Electrolyte Changes Research Articles

Association of furosemide versus chlorothiazide exposures with serum sodium, potassium, and chloride among infants with bronchopulmonary dysplasia.

To examine the association of novel furosemide versus thiazide diuretic exposure with changes in serum sodium, potassium, and chloride levels among infants with grade 2/3 bronchopulmonary dysplasia (BPD). Retrospective cohort study of infants admitted to a level IV neonatal intensive care unit (NICU) with grade 2/3 BPD. We measured within-subject change in serum sodium, potassium, and chloride before and after diuretic initiation using multivariable regression to adjust for differences in dosing and clinical covariates. We identified 94 infants contributing 137 novel diuretic exposures. No significant difference was noted in the association between chlorothiazide versus furosemide and serum sodium, potassium, or chloride change in multivariable modeling. Changes in serum electrolytes were similar for chlorothiazide and furosemide, questioning the perception that chlorothiazide leads to less electrolyte derangement among preterm infants with grade 2/3 BPD.

Continuous lattice oxygen participation of NiFe stack anode for Sustainable water Splitting

Non-noble anode catalysts exhibit insufficient activity and stability for anion exchange membrane water electrolysis (AEMWE). Accordingly, we propose an electrolyte additive strategy involving NiFe-layered double hydroxide. In situ Raman spectroscopy and 18O isotope labeling experiments reveal that Fe ions in the electrolyte change the oxygen evolution reaction mechanism from adsorbate evolution to the lattice oxygen participation mechanism (LOM). These Fe ions continuously refill Fe vacancies owing to facile metal dissolution via the LOM. In a unit cell, we achieve an excellent cell voltage of 1.73 V and energy conversion efficiency (ECE) of 69.4 % at 3.0 A cm−2, meeting the target set by the U.S. Department of Energy (1.80 V and 69.0 % ECE). Our optimized membrane electrode assembly enhances the cell activity (1.567 V at 1.0 A cm−2; ECE = 76.5 %) and stability (0.125 mVcell h−1 at 0.5 A cm−2 for 500 h) with a 100 cm2 AEMWE stack.

In-situ detection of electrolyte defects in lithium-ion batteries using ultrasonic imaging and analysis of formation patterns

The urgent necessity for enhanced cycling performance in lithium batteries is paramount for electric vehicles to attain broader economic advantages. However, prolonged usage and cycling often lead to electrolyte de-wetting within the battery, posing a significant risk to battery safety and lifespan reduction. A thorough understanding of the mechanisms underlying electrolyte de-wetting is pivotal for the development of long-lasting batteries. This study employs an ultrasonic non-destructive testing method to investigate changes in the internal electrolyte during battery operation. Analysis of the results found that during to the relatively higher current density and temperature near the tabs, electrolyte de-wetting is more prone to occur in these areas, with defects being more severe at the positive electrode compared to the negative electrode. Finally, these issues are addressed to provide reasonable recommendations for future battery design and optimization.

Side-Reactions of Polyvinylidene Fluoride and Polyvinylidene Chloride Binders with Aluminum Chloride-Based Ionic Liquid Electrolyte in Rechargeable Aluminum-Batteries

Abstract Rechargeable aluminum batteries (RABs) use a Lewis acidic aluminum chloride (AlCl3) and 1-Ethyl-3-methylimidazolium chloride (EMImCl) ionic liquid electrolyte. Electrode fabrication often relies on procedures from lithium-ion batteries (LIBs), including the use of Polyvinylidene fluoride (PVdF) as a binder. However, PVdF reacts with Al2Cl7- in the RAB electrolyte, making it unsuitable for new battery types. The literature lacks details on the products formed, changes in the ionic liquid electrolyte, and the implications for electrochemical performance. With potential European Chemical Agency restrictions on per- and polyfluoroalkyl substances (PFAS) by 2025, Polyvinylidene chloride (PVdC) is being explored as an alternative binder. In contact with AlCl3:EMImCl (1.50:1.00) electrolyte, both, PVdF and PVdC transform into amorphous carbon during dehydrofluorination and dehydrochlorination, respectively, as confirmed by Raman spectroscopy. Furthermore, via 19F-NMR, it is shown that the reaction time between the soaked polymers and the ionic liquid has a significant influence on the newly formed aluminum chlorofluoride complexes. Electrochemical tests of graphite-based electrodes indicate increasing specific capacity of PVdF compared to PVdC with a continuous number of cycles. Amorphous carbon can prevent the disintegration of graphite and enhance conductivity. Furthermore, newly formed AlF4- can run a co-intercalation and lead to increasing specific capacity.

The nephroprotective potential of selected synthetic compound against gentamicin induced nephrotoxicity

BackgroundNephrotoxicity, the rapid impairment of kidney function caused by harmful drugs and chemicals, affects about 20% of cases and is projected to become a leading cause of death by reactive oxygen species (ROS). Gentamicin (GM), an aminoglycoside antibiotic is one of the well know drugs/chemicals to cause nephrotoxicity both in humans and animals.MethodsA study on the effects of a synthetic phenolic compound, called 5-a, on GM-induced nephrotoxicity in male Wistar albino rats was conducted. The rats were grouped into five groups: normal control (NC), GM control (GM), positive control (GM + Dexa), treatment I (GM + 5-a 5 mg/kg) and treatment II (GM + 5-a 10 mg/kg). Throughout the experiment, the rats’ weights were monitored, and at its conclusion, their serum and kidney tissues were analyzed for renal function indicators and inflammatory markers. The study also included histopathological evaluations, molecular docking studies, blood and urine analyses for electrolyte changes, and behavioural assessments for central nervous system impact.Results2-{5-[(2-hydroxyethyl)-sulfanyl]-1,3,4-oxadiazol-2-yl} phenol (5-a) significantly protected against renal damage by reducing inflammatory markers, improving antioxidant defences, and decreasing kidney injury, particularly at higher doses. The findings suggest that compound 5-a, due to its anti-inflammatory and antioxidant properties, could be a promising therapeutic option for reducing gentamicin-induced nephrotoxicity and potentially for other kidney disorders in the future.ConclusionThese findings highlight the therapeutic effects of compound 5-a in alleviating gentamicin-induced nephrotoxicity.

Acid–base and electrolyte changes in dogs after packed red blood cell transfusion

AbstractBackgroundPacked RBC (pRBC) transfusions are often necessary to enhance organ perfusion and tissue oxygenation in cases of severe anemia.ObjectivesWe aimed to describe changes in acid–base and biochemical parameters in dogs after transfusion of pRBC and potential effects on the outcome.MethodsThe prospective observational study included anemic dogs requiring pRBC transfusions. Venous blood gas and electrolytes were measured pre‐transfusion and repeated within 1 h post‐transfusion. Signalment, pre‐existing conditions and underlying disease(s), number of days spent of hospitalization, the quantity of transfused pRBC units, and the outcome were also recorded. Associations between analytical values and all other parameters before and after transfusion were assessed using the Wilcoxon test. A generalized linear model was generated for each of the blood gas parameters post‐transfusion, including the pre‐transfusion values and the characteristics of the animal as fixed effects. The effect of the blood gas parameters on the mortality and hospitalization length was assessed using logistic regression and generalized linear models, respectively.ResultsTwenty‐six dogs with different causes of anemia were included in the study, with dogs remaining hospitalized for a median of 3 days (range: 0–11). Pre‐transfusion heart rate, respiratory rate, Angap, base excess, and lactate were higher than post‐transfusion values. Post‐transfusion results showed an increase in hematocrit, hemoglobin, HCO3‐, PCO2, tCO2, and chloride. Pre‐transfusion hypophosphatemia and receiving an increased volume of transfused pRBC were associated with a longer hospital stay, while higher pre‐transfusion lactate values were associated with higher mortality.ConclusionspRBC transfusion in anemic dogs was associated with an improvement in perfusion and acid–base parameters. Pre‐transfusion lactate may be an indicator of mortality in dogs.

Serum Electrolytes and Calcium Levels in Neonates Receiving Phototherapy for Neonatal Jaundice

Background: Neonatal Jaundice (NJ) is one of the most common causes of neonatal admission. Phototherapy is an important treatment modality for NJ. However, this treatment modality may itself result in changes of different biochemical parameters. The study aimed to evaluate the changes in serum electrolytes (Sodium, potassium and chloride) and calcium in neonates receiving phototherapy for NJ. Materials and methods: One hundred and two term neonates admitted to the Special Care Newborn Unit, Chattogram Medical College Hospital for the management of NJ by phototherapy were enrolled in this prospective observational study. Serum bilirubin, sodium, potassium, chloride and calcium were measured before and after 48 hours of phototherapy and compared. Results: The mean gestational age and mean age of admission of the neonates were 38.6±0.6 weeks and 6.42 ± .67 day respectively. The mean sodium, potassium and calcium level before therapy was respectively, 138.4±1.8 mmol/L, 4.1±0.3 mmol/L and 8.8±0.3 mg/dl. There was significant decrease in the level of mean sodium (136.4±1.6 mmol/L), potassium (3.8 ± 0.3 mmol/L) and calcium (8.4±0.4 mg/dL) after phototherapy. All neonates had normal level of serum calcium, sodium, potassium and chloride before phototherapy. After 48 hours of phototherapy, 46 (45.1%) of them had abnormal values with the incidence hypocalcaemia, hyponatraemia and hypokalemia respectively in 21.6%, 25.5% and 10.8% of the neonates. Conclusion: Neonates undergoing phototherapy are at risk of developing hyponatraemia, hypokalaemia and hypocalcaemia. Closed monitoring is essential to observe the changes in sodium, potassium and calcium and should be managed accordingly. IAHS Medical Journal Volume 6(2) December 2023; 83-86

Effect of Cycling on the Physical Properties of the Garnet Solid Electrolyte, LLZO

Solid-state energy storage is the future of high performance, high-energy-dense battery systems. A common solid electrolyte, argued to be viable for such a system is the ceramic garnet solid oxide solid electrolyte, LLZO. LLZO is preferred due to its high ionic conductivity and stability against lithium metal. To date, most mechano-electrochemical studies of this solid electrolyte only focus on the fabrication and cell performance of the solid electrolyte. For the first time, this work explores the effect cycling has on the physical properties of the LLZO solid electrolyte, where, after cycling, surface characterization is completed to understand the degradation effects of cycling, as well as the grain boundary-grain modifications that occur. Initial results indicate lithium nucleation in the grain boundaries occurs, where elemental mapping will allow for quantification of lithium concentration changes in the grain boundaries, indicating whether lithium exists in the grain as a pure metal or as an alloying compound. Indentation techniques are used to show that molecular stoichiometric changes of the solid electrolyte at the grain boundaries create a softer material, which would be more susceptible to dendrite protrusions, allowing for premature cell failure. This work provides valuable insight into the chemo-mechanical response of LLZO to lithium-ion migration across grain-grain boundary interfaces, helping guide materials engineering decisions for a more robust, electrochemically stable solid electrolyte. Figure 1

Direct Evidence of Reversible Changes in Electrolyte and its Interplay with LiO2 Intermediate in Li‐O2 Batteries (Small 31/2024)

Direct Evidence of Reversible Changes in Electrolyte and its Interplay with LiO₂ Intermediate in Li‐O₂ Batteries (Small 31/2024)

Stabilization of Li[NixMnyCo1-x-y]O2 structure using a mixture of Super-P and vapor-grown carbon fiber as conducting additives

Li[NixMnyCo1-x-y]O2 (NCM) has attracted considerable attention as a cathode material because of its excellent electrochemical performance; however, practical application of NCM is challenging owing to side reactions in the electrolyte and structural changes. In this study, we manufactured NCM electrodes with mixtures of Super-P and vapor-grown carbon fiber (VGCF) as conductive additives at different ratios (Super-P/VGCF=2/8 (S2V8), 5/5 (S5V5), and 8/2 (S8V2)) and investigated the effect of the ratio of the conductive additives on NCM electrode performance. Simply changing the ratio of the conductive additives without modifying the NCM active materials substantially altered the electrochemical performance. Using a Super-P/VGCF mixture at an appropriate ratio (5/5, w/w) forms a conductive network throughout the NCM active materials, improving the electrical conductivity and enabling uniform activation across the range of NCM particles. Consequently, for S5V5, the anisotropic volume changes of the NCM primary particles became uniform, resulting in structural stability of the secondary NCM particles during charging and discharging.

Instrumentation of novel optical sensor technology to detect the real-time electrolyte colour change in Li-on pouch cells

The need for new and improved diagnostic tools becomes paramount for Li-ion batteries in order to ensure their optimum performance along with their longevity and safety and there remain aspirational targets for Li-ion batteries regarding fast-charging, energy density, safety and lifetime that must be met to achieve further growth. The study of degradation mechanisms (such as electrolyte degradation, thermal runaway, gassing and cycling aging) at the cell level contributes significantly to the understanding of the aging phenomena and will enable improvements for future generations of LIBs. Among various indicators, the colour change of the electrolyte within Li-ion cells presents a largely unexplored avenue for assessing state of health and predicting early signs of degradation. This research proposes a new methodology for the development of an innovative optical sensor technology and its incorporation into a pouch cell. The sensor comprises of a photodiode and RGB LED, mounted on a single flexible PCB, capable of the real-time detection of electrolyte colour changes inside Li-ion pouch cells. Previous studies have identified electrolyte colour change as a potential marker for battery condition through various invasive testing methods; however, the proposed optical technique represents a step change in in-situ real-time diagnostics. This study elaborates on the process of developing and incorporating the sensors precisely into pouch cells and seeks to demonstrate the capability of these sensors to accurately detect alterations in the colour of the electrolyte as the cell ages, without having adverse effects on the cell's performance and offers the potential for direct correlation of electrolyte change with battery state of health.

Emergencies in nephrology

Emergencies in nephrology are mainly acute life-threatening situations for patients. Furthermore, one needs to consider constellations that are so damaging to the kidneys that the need for permanent dialysis develops within ashort period of time. Acute kidney failure as an immediate consequence is categorized using the Acute Kidney Injury Network (AKIN) stages and is pathophysiologically subdivided into pre-, intra- and post-renal. This leads to changes in volume status, acid base and electrolytes, while the terms nephrotic and nephritic describe the amount of kidney damage and help to choose diagnostic steps wisely. Patients that are already undergoing dialysis treatment or have received akidney transplant are afurther specific group in the case of emergencies.

Effects of propylene glycol in different doses on metabolic parameters in dairy cows

In the study, the effects of propylene glycol (PG) drenched in different doses in dairy cows with positive energy balance were evaluated on serum metabolic parameters. Twenty-four Simmental dairy cows in 60-190 days of lactation period with positive energy balance were included to this study. PG was drenched 3 h after morning feeding, at a doses of 300 mL (8 dairy cows) and 500 mL (8 dairy cows), once a day, for 3 days. Eight dairy cows were included for control group. Blood samples were collected once before PG drenching, daily after drenching of PG, and finally on day 4. Serum biochemical parameters were determined. With regard to energy metabolism, glucose concentrations from serum biochemical parameters significantly increased on day 3 in 500 mL PG group compared to control group, and there were not significant changes in BHBA and NEFA concentrations. Decreased urea, increased chloride concentrations were determined with within reference limits. In dairy cows with positive energy balance, 500 mL PG oral drenching had positive effect on energy balance as determined by serum glucose measurements, might not have negative effects on hepatic and renal function, and may cause serum electrolyte changes within reference limits.

The Correlation of Fluid Creep with Fluid and Electrolyte Imbalance In Pediatric Intensive Care Unit Dr. Cipto Mangunkusumo National Central Public Hospital.

Fluid creep, used as a drug diluent can contribute to fluid and electrolyte balance. Fluid creep brings substantial volume and electrolyte load to patients, especially in critically ill children. This study is conducted to evaluate the correlation of fluid creep with fluid and electrolyte balance in critically ill children. This cross-sectional study was conducted in a single tertiary center. We include children aged 1 month- 18 years in the pediatric intensive care unit (PICU). Exclusion criteria were patients receiving renal replacement therapy and plasmapheresis. Fluids and electrolyte intake were recorded at admission and the first 24 hours in the PICU. A total of 64 patients were observed. The sources of fluid intake are 61% from parenteral, 25% from enteral nutrition, and 12% from fluid creep. There were significant correlations between the volume (r = 0.304, P = .015) and electrolyte intake (r = 0.742, P = .035) of fluid creep with daily fluid balance. There is no correlation between fluid creep and electrolyte changes in 24 hours. Fifty-two patients used WFI (81.2%) as a drug diluent. Our study showed that fluid creep constitutes 12% of daily fluid intake. There is a correlation between the volume and electrolyte intake from fluid creep to daily fluid balance, so it is important to include the volume of fluid creep in calculating the fluid balance. Thus, it is recommended to use hypotonic fluid like WFI compared to NaCl 0.9% for drug diluent.

Porcine lungs perfused with three different flows using the 8-h open-atrium cellular ex vivo lung perfusion technique.

The number of lung transplantations is limited due to the shortage of donor lungs fulfilling the standard criteria. The ex vivo lung perfusion (EVLP) technique provides the ability of re-evaluating and potentially improving and treating marginal donor lungs. Accordingly, the technique has emerged as an essential tool to increase the much-needed donor lung pool. One of the major EVLP protocols, the Lund protocol, characterized by high pulmonary artery flow (100% of cardiac output [CO]), an open atrium, and a cellular perfusate, has demonstrated encouraging short-EVLP duration results. However, the potential of the longer EVLP duration of the protocol is yet to be investigated, a duration which is considered necessary to rescue more marginal donor lungs in future. This study aimed to achieve stable 8-h EVLP using an open-atrium cellular model with three different pulmonary artery flows in addition to determining the most optimal flow in terms of best lung performance, including lung electrolytes and least lung edema formation, perfusate and tissue inflammation, and histopathological changes, using the porcine model. EVLP was performed using a flow of either 40% (n = 6), 80% (n = 6), or 100% (n = 6) of CO. No flow rate demonstrated stable 8-h EVLP. Stable 2-h EVLP was observed in all three groups. Insignificant deterioration was observed in dynamic compliance, peak airway pressure, and oxygenation between the groups. Pulmonary vascular resistance increased significantly in the 40% group (p < .05). Electrolytes demonstrated an insignificant worsening trend with longer EVLP. Interleukin-8 (IL-8) in perfusate and tissue, wet-to-dry weight ratio, and histopathological changes after EVLP were insignificantly time dependent between the groups. This study demonstrated that stable 8-h EVLP was not feasible in an open-atrium cellular model regardless of the flow of 40%, 80%, or 100% of CO. No flow was superior in terms of lung performance, lung electrolytes changes, least lung edema formation, minimal IL-8 expression in perfusate and tissue, and histopathological changes.

Changes in Blood Electrolytes Induced by Anesthesia

Electrolyte imbalances can significantly impact anaesthesia management, potentially leading to complications during procedures. Hyponatremia, hyperkalemia, and metabolic acidosis can disrupt crucial physiological processes required for safe anaesthesia, affecting nerve transmission and heart function. Maintaining the proper fluid and electrolyte balance is essential for the body to function normally, emphasizing the importance of monitoring electrolytes during anaesthesia to prevent complications. To investigate the effects of anaesthesia on blood electrolytes, a prospective Cross-sectional design; An observational study was conducted in four hospitals from May to September 2023, involving 50 patients. The study utilized statistical analysis with SPSS, using the Wilcoxon signed-rank test to assess electrolyte levels before and after anaesthesia. A significance level of p&lt;0.05 was considered significant in the analysis. The study sample comprised 50 individuals, with 66% females and 34% males, the majority of them were within the 18-60 age range, with the highest proportion in the 20-29 category. Blood tests conducted pre- and post-anaesthesia showed varying distributions: 58% under general anaesthesia, 34% under spinal anaesthesia, and 8% under local anaesthesia. The Wilcoxon signed-rank test results indicated no statistically significant differences in electrolyte means immediately after anaesthesia, suggesting that anaesthesia did not directly impact electrolyte levels. Maintaining correct electrolyte balance is crucial during anaesthesia to ensure normal physiological function and prevent complications that could influence patient outcomes. By recognising the significance of electrolytes, addressing imbalances, and leveraging advancements in research and technology, patient safety and surgical outcomes can be enhanced.

The Potential Neurological Impact of Intraoperative Hyponatremia Using Histidine-Tryptophan-Ketoglutarate Cardioplegia Infusion in Adult Cardiac Surgery.

Background and Objectives: The relationship between histidine-tryptophan-ketoglutarate (HTK)-induced hyponatremia and brain injury in adult cardiac surgery patients is unclear. This study analyzed postoperative neurological outcomes after intraoperative HTK cardioplegia infusion. Materials and Methods: A prospective cohort study was conducted on 60 adult patients who underwent cardiac surgery with cardiopulmonary bypass. Of these patients, 13 and 47 received HTK infusion and conventional hyperkalemic cardioplegia, respectively. The patients' baseline characteristics, intraoperative data, brain injury markers, Mini-Mental State Examination (MMSE) scores, and quantitative electroencephalography (qEEG) data were collected. Electrolyte changes during cardiopulmonary bypass, the degree of hyponatremia, and any associated brain insults were evaluated. Results: The HTK group presented with acute hyponatremia during cardiopulmonary bypass, which was intraoperatively corrected through ultrafiltration and normal saline administration. Postoperative sodium levels were higher in the HTK group than in the conventional cardioplegia group. The change in neuron-specific enolase levels after cardiopulmonary bypass was significantly higher in the HTK group (p = 0.043). The changes showed no significant differences using case-control matching. qEEG analysis revealed a significant increase in relative delta power in the HTK group on postoperative day (POD) 7 (p = 0.018); however, no significant changes were noted on POD 60. The MMSE scores were not significantly different between the two groups on POD 7 and POD 60. Conclusions: HTK-induced acute hyponatremia and rapid correction with normal saline during adult cardiac surgeries were associated with a potential short-term but not long-term neurological impact. Further studies are required to determine the necessity of correction for HTK-induced hyponatremia.

Comparative Analysis on Aluminium Interdigitated Electrode Surface: Influence of Ionic Strength and Electrolytes Changes

The field of generating surface thin films in sensing applications is emerging, and the incorporation of thin film technology into sensor development for enhanced sensing is becoming increasingly significant in various industries such as healthcare, environmental monitoring, and food safety. However, in order to achieve higher specificity in biosensing, advances in nanomaterial biofunctionalization are crucial. This research focuses on the fabrication and characterization of nanobiosensors with surface modification using two different sensing materials: zinc oxide and gold nanorod nanocomposites. The aim of this study was to enhance the sensing capabilities of nanobiosensors by incorporating surface modification with different sensing materials. The fabrication of nanobiosensors involved using silicon as the base material and conventional photolithography to fabricate aluminium interdigitated electrodes with three different structures and gap sizes. AutoCAD software was utilized to create three different photo masks with varying gap sizes. Physical characterization of the fabricated ALIDEs was conducted using atomic force microscope, high power microscope, scanning electron microscope, and 3D-profilormeter. The electrical characterization of the ALIDEs was performed using a Keithley 6487 picoammeter. I-V measurements were conducted on bare ALIDEs as well as surface modified ALIDEs with zinc oxide and gold nanorod. I-V measurements were also performed for pH scouting. The I-V measurements on bare ALIDEs revealed that ALIDEs modified with gold nanorod conducted the least current compared to ALIDEs modified with zinc oxide. Furthermore, the ALIDEs modified with gold nanorod were found to be stable under various electrolytes environments after undergoing pH scouting.

#570 A study of QTc time trends and factors affecting QTc changes during dialysis

Abstract Background and Aims Several studies have revealed the relationship between an abnormal QTc interval and mortality with sudden death in patients undergoing haemodialysis (HD). The QTc interval in HD is regulated by several factors, such as electrolytes, pH, and drugs. However, few studies have investigated the changes in the QTc interval during HD sessions and the determining factors. Therefore, we investigated the relationship between changes in electrolytes and QTc interval during HD. Method In this cross-sectional study, 53 patients undergoing maintenance HD were enrolled. Electrocardiogram and blood samples were obtained two days after dialysis. QTc was measured every hour from the start of the HD session, and blood samples were collected at the start, 2 h after, and at the end of the HD session. At the start of the HD session, we measured the blood levels of urea nitrogen, creatinine, β2-microglobulin (β2MG), HCO3-, albumin, intact-parathyroid hormone, phosphorus, Ca, Mg, and K. Blood Ca, Mg, K, and HCO3- levels were evaluated at the start, 2 h after, and at the end of the HD session. The relationship between changes in the QTc interval and various parameters was analysed by Spearman correlation analysis and multiple regression analysis. Results The patients were aged 37–91 (median; 71.5) years, and the duration of dialysis was 1–402 months (median; 2 months). Of the patients, 40.4% were diagnosed as the prolonged QTc interval (≥460 ms) at the start of HD (median; 455 ms). Conversely, 15.9% of patients at 2 h after the start of HD (median; 444 ms) and 8.4% of patients at end of HD (447 ms) were normalized in QTc interval. The peak change in the QTc interval occurred 2 h after start of HD. Thus, we estimated the factors that affected the change in QTc 2 h after the start of dialysis (ΔQTc2h). The duration of HD treatment (r = 0.312, P = 0.025) and serum levels of β2MG (r = 0.324, P = 0.019) were positively correlated with ΔQTc2h. The 2-h change in corrected Ca (ΔcCa2h) (r = −0. 31, P = 0.03) and intact-PTH (r = −0.30, P = 0.035) were negatively correlated with ΔQTc2h. We found no significant correlation between ΔQTc2h and changes in K and Mg. According to the multiple regression analysis, ΔcCa2h (β = −0.293, P = 0.033) and β2MG (β = 0.271, P = 0.042) were significant predictors of ΔQTc2h. Conclusion We anticipated that QTc interval might be prolonged due to the decreased serum K and Mg levels via HD treatments. However, QTc levels during HD were shortened according to increased serum Ca levels. Among the electrolyte levels, the change in blood Ca was significantly correlated with the change in the QTc interval but not with the change in Mg and K. The study results suggest the importance of optimal dialysate electrolytes composition to prevent adverse events and premature death caused by abnormalities in the QTc interval.

#3060 Assessment of differences in management and outcomes of severe hypophosphatemia secondary to refeeding syndrome

Abstract Background and Aims Refeeding syndrome is a severe, potentially life-threatening condition characterized by fatal shifts in fluids and electrolytes that may occur in malnourished patients receiving parenteral or enteral artificial refeeding. This condition may present with hypokalemia, hypomagnesemia, thiamine deficiency and changes in glucose and fat metabolism, but the hallmark of the syndrome is hypophosphatemia. The rise in insulin during refeeding may lead to a significant uptake and utilization of phosphorus into the cells, leading to a deficit in intracellular and extracellular phosphorus. The best method for phosphate repletion has not yet been determined. In this study we describe the different management strategies and outcomes of severe hypophosphatemia secondary to refeeding syndrome observed at our centre. Method We performed a retrospective observational study of patients admitted at out tertiary hospital from December 2022 and May 2023 who presented severe hypophosphatemia (defined as serum phosphate level &amp;lt;1.2 mg/dl) secondary to refeeding syndrome. We collected demographic data, comorbidities, changes in electrolytes and kidney function and treatments received during in-hospital admission. Our outcomes were development of complications associated with severe hypophosphatemia (convulsions, myopathy, fractures, haemolytic anemia, and major cardiovascular events) and death. Results We identified 16 cases of severe hypophosphatemia secondary to refeeding syndrome during the study period, with a mean phosphate level of 0.81 ± 0.26 mg/dl. Mean age was 54.7 ± 16.4 years, and females were predominant (62.5%), and all were associated with parenteral nutrition. 18.8% of patients had had previous episodes of severe hypophosphatemia, 25% presented diarrhoea as well and 18.8% had also received intravenous iron previous to the episode. At presentation, mean serum creatinine was 0.64 ± 0.3 mg/dl, mean potassium levels were 3.5 ± 0.9 mmol/l, mean sodium 141.7 ± 6.3 mmol/l, mean calcium was 8.62 ± 0.37 mg/dl and mean magnesium was 2.05 ± 0.45 mg/dl. Most patients (75%) were treated by discontinuation of parenteral nutrition and intravenous phosphate, while 18.8% of patients were only treated by temporary discontinuation of parenteral nutrition and only 1 patient (6.3%) was treated with oral phosphate supplementation. Regarding complications, 18.8% of patients presented myopathy, 12.5% presented convulsions, 25% presented major cardiovascular events, and 18.8% of patients died during hospitalization. Conclusion Refeeding syndrome is a potential fatal condition that frequently presents with severe hypophosphatemia, however it frequently passes unrecognized. Prompt detection and management is essential, especially in patients receiving parenteral nutrition, to prevent complications and death. Further research is needed to determine the best management strategy in refeeding syndrome to improve outcomes.