Treatment of acute hypernatremia with hemodialysis

Central and nephrogenic diabetes insipidus: updates on diagnosis and management

Diabetes insipidus (DI) is a rare endocrine disease involving antidiuretic hormone (ADH), encompassing both central and nephrogenic causes. Inability to respond to or produce ADH leads to inability of the kidneys to reabsorb water, resulting in hypotonic polyuria and, if lack of hydration, hypernatremia. DI cannot be cured and is an unfamiliar disease process to many clinicians. This diagnosis must be distinguished from primary polydipsia and other causes of hypotonic polyuria. The main branchpoints in pathophysiology depend on the level of ADH pathology: the brain or the kidneys. Prompt diagnosis and treatment are critical as DI can cause substantial morbidity and mortality. The gold standard for diagnosis is a water deprivation test followed by desmopressin administration. There is promising research regarding a new surrogate marker of ADH called copeptin, which may simplify and improve the accuracy in diagnosing DI in the future. Patients with DI require adequate access to water, and there are nuances on treatment approaches depending on whether a patient is diagnosed with central or nephrogenic DI. This article describes a stepwise approach to recognition, diagnosis, and treatment of DI.

Serum osmolality and hyperosmolar states

Serum osmolality is the sum of the osmolalities of every single dissolved particle in the blood such as sodium and associated anions, potassium, glucose, and urea. Under normal conditions, serum sodium concentration is the major determinant of serum osmolality. Effective blood osmolality, so-called blood tonicity, is created by the endogenous (e.g., sodium and glucose) and exogenous (e.g., mannitol) solutes that are capable of creating an osmotic gradient across the membranes. In case of change in effective blood osmolality, water shifts from the compartment with low osmolality into the compartment with high osmolarity in order to restore serum osmolality. The difference between measured osmolality and calculated osmolarity forms the osmolal gap. An increase in serum osmolal gap can stem from the presence of solutes that are not included in the osmolarity calculation, such as hypertonic treatments or toxic alcoholic ingestions. In clinical practice, determination of serum osmolality and osmolal gap is important in the diagnosis of disorders related to sodium, glucose and water balance, kidney diseases, and small molecule poisonings. As blood hypertonicity exerts its main effects on the brain cells, neurologic symptoms varying from mild neurologic signs and symptoms to life-threatening outcomes such as convulsions or even death may occur. Therefore, hypertonic states should be promptly diagnosed and cautiously managed. In this review, the causes and treatment strategies of hyperosmolar conditions including hypernatremia, diabetic ketoacidosis, hyperglycemic hyperosmolar syndrome, hypertonic treatments, or intoxications are discussed in detail to increase awareness of this important topic with significant clinical consequences.

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.

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.

Prevalence and Prognostic Impact of Hypernatremia in Sepsis and Septic Shock Patients in the Intensive Care Unit: A Single Centre Experience

Introduction

Hypernatremia is a commonly associated electrolyte disturbance in sepsis and septic shock patients in the ICU. The objective of this study was to identify the prognostic value of hypernatremia in sepsis and septic shock

Material and Methods

A prospective study conducted on sepsis and septic shock patients diagnosed prior to admission in the ICU in King Hamad University Hospital, Bahrain from January 1st 2017 to February 28th 2019. Data including age, sex, comorbidities, source of sepsis, sodium levels on days one, three, and seven. Data was correlated with the outcome (survival/death and the length of ICU stay).

Results

Patients included were 168, 110 survived, and 58 died. Hypernatraemia at day seven was associated with significantly higher mortality (P= 0.03). Hypernatraemia at Day1was associated with a significantly prolonged stay in the ICU (p= 0.039).Multivariate analysis to identify the independent predictors of mortality revealed that immunosuppression and hypernatraemia at Day7 proved to be independent predictors of mortality (P= 0.026 and 0.039 respectively).

Conclusion

Hypernatremia can be an independent predictor of poor outcome in septic and septic shock patients in the ICU.

Continuous veno-venous hemofiltration in the treatment of severely burned patients with acute hypernatremia: A retrospective study of 13 cases

OBJECTIVES

This study aimed to evaluate the clinical effects of continuous veno-venous hemofiltration in the treatment of severely burned patients with acute hypernatremia.

METHODS

A total of 13 severely burned patients with acute hypernatremia admitted to Xijing Hospital were included in this study. All patients received continuous veno-venous hemofiltration treatment in addition to conventional treatment. The original sodium level in the replacement fluid was set to be lower than the serum sodium level by 8 mmol/L and subsequently undergoes a reduction rate of 2.16 ± 0.18 mmol/L every 4 h. Patients' clinical features, serum laboratory tests, hemodynamic variables, changes in sodium levels in serum, and replacement fluid during continuous veno-venous hemofiltration treatment were monitored.

RESULTS

Patients had an average total burn surface area of 66.69% ± 20.28%. Two patients died of systematic Pseudomonas aeruginosa infections, and 11 patients survived. After continuous veno-venous hemofiltration treatment, patients showed a significant reduction in the serum sodium level (168.91 ± 4.88 mmol/L vs 144.62 ± 2.98 mmol/L, p < 0.01). Likewise, the serum levels of urea and creatinine decreased from 24.8 ± 6.5 mmol/L to 14.9 ± 8.3 mmol/L and from 278.6 ± 155.3 μmol/L to 152.6 ± 29.7 μmol/L, respectively (p < 0.05). The patients also displayed improvements in the Acute Physiology and Chronic Health Evaluation II and Glasgow scores (p < 0.05) and showed a significant reduction in hemoglobin and serum albumin levels (p < 0.05), but no obvious change in levels of platelets, alanine aminotransferase, and aspartate aminotransferase (p > 0.05).

CONCLUSION

Our results indicate that continuous veno-venous hemofiltration with gradient sodium replacement fluid is effective in treating hypernatremia in severely burned patients with the controllable sodium reduction rate and satisfactory clinical outcomes.

Hypertonicity: Clinical entities, manifestations and treatment

Hypertonicity causes severe clinical manifestations and is associated with mortality and severe short-term and long-term neurological sequelae. The main clinical syndromes of hypertonicity are hypernatremia and hyperglycemia. Hypernatremia results from relative excess of body sodium over body water. Loss of water in excess of intake, gain of sodium salts in excess of losses or a combination of the two are the main mechanisms of hypernatremia. Hypernatremia can be hypervolemic, euvolemic or hypovolemic. The management of hypernatremia addresses both a quantitative replacement of water and, if present, sodium deficit, and correction of the underlying pathophysiologic process that led to hypernatremia. Hypertonicity in hyperglycemia has two components, solute gain secondary to glucose accumulation in the extracellular compartment and water loss through hyperglycemic osmotic diuresis in excess of the losses of sodium and potassium. Differentiating between these two components of hypertonicity has major therapeutic implications because the first component will be reversed simply by normalization of serum glucose concentration while the second component will require hypotonic fluid replacement. An estimate of the magnitude of the relative water deficit secondary to osmotic diuresis is obtained by the corrected sodium concentration, which represents a calculated value of the serum sodium concentration that would result from reduction of the serum glucose concentration to a normal level.

Risk Factors and Outcomes in Patients With Hypernatremia and Sepsis

BACKGROUND

Hypernatremia is an uncommon but important electrolyte abnormality in intensive care unit patients. Sepsis is one of the most common causes of intensive care unit admission, but few studies about the role of hypernatremia in sepsis has been published yet. In this study, we aimed to explore the risk factors for developing hypernatremia in patients with sepsis, and the prognosis of patients with sepsis with or without hypernatremia was also assessed.

MATERIALS AND METHODS

In this retrospective cohort study of 51 septic intensive care unit patients at a single center, we examined the risk factors for the development of hypernatremia and the association of hypernatremia with clinical outcomes using univariate and multivariable analyses. Clinical outcomes such as mortality and hospital duration of patients with or without hypernatremia were also compared.

RESULTS

Acute Physiology and Chronic Health Evaluation II score (odds ratio = 1.15; 95% CI: 1.022-1.294) was found to be the only independent risk factor for hypernatremia in patients with sepsis. Moreover, patients developing hypernatremia during hospitalization showed significantly higher morbidity and mortality.

CONCLUSIONS

Acute Physiology and Chronic Health Evaluation II score may be an independent risk factor for hypernatremia in patients with sepsis. Moreover, hypernatremia is strongly associated with worse outcome in sepsis.

Continuous veno-venous hemodialysis and filtration for extensive burn with severe hypernatremia

Case

A 51-year-old man presented with severe burns, with a burn index of 33.5. Relaxation incisions were made in the trunk and right arm. Ringer's solution (12,000 mL) was used as initial fluid therapy for the first 24 h. The patient's serum Na level gradually increased to 170 mEq/L; infusion was carried out to correct the hypernatremia. Continuous veno-venous hemodialysis and filtration succeeded in maintaining the serum Na level at approximately 145 mEq/L.

Outcome

After the initiation of continuous veno-venous hemodialysis and filtration, the skin graft survival rate improved markedly with the normalization of the Na level, and the patient recovered smoothly. He was discharged on foot.

Conclusion

Hypernatremia, frequently observed in patients with extensive burns, is considered to be markedly disadvantageous for the survival of skin grafts. Continuous veno-venous hemodialysis and filtration may be one of the options for the treatment of refractory hypernatremia in severe burns.

Hypernatremia: correction rate and hemodialysis

Severe hypernatremia is defined as serum sodium levels above 152 mEq/L, with a mortality rate ≥60%. 85-year-old gentleman was brought to the emergency room with altered level of consciousness after refusing to eat for a week at a skilled nursing facility. On admission patient was nonverbal with stable vital signs and was responsive only to painful stimuli. Laboratory evaluation was significant for serum sodium of 188 mmol/L and water deficit of 12.0 L. Patient was admitted to medicine intensive care unit and after inadequate response to suboptimal fluid repletion, hemodialysis was used to correct hypernatremia. Within the first fourteen hours, sodium concentration only changed 1 mEq/L with a fluid repletion; however, the concentration dropped greater than 20 mEq/L within two hours during hemodialysis. Despite such a drastic drop in sodium concentration, patient did not develop any neurological sequela and was at baseline mental status at the time of discharge.

Survival of acute hypernatremia due to massive soy sauce ingestion

BACKGROUND

Intentional massive sodium chloride ingestions are rare occurrences and are often fatal.

OBJECTIVES

There are a variety of treatment recommendations for hypernatremia, ranging from dialysis to varying rates of correction. We report a case of acute severe hypernatremia corrected with rapid free-water infusions that, to our knowledge, has not been previously reported.

CASE REPORT

A 19-year-old man presented to the Emergency Department in a comatose state with seizure-like activity 2 hours after ingesting a quart of soy sauce. He was administered 6 L of free water over 30 min and survived neurologically intact without clinical sequelae. Corrected for hyperglycemia, the patient's peak serum sodium was 196 mmol/L, which, to our knowledge, is the highest documented level in an adult patient to survive an acute sodium ingestion without neurologic deficits.

CONCLUSION

Emergency physicians should consider rapidly lowering serum sodium with hypotonic intravenous fluids as a potential management strategy for acute severe hypernatremia secondary to massive salt ingestion.

Pediatric renal replacement therapy in the intensive care unit

Renal replacement therapy (RRT) is used in a wide variety of pediatric populations. In this article, we will review the advantages and disadvantages of the different RRT modalities and the technical aspects of providing pediatric RRT. In addition, we will review the use of RRT with extracorporeal membrane oxygenation, the use of continuous RRT in the critically ill child with acute kidney injury and fluid overload, and the use of RRT for the removal of toxins and treatment of inborn errors of metabolism.

Dialysis and pediatric acute kidney injury: choice of renal support modality

Dialytic intervention for infants and children with acute kidney injury (AKI) can take many forms. Whether patients are treated by intermittent hemodialysis, peritoneal dialysis or continuous renal replacement therapy depends on specific patient characteristics. Modality choice is also determined by a variety of factors, including provider preference, available institutional resources, dialytic goals and the specific advantages or disadvantages of each modality. Our approach to AKI has benefited from the derivation and generally accepted defining criteria put forth by the Acute Dialysis Quality Initiative (ADQI) group. These are known as the risk, injury, failure, loss, and end-stage renal disease (RIFLE) criteria. A modified pediatrics RIFLE (pRIFLE) criteria has recently been validated. Common defining criteria will allow comparative investigation into therapeutic benefits of different dialytic interventions. While this is an extremely important development in our approach to AKI, several fundamental questions remain. Of these, arguably, the most important are "When and what type of dialytic modality should be used in the treatment of pediatric AKI?" This review will provide an overview of the limited data with the aim of providing objective guidelines regarding modality choice for pediatric AKI. Comparisons in terms of cost, availability, safety and target group will be reviewed.

Reviews: The Current State of Nonuremic Applications for Extracorporeal Blood Purification

Despite the commonly accepted indications for hemodialysis and extracorporeal depuritive techniques, some clinicians have come to rely on blood purification for clinical states where the targeted substance for removal differs from uremic waste products. Over the last decade, a number of studies have emerged to help define the application of extracorporeal blood purification (ECBP) to these "nonuremic" indications. This review describes the application of extracorporeal blood purification in clinical states including sepsis, rhabdomyolysis, congestive heart failure, hepatic failure, tumor lysis syndrome, adult respiratory distress syndrome, intravenous contrast exposure, and lactic acidosis. Additional comments are provided to review existing literature on thermoregulation and osmoregulation, including acute brain injury.

Hyperosmolar solutions in continuous renal replacement therapy for hyperosmolar acute renal failure: a preliminary report

OBJECTIVE

To demonstrate the efficacy of hyperosmolar dialysis and prefilter replacement fluid solutions for continuous renal replacement therapies in the correction of hyperosmolar disorders in acute renal failure.

DATA SOURCE

An Institutional Review Board-approved pediatric acute renal failure database at the University of Michigan C. S. Mott Children's Hospital.

STUDY SELECTION

Three patients were identified meeting the inclusion criteria. The mean serum sodium concentration and plasma osmolality were 158 mmol/L and 357 mOsm/kg, respectively, at the time of initiation of renal replacement therapy. The sodium and/or dextrose concentrations of the dialysate or replacement fluids initially were increased and subsequently decreased to affect the solutions' calculated osmolalities in an effort to control the rate of decline of the patients' measured plasma osmolalities.

DATA EXTRACTION

The case patients' serum sodium concentrations and plasma osmolalities were measured. Additionally, the sodium and dextrose concentrations of the dialysate or replacement fluid were recorded and the solutions' osmolalities calculated.

DATA SYNTHESIS

The three patients experienced a mean rate of reduction of their serum sodium concentration and plasma osmolality of 0.5 mmol/L/hr and 1.6 mOsm/kg/hr, respectively.

CONCLUSIONS

Hyperosmolar dialysis or prefilter replacement fluid solutions can affect a slow decline in both the serum sodium and plasma osmolality in cases of hyperosmolar acute renal failure.

[Severe hypernatremia: survival without neurologic sequelae]

Hypernatremia is an electrolyte disturbance most frequently caused by excess water loss and less frequently by increased sodium intake. The few reported cases of severe hypernatremia (> 190 mEq/l) had an adverse outcome with high mortality and/or severe neurologic sequelae. The first case was a 7-year-old girl with renal failure undergoing continuous venovenous hemodiafiltration therapy who presented hypernatremia (216 mEq/l) after incorrect preparation of dialysis fluid. The patient was treated with hemodiafiltration and hypernatremia was resolved in 48 hours. She had a convulsive crisis without subsequent neurologic impairment. The second patient, a 3-year-old girl with pseudohypoaldosteronism type I and encephalopathy, had hypernatremia (203 mEq/l) due to erroneous sodium administration, which was corrected in 36 hours with intravenous fluid therapy. Her neurologic status was unchanged by treatment. We conclude that children with extreme hypernatremia survive without neurologic sequelae if treatment achieves a progressive decrease of natremia.