Random urine uric acid to creatinine and prediction of perinatal asphyxia: a meta-analysis

Energy Utilization in Premature Neonates Undergoing Screening for Retinopathy of Prematurity

BACKGROUND/OBJECTIVES

Premature neonates are at risk for retinopathy of prematurity (ROP) and routinely undergo screening exams that involve substantial physical manipulation, often causing significant signs of pain, despite pain-relieving interventions. It remains unclear whether these exams affect energy utilization, cellular hypoxia, and clinically significant events, and whether receiving supplemental oxygen affects these relationships. This work examines the effects of ROP screening on (1) urinary uric acid-to-creatinine concentration ratios ([UA]/[Cr]), a known marker of ATP degradation, hypoxia, and oxidative stress; and (2) clinically significant events (apnea, bradycardia, gastric residuals, and oxygen desaturations) in premature neonates on room air or oxygen support.

METHODS

This prospective pilot study included premature neonates requiring ROP screening examinations at Loma Linda University's NICU. Urinary [UA]/[Cr], measured by high-performance liquid chromatography, and clinical events, documented by prospective medical chart review, were analyzed pre- and post-exam in subjects on room air (n = 18) or on oxygen support (n = 20). Statistical analyses included a generalized linear mixed model for urinary [UA]/[Cr] and Wilcoxon signed rank tests for clinical events.

RESULTS

A significant time effect (p = 0.010) was observed for urinary [UA]/[Cr], with higher levels at 0-12 (p = 0.023) and 12-24 (p = 0.023) hours post-exam. Subjects receiving oxygen support had more total (p = 0.028) and more severe (p = 0.026) oxygen desaturations.

CONCLUSIONS

ROP examinations may increase energy utilization in premature neonates, with those receiving oxygen support being particularly susceptible to oxygen desaturations post-exam. Further research is needed to clarify the full impact of the procedure and to identify strategies to minimize stress associated with these screening examinations.

Urinary excretion of calcium, phosphate, magnesium, and uric acid in healthy infants and young children. Influence of feeding practices in early infancy

BACKGROUND

Reference values for urinary calcium (Ca) and other solutes/creatinine (Cr) ratios in infants and young children are scarce. Its variation with type of lactation administered, breastfed (BF) or formula (F), is incompletely known.

METHODS

A total of 511 spot urine samples from 136 children, aged 6 days to < 5 years, was collected. Urine was collected no fasting in infants < 18 months and first morning fasting in children aged 2.5-4 years. Urinary osmolality, Cr, urea, Ca, phosphate (P), magnesium (Mg), and uric acid (UA) were determined. Values are expressed as solute-to-Cr ratio.

RESULTS

Urinary values were grouped according to the child's age: 6-17 days (G1), 1-5 months (G2), 6-12 months (G3), 13-18 months (G4), and 2.5-4 years (G5). G1 was excluded; Ca/Cr and UA/Cr (95th percentile) decreased with age (G2 vs. G5) from 1.64 to 0.39 and 2.33 to 0.83 mg/mg, respectively. The P/Cr median rises significantly with age from 0.31 (G2) to 1.66 mg/mg (G5). Mg/Cr was similar in all groups (median 0.20, 95th percentile 0.37 mg/mg). Ca/Cr (95th percentile) of BF infants was 1.80 mg/mg (< 3 months) and 1.63 mg/mg (3-5 months), much higher than F infants (0.93 and 0.90 mg/mg, respectively). P/Cr and P/Ca were lower in BF infants.

CONCLUSIONS

Values for urinary Ca/Cr, P/Cr, Mg/Cr, and UA/Cr in infants and children < 5 years were updated. BF infants < 6 months showed higher Ca/Cr and lower P/Cr than F infants. New cutoff values to diagnose hypercalciuria in infants < 6 months, according to the type of lactation, are proposed.

The Urinary Uric Acid / Cr ratio as a marker of morbidity and mortality of preterm infants: a case-control study

BACKGROUND

Perinatal asphyxia is one of the main causes of preterm infant mortality. Some studies have shown that The Urinary Uric Acid / Cr (UUA/Cr) ratio may be used as an additional marker for perinatal asphyxia.This study intend to investigate the relationship of this ratio with outcomes of preterm infants admitted to NICU.

METHODS

This case-control study was carried on 102 preterm newborn infants with gestational age of 30 weeks to 33 weeks and 6 days admitted in the neonatal intensive care unit.The case group, consisted of 51 premature neonates with a history of intubation, cardiopulmonary resuscitation, mechanical ventilation and Nasal continuous positive airway pressure (NCPAP) at birth, were compared with 51 matched neonates. The UUA/Cr ratio was measured in the first 24 h after birth. Complications during hospitalization, duration of hospitalization, and final outcome were evaluated.

RESULTS

The mean level of UUA/Cr ratio in case and control group were 5.4 ± 4.1 and 3.6 9 ± 2.9 respectively and this difference was statistically significant (p = 0.014). The UUA/Cr ratio were significantly higher in females, cesarean section delivery, Apgar score ≥ 8, neonates without any complication and neonates with less than 10 days of hospitalization. However, this ratio has no predictive value for the incidence of complications during hospitalization and long-term hospital stay for infants of the case group.

CONCLUSIONS

The Urinary Uric Acid / Cr ratio in the first 24 h after birth in preterm neonates who underwent intubation, NCPAP or cardiopulmonary resuscitation was higher than healthy neonates.

Current Resources for Evidence-Based Practice, May 2020

An extensive review of new resources to support the provision of evidence-based care for women and infants. The current column includes a discussion of a new National Academy of Medicine report on planned place of birth and implications during the SARS-CoV-2 pandemic and commentaries on reviews focused on anorectal sexually transmitted infections and feeding methods following cleft lip repair in infants.

Effectiveness of theophylline administration in neonates with perinatal asphyxia: a meta-analysis

AIM

To evaluate the effects of prophylactic theophylline in renal function and survival rates of asphyxiated newborns.

METHODS

Medline, Scopus, Cochrane Central Register of Controlled Trials, Clinicaltrials.gov and Google Scholar databases were systematically searched. All randomized controlled trials evaluating the efficacy of theophylline in the prevention of perinatal asphyxia were selected.

RESULTS

A total of seven studies were included with a total of 458 asphyxiated neonates. Incidence of acute kidney injury was significantly lower in neonates receiving theophylline (OR: 0.24, 95% CI: [0.16, 0.36]), while mortality rates were similar between the two groups (OR: 0.86, 95% CI: [0.46, 1.62]). Theophylline administration was associated with significantly decreased serum creatinine levels (MD: -0.57 mg/dl, 95% CI: [-0.68, -0.46]) and elevated glomerular filtration rate (MD: 13.79 ml/min/1.73 m², 95% CI: [11.91, 15.68]) in the third day of life. Theophylline also lead to lower β2-microglobulin levels, higher urine output and negative fluid balance.

CONCLUSIONS

The present findings suggest the effectiveness of theophylline in ameliorating renal function of asphyxiated neonates. Future large-scale trials should assess potential long-term adverse outcomes in clinical practice.KeynotesAsphyxia is a major cause of acute kidney injury in neonatesAcute kidney injury is associated with adverse clinical outcomes in asphyxiated neonates.Theophylline administration leads to significantly lower incidence of acute kidney injury in asphyxiated neonates.