Management of renal dysfunction following term perinatal hypoxia-ischaemia

Training in neonatal neurocritical care: A case-based interdisciplinary approach

Interdisciplinary fetal-neonatal neurology (FNN) training strengthens neonatal neurocritical care (NNCC) clinical decisions. Neonatal neurological phenotypes require immediate followed by sustained neuroprotective care path choices through discharge. Serial assessments during neonatal intensive care unit (NICU) rounds are supplemented by family conferences and didactic interactions. These encounters collectively contribute to optimal interventions yielding more accurate outcome predictions. Maternal-placental-fetal (MPF) triad disease pathways influence postnatal medical complications which potentially reduce effective interventions and negatively impact outcome. The science of uncertainty regarding each neonate's clinical status must consider timing and etiologies that are responsible for fetal and neonatal brain disorders. Shared clinical decisions among all stakeholders' balance "fast" (heuristic) and "slow" (analytic) thinking as more information is assessed regarding etiopathogenetic effects that impair the developmental neuroplasticity process. Two case vignettes stress the importance of FNN perspectives during NNCC that integrates this dual cognitive approach. Clinical care paths evaluations are discussed for an encephalopathic extremely preterm and full-term newborn. Recognition of cognitive errors followed by debiasing strategies can improve clinical decisions during NICU care. Re-evaluations with serial assessments of examination, imaging, placental-cord, and metabolic-genetic information improve clinical decisions that maintain accuracy for interventions and outcome predictions. Discharge planning includes shared decisions among all stakeholders when coordinating primary care, pediatric subspecialty, and early intervention participation. Prioritizing social determinants of healthcare during FNN training strengthens equitable career long NNCC clinical practice, education, and research goals. These perspectives contribute to a life course brain health capital strategy that will benefit all persons across each and successive lifespans.

Perinatal asphyxia does not influence presepsin levels in neonates: A prospective study

AIM

To compare Presepsin (presepsin) levels in plasma and urine of uninfected newborn infants with perinatal asphyxia with those of controls.

METHODS

In this prospective study, we enrolled 25 uninfected full-term infants with perinatal asphyxia and 19 controls. We measured presepsin levels in whole blood or urine. In neonates with perinatal asphyxia, we compared presepsin levels in blood and urine at four time points.

RESULTS

In neonates with perinatal asphyxia, blood and urinary presepsin levels matched each other at any time point. At admission, the median presepsin value in blood was similar in both groups (p = 0.74), while urinary levels were higher in hypoxic neonates (p = 0.05). Perinatal asphyxia seemed to increase serum CRP and procalcitonin levels beyond normal cut-off but not those of presepsin.

CONCLUSION

In uninfected neonates with perinatal asphyxia, median blood and urinary presepsin levels matched each other at any point in the first 72 h of life and seemed to be slightly affected by the transient renal impairment associated with perinatal hypoxia in the first 12 h of life. Perinatal asphyxia did not influence presepsin levels within the first 72 h of life, while those of CRP and procalcitonin increased.

Multi-organ dysfunction scoring in neonatal encephalopathy (MODE Score) and neurodevelopmental outcomes

AIM

Neonatal encephalopathy (NE) is associated with an increased risk of multi-organ injury. The lack of standardised definitions for multi-organ dysfunction in NE hinders accurate quantification of these complications.

METHODS

A simple multi-organ dysfunction in neonatal encephalopathy scoring (MODE) system was created to include the cardiovascular, respiratory, gastrointestinal, haematological and neurological systems with a maximum score of 15. The MODE score was then compared with the grade of NE, Bayley Scales of Infant Development (Bayley-III) at 2 years of age and mortality. The Bayley score was used as it gave an objective score making it easier to compare the MODE score. Bayley score of <90 and/or abnormal MRI as an adverse outcome.

RESULTS

Infants with perinatal asphyxia (PA:n = 85) were prospectively enrolled (PA only n = 9; NE I = 23; NE II = 42; NE III = 11). Infants with higher MODE scores were significantly more likely to have moderate/severe NE (NE II/III: median scores (IQR) 7(5-10) versus mild NE 2 (1-3); p-value < 0.001) The MODE score was highly predictive of mortality (AUC 0.96, p-value = 0.002). Infants who had an abnormal neurological examination at discharge or abnormal Bayley-III scores had significantly higher MODE scores (p-value = 0.001).

CONCLUSION

Quantifying multi-organ injury is important to plan optimal early management and long-term follow-up. Additional use of clinical biomarkers may be useful as surrogate endpoints in future clinical trials and link to multi-organ longer-term developmental follow-up.

Hypothermia cannot ameliorate renal fibrosis after asphyxia in the newborn piglet

BACKGROUND

The effects of therapeutic hypothermia (TH) on renal function are not widely reported, especially in longer term animal models. The hypothesis of this study was that TH of the kidneys of hypoxic-ischemic newborn piglets would reduce pathological renal fibrosis.

METHODS

Twenty-five newborn piglets obtained within 24 h of birth were classified into a control group (n = 5), an hypoxic insult with normothermia (HI-NT) group (n = 12), and an hypoxic insult with TH (HI-TH) group (33.5 °C ± 0.5 °C for 24 h; n = 8). Five days after the insult, all piglets were sacrificed under deep anesthesia by isoflurane inhalation. The kidneys were perfused with phosphate-buffered paraformaldehyde and immersed in formalin buffer. Territory fibrosis was studied and scored in the renal medulla using Azan staining.

RESULTS

Fibrosis area scores (means ± standard deviations) based on Azan staining were 1.00 ± 0.46 in the control group, 2.85 ± 0.93 in the HI-NT group, and 3.58 ± 1.14 in the HI-TH group. The fibrosis area of the HI-NT and HI-TH groups was larger than that of the control. The HI-NT and HI-TH groups were not statistically different.

CONCLUSIONS

Renal fibrosis is affected by perinatal asphyxia and cannot be prevented by TH, based on histopathological findings.

Multi-Organ Dysfunction in Cerebral Palsy

Cerebral Palsy (CP) describes a heterogenous group of non-progressive disorders of posture or movement, causing activity limitation, due to a lesion in the developing brain. CP is an umbrella term for a heterogenous condition and is, therefore, descriptive rather than a diagnosis. Each case requires detailed consideration of etiology. Our understanding of the underlying cause of CP has developed significantly, with areas such as inflammation, epigenetics and genetic susceptibility to subsequent insults providing new insights. Alongside this, there has been increasing recognition of the multi-organ dysfunction (MOD) associated with CP, in particular in children with higher levels of motor impairment. Therefore, CP should not be seen as an unchanging disorder caused by a solitary insult but rather, as a condition which evolves over time. Assessment of multi-organ function may help to prevent complications in later childhood or adulthood. It may also contribute to an improved understanding of the etiology and thus may have an implication in prevention, interventional methods and therapies. MOD in CP has not yet been quantified and a scoring system may prove useful in allowing advanced clinical planning and follow-up of children with CP. Additionally, several biomarkers hold promise in assisting with long-term monitoring. Clinicians should be aware of the multi-system complications that are associated with CP and which may present significant diagnostic challenges given that many children with CP communicate non-verbally. A step-wise, logical, multi-system approach is required to ensure that the best care is provided to these children. This review summarizes multi-organ dysfunction in children with CP whilst highlighting emerging research and gaps in our knowledge. We identify some potential organ-specific biomarkers which may prove useful in developing guidelines for follow-up and management of these children throughout their lifespan.

Management of Multi Organ Dysfunction in Neonatal Encephalopathy

Neonatal Encephalopathy (NE) describes neonates with disturbed neurological function in the first post-natal days of life. NE is an overall term that does not specify the etiology of the encephalopathy although it often involves hypoxia-ischaemia. In NE, although neurological dysfunction is part of the injury and is most predictive of long-term outcome, these infants may also have multiorgan injury and compromise, which further contribute to neurological impairment and long-term morbidities. Therapeutic hypothermia (TH) is the standard of care for moderate to severe NE. Infants with NE may have co-existing immune, respiratory, endocrine, renal, hepatic, and cardiac dysfunction that require individualized management and can be impacted by TH. Non-neurological organ dysfunction not only has a negative effect on long term outcome but may also influence the efficacy of treatments in the acute phase. Post resuscitative care involves stabilization and decisions regarding TH and management of multi-organ dysfunction. This management includes detailed neurological assessment, cardio-respiratory stabilization, glycaemic and fluid control, sepsis evaluation and antibiotics, seizure identification, and monitoring and responding to biochemical and coagulation derangements. The emergence of new biomarkers of specific organ injury may have predictive value and improve the definition of organ injury and prognosis. Further evidence-based research is needed to optimize management of NE, prevent further organ dysfunction and reduce neurodevelopmental impairment.

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.

Kidney injury molecule-1 identifies antemortem injury in postmortem adult and fetal kidney

There is currently no technique to unambiguously diagnose antemortem kidney injury on postmortem examination since postmortem tissue damage and autolysis are common. We assessed the ability to detect kidney injury molecule-1 (KIM-1) expression in adult and fetal kidneys examined at autopsy. In adult kidneys ( n = 52 subjects), we found that the intensity of KIM-1 staining significantly correlated with the antemortem level of serum creatinine, and this was independent of the extent of tissue autolysis. In addition, kidneys from a total of 52 fetal/neonatal subjects, 30 stillborns and 22 liveborns, were assessed for KIM-1 staining. Given that serum creatinine is unreliable and often unavailable in fetuses and newborns, we assessed preterminal hypoxia in fetuses by the presence of squames in pulmonary alveoli and by required intubation. KIM-1 expression correlated with these clinical indexes of hypoxia. The expression of KIM-1 was seen in a majority of the fetal and neonatal autopsy kidneys (77%, 40/52) as early as 16 wk of gestation, even in the presence of autolysis. Thus KIM-1 is a specific and stable marker of antemortem tubular injury in kidneys of adults and fetuses despite postmortem autolysis.

Effect of hypothermia on interleukin-1 receptor antagonist pharmacodynamics in inflammatory-sensitized hypoxic-ischemic encephalopathy of term newborns

Background

Hypothermia is increasingly tested in several neurological conditions, such as neonatal encephalopathy, stroke, traumatic brain injury, subarachnoid hemorrhage, spinal cord injury, and neurological outcomes of cardiac arrest. Current studies aim to increase benefits of hypothermia with new add-on therapies including immunomodulatory agents. Hypothermia has been shown to affect the metabolism of commonly used drugs, including those acting on neuroimmune pathways.

Objective

This study focuses on the effect of hypothermia on interleukin-1 receptor antagonist pharmacodynamics in a model of neonatal encephalopathy.

Methods

The effect of hypothermia on (i) the tissue concentration of the interleukin-1 receptor antagonist, (ii) the interleukin-1 inflammatory cascade, and (iii) the neuroprotective potential of interleukin-1 receptor antagonist has been assessed on our rat model of neonatal encephalopathy resulting from inflammation induced by bacterial compound plus hypoxia-ischemia.

Results

Hypothermia reduced the surface of core and penumbra lesions, as well as alleviated the brain weight loss induced by LPS+HI exposure. Hypothermia compared to normothermia significantly increased (range 50–65%) the concentration of the interleukin-1 receptor antagonist within the central nervous system. Despite this increase of intracerebral interleukin-1 receptor antagonist concentration, the intracerebral interleukin-1-induced tumor necrosis factor-alpha cascade was upregulated. In hypothermic condition, the known neuroprotective effect of interleukin-1 receptor antagonist was neutralized (50 mg/kg/12 h for 72 h) or even reversed (200 mg/kg/12 h for 72 h) as compared to normothermic condition.

Conclusion

Hypothermia interferes with the pharmacodynamic parameters of the interleukin-1 receptor antagonist, through a bioaccumulation of the drug within the central nervous system and a paradoxical upregulation of the interleukin-1 pathway. These effects seem to be at the origin of the loss of efficiency or even toxicity of the interleukin-1 receptor antagonist when combined with hypothermia. Such bioaccumulation could happen similarly with the use of other drugs combined to hypothermia in a clinical context.

Renal dysfunction in early adulthood following birth asphyxia in male spiny mice, and its amelioration by maternal creatine supplementation during pregnancy

BACKGROUND

Acute kidney injury affects ~70% of asphyxiated newborns, and increases their risk of developing chronic kidney disease later in life. Acute kidney injury is driven by renal oxygen deprivation during asphyxia, thus we hypothesized that creatine administered antenatally would protect the kidney from the long-term effects of birth asphyxia.

METHODS

Pregnant spiny mice were fed standard chow or chow supplemented with 5% creatine from 20-d gestation (midgestation). One day prior to term (37-d gestation), pups were delivered by caesarean or subjected to intrauterine asphyxia. Litters were allocated to one of two time-points. Kidneys were collected at 1 mo of age to estimate nephron number (stereology). Renal function (excretory profile and glomerular filtration rate) was measured at 3 mo of age, and kidneys then collected for assessment of glomerulosclerosis.

RESULTS

Compared with controls, at 1 mo of age male (but not female) birth-asphyxia offspring had 20% fewer nephrons (P < 0.05). At 3 mo of age male birth-asphyxia offspring had 31% lower glomerular filtration rate (P < 0.05) and greater glomerular collagen IV content (P < 0.01). Antenatal creatine prevented these renal injuries arising from birth asphyxia.

CONCLUSION

Maternal creatine supplementation during pregnancy may be an effective prophylactic to prevent birth asphyxia induced acute kidney injury and the emergence of chronic kidney disease.

The Severity of Hypoxic-Ischemic Encephalopathy Correlates With Multiple Organ Dysfunction in the Hypothermia Era

OBJECTIVES

The objectives are to 1) determine whether there is a positive correlation between the severity of hypoxic-ischemic encephalopathy and multiple organ dysfunction and 2) evaluate the organ dysfunction pattern in infants with hypoxic-ischemic encephalopathy in the hypothermia era.

DESIGN

Retrospective observational study of prospective data collected between April 2009 and December 2012.

SETTING

The study took place in the neonatal ICU of Hospital Sant Joan de Déu-Hospital Clínic of Barcelona.

PATIENTS

Prospective consecutive newborns with greater than or equal to 36 weeks of gestation, greater than or equal to 1,800 g of weight at birth, and a diagnosis of hypoxic-ischemic encephalopathy was included.

INTERVENTIONS

Severity of hypoxic-ischemic encephalopathy was established before starting controlled hypothermia. Six organ systems and 23 clinical and laboratory variables were studied by means of an asymmetrical grading scale. Data were recorded daily during the first 72 hours of life.

MEASUREMENTS AND MAIN RESULTS

Seventy-nine patients were studied. All presented with multiple organ dysfunction on day 1. There were differences in the number of affected organs on day 1 according to hypoxic-ischemic encephalopathy stage (p < 0.001). Scale scores correlated positively with the severity of hypoxic-ischemic encephalopathy (area under the curve ranged from 0.77 to 0.87 on every day studied). There were significant differences in the severity of dysfunction of each organ system among the three hypoxic-ischemic encephalopathy stages (p < 0.05). Although the most frequently involved were hepatic and pH and electrolyte imbalance, the most severely affected were the respiratory and cardiovascular systems.

CONCLUSIONS

In the hypothermia era, multiple organ dysfunction continues to be almost universal in newborns with hypoxic-ischemic encephalopathy. There is a high correlation between the severity of hypoxic-ischemic encephalopathy and multiple organ dysfunction during the first 3 days of life. A high index of suspicion of relevant multiple organ dysfunction is required in infants admitted with a diagnosis of severe hypoxic-ischemic encephalopathy. Patients with moderate hypoxic-ischemic encephalopathy present wide variability in the severity of multiple organ dysfunction. In the absence of multiple organ dysfunction, a perinatal hypoxic-ischemic origin of acute severe neonatal encephalopathy should be carefully reconsidered.

Understanding the Full Spectrum of Organ Injury Following Intrapartum Asphyxia

Birth asphyxia is a significant global health problem, responsible for ~1.2 million neonatal deaths each year worldwide. Those who survive often suffer from a range of health issues including brain damage-manifesting as cerebral palsy (CP)-respiratory insufficiency, cardiovascular collapse, and renal dysfunction, to name a few. Although the majority of research is directed toward reducing the brain injury that results from intrapartum birth asphyxia, the multi-organ injury observed in surviving neonates is of equal importance. Despite the advent of hypothermia therapy for the treatment of hypoxic-ischemic encephalopathy (HIE), treatment options following asphyxia at birth remain limited, particularly in low-resource settings where the incidence of birth asphyxia is highest. Furthermore, although cooling of the neonate results in improved neurological outcomes for a small proportion of treated infants, it does not provide any benefit to the other organ systems affected by asphyxia at birth. The aim of this review is to summarize the current knowledge of the multi-organ effects of intrapartum asphyxia, with particular reference to the findings from our laboratory using the precocial spiny mouse to model birth asphyxia. Furthermore, we reviewed the current treatments available for neonates who have undergone intrapartum asphyxia, and highlight the emergence of maternal dietary creatine supplementation as a preventative therapy, which has been shown to provide multi-organ protection from birth asphyxia-induced injury in our preclinical studies. This cheap and effective nutritional supplement may be the key to reducing birth asphyxia-induced death and disability, particularly in low-resource settings where current treatments are unavailable.

Microarray expression profiles of genes in lung tissues of rats subjected to focal cerebral ischemia-induced lung injury following bone marrow-derived mesenchymal stem cell transplantation

Ischemia-induced stroke is the most common disease of the nervous system and is associated with a high mortality rate worldwide. Cerebral ischemia may lead to remote organ dysfunction, particular in the lungs, resulting in lung injury. Nowadays, bone marrow-derived mesenchymal stem cells (BMSCs) are widely studied in clinical trials as they may provide an effective solution to the treatment of neurological and cardiac diseases; however, the underlying molecular mechanisms remain unknown. In this study, a model of permanent focal cerebral ischemia-induced lung injury was successfully established and confirmed by neurological evaluation and lung injury scores. We demonstrated that the transplantation of BMSCs (passage 3) via the tail vein into the lung tissues attenuated lung injury. In order to elucidate the underlying molecular mechanisms, we analyzed the gene expression profiles in lung tissues from the rats with focal cerebral ischemia and transplanted with BMSCs using a Gene microarray. Moreover, the Gene Ontology database was employed to determine gene function. We found that the phosphoinositide 3-kinase (PI3K)-AKT signaling pathway, transforming growth factor-β (TGF-β) and platelet-derived growth factor (PDGF) were downregulated in the BMSC transplantation groups, compared with the control group. These results suggested that BMSC transplantation may attenuate lung injury following focal cerebral ischemia and that this effect is associated with the downregulation of TGF-β, PDGF and the PI3K-AKT pathway.

Renal function and novel urinary biomarkers in infants with neonatal encephalopathy

AIM

Perinatal asphyxia is associated with multi-organ injury including acute kidney injury (AKI). New urinary biomarkers may detect more subtle renal injury.

METHODS

Urinary biomarkers (albumin, beta-2 microglobulin, cystatin-C, epidermal growth factor, neutrophil gelatinase-associated lipocalin, osteopontin, uromodulin) were serially measured from days 1 to 7 in term infants with perinatal asphyxia and controls and compared to 'Kidney Disease Improving Global Outcome' scoring of renal injury and to encephalopathy grade.

RESULTS

A total of 255 urine samples were taken from infants exposed to perinatal asphyxia (n = 82) and term controls (n = 10). Thirty-nine infants underwent therapeutic hypothermia, four died and 30 infants had acute kidney injury. Infants with acute kidney injury had significantly higher levels of urinary albumin (day 2), cystatin-C (days 1, 2, 3 and 7), neutrophil gelatinase-associated lipocalin (days 2, 3 and 7) and osteopontin (days 2, 3 and 7) and lower epidermal growth factor and uromodulin (day 1) compared to those without AKI. Day 2 cystatin-C predicted AKI with an area under receiver operating characteristic curve of 0.89, p < 0.001, cut-off 9.8 × 10⁴  pg/mL. NE grade II/III infants had significantly elevated levels of urinary cystatin-C, neutrophil gelatinase-associated lipocalin and decreased EGF compared to grade 0/I infants.

CONCLUSION

Asphyxiated infants who develop acute kidney injury have significantly altered urinary biomarkers postnatally. Validation of neonatal AKI urinary biomarkers in a large prospective study is required. Long-term follow-up of infants post-asphyxial insult for chronic renal injury is advised.