Assessment of Patiromer Monotherapy for Hyperkalemia in an Acute Care Setting.

Importance: Hyperkalemia is a common electrolyte disorder in hospitalized patients; however, the clinical usefulness of administering patiromer for reduction of serum potassium levels in this setting is unknown. Objective: To evaluate the outcomes associated with patiromer as monotherapy in patients with acute hyperkalemia in an acute care setting. Design, Setting, and Participants: This cohort study used electronic health record data from adult patients treated with patiromer for acute hyperkalemia in emergency departments, inpatient units, and intensive care units at an urban, academic medical center in the Bronx, New York, between January 30, 2018, and December 30, 2019. Data analysis was conducted between June 2020 and February 2021. Exposures: A single dose of oral patiromer (8.4 g, 16.8 g, or 25.2 g). Main Outcomes and Measure: The primary outcome was the mean absolute reduction in serum potassium level from baseline at 3 distinct time intervals after patiromer administration: 0 to 6 hours, greater than 6 to 12 hours, and greater than 12 to 24 hours. Key secondary outcomes were the incidence of hypokalemia and potassium reduction stratified by baseline potassium level and care setting. Results: Among 881 encounters of patiromer treatment, the mean (SD) age of patients was 67.4 (14.4) years; 463 encounters (52.6%) were for male patients, and most (338 [38.4%]) were for patients who identified as non-Hispanic Black. The mean (SD) baseline serum potassium level was 5.60 (0.35) mEq/L (to convert to mmol/L, multiply by 1.0), and within the first 6 hours after patiromer administration, the mean (SD) potassium reduction was 0.50 (0.56) mEq/L (P < .001). Both absolute and relative potassium reduction from baseline varied across baseline hyperkalemia severity but not by care setting. The lowest dose of patiromer (8.4 g) was used in 721 encounters (81.8%), and in 725 encounters (82.3%), no further doses of a potassium binder were required. Hypokalemia was noted in 2 encounters (0.2%) at 24 hours after patiromer administration. Conclusions and Relevance: In this cohort study of patients with acute, non-life-threatening hyperkalemia, a single dose of patiromer was associated with a significant decrease in serum potassium levels and a low incidence of hypokalemia. These findings suggest that patiromer monotherapy may be useful in an institutional setting for managing elevated potassium levels and minimizing the risk of hypokalemia associated with other potassium control measures.

Epidemiology, prognosis and management of potassium disorders in Covid-19.

Coronavirus disease (Covid-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is currently the largest health crisis facing most countries. Several factors have been linked with a poor prognosis for this disease, including demographic factors, pre-existing comorbidities and laboratory parameters such as white blood cell count, D-dimer, C-reactive protein, albumin, lactate dehydrogenase, creatinine and electrolytes. Electrolyte abnormalities particularly potassium disorders are common among Covid-19 patients. Based on our pooled analysis, hypokalemia and hyperkalemia occur in 24.3% and 4.15% of Covid-19 patients, respectively. Potassium level deviation from the normal range may increase the chances of unfavorable outcomes and even death. Therefore, this article reviewed the epidemiology of potassium disorders and explained how hypokalemia and hyperkalemia are capable of deteriorating cardiac outcomes and the prognosis of Covid-19 for infected patients. The article finishes by highlighting some important considerations in the management of hypokalemia and hyperkalemia in these patients.

Assessment of a downsized potassium adsorption filter designed to transfuse neonates.

BACKGROUND: During storage, the potassium level of red blood cell (RBC) components increases, especially after irradiation. Neonates are prone to hyperkalemia, for example, non-oliguric hyperkalemia, so using potassium adsorption filters during transfusion may be helpful. To overcome dilution of RBC components caused by saline priming of existing potassium adsorption filters, a downsized potassium adsorption filter for neonates (PAF-n, Kawasumi Laboratories Inc., Tokyo, Japan) was developed. STUDY DESIGN AND METHODS: To assess the performance of PAF-n, its adsorption efficiency and RBC recovery rate were evaluated by testing pre-filtration and serial post-filtration (0-30 mL, 30-60 mL, 60-90 mL, and 90-120 mL) samples from 8 RBC components. RESULTS: The average potassium adsorption rate of the PAF-n was 90.5% ± 0.78%, and never less than 89.0% in any of 8 RBC components. RBC recovery rates were 99.3% ± 1.12%. CONCLUSION: The PAF-n showed an effective potassium ability with negligible RBC dilution.

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.

Racial and Ethnic Differences in Mortality Associated with Serum Potassium in Incident Peritoneal Dialysis Patients.

BACKGROUND: Abnormalities in serum potassium are risk factors for sudden cardiac death and arrhythmias among dialysis patients. Although a previous study in hemodialysis patients has shown that race/ethnicity may impact the relationship between serum potassium and mortality, the relationship remains unclear among peritoneal dialysis (PD) patients where the dynamics of serum potassium is more stable. METHODS: Among 17,664 patients who started PD between January 1, 2007 and December 31, 2011 in a large US dialysis organization, we evaluated the association of serum potassium levels with all-cause and arrhythmia-related deaths across race/ethnicity using time-dependent Cox models with adjustments for demographics. We also used restricted cubic spline functions for serum potassium levels to explore non-linear associations. RESULTS: Baseline serum potassium levels were the highest among Hispanics (4.2 ± 0.7 mEq/L) and lowest among non-Hispanic blacks (4.0 ± 0.7 mEq/L). Among 2,949 deaths during the follow-up of median 2.2 (interquartile ranges 1.3-3.2) years, 683 (23%) were arrhythmia-related deaths. Overall, both hyperkalemia and hypokalemia (i.e., serum potassium levels >5.0 and <3.5 mEq/L, respectively) were associated with higher all-cause and arrhythmia-related mortality. In a stratified analysis according to race/ethnicity, the association of hypokalemia with all-cause and arrhythmia-related mortality was consistent with an attenuation for arrhythmia-related mortality in non-Hispanic blacks. Hyperkalemia was associated with all-cause and arrhythmia-related mortality in non-Hispanic whites and non-Hispanic blacks, but no association was observed in Hispanics. CONCLUSION: Among incident PD patients, hypokalemia was consistently associated with all-cause and arrhythmia-related deaths irrespective of race/ethnicity. However, while hyperkalemia was associated with both death outcomes in non-Hispanic blacks and whites, it was not associated with either death outcome in Hispanic patients. Further studies are needed to demonstrate whether different strategies should be followed for the management of serum potassium levels according to race/ethnicity.

Incidence, predictors and clinical management of hyperkalaemia in new users of mineralocorticoid receptor antagonists.

BACKGROUND: Concerns for hyperkalaemia limit the use of mineralocorticoid receptor antagonists (MRAs). The frequency of MRA-associated hyperkalaemia in real-world settings and the extent of subsequent MRA discontinuation are poorly quantified. METHODS AND RESULTS: Observational study including all Stockholm citizens initiating MRA therapy during 2007-2010. Hyperkalaemias were identified from all potassium (K+ ) measurements in healthcare. MRA treatment lengths and dosages were obtained from complete collection of pharmacy dispensations. We assessed the 1-year incidence and clinical hyperkalaemia predictors, and quantified drug prescription changes after an episode of hyperkalaemia. Overall, 13 726 new users of MRA were included, with median age of 73 years, 53% women and median plasma K+ of 3.9 mmol/L. Within a year, 18.5% experienced at least one detected hyperkalaemia (K+ > 5.0 mmol/L), the majority within the first 3 monthsnthsnthsnthsnths of therapy. As a comparison, hyperkalaemia was detected in 6.4% of propensity-matched new beta-blocker users. Chronic kidney disease (CKD), older age, male sex, heart failure, peripheral vascular disease, diabetes and concomitant use of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers and diuretics were associated with increased hyperkalaemia risk. After hyperkalaemia, 47% discontinued MRA and only 10% reduced the prescribed dose. Discontinuation rates were higher after moderate/severe (K+ > 5.5 mmol/L) and early in therapy (<3 months from initiation) hyperkalaemias. CKD participants carried the highest risk of MRA discontinuation in adjusted analyses. When MRA was discontinued, most patients (76%) were not reintroduced to therapy during the subsequent year. CONCLUSION: Among real-world adults initiating MRA therapy, hyperkalaemia was very common and frequently followed by therapy interruption, especially among participants with CKD.

Clinical and Economic Impact of Hyperkalemia in Patients with Chronic Kidney Disease and Heart Failure.

BACKGROUND: Hyperkalemia (HK) is a concern for patients with chronic kidney disease (CKD) and heart failure (HF), and for those receiving treatments that inhibit the renin-angiotensin-aldosterone system (RAASi). An analysis of 1.7 million medical records of patients in the United States revealed that among individuals with more than 2 potassium values during 2007 to 2012, HK was detected in 34.6% of patients with CKD and 30.0% of patients with HF. OBJECTIVE: To evaluate the association of HK and use of RAASi therapies at optimal and suboptimal doses in patients with CKD and/or HF with health care resource utilization and overall cost of care in a diverse cohort of commercially insured patients. METHODS: This retrospective cohort study was conducted using medical and pharmacy claims from multiple regional health plans. Qualifying patients were ≥ 18 years old, continuously enrolled for 6 months before and throughout the study period (January 1, 2014, to December 31, 2015) and had an ICD-9-CM or ICD-10-CM diagnosis code of CKD and/or HF. Health care resource utilization, including hospital visits, length of stay, office visits, and associated medical and pharmacy costs, were assessed according to the 3 cohorts (CKD alone, HF alone, and concomitant CKD and HF). For the 3 cohorts, the results were also compared between patients with and without HK and between patients with and without RAASi use at optimal and suboptimal doses. Generalized linear models were used to further examine the predictors of medical and overall costs. RESULTS: In this study, 15,999 patients met inclusion criteria. Among patients using RAASi therapy, 26.8% received the optimal dose. Optimal dosing of RAASi was associated with decreased median outpatient office visits (8, 10, and 15, respectively, for patients with CKD, HF, and both CKD and HF) compared with suboptimal dosing of RAASi (12, 15, and 23, respectively). Similarly, optimal dosing of RAASi was associated with decreased overall median medical costs ($2,092, $4,144, and $7,762, respectively, for patients with CKD, HF, and both CKD and HF) compared with suboptimal dosing of RAASi ($3,121, $8,289, and $12,749, respectively). Patients with CKD, HF, or both CKD and HF, all in combination with HK, had higher overall costs, compared with those without HK. CONCLUSIONS: The results of this real-world analysis suggest that HK and suboptimal dosing of RAASI were associated with a median increase in outpatient office visits as well as increased overall medical costs among patients with CKD and/or HF. This evaluation of median costs suggests effective HK management may potentially reduce costs in patients with CKD and/or HF, including those currently receiving RAASi therapy. DISCLOSURES: This study was conducted by Magellan Rx Management and funded by Relypsa. Brenner, Alvarez, and Oestreicher were employed by Relypsa during the development of this study and the writing of this manuscript. Polson, Lord, Kangethe, Speicher, and Farnum are employees of Magellan Rx Management, which received funding from Relypsa for conducting the retrospective study and writing the manuscript. Study concept and design were contributed by Lord, Polson, Brenner, Alvarez, and Oestreicher. Data collection and interpretation were performed by Polson and Kangethe, with assistance from Lord. The manuscript was written by Farnum, with assistance from Kangethe and Speicher and revised by all authors.

Characterization of Mineralocorticoid Receptor Antagonist Therapy Initiation in High-Risk Patients With Heart Failure.

BACKGROUND: Heart failure guidelines recommend routine monitoring of serum potassium, and renal function in patients treated with a mineralocorticoid receptor antagonist (MRA). How these recommendations are implemented in high-risk patients or according to setting of drug initiation is poorly characterized. METHODS AND RESULTS: We conducted a retrospective cohort study of Medicare beneficiaries linked to laboratory data in 10 states with prevalent heart failure as of July 1, 2011, and incident MRA use between May 1 and September 30, 2011. Outcomes included laboratory testing before MRA initiation and in the early (days 1-10) and extended (days 11-90) post-initiation periods, based on setting of drug initiation and the presence of renal insufficiency. Additional outcomes included abnormal laboratory results and adverse events proximate to MRA initiation. Of 10 443 Medicare beneficiaries with heart failure started on an MRA, 19.7% were initiated during a hospitalization. Appropriate follow-up laboratory testing across all time periods occurred in 25.2% of patients with inpatient initiation compared with 2.8% of patients begun as an outpatient. Patients with chronic kidney disease had higher rates of both hyperkalemia and acute kidney failure in the early (1.3% and 2.7%, respectively) and extended (5.6% and 9.8%, respectively) post-initiation periods compared with those without chronic kidney disease. CONCLUSIONS: Patients initiated on MRA therapy as an outpatient had extremely poor rates of guideline indicated follow-up laboratory monitoring after drug initiation. In particular, patients with chronic kidney disease are at high risk for adverse events after MRA initiation. Quality improvement initiatives focused on systems to improve appropriate laboratory monitoring are needed.

Impact of hyperkalaemia definition on incidence assessment: implications for epidemiological research based on a large cohort study in newly diagnosed heart failure patients in primary care.

BACKGROUND: Various definitions of hyperkalaemia have been used in clinical research, and data from routine clinical practice on its incidence are sparse. We aimed to establish the incidence of hyperkalaemia in patients with newly diagnosed heart failure in the UK general population using different definitions for the condition. METHODS: We conducted a large retrospective cohort study using data from The Health Improvement Network primary care database. Patients with newly diagnosed heart failure (N = 19,194) were identified and followed until the first occurrence of hyperkalaemia. Different serum potassium (K(+)) thresholds were evaluated as possible definitions for hyperkalaemia, and incidence rates (IRs) calculated using a final operational definition both overall and among patient sub-groups. RESULTS: IRs of hyperkalaemia ranged from 0.92-7.93 per 100 person-years according to the definition. Based on considerable differences in the serum K(+) normal range used between practices, 2176 (11.3 %) individuals were identified with a record of hyperkalaemia using our operational definition of a proportional increase of ≥10 % above the upper bound of the normal range: IR 2.90 per 100 person-years (95 % CI 2.78-3.02) over a mean follow-up of 3.91 years. Incidence rates were higher in older patients, and in those with diabetes or renal impairment. CONCLUSIONS: Hyperkalaemia is a common finding in heart failure patients in primary care, but its incidence can vary nearly ten-fold depending on its definition. Since assessment of hyperkalaemia risk is essential for therapeutic decision making in heart failure patients, this finding warrants consideration in future epidemiological studies.

Prevalence and prognostic significance of hyperkalemia in hospitalized patients with cirrhosis.

BACKGROUND: The prevalence and clinical significance of hyponatremia in cirrhotics have been well studied; however, there are limited data on hyperkalemia in cirrhotics. AIM: We evaluated the prevalence and prognostic significance of hyperkalemia in hospitalized patients with cirrhosis and developed a prognostic model incorporating potassium for prediction of liver-related death in these patients. METHODS: The training derivative cohort of patients was used for development of prognostic scores (Group A, n = 1160), which were validated in a large prospective cohort of cirrhotic patients. (Group B, n = 2681) of cirrhosis. RESULTS: Hyperkalemia was seen in 189 (14.1%) and 336 (12%) in Group A and Group B, respectively. Potassium showed a significant association that was direct with creatinine (P < 0.001) and urea (P < 0.001) and inverse with sodium (P < 0.001). Mortality was also significantly higher in patients with hyperkalemia (P = 0.0015, Hazard Ratio (HR) 1.3, 95% confidence interval 1.11-1.57). Combination of all these parameters into a single value predictor, that is, renal dysfunction index predicted mortality better than the individual components. Combining renal dysfunction index with other known prognostic markers (i.e. serum bilirubin, INR, albumin, hepatic encephalopathy, and ascites) in the "K" model predicted both short-term and long-term mortality with an excellent accuracy (Concordance-index 0.78 and 0.80 in training and validation cohorts, respectively). This was also superior to Model for End-stage Liver Disease, Model for End-stage liver disease sodium (MELDNa), and Child-Turcott-Pugh scores. CONCLUSIONS: Cirrhotics frequently have impaired potassium homeostasis, which has a prognostic significance. Serum potassium correlates directly with serum creatinine and urea and inversely with serum sodium. The model incorporating serum potassium developed from this study ("K"model) can predict death in advanced cirrhotics with an excellent accuracy.

Facility variation and predictors of serum potassium monitoring after initiation of a mineralocorticoid receptor antagonist in patients with heart failure.

BACKGROUND: Mineralocorticoid receptor antagonists (MRAs) have been shown to reduce morbidity and mortality in patients with heart failure (HF) with reduced ejection fraction but are associated with hyperkalemia. We sought to evaluate the frequency, variation, and predictors associated with serum potassium monitoring in patients with HF initiated on an MRA among facilities in the Veterans Affairs (VA) Health Care System. METHODS: We performed a retrospective cohort analysis of patients with HF across 133 Veterans Affairs facilities from 2003 to 2013 who were given a new prescription of an MRA. The primary outcome was the mean percentage of patients per facility with serum potassium monitoring within 14 days of MRA dispensing. Univariate and covariate analyses were performed to determine factors associated with monitoring. RESULTS: There were 142,880 patients identified with HF initiated on an MRA who met the study inclusion and exclusion criteria. The mean (SD) percentage of patients per facility with serum potassium monitoring within 14 days was 41.6% (standard deviation 8.0%; minimum 18.9%, maximum 56.7%). Facilities with a higher frequency of monitoring were associated with membership in the Council on Teaching Hospitals (n = 70, P < .0001), had academic affiliations (n = 100, P < .0001), and a higher annual volume of patients with HF (≥200 patients, P < .0001). CONCLUSIONS: In a large multicenter national sample of patients with HF receiving a new MRA prescription, the frequency of serum potassium monitoring was below recommended guidelines. Academic facilities and those with a higher volume of patients with HF were associated with an increased frequency of monitoring.

Serum potassium influencing interacting drugs: risk-modifying strategies also needed at discontinuation.

BACKGROUND: Although the discontinuation of a medication may have important clinical consequences, there is generally much less attention given to medication surveillance when a drug is stopped than when it is started. OBJECTIVE: To investigate the consequences on serum potassium levels of discontinuing a drug that increases the serum potassium level (PID↑) and a drug that decreases the serum potassium level (PLD↓) in patients taking both. METHODS: Patients who were hospitalized in the University Medical Centre Utrecht in 2004-2009 and were using both a PID↑ and a PLD↓ were included when one of these drugs was discontinued during hospitalization. Serum potassium levels measured before (potassium(1)) and after (potassium(2)) discontinuation were compared in patients who stopped the PLD↓ and in patients who stopped the PID↑. RESULTS: In the group of patients who stopped the PLD↓ (ie, continued the PID↑), mean serum potassium levels increased 0.19 mEq/L (range -0.9 to 1.8 mEq/L). After discontinuation of the PLD↓, serum potassium levels increased in 91 (59%) patients. Five patients (3.2%) developed hyperkalemia (potassium(2) >5.5 mEq/L). In the group of patients who stopped the PID↑ (ie, continued the PLD↓), mean serum potassium levels decreased 0.40 mEq/L (range -2.6 to 0.7 mEq/L). Serum potassium levels decreased in 61 (70%) patients after discontinuation of the PID↑. Fifteen patients (17%) developed hypokalemia (potassium(2) <3.5 mEq/L). Results were not influenced by length of stay, age, sex, renal function, and type of medication discontinued. CONCLUSIONS: The effects of serum potassium-influencing drugs need to be monitored not only after starting but also after stopping the medication. The same may hold true for the effects of other drugs. Clinical risk management should therefore focus on the risks not only when new medication is prescribed, but also when medication is stopped.

Frequency of laboratory measurement and hyperkalaemia in hospitalised patients using serum potassium concentration increasing drugs.

PURPOSE: Although, drug-drug interactions (DDIs) between potassium-increasing drugs (PIDs) are known risk factors for developing hyperkalaemia, not much is known about their risk and management strategies during hospitalisation. This study examines the frequency of serum potassium measurements and hyperkalaemia in hospitalised patients, based on the use of one or more PIDs, and the determinants thereof. METHODS: Adult patients hospitalised in the University Medical Centre Utrecht between 2006 and 2008 were included in this cross-sectional study. The frequency of serum potassium measurements and of hyperkalaemia were compared between patients using only one PID at a time (monotherapy group) and patients using two or more PIDs concomitantly (interaction group). The determinants studied were renal failure, diabetes mellitus, use of diuretics, type of DDI, start of the PIDs within the hospital versus continued home medication and medical speciality. RESULTS: Serum potassium was measured more frequently in the interaction group than in the monotherapy group [67 vs. 56%; relative risk (RR) 1.19, 95% confidence interval (CI) 1.14-1.24] and the risk of hyperkalaemia was also increased in the interaction group (9.9 vs. 5.9%, RR 1.7, 95% CI 1.3-2.1). The combination of potassium-sparing diuretics plus a potassium supplement, start of the PID within the hospital and hospitalisation in non-internal medicine departments was associated with higher relative risk estimates for hyperkalaemia. CONCLUSIONS: Among our patient cohort, even when physicians received a direct pop-up to monitor serum potassium levels when prescribing two PIDs concomitantly, serum potassium levels were not measured in 33% of patients, and 10% of patients developed hyperkalaemia. Improved management strategies and/or clinical decision-support systems are needed to decrease the frequency of hyperkalaemia following DDIs.

Serum potassium monitoring for users of ethinyl estradiol/drospirenone taking medications predisposing to hyperkalemia: physician compliance and survey of knowledge and attitudes.

PURPOSE: Yasmin-28 [ethinyl estradiol 0.03 mg/drospirenone 3 mg (EE/DRSP)] contains drospirenone, a progestin component that possesses antimineralocorticoid activity with a potassium-sparing diuretic effect similar to that in spironolactone. Product labeling recommends potassium monitoring in the first month of use for women concurrently receiving medication that may increase serum potassium. METHODS: We evaluated compliance with this recommendation by measuring monitoring around the date of oral contraceptive (OC) initiation in women who received EE/DRSP while being treated with medications predisposing to hyperkalemia and in similar women who received other OCs. Because preliminary analyses indicated incomplete compliance, we surveyed physicians who prescribed EE/DRSP to women receiving drugs predisposing to hyperkalemia on their knowledge and attitudes with regard to the recommendation. We conducted this study using data from the Ingenix Research Datamart, which includes insurance claims for reimbursement for medical services and prescription medications for approximately 8,000,000 members of a large nationally dispersed health plan. We used claims for pharmacy dispensings of prescription medications to identify all women aged 10-59 years old who initiated EE/DRSP or other OCs during the first 3 years of EE/DRSP availability (July 2001 to June 2004). The frequency of potassium monitoring was measured by identifying claims for serum potassium tests. We conducted a telephone survey of 58 physicians who had prescribed EE/DRSP up to June 2003 to women who received concomitant hyperkalemic drugs. RESULTS: Although potassium monitoring was generally more frequent among EE/DRSP initiators receiving concomitant hyperkalemic drugs than among other OC initiators receiving similar medications, only 40% of 466 EE/DRSP initiators with concurrent hyperkalemic treatment had potassium tests. More than 98% of surveyed physicians were aware of the potassium-sparing property of EE/DRSP. Compared with physicians whose patients had potassium tests, physicians of patients without such tests were more likely to disagree with the recommendation for users of angiotensin-converting enzyme inhibitors, angiotensin II receptor antagonists, heparin and nonsteroidal anti-inflammatory drugs. Patient barriers and health plan restrictions were other factors possibly contributing to noncompliance. CONCLUSION: This study demonstrates incomplete physician compliance with a labeling recommendation of potassium monitoring for initiators of EE/DRSP receiving concomitant therapy predisposing to hyperkalemia. The limited compliance was likely due to a combination of selective physician acceptance of the recommendations and specific patient and health plan barriers to testing.

[Life threatening hyperkalemia: the value of the electrocardiogram]. / Levensbedreigende hyperkaliëmie: de waarde van het elektrocardiogram.

In two men, aged 19 and 64, with chronic renal insufficiency and subacute symptoms of malaise and weakness of the leg muscles, broad QRS complexes were seen in the ECG. The younger patient developed an asystole and resuscitation was unsuccessful. His blood potassium level was found to be 8.3 mmol/l. The older patient recovered after administration of calcium gluconate. His blood potassium level was found to be 8.5 mmol/l. An 80-year-old woman who was taking various drugs because of heart failure also complained of muscle weakness. Her blood potassium level was 7.2 mmol/l and her ECG showed narrow complexes. She recovered without calcium gluconate after a change in medication. Hyperkalemia is a potentially life-threatening electrolyte disorder that may require immediate treatment. The changes in the ECG, especially widening of the QRS complexes, are the most important clues to the severity of the hyperkalemia. A treatment protocol based on ECG changes may reduce the mortality in these patients.

Potassium.

Potassium homeostasis is dependent on many physiologic and metabolic factors. Potassium level testing by the clinical laboratory can aid the emergency physician in planning treatment in suspected cases of potassium depletion or excess. Familiarization with indications for ordering tests of potassium level and correct interpretation of test results is essential for appropriate patient care.