Hyponatremia in the emergency department.

Hyponatremia, defined as a serum sodium <135 mmol/L, is frequently encountered in patients presenting to the emergency department. Symptoms are often unspecific and include a recent history of falls, weakness and vertigo. Common causes of hyponatremia include diuretics, heart failure as well as Syndrome of Inappropriate Antidiuresis (SIAD) and correct diagnosis can be challenging. Emergency treatment of hyponatremia should be guided by presence of symptoms and focus on distinguishing between acute and chronic hyponatremia.

Sodium and potassium disorders in patients with COPD exacerbation presenting to the emergency department.

BACKGROUND: Electrolyte disorders are common in the emergency department. Hyponatremia is known to be associated with adverse outcome in community-acquired pneumonia (CAP) and acute exacerbation of chronic obstructive pulmonary disease (AECOPD). No studies investigating the prevalence and influence of hypernatremia or potassium disorders in patients with AECOPD exist. METHODS: In this retrospective cohort analysis, the prevalence of sodium and potassium disorders was investigated in patients with AECOPD presenting to an emergency department (ED) between January 1st 2017 and December 31st 2018 and compared to all ED patients with electrolyte measurements and patients presenting with CAP. Exclusion criteria were age younger than 18 years, written or verbal withdrawal of consent and outpatient treatment. Additionally, the influence of dysnatremias and dyskalemias on outcome measured by ICU admission, need for mechanical ventilation, length of hospital stay, 30-day re-admission, 180-day AECOPD recurrence and in-hospital mortality and their role as predictors of disease severity measured by Pneumonia Severity Index (PSI) were investigated in patients with AECOPD. RESULTS: Nineteen point nine hundred forty-eight ED consultations with measurements of sodium and potassium were recognized between January 1st 2017 and December 31st 2018 of which 102 patients had AECOPD. Of these 23% had hyponatremia, 5% hypernatremia, 16% hypokalemia and 4% hyperkalemia on admission to the ED. Hypo- and hypernatremia were significantly more common in patients with AECOPD than in the overall ED population: 23 versus 11% (p = 0.001) for hypo- and 5% versus 0.6% (p < 0.001) for hypernatremia. In the logistic regression analysis, no association between the presence of either sodium or potassium disorders and adverse outcome were found. CONCLUSION: Dysnatremias and dyskalemias are common in patients with AECOPD with as many as 1 in 5 having hyponatremia and/or hypokalemia. Hypo- and hypernatremia were significantly more common in AECOPD than overall. No significant association was found for dysnatremias, dyskalemias and adverse outcomes in AECOPD.

The syndrome of inappropriate antidiuresis after vaccination against COVID-19: case report.

BACKGROUND: The Syndrome of Inappropriate Antidiuresis (SIADH) has been described to be associated with a multitude of conditions and medications, including the severe acute respiratory syndrome coronavirus 2. We describe the case of a patient with newly diagnosed and symptomatic SIADH after receiving the second COVID-19 vaccination not explained otherwise. CASE PRESENTATION: A 79-year-old male person was admitted to the emergency department due to a worsening of his general health state expressed by weakness, fatigue and anorexia. Vital signs and clinical findings were normal, in particular the patient was considered to be euvolemic. Laboratory investigations revealed a serum sodium of 117 mmol/L, a serum osmolality of 241 mosm/kg and a urea of 1.2 mmol/L with creatinine within normal range. Urine chemistry showed a urine osmolality of 412 mosm/kg and urine sodium of 110 mmol/L. TSH, C-reactive protein, and basal cortisol levels were normal. Under therapy with balanced crystalloid fluids, hyponatremia worsened and in absence of diuretic medications, diagnosis of SIADH was made. Since fluid restriction was not sufficiently effective, oral urea was administered. Under this therapy regimen hyponatremia resolved. CONCLUSIONS: Local as well as systemic reactions have been described for the new mRNA-based vaccines including pain and fever. Therefore, it is imaginable that the vaccine might trigger SIADH in some patients.

Characteristics of very elderly patients in the emergency department - A retrospective analysis.

INTRODUCTION: Elderly people, defined by age 65 years and older, made up 18.45% of the Swiss Population in 2018 and their number is projected to rise continuously. Data investigating specific characteristics of this patient subgroup, especially in the emergency setting, is scarce. METHODS: Demographic data of admission records from all patients aged 65 years or older admitted to our emergency department (ED) between January 1st 2015 and December 31st 2018 were investigated. Retrospective chart reviews of patients admitted in 2018 were conducted. Comorbidity burden was assessed by Charlson Comorbidity Index. Risk factors for death, longer hospitalization and placement in a nursing facility were identified by multivariate regression. RESULTS: The prevalence of elderly patients (≥65 years) admitted to the ED between 2015 and 2018 was rising from 33% in 2015 to 37.8% in 2018. In 2018 709 patients were 90 years and older (3.6%). Age above 90 years and high comorbidity burden were identified as independent risk factors for death. Polypharmacy, hyponatremia and high comorbidity burden were independent risk factors for longer hospitalizations. Advanced age and high comorbidity burden were independent risk factors for placement in a nursing facility. CONCLUSION: The number of elderly patients admitted to our ED is continuously rising. There was no difference in overall disease burden, number of medications and hospital length of stay between octogenarians and nonagenarians. We identified risk factors for mortality, long hospitalizations and need of placement in a nursing facility.

Gender distribution in board memberships of emergency medicine societies.

BACKGROUND: Gender gaps have been described regarding the chairpersons in academic emergency departments, the composition of editorial boards and publications in emergency medicine. The objective of this study was to determine the gender distribution of chairpersons and board members of emergency medicine societies worldwide. MATERIALS AND METHODS: In this cross-sectional analysis, websites of national emergency medicine societies worldwide were screened for the composition of executive boards and the respective chairpersons. The gender of the board members and chairpersons was obtained either by the profile on the respective web site and/or by internet search and gender identification software. Descriptive statistics were performed and results for national societies were stratified by continent. RESULTS: A total of 61 boards of national emergency medicine societies were analyzed. Detailed information on the board composition was available for 50 societies, of which 27 were from Europe, 10 from Asia, five from Africa, four from North America, three from South America and one from Australasia. A total of 603 persons were included in the analysis. 45 (82%) of the listed societies' presidents were male, while 10 (18%) were female. 385 (70%) of the non-president board members were male. The highest proportion of female board members was seen in Australia/New Zealand with five out of eight persons (62%) followed by South America with 13 out of 29 (45%). CONCLUSIONS: A marked gender disparity was found for emergency medicine societies worldwide in terms of chair functions as well as board composition. Wide regional differences were found between world regions.

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

BACKGROUND: No data concerning the prevalence and risk factors of dyskalemia in acute kidney injury (AKI) exist. We investigated (a) prevalence rates, (b) risk factors and (c) outcome of hypo- and hyperkalemia in emergency patients. METHODS: In this cross-sectional analysis, all patients admitted to the emergency department of a large public hospital in Switzerland between January 1st 2017 and December 31st 2018 with measurements of creatinine and potassium were included. Baseline characteristics, medication and laboratory data were extracted. Chart reviews were performed to identify patients with a diagnosis of chronic kidney disease (CKD) and to extract their baseline creatinine. For all other patients, the ADQI backformula was used in order to calculate baseline creatinine. AKI was graduated using creatinine criteria of the acute kidney injury network. Binary logistic regression analysis was used to identify risk factors for appearance of hyperkalemia and outcome. RESULTS: AKI was found in 8% of patients. Hyperkalemia was present in 13% and hypokalemia in 11% of patients with AKI. AKI stage, potassium-sparing diuretics, ACE inhibitors and underlying CKD were the strongest risk factors for hyperkalemia. Hyperkalemia as well as profound hypokalemia were independently associated with prolonged length of stay and in-hospital mortality. The study is limited by its dependency on chart review data in order to identify patients with chronic kidney disease and by limitations of the ADQI backformula to calculate baseline creatinine. CONCLUSIONS: Dyskalemias are common in emergency patients with AKI and are independent risk factors for adverse outcomes. Potassium-sparing diuretics, ACE-inhibitors, AKIN stage and CKD are predictors of hyperkalemia in AKI.

Potassium homeostasis and management of dyskalemia in kidney diseases: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference.

Potassium disorders are common in patients with kidney disease, particularly in patients with tubular disorders and low glomerular filtration rate. A multidisciplinary group of researchers and clinicians met in October 2018 to identify evidence and address controversies in potassium management. The issues discussed encompassed our latest understanding of the regulation of tubular potassium excretion in health and disease; the relationship of potassium intake to cardiovascular and kidney outcomes, with increasing evidence showing beneficial associations with plant-based diet and data to suggest a paradigm shift from the idea of dietary restriction toward fostering patterns of eating that are associated with better outcomes; the paucity of data on the effect of dietary modification in restoring abnormal serum potassium to the normal range; a novel diagnostic algorithm for hypokalemia that takes into account the ascendency of the clinical context in determining cause, aligning the educational strategy with a practical approach to diagnosis; and therapeutic approaches in managing hyperkalemia when chronic and in the emergency or hospital ward. In sum, we provide here our conference deliberations on potassium homeostasis in health and disease, guidance for evaluation and management of dyskalemias in the context of kidney diseases, and research priorities in each of the above areas.

Dysnatremias in emergency patients with acute kidney injury: A cross-sectional analysis.

PURPOSE: We aimed to investigate the prevalence, risk factors and outcome of hypo- and hypernatremia in emergency patients with acute kidney injury (AKI). METHODS: In this cross-sectional analysis all emergency patients between January 1st 2017 and December 31st 2018 with measurements of creatinine and sodium were included. Baseline characteristics, medication and laboratory data were gathered. Chart reviews were performed to identify patients with a diagnosis of chronic kidney disease (CKD) and to extract baseline creatinine. For all other patients the ADQI backformula was used to calculate baseline creatinine. AKI was graduated using creatinine criteria of the acute kidney injury network. Binary logistic regression analysis was used to identify risk factors for appearance of dysnatremias and outcome. RESULTS: AKI was found in 8% of patients. 392 patients (23.16%) had hyponatremia, 24 (1.4%) had hypernatremia. Use of potassium sparing diuretics, a medical cause for emergency referral, use of thiazide diuretics and AKI stage were the strongest risk factors for hyponatremia. Loop diuretics, a medical cause for emergency referral and AKI stage were risk factors for hypernatremia. In patients with all classes of hyponatremia, length of hospital stay was significantly longer compared to patients with a normal serum sodium. In the binary logistic regression analysis with death as outcome, hyponatremia as well as severe hypernatremia were independent risk factors for mortality. CONCLUSIONS: Dysnatremias are common in emergency patients with AKI. Diuretic medication is a major risk factor for hypo- and hypernatremia. Both hyponatremia and severe hypernatremia were independent risk factors for adverse outcome.

Acid-base disorders in liver disease.

Alongside the kidneys and lungs, the liver has been recognised as an important regulator of acid-base homeostasis. While respiratory alkalosis is the most common acid-base disorder in chronic liver disease, various complex metabolic acid-base disorders may occur with liver dysfunction. While the standard variables of acid-base equilibrium, such as pH and overall base excess, often fail to unmask the underlying cause of acid-base disorders, the physical-chemical acid-base model provides a more in-depth pathophysiological assessment for clinical judgement of acid-base disorders, in patients with liver diseases. Patients with stable chronic liver disease have several offsetting acidifying and alkalinising metabolic acid-base disorders. Hypoalbuminaemic alkalosis is counteracted by hyperchloraemic and dilutional acidosis, resulting in a normal overall base excess. When patients with liver cirrhosis become critically ill (e.g., because of sepsis or bleeding), this fragile equilibrium often tilts towards metabolic acidosis, which is attributed to lactic acidosis and acidosis due to a rise in unmeasured anions. Interestingly, even though patients with acute liver failure show significantly elevated lactate levels, often, no overt acid-base disorder can be found because of the offsetting hypoalbuminaemic alkalosis. In conclusion, patients with liver diseases may have multiple co-existing metabolic acid-base abnormalities. Thus, knowledge of the pathophysiological and diagnostic concepts of acid-base disturbances in patients with liver disease is critical for therapeutic decision making.

Use of Diuretics is not associated with mortality in patients admitted to the emergency department: results from a cross-sectional study.

BACKGROUND: Patients with diuretic therapy are at risk for drug-induced adverse reactions. It is unknown if presence of diuretic therapy at hospital emergency room admission is associated with mortality. METHODS: In this cross sectional analysis, all emergency room patients 2010 and 2011 at the Inselspital Bern, Switzerland were included. A multivariable logistic regression model was performed to assess the association between pre-existing diuretic medication and 28 day mortality. RESULTS: Twenty-two thousand two hundred thirty-nine subjects were included in the analysis. A total of 8.5%, 2.5%, and 0.4% of patients used one, two, or three or more diuretics. In univariate analysis spironolactone, torasemide and chlortalidone use were associated with 28 day mortality (all p < 0.05). In a multivariate cox regression model no association with mortality was detectable (p > 0.05). No difference existed between patients with or without diuretic therapy (P > 0.05). Age and creatinine were independent risk factors for mortaliy (both p < 0.05). CONCLUSION: Use of diuretics is not associated with mortality in an unselected cohort of patients presenting in an emergency room.

Use of Calcium Channel Blockers is Associated with Mortality in Patients with Chronic Kidney Disease.

BACKGROUND/AIMS: The use of antihypertensive medicines has been shown to reduce proteinuria, morbidity, and mortality in patients with chronic kidney disease (CKD). A specific recommendation for a class of antihypertensive drugs is not available in this population, despite the pharmacodynamic differences. We have therefore analysed the association between antihypertensive medicines and survival of patients with chronic kidney disease. METHODS: Out of 2687 consecutive patients undergoing kidney biopsy a cohort of 606 subjects with retrievable medical therapy was included into the analysis. Kidney function was assessed by glomerular filtration rate (GFR) estimation at the time point of kidney biopsy. Main outcome variable was death. RESULTS: Overall 114 (18.7%) patients died. In univariate regression analysis the use of alpha-blockers and calcium channel antagonists, progression of disease, diabetes mellitus (DM) type 1 and 2, arterial hypertension, coronary heart disease, peripheral vascular disease, male sex and age were associated with mortality (all p<0.05). In a multivariate Cox regression model the use of calcium channel blockers (HR 1.89), age (HR 1.04), DM type 1 (HR 8.43) and DM type 2 (HR 2.17) and chronic obstructive pulmonary disease (HR 1.66) were associated with mortality (all p < 0.05). CONCLUSION: The use of calcium channel blockers but not of other antihypertensive medicines is associated with mortality in primarily GN patients with CKD.

An acetate-buffered balanced crystalloid versus 0.9% saline in patients with end-stage renal disease undergoing cadaveric renal transplantation: a prospective randomized controlled trial.

BACKGROUND: Recent studies have shown a decline in glomerular filtration rate and increased renal vasoconstriction after administration of normal saline when compared with IV solutions with less chloride. In this study, we investigated the impact of normal saline versus a chloride-reduced, acetate-buffered crystalloid on the incidence of hyperkalemia during cadaveric renal transplantation. The incidence of metabolic acidosis and kidney function were secondary aims. METHODS: In this prospective randomized controlled trial, 150 patients received normal saline or an acetate-buffered balanced crystalloid during and after cadaveric renal transplantation. Venous blood gases were obtained at the start of anesthesia and every 30 minutes until discharge from the postoperative surveillance unit. Serum creatinine and 24-hour urine output were obtained on postoperative days 1, 3, and 7. RESULTS: Patients received a similar amount of fluid (median: 2625mL [interquartile range: 2000 to 3100] vs 2500 mL [2000 to 3050], P = 0.83). Hyperkalemia, defined as serum potassium >5.9 mmol/L, occurred in 13 patients (17%) in the saline and 15 (21%) in the balanced group (P = 0.56; difference between proportions -0.037 [-16.5% to 8.9%]). Minimum base excess was lower in the saline group compared with the balanced regimen (-4.5 mmol/L [-6 to -2.4] vs -2.6 mmol/L [-4 to -1], P < 0.001) and maximum chloride was significantly higher in the saline group (109 mmol/L [107 to 111] vs 107 mmol/L [105 to 109], P < 0.001). No difference in creatinine or urine output was seen postoperatively. Significantly more patients needed catecholamines in the saline group (30% vs 15%, P = 0.03). CONCLUSIONS: The incidence of hyperkalemia differed by less than 17% between groups. Use of balanced crystalloid resulted in less hyperchloremia and metabolic acidosis. Significantly more patients in the saline group required administration of catecholamines for circulatory support.

Clinical symptoms, signs and tests for identification of impending and current water-loss dehydration in older people.

BACKGROUND: There is evidence that water-loss dehydration is common in older people and associated with many causes of morbidity and mortality. However, it is unclear what clinical symptoms, signs and tests may be used to identify early dehydration in older people, so that support can be mobilised to improve hydration before health and well-being are compromised. OBJECTIVES: To determine the diagnostic accuracy of state (one time), minimally invasive clinical symptoms, signs and tests to be used as screening tests for detecting water-loss dehydration in older people by systematically reviewing studies that have measured a reference standard and at least one index test in people aged 65 years and over. Water-loss dehydration was defined primarily as including everyone with either impending or current water-loss dehydration (including all those with serum osmolality ≥ 295 mOsm/kg as being dehydrated). SEARCH METHODS: Structured search strategies were developed for MEDLINE (OvidSP), EMBASE (OvidSP), CINAHL, LILACS, DARE and HTA databases (The Cochrane Library), and the International Clinical Trials Registry Platform (ICTRP). Reference lists of included studies and identified relevant reviews were checked. Authors of included studies were contacted for details of further studies. SELECTION CRITERIA: Titles and abstracts were scanned and all potentially relevant studies obtained in full text. Inclusion of full text studies was assessed independently in duplicate, and disagreements resolved by a third author. We wrote to authors of all studies that appeared to have collected data on at least one reference standard and at least one index test, and in at least 10 people aged ≥ 65 years, even where no comparative analysis has been published, requesting original dataset so we could create 2 x 2 tables. DATA COLLECTION AND ANALYSIS: Diagnostic accuracy of each test was assessed against the best available reference standard for water-loss dehydration (serum or plasma osmolality cut-off ≥ 295 mOsm/kg, serum osmolarity or weight change) within each study. For each index test study data were presented in forest plots of sensitivity and specificity. The primary target condition was water-loss dehydration (including either impending or current water-loss dehydration). Secondary target conditions were intended as current (> 300 mOsm/kg) and impending (295 to 300 mOsm/kg) water-loss dehydration, but restricted to current dehydration in the final review.We conducted bivariate random-effects meta-analyses (Stata/IC, StataCorp) for index tests where there were at least four studies and study datasets could be pooled to construct sensitivity and specificity summary estimates. We assigned the same approach for index tests with continuous outcome data for each of three pre-specified cut-off points investigated.Pre-set minimum sensitivity of a useful test was 60%, minimum specificity 75%. As pre-specifying three cut-offs for each continuous test may have led to missing a cut-off with useful sensitivity and specificity, we conducted post-hoc exploratory analyses to create receiver operating characteristic (ROC) curves where there appeared some possibility of a useful cut-off missed by the original three. These analyses enabled assessment of which tests may be worth assessing in further research. A further exploratory analysis assessed the value of combining the best two index tests where each had some individual predictive ability. MAIN RESULTS: There were few published studies of the diagnostic accuracy of state (one time), minimally invasive clinical symptoms, signs or tests to be used as screening tests for detecting water-loss dehydration in older people. Therefore, to complete this review we sought, analysed and included raw datasets that included a reference standard and an index test in people aged ≥ 65 years.We included three studies with published diagnostic accuracy data and a further 21 studies provided datasets that we analysed. We assessed 67 tests (at three cut-offs for each continuous outcome) for diagnostic accuracy of water-loss dehydration (primary target condition) and of current dehydration (secondary target condition).Only three tests showed any ability to diagnose water-loss dehydration (including both impending and current water-loss dehydration) as stand-alone tests: expressing fatigue (sensitivity 0.71 (95% CI 0.29 to 0.96), specificity 0.75 (95% CI 0.63 to 0.85), in one study with 71 participants, but two additional studies had lower sensitivity); missing drinks between meals (sensitivity 1.00 (95% CI 0.59 to 1.00), specificity 0.77 (95% CI 0.64 to 0.86), in one study with 71 participants) and BIA resistance at 50 kHz (sensitivities 1.00 (95% CI 0.48 to 1.00) and 0.71 (95% CI 0.44 to 0.90) and specificities of 1.00 (95% CI 0.69 to 1.00) and 0.80 (95% CI 0.28 to 0.99) in 15 and 22 people respectively for two studies, but with sensitivities of 0.54 (95% CI 0.25 to 0.81) and 0.69 (95% CI 0.56 to 0.79) and specificities of 0.50 (95% CI 0.16 to 0.84) and 0.19 (95% CI 0.17 to 0.21) in 21 and 1947 people respectively in two other studies). In post-hoc ROC plots drinks intake, urine osmolality and axillial moisture also showed limited diagnostic accuracy. No test was consistently useful in more than one study.Combining two tests so that an individual both missed some drinks between meals and expressed fatigue was sensitive at 0.71 (95% CI 0.29 to 0.96) and specific at 0.92 (95% CI 0.83 to 0.97).There was sufficient evidence to suggest that several stand-alone tests often used to assess dehydration in older people (including fluid intake, urine specific gravity, urine colour, urine volume, heart rate, dry mouth, feeling thirsty and BIA assessment of intracellular water or extracellular water) are not useful, and should not be relied on individually as ways of assessing presence or absence of dehydration in older people.No tests were found consistently useful in diagnosing current water-loss dehydration. AUTHORS' CONCLUSIONS: There is limited evidence of the diagnostic utility of any individual clinical symptom, sign or test or combination of tests to indicate water-loss dehydration in older people. Individual tests should not be used in this population to indicate dehydration; they miss a high proportion of people with dehydration, and wrongly label those who are adequately hydrated.Promising tests identified by this review need to be further assessed, as do new methods in development. Combining several tests may improve diagnostic accuracy.

Age-related variety in electrolyte levels and prevalence of dysnatremias and dyskalemias in patients presenting to the emergency department.

BACKGROUND: It was found that age and female gender are predisposing factors for hyponatremia in patients taking thiazides. OBJECTIVE: To investigate whether a relationship exists between age and gender and serum sodium and potassium as well as the prevalence rates in a large population of patients presenting to the emergency department of a university hospital. METHODS: In this retrospective analysis we gathered data on age, gender and current diuretic medication of all patients admitted to the emergency department of a large university hospital with measurement of serum sodium and potassium between January 1, 2009 and December 31, 2010. Prevalence rates of and risk factors for electrolyte disorders were calculated on the basis of these data. RESULTS: A total of 20,667 patients were included in the analysis. Serum sodium levels declined significantly with increasing age while serum potassium rose, independent of diuretic medication at presentation. The prevalence rates of hyponatremia and hyperkalemia increased from 2.3% for hyponatremia in patients aged 16-21 years to 16.9% in patients aged >80 years and from 0.8% for hyperkalemia to 10.4%. In the regression analysis, age >60 years was a predictor for the presence of hyponatremia and hyperkalemia as was current use of diuretic medication. Male gender was associated with a decreased prevalence of hyponatremia and hypokalemia, while it was a predictor of hyperkalemia. CONCLUSIONS: Sodium levels were lower with increasing age, independent of diuretic intake, while potassium levels were higher. We found dramatically increasing prevalences of hyponatremia and hyperkalemia with increasing age, while no such effect could be found for hypernatremia and hypokalemia.

Fall-related emergency department admission: fall environment and settings and related injury patterns in 6357 patients with special emphasis on the elderly.

PRINCIPALS: Throughout the world, falls are a major public health problem and a socioeconomic burden. Nevertheless there is little knowledge about how the injury types may be related to the aetiology and setting of the fall, especially in the elderly. We have therefore analysed all patients presenting with a fall to our Emergency Department (ED) over the past five years. METHODS: Our retrospective data analysis comprised adult patients admitted to our Emergency Department between January 1, 2006, and December 31, 2010, in relation to a fall. RESULTS: Of a total of 6357 patients 78% (n = 4957) patients were younger than 75 years. The main setting for falls was patients home (n = 2239, 35.3%). In contrast to the younger patients, the older population was predominantly female (56.3% versus 38.6%; P < 0.0001). Older patients were more likely to fall at home and suffer from medical conditions (all P < 0.0001). Injuries to the head (P < 0.0001) and to the lower extremity (P < 0.019) occurred predominantly in the older population. Age was the sole predictor for recurrent falls (OR 1.2, P < 0.0001). CONCLUSION: Falls at home are the main class of falls for all age groups, particularly in the elderly. Fall prevention strategies must therefore target activities of daily living. Even though falls related to sports mostly take place in the younger cohort, a significant percentage of elderly patients present with falls related to sporting activity. Falls due to medical conditions were most likely to result in mild traumatic brain injury.

Renal function-adapted D-dimer cutoffs in combination with a clinical prediction rule to exclude pulmonary embolism in patients presenting to the emergency department.

D-dimer levels significantly increase with declining renal function and hence, renal function-adjusted D-dimer cutoffs to rule out pulmonary embolism were suggested. Aim of this study was to "post hoc" validate previously defined renal function-adjusted D-dimer levels to safely rule out pulmonary embolism in patients presenting to the emergency department. In this retrospective, observational analysis, all patients with low to intermediate pre-test probability receiving D-dimer measurement and computed tomography angiography (CTA) to rule out pulmonary embolism between January 2017 and December 2020 were included. Previously defined renal function-adjusted D-dimer cutoffs (1306 µg/l for moderate and 1663 µg/l for severe renal function impairment) were applied to determine sensitivity, specificity, negative and positive predictive values. One thousand, three hundred sixty-nine patients were included of which 229 (17%) were diagnosed with pulmonary embolism. The estimated glomerular filtration rate (eGFR) was ≥ 60 ml/min in 1079 (79%), 30-59 ml/min in 266 (19%) and < 30 ml/min in 24 (2%) patients. Only three patients (1.1%) with an eGFR < 60 ml/min had a D-dimer level < 500 µg/l. There was a significant correlation between D-dimer and eGFR (R = - 0.159, p < 0.001). Calculated on the standard D-dimer cutoff value of 500 µg/l, sensitivity of D-dimer testing was 97% for patients with an eGFR ≥ 60 ml/min and 100% for those with 30-60 ml/min, while specificity decreased in patients with renal function impairment. A negative predictive value of 0.99 as a premise to safely rule out pulmonary embolism was achieved by applying a D-dimer cutoff of 1480 µg/l for eGFR 30-59 ml/min and 1351 µg/l for eGFR < 30 ml/min. The findings of this study underline that application of renal function-adapted D-dimer levels in combination with a clinical prediction rule appears feasible to rule out pulmonary embolism. Out of the current dataset, renal function-adjusted D-dimer cutoffs to rule out pulmonary embolism were slightly different compared to previously defined cutoffs. Further studies on a larger scale are needed to validate possible renal function-adjusted D-dimer cutoffs.

[Consensus recommendations on the diagnosis and treatment of hyponatremia from the Austrian Society for Nephrology 2024]. / Konsensusempfehlungen zur Diagnose und Therapie der Hyponatriämie der Österreichischen Gesellschaft für Nephrologie 2024.

Hyponatremia is a disorder of water homeostasis. Water balance is maintained by the collaboration of renal function and cerebral structures, which regulate thirst mechanisms and secretion of the antidiuretic hormone. Measurement of serum-osmolality, urine osmolality and urine-sodium concentration help to diagnose the different reasons for hyponatremia. Hyponatremia induces cerebral edema and might lead to severe neurological symptoms, which need acute therapy. Also, mild forms of hyponatremia should be treated causally, or at least symptomatically. An inadequate fast increase of the serum sodium level should be avoided, because it raises the risk of cerebral osmotic demyelination. Basic pathophysiological knowledge is necessary to identify the different reasons for hyponatremia which need different therapeutic procedures.