Potassium regulation in the neonate

Metabolomic characteristics of cord blood from neonates with hyperkalemia after antenatal exposure to ritodrine and magnesium sulfate

In the management of pregnancy, ritodrine has been used to prevent preterm birth, and magnesium sulfate (MgSO4) has been used to prevent preterm labor and preeclampsia. Neonates born to mothers receiving these medications occasionally show an increase in serum potassium concentration. Recently, an elevated risk of neonatal hyperkalemia has been reported, particularly when ritodrine and MgSO4 are co-administered; however, the underlying mechanisms remain unclear. We conducted a retrospective cohort study of 142 preterm infants born between 24 and 36 weeks of gestation, categorized into groups exposed to antenatal ritodrine, MgSO4, both agents, or neither. In addition, we investigated the association between potassium levels and metabolites in the serum of umbilical cord blood from 33 infants exposed to antenatal ritodrine and MgSO4 using a metabolomic analysis. Our findings revealed a significant elevation in serum potassium concentration associated with metabolomic findings of activation of glycolysis and the derived metabolic routes in preterm neonates exposed to both ritodrine and MgSO4. Our data indicate that the concurrent administration of ritodrine and MgSO4 caused distinctive metabolic alterations, potentially leading to an additional increase in the intracellular potassium concentration in the fetus. Consequently, this mechanism may imply an elevation in serum potassium concentration postnatally through the redistribution of potassium.

Is it useful to wash stored red blood cells in cardiopulmonary bypass priming fluid for neonatal cardiac surgery? A single-centre retrospective study

BACKGROUND AND OBJECTIVES

Neonatal cardiac surgery requires careful consideration of cardiopulmonary bypass (CPB) priming fluid composition due to small blood volume and immature physiology. This study investigated the impact of allogeneic stored red blood cells (RBCs) processed using an autotransfusion system in CPB priming fluid for neonates.

MATERIALS AND METHODS

We compared perioperative parameters, inflammatory mediators, coagulation indicators, vasoactive-inotropic score (VIS) and clinical outcomes between neonates receiving unwashed (n = 56) and washed (n = 45) RBCs in CPB priming fluid. Regression models were used to assess the independent association between RBC washing and patient outcomes.

RESULTS

The autotransfusion system improved stored RBC quality. The washed group showed higher peak haematocrit (p < 0.01) and haemoglobin levels (p = 0.04) during CPB, an increased oxygen delivery index during rewarming (p < 0.05) and lower postoperative lactate levels and VIS (p < 0.05). Inflammatory (IL-6, IL-8 and IL-10) and coagulation parameters (D-dimer, fibrinogen and fibrin degradation product) fluctuated compared with baseline but did not significantly differ between groups. The washed group had a lower incidence of hyperlactacidaemia and delayed sternal closure at CPB weaning.

CONCLUSIONS

Adding washed allogeneic stored RBCs to neonatal CPB priming fluid reduced postoperative lactate elevation and VIS without early improvement in the inflammatory and coagulation systems.

Extremely rare cause of hyperkalemia: ileostomy‒induced hyperkalemia in extremely low birth weight infants

BACKGROUND

Hyperkalemia is one of the most serious electrolyte disturbances, and it can cause lethal cardiac arrhythmia. Although hyperkalemia associated with ileostomies has been reported in adults, to the best of our knowledge, it has not previously been reported in neonates.

CASE

We report ileostomy‒induced hyperkalemia that persisted during the ileostomy and resolved promptly after the closure of the ileostomy in two extremely low birth weight (ELBW) infants, with birth weights of 850 g and 840 g and gestational ages of 27 weeks and 27 weeks 6 days.

CONCLUSIONS

These cases highlight that disruption of intestinal integrity in ELBW infants may cause hyperkalemia. Ensuring the integrity of the gastrointestinal tract plays an important role in the treatment of electrolyte disorders such as hyperkalemia in ELBW infants with an ileostomy.

Cardiac arrest in a newborn: A case of pseudohypoaldosteronism

Pseudohypoaldosteronism (PHA) is a rare disease that can cause life-threatening hyperkalemia, which could lead to cardiac arrest and death if not recognized and treated quickly. We report a case of a neonate who was diagnosed with PHA type 1 and found to have a novel variant gene mutation on the NR3C2 gene. A 5-day-old newborn presented in cardiac arrest with severe hyperkalemia, hyponatremia, and metabolic acidosis. Hypothermia treatment was initiated due to suspected hypoxic-ischemic encephalopathy as well as electrolyte management with IV fluids and bicarbonate for the metabolic acidosis. Clinical suspicion and subsequent diagnostic testing led to a diagnosis of the renal form of PHA type 1. Genetic testing revealed a novel mutation on the NR3C2 gene of unknown significance (c.2891_2893dup plle964dup). The baby was discharged home on supplemental sodium and high-calorie formula for catch-up growth. Outpatient follow-up is ongoing, and the dose of sodium supplement was slowly decreased and discontinued at 2 years. There is evidence for developmental delays which is likely secondary to the cardiac arrest although the MRI during hospitalization was noted to be within normal limits. Having a high clinical suspicion for pseudohypoaldosteronism is paramount to initiating treatment and preventing potential cardiac arrest and death in these patients. Novel mutations such as this one need to be further explored to determine their significance with this disease.

Optimizing Nutrition in Neonates with Kidney Dysfunction

The nutritional management of neonates with kidney disease is complex. There may be significant differences in nutritional needs based on the duration and cause of kidney dysfunction, including acute kidney injury (AKI) and chronic kidney disease (CKD). Furthermore, the treatment modality, including acute (continuous renal replacement therapy and peritoneal dialysis [PD]) and chronic (intermittent hemodialysis and PD) approaches may differentially affect nutritional losses and dietary needs. In this review, we discuss the pathophysiology of compromised nutrition in neonates with AKI and CKD. We also summarize the existing data and consensus recommendations on the provision of nutrition to neonates with AKI and CKD. We highlight the paucity of data on micronutrient losses and the need for future prospective studies to enhance nutritional supplementation to hopefully improve outcomes in these patients.

Colistin use in a carbapenem-resistant Enterobacterales outbreak at a South African neonatal unit

Background

Colistin is increasingly prescribed for neonates with carbapenem-resistant Enterobacterales (CRE) infections.

Objectives

We described patient demographics, infection episodes, treatment and clinical outcomes, colistin related adverse events and relatedness of isolates in neonates with clinically confirmed or clinically suspected CRE infections.

Method

The authors retrospectively reviewed culture-confirmed and clinically suspected culture-negative CRE infections at a South African neonatal unit during a CRE outbreak.

Results

Fifty-three neonates (median gestational age 29 weeks and birth weight 1185 g) were included. Twenty-three of 53 neonates (43%) had culture-confirmed CRE (17 received colistin; 6 died without receiving colistin) and 30 (57%) received colistin for clinically suspected CRE infection but were ultimately culture-negative. Prior respiratory support and surgical conditions were present in 37/53 (70%) and 19/53 (36%) neonates, respectively. Crude mortality was high (20/53; 38%) with no significant difference between culture-confirmed CRE versus clinically suspected culture-negative CRE groups (10/23 [44%] vs 10/30 [33%]; p = 0.45). Hypomagnesaemia (10/38; 26%) and hypokalaemia (15/38; 40%) were frequent; acute kidney injury was rare (1/44; 2%). Three CRE infection clusters were identified by genotypic analysis of 20 available isolates (18 [90%] bla _NDM-1 [New Delhi metallo-beta-lactamase], 2 [10%] bla _OXA [oxacillinase]-48).

Conclusion

Neonates receiving colistin therapy were predominantly preterm, with multiple risk factors for infection. Colistin-associated electrolyte derangement was frequent. Over one-third of neonates died. Bla _NDM-1 was the most frequent carbapenemase gene identified in the outbreak isolates.

Contribution

Colistin was safely used during an Enterobacterales outbreak in predominantly premature and surgical neonates. The mortality was high.

Neonatal hyperkalemia associated with maternal ritodrine: A retrospective study

BACKGROUND

We recently reported on a late preterm infant born at 36 weeks' gestation with serious arrhythmia due to hyperkalemia associated with long-term maternal ritodrine administration. It is unknown whether ritodrine alone increases the risk of neonatal hyperkalemia in infants born at 34-36 weeks' gestation.

METHODS

This single-center, retrospective, cohort study enrolled late preterm infants (34-36 gestational weeks) born between 2004 and 2018. Cases with maternal magnesium sulfate use were not sufficient for statistical analysis and so were excluded from the study. Risk factors for the occurrence of hyperkalemia were determined based on clinical relevance and previous reports.

RESULTS

In all, 212 late preterm infants with maternal ritodrine use and 400 infants without tocolysis were included in the study. Neonatal hyperkalemia occurred in 5.7% (12/212) in the ritodrine group and 1.8% (7/400) in the control group. The risk of neonatal hyperkalemia was significantly increased by maternal ritodrine administration with a crude odds ratio (OR) of 3.37 (95% confidence interval [CI]: 1.30-8.69; p < 0.01) and an adjusted OR of 3.71 (95% CI: 1.41-9.74; p < 0.01) on multivariable analysis. Long-term tocolysis (≥28 days) with ritodrine increased the risk of neonatal hyperkalemia with 9.3% (11/118) of infants developing hyperkalemia (adjusted OR 4.86; 95% CI: 1.59-14.83; p < 0.01). Neonatal hyperkalemia was not found within 2 weeks of ritodrine administration.

CONCLUSION

This research suggests that late preterm infants born after long-term ritodrine administration are at risk of neonatal hyperkalemia and require special attention.

Aldosterone defects in infants and young children with hyperkalemia: A single center retrospective study

INTRODUCTION

Hyperkalemia is a rare but severe condition in young children and usually discovered as a result of hemolysis of the blood samples taken. However, patients with defects in either aldosterone biosynthesis or function can also present with hyperkalemia- as well hyponatremia-associated, and metabolic acidosis. It is a challenge to make an accurate diagnosis of these clinical conditions. We conducted this study to investigate the clinical and genetic features of aldosterone signaling defects associated hyperkalemia in young children.

METHOD

A retrospective review was conducted at the pediatric department of the First Affiliated Hospital of Guangxi Medical University from 2012 to 2022.

RESULTS

47 patients with hyperkalemia were enrolled, of which 80.9% (n = 38) were diagnosed with primary hypoaldosteronism, including congenital adrenal hyperplasia due to 21-hydroxylase deficiency (n = 32), isolated hypoaldosteronism (n = 1) due to CYP11B2 gene mutation and Xp21 contiguous gene deletion syndrome (n = 1). Additionally, 4 patients were clinically-diagnosed with primary adrenal insufficiency. Nine patients were confirmed with aldosterone resistance, of which one child was diagnosed with pseudohypoaldosteronism (PHA) type 1 with a mutation in the NR3C2 gene and 3 children were identified with PHA type 2 due to novel mutations in either the CUL3 or KLHL3 genes. Five patients had PHA type 3 because of pathologies of either the urinary or intestinal tracts.

CONCLUSIONS

The etiologies of infants with hyperkalemia associated with aldosterone defects were mostly due to primary hypoaldosteronism. An elevated plasma aldosterone level may be a useful biomarker for the diagnosis an aldosterone functional defect in patients presented with hyperkalemia. However, a normal plasma aldosterone level does rule out an aldosterone defect in either its biosynthesis or function, especially in young infants. Molecular genetic analyses can greatly help to clarify the complexity of disorders and can be used to confirm the diagnosis.

Fluid and Electrolyte Management in the Neonate: Potassium and Phosphorus

Maintenance of electrolyte balance in the neonate is challenging in the context of illness or prematurity. Imbalances in potassium and phosphorus can occur in neonates, ranging from benign and clinically insignificant to those that can be life-threatening. An individualized approach to fluid and electrolyte management is based on the neonate's gestational age, day of life, maintenance needs, deficits, and ongoing losses. This article reviews normal and abnormal potassium and phosphorus values along with management strategies. Using a case scenario, the reader can apply concepts outlined in this article to management of critically ill neonates with electrolyte disturbances.

Macronutrients and Micronutrients in Parenteral Nutrition for Preterm Newborns: A Narrative Review

Preterm neonates display a high risk of postnatal malnutrition, especially at very low gestational ages, because nutritional stores are less in younger preterm infants. For this reason nutrition and growth in early life play a pivotal role in the establishment of the long-term health of premature infants. Nutritional care for preterm neonates remains a challenge in clinical practice. According to the recent and latest recommendations from ESPGHAN, at birth, water intake of 70-80 mL/kg/day is suggested, progressively increasing to 150 mL/kg/day by the end of the first week of life, along with a calorie intake of 120 kcal/kg/day and a minimum protein intake of 2.5-3 g/kg/day. Regarding glucose intake, an infusion rate of 3-5 mg/kg/min is recommended, but VLBW and ELBW preterm neonates may require up to 12 mg/kg/min. In preterm infants, lipid emulsions can be started immediately after birth at a dosage of 0.5-1 g/kg/day. However, some authors have recently shown that it is not always possible to achieve optimal and recommended nutrition, due to the complexity of the daily management of premature infants, especially if extremely preterm. It would be desirable if multicenter randomized controlled trials were designed to explore the effect of early nutrition and growth on long-term health.

Chrononutrition and Breast Milk: A Review of Circadian Variation in Breast Milk Nutrient Composition

Objective

The objective of this literature review was to identify and summarize the current knowledge on the circadian variation of breast milk nutrients and the implications of these findings.

Method

A review of literature was conducted, including all relevant studies regardless of location and year of publication.

Results

The amino acids tyrosine, histidine, aspartic acid and phenylalanine and energy were observed to be higher during the day. Fat and the vitamins B-1, B-2, B-3, B-6, and B-12 were higher at night. Other studies have shown conflicting results or no circadian variation for certain nutrients. Poor reproducibility and small sample sizes affect the quality of existing research.

Conclusion

More research is needed, and longitudinal studies would help assess the effect of breast milk chrononutrition on the long-term health outcomes of infants.

A physiological approach to fluid and electrolyte management of the preterm infant: Review

Despite the fact that hundreds of thousands of preterm infants receive parenteral fluids each year, study of optimal fluid and electrolyte management in this population is limited. Compared to older children and adults, preterm infants have an impaired capacity to regulate water and electrolyte balance. Appropriate fluid and electrolyte management is critical for optimal care of low birth weight or sick infants, as fluid overload and electrolyte abnormalities pose significant morbidity. This review highlights basic physiological principles which need to be applied when prescribing parenteral fluids and builds upon published literature to outline a rational approach to initial fluid and electrolyte management of the preterm infant.

Nebulized salbutamol diminish the blood glucose fluctuation in the treatment of non-oliguric hyperkalemia of premature infants

BACKGROUND

Hyperkalemia is a risky and potentially life-threatening condition in pre-term infants. Glucose-insulin infusion has been considered a major therapeutic way for non-oligouric hyperkalemia but affects the stability of blood sugar level. We aimed to evaluate the effectiveness of salbutamol nebulization compared to glucose-insulin infusion for the treatment of non-oliguric hyperkalemia in premature infants.

METHODS

Forty premature infants (gestation age ≤36 weeks) with non-oliguric hyperkalemia (central serum potassium level greater than 6.0 mmol/L) within 72 h of birth were enrolled in this study. These infants were randomly assigned into two groups. One group received a regular insulin bolus with glucose infusion (Group A; n = 20), and the other received salbutamol (Ventolin) by nebulization (Group B; n = 20). Potassium level, blood sugar, heart rate, and blood pressure were recorded for each group before treatment and at 3, 12, 24, 48, and 72 h post-treatment.

RESULTS

The serum potassium levels were reduced after treatment in both groups. No significant changes in heart rate or blood pressure were observed in either group. The fluctuation in glucose levels was gentler in the salbutamol-treated group than in the glucose-insulin infusion group.

CONCLUSION

Salbutamol nebulization is not only as effective as glucose-insulin infusion for treating non-oliguric hyperkalemia in premature infants but can avoid potential side effects such as vigorous blood glucose fluctuations.