of patients with normokalemia were 85.3%, 91.7%, and 15.2% with SZC 5 g, SZC 10 g, and placebo, respectively. No serious AEs were reported. Hypokalemia (sK⁺  < 3.5 mmol/L) occurred in two patients in the SZC 10 g group; normokalemia was re-established within 6 days and no treatment-related AEs were reported.

CONCLUSION

SZC is effective and well tolerated in Japanese patients with hyperkalemia.

New Treatment Options for Hyperkalemia in Patients with Chronic Kidney Disease

Hyperkalemia may cause life-threatening cardiac and neuromuscular alterations, and it is associated with high mortality rates. Its treatment includes a multifaceted approach, guided by potassium levels and clinical presentation. In general, treatment of hyperkalemia may be directed towards stabilizing cell membrane potential, promoting transcellular potassium shift and lowering total K+ body content. The latter can be obtained by dialysis, or by increasing potassium elimination by urine or the gastrointestinal tract. Until recently, the only therapeutic option for increasing fecal K+ excretion was represented by the cation-exchanging resin sodium polystyrene sulfonate. However, despite its common use, the efficacy of this drug has been poorly studied in controlled studies, and concerns about its safety have been reported. Interestingly, new drugs, namely patiromer and sodium zirconium cyclosilicate, have been developed to treat hyperkalemia by increasing gastrointestinal potassium elimination. These medications have proved their efficacy and safety in large clinical trials, involving subjects at high risk of hyperkalemia, such as patients with heart failure and chronic kidney disease. In this review, we discuss the mechanisms of action and the updated data of patiromer and sodium zirconium cyclosilicate, considering that the availability of these new treatment options offers the possibility of improving the management of both acute and chronic hyperkalemia.

Emergency Potassium Normalization Treatment Including Sodium Zirconium Cyclosilicate: A Phase II, Randomized, Double-blind, Placebo-controlled Study (ENERGIZE)

Objectives

Sodium zirconium cyclosilicate (SZC) is a novel, highly selective potassium binder currently approved in the United States and European Union for treatment of hyperkalemia. This pilot evaluation explored the efficacy of SZC with insulin and glucose as hyperkalemia treatment in the emergency department (ED).

Methods

This exploratory, phase II, multicenter, randomized, double‐blind, placebo‐controlled study (NCT03337477) enrolled adult ED patients with blood potassium ≥ 5.8 mmol/L. Patients were randomized 1:1 to receive SZC 10 g or placebo, up to three times during a 10‐hour period, with insulin and glucose. The primary efficacy outcome was the mean change in serum potassium (sK⁺) from baseline until 4 hours after start of dosing.

Results

Overall, 70 patients were randomized (SZC n = 33, placebo n = 37), of whom 50.0% were male. Their mean (± standard deviation [±SD]) age was 59.0 (±13.8) years and mean initial sK⁺ was similar between groups (SZC 6.4 mmol/L, placebo 6.5 mmol/L). The least squares mean (±SD) sK⁺ change from baseline to 4 hours was –0.41 (±0.11) mmol/L and –0.27 (±0.10) mmol/L with SZC and placebo, respectively (difference = –0.13 mmol/L, 95% confidence interval [CI] = –0.44 to 0.17). A greater reduction in mean (±SD) sK⁺ from baseline occurred with SZC compared with placebo at 2 hours: –0.72 (±0.12) versus –0.36 (±0.11) mmol/L (LSM difference = –0.35 mmol/L, 95% CI = –0.68 to –0.02), respectively. A numerically lower proportion of patients in the SZC group required additional potassium‐lowering therapy due to hyperkalemia at 0 to 4 hours versus placebo (15.6% vs. 30.6%, respectively; odds ratio = 0.40, 95% CI = 0.09 to 1.77). Comparable proportions of patients experienced adverse events in both treatment groups at 0 to 24 hours.

Conclusions

This pilot study suggested that SZC with insulin and glucose may provide an incremental benefit in the emergency treatment of hyperkalemia over insulin and glucose alone.