Why should we use a low sodium dialysis solution for peritoneal dialysis?

Overhydration is highly prevalent in patients on peritoneal dialysis (PD), with inappropriately high sodium load supposedly playing a central role in the pathophysiology of the conditions. Recent studies have revealed the novel role of the interstitium as a buffer system for sodium ions, and it has been reported that patients on dialysis, including PD, present increased levels of sodium in the interstitium, such as in subcutaneous tissue and muscle. Hence, therapy for correction of overhydration should target the excess extracellular volume and the excess sodium storage in the interstitium. The ultrafiltrate obtained using the currently available PD solutions is hypo- to isonatric as compared to serum, which is disadvantageous for prompt and efficient sodium removal from the body in patients with overhydration. In contrast, use of low sodium PD solutions is characterised by iso- to hypernatric ultrafiltrate, which may beneficial for reducing sodium storage in the interstitium. Trials of low sodium PD solutions have reported possible clinical merits, for example, decreased blood pressure, reduced dryness of mouth and decreased body water content as assessed using bioimpedance methods. Given these observations and the high prevalence of overhydration in current PD populations, it makes medical sense that low sodium solutions be positioned as the new standard solution in the future. However, for medical safety, that is, to avoid hyponatremia and excessive decreases in blood pressure, further studies are needed to establish the appropriate compositions and applications of low sodium solutions.

Successful treatment of cardiac arrest following hysteroscopic surgery using extracorporeal membrane oxygenation: A case report.

RATIONALE: Cardiac arrest caused by water intoxication syndrome following hysteroscopic surgery is a rare but life-threatening occurrence. Extracorporeal membrane oxygenation (ECMO) is rarely used to treat water intoxication syndrome in hysteroscopic surgery. Here, we successfully treated a patient with water intoxication syndrome following hysteroscopic surgery with ECMO. PATIENT CONCERNS: We report a rare case of cardiac arrest during hysteroscopic surgery treated with veno-venous (VV) ECMO. DIAGNOSIS: Water poisoning syndrome was diagnosed by electrolyte examination, the lowest value of serum sodium was 110.7 mmol/L. INTERVENTIONS: VV-ECMO was prescribed as a measure after traditional cardiopulmonary resuscitation. RESULTS: ECMO was successfully evacuated on day 5 and the patient was discharged on day 45. CONCLUSION: Mastering the hysteroscopic operative techniques and using a bipolar hysteroscopic generator, isotonic fluid, perfusion pressures less than 100 mm Hg, and local anesthesia may reduce the risk of hysteroscopic water intoxication syndrome. During hysteroscopic surgery, patients may experience cardiac arrest and fatal water intoxication syndrome. Even when traditional cardiopulmonary resuscitation is successful, VV ECMO may contribute to the recovery of brain function if oxygenation is not maintained.

Overhydration, underhydration, and total body sodium: A tricky "ménage a trois" in dialysis patients.

Overhydration is a frequent complication in dialysis patients. It has been linked with hypertension, left ventricular hypertrophy, arterial stiffness, atherosclerosis uremic cardiomyopathy, and all-cause mortality or cardiovascular morbidity. In addition, predialysis underhydration is also associated with increased risk of death in ESRD patients. In this context, the optimal evaluation of hydration status is a must. However, this mission is not easy or accurate. In the last 10 years, several new methods have been tested in dialysis patients, particularly bioimpedance and lung ultrasonography. The precise clinical value of these techniques in the daily care of hemodialysis patients is not obvious yet. Sodium is also an important piece of this puzzle. Salt intake and/or removal of sodium during dialysis are essential determinants of optimal hydration status. Recent studies have revealed that salt and water homeostasis is also dependent of tissue sodium storage-increased in hemodialysis patients. However, the significance of increased sodium tissue storage as a cardiovascular risk factor and the relationship between tissue sodium content and hard CV endpoint have not yet been elucidated yet.

"Bowel prep hyponatremia" - a state of acute water intoxication facilitated by low dietary solute intake: case report and literature review.

BACKGROUND: Symptomatic hyponatremia is considered a rare complication of oral bowel preparation for colonoscopy. The pathophysiology underlying this phenomenon has been widely regarded as a mere sequela of excessive arginine vasopressin (AVP) release. CASE PRESENTATION: This case describes a 61-year old woman who developed acute hyponatremic encephalopathy when preparing for elective outpatient lower endoscopy. She had had negligible oral solute intake for two days and ingested four liters of clear fluid within two hours. On admission, the patient was agitated and had slurred speech. Treatment with hypertonic saline lead to full recovery. A brisk aquaresis confirmed acute dilutional hyponatremia. CONCLUSION: Apart from elevated AVP-levels, the amount and speed of fluid intake and concomitant low-solute intake constitute important risk factors in the development of clinically relevant hyponatremias in patients undergoing colonoscopies. Understanding that the cause of sodium imbalance in this scenario is multifactorial and complex is pivotal to recognizing and ideally preventing this complication, for which we propose the term "bowel prep hyponatremia".

Methylphenidate Overdose Causing Secondary Polydipsia and Severe Hyponatremia in an 8-Year-Old Boy.

OBJECTIVE: Attention deficit hyperactivity disorder (ADHD) is an increasingly common diagnosis of childhood that manifests with symptoms that affect cognitive, academic, behavioral, emotional, and social functioning. There are a multitude of pharmaceutical therapies to choose from when managing this condition, and though many studies on the safety and efficacy of these medications have been published, adverse effects still occur. CASE: This case discusses a previously healthy 8-year-old boy who had been prescribed 20-mg lisdexamfetamine dimesylate for ADHD however mistakenly took his brother's 36-mg methylphenidate extended-release tablets, resulting in hyperhidrosis, excessive thirst, polydipsia, and combative behavior that began within 3 hours of ingestion. He was evaluated at a community hospital emergency department and given lorazepam due to agitation and combativeness before discharge. However, he returned with hypothermia, hyponatremia, and status epilepticus resulting in intubation. Patient was transferred to our facility where a computer tomography of his head was negative and hyponatremia was corrected with 3% NaCl saline solution. A lumbar puncture was performed due to temperature instability before starting broad-spectrum antibiotics. Cerebrospinal fluid findings were normal, and he was extubated at 18 hours postingestion. Patient was discharged home after 3 days with no residual symptoms. DISCUSSION/CONCLUSIONS: Though both lisdexamfetamine dimesylate and methylphenidate are widely used among pediatricians today for treatment of ADHD, reports of life-threatening water intoxication as a result of overdose is rare. Studies have reported that severe 3,4-methylenedioxymethamphtamine toxicity in adults is associated with syndrome of inappropriate diuretic hormone (SIADH) secretion, hyponatremia, and seizures, along with serotonin-induced transient elevation in antidiuretic hormone. Adult schizophrenics who receive psychostimulants have also been shown to develop polydipsia with hyponatremia. Although the use of psychostimulants in adult schizophrenic patients has been studied, literature on toxicity and effects in the pediatric psychiatric population is scarce. We would suggest that this patient's polydipsia and hyponatremia are most likely a result of his ingestion of a toxic dose of a long-acting agent known to cause secondary psychosis.

Motor neuron disease mortality rates in U.S. states are associated with well water use.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with an unknown cause and invariably fatal outcome. We sought to evaluate a correlation between motor neuron disease (MND) mortality rates and residential radon levels that was previously reported for counties in the United Kingdom. We examined the relationships between age-adjusted MND mortality rates in U.S. states with residential radon levels, well water use, and other variables using structural equation modeling. We observed a significant correlation between MND mortality rates and radon levels. However, in structural equation models, radon did not have a significant, direct effect on MND mortality rates. Conversely, MND mortality rates were significantly and directly predicted by race and by the percentage of the population of each state using well water (p < 0.001 and p = 0.022). We observed similar, significant effects for well water use and MND mortality for males and females separately (p < 0.05). In conclusion, we hypothesize that the association of MND mortality rates with well water use reflects contamination of wells with Legionella, a bacterium common in well water that is known to cause neurologic disease. A Legionella hypothesis is a biologically plausible cause of ALS and suggests new avenues for etiologic research.

[Can water be poisonous?]. / Kann man sich mit Wasser intoxikieren? - Fall 5 / 2015.

HISTORY AND ADMISSION FINDINGS: Two female patients aged over 80 years developed central nervous symptoms after drinking large amounts of water (more than 3 l per day). INVESTIGATIONS: Both had a hypoosmolar hyponatremia that was induced by concomitant treatment with hydrochlorothiazid (HCT) in the one case and in the other case relied on a distal tubular damage due to reflux nephropathy. DIAGNOSIS, TREATMENT AND COURSE: Hyponatremia was corrected after withdrawal of HCT and fluid restriction and central nervous symptoms disappeared rapidly. CONCLUSIONS: Distal tubular urinary dilution can be disturbed by HCT and parenchymal renal disease and can result in symptomatic hyponatremia after drinking large amounts of water.

Dialysate Sodium: Choosing the Optimal Hemodialysis Bath.

Fluid overload in patients undergoing hemodialysis contributes to cardiovascular morbidity and is a major cause of hospitalizations. It is often addressed by reinforcing the importance of a low-salt diet with patients and challenging estimated dry weights. More recently, interest has shifted toward the dialysate sodium prescription as a strategy to improve fluid overload and its adverse sequelae. The availability of high-flux high-efficiency dialysis in conjunction with the need to ensure its tolerability for patients has resulted in an increase in dialysate sodium prescriptions from 120 to ≥140 mEq/L. However, we are now tackling the unforeseen consequences associated with high dialysate sodium prescriptions. High dialysate sodium concentration is associated with high interdialytic weight gain, a commonly used surrogate for hypervolemia contributing to hypertension. The association between mortality and high dialysate sodium concentration remains controversial with conflicting data. It is clear that fluid management in the diverse end-stage renal disease population is extremely complex and more clinical trials are needed. In the meantime, while patients require treatments and clinical decisions need to be made, this review article attempts to summarize the current evidence for individualized dialysate sodium prescriptions based on patients' volume status, comorbid conditions, plasma sodium level, and hemodynamic response to dialysis therapy.

Fatal water intoxication and cardiac arrest in runners during marathons: prevention and treatment based on validated clinical paradigms.

Cerebral edema due to exercise-associated hyponatremia and cardiac arrest due to atherosclerotic heart disease cause rare marathon-related fatalities in young female and middle-aged male runners, respectively. Studies in asymptomatic middle-aged male physician-runners during races identified inflammation due to skeletal muscle injury after glycogen depletion as the shared underlying cause. Nonosmotic secretion of arginine vasopressin as a neuroendocrine stress response to rhabdomyolysis mediates hyponatremia as a variant of the syndrome of inappropriate antidiuretic hormone secretion. Fatal hyponatremic encephalopathy in young female runners was curtailed using emergent infusion of intravenous hypertonic (3%) saline to reverse cerebral edema on the basis of this paradigm. This treatment was arrived at through a consensus process within the medical community. An increasing frequency of cardiac arrest and sudden death has been identified in middle-aged male runners in 2 studies since the year 2000. Same-aged asymptomatic male physician-runners showed post-race elevations in interleukin-6 and C-reactive protein, biomarkers that predict acute cardiac events in healthy persons. Hypercoagulability with in vivo platelet activation and release of cardiac troponin and N-terminal pro-brain natriuretic peptide were also observed post-race in these same subjects. High short-term risk for atherothrombosis during races as shown by stratification of biomarkers in asymptomatic men may render nonobstructive coronary atherosclerotic plaques vulnerable to rupture. Pre-race aspirin use in this high-risk subgroup is prudent according to conclusive evidence for preventing first acute myocardial infarctions in same-aged healthy male physicians. On the basis of validated clinical paradigms, taking a low-dose aspirin before a marathon and drinking to thirst during the race may avert preventable deaths in susceptible runners.

Recurrent rhabdomyolysis in a teenager with psychosis-intermittent hyponatremia-polydipsia syndrome.

OBJECTIVE: To report a case of recurrent hyponatremia and rhabdomyolysis in a teenager with psychogenic polydipsia. CASE SUMMARY: A 16-year-old boy was admitted with recurrent episodes of hyponatremia and rhabdomyolysis secondary to psychogenic polydipsia. He was treated with hypertonic saline, intravenous fluids, and supportive care. DISCUSSION: Psychogenic polydipsia is a condition characterized by compulsive drinking. Severe hyponatremia is a rare, but serious complication in patients with psychogenic polydipsia. Failure in cell volume regulatory mechanisms, defective osmoregulation, defective urinary dilution, and enhanced secretion of vasopressin are believed to play a role in the development of hyponatremia. Rhabdomyolysis can complicate severe hyponatremia, although the exact mechanism is not known. Antipsychotic drugs are also implicated in rhabdomyolysis. CONCLUSIONS: Severe hyponatremia and rhabdomyolysis can complicate psychogenic polydipsia. Patients receiving antipsychotic drugs with concomitant severe hyponatremia need to be monitored for rhabdomyolysis.

Sodium-induced hyperhydration decreases urine output and improves fluid balance compared with glycerol- and water-induced hyperhydration.

Before 2010, which is the year the World Anti-Doping Agency banned its use, glycerol was commonly used by athletes for hyperhydration purposes. Through its effect on osmoreceptors, we believe that sodium could prove a viable alternative to glycerol as a hyperhydrating agent. Therefore, this study compared the effects of sodium-induced hyperhydration (SIH), glycerol-induced hyperhydration (GIH) and water-induced hyperhydration (WIH) on fluid balance responses. Using a randomized, double-blind and counterbalanced protocol, 17 men (21 ± 3 years, 64 ± 6 kg fat-free mass (FFM)) underwent three 3-h hyperhydration protocols during which they ingested, over the first 60-min period, 30 mL/kg FFM of water with (i) an artificial sweetener (WIH); (ii) an artificial sweetener + 7.45 g/L of table salt (SIH); or (iii) an artificial sweetener + 1.4 g glycerol/kg FFM (GIH). Changes in body weight (BW), urine production, fluid retention, hemoglobin, hematocrit, plasma volume, and perceptual variables were monitored throughout the 3-h trials. After 3 h, SIH was associated with significantly (p < 0.05) lower hemoglobin, hematocrit (SIH: 43.1% ± 2.8%; GIH: 44.9% ± 2.4%), and urine production, as well as greater BW, fluid retention (SIH: 1144 ± 294 mL; GIH: 795 ± 337 mL), and plasma volume (SIH: 11.9% ± 12.0%; GIH: 4.0% ± 6.0%) gains, compared with GIH and WIH. No significant differences in heart rate or abdominal discomfort were observed between treatments. In conclusion, our results indicate that SIH is a superior hyperhydrating technique than, and proves to be a worthwhile alternative to, GIH.

Acute symptomatic hyponatremia in a flight attendant.

Acute symptomatic hyponatremia after thiazide diuretic initiation is a medical emergency. Here we describe the case of a flight attendant who developed acute hyponatremia during a flight and the potential risk factors for developing this condition. A 57-year-old flight attendant with history of essential hypertension was recently started on a thiazide diuretic. As she did routinely when working, she increased her water intake during a flight from London to Mexico City. She complained of nausea and headache during the flight. Upon arrival, she developed severe disorientation and presented to the hospital emergency room (ER) with a Glasgow scale of 12, hypoxia, and a generalized tonic clonic seizure. Her laboratory results on arrival were consistent with severe hyponatremia (serum Na 116 mEql/L) and severe cerebral edema by CT scan. She was treated with hypertonic saline, with complete resolution of the neurologic symptoms. We describe high water intake and hypoxia related to decreased partial pressure of oxygen in the cabin as the two main risk factors for thiazide-induced acute hyponatremia in this case.

Strategies for removing fluids during hemodialysis.

Dry weight has most frequently been defined by the patient becoming symptomatic when fluid removal is attempted Hypervolemia and fluid removal require ongoing evaluation and the use of a number of strategies. This article reviews strategies for removing fluid during hemodialysis, hemodynamics of fluid removal, and interventions associated with the strategies for fluid removal.