Electrocardiographic manifestations of severe hyperkalemia

Efficacy of anti-hyperkalemic agents during cardiopulmonary resuscitation in out-of-hospital cardiac arrest

Aim

We assessed the efficacy of anti-hyperkalemic agents for alleviating hyperkalemia and improving clinical outcomes in patients with out-of-hospital cardiac arrest (OHCA).

Methods

This was a single-center, retrospective observational study of OHCA patients treated at tertiary hospitals between 2010 and 2020. Adult patients aged 18 or older who were in cardiac arrest at the time of arrival and had records of potassium levels measured during cardiac arrest were included. A linear regression model was used to evaluate the relationship between changes in potassium levels and use of anti-hyperkalemic medications. Cox proportional hazards regression analysis was performed to analyze the relationship between the use of anti-hyperkalemic agents and the achievement of return of spontaneous circulation (ROSC).

Results

Among 839 episodes, 465 patients received anti-hyperkalemic medication before ROSC. The rate of ROSC was higher in the no anti-hyperkalemic group than in the anti-hyperkalemic group (55.9 % vs 47.7 %, P = 0.019). The decrease in potassium level in the anti-hyperkalemic group from pre-ROSC to post-ROSC was significantly greater than that in the no anti-hyperkalemic group (coefficient 0.38, 95 % confidence interval [CI], 0.13-0.64, P = 0.003). In Cox proportional hazards regression analysis, the use of anti-hyperkalemic medication was related to a decreased ROSC rate in the overall group (adjusted hazard ratio [aHR] 0.66, 95 % CI, 0.54-0.81, P < 0.001), but there were no differences among subgroups classified according to initial potassium levels.

Conclusions

Anti-hyperkalemic agents were associated with substantial decreases in potassium levels in OHCA patients. However, administration of anti-hyperkalemic agents did not affect the achievement of ROSC.

Beneficial Effect of Calcium Treatment for Hyperkalemia Is Not Due to "Membrane Stabilization"

OBJECTIVES

Hyperkalemia is a common life-threatening condition causing severe electrophysiologic derangements and arrhythmias. The beneficial effects of calcium (Ca2+) treatment for hyperkalemia have been attributed to "membrane stabilization," by restoration of resting membrane potential (RMP). However, the underlying mechanisms remain poorly understood. Our objective was to investigate the mechanisms underlying adverse electrophysiologic effects of hyperkalemia and the therapeutic effects of Ca2+ treatment.

DESIGN

Controlled experimental trial.

SETTING

Laboratory investigation.

SUBJECTS

Canine myocytes and tissue preparations.

INTERVENTIONS AND MEASUREMENTS

Optical action potentials and volume averaged electrocardiograms were recorded from the transmural wall of ventricular wedge preparations (n = 7) at baseline (4 mM potassium), hyperkalemia (8-12 mM), and hyperkalemia + Ca2+ (3.6 mM). Isolated myocytes were studied during hyperkalemia (8 mM) and after Ca2+ treatment (6 mM) to determine cellular RMP.

MAIN RESULTS

Hyperkalemia markedly slowed conduction velocity (CV, by 67% ± 7%; p < 0.001) and homogeneously shortened action potential duration (APD, by 20% ± 10%; p < 0.002). In all preparations, this resulted in QRS widening and the "sine wave" pattern observed in severe hyperkalemia. Ca2+ treatment restored CV (increase by 44% ± 18%; p < 0.02), resulting in narrowing of the QRS and normalization of the electrocardiogram, but did not restore APD. RMP was significantly elevated by hyperkalemia; however, it was not restored with Ca2+ treatment suggesting a mechanism unrelated to "membrane stabilization." In addition, the effect of Ca2+ was attenuated during L-type Ca2+ channel blockade, suggesting a mechanism related to Ca2+-dependent (rather than normally sodium-dependent) conduction.

CONCLUSIONS

These data suggest that Ca2+ treatment for hyperkalemia restores conduction through Ca2+-dependent propagation, rather than restoration of membrane potential or "membrane stabilization." Our findings provide a mechanistic rationale for Ca2+ treatment when hyperkalemia produces abnormalities of conduction (i.e., QRS prolongation).

Electrocardiographic Abnormalities in Patients with Hyperkalemia: A Retrospective Study in an Emergency Department in Colombia

Introduction

Hyperkalemia is a prevalent electrolyte disorder related to elevated serum potassium levels, resulting in diverse abnormal electrocardiographic findings and associated clinical signs and symptoms, often necessitating specific treatment. However, in some patients, these abnormal findings may not be present on the electrocardiogram even in elevated serum potassium levels. This study aims to identify electrocardiographic abnormalities related to the severity of hyperkalemia and the clinical outcomes in an emergency department in southwestern Colombia.

Methodology

This is a retrospective cross-sectional descriptive study. We described the electrocardiographic findings, clinical characteristics, treatment, and outcomes related to the degrees of hyperkalemia. The potential association between the severity of hyperkalemia and electrocardiographic findings was evaluated.

Results

A total of 494 patients were included. The median of the potassium level was 6.6 mEq/L. Abnormal electrocardiographic findings were reported in 61.5% of the cases. Mild and severe hyperkalemia groups reported abnormalities in 59.9% and 61.2%, respectively. The most common electrocardiography abnormalities were the peaked T wave 36.2%, followed by wide QRS 83 (16.8%). Only 1.4% of patients had adverse outcomes. The abnormal findings were registered in 61.5%. Mortality was 11.9%. The peaked T wave was the most common finding across different levels of hyperkalemia severity.

Conclusion

High serum potassium levels are related with abnormal ECG. However, patients with different degrees of hyperkalemia could not describe abnormal ECG findings. In a high proportion of patients with renal chronic disease and hyperkalemia, the abnormalities in the ECG could be minimal or absent.

Bradycardia, Renal Failure, Atrioventricular Nodal Block, Shock, and Hyperkalemia (BRASH) Syndrome-Induced Atrial Fibrillation: A Case Report

BRASH syndrome is a syndrome that comprises bradycardia, renal failure, atrioventricular nodal block, shock, and hyperkalemia. This syndrome is usually associated with a junctional rhythm. Early recognition of this clinical entity is crucial for appropriate management. In this case report, we describe a 70-year-old female who presented with BRASH syndrome-induced atrial fibrillation with a slow ventricular response.

Double counting heart rate - Littmann sign in electrocardiogram

This report highlights necessity of correctly and quickly identifying Littmann sign. Littmann sign is not common in clinical practice, which is easily overlooked by most physicians, leading to delays in the treatment of hyperkalemia. A 68 year old patient with hyperkalemia was found to have inconsistent heart rate displayed on electrocardiogram monitoring with cardiac auscultation and synchronous electrocardiogram in the early stages of onset. Hyperkalemia was highly suspected by the Littmann sign. After completing arterial blood gas analysis, hyperkalemia was identified and active potassium lowering treatment was immediately initiated. The Littmann syndrome disappeared, and the patient eventually recovered.

Sodium Bicarbonate and Calcium Chloride for the Treatment of Hyperkalemia-Induced Cardiac Arrest: A Randomized, Blinded, Placebo-Controlled Animal Study

OBJECTIVES

Current international guidelines recommend administrating calcium chloride and sodium bicarbonate to patients with hyperkalemia-induced cardiac arrest, despite limited evidence. The aim of this study was to evaluate the efficacy of calcium chloride and sodium bicarbonate on return of spontaneous circulation (ROSC) in a pig model of hyperkalemia-induced cardiac arrest.

DESIGN

A randomized, blinded, placebo-controlled experimental pig study. Hyperkalemia was induced by continuous infusion of potassium chloride over 45 minutes followed by a bolus. After a no flow period of 7 minutes, pigs first received 2 minutes of basic cardiopulmonary resuscitation and subsequently advanced life support. The first intervention dose was administered after the fifth rhythm analysis, followed by a defibrillation attempt at the sixth rhythm analysis. A second dose of the intervention was administered after the seventh rhythm analysis if ROSC was not achieved. In case of successful resuscitation, pigs received intensive care for 1 hour before termination of the study.

SETTING

University hospital laboratory.

SUBJECTS

Fifty-four female Landrace/Yorkshire/Duroc pigs (38-42 kg).

INTERVENTIONS

The study used a 2 × 2 factorial design, with calcium chloride (0.1 mmol/kg) and sodium bicarbonate (1 mmol/kg) as the interventions.

MEASUREMENTS AND MAIN RESULTS

Fifty-two pigs were included in the study. Sodium bicarbonate significantly increased the number of animals achieving ROSC (24/26 [92%] vs. 13/26 [50%]; odds ratio [OR], 12.0; 95% CI, 2.3-61.5; p = 0.003) and reduced time to ROSC (hazard ratio [HR] 3.6; 95% CI, 1.8-7.5; p < 0.001). There was no effect of calcium chloride on the number of animals achieving ROSC (19/26 [73%] vs. 18/26 [69%]; OR, 1.2; 95% CI, 0.4-4.0; p = 0.76) or time to ROSC (HR, 1.5; 95% CI, 0.8-2.9; p = 0.23).

CONCLUSIONS

Administration of sodium bicarbonate significantly increased the number of animals achieving ROSC and decreased time to ROSC. There was no effect of calcium chloride on the number of animals achieving ROSC or time to ROSC.

The Prevalence and Risk Factors of Hyperkalemia in the Outpatient Setting

Background

Hyperkalemia is a life-threatening condition in outpatient and emergency departments. Hyperkalemia is associated with more events of major adverse cardiovascular diseases, hospitalization, and death. The aim of this study is to study and assess the prevalence and risk factors for developing hyperkalemia within the Thai population.

Method

A cross-sectional observational study of 3,299 unique adult patients (≥18 years) in one calendar year (2021) with at least 1 valid serum potassium (SK) test was conducted in the outpatient department of medicine. Hyperkalemia was determined as SK ≥5.8 mmol/L without hemolysis or technical error. Clinical data and laboratory tests were collected for analysis of risk factors.

Result

2,971 patients (131 hyperkalemia and 2,840 control) were eligible. The annual prevalence of hyperkalemia was 4.41%. The mean ages of patients were 66.5 years in the hyperkalemia group and 55.9 years in the control group. Increasing age had a positive association (r = 0.220, p < 0.001) to risk of hyperkalemia, whereas the estimated glomerular filtration rate (eGFR) had an inverse association with SK level (r = -0.398, p < 0.001). The risk factors for hyperkalemia were patients with age ≥65 years (odds ratio, 2.106; 95% CI, 1.399, 3.171; p < 0.001), presence of diabetes mellitus (DM, odds ratio, 1.541; 95% CI, 1.030, 2.306; p = 0.036), chronic kidney disease (CKD) stage ≥3 (odds ratio, 14.885; 95% CI, 8.112, 27.313; p < 0.001), hemodialysis treatment (odds ratio, 10.170; 95% CI, 5.858, 17.657; p < 0.001), and usage of renin-angiotensin-aldosterone system inhibitors (RAASi, odds ratio, 2.256; 95% CI, 1.440, 3.536; p < 0.001).

Conclusion

The risk factors contributing to hyperkalemia were patients with older age, DM, CKD, hemodialysis treatment, and usage of RAASi. Although the usage of RAASi is proven to be a cardiovascular advantage in the elderly, DM, and CKD patients, careful monitoring of SK is strongly advised to optimize patient care.

Comparison of quantifiable electrocardiographic changes associated with severe hyperkalemia

BACKGROUND

Hyperkalemia (HK) is a life-threatening condition that is frequently evaluated by electrocardiogram (ECG). ECG changes in severe HK (≥ 6.3 mEq/L) are not well-characterized. This study sought to compare and correlate ECG metrics in severe HK to baseline normokalemic ECGs and serum potassium.

METHODS

A retrospective analysis of 340 severe HK encounters with corresponding normokalemic ECGs was performed.

RESULTS

Various ECG metrics were analyzed. P wave amplitude in lead II, QRS duration, T wave slope, ratio of T wave amplitude: duration, and ratios of T wave: QRS amplitudes were significantly different between normokalemic and HK ECGs. P wave amplitude attenuation in lead II correlated better with serum potassium than in V1. T wave metrics that incorporated both T wave and QRS amplitudes correlated better than metrics utilizing T wave metrics alone.

CONCLUSION

Multiple statistically significant and quantifiable differences among ECG metrics were observed between normokalemic and HK ECGs and correlated with increasing degrees of serum potassium and along the continuum of serum potassium. When incorporated into a logistic regression model, the ability to distinguish HK versus normokalemia on ECG improved significantly. These findings could be integrated into an ECG acquisition system that can more accurately identify severe HK.

Common ECG interpretation software mistakes Part II: Computer errors that hide diagnostic clues

Electrocardiogram (ECG) interpretation software mistakes can lead to incorrect diagnoses and inappropriate treatments. Occasionally, however, repetitive and consistent computer errors may hide important clues for correct diagnoses that otherwise could have been missed. We present a collection of a few common and clinically important such peculiarities, and provide tools on how to prove or disprove the suspected diagnosis. In addition to the illustrations in print, an online supplement (OS) shows more examples of the discussed phenomena. In each ECG, the original computer interpretations were enlarged for legibility.

Electrolyte Disturbances Related to Sodium and Potassium and Electroconvulsive Therapy: A Systematic Review

INTRODUCTION

Electrolyte disturbances related to sodium and potassium affect patients with mental disorders undergoing electroconvulsive therapy (ECT). The objective of this study was to systematically summarize the data regarding ECT and electrolyte disturbances related to sodium and potassium.

MATERIALS AND METHODS

A systematic literature review in accordance with PRISMA guidelines was conducted. Clinical studies of patients receiving ECT with electrolyte disturbances reported before or after treatment were included.

RESULTS

We identified nine case reports and two retrospective studies describing electrolyte abnormalities occurring before or after ECT. ECT was effective and safe in patients with hyponatremia and hypernatremia, including the elderly patient population. This treatment was also effective in treating psychiatric symptoms that may persist after ionic equalization. Electrolyte disturbances after ECT were rare. Reports have suggested that succinylcholine used as a muscle relaxant was the main cause of hyperkalemia after ECT.

CONCLUSIONS

Electrolyte control is a crucial aspect of guiding ECT therapy. In the context of sodium-related disorders, it is critical to control patient hydration as part of therapy. In addition, succinylcholine should not be used in patients with immobilization, such as catatonia or neuroleptic malignant syndrome. It is necessary to conduct further studies to clarify whether electrolyte concentration affects ECT parameters and clinical efficacy. In addition, it is necessary to assess the influence of various anesthetics on these conditions during ECT. The result of this review should be interpreted bearing in mind the small number of studies conducted to date and the low quality of the evidence they provide.

High-Dose Insulin for Hyperkalemic Cardiac Arrest

ABSTRACT

Hyperkalemic cardiac arrest diagnosis can be elusive and management difficult as the cardiac rhythm restoration is often not achieved until the potassium level decreases to a relatively normal level for the patient who suffers the arrest. Current treatment modalities can take hours to achieve this goal. We describe two patients who survived a witnessed hyperkalemic cardiac arrest after being managed with conventional advanced cardiac life support and unconventionally high doses of intravenous insulin.

Brugada Pattern, Tall Peaked T Waves, Absence of P Waves, and Broad QRS Complexes

This case report presents the electrocardiogram findings of a patient in their 70s with chest tightness and shortness of breath for 5 hours and loss of consciousness for 10 minutes.

Computer-Estimated Heart Rate vs True Heart Rate-Be Aware of the Software

This case report describes a patient in their 60s with gastrointestinal bleeding and shock with heart rate overcounting by software indicating severe hyperkalemia.

Ominous T-Wave Changes in an Older Adult With Chest Pain

This case report describes a patient in their 60s who presented to the emergency department with acute, severe precordial chest pain radiating to their left arm at night, accompanied by dyspnea, dizziness, and sweating.

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.

Cardiorenal Interactions: A Review

A complex interaction occurs between cardiac and renal function. They are intricately tied together, and a range of disorders in both the heart and kidneys can alter the function of the other. The pathophysiology is complex, and these conditions are termed cardiorenal syndromes. They can be acute and/or chronic in nature, they result in and from hemodynamic consequences, systemic congestion, and metabolic abnormalities, and they lead to dysfunction of both the heart and kidneys. The aim of this article is to provide a review for cardiologists and intensivists who are treating patients for whom cardiac and renal interactions may complicate their picture. We review acute kidney injuries, management of the complications of renal dysfunction, renal replacement therapy, and cardiorenal syndromes.

Multimodality Imaging of Sudden Cardiac Death and Acute Complications in Acute Coronary Syndrome

Sudden cardiac death (SCD) is a potentially fatal event usually caused by a cardiac arrhythmia, which is often the result of coronary artery disease (CAD). Up to 80% of patients suffering from SCD have concomitant CAD. Arrhythmic complications may occur in patients with acute coronary syndrome (ACS) before admission, during revascularization procedures, and in hospital intensive care monitoring. In addition, about 20% of patients who survive cardiac arrest develop a transmural myocardial infarction (MI). Prevention of ACS can be evaluated in selected patients using cardiac computed tomography angiography (CCTA), while diagnosis can be depicted using electrocardiography (ECG), and complications can be evaluated with cardiac magnetic resonance (CMR) and echocardiography. CCTA can evaluate plaque, burden of disease, stenosis, and adverse plaque characteristics, in patients with chest pain. ECG and echocardiography are the first-line tests for ACS and are affordable and useful for diagnosis. CMR can evaluate function and the presence of complications after ACS, such as development of ventricular thrombus and presence of myocardial tissue characterization abnormalities that can be the substrate of ventricular arrhythmias.

The conundrum of the complex relationship between acute kidney injury and cardiac arrhythmias

Acute kidney injury (AKI) is defined by a rapid increase in serum creatinine levels, reduced urine output, or both. Death may occur in 16%-49% of patients admitted to an intensive care unit with severe AKI. Complex arrhythmias are a potentially serious complication in AKI patients with pre-existing or AKI-induced heart damage and myocardial dysfunction, fluid overload, and especially electrolyte and acid-base disorders representing the pathogenetic mechanisms of arrhythmogenesis. Cardiac arrhythmias, in turn, increase the risk of poor renal outcomes, including AKI. Arrhythmic risk in AKI patients receiving kidney replacement treatment may be reduced by modifying dialysis/replacement fluid composition. The most common arrhythmia observed in AKI patients is atrial fibrillation. Severe hyperkalemia, sometimes combined with hypocalcemia, causes severe bradyarrhythmias in this clinical setting. Although the likelihood of life-threatening ventricular arrhythmias is reportedly low, the combination of cardiac ischemia and specific electrolyte or acid-base abnormalities may increase this risk, particularly in AKI patients who require kidney replacement treatment. The purpose of this review is to summarize the available epidemiological, pathophysiological, and prognostic evidence aiming to clarify the complex relationships between AKI and cardiac arrhythmias.

Potentially Life-threatening Arrhythmia Triggered by an Excessive Consumption of Dried Sweet Potato "Hoshi-Imo"

We herein report two cases of potentially life-threatening arrhythmia due to hyperkalemia triggered by the excessive consumption of "Hoshi-Imo" (dried sweet potato). Both patients with chronic renal disease on renin-angiotensin-aldosterone system inhibitors presented at the emergency room with non-specific symptoms. Electrocardiograms revealed potentially life-threatening arrhythmia due to hyperkalemia in both cases: sinus arrest with a ventricular escape rhythm, tall and peaked T waves; and a widened QRS complex in a nearly sine-wave configuration without discernible P wave. Both patients fully recovered after intensive care for hyperkalemia. Physicians should recognize the excessive consumption of "Hoshi-Imo" may lead to the development of life-threatening arrhythmia, especially in patients with risk factors for hyperkalemia.

Hyperkalaemia mimics pseudostemi infarct pattern

Hyperkalaemia is an electrolyte abnormality that warrants urgent intervention and has well-recognised electrocardiographic changes. Peaking T wave is the most appreciated ECG sign, but hyperkalaemia manifesting electrocardiographically as acute ischemia with ST segment elevation is a very rare condition. We present a case of acute kidney injury, complicated by severe hyperkalaemia causing ST segment elevation changes in ECG simulating acute myocardial infarction. Rapid serum potassium level in arterial blood gases blood test guide treatment in this case saved the need for unnecessary activation of the catheterisation lab and more importantly, saved the patient from malignant dysthymia in case of treatment delay. Aggressive treatment of hyperkalaemia resulted in successful reduction of serum potassium level; ECG changes returned to baseline without any evidence of pseudoinfarction pattern. The medical staff should be aware of this condition in order to administer correct therapy and prevent unnecessary interventions and the associated risk of complications.

An uncommon side effect from the 'king of fruit': A case report on life-threatening hyperkalaemia after eating durian fruit

Hyperkalaemia is a condition of excess potassium level that occurs as a result of increased intake, or reduced renal clearance, or both. In a severe condition, hyperkalaemia is a medical emergency that can be life-threatening especially if recognised late and left untreated. There are many causes of hyperkalaemia. However, eating durian fruit in the background of impaired kidney function is a very rare occurrence. In this article, we report a case of an elderly lady who presented with a life-threatening hyperkalaemia as a result of eating large amount of durian fruit while having multiple diarrhoeal episodes due to acute gastroenteritis that led to acute kidney injury. She was successfully treated and was discharged well. The objective of this case report is to share the rare cause of a life-threatening hyperkalaemia where prompt diagnosis and treatment initiation are crucial to prevent mortality.

BRASH Syndrome Leading to Cardiac Arrest and Diffuse Anoxic Brain Injury: An Underdiagnosed Entity

BRASH (bradycardia, renal failure, atrioventricular [AV] nodal blocking medications, shock, hyperkalemia) syndrome describes the phenomenon of profound bradycardia from a combination of hyperkalemia and use of AV nodal blocking medication with underlying renal injury. We present a case of BRASH syndrome in a patient on chronic beta-blocker therapy for his coronary artery disease who presented with life-threatening hyperkalemia and acute renal failure. Due to failure in early recognition and superimposed effect with further beta-blocker dosing, the patient developed profound bradycardia and later went into pulseless electrical activity cardiac arrest requiring cardiopulmonary resuscitation. Metabolic derangements and bradycardia later resolved with medical management, but unfortunately, the patient developed diffuse anoxic brain injury after the cardiac arrest and was declared brain dead.

Development and outcomes of hyperkalemia in hospitalized patients: potential implications for care

INTRODUCTION

While severe hyperkalemia is commonly encountered, its manifestation in hospitalized patients and related outcomes are unclear. We aimed to examine development of hyperkalemia in hospitalized patients and associated outcomes.

METHODS

Data from a county hospital electronic health record were used to assess all inpatient admissions, 2012-2016, for non-dialysis-dependent patients with ≥1 K value for development of hyperkalemia. Unadjusted odds ratios (ORs) were calculated for associations of the maximum K value with in-hospital mortality and adjusted ORs were calculated for death associated with hyperkalemia.

RESULTS

In 47,018 individual patient hospitalizations, 1.3% had a maximum K ≥6.0 mEq/L and 4.2% <3.5 mEq/L. Fifth and 95th percentiles for maximum K values were 3.5 and 5.3 mEq/L. For high-K patients with a prior K value, the mean (SD) of the immediate pre-maximum K value was 5.0 ± 1.0 mEq/L, and the mean difference in K values (immediate pre-maximum to maximum) was 1.5 ± 1.1 mEq/L; mean duration between these two K tests was 10.7 ± 14.9 hours. Compared with maximum K values 3.5 to 4.0 mEq/L, ORs for death were 37.1 (95% confidence intervals, 25.8-53.3) for K 6.0 to <6.5, 88.6 (56.8-138.2) for K ≥7.0, and 18.9 (4.3-82.2) for K <3.0 mEq/L. In adjusted models, the OR for death for K ≥6.0 mEq/L was 4.9 (3.7-6.4).

DISCUSSION/CONCLUSIONS

Peak K values ≥6.0 mEq/L were associated with mortality. Values tended to increase rapidly, limiting opportunities for detection and treatment. Systems-based approaches to detect life-threatening hyperkalemia should be studied.

Sulfamethoxazole-Trimethoprim and Hyperkalemia in an Infant

Hyperkalemia is a potentially life-threatening electrolyte abnormality in both children and adults. In the setting of elevated serum potassium concentrations, cardiac conduction disturbances and cardiac arrest may occur. In the pediatric intensive care unit (PICU) setting, the differential diagnosis of hyperkalemia may be extensive including increased potassium intake or administration, increased endogenous production, decreased renal excretion, and intracellular to extracellular shifts related to changes in acid-base status. We present a 4-month-old infant who developed hyperkalemia during the recovery phase of her PICU course for respiratory failure. A thorough investigation demonstrated that the hyperkalemia was most likely the result of the commonly used antibiotic, trimethoprim-sulfamethoxazole (Bactrim^®). Potential etiologies of hyperkalemia in the PICU patient are discussed and previous reports of hyperkalemia associated with trimethoprim-sulfamethoxazole presented.

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.

Transient Left Bundle Branch Block in the Setting of Hyperkalemia

Hyperkalemia is a potentially life-threatening condition that can lead to sudden cardiac death. We report a case of transient left bundle branch block (LBBB) pattern on an electrocardiogram (EKG) secondary to hyperkalemia in a patient with a history of end-stage renal disease. A 48-year-old female presented to the emergency department (ED) with chief complaints of weakness and shortness of breath after a missed hemodialysis session. A 12-lead EKG in the ED showed the LBBB pattern with left axis deviation, prolonged PR interval, and peaked T-waves in the precordial leads. The initial serum potassium level was 8.5 mEq/L. EKG changes resolved after correcting the serum potassium level.

Artificial intelligence for detecting electrolyte imbalance using electrocardiography

Introduction

The detection and monitoring of electrolyte imbalance is essential for appropriate management of many metabolic diseases; however, there is no tool that detects such imbalances reliably and noninvasively. In this study, we developed a deep learning model (DLM) using electrocardiography (ECG) for detecting electrolyte imbalance and validated its performance in a multicenter study.

Methods and Results

This retrospective cohort study included two hospitals: 92,140 patients who underwent a laboratory electrolyte examination and an ECG within 30 min were included in this study. A DLM was developed using 83,449 ECGs of 48,356 patients; the internal validation included 12,091 ECGs of 12,091 patients. We conducted an external validation with 31,693 ECGs of 31,693 patients from another hospital, and the result was electrolyte imbalance detection. During internal, the area under the receiving operating characteristic curve (AUC) of a DLM using a 12‐lead ECG for detecting hyperkalemia, hypokalemia, hypernatremia, hyponatremia, hypercalcemia, and hypocalcemia were 0.945, 0.866, 0.944, 0.885, 0.905, and 0.901, respectively. The values during external validation of the AUC of hyperkalemia, hypokalemia, hypernatremia, hyponatremia, hypercalcemia, and hypocalcemia were 0.873, 0.857, 0.839, 0.856, 0.831, and 0.813 respectively. The DLM helped to visualize the important ECG region for detecting each electrolyte imbalance, and it showed how the P wave, QRS complex, or T wave differs in importance in detecting each electrolyte imbalance.

Conclusion

The proposed DLM demonstrated high performance in detecting electrolyte imbalance. These results suggest that a DLM can be used for detecting and monitoring electrolyte imbalance using ECG on a daily basis.

Dyskalemias in patients with acute kidney injury presenting to the emergency department are common and independent predictors of adverse outcome

BACKGROUND

No data concerning the prevalence and risk factors of dyskalemia in acute kidney injury (AKI) exist. We investigated (a) prevalence rates, (b) risk factors and (c) outcome of hypo- and hyperkalemia in emergency patients.

METHODS

In this cross-sectional analysis, all patients admitted to the emergency department of a large public hospital in Switzerland between January 1st 2017 and December 31st 2018 with measurements of creatinine and potassium were included. Baseline characteristics, medication and laboratory data were extracted. Chart reviews were performed to identify patients with a diagnosis of chronic kidney disease (CKD) and to extract their baseline creatinine. For all other patients, the ADQI backformula was used in order to calculate baseline creatinine. AKI was graduated using creatinine criteria of the acute kidney injury network. Binary logistic regression analysis was used to identify risk factors for appearance of hyperkalemia and outcome.

RESULTS

AKI was found in 8% of patients. Hyperkalemia was present in 13% and hypokalemia in 11% of patients with AKI. AKI stage, potassium-sparing diuretics, ACE inhibitors and underlying CKD were the strongest risk factors for hyperkalemia. Hyperkalemia as well as profound hypokalemia were independently associated with prolonged length of stay and in-hospital mortality. The study is limited by its dependency on chart review data in order to identify patients with chronic kidney disease and by limitations of the ADQI backformula to calculate baseline creatinine.

CONCLUSIONS

Dyskalemias are common in emergency patients with AKI and are independent risk factors for adverse outcomes. Potassium-sparing diuretics, ACE-inhibitors, AKIN stage and CKD are predictors of hyperkalemia in AKI.

Atypical electrocardiographic findings in severe hyperkalemia with slow clinical course

A 77-year-old woman walked into the emergency department with an episode of syncope and vomiting. She had visited at an orthopedic clinic with weakness of the lower extremities 6 weeks before, but cervical and lumbar MRI findings were unremarkable. Thereafter, she developed fingertip numbness and appetite loss at 7 and 3 days, respectively, before admission. She had been prescribed with RAS inhibitors for years. Electrocardiography while in the emergency department revealed bradycardia with normal QRS and a tented T wave. Laboratory findings revealed serum potassium 9.2 mEq/L. We discontinued RAS inhibitors and β-blockers and added glucose-insulin therapy. Thereafter, her general condition gradually recovered, and her symptoms completely disappeared. Elderly patients with chronic kidney disease treated with RAS inhibitors might develop slowly progressive symptoms of hyperkalemia. Electrocardiographic findings could be atypical and inconsistent with serum potassium values.

Acute hyperkalemia in the emergency department: a summary from a Kidney Disease: Improving Global Outcomes conference

Hyperkalemia is a common electrolyte disorder observed in the emergency department. It is often associated with underlying predisposing conditions, such as moderate or severe kidney disease, heart failure, diabetes mellitus, or significant tissue trauma. Additionally, medications, such as inhibitors of the renin-angiotensin-aldosterone system, potassium-sparing diuretics, nonsteroidal anti-inflammatory drugs, succinylcholine, and digitalis, are associated with hyperkalemia. To this end, Kidney Disease: Improving Global Outcomes (KDIGO) convened a conference in 2018 to identify evidence and address controversies on potassium management in kidney disease. This review summarizes the deliberations and clinical guidance for the evaluation and management of acute hyperkalemia in this setting. The toxic effects of hyperkalemia on the cardiac conduction system are potentially lethal. The ECG is a mainstay in managing hyperkalemia. Membrane stabilization by calcium salts and potassium-shifting agents, such as insulin and salbutamol, is the cornerstone in the acute management of hyperkalemia. However, only dialysis, potassium-binding agents, and loop diuretics remove potassium from the body. Frequent reevaluation of potassium concentrations is recommended to assess treatment success and to monitor for recurrence of hyperkalemia.

Early Disseminated Lyme Carditis Inducing High-Degree Atrioventricular Block

Lyme disease is the most common tick-borne illness in the United States due to Borrelia burgdorferi infection. This case demonstrates a 20-year-old male patient presenting with complaints of annular skin rash, malaise, fever, and lightheadedness after significant outdoor exposure. Physical exam revealed multiple large targetoid lesions on the back and extremities. The rash had raised borders and centralized clearing consistent with erythema migrans chronicum. Electrocardiogram (ECG) revealed a high-degree atrioventricular (AV) block. The patient was started on intravenous ceftriaxone due to clinical suspicion for Lyme carditis. ELISA and Western blot tests were reactive for Lyme IgM and IgG, confirming the diagnosis. The AV block resolved by hospital day four and the patient was discharged with outpatient follow-up. Early identification of disease allowed for effective treatment with no adverse outcomes or sequelae.

Etiology and Treatment of Intraoperative Hyperkalemia During Posterior Spinal Fusion in an Adolescent

Hyperkalemia, defined as a serum or plasma potassium greater than 5.5 mEq/L, while an uncommon occurrence in children, is a serious medical problem that warrants immediate attention as it can result in serious cardiac arrhythmias and death. Although hyperkalemia may occur in the critically ill patient or in the setting of renal failure and insufficiency, there are limited reports of its occurrence during intraoperative care. The authors report a previously healthy, 18-year-old patient, who developed hyperkalemia intraoperatively during posterior spinal fusion to treat adolescent idiopathic scoliosis. The potential etiologies of hyperkalemia are reviewed, a differential diagnosis for the possible etiologies presented, and treatment modalities discussed.

Electrocardiographic T wave alterations and prediction of hyperkalemia in patients with acute kidney injury

Electrocardiographic (ECG) alterations are common in hyperkalemic patients. While the presence of peaked T waves is the most frequent ECG alteration, reported findings on ECG sensitivity in detecting hyperkalemia are conflicting. Moreover, no studies have been conducted specifically in patients with acute kidney injury (AKI). We used the best subset selection and cross-validation methods [via linear and logistic regression and leave-one-out cross-validation (LOOCV)] to assess the ability of T waves to predict serum potassium levels or hyperkalemia (defined as serum potassium ≥ 5.5 mEq/L). We included the following clinical variables as a candidate for the predictive models: peaked T waves, T wave maximum amplitude, T wave/R wave maximum amplitude ratio, age, and indicator variates for oliguria, use of ACE-inhibitors, sartans, mineralocorticoid receptor antagonists, and loop diuretics. Peaked T waves poorly predicted the serum potassium levels in both full and test sample (R² = 0.03 and R² = 0.01, respectively), and also poorly predicted hyperkalemia. The selection algorithm based on Bayesian information criterion identified T wave amplitude and use of loop diuretics as the best subset of variables predicting serum potassium. Nonetheless, the model accuracy was poor in both full and test sample [root mean square error (RMSE) = 0.96 mEq/L and adjR² = 0.08 and RMSE = 0.97 mEq/L, adjR² = 0.06, respectively]. T wave amplitude and the use of loop diuretics had also poor accuracy in predicting hyperkalemia in both full and test sample [area-under-curve (AUC) at receiver-operator curve (ROC) analysis 0.74 and AUC 0.72, respectively]. Our findings show that, in patients with AKI, electrocardiographic changes in T waves are poor predictors of serum potassium levels and of the presence of hyperkalemia.