Disorders of potassium homeostasis. Hypokalemia and hyperkalemia

Incidence, Risk Factors and Prognosis of Hypokalaemia in Patients with Normokalaemia at Hospital Admission

Background

Hypokalaemia (K+<3.5 mmol/L) is observed in 20% of hospitalised patients. Previous studies have often dealt with the symptoms, prevalence and risk factors in hospitalised patients. Very few studies have dealt with hospital-induced hypokalaemia. The aim was to determine the incidence, predisposing risk factors and prognosis of patients developing hypokalaemia after admission.

Materials and Methods

A prospective observational study was performed for two months. Patients with at least two potassium values after admission and normal K values at admission were considered for inclusion. Clinical features, diagnoses, laboratory reports and treatment details, including antibiotics, were noted.

Results

A total of 653 patients were studied; 138 (21.1%) developed hypokalaemia. Diabetes, ischaemic heart disease (IHD), heart failure, chronic kidney disease, hypertension, chronic liver disease and chronic obstructive pulmonary disease (COPD) were the most associated comorbidities. Urea, creatinine, transaminases and neutrophilia at admission differed significantly between those with and without hypokalaemia groups. Most patients developed mild hypokalaemia (78.2%). Hypokalaemia developed mostly on the second (22.4%) and third (24.6%) days of hospitalisation. Antibiotics were used in 60% of patients. The potassium values returned to normal within 2.5 ± 1.9 days. Three patients subsequently developed hyperkalaemia.

Conclusion

Patients admitted under general medicine mostly developed mild hypokalaemia, even if they had multiple risk factors for developing hypokalaemia. Inpatient hypokalaemia had an incidence of 21%. An overwhelming majority (~88%) had at least one risk factor. Hypokalaemia was not attributed to causing mortality in any patient.

Prediction prolonged mechanical ventilation in trauma patients of the intensive care unit according to initial medical factors: a machine learning approach

The goal of this study was to develop a predictive machine learning model to predict the risk of prolonged mechanical ventilation (PMV) in patients admitted to the intensive care unit (ICU), with a focus on laboratory and Arterial Blood Gas (ABG) data. This retrospective cohort study included ICU patients admitted to Rajaei Hospital in Shiraz between 2016 and March 20, 2022. All adult patients requiring mechanical ventilation and seeking ICU admission had their data analyzed. Six models were created in this study using five machine learning models (PMV more than 3, 5, 7, 10, 14, and 23 days). Patients' demographic characteristics, Apache II, laboratory information, ABG, and comorbidity were predictors. This study used Logistic regression (LR), artificial neural networks (ANN), support vector machines (SVM), random forest (RF), and C.5 decision tree (C.5 DT) to predict PMV. The study enrolled 1138 eligible patients, excluding brain-dead patients and those without mechanical ventilation or a tracheostomy. The model PMV > 14 days showed the best performance (Accuracy: 83.63-98.54). The essential ABG variables in our two optimal models (artificial neural network and decision tree) in the PMV > 14 models include FiO₂, paCO₂, and paO₂. This study provides evidence that machine learning methods outperform traditional methods and offer a perspective for achieving a consensus definition of PMV. It also introduces ABG and laboratory information as the two most important variables for predicting PMV. Therefore, there is significant value in deploying such models in clinical practice and making them accessible to clinicians to support their decision-making.

Incidence and Determinants of Piperacillin/Tazobactam-Associated Hypokalemia: A Retrospective Study

Piperacillin/tazobactam (TZP) is a commonly used antibiotic for treating moderate-to-severe infections because of its broad-spectrum activity and recommendation as an alternative to carbapenem. TZP-associated severe hypokalemia has been consistently reported; however, related studies are very rare. This study aimed to evaluate the incidence and risk factors of TZP-associated hypokalemia (TAH). A retrospective cohort study was conducted on hospitalized adult patients who received TZP from 1 January 2015 to 31 December 2017 at a tertiary teaching hospital. Of the 713 patients, 13.9% had TAH. As a result of multivariate logistic regression analysis, older age (OR 1.03, 95% CI: 1.02−1.05, p < 0.001), female sex (OR 1.88, 95% CI: 1.18−3.00, p = 0.008), longer duration of TZP therapy (OR 1.08, 95% CI: 1.04−1.13, p < 0.001), and higher TZP daily dose (OR 1.10, 95% CI: 1.01−1.20, p = 0.049) were independently associated with TAH. In contrast, higher baseline serum potassium level (OR 0.13, 95% CI: 0.07−0.26, p < 0.001) was related to lower TAH. Furthermore, hypokalemia mostly occurred in the early days of TZP therapy (median onset time: 4 days). Thus, close monitoring of serum potassium levels, especially upon therapy initiation, is essential to prevent TAH.

A Real-world Study on Prescription Pattern of Fosfomycin in Critical Care Patients

Background

This study presents a real-world scenario for prescription pattern, efficacy, and safety data on the current clinical use of intravenous fosfomycin in critically ill patients in Indian settings.

Patients and methods

This was a retrospective cohort study conducted for a period of 10 months among critically ill patients admitted to hospital's critical care unit. The primary objective of the study was to analyze the prescription pattern of intravenous fosfomycin, and the secondary objective was to evaluate the safety profile and patient outcomes.

Results

A total of 309 patients were enrolled, and they were diagnosed with bacteremia (45.3%), pneumonia (15.85%), septic shock (14.24%), and urinary tract infections (UTI) (13.91%). The average dose of fosfomycin given was 11.7 ± 4.06 gm/day. The average duration of the therapy was 4.85 ± 3.59 days with a median duration of 4 days. Fosfomycin was given at 8 hourly dosing frequency to maximum (45.6%) cases. Hypokalemia was the most observed adverse event. The overall survival was seen in 55% of patients.

Conclusion

Our data suggest that UTI, infection caused by Escherichia coli, and a daily dose of >12 g were associated with better clinical outcomes. The overall survival of critically ill patients receiving fosfomycin was 55%.

How to cite this article

Zirpe KG, Mehta Y, Pandit R, Pande R, Deshmukh AM, Patil S, et al. A Real-world Study on Prescription Pattern of Fosfomycin in Critical Care Patients. Indian J Crit Care Med 2021;25(9):1055–1058.

Electrolyte imbalance in infectious disease patients at King Abdulaziz Hospital, Jeddah

Objectives

Infectious diseases are the common cause of morbidity and mortality among humans. Electrolyte imbalance occurs frequently in patients with infectious diseases. This study aims to identify electrolyte imbalances in hospitalised patients with infectious diseases.

Methods

Two hundred and eighty-three patients with age mean 36.48 ± 18.86 years, consisting of 127 (53.4%) males, 111 (46.6%) females, enrolled in a retrospective cohort study carried out at the King Abdulaziz University Hospital, Jeddah, KSA from September to December 2020. All hospitalised patients with infectious diseases were included. Demographic data, comorbidity, and diagnosis were collected from patients’ sheets. Serum levels of electrolytes (chloride, potassium, sodium), urea, and creatinine were collected at admission (period 1), during hospital stay (period 2), and at discharge (period 3). Levels were compared during different periods.

Results

Most infectious diseases were viral infections (63.4%), while comorbidity was diabetes mellitus (7.1%). Serum chloride elevated from period 1 to period 3 (P = 0.046). Sodium elevated between period 1 and both period 2 and period 3 (P < 0.001). Urea decreased between period 1 and both period 2 (P = 0.018) and period 3 (P < 0.001). Creatinine decreased between period 1 and both period 2 and period 3 (P < 0.001) and between period 2 and period 3 (P < 0.001). Patients with decreased chloride and sodium levels were mostly in the 1st period, while those with decreased potassium levels were mostly in the period 2.

Conclusion

Prevalence of electrolyte imbalance in hospitalised patients with an infectious disease at the King Abdulaziz University Hospital, Jeddah was high, especially at admission and during the hospital stay.

Serum potassium variability is associated with increased mortality in a large cohort of hospitalized patients

BACKGROUND

Few studies have examined the role of serum potassium concentrations [K+] variability on clinical outcomes is still poorly investigated. Aim of our study was to analyze the association between serum potassium concentrations ([K+]) disorders, with focus on [K+] variability, and mortality in a large, unselected cohort of hospitalized patients.

METHODS

We performed a retrospective observational cohort study on the inpatient population admitted to Fondazione Policlinico Universitario A. Gemelli IRCCS between January 1, 2010 and December 31, 2014 with inclusion of adult patients with [K+] measurements ≥2. The outcome of interest was in-hospital mortality. The exposures of interest were [K+] fluctuations and hypo-hyperkalemia and mixed dyskalemia during hospital stay. [K+] variability was evaluated using the coefficient of variation (CV). Logistic regression models were fitted to obtain odds ratios (ORs) and 95% confidence intervals (CIs) for the association between the exposures of interest and in-hospital death.

RESULTS

Overall, 64,507 patients met our inclusion criteria. During a median follow-up of 8 days, 965 patients (1.5%) died. Multivariable adjusted logistic models suggested a higher risk for death in patients in the 3rd (OR 1.45, 95% CI 1.13, 1.88, p = 0.003) and 4th (OR 3.30, 95% CI 2.64, 4.16, p < 0.001) highest quartiles of [K+] CV compared with those in the lowest quartile with a significant linear trend across quartiles (p-trend <0.001) Results did not change after restricting the analyses to patients with normokaliemia (NK). All [K+] disorders were independently associated with an increased risk of in-hospital death compared with NK.

CONCLUSIONS

High [K+] variability is an independent risk factor of in-hospital mortality, even within the normal [K+] range.

Hypokalemia in Patients with COVID-19

BACKGROUND

Patients with COVID-19 experience multiple clinical conditions that may cause electrolyte imbalances. Hypokalemia is a concerning electrolyte disorder closely associated with severe complications. This study aimed to estimate prevalence, risk factors and outcome of hypokalemia in a cohort of patients with confirmed COVID-19.

METHODS

A retrospective analysis was conducted on 290 non-ICU admitted patients with COVID-19 at the tertiary teaching hospital of Modena, Italy, from February 16 to April 14, 2020.

RESULTS

Hypokalemia was detected in 119 out of 290 patients (41%) during hospitalization. Mean serum potassium was 3.1 ± 0.1 meq/L. The majority of patients (90.7%) patients experienced only a mild decrease in serum potassium level (3-3.4 mEq/L). Hypokalemia was associated with hypocalcemia, which was detected in 50% of subjects. Urine potassium-to-creatinine ratio, measured in a small number of patients (n = 45; 36.1%), revealed an increase of urinary potassium excretion in most cases (95.5%). Risk factors for hypokalemia were female sex (odds ratio (OR) 2.44; 95% CI 1.36-4.37; P 0.003) and diuretic therapy (OR 1.94, 95% CI 1.08-3.48; P 0.027). Hypokalemia, adjusted for sex, age and SOFA score, was not associated with ICU transfer (OR 0.52; 95% CI 0.228-1.212; P = 0.131), in-hospital mortality (OR, 0.47; 95% CI 0.170-1.324; P = 0.154) and composite outcome of ICU transfer or in-hospital mortality (OR 0.48; 95% CI 0.222-1.047; P = 0.065) in our cohort of patients.

CONCLUSIONS

Hypokalemia was a frequent disorder in subjects with COVID-19. Female sex and diuretic therapy were identified as risk factors for low serum potassium levels. Hypokalemia was unrelated to ICU transfer and death in this cohort of patients.

Dyselectrolytemia-management and implications in hemodialysis (Review)

Hemodialysis is a method for the renal replacement therapy followed by series of acute and chronic complications. Dyselectrolytemia appears in patients undergoing dialysis through mechanisms related to the chronic kidney disease and/or to the dialysis therapy and for this group of patients it is associated with an increase of morbidity and mortality. The dialysate has a standard composition, which can be modified according to the patient's characteristics. During hemodialysis patients are exposed to 18,000-36.000 litres of water/year, and the water purity along with the biochemical composition of the dialysate are essential. The individualization of the dialysis prescription is recommended for each patient and it has an important role in preventing the occurrence of dyselectrolyemia. The individualization of the treatment prescription according to the blood constants of each patient is the prerogative of the nephrologist and the association of the electrolyte imbalances with the patients cardiovascular mortality explains the importance of paying special attention to them.

The Association Between Variability in Electrolytes and the In-Hospital Mortality in Critically Ill Children in Pediatric Intensive Care Units

Objective: This study aimed to explore the association between the variability in electrolytes and the in-hospital mortality in critically ill children admitted into intensive care units (ICUs). Design: This is a retrospective case-control study. Setting and Participants: Total of 11,245 children have been admitted to ICUs of Children's Hospital of Zhejiang University from 2010 to 2018. Methods: The coefficient of variation (CV), standard deviation (SD), and variability independent of the mean (VIM) were calculated as variability indices. High variability was defined as having values in the highest quartile for each parameter. Age, sex, diagnoses of disease, and surgical treatment were adjusted in the multivariable-adjusted logistic regression model. Results: A total of 11,245 children were included, and 660 patients died in the hospital. The median (P25, P75) potassium, sodium, and chloride of all patients were 3.8 (3.58, 4.09), 136.83 (135.11, 138.60), and 108.67 (105.71, 111.17), respectively. U-shaped relationships between the mean, lowest, and highest levels of potassium, sodium, and chloride and the in-hospital mortality were observed. The lowest mortality was noted when serum potassium, sodium, and chloride were between ~3.5 and 5.0, 135 and 145, and 105 and 115 mmol/l, respectively. The areas under the curve (AUCs) of three indices of variability in electrolytes were larger than those of the mean and lowest levels of electrolytes in predicting the in-hospital mortality. In the multivariable-adjusted model, the odds ratios and 95% confidence interval (CI) of the in-hospital mortality were 3.14 (2.44-4.04) for one parameter, 5.85 (4.54-7.53) for two parameters, and 10.32 (7.81-13.64) for three parameters compared with subjects having no parameters of high variability measured as the CV. The results were consistent when the variability was determined using the SD and VIM (all P for trend <0.001). Consistent results were noted in various subgroup analyses. Conclusions: This study showed that individuals with higher variability of each parameter were related with higher risk of in-hospital mortality. There was a linear association between the number of high variability parameters and the in-hospital mortality. The variability of electrolytes might be a good predictor for in-hospital mortality of children in ICUs.

Quantification and classification of potassium and calcium disorders with the electrocardiogram: What do clinical studies, modeling, and reconstruction tell us?

Diseases caused by alterations of ionic concentrations are frequently observed challenges and play an important role in clinical practice. The clinically established method for the diagnosis of electrolyte concentration imbalance is blood tests. A rapid and non-invasive point-of-care method is yet needed. The electrocardiogram (ECG) could meet this need and becomes an established diagnostic tool allowing home monitoring of the electrolyte concentration also by wearable devices. In this review, we present the current state of potassium and calcium concentration monitoring using the ECG and summarize results from previous work. Selected clinical studies are presented, supporting or questioning the use of the ECG for the monitoring of electrolyte concentration imbalances. Differences in the findings from automatic monitoring studies are discussed, and current studies utilizing machine learning are presented demonstrating the potential of the deep learning approach. Furthermore, we demonstrate the potential of computational modeling approaches to gain insight into the mechanisms of relevant clinical findings and as a tool to obtain synthetic data for methodical improvements in monitoring approaches.

Pseudohyperkalemia caused by essential thrombocythemia in a patient with chronic renal failure: A case report

BACKGROUND

Hyperkalemia is one of the most common complications of chronic renal failure. Pseudohyperkalemia is caused by elevated levels of serum potassium in vitro and is usually accompanied by thrombocythemia. Although an elevated level of potassium is typically correlated with impaired renal function, pseudo-hyperkalemia has been rarely reported in patients with chronic renal failure. Here, we conducted a review of the literature to study the case of pseudo-hyperkalemia caused by the essential thrombocythemia in a patient with chronic renal failure.

CASE SUMMARY

A 73-year-old woman was admitted to our hospital with complaints of palpitation, dyspnea, and acratia for 2 d and a history of essential throm-bocythemia for 1 year. The routine blood test showed platelet count of 1460 × 10⁹/L, and biochemistry tests showed that the patient suffered from hyperkalemia (potassium: 7.50 mmol/L) and renal failure (estimated glomerular filtration rate: 8.88 mL/min). Initial treatment included medicines to lower her potassium-levels and hemodialysis. However, the therapy did not affect her serum potassium levels. Plasma potassium concentration measurements and a history of essential thrombocythemia established the diagnosis of pseudohyperkalemia. The treatments of the platelet disorder gradually normalized serum potassium levels; however, the treatments had to be discontinued later due to the severe leukopenia, and enhanced levels of serum potassium concentrations were observable in the patient. Since plasma sampling was not permitted, doctors had to use a diuretic just in case. Finally, the patient collapsed into unconsciousness and died due to multiple organ dysfunction and electrolyte disturbance.

CONCLUSION

We reviewed the literature and suggest that serum and plasma potassium values should both be measured for patients whose platelet counts exceed 500 × 10⁹/L to eliminate chances of pseudohyperkalemia, especially for those with chronic renal failure. An inappropriate treatment for pseudohyperkalemia can aggravate a patient's condition.

Acute Kidney Injury and Hyperkalemia With Precarious Electrocardiographic Changes Caused by Concurrent Use of Telmisartan and Diclofenac

A 70-year-old hypertensive man was prescribed telmisartan for control of blood pressure. He concurrently took over-the-counter diclofenac for back pain. Few days later, he presented to the casualty after syncopal episodes. He was found to have acute kidney injury and elevated potassium of 6.6 mmol/L with junctional bradycardia on electrocardiogram (ECG). Medical measures were instituted for hyperkalemia and sinus rhythm was restored, but peaked T waves were still present in the precordial leads. Hemodialysis was done, and antihypertensive therapy was changed on discharge.

Electrolyte Disorders and the Nervous System

PURPOSE OF REVIEW

This article provides an overview of the major electrolyte disorders and discusses in detail the homeostasis, etiologies, neurologic manifestations, and treatment of these disorders.

RECENT FINDINGS

The diagnosis and management of hyponatremia continue to evolve. Diagnostic accuracy is improved by assessing serum and urine osmolality as well as urinary sodium. Avoiding overcorrection of hyponatremia is crucial to avoid osmotic demyelination syndrome, although even careful correction can cause osmotic demyelination syndrome in patients who have other risk factors. The clinical presentation of osmotic demyelination syndrome has expanded, with many patients presenting with extrapontine myelinolysis in addition to central pontine myelinolysis.

SUMMARY

Electrolyte disorders often present with neurologic manifestations. Whereas disorders of some electrolytes, such as sodium, preferentially affect the central nervous system, disorders of others, such as potassium and calcium, have significant neuromuscular manifestations. An understanding of the pathophysiology of these disorders and recognition of these manifestations are crucial for the practicing neurologist as the symptoms are reversible with correct management.

A soft-chemistry approach to the synthesis of amorphous calcium ortho/pyrophosphate biomaterials of tunable composition

The development of amorphous phosphate-based materials is of major interest in the field of biomaterials science, and especially for bone substitution applications. In this context, we herein report the synthesis of gel-derived hydrated amorphous calcium/sodium ortho/pyrophosphate materials at ambient temperature and in water. For the first time, such materials have been obtained in a large range of tunable orthophosphate/pyrophosphate molar ratios. Multi-scale characterization was carried out thanks to various techniques, including advanced multinuclear solid state NMR. It allowed the quantification of each ionic/molecular species leading to a general formula for these materials: [(Ca²⁺_y Na⁺_z H⁺_3+x-2y-z)(PO₄^3-)_1-x(P₂O₇^4-)_x](H₂O)_u. Beyond this formula, the analyses suggest that these amorphous solids are formed by the aggregation of colloids and that surface water and sodium could play a role in the cohesion of the whole material. Although the full comprehension of mechanisms of formation and structure is still to be investigated in detail, the straightforward synthesis of these new amorphous materials opens up many perspectives in the field of materials for bone substitution and regeneration. STATEMENT OF SIGNIFICANCE: The metastability of amorphous phosphate-based materials with various chain length often improves their (bio)chemical reactivity. However, the control of the ratio of the different phosphate entities has not been yet described especially for small ions (pyrophosphate/orthophosphate) and using soft chemistry, whereas it opens the way for the tuning of enzyme- and/or pH-driven degradation and biological properties. Our study focuses on elaboration of amorphous gel-derived hydrated calcium/sodium ortho/pyrophosphate solids at 70 °C with a large range of orthophosphate/pyrophosphate ratios. Multi-scale characterization was carried out using various techniques such as advanced multinuclear SSNMR (³¹P, ²³Na, ¹H, ⁴³Ca). Analyses suggest that these solids are formed by colloids aggregation and that the location of mobile water and sodium could play a role in the material cohesion.

Influence of dyskalemia at admission and early dyskalemia correction on survival and cardiac events of critically ill patients

Objectives

Our objectives were (1) to characterize the distribution of serum potassium levels at ICU admission, (2) to examine the relationship between dyskalemia at ICU admission and occurrence of cardiac events, and (3) to study both the association between dyskalemia at ICU admission and dyskalemia correction by day 2 on 28-day mortality.

Design

Inception cohort study from the longitudinal prospective French multicenter OUTCOMEREA database (1999–2014)

Setting

22 French OUTCOMEREA network ICUs

Patients

Patients were classified into six groups according to their serum potassium level at admission: three groups of hypokalemia and three groups of hyperkalemia defined as serious hypokalemia [K+] < 2.5 and serious hyperkalemia [K+] > 7 mmol/L, moderate hypokalemia 2.5 ≤ [K+] < 3 mmol/L and moderate hyperkalemia 6 < [K+] ≤ 7 mmol/L, and mild hypokalemia 3 ≤ [K+] < 3.5 mmol/L and mild hyperkalemia 5 < [K+] ≤ 6 mmol/L. We sorted evolution at day 2 of dyskalemia into three categories: balanced, not-balanced, and overbalanced.

Intervention

None

Measurements and main results

Of 12,090 patients, 2108 (17.4%) had hypokalemia and 1445 (12%) had hyperkalemia.

Prognostic impact of dyskalemia and its correction was assessed using multivariate Cox models. After adjustment, hypokalemia and hyperkalemia were independently associated with a greater risk of 28-day mortality. Mild hyperkalemic patients had the highest mortality (hazard ratio (HR) 1.29, 95% confidence interval (CI) [1.13–1.47], p < 0.001). Adjusted 28-day mortality was higher if serum potassium level was not-balanced at day 2 (aHR = 1.51, 95% CI [1.30–1.76], p < 0.0001) and numerically higher but not significantly different if serum potassium level was overbalanced at day 2 (aHR = 1.157, 95% CI [0.84–1.60], p = 0.38). Occurrence of cardiac events was evaluated by logistic regression. Except for patients with serious hypokalemia at admission, the depth of dyskalemia was associated with increased risk of cardiac events.

Conclusions

Dyskalemia is common at ICU admission and associated with increased mortality. Occurrence of cardiac events increased with dyskalemia depth. A correction of serum potassium level by day 2 was associated with improved prognosis.

Severe Hyperkalemia Immediately After Birth

BACKGROUND Hyperkalemia is an important cause of arrhythmias and a medical emergency that requires urgent treatment. The etiology is usually multifactorial. It is most frequently caused by impaired potassium secretion, followed by transcellular potassium shifts and an increased potassium load. CASE REPORT A male newborn developed monomorphic ventricular tachycardia 2 hours after birth. He was born in the 35th week of gestation by urgent C-section following placental abruption. Laboratory results showed hemolytic anemia (Hb 99 g/L, Hct 0.31) with increased bilirubin levels and reticulocytosis, thrombocytopenia (39×10⁹/L), hypoglycemia (0.8 mmol/L), and severe hyperkalemia (9.8 mmol/L). Umbilical artery blood gas analysis showed hypoxemia with acidosis (pO₂ 3.8 kPa, pH 7.21, pCO₂ 7.84 kPa, HCO₃ 23.3 mmol/L, BE -5 mmol/L). Creatinine (102 µmol/L) and urea (9.8 mmol/L) were mildly elevated. Inflammatory markers were also increased (CRP 26 mg/L, blood leukocyte count 24×10⁹/L). Early-onset sepsis, caused by Candida albicans, was confirmed approximately 24 hours after birth. Non-invasive ventilation with 35-40% O₂ was necessary due to transient tachypnea. The neonate received a transfusion of packed red blood cells, a 10% glucose infusion, and empirical antibiotic therapy. Hyperkalemia accompanied by arrhythmias was treated with calcium gluconate, insulin, Sorbisterit enema, and, finally, by exchange transfusion. CONCLUSIONS We report a case of severe hyperkalemia in a newborn immediately after birth. Making a decision as early as possible regarding exchange transfusion is essential in patients with hyperkalemia with electrocardiogram changes and hemodynamic instability.

Current clinical use of intravenous fosfomycin in ICU patients in two European countries

PURPOSE

In Europe, intravenous fosfomycin (IV) is used particularly in difficult-to-treat or complex infections, caused by both Gram-positive and Gram-negative pathogens including multidrug-resistant strains. Here, we investigated the efficacy and safety of intravenous fosfomycin under real-life conditions.

METHODS

Prospective, multi-center, and non-interventional study in patients with bacterial infections from 20 intensive care units (ICU) in Germany and Austria (NCT01173575).

RESULTS

Overall, 209 patients were included (77 females, 132 males, mean age: 59 ± 16 years), 194 of which were treated in intensive care (APACHE II score at the beginning of fosfomycin therapy: 23 ± 8). Main indications (± bacteremia or sepsis) were infections of the CNS (21.5%), community- (CAP) and hospital-acquired pneumonia (HAP)/ventilator-associated pneumonia (VAP, 15.3%), bone and joint infections (BJI, 11%), abdominal infections (11%), and bacteremia (10.5%). Most frequently identified pathogens were S. aureus (22.3%), S. epidermidis (14.2%), Enterococcus spp. (10.8%), E. coli (12.3%) and Klebsiella spp. (7.7%). At least one multidrug-resistant (MDR) pathogen was isolated from 51 patients (24.4%). Fosfomycin was administered with an average daily dose of 13.7 ± 3.5 g over 12.4 ± 8.6 days, almost exclusively (99%) in combination with other antibiotics. The overall clinical success was favorable in 81.3% (148/182) of cases, and in 84.8% (39/46) of patients with ≥ 1 MDR pathogen. Noteworthy, 16.3% (34/209) of patients developed at least one, in the majority of cases non-serious, adverse drug reaction during fosfomycin therapy.

CONCLUSION

Our data suggest that IV fosfomycin is an effective and safe combination partner for the treatment of a broad spectrum of severe bacterial infections in critically ill patients.

Acoustofluidic Micromixing Enabled Hybrid Integrated Colorimetric Sensing, for Rapid Point-of-Care Measurement of Salivary Potassium

The integration of microfluidics with advanced biosensor technologies offers tremendous advantages such as smaller sample volume requirement and precise handling of samples and reagents, for developing affordable point-of-care testing methodologies that could be used in hospitals for monitoring patients. However, the success and popularity of point-of-care diagnosis lies with the generation of instantaneous and reliable results through in situ tests conducted in a painless, non-invasive manner. This work presents the development of a simple, hybrid integrated optical microfluidic biosensor for rapid detection of analytes in test samples. The proposed biosensor works on the principle of colorimetric optical absorption, wherein samples mixed with suitable chromogenic substrates induce a color change dependent upon the analyte concentration that could then be detected by the absorbance of light in its path length. This optical detection scheme has been hybrid integrated with an acoustofluidic micromixing unit to enable uniform mixing of fluids within the device. As a proof-of-concept, we have demonstrated the real-time application of our biosensor format for the detection of potassium in whole saliva samples. The results show that our lab-on-a-chip technology could provide a useful strategy in biomedical diagnoses for rapid analyte detection towards clinical point-of-care testing applications.

Hypokalaemia Re-Visited: A Case Series

Hypokalaemia is a relatively common biochemical abnormality found at the emergency department. Sequential changes in the electrocardiogram occur as the serum potassium is lowered. Correction of hypokalaemia can be life-saving. It is essential for physicians to be able to recognise these changes and initiate prompt replacement when necessary. We present a case series of patients presenting to the emergency department with symptomatic hypokalaemia and discuss the electrocardiographic manifestations and recognition of hypokalaemic changes.

Chest pain as a manifestation of hypokalemia in a pediatric patient

Patients presenting to the emergency department with chest pain are common and a cause of significant concern to patients and families and physicians alike. The causes of chest pain are myriad. These causes span diverse categories including cardiovascular, respiratory, abdominal and gastrointestinal, musculoskeletal, psychiatric, hematologic and oncologic, and neurologic Thull-Freedman (2010) [1]. These diverse etiologies present a diagnostic and management challenge to the ER physician who is tasked to minimize unnecessary diagnostics while not missing any significant disease. Multiple reviews have discussed the various etiologies of chest pain in the pediatric patient presenting to the ER but none of these recent reviews has included hypokalemia as a cause of chest pain Talner and Carboni (2000), Cava and Sayger (2004), Ringstrom and Freedman (2006), Foy and Filippone (2015), Yeh and Yeh (2015) [2-6]. Additionally, no reviews of hypokalemia describe this condition presenting with chest pain (Mandal, 1997; Gennari, 2002; Medford-Davis and Rafique, 2014 [7-9]). This case report describes a pediatric patient who presents with chest pain that was attributed to hypokalemia. This report attempts to make practitioners aware that hypokalemia may present with chest pain and to encourage ER providers to include this in the differential diagnosis.

Racial and Ethnic Differences in Mortality Associated with Serum Potassium in a Large Hemodialysis Cohort

BACKGROUND

Hyperkalemia is observed in chronic kidney disease patients and may be a risk factor for life-threatening arrhythmias and death. Race/ethnicity may be important modifiers of the potassium-mortality relationship in maintenance hemodialysis (MHD) patients given that potassium intake and excretion vary among minorities.

METHODS

We examined racial/ethnic differences in baseline serum potassium levels and all-cause and cardiovascular mortality using Cox proportional hazard models and restricted cubic splines in a cohort of 102,241 incident MHD patients. Serum potassium was categorized into 6 groups: ≤3.6, >3.6 to ≤4.0, >4.0 to ≤4.5 (reference), >4.5 to ≤5.0, >5.0 to ≤5.5, and >5.5 mEq/L. Models were adjusted for case-mix and malnutrition-inflammation cachexia syndrome (MICS) covariates.

RESULTS

The cohort was composed of 50% whites, 34% African-Americans, and 16% Hispanics. Hispanics tended to have the highest baseline serum potassium levels (mean ± SD: 4.58 ± 0.55 mEq/L). Patients in our cohort were followed for a median of 1.3 years (interquartile range 0.6-2.5). In our cohort, associations between higher potassium (>5.5 mEq/L) and higher mortality risk were observed in African-American and whites, but not Hispanic patients in models adjusted for case-mix and MICS covariates. While in Hispanics only, lower serum potassium (<3.6 mEq/L) levels were associated with higher mortality risk. Similar trends were observed for cardiovascular mortality.

CONCLUSIONS

Higher potassium levels were associated with higher mortality risk in white and African-American MHD patients, whereas lower potassium levels were associated with higher death risk in Hispanics. Further studies are needed to determine the underlying mechanisms for the differential association between potassium and mortality across race/ethnicity.

Hypokalaemia: Addressing human factors and improving education around prescription and administration of Intravenous(IV) Potassium infusion in Trauma and Orthopaedics

A high incidence of hypokalaemia was noted in Trauma and Orthopaedics of Ninewells Hospital. We sought to establish the reason behind this and implemented three PDSA cycles via questionnaires to 30 ward staff, both doctors and nurses over a 1 week period in December, February and July 2016. Key baseline measures include availability of IV fluids with 40mmol potassium on the wards, confidence prescribing or administering IV fluids with 40mmol potassium, necessity for cardiac monitoring during slow IV potassium replacement and recognition of confusion and learning need in this area. Interventions made include awareness and education session, departmental guideline, improving stock of IV fluids and hypokalaemia management pathway for mild, moderate and severe hypokalaemia. Post-intervention results showed 70% from 33% who said 40mmol IV potassium was available, 87% from 67% were confident prescribing or administering IV potassium and 70% from 27% were aware that cardiac monitoring was not necessary.

Agreement Between Serum Assays Performed in ED Point-of-Care and Hospital Central Laboratories

INTRODUCTION

Point-of-care (POC) testing allows for more time-sensitive diagnosis and treatment in the emergency department (ED) than sending blood samples to the hospital central laboratory (CL). However, many ED patients have blood sent to both, either out of clinical custom, or because clinicians do not trust the POC values. The objective of this study was to examine the level of agreement between POC and CL values in a large cohort of ED patients.

METHODS

In an urban, Level I ED that sees approximately 120,000 patients/year, all patients seen between March 1, 2013, and October 1, 2014, who had blood sent to POC and CL labs had levels of agreement measured between serum sodium, potassium, blood urea nitrogen (BUN), creatinine, and hematocrit. We extracted data from the hospital's clinical information system, and analyzed agreement with the use of Bland-Altman plots, defining both 95% confidence intervals (CIs) and more conservative CIs based on clinical judgment.

RESULTS

Out of 163,661 patients seen during the study period, 14,567 had blood samples sent both for POC and CL analysis. Using clinical criteria, the levels of agreement for sodium were 98.6% (within 5mg/dL), for potassium 90.7% (0.5 mmol/L), for BUN 89.0% (within 5 mg/dL), for creatinine 94.5% (within 0.3 mg/dL), for hematocrit 96.5% (within 5 g/dL).

CONCLUSION

Agreement between POC and CL values is excellent. Restricting the analysis to clinically important levels of agreement continues to show a high level of agreement. The data suggest that sending a serum sample to the hospital CL for duplicate assays is unnecessary. This may result in substantial savings and shorter ED lengths of stay.

Neurological Complications of Renal Disease

Neurological manifestations related to electrolyte disorders, drug toxicity, and uremia are common in chronic kidney disease (CKD). Seizures and coma are frequent complications of acute renal insufficiency (uremia), whereas peripheral neuropathy and encephalopathy, observed in progressive uremia, are terminal events. Failure to excrete metabolic products causes their accumulation and can lead to severe intoxication. Clinically, the signs and symptoms of uremia can vary widely, depending on the biological characteristics of the patient, the specific type of renal disease, and the time of the uremic intoxication. CKD is an increasing problem worldwide and is now being recognized as a global health burden particularly for cardiovascular and cerebrovascular ischemic events. Despite improvements in the medical management of advanced CKD, including dialysis and transplantation, patients manifest a number of symptoms that neurologists are often confronted with. Appropriate drug dosing, awareness of potential side effects of medications, prompt diagnosis, and treatment are essential in preventing neurological long-term morbidity and mortality.

Daily Laboratory Monitoring is of Poor Health Care Value in Adolescents Acutely Hospitalized for Eating Disorders

PURPOSE

This study investigates how the clinical practice guideline-recommended laboratory monitoring for refeeding syndrome impacts management and outcomes of adolescents with eating disorders hospitalized for acute medical stabilization and examines the value of laboratory monitoring (defined as the patient health outcomes achieved per dollar spent).

METHODS

A retrospective chart review of medical admissions in a children's hospital between October 2010 and February 2014 was performed. Encounters were identified using International Classification of Diseases, Ninth Revision codes of eating disorders as primary or secondary diagnoses. Exclusion criteria included systemic diseases associated with significant electrolyte abnormalities. Chart abstraction was performed using a predetermined form. Costs were estimated by converting hospital-fixed Medicaid charges using a statewide cost-to-charge ratio.

RESULTS

Of the 196 patient encounters, there were no cases of refeeding syndrome. A total of 3,960 key recommended laboratories were obtained; 1.9% were below normal range and .05% were critical values. Of these, .28% resulted in supplementation; none were associated with a change in inpatient management. Total laboratory costs were $269,250.85; the calculated health care value of this monitoring is 1.04 × 10(-8) differential outcomes per dollar spent.

CONCLUSIONS

This study provides evidence to suggest that daily laboratory monitoring for refeeding syndrome is a poor health care value in the management of adolescents hospitalized for acute medical stabilization with eating disorders. This initial analysis suggests that starting at a relatively low caloric level and advancing nutrition slowly may negate the need for daily laboratory assessment, which may have important implications for current guidelines.

Developing strategies for predicting hyperkalemia in potassium-increasing drug-drug interactions

OBJECTIVE

To compare different strategies predicting hyperkalemia (serum potassium level ≥5.5 mEq/l) in hospitalized patients for whom medications triggering potassium-increasing drug-drug interactions (DDIs) were ordered.

MATERIALS AND METHODS

We investigated 5 strategies that combined prediction triggered at onset of DDI versus continuous monitoring and taking into account an increasing number of patient parameters. The considered patient parameters were identified using generalized additive models, and the thresholds of the prediction strategies were calculated by applying Youden's J statistic to receiver operation characteristic curves. Half of the data served as the calibration set, half as the validation set.

RESULTS

We identified 132 incidences of hyperkalemia induced by 8413 potentially severe potassium-increasing DDIs among 76 467 patients. The positive predictive value (PPV) of those strategies predicting hyperkalemia at the onset of DDI ranged from 1.79% (undifferentiated anticipation of hyperkalemia due to the DDI) to 3.02% (additionally considering the baseline serum potassium) and 3.10% (including further patient parameters). Continuous monitoring significantly increased the PPV to 8.25% (considering the current serum potassium) and 9.34% (additional patient parameters).

CONCLUSION

Continuous monitoring of the risk for hyperkalemia based on current potassium level shows a better predictive power than predictions triggered at the onset of DDI. This contrasts with efforts to improve DDI alerts by taking into account more patient parameters at the time of ordering.

Improvement of surface ECG recording in adult zebrafish reveals that the value of this model exceeds our expectation

The adult zebrafish has been used to model the electrocardiogram (ECG) for human cardiovascular studies. Nonetheless huge variations are observed among studies probably because of the lack of a reliable and reproducible recording method. In our study, an adult zebrafish surface ECG recording technique was improved using a multi-electrode method and by pre-opening the pericardial sac. A convenient ECG data analysis method without wavelet transform was also established. Intraperitoneal injection of KCl in zebrafish induced an arrhythmia similar to that of humans, and the arrhythmia was partially rescued by calcium gluconate. Amputation and cryoinjury of the zebrafish heart induced ST segment depression and affected QRS duration after injury. Only cryoinjury decelerated the heart rate. Different changes were also observed in the QT interval during heart regeneration in these two injury models. We also characterized the electrocardiophysiology of breakdance zebrafish mutant with a prolonged QT interval, that has not been well described in previous studies. Our study provided a reliable and reproducible means to record zebrafish ECG and analyse data. The detailed characterization of the cardiac electrophysiology of zebrafish and its mutant revealed that the potential of the zebrafish in modeling the human cardiovascular system exceeds expectations.

Evaluation of an Intravenous Potassium Dosing Algorithm for Hypokalemic Critically Ill Patients

PURPOSE

The intent of this study was to evaluate the safety and efficacy of an intravenous (IV) potassium (K) dosing algorithm for hypokalemic critically ill trauma patients.

METHODS

Adult patients, admitted to the trauma intensive care unit from June 2010 to October 2012 and who received IV K therapy according to a standardized dosing algorithm, were retrospectively evaluated. Patients who received IV K during resuscitation or following initiation of nutrition therapy, IV fluids containing >20 mEq/L of potassium, or medications known to alter K homeostasis or those with an arterial pH change >0.1, diarrhea, hypomagnesemia, renal impairment, or morbid obesity were excluded.

RESULTS

In total, 715 patients were reviewed to obtain 100 evaluable patients. Serum K for patients with mild depletion (serum K, 3.5-3.9 mEq/L, n = 74) remained unchanged at 0.0 ± 0.3 mEq/L ( P = ns) following 46 ± 8 mEq. Serum K increased by 0.4 ± 0.3 mEq/L ( P = .001) following 78 ± 18 mEq during moderate depletion (serum K, 3-3.4 mEq/L). None of the patients experienced hyperkalemia (serum K, >5.2 mEq/L) postinfusion. The presence of traumatic brain injury (TBI) blunted the response to IV K for mild K depletion as only 26% had an increase in serum K compared with 55% of patients without TBI ( P = .025).

CONCLUSIONS

The Nutrition Support Service-guided IV K dosing algorithm was safe for patients with mild and moderate hypokalemia and efficacious for those with moderate hypokalemia. Further study in patients with severe hypokalemia (serum K, <3 mEq/L) is warranted.

The predicting ability of serum potassium to assess the duration of mechanical ventilation in critically ill patients

Background:

No previous study has been done to evaluate the admission serum potassium level as a predictor of morbidity or need for mechanical ventilation. The aim of this study is to determine the predictive ability of serum potassium on admission, in critically ill trauma patients, and to evaluate the relation of the potassium level to organ failure, length of stay, ventilator need, and duration of mechanical ventilation.

Materials and Methods:

A prospective, observational study was done on 100 patients >16 years old, admitted to the Medical-Surgical Intensive Care Units (ICU), for over one year. Patients were classified into Group A: Patients who required equal or less than five days of mechanical ventilation and Group B: Patients who required more than five days of mechanical ventilation. The total serum potassium concentrations were measured and the Sequential Organ Failure Assessment (SOFA) score was recorded at the time of admission to the ICU, when connected to the ventilator, and then at the time of weaning from the ventilator.

Results:

There was no significant difference between the Serum K concentrations between the two groups, on admission. However, there were significant difference between the Serum K concentrations at times of receiving and weaning from mechanical ventilation (MV) between the two groups. We found the best cut-off point of 3.45 for serum potassium concentration, to predict the need for longer duration of MV.

Conclusion:

Development of hypokalemia during an ICU stay is associated with the need for mechanical ventilation. Monitoring of the serum potassium levels may be a good prognostic factor for the requirement of mechanical ventilation.

Effect of potassium present in stratum corneum during non-invasive measurement of potassium in human subjects using reverse iontophoresis

PURPOSE

Reverse iontophoresis (RI) is one of the potential techniques used to monitor the concentration of various analytes in body fluids non-invasively. Transdermal extraction of potassium is investigated using RI. In the present work, the effect of potassium on stratum corneum (SC) during RI, feasibility of RI for continuous monitoring of potassium, and use of potassium as internal standard in RI, are investigated.

METHODS

Tape stripping experiment is carried out to find potassium concentration in SC. RI is carried out continuously for 180 min without passive diffusion and after passive diffusion for 60 min. Skin impedance measurements are done at 20 Hz and 20 kHz.

RESULTS

Potassium is found to be in the range 300-650 nmol/cm(2) on SC by tape stripping experiment. Correlation coefficient between blood potassium and extracted potassium through RI after passive diffusion (R(2) = 0.5870) is more than without passive diffusion (R(2) = 0.5117). The skin impedance measurement shows that RI has more effect on SC than superficial layer of SC during RI.

CONCLUSION

The present investigations conclude that it is possible to monitor potassium continuously through RI and using potassium as internal standard in RI.

The relationship between serum potassium, potassium variability and in-hospital mortality in critically ill patients and a before-after analysis on the impact of computer-assisted potassium control

Introduction

The relationship between potassium regulation and outcome is not known. Our first aim in the present study was to determine the relationship between potassium level and variability in (ICU) stay and outcome. The second aim was to evaluate the impact of a computer-assisted potassium regulation protocol.

Methods

We performed a retrospective before-after study including all patients >15 years of age admitted for more than 24 hours to the ICU of our university teaching hospital between 2002 and 2011. Potassium control was fully integrated with computerized glucose control (glucose and potassium regulation program for intensive care patients (GRIP-II)). The potassium metrics that we determined included mean potassium, potassium variability (defined as the standard deviation of all potassium levels) and percentage of ICU time below and above the reference range (3.5 through 5.0 mmol/L). These metrics were determined for the first ICU day (early phase) and the subsequent ICU days (late phase; that is, day 2 to day 7). We also compared potassium metrics and in-hospital mortality before and after GRIP-II was implemented in 2006.

Results

Of all 22,347 ICU admissions, 10,451 (47%) patients were included. A total of 206,987 potassium measurements were performed in these patients. Glucose was regulated by GRIP-II in 4,664 (45%) patients. The overall in-hospital mortality was 22%. There was a U-shaped relationship between the potassium level and in-hospital mortality (P <0.001). Moreover, potassium variability was independently associated with outcome. After implementation of GRIP-II, in the late phase the time below 3.5 mmol/L decreased from 9.2% to 3.9% and the time above 5.0 mmol/L decreased from 6.1% to 5.2%, and potassium variability decreased from 0.31 to 0.26 mmol/L (all P <0.001). The overall decrease in in-hospital mortality from 23.3% before introduction of GRIP-II to 19.9% afterward (P <0.001) was not related to a specific potassium subgroup.

Conclusions

Hypokalemia, hyperkalemia and potassium variability were independently associated with increased mortality. Computerized potassium control clearly resulted in improved potassium metrics.

Hypokalemia in acute medical patients: risk factors and prognosis

OBJECTIVE

Hypokalemia is one of the most common electrolyte disorders in hospitalized patients. It is associated with a high mortality rate among patients with cardiovascular disease. Whether hypokalemia confers a similar risk in an unselected hospitalized population is not well established.

METHODS

We conducted a prospective cohort study involving all first-time admissions (n = 11,988) to the Acute Medical Department at Odense University Hospital linking potassium level at admission with registry data on patient characteristics, laboratory data, redeemed prescriptions, and time of death for the period from August 2009 to August 2011. We estimated hazard ratios for all-cause mortality within 0 to 7 days and 8 to 30 days after admission, comparing patients with hypokalemia at admission (plasma [K(+)] level <3.4 mmol/L) with patients with eukalemia at admission ([K(+)] level of 3.4-3.8 mmol/L).

RESULTS

Hypokalemia occurred in 16.8% of first-time admissions (n = 2011). It was associated with an adjusted hazard ratio [HR] of 1.34 (95% confidence interval [CI], 0.98-1.85) for 7-day mortality and 1.56 (95% CI, 1.18-3.06) for 8- to 30-day mortality. Among patients with more severe hypokalemia (plasma [K(+)] <2.9 mmol/L), the adjusted HR was 2.17 (95% CI, 1.34-3.49) for 7-day mortality and 1.90 (95% CI, 1.18-3.06) for 8- to 30-day mortality. Prognostic factors for both 7-day and 8- to 30-day mortality among hypokalemic patients were increasing age and Charlson Comorbidity Index, whereas there was no prognostic effect of current diuretic or beta-agonist use.

CONCLUSIONS

In a mixed population of hospitalized medical patients, hypokalemia is common, and plasma [K(+)] <2.9 mmol/L is associated with increased 7-day and 8- to 30-day mortality.

Characterization of structure and function of ZS-9, a K+ selective ion trap

Hyperkalemia, a condition in which serum potassium ions (K+) exceed 5.0 mmol/L, is a common electrolyte disorder associated with substantial morbidity. Current methods of managing hyperkalemia, including organic polymer resins such as sodium polystyrene sulfonate (SPS), are poorly tolerated and/or not effective. Sodium zirconium cyclosilicate (ZS-9) is under clinical development as an orally administered, non-absorbed, novel, inorganic microporous zirconium silicate compound that selectively removes excess K+ in vivo. The development, structure and ion exchange properties of ZS-9 and its hypothesized mechanism of action are described. Based on calculation of the interatomic distances between the atoms forming the ZS-9 micropores, the size of the pore opening was determined to be ∼ 3 Å (∼ diameter of unhydrated K+). Unlike nonspecific organic polymer resins like SPS, the ZS-9 K+ exchange capacity (KEC) was unaffected by the presence of calcium (Ca2+) or magnesium ions (Mg2+) and showed>25-fold selectivity for K+ over either Ca2+ or Mg2+. Conversely, the selectivity of SPS for K+ was only 0.2-0.3 times its selectivity for Ca2+ or Mg2+in mixed ionic media. It is hypothesized that the high K+ specificity of ZS-9 is attributable to the chemical composition and diameter of the micropores, which possibly act in an analogous manner to the selectivity filter utilized by physiologic K+ channels. This hypothesized mechanism of action is supported by the multi-ion exchange studies. The effect of pH on the KEC of ZS-9 was tested in different media buffered to mimic different portions of the human gastrointestinal tract. Rapid K+ uptake was observed within 5 minutes - mainly in the simulated small intestinal and large intestinal fluids, an effect that was sustained for up to 1 hour. If approved, ZS-9 will represent a novel, first-in-class therapy for hyperkalemia with improved capacity, selectivity, and speed for entrapping K+ when compared to currently available options.

Extended release potassium salts overdose and endoscopic removal of a pharmacobezoar: A case report

BACKGROUND

Reported cases of potassium overdoses have shown that this condition could generate several morbidities, mainly related to cardiac dysrhythmias even with fatal outcomes in some cases. Potassium salts in extended release tablets could form pharmacobezoars if a large amount is ingested. In relation to the above, when the patient has a pharmacobezoar, clinical findings may be delayed and may persist. The techniques available for removal of a pharmacobezoar are whole bowel irrigation (WBI), endoscopy or in some surgery [1]. Endoscopy as a decontamination method has shown promising results.

CASE REPORT

A 42 year old woman, who intentionally ingested 100 tablets of extended release potassium chloride, 50 mg of clonazepam and an undisclosed amount of ethanol, presented with metabolic acidosis, hyperlactatemia and sinus tachycardia 2 h after ingestion. Gastric lavage and activated charcoal were applied initially, specific measures were not necessary. However, a transcutaneous pacemaker was placed. Because of her background, we considered a pharmacobezoar and an endoscopy were performed to remove 99 tablets of potassium that were isolated or forming concretions.

DISCUSSION

The readily available techniques to remove a pharmacobezoar are whole bowel irrigation (WBI) and endoscopy; nevertheless there is not a consensus about their relative merits. Our patient was treated by endoscopy because we found on the X-ray a conglomerate of radiopaque images suggesting a pharmacobezoar. In this case we did not have any adverse effect.

CONCLUSIONS

We consider that endoscopy could be an effective and safe method to remove a drug bezoar from the stomach in uncomplicated patients.

Hyperkalemia among hospitalized patients and association between duration of hyperkalemia and outcomes

INTRODUCTION

The aim of the study was to investigate predictors of mortality in patients hospitalized with hyperkalemia.

MATERIAL AND METHODS

Data among hospitalized patients with hyperkalemia (serum potassium ≥ 5.1 mEq/l) were collected. Patients with end-stage renal disease on dialysis were excluded.

RESULTS

Of 15,608 hospitalizations, 451 (2.9%) episodes of hyperkalemia occurred in 408 patients. In patients with hyperkalemia, chronic kidney disease, hypertension, diabetes, coronary artery disease and heart failure were common comorbidities. Acute kidney injury (AKI) and metabolic acidosis were common metabolic abnormalities, and 359 patients (88%) were on at least one drug associated with hyperkalemia. Mean duration to resolution of hyperkalemia was 12 ±9.9 h. Nonsteroidal anti-inflammatory drugs (HR = 1.59), highest potassium level (HR = 0.61), tissue necrosis (HR = 0.61), metabolic acidosis (HR = 0.77), and AKI (HR = 0.77) were significant independent determinants of duration prior to hyperkalemia resolution. Tissue necrosis (OR = 4.55), potassium supplementation (OR = 5.46), metabolic acidosis (OR = 4.84), use of calcium gluconate for treatment of hyperkalemia (OR = 4.62), AKI (OR = 3.89), and prolonged duration of hyperkalemia (OR = 1.06) were significant independent predictors of in-hospital mortality.

CONCLUSIONS

Tissue necrosis, potassium supplementation, metabolic acidosis, calcium gluconate for treatment of hyperkalemia, AKI and prolonged duration of hyperkalemia are independent predictors of in-hospital mortality.

Neurologic complications of electrolyte disturbances and acid-base balance

Electrolyte and acid-base disturbances are common occurrences in daily clinical practice. Although these abnormalities can be readily ascertained from routine laboratory findings, only specific clinical correlates may attest as to their significance. Among a wide phenotypic spectrum, acute electrolyte and acid-base disturbances may affect the peripheral nervous system as arreflexic weakness (hypermagnesemia, hyperkalemia, and hypophosphatemia), the central nervous system as epileptic encephalopathies (hypomagnesemia, dysnatremias, and hypocalcemia), or both as a mixture of encephalopathy and weakness or paresthesias (hypocalcemia, alkalosis). Disabling complications may develop not only when these derangements are overlooked and left untreated (e.g., visual loss from intracranial hypertension in respiratory or metabolic acidosis; quadriplegia with respiratory insufficiency in hypermagnesemia) but also when they are inappropriately managed (e.g., central pontine myelinolisis when rapidly correcting hyponatremia; cardiac arrhythmias when aggressively correcting hypo- or hyperkalemia). Therefore prompt identification of the specific neurometabolic syndromes is critical to correct the causative electrolyte or acid-base disturbances and prevent permanent central or peripheral nervous system injury. This chapter reviews the pathophysiology, clinical investigations, clinical phenotypes, and current management strategies in disorders resulting from alterations in the plasma concentration of sodium, potassium, calcium, magnesium, and phosphorus as well as from acidemia and alkalemia.

Calcium supplementation during sepsis exacerbates organ failure and mortality via calcium/calmodulin-dependent protein kinase kinase signaling

BACKGROUND

Calcium plays an essential role in nearly all cellular processes. As such, cellular and systemic calcium concentrations are tightly regulated. During sepsis, derangements in such tight regulation frequently occur, and treating hypocalcemia with parenteral calcium administration remains the current practice guideline.

OBJECTIVE

We investigated whether calcium administration worsens mortality and organ dysfunction using an experimental murine model of sepsis and explored the mechanistic role of the family of calcium/calmodulin-dependent protein kinases in mediating these physiological effects. To highlight the biological relevance of these observations, we conducted a translational study of the association between calcium administration, organ dysfunction, and mortality among a cohort of critically ill septic ICU patients.

DESIGN

Prospective, randomized controlled experimental murine study and observational clinical cohort analysis.

SETTING

University research laboratory and eight ICUs at a tertiary care center.

PATIENTS

A cohort of 870 septic ICU patients.

SUBJECTS

C57Bl/6 and CaMKK mice.

INTERVENTIONS

Mice underwent cecal ligation and puncture polymicrobial sepsis and were administered with calcium chloride (0.25 or 0.25 mg/kg) or normal saline.

MEASUREMENTS AND MAIN RESULTS

Administering calcium chloride to septic C57Bl/6 mice heightened systemic inflammation and vascular leak, exacerbated hepatic and renal dysfunction, and increased mortality. These events were significantly attenuated in CaMKK mice. In a risk-adjusted analysis of septic patients, calcium administration was associated with an increased risk of death, odds ratio 1.92 (95% CI, 1.00-3.68; p = 0.049), a significant increase in the risk of renal dysfunction, odds ratio 4.74 (95% CI, 2.48-9.08; p < 0.001), and a significant reduction in ventilator-free days, mean decrease 3.29 days (0.50-6.08 days; p = 0.02).

CONCLUSIONS

Derangements in calcium homeostasis occur during sepsis that is sensitive to calcium administration. This altered calcium signaling, transduced by the calmodulin-dependent protein kinase kinase cascade, mediates heightened inflammation and vascular leak that culminates in elevated organ dysfunction and mortality. In the clinical management of septic patients, calcium supplementation provides no benefit and may impose harm.

6-bromoisatin found in muricid mollusc extracts inhibits colon cancer cell proliferation and induces apoptosis, preventing early stage tumor formation in a colorectal cancer rodent model

Muricid molluscs are a natural source of brominated isatin with anticancer activity. The aim of this study was to examine the safety and efficacy of synthetic 6-bromoisatin for reducing the risk of early stage colorectal tumor formation. The purity of 6-bromoisatin was confirmed by ¹H NMR spectroscopy, then tested for in vitro and in vivo anticancer activity. A mouse model for colorectal cancer was utilized whereby colonic apoptosis and cell proliferation was measured 6 h after azoxymethane treatment by hematoxylin and immunohistochemical staining. Liver enzymes and other biochemistry parameters were measured in plasma and haematological assessment of the blood was conducted to assess potential toxic side-effects. 6-Bromoisatin inhibited proliferation of HT29 cells at IC₅₀ 223 μM (0.05 mg/mL) and induced apoptosis without increasing caspase 3/7 activity. In vivo 6-bromoisatin (0.05 mg/g) was found to significantly enhance the apoptotic index (p ≤ 0.001) and reduced cell proliferation (p ≤ 0.01) in the distal colon. There were no significant effects on mouse body weight, liver enzymes, biochemical factors or blood cells. However, 6-bromoisatin caused a decrease in the plasma level of potassium, suggesting a diuretic effect. In conclusion this study supports 6-bromoisatin in Muricidae extracts as a promising lead for prevention of colorectal cancer.

Hypokalemia and hyperkalemia in infants and children: pathophysiology and treatment

Potassium is the second most abundant cation in the body. About 98% of potassium is intracellular and that is particularly in the skeletal muscle. Electrical disturbances associated with disorders of potassium homeostasis are a function of both the extracellular and intracellular potassium concentrations. Clinical disorders of potassium homeostasis occur with some regularity, especially in hospitalized patients receiving many medications. This article will review the pathophysiology of potassium homeostasis, symptoms, causes, and treatment of hypo- and hyperkalemia.

Patient- and physician-related risk factors for hyperkalaemia in potassium-increasing drug-drug interactions

PURPOSE

Hyperkalaemia due to potassium-increasing drug-drug interactions (DDIs) is a clinically important adverse drug event. The purpose of this study was to identify patient- and physician-related risk factors for the development of hyperkalaemia.

METHODS

The risk for adult patients hospitalised in the University Hospital Zurich between 1 December 2009 and 31 December 2011 of developing hyperkalaemia was correlated with patient characteristics, number, type and duration of potassium-increasing DDIs and frequency of serum potassium monitoring.

RESULTS

The 76,467 patients included in this study were prescribed 8,413 potentially severe potassium-increasing DDIs. Patient-related characteristics associated with the development of hyperkalaemia were pulmonary allograft [relative risk (RR) 5.1; p < 0.0001), impaired renal function (RR 2.7; p < 0.0001), diabetes mellitus (RR 1.6; p = 0.002) and female gender (RR 1.5; p = 0.007). Risk factors associated with medication were number of concurrently administered potassium-increasing drugs (RR 3.3 per additional drug; p < 0.0001) and longer duration of the DDI (RR 4.9 for duration ≥6 days; p < 0.0001). Physician-related factors associated with the development of hyperkalaemia were undetermined or elevated serum potassium level before treatment initiation (RR 2.2; p < 0.001) and infrequent monitoring of serum potassium during a DDI (interval >48 h: RR 1.6; p < 0.01).

CONCLUSION

Strategies for reducing the risk of hyperkalaemia during potassium-increasing DDIs should consider both patient- and physician-related risk factors.

Potassium balances in maintenance hemodialysis

Potassium is abundant in the ICF compartment in the body and its excretion primarily depends on renal (about 90%), and to a lesser extent (about 10%) on colonic excretion. Total body potassium approximated to 50mmol/kg body weight and 2% of total body potassium is in the ECF compartment and 98% of it in the intracellular compartment.Dyskalemia is a frequent electrolyte imbalance observed among the maintenance hemodialysis patients. In case of hyperkalemia, it is frequently "a silent and a potential life threatening electrolyte imbalance" among patients with ESRD under maintenance hemodialysis. The prevalence of hyperkalemia in maintenance HD patients was reported to be about 8.7-10%. Mortality related to the hyperkalemia has been shown to be about 3.1/1,000 patient-years and about 24% of patients with HD required emergency hemodialysis due to severe hyperkalemia. In contrast to the hyperkalemia, much less attention has been paid to the hypokalemia in hemodialysis patients because of the low prevalence under maintenance hemodialysis patients. Severe hypokalemia in the hemodialysis patients usually was resulted from low potassium intake (malnutrition), chronic diarrhea, mineralocorticoid use, and imprudent use of K-exchange resins. Recently, the numbers of the new patients with advanced chronic kidney disease undergoing maintenance hemodialysis are tremendously increasing worldwide. However, the life expectancy of these patients is still much lower than that of the general population. The causes of excess mortality in these patients seem to various, but dyskalemia is a common cause among the patients with ESRD undergoing hemodialysis.