Hospital survey showed wide variations in therapeutic hypothermia for neonates in Germany

To feed or not to feed during therapeutic hypothermia in asphyxiated neonates: a systematic review and meta-analysis

The practice of withholding feed during therapeutic hypothermia (TH) in neonates with hypoxemic ischemic encephalopathy (HIE) is based on conventions rather than evidence. Recent studies suggest that enteral feeding might be safe during TH. We systematically compared the benefits and harms of enteral feeding in infants undergoing TH for HIE. We searched electronic databases and trial registries (MEDLINE, CINAHL, Embase, Web of Science, and CENTRAL) until December 15, 2022, for studies comparing enteral feeding and non-feeding strategies. We performed a random-effects meta-analysis using RevMan 5.4 software. The primary outcome was the incidence of stage II/III necrotizing enterocolitis (NEC). Other outcomes included the incidence of any stage NEC, mortality, sepsis, feed intolerance, time to full enteral feeds, and hospital stay. Six studies ((two randomized controlled trials (RCTs) and four nonrandomized studies of intervention (NRSIs)) enrolling 3693 participants were included. The overall incidence of stage II/III NEC was very low (0.6%). There was no significant difference in the incidence of stage II/III NEC in RCTs (2 trials, 192 participants; RR, 1.20; 95% CI: 0.53 to 2.71, I², 0%) and NRSIs (3 studies, no events in either group). In the NRSIs, infants in the enteral feeding group had significantly lower sepsis rates (four studies, 3500 participants, RR, 0.59; 95% CI: 0.51 to 0.67, I²-0%) and lower all-cause mortality (three studies, 3465 participants, RR: 0.43; 95% CI: 0.33 to 0.57, I²-0%) than the infants in the "no feeding" group. However, no significant difference in mortality was observed in RCTs (RR: 0.70; 95% CI: 0.28 to 1.74, I²-0%). Infants in the enteral feeding group achieved full enteral feeding earlier, had higher breastfeeding rates at discharge, received parenteral nutrition for a shorter duration, and had shorter hospital stays than the control group.  Conclusion: In late preterm and term infants with HIE, enteral feeding appears safe and feasible during the cooling phase of TH. However, there is insufficient evidence to guide the timing of initiation, volume, and feed advancement. What is Known: • Many neonatal units withhold enteral feeding during therapeutic hypothermia, fearing an increased risk of complications (feed intolerance and necrotizing enterocolitis). • The overall risk of necrotizing enterocolitis in late-preterm and term infants is extremely low (< 1%). What is New: • Enteral feeding during therapeutic hypothermia is safe and does not increase the risk of necrotizing enterocolitis, hypoglycemia, or feed intolerance. It may reduce the incidence of sepsis and all-cause mortality until discharge.

Comments on "Neonatal infratentorial subdural hematoma contributing to obstructive hydrocephalus in the setting of therapeutic cooling: A case report"

Although therapeutic hypothermia (TH) contributes significantly in the treatment of hypoxic ischemic encephalopathy (HIE), it could result in devastating complications such as intracranial hemorrhages. Laboratory examinations for possible coagulation disorders and early brain imaging can detect all these cases that are amenable to aggravation of HIE after the initiation of TH.

Mechanical Ventilation, Partial Pressure of Carbon Dioxide, Increased Fraction of Inspired Oxygen and the Increased Risk for Adverse Short-Term Outcomes in Cooled Asphyxiated Newborns

Neonates treated with therapeutic hypothermia (TH) following perinatal asphyxia (PA) suffer a considerable rate of disability and mortality. Several risk factors associated with adverse outcomes have been identified. Mechanical ventilation might increase the risk for hyperoxia and hypocapnia in cooled newborns. We carried out a retrospective study in 71 asphyxiated cooled newborns. We analyzed the association of ventilation status and adverse short-term outcomes and investigated the effect of the former on pCO₂ and oxygen delivery before, during and after TH. Death, abnormal findings on magnetic resonance imaging, and pathological amplitude-integrated electroencephalography traces were used to define short-term outcomes. The need for mechanical ventilation was significantly higher in the newborns with adverse outcomes (38% vs. 5.6%, p = 0.001). Compared to spontaneously breathing neonates, intubated newborns suffered from significantly more severe asphyxia, had significantly lower levels of mean minimum pCO₂ over the first 6 and 72 h of life (HOL) (p = 0.03 and p = 0.01, respectively) and increased supply of inspired oxygen, which was, in turn, significantly higher in the newborns with adverse outcomes (p < 0.01). Intubated newborns with adverse short-term outcomes had lower levels of pCO₂ over the first 36 HOL. In conclusion, need for mechanical ventilation was significantly higher in newborns with more severe asphyxia. In ventilated newborns, level of encephalopathy, lower pCO₂ levels, and increased oxygen supplementation were significantly higher in the adverse short-term outcomes group. Ventilatory parameters need to be carefully monitored in cooled asphyxiated newborns.

Effect of therapeutic hypothermia on renal and myocardial function in asphyxiated (near) term neonates: A systematic review and meta-analysis

BACKGROUND

Therapeutic hypothermia (TH) is a well-established neuroprotective therapy applied in (near) term asphyxiated infants. However, little is known regarding the effects of TH on renal and/or myocardial function.

OBJECTIVES

To describe the short- and long-term effects of TH on renal and myocardial function in asphyxiated (near) term neonates.

METHODS

An electronic search strategy incorporating MeSH terms and keywords was performed in October 2019 and updated in June 2020 using PubMed and Cochrane databases. Inclusion criteria consisted of a RCT or observational cohort design, intervention with TH in a setting of perinatal asphyxia and available long-term results on renal and myocardial function. We performed a meta-analysis and heterogeneity and sensitivity analyses using a random effects model. Subgroup analysis was performed on the method of cooling.

RESULTS

Of the 107 studies identified on renal function, 9 were included. None of the studies investigated the effects of TH on long-term renal function after perinatal asphyxia. The nine included studies described the effect of TH on the incidence of acute kidney injury (AKI) after perinatal asphyxia. Meta-analysis showed a significant difference between the incidence of AKI in neonates treated with TH compared to the control group (RR = 0.81; 95% CI 0.67-0.98; p = 0.03). No studies were found investigating the long-term effects of TH on myocardial function after neonatal asphyxia. Possible short-term beneficial effects were presented in 4 out of 5 identified studies, as observed by significant reductions in cardiac biomarkers and less findings of myocardial dysfunction on ECG and cardiac ultrasound.

CONCLUSIONS

TH in asphyxiated neonates reduces the incidence of AKI, an important risk factor for chronic kidney damage, and thus is potentially renoprotective. No studies were found on the long-term effects of TH on myocardial function. Short-term outcome studies suggest a cardioprotective effect.

Association of Routinely Measured Proinflammatory Biomarkers With Abnormal MRI Findings in Asphyxiated Neonates Undergoing Therapeutic Hypothermia

Background: The neuroprotective treatment effect of therapeutic hypothermia (TH) following perinatal asphyxia may be negatively influenced by neonatal sepsis and concomitant inflammation. We aimed to correlate routinely used blood biomarkers for perinatal sepsis in cooled asphyxiated newborns with MRI findings. Methods: Perinatal data was retrospectively collected from 67 cooled asphyxiated newborns. Levels of C-reactive protein (CRP), white blood cells and platelets were analyzed before, during and after TH. Interleukin-6 blood levels were analyzed before initiation of TH. Magnetic resonance imaging (MRI) on postnatal day 5-7 was used defining short-term outcome. Adverse outcome was defined as death or adverse MRI findings. Amplitude-integrated electroencephalography (aEEG) was additionally analyzed and correlated with short-term MRI outcome. Results: Forty-nine newborns had favorable short-term MRI outcome. Perinatal data referring to perinatal sepsis did not differ significantly between groups. IL-6 levels before initiation of TH and CRP levels on day three and after TH were significantly higher in newborns with adverse short-term MRI outcome. Males with adverse short-term MRI outcome had significantly increased CRP values at the end of the cooling phase. aEEG strongly correlated with short-term MRI outcome. Conclusion: Routinely used blood biomarkers may be helpful early identifying newborns at high risk of unfavorable outcome and in need of close neurodevelopmental follow-up.

Exploring Perinatal Asphyxia by Metabolomics

Brain damage related to perinatal asphyxia is the second cause of neuro-disability worldwide. Its incidence was estimated in 2010 as 8.5 cases per 1000 live births worldwide, with no further recent improvement even in more industrialized countries. If so, hypoxic-ischemic encephalopathy is still an issue of global health concern. It is thought that a consistent number of cases may be avoided, and its sequelae may be preventable by a prompt and efficient physical and therapeutic treatment. The lack of early, reliable, and specific biomarkers has up to now hampered a more effective use of hypothermia, which represents the only validated therapy for this condition. The urge to unravel the biological modifications underlying perinatal asphyxia and hypoxic-ischemic encephalopathy needs new diagnostic and therapeutic tools. Metabolomics for its own features is a powerful approach that may help for the identification of specific metabolic profiles related to the pathological mechanism and foreseeable outcome. The metabolomic profiles of animal and human infants exposed to perinatal asphyxia or developing hypoxic-ischemic encephalopathy have so far been investigated by means of ¹H nuclear magnetic resonance spectroscopy and mass spectrometry coupled with gas or liquid chromatography, leading to the identification of promising metabolomic signatures. In this work, an extensive review of the relevant literature was performed.