Prevention of excessive hypothermia in infants with hypoxic ischemic encephalopathy prior to admission to a quaternary care center: a neonatal outreach educational project

The Association Between Neonatal Intensive Care Unit Arrival Temperatures and Short-Term Outcomes of Neonates with Moderate and Severe Hypoxic-Ischemic Encephalopathy

Therapeutic hypothermia (TH) is the only treatment method that is known to reduce mortality and neurological sequela rates in newborns with moderate and severe hypoxic-ischemic encephalopathy (HIE). We aimed to evaluate the relationship between rectal temperatures measured upon arrival to our unit and short-term outcomes in newborns with HIE/TH. This was a retrospective study conducted between January 2022 and January 2023. The neonates were divided into three groups according to their rectal temperatures measured upon arrival at our unit as follows: Group 1) <33°C, Group 2) 33-34°C (group arriving at target temperature), and Group 3) >34°C. Short-term outcomes and mortality were compared between the groups. Group 1 consisted of 17 (19.8%) neonates, Group 2 consisted of 34 (39.5%) neonates, and Group 3 consisted of 35 (40.7%) neonates who had HIE and an indication for TH. Rectal temperature on arrival to the unit was not related to the rate of clinical convulsions, rates of abnormal attenuated electroencephalography and magnetic resonance imaging findings, rate of pulmonary hypertension, duration of mechanical ventilation and length of hospital stay. Although the mortality rate was 29% in Group 1, it was 3% and 6% in Groups 2 and 3, respectively (p = 0.016). No relationship was found between the rectal temperature upon arrival to the NICU and the short-term outcomes in HIE/TH neonates. However, the mortality rate in those who were overcooled was significantly higher compared with the other groups.

Neuroprotective therapies in the NICU in term infants: present and future

Outcomes of neonatal encephalopathy (NE) have improved since the widespread implementation of therapeutic hypothermia (TH) in high-resource settings. While TH for NE in term and near-term infants has proven beneficial, 30-50% of infants with moderate-to-severe NE treated with TH still suffer death or significant impairments. There is therefore a critical need to find additional pharmacological and non-pharmacological interventions that improve the outcomes for these children. There are many potential candidates; however, it is unclear whether these interventions have additional benefits when used with TH. Although primary and delayed (secondary) brain injury starting in the latent phase after HI are major contributors to neurodisability, the very late evolving effects of tertiary brain injury likely require different interventions targeting neurorestoration. Clinical trials of seizure management and neuroprotection bundles are needed, in addition to current trials combining erythropoietin, stem cells, and melatonin with TH. IMPACT: The widespread use of therapeutic hypothermia (TH) in the treatment of neonatal encephalopathy (NE) has reduced the associated morbidity and mortality. However, 30-50% of infants with moderate-to-severe NE treated with TH still suffer death or significant impairments. This review details the pathophysiology of NE along with the evidence for the use of TH and other beneficial neuroprotective strategies used in term infants. We also discuss treatment strategies undergoing evaluation at present as potential adjuvant treatments to TH in NE.

Association of outborn versus inborn birth status on the in-hospital outcomes of neonates treated with therapeutic hypothermia: A propensity score-weighted cohort study

OBJECTIVE

To compare the risk of in-hospital mortality and morbidity between outborn and inborn neonates treated with whole body hypothermia.

METHODS

The association of outborn birth status with in-hospital mortality and morbidity, prior to NICU discharge or transfer, was assessed in a large historical cohort of neonates who had therapeutic hypothermia initiated on the day of birth. The cohort was restricted to neonates born at ≥35 weeks gestational age from 2007 to 2018. Since the sample was non-random, inverse probability weighting (IPW) derived from propensity scores was used to reduce imbalance in baseline maternal and neonatal characteristics between outborn and inborn neonates. Cox proportional hazards regression was used to assess the association between outborn status and in-hospital mortality.

RESULTS

There were 4447 neonates included in the study (2463 outborn). Outborn status was not significantly associated with an increased risk of in-hospital mortality in the unadjusted cohort (HR = 1.17, 95% CI 0.97-1.42, p = 0.10) or IPW cohort (HR = 1.09, 95% CI 0.95-1.26, p = 0.22). However, in the IPW cohort, outborn neonates were significantly more likely to have seizures (28% vs 24%, p = 0.006), anticonvulsant exposure (46% vs 41%, p = 0.002), and gastrostomy tube placement (5.8% vs 3.8%, p = 0.009) during their newborn hospitalization.

CONCLUSION

Outborn status was not significantly associated with increased in-hospital mortality among neonates treated with whole body hypothermia. However, outborn neonates were more likely to have seizures, receive anticonvulsant treatment, and undergo gastrostomy tube placement. Further study is needed to better understand the etiologies of these outcome disparities and potential implications for long-term neurodevelopmental outcomes.

Ergebnisse des Hypothermienetzwerks des Universitätsklinikums Dresden von 2010–2017. Entwicklung der Hypothermietherapie bei Neugeborenen in Deutschland

Einleitung Die Hypothermiebehandlung (TH) verbessert bei Neugeborenen mit hypoxisch-ischämischer Enzephalopathie (HIE) das Outcome und sollte bei Hinweisen für eine perinatale Asphyxie und Zeichen einer moderaten oder schweren HIE angewendet werden.

Material/Methode Die Häufigkeit der HIE und der Anwendung der TH wurde aus den Daten der Neonatalerhebung und den Daten des 2010 etablierten Hypothermieregisters extrahiert. Letztere wurden darüber hinaus zur Analyse des kurzfristigen Outcomes herangezogen.

Ergebnisse Zwischen 2010 und 2017 schlossen sich 106 der 213 (Stand März 2020) deutschen Perinatalzentren dem Register an. Die Rückantwortquote lag zwischen 22 und 60%. Im Register wurden pro Jahr im Median 164 (IQR 115–224) TH bei Neugeborenen mit HIE erfasst, in der Neonatalerhebung 517 (382–664) bei 543 (432–583) Fällen von HIE. Seit 2014 lag die Zahl der TH über den berichteten Fällen von HIE. Nach TH bei klassischer Indikationsstellung verstarben 10,4% (8–13%) der Neugeborenen. 81% (78–82%) der Neugeborenen wurden nach Hause entlassen, 3,6% (3–5%) in eine Rehabilitationseinrichtung bzw. 5,4% (5–7%) in eine andere Klinik verlegt. Bei Entlassung wurden 89% (87–89%) der Patienten ausschließlich oral ernährt.

Diskussion Nach Etablierung der TH in die klinische Routine stieg die Zahl der behandelten Neugeborenen kontinuierlich an. Aktuell liegt die Zahl der TH über der Anzahl der Neugeborenen mit HIE, was nur schwer zu erklären ist, da das Vorliegen einer moderaten oder schweren HIE Voraussetzung für die TH ist. Die Daten des Hypothermieregisters zeigen für den untersuchten Zeitraum keine deutlichen Veränderungen bezüglich Mortalität oder neurologischem Outcome.

Umbilical cord blood troponin I, myoglobin and CK-MB in neonatal hypoxic ischemic encephalopathy and the clinical significance

Associations of serum S-100β, cystatin C (Cys-C) and C-reactive protein (CRP) with umbilical cord blood troponin I (TnI), myoglobin (Mb) and creatine kinase-MB (CK-MB) in neonatal hypoxic ischemic encephalopathy (NHIE) and the clinical significance were explored. A total of 40 patients with NHIE treated in the Binzhou Medical University Hospital were selected as observation group, while another 40 healthy neonates in the same period were selected as control group. The related data of all subjects were collected, and the levels of serum S-100β protein, CRP and Cys-C, and umbilical cord blood TnI, Mb and CK-MB were compared between the two groups. Associations of the neonatal behavioral neurological assessment (NBNA) score with the changes in serum S-100β protein, CRP and Cys-C and umbilical cord blood TnI, Mb and CK-MB were analyzed. The univariate and multivariate logistic regression analyses were performed to determine the risk factors for NHIE. In observation group, the levels of serum S-100β protein, CRP and Cys-C were significantly higher than those in control group, and the levels of umbilical cord blood TnI, Mb and CK-MB were also significantly higher than those in control group. The NBNA score was negatively correlated with the changes in serum S-100β protein, CRP and Cys-C as well as the umbilical cord blood TnI, Mb and CK-MB. The levels of serum S-100β protein, CRP and Cys-C, and umbilical cord blood TnI, Mb and CK-MB were related risk factors for NHIE. The increased levels of serum S-100β protein, CRP and Cys-C, and umbilical cord blood TnI, Mb and CK-MB were independent risk factors for NHIE. In NHIE patients, the levels of serum S-100β protein, CRP and Cys-C, and umbilical cord blood TnI, Mb and CK-MB all significantly increased, and they have negative correlation with the nervous system function after onset.