New aspects in the pathogenesis, prevention, and treatment of hyponatremic encephalopathy in children

Evaluation of Hyponatremia in Infants on Vasopressin Therapy

OBJECTIVE

Vasopressin has systemic vasoconstrictive yet pulmonary vasodilatory effects, making it an ideal agent for hypotension management in infants with congenital diaphragmatic hernia (CDH)-associated pulmonary hypertension. The side effects of vasopressin in this population, such as hyponatremia, are understudied. This study aims to characterize the effect of vasopressin on sodium concentrations in infants with and without CDH.

METHODS

This was a retrospective review of patients who received vasopressin while admitted to a level IV neonatal intensive care unit. The primary outcome was the incidence of hyponatremia (blood sodium <135 mmol/L) during vasopressin therapy. Secondary outcomes included time to hyponatremia, dose and duration of vasopressin, incidence of severe hyponatremia (blood sodium <125 mmol/L), and hypertonic saline use. Both blood serum and blood gas sample sodium concentrations were used to compare CDH vs non-CDH patients.

RESULTS

The average difference between baseline and lowest blood sodium was significant for both CDH and non-CDH patients for all samples (p < 0.001). There was no significant difference in the primary outcome, nor in the secondary outcomes of time to hyponatremia or duration of vasopressin infusion. The average dose of vasopressin was higher in the CDH vs non-CDH group (p = 0.018). The incidences of severe hyponatremia and hypertonic saline use were greater in the CDH vs non-CDH group for patients who had blood serum sodium samples collected (p = 0.049 and p = 0.033, respectively).

CONCLUSIONS

This study showed that severe hyponatremia occurred more frequently in CDH vs non-CDH patients. Extreme caution is necessary when managing total body sodium in patients with CDH.

Low Prevalence of Clinically Significant Hyponatremia following Cranial Vault Reconstruction for Single-Suture Craniosynostosis

BACKGROUND

Patients are commonly monitored for hyponatremia after intracranial procedures, yet the prevalence of hyponatremia after cranial vault reconstruction (CVR) remains unclear. The purpose of this study is to define the prevalence, risk factors, and complications of hyponatremia after CVR to optimize postoperative sodium surveillance protocols.

METHODS

Patients with nonsyndromic, single-suture craniosynostosis who underwent primary CVR between 2009 and 2020 at Michigan Medicine were included (n = 231). Demographic, intraoperative, and postoperative characteristics were compared by postoperative hyponatremia status at P < 0.05 significance. Hyponatremia was defined as mild (<135 mEq/L), moderate (<130 mEq/L), or severe (<125 mEq/L) based on the lowest postoperative laboratory draw.

RESULTS

Twenty-three patients (10.0%) developed mild postoperative hyponatremia. No patient developed moderate or severe postoperative hyponatremia. On multivariable regression, decreased preoperative sodium level (P = 0.03) and decreased preoperative weight (P = 0.02) were significantly associated with mild postoperative hyponatremia. No patient developed complications or required hospital readmission because of hyponatremia.

CONCLUSIONS

This large retrospective cohort study of patients with nonsyndromic single-suture craniosynostosis demonstrated a 10% prevalence of mild, clinically inconsequential hyponatremia and 0% prevalence of moderate or severe, clinically significant hyponatremia after primary CVR. Patients with low preoperative sodium level or weight were at increased risk for developing mild postoperative hyponatremia. The results suggest that patients with preoperative sodium greater than 140 mEq/L or preoperative weight greater than 10 kg may be candidates for limited postoperative sodium surveillance; however, future prospective studies are warranted before implementation.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Fluid management in children with volume depletion

Volume depletion is a common condition and a frequent cause of hospitalization in children. Proper assessment of the patient includes a detailed history and a thorough physical examination. Biochemical tests may be useful in selected cases. Understanding the pathophysiology of fluid balance is necessary for appropriate management. A clinical dehydration scale assessing more physical findings may help to determine dehydration severity. Most dehydrated children can be treated orally; however, intravenous therapy may be indicated in patients with severe volume depletion, in those who have failed oral therapy, or in children with altered consciousness or significant metabolic abnormalities. Proper management consists of restoring circulatory volume and electrolyte balance. In this paper, we review clinical aspects, diagnosis, and management of children with volume depletion.

Efficacy and safety of isotonic versus hypotonic intravenous maintenance fluids in hospitalized children: an updated systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Iatrogenic hyponatremia is a common complication following intravenous maintenance fluid therapy (IV-MFT) in hospitalized children. Despite the American Academy of Pediatrics' 2018 recommendations, IV-MFT prescribing practices still vary considerably.

OBJECTIVES

This meta-analysis aimed to compare the safety and efficacy of isotonic versus hypotonic IV-MFT in hospitalized children.

DATA SOURCES

We searched PubMed, Scopus, Web of Science, and Cochrane Central from inception to October 1, 2022.

STUDY ELIGIBILITY CRITERIA

We included randomized controlled trials (RCTs) comparing isotonic versus hypotonic IV-MFT in hospitalized children, either with medical or surgical conditions. Our primary outcome was hyponatremia following IV-MFT. Secondary outcomes included hypernatremia, serum sodium, serum potassium, serum osmolarity, blood pH, blood sugar, serum creatinine, serum chloride, urinary sodium, length of hospital stay, and adverse outcomes.

STUDY APPRAISAL AND SYNTHESIS METHODS

Random-effects models were used to pool the extracted data. We performed our analysis based on the duration of fluid administration (i.e., ≤ 24 and > 24 h). The Grades of Recommendations Assessment Development and Evaluation (GRADE) scale was used to evaluate the strength and level of evidence for recommendations.

RESULTS

A total of 33 RCTs, comprising 5049 patients were included. Isotonic IV-MFT significantly reduced the risk of mild hyponatremia at both ≤ 24 h (RR = 0.38, 95% CI [0.30, 0.48], P < 0.00001; high quality of evidence) and > 24 h (RR = 0.47, 95% CI [0.37, 0.62], P < 0.00001; high quality of evidence). This protective effect of isotonic fluid was maintained in most examined subgroups. Isotonic IV-MFT significantly increased the risk of hypernatremia in neonates (RR = 3.74, 95% CI [1.42, 9.85], P = 0.008). In addition, it significantly increased serum creatinine at ≤ 24 h (MD = 0.89, 95% CI [0.84, 0.94], P < 0.00001) and decreased blood pH (MD = -0.05, 95% CI [-0.08 to -0.02], P = 0.0006). Mean serum sodium, serum osmolarity, and serum chloride were lower in the hypotonic group at ≤ 24 h. The two fluids were comparable in terms of serum potassium, length of hospital stay, blood sugar, and the risk of adverse outcomes.

LIMITATIONS

The main limitation of our study was the heterogeneity of the included studies.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Isotonic IV-MFT was superior to the hypotonic one in reducing the risk of iatrogenic hyponatremia in hospitalized children. However, it increases the risk of hypernatremia in neonates and may lead to renal dysfunction. Given that the risk of hypernatremia is not important even in the neonates, we propose to use balanced isotonic IV-MFT in hospitalized children as it is better tolerated by the kidneys than 0.9% saline.

SYSTEMATIC REVIEW REGISTRATION NUMBER

CRD42022372359. Graphical abstract A higher resolution version of the Graphical abstract is available as Supplementary information.

Postoperative Dysnatremia in Pediatric Patients Undergoing Palatoplasty

OBJECTIVE

Identifying predisposing factors to dysnatremia to improve perioperative care after cleft surgery.

DESIGN

Retrospective case series. Patient data were obtained through the electronic medical records of the hospital.

SETTING

Tertiary care university hospital.

PATIENTS

The inclusion criterion was the measurement of an abnormal natremia value, defined as Na >150 or <130 mmol/l after a cleft lip or cleft palate repair procedure. The exclusion criterion was natremia between 131 and 149 mmol/l.

RESULTS

Natremia measurements were available for 215 patients born between 1995 and 2018. Five patients presented with postoperative dysnatremia. Several predisposing factors to dysnatremia have been identified: drugs, infection, administration of intravenous fluids, and postoperative syndrome of inappropriate antidiuretic hormone secretion. Although the hospital environment contributes to dysnatremia development, the fact that only patients undergoing cleft palate repair develop natremia anomalies suggests that this surgery may be itself a risk factor.

CONCLUSION

Children undergoing palatoplasty may be at higher risk to develop postoperative dysnatremia. Early recognition of symptoms and risk factors, postoperative monitoring, and prompt treatment of dysnatremia diminish the risk of neurological complications.

A unique presentation of hyponatremia and seizures in a 2-month-old child with cystic fibrosis: a case report

Cystic fibrosis is an autosomal recessive disorder that causes a broad range of clinical findings and can present unusually as electrolyte disturbance, such as hyponatremia that causes seizures in children.

CASE PRESENTATION

We report a case of a 2-month-old infant who presented with an episode of grand mal seizure induced by hyponatremia and moderate episodes of milky vomiting after breastfeeding.

CLINICAL DISCUSSION

Proper investigations showed normal cardiac and renal functions. Ultrasonography showed no pathological changes. Laboratory tests performed showed hyponatremia, mild hypokalemia, and hypochloremia. Urinary electrolyte results were normal. While broadening the scope of differential diagnosis in order to reach a final diagnosis, the sweat chloride level was elevated, which confirmed the diagnosis of cystic fibroses.

CONCLUSION

We aim to share our case to keep cystic fibroses in mind as a differential diagnosis when dealing with hyponatremic seizures in children.

Hyponatremia and its associated factors in children admitted to the pediatric intensive care unit in eastern Ethiopia: a cross-sectional study

BACKGROUND

Hyponatremia is a serious problem that leads to substantial increases morbidity and mortality in critically ill children. The identification of risk factors, implementation of preventive measures, and timely diagnosis and management are crucial to reduce adverse events related to hyponatremia. Despite the higher burden of the problem in Ethiopia, evidence related to the risk factors for hyponatremia among children in Ethiopia is limited; in particular, no study has been identified in eastern Ethiopia. Therefore, we aimed to determine the magnitude of hyponatremia and its associated factors in children admitted to the pediatric intensive care unit at the Hiwot Fana Comprehensive Specialized University Hospital.

METHODS

A facility-based cross-sectional study was conducted using 422 medical records of pediatric patients admitted to the pediatric intensive care unit at Hiwot Fana Comprehensive Specialized University Hospital from January 2019 to December 2022. Medical records were reviewed to collect data. Data were analyzed using a statistical package for social sciences (SPSS) version 26. A binary logistic regression model with an adjusted odds ratio (aOR) and a 95% confidence interval (CI) was used to identify factors associated with the outcome variable. Statistical significance was set at p < 0.05.

RESULTS

The magnitude of hyponatremia was 39.1% (95% CL: 34.4-43.8%). The age of the child (aOR = 2.37;95% CL:1.31-4.31), diagnosis of sepsis (aOR = 2.33; 95% CL:1.41-3.84),   surgical procedures (aOR = 2.39; 95% CL:1.26-4.56), nutritional status (aOR = 2.60; 95% CL:1.51-4.49), and length of hospital stay (aOR = 3.04; 95% CL: 1.73-5.33) were factors significantly associated with hyponatremia.

CONCLUSIONS

Four out of ten children admitted to pediatric intensive care units had hyponatremia. Hyponatremia was significantly associated with the age of the child, malnutrition, sepsis, surgical procedures, and length of hospital stay. To reduce the burden of hyponatremia and associated mortality, attention should be focused on improving the care of malnourished children, and those with sepsis, and the quality of postoperative monitoring services. Moreover, intervention strategies aimed at reducing the burden of hyponatremia should target the identified factors.

Hyponatremia after craniotomy in children: a single-institution review

PURPOSE

Hyponatremia after craniotomy can be associated with increased morbidity. However, the incidence of and factors associated with post-craniotomy hyponatremia in children are not known.

METHODS

We performed a retrospective cohort study of patients aged 0-21 years who underwent craniotomy in 2017-2019 at a single center to determine the incidence of and to identify risk factors for hyponatremia after craniotomy. Indications for craniotomy included tumors (excluding craniopharyngioma), epilepsy, intracranial infection, trauma, craniofacial, suboccipital decompression for the treatment of Chiari malformation, and cerebrovascular disease. Hyponatremia was defined as a serum sodium level ≤ 135 mEq/L any time during the postoperative hospital stay. Statistical significance was defined a priori at p < 0.05.

RESULTS

Postoperative hyponatremia occurred in 61 (25%) of 240 children. On univariate analysis, hyponatremia was associated with younger age (8.5 vs 6.3 years, p = 0.01), use of preoperative anti-epileptic drugs (p = 0.02), need for blood transfusion (p = 0.02), government/private insurance (p = 0.04), and pre-existing hydrocephalus, defined as the requirement for permanent cerebrospinal fluid (CSF) diversion (p = 0.04). On multivariate analysis, only hydrocephalus (OR 2.95, 95% CI 1.03-8.40) remained statistically significant. Hyponatremia most occurred on the first postoperative day, with normonatremia achieved in a median of 14 (IQR 9.8-24.3) h. Hyponatremia was significantly associated with longer length of stay (median 8 vs 3 days, p < 0.01).

CONCLUSION

Hyponatremia was present in 25% of children after craniotomy. Preoperative hydrocephalus as an independent risk factor for hyponatremia after craniotomy.

Case report: Hypoadrenocorticism crisis complicated by non-cardiogenic pulmonary edema in a dog

A 6-year-old castrated male Labradoodle was referred in uncompensated hypovolemic shock, with a 72-h history of lethargy, vomiting and diarrhea that had acutely worsened with subsequent development of profuse hemorrhagic diarrhea in the last 24 h after a visit to the groomer. In most respects this case was classic for a patient with a primary hypoadrenocortical crisis. After initial attempts to address hypovolemia and refractory hypotension, no clinical improvement was seen, and the respiratory rate had increased acutely to 80 bpm with crackles detected on thoracic auscultation and serosanguineous fluid began draining from the nose and mouth. An arterial blood gas sample while breathing room air revealed moderate hypoxemia (PaO2 59.9: RI 95–100 mmHg), an elevated alveolar-arterial (A-a) gradient at 54.7 (RI &lt; 15 mmHg) and a PaO2:FiO2 ratio of 285 mmHg. Thoracic radiographs revealed severe bilateral alveolar lung pattern largely limited to the perihilar and caudodorsal lung fields. The radiographic findings, along with signs of ongoing hypovolemia, the lack of evidence of typical long-standing acquired cardiac disease, and the rapid resolution of the pulmonary edema without the need for diuretics or long-term cardiac medications supported non-cardiogenic pulmonary edema. The proposed cause of the non-cardiogenic pulmonary edema was speculated to be neurogenically mediated. Oxygen supplementation along with mineralocorticoid and glucocorticoid replacement therapy was sufficient for the management of the non-cardiogenic pulmonary edema in this case.

0.45% Versus 0.9% Saline in 5% Dextrose as Maintenance Fluids in Children Admitted With Acute Illness: A Randomized Control Trial

BACKGROUND

The safety of giving intravenous (IV) maintenance fluids according to Holliday and Segar's recommendations of 1957 has recently been questioned after reports of complications caused by iatrogenic hyponatremia in children receiving hypotonic fluids. However, the current practice of choice of maintenance IV fluids for hospitalized children varies worldwide. This study was planned to compare 0.45% and 0.9% saline in 5% dextrose at standard maintenance rates in hospitalized children aged 3 months to 12 years.

OBJECTIVE

Primary objective was to study change in serum sodium level at 24 hours in children receiving total IV fluid maintenance therapy as 0.45% or 0.9% normal saline in 5% dextrose. Secondary objectives of this study were to estimate change in serum sodium levels from the baseline to 48 or 72 hours, if IV fluids were continued, and to find incidence of hyponatremia and hypernatremia after administering these 2 types of maintenance fluids.

METHODS

This study was an open-label, randomized control trial conducted at the Department of Pediatrics of a tertiary care hospital from July 22, 2019, to October 28, 2019. Two hundred children aged 3 months to 12 years admitted in pediatric emergency and requiring IV maintenance fluid were randomized into 2 groups (group A received 0.45% saline in 5% dextrose, group B received 0.9% normal saline in 5% dextrose) with 100 in each group.

RESULTS

Both groups were comparable for baseline characteristics. Fall in mean serum sodium from baseline was more with increasing duration of IV fluids until 24 hours in 0.45% saline group as compared with 0.9% saline group, which was statistically significant (P < 0.001). The incidence of mild and moderate hyponatremia was significantly more in hypotonic group at 12 hours (P < 0.001) and 24 hours (P < 0.001). However, there was no significant difference at 48 hours.

CONCLUSIONS

The fall in serum sodium values was significant, and there was significant risk of hyponatremia with the use of hypotonic fluids at 12 and 24 hours. Hence, the use of isotonic fluids seems to be more appropriate among the hospitalized children.Trial Registration: CTRI/2019/10/021791.

Postoperative dysnatremia in infants after open-heart surgery occurs frequently and is associated with prolonged intensive care length of stay

BACKGROUND

Dysnatremia after surgery for congenital heart disease (CHD) is well known and has been associated with prolonged pediatric intensive care unit length of stay (PICU-LOS). Fluctuations in plasma sodium levels occur perioperatively. The primary aim of the study was to evaluate the occurrence of dysnatremia during the first 48 h after surgery and whether it was associated with PICU-LOS. The secondary aim was to evaluate if the degree of sodium fluctuations was associated with PICU-LOS.

METHODS

A retrospective observational, single-center study including infants undergoing surgery for CHD. The highest and lowest plasma sodium value was registered for the prespecified time periods. PICU-LOS was analyzed in relation to the occurrence of dysnatremia and the degree of plasma sodium fluctuations. The occurrence of dysnatremia was evaluated in relation to surgical procedure and fluid administration.

RESULTS

Two hundred and thirty infants who underwent 249 surgical procedures were included. Dysnatremia developed in more than 60% within 48 h after surgery. Infants with normonatremia had a 40%-50% shorter PICU-LOS among children in RACHS-1 category 3-6, compared with infants developing either hypo- or hyper-/hyponatremia within 48 h after surgery (p = .006). Infants who had a decline of plasma sodium >11 mmol/L had almost double the PICU-LOS compared to those with a decline of <8 mmol/L.

CONCLUSION

Dysnatremias were common after surgery for CHD and associated with prolonged PICU-LOS. The degree of decline in plasma sodium was significantly associated with PICU-LOS. Fluid administration both in terms of volume and components (blood products and crystalloids) as well as diuresis were related to the occurrence of dysnatremias.

A Survey of Hospital Pharmacy Guidelines for the Administration of 3% Sodium Chloride in Children

Three percent sodium chloride (3% NaCl) is the treatment of choice for symptomatic hyponatremia. A barrier to the use of 3% NaCl is the perceived risk of both local infusion reactions and neurologic complications from overcorrection. We examine whether children’s hospital pharmacies have policies or practice guidelines for the administration of 3% NaCl and whether these pharmacies have restrictions on the administration of 3% NaCl in terms of rate, route, volume and setting. An Internet survey was distributed to the pharmacy directors of 43 children’s hospitals participating in the Children’s Hospital Association (CHA) network. The response rate was 65% (28/43). Ninety-three percent (26/28) of pharmacy directors reported a restriction for the administration of 3% NaCl, with 57% restricting its use through a peripheral vein or in a non-intensive care unit setting, 68% restricting the rate of administration and 54% restricting the volume of administration. Seventy-one percent (20/28) reported having written policy or practice guidelines. Only 32% of hospital pharmacies allowed 3% NaCl to be administered through a peripheral IV in a non-intensive care unit setting. The majority of children’s hospital pharmacies have restrictions on the administration of 3% NaCl. These restrictions could prevent the timely administration of 3% NaCl in children with symptomatic hyponatremia.

Severe hospital-acquired hyponatremia in acutely ill children receiving moderately hypotonic fluids

BACKGROUND

Hypotonic fluids have been associated with hospital-acquired hyponatremia. The incidence of life-threatening severe hyponatremia associated with hypotonic fluids has not been evaluated.

METHODS

This was a population-based cohort study of 46,518 acutely ill children 15 years of age or under who visited the pediatric emergency department (ED) at Oulu University Hospital, Finland, between 2007 and 2017. We retrieved all electrolyte measurements from the comprehensive electronic laboratory system and reviewed medical records for all patients with severe hyponatremia.

RESULTS

The overall occurrence of severe hyponatremia (serum sodium < 125 mmol/L) was found in 27 out of 46,518 acutely ill children (0.06%, 95% confidence interval 0.04-0.08%). After admission, severe hyponatremia developed in seven of 6,984 children receiving moderately hypotonic fluid therapy (0.1%, 95% confidence interval 0.04-0.2%), usually within 8 h of admission. All children who developed severe hyponatremia during hospitalization were severely ill.

CONCLUSION

In this register-based cohort study of children presenting to the ED, severe hyponatremia developed in one of 998 acutely ill children receiving moderately hypotonic fluid therapy. A higher resolution version of the Graphical abstract is available as Supplementary information.

Prevalence, prognostic value, pathophysiology, and management of hyponatraemia in children and adolescents with COVID-19

Hyponatraemia is frequently encountered in adults with coronavirus disease 2019 (COVID-19) and is associated with poor prognosis. This review aims to describe for the first time the prevalence, aetiology, prognostic value, pathophysiology, and management of hyponatraemia in children and adolescents with COVID-19, taking into account all relevant studies published in PubMed and Cochrane Library studies until 26th September 2021. Literature search did not detect any studies evaluating the prevalence and prognostic value of sodium disorders in paediatric patients with COVID-19. A broader literature review showed a high prevalence of hyponatraemia in children with bacterial pneumonia, while some studies have reported that hyponatraemia is relatively common in Multisystem Inflammatory Syndrome in Children (MIS-C). In adults with COVID-19, an inverse association between sodium and interleukin-6 levels has been found, indicating that hyponatraemia could be used as a surrogate marker for the risk of cytokine storm and may facilitate the identification of patients who could benefit from immunomodulatory agents. Studies are urgently needed to evaluate the frequency and prognostic impact of electrolyte abnormalities in children with COVID-19. In the meantime, clinicians are urged to consider hyponatraemia in children with COVID-19 as a potential red flag, investigate the cause and administer fluids and other therapies accordingly.

Testing the combined effects of probiotics and prebiotics against neurotoxic effects of propionic acid orally administered to rat pups

The present study investigated the combined effects of mixed probiotic and bee pollen on brain intoxication induced by propionic acid (PPA) in rat pups. Thirty western albino rats were divided into five groups, six animals each: (1) Control group receiving phosphate-buffered saline; (2) Probiotic and bee pollen-treated group being administered at the same dose with 200 mg/kg body weight; (c) PPA-treated group receiving a neurotoxic dose 250 mg/kg body weight of PPA for 3 days; (d) Therapeutic group being administered the neurotoxic dose of PPA followed by probiotic and bee pollen treatment 200 mg/kg body weight; (e) Protective group receiving probiotic and bee pollen mixture treatment followed by neurotoxic dose of PPA. Selected biochemical parameters linked to oxidative stress, energy metabolism, and neurotransmission were investigated in brain homogenates from all the five groups. PPA treatment showed an increase in oxidative stress markers like lipid peroxidation coupled with a significant decrease in glutathione level. Impaired energy metabolism was ascertained via the alteration of creatine kinase (CK) and lactate dehydrogenase (LDH) activities. Dramatic increase of Na+ and K+ concentrations together with a decrease of GABA and IL-6 and an elevation of glutamate levels in PPA-treated rat's pups confirmed the neurotoxicity effect of PPA. Interestingly, the mixed probiotic and bee pollen treatment were effective in restoring the levels of glutamate, GABA, and IL-6 in addition to normalizing the levels of lipid peroxidation and glutathione and the activities of CK and LDH. The present study indicates that mixed probiotic and bee pollen treatment can improve poor detoxification, oxidative stress, and neuroinflammation as mechanisms implicated in the etiology of autism.

Vasopressin-Dependent Disorders: What Is New in Children?

Arginine vasopressin (AVP)-mediated osmoregulatory disorders, such as diabetes insipidus (DI) and syndrome of inappropriate secretion of antidiuretic hormone (SIADH) are common in the differential diagnosis for children with hypo- and hypernatremia and require timely recognition and treatment. DI is caused by a failure to concentrate urine secondary to impaired production of or response to AVP, resulting in hypernatremia. Newer methods of diagnosing DI include measuring copeptin levels; copeptin is AVP's chaperone protein and serves as a surrogate biomarker of AVP secretion. Intraoperative copeptin levels may also help predict the risk for developing DI after neurosurgical procedures. Copeptin levels hold diagnostic promise in other pediatric conditions, too. Recently, expanded genotype and phenotype correlations in inherited DI disorders have been described and may better predict the clinical course in affected children and infants. Similarly, newer formulations of synthetic AVP may improve pediatric DI treatment. In contrast to DI, SIADH, characterized by inappropriate AVP secretion, commonly leads to severe hyponatremia. Contemporary methods aid clinicians in distinguishing SIADH from other hyponatremic conditions, particularly cerebral salt wasting. Further research on the efficacy of therapies for pediatric SIADH is needed, although some adult treatments hold promise for pediatrics. Lastly, expansion of home point-of-care sodium testing may transform management of SIADH and DI in children. In this article, we review recent developments in the understanding of pathophysiology, diagnostic workup, and treatment of better outcomes and quality of life for children with these challenging disorders.

Severe hyponatremia in children: a review of the literature through instructive cases

Hyponatriemia is the most common electrolyte disorder in the paediatric population. Symptoms are related to the time in which hyponatriemia has developed. The acute presentation could be dramatic, with neurological symptoms like headache, seizure, impaired mental status and even coma. It is essential for the physician to be aware of the possible causes of hyponatremia in the child in order to start a prompt treatment.

Risk of Overcorrection in Rapid Intermittent Bolus vs Slow Continuous Infusion Therapies of Hypertonic Saline for Patients With Symptomatic Hyponatremia: The SALSA Randomized Clinical Trial

IMPORTANCE

Few high-quality studies have clarified whether hypertonic saline is best administered as slow continuous infusion (SCI) therapy or rapid intermittent bolus (RIB) therapy for symptomatic severe hyponatremia.

OBJECTIVE

To compare the risk of overcorrection in RIB and SCI with hypertonic saline in patients with symptomatic hyponatremia.

DESIGN, SETTING, AND PARTICIPANTS

This prospective, investigator-initiated, multicenter, open-label, randomized clinical trial enrolled 178 patients older than 18 years with moderately severe to severe hyponatremia and glucose-corrected serum sodium (sNa) levels of 125 mmol/L or less. Recruitment took place from August 24, 2016, until August 21, 2019, across emergency departments and wards of 3 general hospitals in the Republic of Korea.

INTERVENTIONS

Either RIB or SCI of hypertonic saline, 3%, for 24 to 48 hours stratified by the severity of clinical symptoms.

MAIN OUTCOME AND MEASURES

The primary outcome was overcorrection at any given period, defined as increase in the sNa level by greater than 12 or 18 mmol/L within 24 or 48 hours, respectively. Secondary and post hoc outcomes included efficacy and safety of the treatment approaches. The sNa concentrations were measured every 6 hours for 2 days.

RESULTS

The 178 patients (mean [SD] age, 73.1 [12.2] years; 80 (44.9%) male; mean [SD] sNa concentrations, 118.2 [5.0] mmol/L) were randomly assigned to the RIB group (n = 87) or the SCI group (n = 91). Overcorrection occurred in 15 of 87 (17.2%) and 22 of 91 (24.2%) patients in the RIB and SCI groups, respectively (absolute risk difference, -6.9% [95% CI, -18.8% to 4.9%]; P = .26). The RIB group showed lower incidence of relowering treatment than the SCI group (36 of 87 [41.4%] vs 52 of 91 [57.1%] patients, respectively; absolute risk difference, -15.8% [95% CI, -30.3% to -1.3%]; P = .04; number needed to treat, 6.3). Groups did not differ in terms of efficacy in increasing sNa concentrations nor improving symptoms, but RIB, when compared with SCI, showed better efficacy in achieving target correction rate within 1 hour (intention-to-treat analysis: 28 of 87 (32.2%) vs 16 of 91 (17.6%) patients, respectively; absolute risk difference, 14.6% [95% CI, 2%-27.2%]; P = .02; number needed to treat, 6.8; per-protocol analysis: 21 of 72 (29.2%) vs 12 of 73 (16.4%) patients, respectively; absolute risk difference, 12.7% [95% CI, -0.8% to 26.2%]; P = .07). The statistical significance of the intention-to-treat and per-protocol analyses were similar for all outcomes except for achieving the target correction rate within 1 hour.

CONCLUSIONS AND RELEVANCE

This randomized clinical trial found that both RIB and SIC therapies of hypertonic saline for treating hyponatremia were effective and safe, with no difference in the overcorrection risk. However, RIB had a lower incidence of therapeutic relowering treatment and tended to have a better efficacy in achieving sNa within 1 hour than SCI. RIB could be suggested as the preferred treatment of symptomatic hyponatremia, which is consistent with the current consensus guidelines.

TRIAL REGISTRATION

ClinicalTrials.org Identifier: NCT02887469.

[Risk factors for the development of early hyponatraemia in the premature infant. A review of the practice of giving sodium in the first days of life]

INTRODUCTION

A retrospective study was conducted in the Neonatal Intensive Care Unit of a tertiary hospital to determine the incidence of early hyponatraemia (first 48hours of life) in preterm infants. Risk and protection factors in this condition were also examined as a starting point for a change in the medical action when prescribing intravenous fluids.

MATERIAL AND METHODS

The study included a sample of 256 premature babies (gestational age: 23⁵-36⁶) admitted to the Neonatal Intensive Care Unit of a tertiary hospital between January 2016 and June 2018. The number of patients receiving intravenous sodium in different intervals during the first 48hours of life was determined, as well as the number of those with hyponatraemia of any type (<135mmol / l), and moderate-severe (<130mmol / l). An analysis was made of the relationship between early hyponatraemia and weight / gestational age, antenatal steroids exposure, respiratory pathology, early sepsis, and perinatal asphyxia.

RESULTS

Hyponatraemia occurred in 81 patients, 31.64% of the total (up to 50% in<30 weeks of gestational age), and was moderate-severe (<130mmol / l) in 17.3% of the cases. The period of time with the most cases of hyponatraemia was in the first 12hours of life (22.64%). Weight (P=.034), gestational age (P<.001) and respiratory disease (P<.001) were found to be risk factors and, in a multivariate analysis, the latter was independently related to early hyponatremia (P<.01, OR=5.24, 95% CI: 2.79-9.84). Antenatal betamethasone exposure did not show to be a protection factor.

CONCLUSION

According to the results of this study, it is considered an advantage to provide sodium in the intravenous fluids prescribed during the first days of life, particularly in preterm infants of lower gestational age and with respiratory disease involvement.

Hyponatraemia in a Lao paediatric intensive care unit: Prevalence, associations and intravenous fluid use

AIM

Hyponatraemia is a common and potentially deadly complication affecting hospitalised children world-wide. Hypotonic intravenous fluids can be a significant exacerbating factor. Exclusive use of isotonic fluids, coupled with rigorous blood monitoring, has proven effective in reducing hyponatraemia in developed settings. In developing countries, where hyponatraemia is often more common and severe, different factors may contribute to its incidence and detection. We aimed to determine the prevalence and disease associations of hyponatraemia and describe the intravenous maintenance fluid prescribing practices in a Lao paediatric intensive care unit.

METHODS

We conducted a cross-sectional study of 164 children aged 1 month to 15 years admitted to intensive care at a tertiary centre in Lao People's Democratic Republic (PDR) and recorded their serum sodium and clinical data at admission and on two subsequent days.

RESULTS

Hyponatraemia was detected in 41% (67/164, confidence interval 34-48%) of children, the majority of which was mild (34%, 56/164) and present at admission (35%, 55/158). Hyponatraemia was more common in malnourished children (odds ratio (OR) 2.3, P = 0.012) and females (OR 1.9, P = 0.045). Hyponatraemia correlated with death or expected death after discharge (OR 2.2, P = 0.015); 88% received maintenance intravenous fluids, with 67% of those receiving a hypotonic solution. Electrolyte testing was only performed in 20% (9/46) of patients outside the study protocol.

CONCLUSIONS

Hyponatraemia is highly prevalent in critically ill children in Lao PDR, as is the continued use of hypotonic intravenous fluids. With financial and practical barriers to safely detecting and monitoring electrolyte disorders in this setting, this local audit can help promote testing and has already encouraged changes to fluid prescribing.

Misconceptions and Barriers to the Use of Hypertonic Saline to Treat Hyponatremic Encephalopathy

Hyponatremic encephalopathy is a potentially life-threatening condition with a high associated morbidity and mortality. It can be difficult to diagnose as the presenting symptoms can be non-specific and do not always correlate with the degree of hyponatremia. It can rapidly progress leading to death from transtentorial herniation. Hypertonic saline is the recommended treatment for hyponatremic encephalopathy, whether acute or chronic, yet it is infrequently used. We believe that the main barriers to its use is the perception that hypertonic saline is associated with a significant risk for cerebral demyelination, that it can't be administered through a peripheral IV and that it requires monitoring in the ICU. Two illustrative cases are presented followed by a discussion of how intermittent bolus's of 100−150 ml of 3% NaCl in rapid succession to acutely increase the plasma sodium by 4−6 mEq/L is a safe and effective way to treat hyponatremic encephalopathy, that can be administered through a peripheral IV in a non-ICU setting.

Syndrome of Inappropriate Antidiuresis

The syndrome of inappropriate antidiuresis (SIAD) is a common cause of hyponatremia in hospitalized children. SIAD refers to euvolemic hyponatremia due to nonphysiologic stimuli for arginine vasopressin production in the absence of renal or endocrine dysfunction. SIAD can be broadly classified as a result of tumors, pulmonary or central nervous system disorders, medications, or other causes such as infection, inflammation, and the postoperative state. The presence of hypouricemia with an elevated fractional excretion of urate can aid in the diagnosis. Treatment options include fluid restriction, intravenous saline solutions, oral sodium supplements, loop diuretics, oral urea, and vasopressin receptor antagonists (vaptans).

A 17-Year-Old Boy With High-Functioning Autism, Gastrointestinal Illness, and Seizures

A healthy 17-year-old boy with a high-functioning pervasive developmental disorder presented to the emergency department after having a 4-minute episode of seizure-like activity in the setting of presumed viral gastroenteritis. Within an hour of emergency department arrival, he developed a forehead-sparing facial droop, right-sided ptosis, and expressive aphasia, prompting stroke team assessment and urgent neuroimaging. Laboratory results later revealed a serum sodium of 119 mmol/L. Neurologic deficits self-resolved, and a full physical examination revealed diffuse abdominal tenderness in the lower abdomen with rebound tenderness in the right-lower quadrant. The patient was admitted to the PICU for electrolyte management and monitoring. A computed tomography (CT) scan of the abdomen obtained the following morning revealed the patient's final diagnosis.

Hyponatremia in children with respiratory infections: a cross-sectional analysis of a cohort of 3938 patients

Hyponatremia can be a life-threatening illness among hospitalized children. The aims of this study were to evaluate the incidence and risk factors of hyponatremia in 3938 children who were admitted to the Cheil General Hospital and Women’s Health Care Center with respiratory infections. Clinical data were collected, and multiplex RT-PCR analyses were done for various microorganisms. Hyponatremia was observed in 531 (13.5%) patients. The incidence of hyponatremia differed according to the respiratory tract infection (P < 0.0001) and microorganism (P = 0.001). In children with hyponatremia, the age at admission was significantly older (P < 0.0001), male gender was more frequent (P = 0.019), CRP was higher (P < 0.0001), and coinfection with multiple organisms was more common (P = 0.001) than in children without hyponatremia. In multivariate analyses, an older age at admission (P = 0.006), male gender (P = 0.004), and increased CRP (P < 0.0001) were independent risk factors. Sodium levels correlated negatively with WBC (P = 0.037), CRP (P < 0.0001), and number of hospital days (P = 0.020). The AUC values of age (0.586, P < 0.0001), CRP (0.599, P < 0.0001), and blood urea nitrogen (0.559, P < 0.0001) were all significant predictors of hyponatremia. This study is the first to show that the incidence of hyponatremia differs according to infecting microorganism and radiological findings.

Full Volume Isotonic (0.9%) vs. Two-Thirds Volume Hypotonic (0.18%) Intravenous Maintenance Fluids in Preventing Hyponatremia in Children Admitted to Pediatric Intensive Care Unit-A Randomized Controlled Study

BACKGROUND

We aimed to compare the effect of two different intravenous fluid regimes on the incidence of hyponatremia in children.

METHODS

Children 1 month to 18 years of age, admitted to pediatric intensive care unit (PICU) of a tertiary care medical college hospital were randomized to receive either isotonic fluid (0.9% saline in 5% dextrose) at the standard maintenance rate or hypotonic fluid (0.18% saline in 5% dextrose) at two-thirds of the standard maintenance rate.

RESULTS

A total of 240 children were randomized (120 isotonic, 120 hypotonic). In all, 16.7% children in hypotonic group developed hyponatremia compared with 7.5% in isotonic group (p = 0.029). Duration of PICU stay was significantly more in Hypotonic group.

CONCLUSION

We conclude that use of 0.9% saline in 5% dextrose as maintenance fluid helps in reducing the incidence of hospital-acquired hyponatremia and duration of intensive care unit stay among children admitted to PICU.

Hyponatremia in children with acute respiratory infections: A reappraisal

Hyponatremia (<135 mmol/L), typically associated with an elevated anti-diuretic hormone level, is common among children admitted with bronchiolitis, pneumonia, or pulmonary exacerbation of cystic fibrosis. The main consequences of acute hyponatremia include cerebral edema and Ayus-Arieff pulmonary edema. A widespread belief is that, in children with pneumonia or bronchiolitis, hyponatremia results from inappropriate anti-diuresis. By contrast, the pathogenic role of extracellular fluid volume depletion or decreased effective circulating blood volume is underscored. Considering the prevalence of hyponatremia, sodium determination is advised on admission in children diagnosed with bronchiolitis, pneumonia, or pulmonary exacerbation of cystic fibrosis. There is no necessity to do anything beyond reassessing the appropriateness of fluid therapy in cases with mild (130-134 mmol/L) hyponatremia. In children with sodium <130 mmol/L, the underlying etiology is sometimes evident from history and physical findings. Given that clinical assessment of fluid volume status is difficult in hyponatremia, further laboratory evaluation is often required in these patients. An increase in sodium level ≤6 mmol/L per day is currently considered the therapeutic goal in all cases. Emergency correction with a 2 mL/kg body weight bolus of 3.0% saline over 10-15 min intravenously is advised in cases with severe symptoms due to hyponatremia and in cases with symptoms, even if mild, due to a rapid-onset (<48 h) of hyponatremia (two additional doses are administered if the patient's condition does not improve).

Risk factors and outcome of Shigella encephalopathy in Bangladeshi children

BACKGROUND

Although, Shigella encephalopathy, a serious extra-intestinal complication of shigellosis, significantly increases the risks of death, data are very limited on predicting factors particularly related to electrolyte profiles in children below five years of age with Shigella encephalopathy. Our objective was to determine the clinical as well as laboratory predicting factors and outcome of children with Shigella encephalopathy.

METHODOLOGY/PRINCIPAL FINDINGS

In this unmatched case-control design, children aged 2-59 months having a positive stool culture for Shigella and who had their serum electrolytes been done from July 2012 to June 2015 were studied. Children with Shigella encephalopathy, defined as having abnormal mentation, constituted the cases, and those without encephalopathy constituted the controls. During the study period, we identified a total of 541 children less than five years of age, who had Shigella in their stool culture. Only 139 children fulfilled the study criteria and among them 69 were cases and 70 were controls. The cases more often had fatal outcome compared to the controls (7% vs. 0%, P = 0.02). In logistic regression analysis, the cases were independently associated with shorter duration (1.2 ± 0.4 days) of diarrhea prior to admission, dehydrating diarrhea, sepsis and hyponatremia (p<0.05 for all). Among 139 Shigella isolates, S. flexneri (88/139, 63%) and S. sonnei(34/139, 24%) were the dominant species. S. dysenteriae was not isolated throughout the study period. S.sonnei was more frequently isolated from the cases (24/69, 35%) than the controls (10/70, 14%), whereas the isolation of S. flexneri was comparable between the groups (40/69, 58% vs 48/70, 69%). A total of 94 (67.6%) isolates were resistant to trimethoprim-sulphamethoxazole, 84 (60.4%) to ciprofloxacin, 66/138 (48%) to ampicillin, 5 (3.5%) to ceftriaxone, 17 (12.2%) to mecillinum and 35 (25%) to azithromycin.

CONCLUSIONS/SIGNIFICANCE

The case-fatality-rate was significantly higher among the children with Shigella encephalopathy compared to those without encephalopathy. Early identification and aggressive management of simple risk factors for Shigella encephalopathy may help to reduce morbidity and deaths in such children especially in resource-limited settings.

Simplifying study of fever's dramatic relief of autistic behavior

Dramatic relief of autistic behavior by infectious fever continues to tantalize parents and practitioners, yet researchers still hesitate to study its physiology/biochemistry, fearing stress and heat of brain imaging, contagion, and fever's complexity. Yet what could be more revealing than a common event that virtually 'normalizes' autistic behavior for a time? This paper proposes study of three simplified scenarios: (1) improvements appearing hours before fever, (2) return of autistic behavior soon after fever, (3) improvements persisting long after fever. Each scenario limits some risk - and some explanation - inviting triangulation of decisive factor(s) in relief and recurrence. Return of autistic behavior after fever may be most revealing. The complex mechanisms that generated fever have all abated; simpler cooling mechanisms prevail - how many plausible explanations can there be? The decisive factor in fever's benefit is concluded to be water drawn/carried from brain myelin and astrocytes by osmolytes glutamine and taurine released from muscles and brain; the decisive factor in return of autistic behavior after fever is return of water.

Efficacy and safety of rapid intermittent correction compared with slow continuous correction with hypertonic saline in patients with moderately severe or severe symptomatic hyponatremia: study protocol for a randomized controlled trial (SALSA trial)

Background

Hyponatremia is the most common electrolyte imbalance encountered in clinical practice, associated with increased mortality and length of hospital stay. However, no high-quality evidence regarding whether hypertonic saline is best administered as a continuous infusion or a bolus injection has been found to date. Therefore, in the current study, we will evaluate the efficacy and safety of rapid intermittent correction compared with slow continuous correction with hypertonic saline in patients with moderately severe or severe symptomatic hyponatremia.

Methods/design

This is a prospective, investigator-initiated, multicenter, open-label, randomized controlled study with two experimental therapy groups. A total of 178 patients with severe symptomatic hyponatremia will be enrolled and randomly assigned to receive either rapid intermittent bolus or slow continuous infusion management with hypertonic saline. The primary outcome is the incidence of overcorrection at any given period over 2 days. The secondary outcomes will include the efficacy and safety of two other approaches to the treatment of hyponatremia with 3% hypertonic saline.

Discussion

This is the first clinical trial to investigate the efficacy and safety of rapid intermittent correction compared with slow continuous correction with hypertonic saline in patients with moderately severe or severe hyponatremia.

Trial registration

ClinicalTrials.gov, identifier number: NCT02887469. Registered on 1 August 2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-1865-z) contains supplementary material, which is available to authorized users.

Pathophysiology of Hyponatremia in Children

Hyponatremia is a common electrolyte disorder in children. It is generally defined as plasma sodium of less than 135 mmol/l. Sodium homeostasis is essential for maintaining intravascular volume and is tightly linked to water balance. Plasma water volume is regulated mainly by the secretion of an antidiuretic hormone (ADH) and by the thirst mechanism. ADH is synthesized in the hypothalamus and stored in the posterior hypophysis. It binds to V2 receptors in the distal nephron and induces translocation of aquaporin water channels in the plasma membrane to retain water. There are two main types of receptors involved in the control of the body water balance-osmoreceptors and baroreceptors. Osmoreceptors reside in hypothalamus and respond to changes of extracellular fluid (ECF) osmolality. Baroreceptors are mechanoreceptors that sense blood pressure in the vessel wall. Response reflexes from baroreceptors influence sympathetic outflow, vessel tonus, and cardiac output. An increase of 1% of plasma osmolality may cause an increase in ADH levels, while the threshold of volume receptors for ADH secretion is higher. However, significant hypotension is a more potent stimulus for ADH secretion than increased osmolality. The main cause of pediatric hyponatremia is an abundance of free water. This may occur in hypovolemic children with low ECF volume, normovolemic patients with inappropriately increased ADH secretion, and also in hypervolemic individuals with decreased effective circulating volume and appropriately increased ADH levels. Proper understanding of the pathophysiology of hyponatremic states is essential for establishing the correct diagnosis and appropriate therapy.

Incidence, Severity, and Association With Adverse Outcome of Hyponatremia in Children Hospitalized With Heart Failure

Hyponatremia is a common finding in adults hospitalized with heart failure (HF) and is associated with longer hospital stays and increased mortality. The significance of hyponatremia in children with HF is not known. We sought to determine the incidence of hyponatremia and association with clinical outcome in children hospitalized with HF. Admission and inpatient serum sodium concentrations were analyzed in 141 consecutive children hospitalized with acute decompensated HF. Inclusion criteria include patients (age, birth to 21 years) with biventricular hearts who were hospitalized for HF from January 2007 to December 2012. The primary composite end point was death, cardiac transplantation, or the use of mechanical circulatory support (MCS) during hospitalization. Data for 141 patients were included in the analysis. The cohort included 48 patients (34%) with preexisting HF. Mean serum sodium at admission was 136 ± 4 mmol/L (range 124 to 150 mmol/L). Hyponatremia (serum sodium <135 mmol/L) was present in 45 patients (32%) at admission. Seventy-one patients (75%) with normal serum sodium concentrations at admission subsequently developed acquired hyponatremia during their hospitalization. Hyponatremia persisted at discharge in 17 of 66 patients (26%). Fifty-eight patients (41%) reached the composite end point during hospitalization (death, n = 15; cardiac transplantation, n = 27; MCS, n = 46). Hyponatremia at admission was independently associated with death, cardiac transplantation, or the use of MCS during hospitalization (odds ratio 3.1, p = 0.02). In conclusion, hyponatremia occurs commonly in children hospitalized with acute decompensated HF and is associated with increased risk of in-hospital mortality, cardiac transplantation, and need for MCS.

Analysis of Risk Factors for Hyponatremia During or Following Chemotherapy in Children With Cancer: A Hospital-based, Retrospective Cohort Study

Hyponatremia is the most common electrolyte abnormality in hospitalized patients. The objective of this study was to identify risk factors for hyponatremia during chemotherapy in children. A total of 111 consecutive pediatric patients (age, 0 to 18 y) with hematological malignancy (n=87) or solid tumor (n=24) who received chemotherapy in our hospital between 2010 and 2014 were enrolled. The number of chemotherapy cycles reviewed was 472, with a median of 3 (range, 1 to 8) per patient. Hyponatremia was defined as a serum sodium level of <135 mmol/L. Hyponatremia was observed in 80 of 111 (72%) patients, and 138 of 472 (29%) cycles. Neurological sequelae were seen in 2 of 111 (2%) patients, and 2 of 472 (0.4%) cycles. Multivariate logistic regression identified age 10 to 18 years (odds ratio [OR]=3.24, 95% confidence interval [CI], 2.07-5.07), total parenteral nutrition (OR=8.15, 95% CI, 2.17-30.5), first or second chemotherapy cycle (OR=1.74, 95% CI, 1.12-2.70) as independent risk factors for hyponatremia. Clinical conditions of patients and chemotherapeutic agents may have a profound impact on the development of hyponatremia. Patients with these factors should be managed carefully to prevent severe symptoms and sequelae caused by hyponatremia.

A prospective trial comparing isotonic with hypotonic maintenance fluids for prevention of hospital-acquired hyponatraemia

BACKGROUND

Recent literature suggests that hypotonic fluids increase the risk of hospital-acquired hyponatraemia; despite this, hypotonic fluids are widely used.

OBJECTIVES

To compare the change in serum sodium following the use of hypotonic (0.3% saline, 0.45% saline) or isotonic (0.9% saline) intravenous (IV) maintenance solutions in hospitalised children.

STUDY DESIGN

This was a randomised controlled trial. Children aged 3 months to 15 years with medical or surgical disorders were randomised to receive one of three maintenance IV fluids: two hypotonic solutions (3.3% dextrose in 0.3% saline or 5% dextrose in 0.45% saline) and one isotonic solution (5% dextrose in 0.9% saline). The primary outcome was serum sodium levels at 8 hours. Secondary outcomes included the incidence of hospital-acquired hyponatraemia, adverse events attributable to IV solutions and length of hospital stay.

RESULTS

151 children were assigned randomly to receive 0.3% saline (n = 49), 0.45% saline (n = 50) or 0.9% saline (n = 52). Baseline characteristics were similar for the three groups. At 8 hours, mean (SD) serum sodium was lower in the hypotonic solutions groups [0.3% saline 134.65 (1.9) mmol/L, 0.45% saline 134.90 (2.3) mmol/L than 0.9% saline 137.98 (2.8) mmol/L] (P < 0.0001). The incidence of hospital-acquired hyponatraemia was higher in the hypotonic groups [0.3% saline 10/49 (20.4%), 0.45% saline 11/50 (22%) than 0.9% saline 1/52 (1.9%), P = 0.006). There were no differences in other adverse effects or length of hospital stay between the groups.

CONCLUSION

Hypotonic IV solutions increase the incidence of hospital-acquired hyponatraemia. Isotonic solutions are a safer alternative.

Etiology of postoperative hyponatremia following pediatric intracranial tumor surgery

OBJECT Cerebral salt wasting (CSW) and the syndrome of inappropriate antidiuretic hormone secretion (SIADH) cause postoperative hyponatremia in neurosurgery patients, can be difficult to distinguish clinically, and are associated with increased morbidity. The authors aimed to determine risk factors associated with CSW and SIADH among children undergoing surgery for intracranial tumors. METHODS This retrospective cohort study included children 0-19 years of age who underwent a first intracranial tumor surgery with postoperative hyponatremia (sodium ≤ 130 mEq/L). CSW was differentiated from SIADH by urine output and fluid balance, exclusive of other causes of hyponatremia. The CSW and SIADH groups were compared with basic bivariate analysis and recursive partitioning. RESULTS Of 39 hyponatremic patients, 17 (44%) had CSW and 10 (26%) had SIADH. Patients with CSW had significantly greater natriuresis compared with those with SIADH (median urine sodium 211 vs 28 mEq/L, p = 0.01). Age ≤ 7 years and female sex were significant risk factors for CSW (p = 0.03 and 0.04, respectively). Both patient groups had hyponatremia onset within the first postoperative week. Children with CSW had trends toward increased sodium variability and symptomatic hyponatremia compared with those with SIADH. Most received treatment, but inappropriate treatment was noted to worsen hyponatremia. CONCLUSIONS The authors found that CSW was more common following intracranial tumor surgery and was associated with younger age and female sex. Careful assessment of fluid balance and urine output can separate patients with CSW from those who have SIADH, and high urine sodium concentrations (> 100 mEq/L) support a CSW diagnosis. Patients with CSW and SIADH had similar clinical courses, but responded to different interventions, making appropriate diagnosis and treatment imperative to prevent morbidity.

Low sodium status in cystic fibrosis-as assessed by calculating fractional Na(+) excretion-is associated with decreased growth parameters

BACKGROUND

In CF infants, normonatremic Na(+) depletion (NNaD), identified by fractional Na(+) excretion (FENa) values <0.5%, was recently linked to impaired growth. Our paper investigates the relationship between FENa and growth in CF children >2years.

METHODS

FENa values were calculated in 35 CF and 24 control children, and tested for correlations with z-scores for weight, height and BMI.

RESULTS

All CF children and controls had normal plasma Na(+) concentrations. A total of 25 of 35 (71.4%) CF patients had decreased FENa values <0.5% (group I). FENa results of 10 CF patients (group II) and 23/24 controls (group III) were normal. In Na(+)-depleted CF children, compared to normal controls, mean z-scores for weight (-0.18±0.87 vs +1.03±0.57, p<0.001), height (-0.06±0.89 vs +0.53±0.72, p=0.009) and BMI (-0.22±0.87 vs +1.00±1.06, p<0.001) were significantly reduced. Also, we found positive correlations between FENa values and z-scores for weight (r=0.521), height (r=0.292) and BMI (r=0.468), respectively.

CONCLUSION

NNaD may contribute to poor growth in CF.

Hyponatremia, hypo-osmolality, and seizures in children early post-kidney transplant

Post-transplant seizures are uncommon in young kidney transplant recipients but can be harbingers of devastating outcomes such as cerebral edema and death. We reviewed all transplants performed at our institution from January 2013 to January 2014 and compared three patients who seized within 24 h post-transplant (cases) with the remaining 33 transplant recipients (controls). Records were reviewed for hyponatremia, hypocalcemia, hypomagnesemia, BUN clearance, osmolality shifts, and blood pressure control in the first 24 h post-transplant. All cases had more pronounced (p < 0.001) shifts in serum sodium and calculated serum osmolality, with their sodium decreasing by >15 mmol/L to nadir values of 124, 131, and 131 mmol/L, respectively. There were no differences in serum calcium corrected for hypoalbuminemia, serum magnesium, urine output, or blood pressure control between the groups. Our study suggests that mild hyponatremia and an acute decrease in serum osmolality are risk factors for potentially severe postoperative neurologic complications following kidney transplantation. Thus, peri-transplant management should be optimized to anticipate and prevent these abnormalities.