Hospital-Associated Hypernatremia Spectrum and Clinical Outcomes in an Unselected Cohort

Effects of hypernatremia on the microglia

Signs and symptoms of hypernatremia largely indicate central nervous system dysfunction. Acute hypernatremia can cause demyelinating lesions similar to that observed in osmotic demyelination syndrome (ODS). We have previously demonstrated that microglia accumulate in ODS lesions and minocycline protects against ODS by inhibiting microglial activation. However, the direct effect of rapid rise in the sodium concentrations on microglia is largely unknown. In addition, the effect of chronic hypernatremia on microglia also remains elusive. Here, we investigated the effects of acute (6 or 24 h) and chronic (the extracellular sodium concentration was increased gradually for at least 7 days) high sodium concentrations on microglia using the microglial cell line, BV-2. We found that both acute and chronic high sodium concentrations increase NOS2 expression and nitric oxide (NO) production. We also demonstrated that the expression of nuclear factor of activated T-cells-5 (NFAT5) is increased by high sodium concentrations. Furthermore, NFAT5 knockdown suppressed NOS2 expression and NO production. We also demonstrated that high sodium concentrations decreased intracellular Ca2+ concentration and an inhibitor of Na+/Ca2+ exchanger, NCX, suppressed a decrease in intracellular Ca2+ concentrations and NOS2 expression and NO production induced by high sodium concentrations. Furthermore, minocycline inhibited NOS2 expression and NO production induced by high sodium concentrations. These in vitro data suggest that microglial activity in response to high sodium concentrations is regulated by NFAT5 and Ca2+ efflux through NCX and is suppressed by minocycline.

Sodium fluctuation as a parameter in predicting mortality in general hospitalized patients

Background

Dysnatremia is the most common electrolyte disorder in hospitalized patients. Sodium fluctuation level may be a better parameter in dysnatremia management. We aimed to examine the association between sodium fluctuation level during hospitalization and mortality and to evaluate its value in predicting poor prognosis among general hospitalized patients.

Methods

Data were collected from patients admitted to Peking Union Medical College Hospital. The generalized estimated equation (GEE) was used to examine the relationship between sodium fluctuation level and mortality. Receiver-operating characteristic (ROC) curve analysis was performed to calculate the optimal cutoff value and the area under the ROC curve (AUC).

Results

Sodium fluctuation level showed a dose-dependent association with increased mortality in general hospitalized patients. After adjusting age, sex, length of hospital stay, and Charlson comorbidity index, the ORs of group G2 to G6 were 5.92 (95% CI 5.16-6.79), 26.45 (95% CI 22.68-30.86), 50.71 (95% CI 41.78-61.55), 104.38 (95% CI 81.57-133.58), and 157.64 (95% CI 112.83-220.24), respectively, p trend <0.001. Both normonatremia and dysnatremia patients on admission had the dose-dependent associations similar to general hospitalized patients. The AUC of sodium fluctuation level was 0.868 (95% CI 0.859-0.877) in general hospitalized patients, with an optimal cutoff point of 7.5 mmol/L, a sensitivity of 76.5% and a specificity of 84.2%.

Conclusion

We determined that sodium fluctuation level had a dose-dependent association with increased mortality in general hospitalized patients. Sodium fluctuation level could be used to develop a single parameter system in predicting mortality in general hospitalized patients with acceptable accuracy, sensitivity, and specificity.

Systemic and iatrogenic factors contribute to the development of severe hypernatraemia in vulnerable inpatients

OBJECTIVES

To determine all-cause in-hospital mortality associated with severe hypernatraemia and the causes, comorbidities, time to treatment, discharge destination and postdischarge mortality.

DESIGN

Retrospective observational cohort study.

PATIENTS

Severe hypernatraemia, (sodium concentration ≥ 155 mmol/L), at any time during a tertiary hospital admission in Melbourne, Australia, 1 January 2019 to 31 December 2019 (pre-COVID19).

MEASUREMENTS

Deaths, Charlson Comorbidity Index (CCI), hypernatraemia causes, time to treatment, discharge destination.

RESULTS

One hundred and one inpatients: 64 community-acquired, 37 hospital-acquired. In-hospital mortality was 38%, but cumulative mortality was 65% by 1 month after discharge, with only a minor further increase at 6 and 12 months. After adjusting for peak sodium concentration, the community acquired group had significantly reduced odds of in-hospital mortality (odds ratio 0.15, 95% confidence interval [0.04-0.54], p = .003). Iatrogenic factors were present in 57% (21/37) of the hospital-acquired group. Only 55% of all cases received active sodium directed treatment. Time to start treatment did not affect outcomes. High levels of comorbidity were present, median CCI (IQR) was 6 (5-8) in the community and 5 (4-7) in the hospital group. Dementia prevalence was higher in the community group, 66% (42/64) versus 19% (7/37) (p = .001). Infection was the most common precipitant with 52% (33/64) in the community and 32% (12/37) in the hospital group. Of the survivors, 32% who had been living independently required residential care after discharge.

CONCLUSIONS

Mortality was high and loss of independence in survivors common. To potentially improve outcomes, hypernatraemia-specific guidelines should be formulated and efforts made to reduce system and iatrogenic factors.

Outcomes of Hospital-Acquired Hypernatremia

BACKGROUND

Hospital-acquired hypernatremia is highly prevalent, overlooked, and associated with unfavorable consequences. There are limited studies examining the outcomes and discharge dispositions of various levels of hospital-acquired hypernatremia in patients with or without CKD.

METHODS

We conducted an observational retrospective cohort study, and we analyzed the data of 1,728,141 patients extracted from the Cerner Health Facts database (January 1, 2000, to June 30, 2018). In this report, we investigated the association between hospital-acquired hypernatremia (serum sodium [Na] levels >145 mEq/L) and in-hospital mortality or discharge dispositions with kidney function status at admission using adjusted multinomial regression models.

RESULTS

Of all hospitalized patients, 6% developed hypernatremia after hospital admission. The incidence of in-hospital mortality was 12% and 1% in patients with hypernatremia and normonatremia, respectively. The risk of all outcomes was significantly greater for serum Na >145 mEq/L compared with the reference interval (serum Na, 135-145 mEq/L). In patients with hypernatremia, odds ratios (95% confidence interval) for in-hospital mortality, discharge to hospice, and discharge to nursing facilities were 14.04 (13.71 to 14.38), 4.35 (4.14 to 4.57), and 3.88 (3.82 to 3.94), respectively ( P < 0.001, for all). Patients with eGFR (Chronic Kidney Disease Epidemiology Collaboration) 60-89 ml/min per 1.73 m 2 and normonatremia had the lowest odds ratio for in-hospital mortality (1.60 [1.52 to 1.70]).

CONCLUSIONS

Hospital-acquired hypernatremia is associated with in-hospital mortality and discharge to hospice or to nursing facilities in all stages of CKD.

Disorders of Sodium

Sodium imbalances are a common occurrence in the emergency department. Although recognition and diagnosis are relatively straightforward, discovering the cause and management should be approached systematically. The most important history items to ascertain is if the patient has symptoms and how long this imbalance has taken to develop. Treatment rapidity depends on severity of symptoms with the most rapid treatment occurring in only the severely symptomatic. Overcorrection has dire consequences and must be approached in a careful and systematic fashion in order to prevent these devastating consequences.

Hypernatremia: Epidemiology and Predictive Role in Emerging and Established Acute Kidney Injury

Hypernatremia (plasma sodium > 145 mmol/L) reflects impaired water balance, and affected patients can suffer from severe neurologic symptoms. Hyponatremia, on the other hand, is the most frequent electrolyte disorder in hospitals. It may be diagnosed in acute kidney injury (AKI), but hyponatremia prior to the diagnosis of AKI has also predictive or prognostic value in the short term. Aim of the article was to summarize data on both, epidemiology and outcomes of in-hospital acquired hypernatremia ("In-hospital acquired" refers to the diagnosis of either hypo- or hypernatremia in patients, who did not exhibit any of these electrolyte imbalances upon admission to the hospital). It also aimed to discuss its predictive role in patients with emerging or established AKI. Five databases were searched for references: PubMed, Medline, Google Scholar, Scopus, and Cochrane Library. Studies published between 2000 and 2023 were screened. The following keywords were used: "hypernatremia", "mortality", "pathophysiology", "acute kidney injury", "AKI", "risk prediction", "kidney replacement therapy", "KRT", "renal replacement therapy", "RRT", "hyponatremia", and "heart failure". A total of 16 studies were deemed eligible for inclusion. Among these, 13 studies had a retrospective design, two investigations were published as secondary analyses from prospective trial cohorts, and one study was prospective in nature. Out of the 16 studies, 11 focused on the epidemiology and outcomes of hypernatremia, while five investigations were related to AKI and/or AKI-associated endpoints. The prevalence of hypernatremia diagnosed during hospitalization varied from 1.9% to 6.8%, with one exception where it was 30.8%. All studies demonstrated associations between hypernatremia and mortality, even over extended periods after discharge. In AKI patients, hypernatremia shows potential for predicting in-hospital death. In conclusion, hypernatremic individuals are at higher risk of death during in-hospital therapy. Also, the electrolyte disorder potentially qualifies as a future biomarker for AKI onset and AKI-associated mortality.

Risk stratification and predictive value of serum sodium fluctuation for adverse prognosis in acute coronary syndrome patients

BACKGROUND

Serum sodium fluctuation (SF) as an indicator of the extent of changes in serum sodium is associated with increased mortality in hospitalized patients. However, there is no consensus on diagnostic criteria for SF, and its impact on the outcome of patients with acute coronary syndrome (ACS) remains uncertain. We defined SF and assessed its association with adverse prognosis in hospitalized ACS patients.

METHODS

Patients diagnosed with ACS were consecutively recruited. The serum SF rate (SFR) was defined as the ratio of the difference between the highest and lowest serum sodium levels during hospitalization to the initial serum sodium level on admission. The Cox proportional hazards model was performed to evaluate the association between SFR and mortality. The dose-response relationships of SFR with mortality was characterized by restricted cubic splines (RCS) model. The predictive performance of SF for mortality was assessed by the area under the receiver operating characteristic curves (AUCs).

RESULTS

The study retrospectively enrolled 1856 ACS patients, of which 36 (1.94%) patients dead within 1 year. Multivariate Cox analysis showed that SFR was independently associated with higher risk of 1-year mortality (HR = 1.17, 95% CI: 1.111-1.244, P < 0.001). RCS analysis showed the optimal threshold for SFR was 5%, and the 1-year cumulative mortality was higher in the abnormal SF group (SFR ≥ 5%) compared with the normal SF group (SFR < 5%, P < 0.01). The AUCs of SF for predicting mortality within 1 month, 6 months, and 1 year were 0.842 (95% CI: 0.781-0.904), 0.830 (95% CI:0.736-0.926), 0.703 (95% CI:0.595--0.811), respectively. Even in patients with normal baseline serum sodium, abnormal SF group demonstrated a significantly higher 1-year mortality compared to normal SF group (HR = 4.955, 95% CI: 1.919-12.795).

CONCLUSION

The SFR during hospitalization is an adequate predictor of adverse outcomes in ACS patients, independent of serum sodium level at admission. Additional research is warranted to ascertain whether interventions targeting SF confer measurable clinical benefits.

The Association between Dysnatraemia during Hospitalisation and Post-COVID-19 Mental Fatigue

COVID-19 may induce short- and long-term cognitive failures after recovery, but the underlying risk factors are still controversial. Here, we investigated whether (i) the odds of experiencing persistent cognitive failures differ based on the patients' disease course severity and sex at birth; and (ii) the patients' electrolytic profile in the acute stage represents a risk factor for persistent cognitive failures. We analysed data from 204 patients suffering from COVID-19 and hospitalised during the first pandemic wave. According to the 7-point WHO-OS scale, their disease course was classified as severe or mild. We investigated the presence of persistent cognitive failures collected after hospital discharge, while electrolyte profiles were collected during hospitalisation. The results showed that females who suffered from a mild course compared to a severe course of COVID-19 had a higher risk of presenting with persistent mental fatigue after recovery. Furthermore, in females who suffered from a mild course of COVID-19, persistent mental fatigue was related to electrolyte imbalance, in terms of both hypo- and hypernatremia, during hospitalisation in the acute phase. These findings have important implications for the clinical management of hospitalised COVID-19 patients. Attention should be paid to potential electrolyte imbalances, mainly in females suffering from mild COVID-19.

Salt and Water: A Review of Hypernatremia

Serum sodium disorders are generally a marker of water balance in the body. Thus, hypernatremia is most often caused by an overall deficit of total body water. Other unique circumstances may lead to excess salt, without an impact on the body's total water volume. Hypernatremia is commonly acquired in both the hospital and community. As hypernatremia is associated with increased morbidity and mortality, treatment should be initiated promptly. In this review, we will discuss the pathophysiology and management of the main types of hypernatremia, which can be categorized as either a loss of water or gain of sodium that can be mediated by renal or extrarenal mechanisms.

Nomogram Prediction Model of Hypernatremia on Mortality in Critically Ill Patients

Objective

To investigate the value of hypernatremia in the intensive care unit (ICU) for the risk prediction of mortality in severe patients.

Methods

Clinical data of critically ill patients admitted to the ICU of Beijing Friendship Hospital, were collected for retrospective analysis. Univariate and multivariate logistic regression analyses were employed to analyze the influencing factors. Nomograms predicting the mortality were constructed with R software and validated with repeated sampling.

Results

A total of 442 cases were eligible for this study. Hypernatremia within 48 hours of ICU admission, change in sodium concentration (CNa+) within 48 hours, septic shock, APACHE II score, hyperlactatemia within 48 hours, use of continuous renal replacement therapy (CRRT) within 48 hours, and the use of mechanical ventilation (MV) within 48 hours of ICU admission were all identified as independent risk factors for death within 28 days of ICU admission. These predictors were included in a nomogram of 28-day mortality in severe patients, which was constructed using R software.

Conclusion

The nomogram could predict the individualized risk of 28-day mortality based on the above factors. The model has better discrimination and accuracy and has high clinical application value.

Evaluation and management of hypernatremia in adults: clinical perspectives

Hypernatremia is an occasionally encountered electrolyte disorder, which may lead to fatal consequences under improper management. Hypernatremia is a disorder of the homeostatic status regarding body water and sodium contents. This imbalance is the basis for the diagnostic approach to hypernatremia. We summarize the eight diagnostic steps of the traditional approach and introduce new biomarkers: exclude pseudohypernatremia, confirm glucose-corrected sodium concentrations, determine the extracellular volume status, measure urine sodium levels, measure urine volume and osmolality, check ongoing urinary electrolyte free water clearance, determine arginine vasopressin/copeptin levels, and assess other electrolyte disorders. Moreover, we suggest six steps to manage hypernatremia by replacing water deficits, ongoing water losses, and insensible water losses: identify underlying causes, distinguish between acute and chronic hypernatremia, determine the amount and rate of water administration, select the type of replacement solution, adjust the treatment schedule, and consider additional therapy for diabetes insipidus. Physicians may apply some of these steps to all patients with hypernatremia, and can also adapt the regimens for specific causes or situations.

Outcome of Hospitalized Cancer Patients with Hypernatremia: A Retrospective Case-Control Study

Hypernatremia (>145 mmol/L) is a relatively rare event, and the data regarding its role in the outcome of inpatients on an oncology ward are weak. The aim of this study was to describe the prevalence, prognosis, and outcome of hospitalized cancer patients with hypernatremia. We performed a retrospective case-control study of data obtained from inpatients with a solid tumor at the St. Claraspital, Basel, Switzerland, who were admitted between 2017 and 2020. The primary endpoint was overall survival. Hypernatremia was found in 93 (3.16%) of 2945 inpatients bearing cancer or lymphoma. From 991 eligible normonatremic control patients, 93 were matched according to diagnosis, age, and sex. The median overall survival time (OS) of patients with hypernatremia was 1.5 months compared to 11.7 months of the normonatremic controls (HR 2.69, 95% CI 1.85-3.90, p < 0.0001). OS of patients with irreversible compared to reversible hypernatremia was significantly shorter (23 versus 88 days, HR 4.0, 95% CI 2.04-7.70, p < 0.0001). The length of hospital stay was significantly longer for the hypernatremic than for the normonatremic group (p < 0.0001). Significantly more patients with hypernatremia died in the hospital (30.1% versus 8.6%, p < 0.001). These results suggest hypernatremia to be associated with an unfavorable outcome and a very short OS.

Hypernatremia in Hospitalized Patients: A Large Population-Based Study

Background

Hypernatremia is a frequently encountered electrolyte disorder in hospitalized patients. Controversies still exist over the relationship between hypernatremia and its outcomes in hospitalized patients. This study examines the relationship of hypernatremia to outcomes among hospitalized patients and the extent to which this relationship varies by kidney function and age.

Methods

We conducted an observational study to investigate the association between hypernatremia, eGFR, and age at hospital admission and in-hospital mortality, and discharge dispositions. We analyzed the data of 1.9 million patients extracted from the Cerner Health Facts databases (2000-2018). Adjusted multinomial regression models were used to estimate the relationship of hypernatremia to outcomes of hospitalized patients.

Results

Of all hospitalized patients, 3% had serum sodium (Na) >145 mEq/L at hospital admission. Incidence of in-hospital mortality was 12% and 2% in hyper- and normonatremic patients, respectively. The risk of all outcomes increased significantly for Na >155 mEq/L compared with the reference interval of Na=135-145 mEq/L. Odds ratios (95% confidence intervals) for in-hospital mortality and discharge to a hospice or nursing facility were 34.41 (30.59-38.71), 21.14 (17.53-25.5), and 12.21 (10.95-13.61), respectively (all P<0.001). In adjusted models, we found that the association between Na and disposition was modified by eGFR (P<0.001) and by age (P<0.001). Sensitivity analyses were performed using the eGFR equation without race as a covariate, and the inferences did not substantially change. In all hypernatremic groups, patients aged 76-89 and ≥90 had higher odds of in-hospital mortality compared with younger patients (all P<0.001).

Conclusions

Hypernatremia was significantly associated with in-hospital mortality and discharge to a hospice or nursing facility. The risk of in-hospital mortality and other outcomes was highest among those with Na >155 mEq/L. This work demonstrates that hypernatremia is an important factor related to discharge disposition and supports the need to study whether protocolized treatment of hypernatremia improves outcomes.

Bacteraemia and quick Sepsis Related Organ Failure Assessment (qSOFA) are independent risk factors for long-term mortality in very elderly patients with suspected infection: retrospective cohort study

Background

In older adult patients, bloodstream infections cause significant mortality. However, data on long-term prognosis in very elderly patients are scarce. This study aims to assess 1-year mortality from bacteraemia in very elderly patients.

Methods

Retrospective cohort study in inpatients aged 80 years or older and suspected of having sepsis. Patients with (n = 336) and without (n = 336) confirmed bacteraemia were matched for age, sex, and date of culture, and their characteristics were compared. All-cause mortality and risk of death were assessed using the adjusted hazard ratio (aHR).

Results

Compared to controls, cases showed a higher 1-year mortality (34.8% vs. 45.2%) and mortality rate (0.46 vs. 0.69 deaths per person-year). Multivariable analysis showed significant risk of 1-year mortality in patients with bacteraemia (aHR: 1.31, 95% confidence interval [CI] 1.03–1.67), quick Sepsis Related Organ Failure Assessment (qSOFA) score of 2 or more (aHR: 2.71, 95% CI 2.05–3.57), and age of 90 years or older (aHR 1.53, 95% CI 1.17–1.99).

Conclusions

In elderly patients suspected of sepsis, bacteraemia is associated with a poor prognosis and higher long-term mortality. Other factors related to excess mortality were age over 90 years and a qSOFA score of 2 or more.

Serum sodium on admission affects postoperative in-hospital mortality in acute aortic dissection patients

Background

Acute aortic dissection (AAD) is very fatal without surgical treatment. Higher serum sodium can increase in-hospital mortality of many diseases; however, the effect of serum sodium on postoperative in-hospital mortality in AAD patients remains unknown.

Methods

We collected a total of 415 AAD patients from January 2015 to December 2019. Patients were classified into four categories (Q1-Q4) according to the admission serum sodium quartile. The cox proportional hazards model evaluated the association between serum sodium and in-hospital mortality. All-cause in-hospital mortality was set as the endpoint.

Results

By adjusting many covariates, cox proportional hazards model revealed the in-hospital mortality risk of both Q3 and Q4 groups was 3.086 (1.242–7.671, P = 0.015) and 3.370 (1.384–8.204, P = 0.007) respectively, whereas the risk of Q2 group was not significantly increased. Univariate and multiple Cox analysis revealed that Stanford type A, serum glucose, α-hydroxybutyrate dehydrogenase and serum sodium were risk factors correlated with in-hospital death in AAD patients.

Conclusion

The study indicates that the admission serum sodium of AAD patients has a vital impact on postoperative hospital mortality.

Dysnatremias in Chronic Kidney Disease: Pathophysiology, Manifestations, and Treatment

The decreased ability of the kidney to regulate water and monovalent cation excretion predisposes patients with chronic kidney disease (CKD) to dysnatremias. In this report, we describe the clinical associations and methods of management of dysnatremias in this patient population by reviewing publications on hyponatremia and hypernatremia in patients with CKD not on dialysis, and those on maintenance hemodialysis or peritoneal dialysis. The prevalence of both hyponatremia and hypernatremia has been reported to be higher in patients with CKD than in the general population. Certain features of the studies analyzed, such as variation in the cut-off values of serum sodium concentration ([Na]) that define hyponatremia or hypernatremia, create comparison difficulties. Dysnatremias in patients with CKD are associated with adverse clinical conditions and mortality. Currently, investigation and treatment of dysnatremias in patients with CKD should follow clinical judgment and the guidelines for the general population. Whether azotemia allows different rates of correction of [Na] in patients with hyponatremic CKD and the methodology and outcomes of treatment of dysnatremias by renal replacement methods require further investigation. In conclusion, dysnatremias occur frequently and are associated with various comorbidities and mortality in patients with CKD. Knowledge gaps in their treatment and prevention call for further studies.

Hypernatremia subgroups among hospitalized patients by machine learning consensus clustering with different patient survival

BACKGROUND

The objective of this study was to characterize hypernatremia patients at hospital admission into clusters using an unsupervised machine learning approach and to evaluate the mortality risk among these distinct clusters.

METHODS

We performed consensus cluster analysis based on demographic information, principal diagnoses, comorbidities, and laboratory data among 922 hospitalized adult patients with admission serum sodium of > 145 mEq/L. We calculated the standardized difference of each variable to identify each cluster's key features. We assessed the association of each hypernatremia cluster with hospital and 1-year mortality.

RESULTS

There were three distinct clusters of patients with hypernatremia on admission: 318 (34%) patients in cluster 1, 339 (37%) patients in cluster 2, and 265 (29%) patients in cluster 3. Cluster 1 consisted of more critically ill patients with more severe hypernatremia and hypokalemic hyperchloremic metabolic acidosis. Cluster 2 consisted of older patients with more comorbidity burden, body mass index, and metabolic alkalosis. Cluster 3 consisted of younger patients with less comorbidity burden, higher baseline eGFR, hemoglobin, and serum albumin. Compared to cluster 3, odds ratios for hospital mortality were 15.74 (95% CI 3.75-66.18) for cluster 1, and 6.51 (95% CI 1.48-28.59) for cluster 2, whereas hazard ratios for 1-year mortality were 6.25 (95% CI 3.69-11.46) for cluster 1 and 4.66 (95% CI 2.73-8.59) for cluster 2.

CONCLUSION

Our cluster analysis identified three clinically distinct phenotypes with differing mortality risk in patients hospitalized with hypernatremia.

Increased short-term and long-term mortality in community- and hospital-acquired hypernatraemia and in patients with delayed serum sodium correction

BACKGROUND

This study examined the short-term and long-term mortality of community- and hospital-acquired hypernatraemia in a large cohort of general hospitalised patients, and the impact of delayed serum sodium correction in hypernatraemic patients.

METHODS

Adult patients admitted to Mayo Clinic Rochester from 2011 to 2013 were examined. The patients with admission serum sodium ≥138 mEq/L and at least 2 serum sodium measurements during hospitalisation were included. Hypernatraemia was defined as serum sodium ≥143 mEq/L. The patients were categorised into three groups based on serum sodium at admission and during hospitalisation: (a) normal serum sodium, (b) community-acquired hypernatraemia and (c) hospital-acquired hypernatraemia. Outcomes included hospital mortality and 1-year mortality after hospital discharge amongst hospital survivors.

RESULTS

Of 25 781 eligible patients, 45% had normal serum sodium, 20% had community-acquired hypernatraemia and 35% had hospital-acquired hypernatraemia. In adjusted analysis, odds ratios (ORs) of community- and hospital-acquired hypernatraemia for hospital mortality were 4.91 (95% CI 3.47-6.94) and 4.11 (95% CI 2.94-5.73), whereas hazard ratio (HR) for 1-year mortality was 1.76 (95% CI 1.56-1.98) and 1.61 (95% CI 1.45-1.79), respectively. Hospital-acquired hypernatraemia had a higher hospital mortality but not 1-year mortality than community-acquired hypernatraemia. In patients with community-acquired hypernatraemia, 36% remained hypernatraemic by hospital day 3. Hospital mortality (OR 3.01; 95% CI 2.71-5.83) and 1-year mortality (HR 1.51; 95% CI 1.26-1.81) were significantly increased in patients with persistent hypernatraemia, compared with those with serum sodium correction into optimal range of 138-142 mEq/L.

CONCLUSION

Hypernatraemia, regardless of acquisition origin, is associated with elevated short-term and long-term mortality. Hospital-acquired hypernatraemia was more common and had a higher short-term mortality than community-acquired hypernatraemia. Failure to correct hypernatraemia by hospital day 3 is associated with increased mortality.

Fluid-induced harm in the hospital: look beyond volume and start considering sodium. From physiology towards recommendations for daily practice in hospitalized adults

PURPOSE

Iatrogenic fluid overload is a potential side effect of intravenous fluid therapy in the hospital. Little attention has been paid to sodium administration as a separate cause of harm. With this narrative review, we aim to substantiate the hypothesis that a considerable amount of fluid-induced harm is caused not only by fluid volume, but also by the sodium that is administered to hospitalized patients.

METHODS

We show how a regular dietary sodium intake is easily surpassed by the substantial amounts of sodium that are administered during typical hospital stays. The most significant sodium burdens are caused by isotonic maintenance fluid therapy and by fluid creep, defined as the large volume unintentionally administered to patients in the form of dissolved medication. In a section on physiology, we elaborate on the limited renal handling of an acute sodium load. We demonstrate how the subsequent retention of water is an energy-demanding, catabolic process and how free water is needed to excrete large burdens of sodium. We quantify the effect size of sodium-induced fluid retention and discuss its potential clinical impact. Finally, we propose preventive measures, discuss the benefits and risks of low-sodium maintenance fluid therapy, and explore options for reducing the amount of sodium caused by fluid creep.

CONCLUSION

The sodium burdens caused by isotonic maintenance fluids and fluid creep are responsible for an additional and avoidable derailment of fluid balance, with presumed clinical consequences. Moreover, the handling of sodium overload is characterized by increased catabolism. Easy and effective measures for reducing sodium load and fluid retention include choosing a hypotonic rather than isotonic maintenance fluid strategy (or avoiding these fluids when enough free water is provided through other sources) and dissolving as many medications as possible in glucose 5%.

Increased mortality risk associated with serum sodium variations and borderline hypo- and hypernatremia in hospitalized adults

Background

This study aimed to evaluate short-term and long-term mortalities in a cohort of unselected hospitalized patients with serum sodium concentration ([Na⁺]) variations within and outside of reference range.

Methods

All adult patients admitted to the Mayo Clinic, Rochester, MN, USA from January 2011 to December 2013 (n = 147358) were retrospectively screened. Unique patients admitted during the study period were examined. The main exposure was serum [Na⁺] variation. Outcome measures were hospital and 1-year all-cause mortalities.

Results

A total of 60944 patients, mean age 63 ± 17 years, were studied. On admission, 17% (n = 10066) and 1.4% (n = 852) had hypo- and hypernatremia, respectively. During the hospital stay, 11044 and 4128 developed hypo- and hypernatremia, respectively, accounting for 52.3 and 82.9% of the total hypo- and hypernatremic patients. Serum [Na⁺] variations of ≥6 mEq/L occurred in 40.6% (n = 24 740) of the 60 944 patients and were significantly associated with hospital and 1-year mortalities after adjusting potential confounders (including demographics, comorbidities, estimated glomerular filtration rate, admission serum [Na⁺], number of [Na⁺] measurements and length of hospital stay). Adjusted odds ratios for hospital and 1-year mortalities increased with increasing [Na⁺] variations in a dose-dependent manner, from 1.47 to 5.48 (all 95% confidence intervals >1.0). Moreover, in fully adjusted models, [Na⁺] variations (≥6 mEq/L) within the reference range (135–145 mEq/L) or borderline hypo- or hypernatremia (133–137 and 143–147 mEq/L, respectively) compared with 138–142 mEq/L were associated with increased hospital and 1-year mortalities.

Conclusion

In hospitalized adults, [Na⁺] fluctuation (≥6 mEq/L) irrespective of admission [Na⁺] and borderline hypo- or hypernatremia are independent predictors of progressively increasing short- and long-term mortality burdens.

Hypernatremia and moderate-to-severe hyponatremia are independent predictors of mortality in septic patients at emergency department presentation: A sub-group analysis of the need-speed trial

STUDY OBJECTIVE

Early risk stratification of septic patients presenting to the emergency department (ED) is challenging. The aim of the study was to evaluate the prognostic role of plasmatic sodium level (_PNa⁺) derangements at ED presentation in septic patients.

METHODS

According to _PNa⁺ at ED presentation patients were divided in eunatremic (136-145 mEq/L), hypernatremic (>145 mEq/L) and hyponatremic (<136 mEq/L). Hyponatremic patients were subsequently divided in mild (130-135 mEq/L), moderate (125-129 mEq/L) and severe (<125 mEq/L). 7 and 30-day mortality was evaluated according to _PNa⁺ derangements and the degree of hyponatremia. The same analysis was then performed only in respiratory tract infection-related (RTI-r) sepsis patients.

RESULTS

879 septic patients were included in this analysis, 40.3% had hyponatremia, 5.7% hypernatremia. Hypernatremia showed higher mortality rates at both endpoints compared to eunatremia and hyponatremia (p<0.0001 for both). Eunatremia and mild hyponatremia were compared vs. moderate-to-severe hyponatremia showing a significant difference in terms of 7 and 30-day survival (p = 0.004 and p = 0.007, respectively). The Cox proportional model identified as independent predictors of 7 and 30-day mortality moderate-to-severe hyponatremia (HR 4.89[2.38-10.03] and 1.79[1.07-3.01], respectively) and hypernatremia (HR 3.52[1.58-7.82] and 2.14[1.17-3.92], respectively). The same analysis was performed in patients with respiratory tract infection-related sepsis (n = 549), with similar results.

CONCLUSION

Both hypernatremia and moderate-to-severe hyponatremia at ED presentation independently predict mortality in septic patients, allowing early risk stratification and suggesting more aggressive therapeutic strategies.

The prognostic importance of serum sodium levels at hospital discharge and one-year mortality among hospitalized patients

BACKGROUND

The optimal range of serum sodium at hospital discharge is unclear. Our objective was to assess the one-year mortality based on discharge serum sodium in hospitalized patients.

METHODS

We analyzed a cohort of hospitalized adult patients between 2011 and 2013 who survived hospital admission at a tertiary referral hospital. We categorized discharge serum sodium into five groups; ≤132, 133-137, 138-142, 143-147, and ≥148 mEq/L. We assessed one-year mortality risk after hospital discharge based on discharge serum sodium, using discharge sodium of 138-142 mEq/L as the reference group.

RESULTS

Of 55 901 eligible patients, 4.9%, 29.8%, 56.1%, 8.9%, 0.3% had serum sodium of ≤132, 133-137, 138-142, 143-147, and ≥148 mEq/L, respectively. We observed a U-shaped association between discharge serum sodium and one-year mortality, with nadir mortality in discharge serum sodium of 138-142 mEq/L. When adjusting for potential confounders, including admission serum sodium, one-year mortality was significantly higher in both discharge serum sodium ≤137 and ≥143 mEq/L, compared with discharge serum sodium of 138-142 mEq/L. The mortality risk was the most prominent in elevated discharge serum sodium of ≥148 mEq/L (HR 3.86; 95% CI 3.05-4.88), exceeding the risk associated with low discharge serum sodium of ≤132 mEq/L (HR 1.43; 95% CI 1.30-1.57).

CONCLUSION

The optimal range of serum sodium at discharge was 138-142 mEq/L. Both hypernatremia and hyponatremia at discharge were associated with higher one-year mortality. The impact on higher one-year mortality was more prominent in hypernatremia than hyponatremia.

Progression to Severe Hypernatremia in Hospitalized General Medicine Inpatients: An Observational Study of Hospital-Acquired Hypernatremia

Background and objectives: Hypernatremia can be community or hospital-acquired, and there may be specific factors unique to the hospital environment, such as intravenous fluid treatment, which contribute to hypernatremia. The aim of this study was to determine the factors associated with the progression from moderate to severe hospital-acquired hypernatremia among patients admitted under general medicine. Materials and Methods: In this retrospective, single-center cohort study (2012 to 2017), we used ICD-10 coding and medical records to identify adult patients who developed moderate hypernatremia and followed them for progression to severe hypernatremia. We profiled the serum biochemistry and the volume and composition of prescribed intravenous fluids. We applied logistic regression to determine the factors associated with the progression to severe hypernatremia, using the patients with moderate hypernatremia as reference. Results: Of the 180 medical inpatients (median age of 81 years) with moderate hospital-acquired hypernatremia, 9.4% progressed to severe hypernatremia. Normal saline comprised 76% of intravenous fluid volume administered prior to onset of moderate hypernatremia. After the onset, 38% of fluid volume prescribed remained normal saline. The factors independently associated with progression to severe hypernatremia included chronic kidney disease stage (odds ratio 2.38, 95% CI: 1.26-4.50, P = 0.008) and serum creatinine increase (per 10 µmol/L, OR 1.29, 95% CI: 1.07-1.57, P = 0.009). Conclusions: Patients with chronic kidney disease and acute kidney injury may have an increased risk of severe hospital-acquired hypernatremia.

Trajectories of Serum Sodium on In-Hospital and 1-Year Survival among Hospitalized Patients

BACKGROUND AND OBJECTIVES

This study aimed to investigate the association between in-hospital trajectories of serum sodium and risk of in-hospital and 1-year mortality in patients in hospital.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This is a single-center cohort study. All adult patients who were hospitalized from years 2011 through 2013 who had available admission serum sodium and at least three serum sodium measurements during hospitalization were included. The trend of serum sodium during hospitalization was analyzed using group-based trajectory modeling; the five main trajectories were grouped as follows: (1) stable normonatremia, (2) uncorrected hyponatremia, (3) borderline high serum sodium, (4) corrected hyponatremia, and (5) fluctuating serum sodium. The outcome of interest was in-hospital mortality and 1-year mortality. Stable normonatremia was used as the reference group for outcome comparison.

RESULTS

A total of 43,539 patients were analyzed. Of these, 47% had stable normonatremia, 15% had uncorrected hyponatremia, 31% had borderline high serum sodium, 3% had corrected hyponatremia, and 5% had fluctuating serum sodium trajectory. In adjusted analysis, there was a higher in-hospital mortality among those with uncorrected hyponatremia (odds ratio [OR], 1.33; 95% CI, 1.06 to 1.67), borderline high serum sodium (OR, 1.66; 95% CI, 1.38 to 2.00), corrected hyponatremia (OR, 1.50; 95% CI, 1.02 to 2.20), and fluctuating serum sodium (OR, 4.61; 95% CI, 3.61 to 5.88), compared with those with the normonatremia trajectory. One-year mortality was higher among those with uncorrected hyponatremia (hazard ratio [HR], 1.28; 95% CI, 1.19 to 1.38), borderline high serum sodium (HR, 1.18; 95% CI, 1.11 to 1.26), corrected hyponatremia (HR, 1.24; 95% CI, 1.08 to 1.42), and fluctuating serum sodium (HR, 2.10; 95% CI, 1.89 to 2.33) compared with those with the normonatremia trajectory.

CONCLUSIONS

More than half of patients who had been hospitalized had an abnormal serum sodium trajectory during hospitalization. This study demonstrated that not only the absolute serum sodium levels but also their in-hospital trajectories were significantly associated with in-hospital and 1-year mortality. The highest in-hospital and 1-year mortality risk was associated with the fluctuating serum sodium trajectory.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2020_03_25_CJN.12281019.mp3.

Hyperchloremia, not Concomitant Hypernatremia, Independently Predicts Early Mortality in Critically Ill Moderate-Severe Traumatic Brain Injury Patients

BACKGROUND

Hypernatremia has been associated with mortality in neurocritically ill patients, with and without traumatic brain injury (TBI). These studies, however, lack concomitant adjustment for hyperchloremia as a physiologically co-occurring finding despite the associations with hyperchloremia and worse outcomes after trauma, sepsis, and intracerebral hemorrhage. The objective of our study was to examine the association of concomitant hypernatremia and hyperchloremia with in-hospital mortality in moderate-severe TBI (msTBI) patients.

METHODS

We retrospectively analyzed prospectively collected data from the OPTIMISM-study and included all msTBI patients consecutively enrolled between 11/2009 and 1/2017. Time-weighted average (TWA) sodium and chloride values were calculated for all patients to examine the unadjusted mortality rates associated with the burden of hypernatremia and hyperchloremia over the entire duration of the intensive care unit stay. Multivariable logistic regression modeling predicting in-hospital mortality adjusted for validated confounders of msTBI mortality was applied to evaluate the concomitant effects of hypernatremia and hyperchloremia. Internal bootstrap validation was performed.

RESULTS

Of the 458 patients included for analysis, 202 (44%) died during the index hospitalization. Fifty-five patients (12%) were excluded due to missing data. Unadjusted mortality rates were nearly linearly increasing for both TWA sodium and TWA chloride, and were highest for patients with a TWA sodium > 160 mmol/L (100% mortality) and TWA chloride > 125 mmol/L (94% mortality). When evaluated separately in the multivariable analysis, TWA sodium (per 10 mmol/L change: adjusted OR 4.0 [95% CI 2.1-7.5]) and TWA chloride (per 10 mmol/L change: adjusted OR 3.9 [95% CI 2.2-7.1]) independently predicted in-hospital mortality. When evaluated in combination, TWA chloride remained independently associated with in-hospital mortality (per 10 mmol/L change: adjusted OR 2.9 [95% CI 1.1-7.8]), while this association was no longer observed with TWA sodium values (per 10 mmol/L change: adjusted OR 1.5 [95% CI 0.51-4.4]).

CONCLUSIONS

When concomitantly adjusting for the burden of hyperchloremia and hypernatremia, only hyperchloremia was independently associated with in-hospital mortality in our msTBI cohort. Pending validation, our findings may provide the rationale for future studies with targeted interventions to reduce hyperchloremia and improve outcomes in msTBI patients.

Effect of acute hypernatremia induced by hypertonic saline administration on endothelial glycocalyx in rabbits

BACKGROUND AND OBJECTIVE

The endothelial glycocalyx (EG) is fragile and sensitive to damage such as exposure to hypernatremia. Our aim was to describe the influence of hypernatremia on the EG in sublingual and brain microcirculation in rabbits.

METHODS

Hypernatremia was induced by intravenous administration of 10% NaCl solution. The sublingual and brain microcirculation were evaluated by the Side-stream Dark Field imaging before (T1) and 20 minutes after infusion of 10% saline (T2). Damage to the EG was quantified by automated analysis of Perfused Boundary Region (PBR) indicating the amount of penetration of red blood cells into the EG. Syndecan-1 levels were also measured.

RESULTS

Hypernatremia was reached in all 20 animals, the PBR values of the sublingual area raised from 1,98 (0,3) to 2,17 (0,18) μm (p = 0,05). The levels of syndecan-1 (1,23 (0,36); 1,31 (0,33) ng/l, p = 0,3) did not mirror PBR changes.

CONCLUSIONS

Hypernatremia increased the PBR within the sublingual microcirculation in our animal model, probably due to compression of the EG related to temporary intravascular hypervolemia and changes of the EG charge in RBC instead of direct damaging effect on EG, which has been excluded by rather unchanged levels of syndecan-1.

Predictive Factors and Microbial Spectrum for Infectious Complications after Hepatectomy with Cholangiojejunostomy in Perihilar Cholangiocarcinoma

Background: Despite advances in surgical techniques and peri-operative management, post-operative infectious complications still are common after perihilar cholangiocarcinoma (PHCC). This study investigated the predictive factors and microbial spectrum for infections after hepatectomy with cholangiojejunostomy performed to treat PHCC. Methods: A total of 70 consecutive patients, who underwent hepatectomy with cholangiojejunostomy by the same surgeons at a tertiary referral medical center between September 2010 and January 2019, were enrolled. Clinical data were reviewed for multivariable analysis to find independent risk factors for infectious complications. Microorganisms isolated from bile and infection sites were counted to explore the microbial spectrum. Results: A total of 43 patients (61.4%) suffered post-operative infections (33 with surgical site infection [SSI], four with bacteremia, three with pneumonia, 10 with cholangitis, and two with fungus infectious stomatitis), and 28 of them (65.1%) had a positive bile culture. Four independent risk factors were identified: male sex (odds ratio [OR] 12.737; 95% confidence interval [CI] 2.298-70.611; p = 0.004), red blood cell (RBC) count <3.8 × 10¹²/L (OR 5.085; 95% CI 1.279-20.211; p = 0.021), total cholesterol (TC) <2.90 mmol/L (OR 5.715; 95% CI 1.534-21.299; p = 0.009), and serum Na⁺ >145 mmol/L (OR 10.387; 95% CI 1.559-69.201; p = 0.016) on post-operative day (POD) 1. A total of 217 and 196 microorganisms were cultured from 311 and 627 specimens, respectively, collected from pre-/intra-operative bile and possible infection sites. Staphylococcus, Enterococcus, Acinetobacter, Streptococcus, and Escherichia were the most common findings of bile culture. The first five organisms most frequently isolated from infection sites were Enterococcus, Staphylococcus, Klebsiella, Acinetobacter, and Candida. A total of 18 patients (64.3%) had at least one species isolated from infection sites that had appeared in a previous bile culture. Conclusions: Male sex, erythrocytopenia, hypocholesterolemia, and hypernatremia on POD 1 are independent risk factors for infectious complications. For patients without positive bile cultures, third-generation cephalosporins could be considered as the prophylactic antibiotic. It is important to monitor the pathogens throughout the hospital stay.

Electrolyte imbalances in an unselected population in an emergency department: A retrospective cohort study

BACKGROUND

Although electrolyte imbalances (EIs) are common in the emergency department (ED), few studies have examined the occurrence of such conditions in an unselected population.

OBJECTIVES

To investigate the frequency of EI among adult patients who present to the ED, with regards to type and severity, and the association with age and sex of the patient, hospital length of stay (LOS), readmission, and mortality.

METHODS

A retrospective cohort study. All patients ≥18 years referred for any reason to the ED between January 1, 2010, and December 31, 2015, who had measured blood electrolytes were included. In total, 62 991 visits involving 31 966 patients were registered.

RESULTS

EIs were mostly mild, and the most common EI was hyponatremia (glucose-corrected) (24.6%). Patients with increasing severity of EI had longer LOS compared with patients with normal electrolyte measurements. Among all admitted patients, there were 12928 (20.5%) readmissions within 30 days from discharge during the study period. Hyponatremia (glucose-corrected) was associated with readmission, with an adjusted odds ratio (OR) of 1.25 (95% CI, 1.18-1.32). Hypomagnesemia and hypocalcemia (albumin-corrected) were also associated with readmission, with ORs of 1.25 (95% CI, 1.07-1.45) and 1.22 (95% CI, 1.02-1.46), respectively. Dysnatremia, dyskalemia, hypercalcemia, hypermagnesemia, and hyperphosphatemia were associated with increased in-hospital mortality, whereas all EIs except hypophosphatemia were associated with increased 30-day and 1-year mortality.

CONCLUSIONS

EIs were common and increasing severity of EIs was associated with longer LOS and increased in-hospital, 30-days and 1-year mortality. EI monitoring is crucial for newly admitted patients, and up-to-date training in EI diagnosis and treatment is essential for ED physicians.

Osmotic stress and mortality in elderly patients with kidney failure: a retrospective study

Purpose

Water balance disorders are associated with a high risk of death in elderly patients. The role of osmotic stress intensity and its direction toward hypo- or hypernatremia is a matter of controversy regarding patients’ survival. The aims of this study were, first, to measure the frequency of cellular hydration disorders in patients over 75 years old hospitalized in nephrology department for reversible acute renal failure, and second, to compare the impact of hyperhydration and hypohydration on the risk of death at 6 months.

Patients and methods

We retrospectively studied the data of 279 patients with chronic kidney disease (CKD), aged 75 years or older, with pre-renal azotemia who experienced dysnatremia. We classified them according to natremia levels and compared their outcome in univariate and multivariate analysis.

Results

The patients were on average 83.2±5.4 years old. Among them, 128 were normonatremic, 82 were hyponatremic and 69 were hypernatremic. Osmotic stress intensity appreciated by the variation rate of natremia did not differ significantly between hyper- and hyponatremic patients. Patients had CKD stage 3B and 4 with acute kidney injury (AKI) of different severities. We observed that only hypernatremia was linked to death in the first 6 months following hospital discharge.

Conclusion

Hypernatremia is a strong predictor of fatal outcome in elderly patients suffering from chronic kidney impairment and referred for pre-renal azotemia.

Hypernatremia is associated with poorer outcomes following aneurysmal subarachnoid hemorrhage: a nationwide inpatient sample analysis

BACKGROUND

Hypernatremia is one of the most common electrolyte disturbances following aneurysmal subarachnoid hemorrhage (aSAH) and has been correlated with increased mortality in single institution studies. We investigated this association using a large nationwide healthcare database.

METHODS

We performed a retrospective analysis of adults between 2002 and 2011 with a primary diagnosis of aSAH using the Nationwide Inpatient Sample (NIS). Patients were grouped according to whether or not an inpatient diagnosis of hypernatremia was present. The primary outcome was the NIS-SAH outcome measure. Secondary outcomes included in-hospital mortality, length of stay (LOS), and non-routine hospital discharge. Outcomes analyses adjusted for SAH severity using the NIS-SAH Severity Score, Charlson Comorbidity Index, and the presence of cerebral edema.

RESULTS

A total of 18,377 patients were included in the study. The incidence of a poor outcome as defined by the NIS-SAH outcome measure was 65.9% in the hypernatremia group and 33.4% in the normonatremia group (OR 1.96, 95% CI 1.68 - 2.27). There was higher mortality in the hypernatremia group (OR 1.60, 95% CI 1.37 - 1.87). Patients with hypernatremia had a significantly higher rate of non-routine hospital discharge and gastrostomy. The incidences of poor outcome, in-hospital mortality, and non-routine disposition were higher in the hypernatremia group regardless of treatment type (clipping vs. endovascular embolization). Pulmonary complications and acute kidney injury were more common in the hypernatremia group as well.

CONCLUSIONS

In patients with aSAH, hypernatremia is associated with poorer functional outcomes regardless of SAH severity.