Management of Hyperkalemia With Insulin and Glucose: Pearls for the Emergency Clinician

Disorders of potassium homeostasis after kidney transplantation

Disturbances of potassium balance are often encountered when managing kidney transplant recipients (KTR). Both hyperkalemia and hypokalemia may present either as medical emergencies or chronic outpatient abnormalities. Despite the high incidence of hyperkalemia and its potential life-threatening implications, consensus on its management in KTR is lacking. Hypokalemia in KTR is also well-described, although it is given less attention by clinicians compared to hyperkalemia. This article discusses the etiology, pathophysiology and management of both types of potassium disorders in KTR. Once any emergent situation has been corrected, treatment approaches include correcting insulin deficiency if present, adjusting non-immunosuppressive and immunosuppressive medications, eliminating or supplementing potassium as needed, and dietary counselling. Although commonly of multifactorial etiology, ascertaining the specific cause in a particular patient will help guide successful management. Monitoring KTR through regular laboratory testing is essential to detect serious disturbances in potassium balance since patients are often asymptomatic.

Acute Hyperkalemia Management in the Emergency Department

Acute hyperkalemia is characterized by high concentrations of potassium in the blood that can potentially lead to life-threatening arrhythmias that require emergent treatment. Therapy involves the utilization of a constellation of different agents, all targeting different goals of care. The first, and most important step in the treatment of severe hyperkalemia with electrocardiographic (ECG) changes, is to stabilize the myocardium with calcium in order to resolve or mitigate the development of arrythmias. Next, it is vital to target the underlying etiology of any ECG changes by redistributing potassium from the extracellular space with the use of intravenous regular insulin and inhaled beta-2 agonists. Finally, the focus should shift to the elimination of excess potassium from the body through the use of intravenous furosemide, oral potassium-binding agents, or renal replacement therapy. Multiple nuances and controversies exist with these therapies, and it is important to have a robust understanding of the underlying support and recommendations for each of these agents to ensure optimal efficacy and minimize the potential for adverse effects and medication errors.

Recent Progresses in Non-Dialysis Chronic Kidney Disease Patients with Hyperkalemia: Outcomes and Therapeutic Strategies

Chronic kidney disease (CKD) affects about 10% of the world's population. Hyperkalemia is a life-threatening complication in patients with CKD, as it is associated with adverse cardiovascular and kidney outcomes. There are still many challenges and questions to address to improve the currently available therapeutic strategies to treat hyperkalemia, such as how to approach the emergency management of hyperkalemia. In recent years, in addition to novel oral potassium binders, great progress has been made in the application of novel kidney protective strategies, such as mineralocorticoid receptor antagonists and sodium-glucose cotransporter 2 inhibitors (SGLT2i) in hyperkalemia therapy. This review will discuss the recent advances from clinical trials in the effective management of hyperkalemia in non-dialysis CKD patients, enhancing the knowledge of physicians and internists concerning these newer agents and providing a helpful reference for clinical practice.

Predicting hypoglycemia after treatment of hyperkalemia with insulin and glucose (Glu-K60 score)

Background

Hyperkalemia can lead to fatal cardiac arrhythmias. Ten units of intravenous (IV) regular insulin with 25 g of glucose is the mainstay for treating hyperkalemia. However, the most important complication of this treatment is hypoglycemia. We aimed to develop a scoring model to predict hypoglycemia after the treatment of hyperkalemia.

Methods

A retrospective study was conducted at a university-based hospital between January 2013 and June 2021. We included the hyperkalemic patients (> 5.3 mmol/L) who were ≥ 18 years old and treated with 10 units of IV regular insulin with 25 g of glucose. Incomplete data on posttreatment blood glucose, pregnancy, and diabetes mellitus were excluded. Endpoint was posttreatment hypoglycemia (≤ 70 mg/dL or ≤ 3.9 mmol/L). Multivariable logistic regression was used to establish a full model and a subsequently reduced model using the backward elimination method. We demonstrated the model performance using the area under the receiver operating characteristic curve (AuROC), calibration plot, and Hosmer–Lemeshow goodness-of-fit test. Internal validation was done with a bootstrap sampling procedure with 1000 replicates. Model optimism was estimated.

Results

Three hundred and eighty-five patients were included, with 97 posttreatment hypoglycemia (25.2%). The predictive model comprised the following three criteria: age > 60 years old, pretreatment blood glucose ≤ 100 mg/dL (≤ 5.6 mmol/L), and pretreatment potassium > 6 mmol/L. The AuROC of this model was 0.671 (95% confidence interval [CI] 0.608 to 0.735). The calibration plot demonstrated consistency with the original data. Hosmer–Lemeshow goodness-of-fit test showed no evidence of lack-of-fit (p 0.792); therefore, the model was also fit to the original data. Internal validation via bootstrap sampling showed a consistent AuROC of 0.670 (95% CI 0.660 to 0.670) with minimal model optimism. A high risk for posttreatment hypoglycemia was indicated if the patient met at least one of those criteria. Sensitivity and specificity were 95.9% and 14.9%, respectively.

Conclusion

High risk was indicated when at least one of the criteria was met: age > 60 years old, pretreatment blood glucose ≤ 100 mg/dL (≤ 5.6 mmol/L), and pretreatment potassium > 6 mmol/L. Blood glucose levels should frequently check in the high-risk group.

Trial registration

TCTR20210225002 (www.thaiclinicaltrials.org).

Insulin and glucose infusion could prevent euglycemic diabetic ketoacidosis associated with sodium-glucose cotransporter 2 inhibitors

Perioperative euglycemic diabetic ketoacidosis (euDKA) is a serious adverse effect of sodium-glucose cotransporter 2 inhibitor (SGLT2i) treatment. We observed perioperative euDKA immediately after discontinuing insulin infusion that was started during surgery in a patient with type 2 diabetes mellitus (T2DM) for whom empagliflozin could not be withdrawn before emergency off-pump coronary artery bypass grafting (OPCAB). Insulin infusion that was started during surgery unexpectedly prevented euDKA until its discontinuation. Therefore, we hypothesized that insulin and glucose infusion initiated at the start of emergency surgery in patients receiving SGLT2is prevents perioperative euDKA. We implemented this strategy during emergency OPCAB in another patient with T2DM who received empagliflozin 2 days before surgery and observed that the patient did not develop perioperative euDKA. With the increasing use of SGLT2is, surgeons may encounter more SGLT2i users who require emergency surgeries. The administration of insulin and glucose infusion in advance emergency surgery can prevent perioperative euDKA.

Effects of estimated glomerular filtration rate and diabetes mellitus on the effect of insulin for treating hyperkalemia during anesthesia

PURPOSE

We analyzed the effectiveness of insulin for treating hyperkalemia (≥ 5 mEq/L) during anesthesia and the effects of the estimated glomerular filtration rate (eGFR) and diabetes mellitus (DM) on the insulin treatment.

METHODS

Patients 18 years of age and older who received intravenous insulin lispro for hyperkalemia under general anesthesia between January 2010 and March 2020 were enrolled. We performed three propensity score matching analyses according to eGFR stages (eGFR ≥ 60 vs. 30 ≤ eGFR < 60 and eGFR ≥ 60 vs. eGFR < 30 mL/min/1.73 m²) and DM status.

RESULTS

The study included 475 patients. For patients with hyperkalemia during surgery, the odds ratios [ORs] of failure to decrease potassium (K⁺) after insulin treatment were higher in patients with eGFR < 30 mL/min/1.73 m² (adjusted OR 3.24; 95% confidence interval 1.38-7.64; P = 0.007) than in patients with eGFR ≥ 60 mL/min/1.73 m². There was no significant difference in the ORs of patients with 30 ≤ eGFR < 60 mL/min/1.73 m² and DM.

CONCLUSION

The patients with a low eGFR had a higher incidence of K⁺ not decreasing after insulin treatment. Periodic assessment of K⁺ may be required during anesthesia.

The Association of Insulin-dextrose Treatment with Hypoglycemia in Patients with Hyperkalemia

Treatment of hyperkalemia with intravenous insulin-dextrose is associated with a risk of hypoglycemia. We aimed to determine the factors associated with hypoglycemia (glucose < 3.9 mmol/L, or < 70 mg/dL) and the critical time window with the highest incidence. In a retrospective cohort study in a tertiary hospital network, we included 421 adult patients with a serum potassium ≥ 6.0 mmol/L who received insulin-dextrose treatment. The mean age was 70 years with 62% male predominance. The prevalence of diabetes was 60%, and 70% had chronic kidney disease (eGFR < 60 ml/min/1.73 m2). The incidence of hypoglycemia was 21%. In a multivariable logistic regression model, the factors independently associated with hypoglycemia were: body mass index (per 5 kg/m2, OR 0.85, 95% CI: 0.69-0.99, P = 0.04), eGFR < 60 mL/min/1.73 m2 (OR 2.47, 95% CI: 1.32-4.63, P = 0.005), diabetes (OR 0.57, 95% CI 0.33-0.98, P = 0.043), pre-treatment blood glucose (OR 0.84, 95% CI: 0.77-0.91, P < 0.001), and treatment in the emergency department compared to other locations (OR 2.53, 95% CI: 1.49-4.31, P = 0.001). Hypoglycemia occurred most frequently between 60 and 150 min, with a peak at 90 min. Understanding the factors associated with hypoglycemia and the critical window of risk is essential for the development of preventive strategies.

BRASH Syndrome: Bradycardia, Renal Failure, AV Blockade, Shock, and Hyperkalemia

BACKGROUND

BRASH syndrome, or Bradycardia, Renal Failure, AV blockade, Shock, and Hyperkalemia, has recently become recognized as a collection of objective findings in a specific clinical context pertaining to emergency medicine and critical care. However, there is little emergency medicine and critical care literature specifically evaluating this condition.

OBJECTIVE

We sought to define and review BRASH syndrome and identify specific management techniques that differ from the syndromes as they present individually.

DISCUSSION

BRASH syndrome is initiated by synergistic bradycardia due to the combination of hyperkalemia and medications that block the atrioventricular (AV) node. The most common precipitant is hypovolemia or medications promoting hyperkalemia or renal injury. Left untreated, this may result in deteriorating renal function, worsening hyperkalemia, and hemodynamic instability. Patients can present with a variety of symptoms ranging from asymptomatic bradycardia to multiorgan failure. BRASH syndrome should be differentiated from isolated hyperkalemia and overdose of AV-nodal blocking medications. Treatment includes fluid resuscitation, hyperkalemia therapies (intravenous calcium, insulin/glucose, beta agonists, diuresis), management of bradycardia (which may necessitate epinephrine infusion), and more advanced therapies if needed (lipid emulsion, glucagon, or high-dose insulin infusion). Understanding and recognizing the pathophysiology of BRASH syndrome as a distinct entity may improve patient outcomes.

CONCLUSIONS

BRASH syndrome can be a difficult diagnosis and is due to a combination of hyperkalemia and medications that block the AV node. Knowledge of this condition may assist emergency and critical care providers.

Abnormal Basic Metabolic Panel Findings: Implications for Nursing

In this article, the second in a new series designed to improve acute care nurses' understanding of laboratory abnormalities, the author continues her discussion of important values in the basic metabolic panel (see Back to Basics, January, for a discussion of sodium and fluid balance). Here she addresses the electrolytes potassium and chloride as well as blood urea nitrogen and creatinine, four values that are best considered together because they both reflect and impact renal function as well as acid-base homeostasis. Important etiology, clinical manifestations, and treatment concerns are also presented. Three case studies are used to integrate select laboratory diagnostic tests with history and physical examination findings, allowing nurses to develop a thorough, focused plan of care for electrolyte abnormalities and kidney disorders commonly encountered in the medical-surgical setting.

Assessment of dextrose 50 bolus versus dextrose 10 infusion in the management of hyperkalemia in the ED

INTRODUCTION

Hypoglycemia is a common adverse effect when intravenous (IV) insulin is administered for hyperkalemia. A prolonged infusion of dextrose 10% (D10) may mitigate hypoglycemia compared to dextrose 50% (D50) bolus. Our objective was to evaluate whether D10 infusion is a safe and effective alternative to D50 bolus for hypoglycemia prevention in hyperkalemic patients receiving IV insulin.

METHODS

We conducted a retrospective review of patients ≥ 18 years who presented to the emergency department (ED) with hyperkalemia (K⁺ > 5.5) and received IV insulin and D10 infusion or D50 bolus within 3 h. The primary endpoint was incidence of hypoglycemia, defined as blood glucose (BG) ≤ 70 mg/dL, in the 24 h following IV insulin administration for hyperkalemia.

RESULTS

A total of 134 patients were included; 72 in the D50 group and 62 in the D10 group. There was no difference in incidence of hypoglycemia between the D50 and D10 groups (16 [22%] vs. 16 [26%], p = 0.77). Symptomatic hypoglycemia, severe hypoglycemia, and hyperglycemia rates in the D50 and D10 groups were [5 (7%) vs. 2 (3%), p = 0.45], [5 (7%) vs. 1 (2%), p = 0.22], and [34 (47%) vs. 23 (37%), p = 0.31] respectively. Low initial BG was a predictor for developing hypoglycemia.

CONCLUSIONS

In our study, D10 infusions appeared to be at least as effective as D50 bolus in preventing hypoglycemia in hyperkalemic patients receiving IV insulin. In context of ongoing D50 injection shortages, D10 infusions should be a therapeutic strategy in this patient population.