Updates in hyponatremia and hypernatremia.

PURPOSE OF REVIEW: Hyponatremia and hypernatremia are commonly encountered electrolyte abnormalities that require timely and careful intervention, as they can be associated with significant morbidity and mortality. RECENT FINDINGS: This review article addresses the etiology, presentation, diagnosis, and management of both hyponatremia and hypernatremia, emphasizing the latest advancements and emerging trends in pediatric care. SUMMARY: A methodical approach is needed to accurately assess and treat hyponatremia and hypernatremia. Both conditions continue to rely on serum and urine testing, however newer tests such as copeptin and stimulated testing may hold promise to further refine testing in the future.

Challenges in using fractional excretion of sodium in the assessment of salt poisoning.

AIM: Hypernatraemia typically reflects dehydration, yet in rare instances may be caused by salt poisoning. Identifying these rare cases is a difficult challenge. Making the diagnosis of salt poisoning can have severe consequences, such as the removal of the child from its home or even prison sentences for the implicated carer. It is therefore imperative to get the diagnosis right. Guidelines for the assessment of hypernatraemia emphasise the importance of the fractional excretion of sodium to distinguish between dehydration and salt poisoning, but no generally accepted cut-off value exists. Opinions about the diagnosis of salt poisoning in some cases consequently may differ. Here, we aim to highlight the challenges and stimulate discussion on how to improve the tools for the assessment of hypernatraemia. METHODS: Report of a case of unexplained hypernatraemia in which the treating paediatrician raised the suspicion of salt poisoning. RESULTS: Two consulted experts made opposing judgements about the aetiology of the observed hypernatraemia. CONCLUSION: Clear diagnostic criteria for the diagnosis of salt poisoning are lacking and more data are needed for their establishment. Without this, victims may experience further harm and carers are at risk of devastating, yet potentially erroneous accusations.

A retrospective cohort study on the clinical outcomes of patients admitted to intensive care units with dysnatremia.

With evolving patient characteristics and patterns of ICU utilization, the impact of dysnatremias on patient outcomes and healthcare costs in the present era have not been well studied. Patients ≥ 18 years admitted to the ICUs in public hospitals in Hong Kong between January 2010 and June 2022 and had at least one serum sodium measurement obtained within 24 h prior to or following ICU admission were stratified into normonatremic (135-145 mmol/L), hyponatremic (< 135 mmol/L) and hypernatremic (> 145 mmol/L) groups. A total of 162,026 patients were included-9098 (5.6%), 40,533 (25.0%) and 112,395 (69.4%) patients were hypernatremic, hyponatremic and normonatremic at the time of ICU admission, respectively. The odds of patients with hypernatremia and hyponatremia dying in the ICU were 27% and 14% higher (aOR 1.27, 95% CI 1.19-1.36 and aOR 1.14, 95% CI 1.08-1.19, respectively; P < 0.001 for both), and 52% and 21% higher for dying in the hospital (aOR 1.52, 95% CI 1.43-1.62 and aOR 1.21, 95% CI 1.17-1.26, respectively; P < 0.001 for both] compared with those with normonatremia. Patients with dysnatremia also had longer ICU length of stay (LOS), hospital LOS, and higher healthcare costs than the normonatremic group. Dysnatremias at ICU admission were associated with increased ICU and in-hospital mortality and overall healthcare burden.

Diagnosis and Management of Sodium Disorders: Hyponatremia and Hypernatremia.

Hyponatremia and hypernatremia are electrolyte disorders that can be associated with poor outcomes. Hyponatremia is considered mild when the sodium concentration is 130 to 134 mEq per L, moderate when 125 to 129 mEq per L, and severe when less than 125 mEq per L. Mild symptoms include nausea, vomiting, weakness, headache, and mild neurocognitive deficits. Severe symptoms of hyponatremia include delirium, confusion, impaired consciousness, ataxia, seizures, and, rarely, brain herniation and death. Patients with a sodium concentration of less than 125 mEq per L and severe symptoms require emergency infusions with 3% hypertonic saline. Using calculators to guide fluid replacement helps avoid overly rapid correction of sodium concentration, which can cause osmotic demyelination syndrome. Physicians should identify the cause of a patient's hyponatremia, if possible; however, treatment should not be delayed while a diagnosis is pursued. Common causes include certain medications, excessive alcohol consumption, very low-salt diets, and excessive free water intake during exercise. Management to correct sodium concentration is based on whether the patient is hypovolemic, euvolemic, or hypervolemic. Hypovolemic hyponatremia is treated with normal saline infusions. Treating euvolemic hyponatremia includes restricting free water consumption or using salt tablets or intravenous vaptans. Hypervolemic hyponatremia is treated primarily by managing the underlying cause (e.g., heart failure, cirrhosis) and free water restriction. Hypernatremia is less common than hyponatremia. Mild hypernatremia is often caused by dehydration resulting from an impaired thirst mechanism or lack of access to water; however, other causes, such as diabetes insipidus, are possible. Treatment starts with addressing the underlying etiology and correcting the fluid deficit. When sodium is severely elevated, patients are symptomatic, or intravenous fluids are required, hypotonic fluid replacement is necessary.

[Hypernatremia in hospital]. / Hypernatrémie en milieu hospitalier.

Hypernatremia, defined as a serum sodium concentration greater than 145 mmol/l, is an electrolyte disorder associated with increased in-hospital morbidity and mortality. Its prevalence is estimated between 1 to 3% in hospitalized patients and up to 11% in intensive care. It most often results from an impaired thirst mechanism or the inability to access water to drink. The clinical presentation varies depending on the severity of the hypernatremia. Patients may be pauci-symptomatic to comatose. Correcting too quickly the hypernatremia can lead to serious consequences (cerebral hemorrhage, demyelination). Prevention of the onset of hypernatremia is essential in the hospital. Its management consists of treating the underlying cause and correcting the hyperosmolarity by ensuring close monitoring of the sodium level.

L'hypernatrémie, définie par une concentration en sodium dans le sang supérieur à 145 mmol/l, est un trouble électrolytique associé à une morbimortalité hospitalière accrue. Sa prévalence est estimée entre 1 et 3 % chez les patients hospitalisés et jusqu'à 11 % aux soins intensifs. Elle résulte le plus souvent d'une altération du mécanisme de la soif ou d'une incapacité d'accès à l'eau. La présentation clinique varie en fonction de la sévérité de l'hypernatrémie. Les patients peuvent être paucisymptomatiques jusqu'à devenir comateux. Sa correction trop rapide peut engendrer des conséquences dévastatrices (hémorragies cérébrales, démyélinisation). La prévention de son apparition est essentielle à l'hôpital. Sa prise en charge consiste à traiter l'étiologie et corriger l'hyperosmolarité en assurant un suivi rapproché de la natrémie.

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.

Enteral free water vs. parenteral dextrose 5% in water for the treatment of hypernatremia in the intensive care unit: a retrospective cohort study from a mixed ICU.

PURPOSE: Effective treatment options for patients with hypernatremia are limited. Free water administration (parenterally or enterally) is the mainstay of treatment but the impact of each strategy on lowering serum sodium (Na) is not known. The purpose of the study was thus to assess the effectiveness of enteral free water vs. parenteral dextrose 5% in water (D5W) in treating ICU-acquired hypernatremia. METHODS: An electronic medical record-based, retrospective cohort study was conducted in a 30-bed mixed medical-surgical intensive care unit (ICU) in Japan. All adult patients admitted to the ICU from August 2017 to July 2021 were reviewed. After a 2-step exclusion, patients who stayed in the ICU ≥ 24 h and received either or both treatments for ICU-acquired hypernatremia (Na ≥ 145 mEq/L) constituted the study cohort. The primary outcome was a change in serum Na during the 24 h before treatment each day (ΔNa); the secondary outcomes were gastrointestinal complications, serum glucose levels, ICU/hospital mortality, ICU/hospital length of stay, and the duration of mechanical ventilation. Repeated measurements on each patient were addressed using a generalized estimated equation (GEE) for multiple linear regression analysis. Analysis was conducted with R version 4.0.3. RESULTS: In total, 256/6596 (131: D5W, 125: enteral free water) patients were analyzed. Median treatment lasted 6 days [3-17] for the D5W group vs 7 days [3-14] for the enteral free water group with a total median daily treatment volume of 799 [IQR 299-1221] mL vs. 400 [IQR 262-573] mL. GEE multiple linear regression analysis showed an estimated mean ΔNa per liter of treatment fluid of - 2.25 [95% CI - 2.76 to - 1.74] mEq/L per liter of parenteral D5W vs. - 1.91 mEq decrease [95% CI - 2.75 to - 1.07] per liter of enteral free water. Hydrochlorothiazide was the only medication associated with a statistically significant negative ΔNa by- 0.89 [- 1.57 to - 0.21] mEq/L. There were no significant inter-group differences for secondary outcomes. CONCLUSIONS: These results suggest that both enteral free water and parenteral D5W are effective for treating ICU-acquired hypernatremia. Parenteral D5W was slightly more effective than enteral free water to lower serum Na levels in patients with ICU-acquired hypernatremia. TRIAL REGISTRATION: Not applicable.

Dysnatremia and subsequent sodium level changes following various intravenous treatments in infants with acute gastroenteritis.

Acute gastroenteritis is one of the main causes of electrolyte imbalance in infants. We aimed to determine the frequency of and factors associated with dysnatremia at presentation and establish the ideal intravenous treatment scheme. The records of hospitalized infants aged 1-12 months with community-acquired acute gastroenteritis between January 2017 and March 2021 were retrospectively reviewed. Factors associated with dysnatremia at presentation were analyzed by multivariable logistic regression analysis. Subsequent sodium levels 4-24 h after intravenous fluid treatments, which were categorized into 2 groups, were determined in the subgroup of infants with normal sodium levels at presentation. A total of 347 infants with a median age of 8.0 (5.0-10.0) months were included. The frequency of dysnatremia at presentation was 14% (hyponatremia 12% and hypernatremia 2.0%). Severe dehydration was associated with dysnatremia at presentation (p = 0.048). Among 68 infants with normal sodium levels at presentation, the median sodium change was highest in the 5% dextrose in saline group, with changes of + 3 (0.5-5) and + 1 (- 2 to 2) mmol/L in infants who received 5% dextrose in saline and 5% dextrose in 1/3-1/2 saline, respectively (p = 0.001). Four out of 47 infants (8.5%) developed hyponatremia while receiving 5% dextrose in 1/3-1/2 saline. None of those who received 5% dextrose in saline developed subsequent dysnatremia.   Conclusion: The frequency of dysnatremia at presentation among infants with acute gastroenteritis was 14%. Severe dehydration was associated with dysnatremia at presentation, so electrolyte levels need to be assessed in these patients. The use of isotonic solution did not promote acquired dysnatremia. This study supports once more that current guidelines recommending isotonic solution for children, and, especially, infant rehydration, are important also for infants in Thailand. What is Known: • There were a wide variation in the incidence of dysnatremia at presentation in children with acute gastroenteritis in previous pediatric series. • The AAP guidelines recommend using isotonic solution in children with acute illness from 28 days to 18 years of age to prevent acquired hyponatremia. What is New: • The incidence of dysnatremia at presentation in infants with acute gastroenteritis was 14% (hyponatremia 12% and hypernatremia 2.0%). • The use of isotonic solution did not promote acquired dysnatremia in infants with acute gastroenteritis.

Hypokalemia/Hyperkalemia and Hyponatremia/Hypernatremia.

Electrolyte disorders are very common in the pediatric population. Derangements in serum sodium and potassium concentrations are among the most frequently seen given the risk factors and comorbidities unique to children. Pediatricians, in both outpatient and inpatient settings, should be comfortable with the evaluation and initial treatment of disturbances in these electrolyte concentrations. However, to evaluate and treat a child with abnormal serum concentrations of sodium or potassium, it is critical to understand the regulatory physiology that governs osmotic homeostasis and potassium regulation in the body. Comprehension of these basic physiologic processes will allow the provider to uncover the underlying pathology of these electrolyte disturbances and devise an appropriate and safe treatment plan.

Correcting Hypernatremia in Children.

BACKGROUND: In children with hypernatremia, current clinical guidelines recommend a reduction in serum sodium of 0.5 mmol/L per hour or less to avoid complications of cerebral edema. However, no large-scale studies have been conducted in the pediatric setting to inform this recommendation. Therefore, this study aimed to report the association between the rate of correction of hypernatremia, neurological outcomes, and all-cause mortality in children. METHODS: A retrospective cohort study was conducted from 2016 to 2019 at a quaternary pediatric center in Melbourne, Victoria, Australia. All children with at least one serum sodium level ≥150 mmol/L were identified through interrogation of the hospital's electronic medical record. Medical notes, neuroimaging reports, and electroencephalogram results were reviewed for evidence of seizures and/or cerebral edema. The peak serum sodium level was identified and correction rates over the first 24 hours and overall were calculated. Unadjusted and multivariable analyses were used to examine the association between the rate of sodium correction and neurological complications, the requirement for neurological investigation, and death. RESULTS: There were 402 episodes of hypernatremia among 358 children over the 3-year study period. Of these, 179 were community-acquired and 223 developed during admission. A total of 28 patients (7%) died during admission. Mortality was higher in children with hospital-acquired hypernatremia, as was the frequency of intensive care unit admission and hospital length of stay. Rapid correction (>0.5 mmol/L per hour) occurred in 200 children and was not associated with greater neurological investigation or mortality. Length of stay was longer in children who received slow correction (<0.5 mmol/L per hour). CONCLUSIONS: Our study did not find any evidence that rapid sodium correction was associated with greater neurological investigation, cerebral edema, seizures, or mortality; however, slow correction was associated with a longer hospital length of stay.

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.

Delay in desmopressin therapy: Disaster in waiting.

WHAT IS KNOWN AND OBJECTIVE: Central diabetes insipidus (DI) is a complex disease that requires firm adherence to desmopressin therapy. There is little information on the onset of hypernatremia after withdrawal of desmopressin. CASE SUMMARY: We present a case of an elderly woman with central DI whose serum sodium jumped from 141 to 171 mEq/L after 48-72 h of holding oral desmopressin. Her DI crisis resolved with intravenous desmopressin and free water administration. WHAT IS NEW AND CONCLUSION: Based on this precipitous onset of DI crisis, we recommend not withholding desmopressin for more than 24 h.

[Permanent central diabetes insipidus after traumatic brain injury. Case report and literature review]. / Razvitie postoyannogo tsentral'nogo nesakharnogo diabeta posle travmaticheskogo povrezhdeniya golovnogo mozga. Klinicheskii sluchai i obzor literatury.

The authors report permanent central diabetes insipidus (CDI) in a patient after severe traumatic brain injury (TBI) in traffic accident. A 16-year-old boy entered to a medical facility in coma (GCS score 6) with the following diagnosis: acute TBI, severe cerebral contusion, subarachnoid hemorrhage, depressed comminuted cranial vault fracture, basilar skull fracture, visceral contusion. CDI was diagnosed in 3 days after injury considering polyuria and hypernatremia (155 mmol/l). Desmopressin therapy was initiated through a feeding tube. Thirst appeared when a patient came out of the coma after 21 days despite ongoing desmopressin therapy. Considering persistent thirst and polyuria, we continued desmopressin therapy in a spray form. Under this therapy, polyuria reduced to 3-3.5 liters per a day. Symptoms of CDI persisted in long-term period (2 years after TBI) while function of adenohypophysis was intact. This case demonstrates a rare development of permanent diabetes insipidus after TBI. CDI manifested only as polyuria and hypernatremia in coma. Thirst joined after recovery of consciousness. Probable causes of CDI were damage to neurohypophysis and partially injury of pituitary stalk because of extended basilar skull fracture and/or irreversible secondary lesion of hypothalamus following diffuse axonal damage after TBI.