Trends and predictors of in-hospital mortality among babies with hypoxic ischaemic encephalopathy at a tertiary hospital in Nigeria: A retrospective cohort study

Effectiveness and Safety of Dexmedetomidine in Neonates With Hypoxic Ischemic Encephalopathy Undergoing Therapeutic Hypothermia

OBJECTIVE

The objective of this study was to evaluate and compare the effectiveness and safety of dexmedetomidine as monotherapy between neonates with mild hypoxic ischemic encephalopathy (HIE) and moderate to severe HIE treated with therapeutic hypothermia (TH).

METHODS

This retrospective study included neonates of gestational age ≥36 weeks with a diagnosis of HIE and undergoing TH between January 2014 and December 2021. Patients were included if they received at least 6 hours of continuous sedation with dexmedetomidine. Baseline characteristics, dose and duration of medication, adverse events, liver and kidney function tests, and hospital course were reviewed.

RESULTS

Of the 97 neonates included, 46 had mild, 42 had moderate, and 9 had severe HIE. Dexmedetomidine was initiated at a median 5 hours of life, and the median infusion duration was 77 (46-87) hours. Fifty-two (53.6%) required at least 1 breakthrough opioid or sedative during the first 24 hours of dexmedetomidine infusion. Overall, 40 patients (41.2%) had at least 1 bradycardia episode with heart rate <80 beats/min and 14 patients (14.4%) had heart rate <70 beats/min. Hypotension was experienced by 7 patients (7.2%). Fifty-two patients (53.6%) were intubated in the delivery room and 33/52 (63.5%) were extubated on day of life 1 during dexmedetomidine infusion.

CONCLUSIONS

Dexmedetomidine as monotherapy was effective and safe sedation for infants with HIE undergoing hypothermia. The most common side effect of dexmedetomidine was bradycardia. -Dexmedetomidine may be considered as first and single agent for neonates with HIE undergoing TH.

Gross and Histologic Placental Abnormalities Associated With Neonatal Hypoxic-Ischemic Encephalopathy

OBJECTIVE

To elucidate particular placental pathology findings that are associated with hypoxic ischemic encephalopathy (HIE) and determine which patterns are associated with adverse fetal/neonatal outcomes.

STUDY DESIGN

Multi-institutional retrospective case-control study of newborns with HIE (2002-2022) and controls. Four perinatal pathologists performed gross and histologic evaluation of placentas of cases and controls.

RESULTS

A total of 265 placentas of neonates with HIE and 122 controls were examined. Infants with HIE were more likely to have anatomic umbilical cord abnormalities (19.7% vs 7.4%, P = .003), fetal inflammatory response in the setting of amniotic fluid infection (27.7% vs 13.9%, P = .004), and fetal vascular malperfusion (30.6% vs 9.0%, P = <.001) versus controls. Fetal vascular malperfusion with maternal vascular malperfusion was more common in those who died of disease (P = .01).

CONCLUSION

Placental pathology examination of neonates with HIE may improve our understanding of this disorder and its adverse outcomes.

N6-methyladenosine demethylase FTO regulates synaptic and cognitive impairment by destabilizing PTEN mRNA in hypoxic-ischemic neonatal rats

Hypoxic-ischemic brain damage (HIBD) can result in significant global rates of neonatal death or permanent neurological disability. N6-methyladenosine (m6A) modification of RNA influences fundamental aspects of RNA metabolism, and m6A dysregulation is implicated in various neurological diseases. However, the biological roles and clinical significance of m6A in HIBD remain unclear. We currently evaluated the effect of HIBD on cerebral m6A methylation in RNAs in neonatal rats. The m6A dot blot assay showed a global augmentation in RNA m6A methylation post-HI. Herein, we also report on demethylase FTO, which is markedly downregulated in the hippocampus and is the main factor involved with aberrant m6A modification following HI. By conducting a comprehensive analysis of RNA-seq data and m6A microarray results, we found that transcripts with m6A modifications were more highly expressed overall than transcripts without m6A modifications. The overexpression of FTO resulted in the promotion of Akt/mTOR pathway hyperactivation, while simultaneously inhibiting autophagic function. This is carried out by the demethylation activity of FTO, which selectively demethylates transcripts of phosphatase and tensin homolog (PTEN), thus promoting its degradation and reduced protein expression after HI. Moreover, the synaptic and neurocognitive disorders induced by HI were effectively reversed through the overexpression of FTO in the hippocampus. Cumulatively, these findings demonstrate the functional importance of FTO-dependent hippocampal m6A methylome in cognitive function and provides novel mechanistic insights into the therapeutic potentials of FTO in neonatal HIBD.

Evaluation of syringin's neuroprotective effect in a model of neonatal hypoxic-ischemic brain injury

Background/aim

A significant cause of mortality and morbidity in the neonatal era is hypoxic-ischemic encephalopathy (HIE). This study examined the histopathological analysis and neuroprotective impact of syringin (SYR) in an experimental HIE rat model.

Material and methods

On the 7th postnatal day, 24 Wistar albino rats were evaluated in 3 groups using the HIE model under gas anesthesia. In the experiment, Group A received 10 mg/kg SYR plus dimethyl sulfoxide (DMSO), Group B received DMSO only, and Group C served as a sham group. Immunohistochemical techniques were used to assess apoptotic cell measurement and proinflammatory cytokines (TNF-α and IL-1β primary antibodies).

Results

Rats suffering from hypoxic-ischemic brain damage had their apoptosis assessed. The SYR and sham groups had statistically fewer cells undergoing apoptosis (p < 0.001). There was no difference between the groups in terms of IL-1β and TNF-α during immunohistochemical staining. Neuronal degeneration was significantly lower in the histological evaluation of the hippocampus in the SYR group (p = 0.01). A statistically significant difference (p = 0.01) was observed between the SYR and the control groups regarding pericellular and perivascular edema.

Conclusion

SYR reduced apoptosis, perivascular and pericellular edema, and neuronal degeneration in rat cerebral tissue. These results raise the possibility that SYR may have a neuroprotective effect on the harm brought on by HIE. This is the first investigation of SYR's function within the HIE paradigm.

Risk factors of mortality in neonates with neonatal encephalopathy in a tertiary newborn care unit in Zimbabwe over a 12-month period

Neonatal encephalopathy (NE) accounts for ~23% of the 2.4 million annual global neonatal deaths. Approximately 99% of global neonatal deaths occur in low-resource settings, however, accurate data from these low-resource settings are scarce. We reviewed risk factors of neonatal mortality in neonates admitted with neonatal encephalopathy from a tertiary neonatal unit in Zimbabwe. A retrospective review of risk factors of short-term neonatal encephalopathy mortality was conducted at Sally Mugabe Central Hospital (SMCH) (November 2018 -October 2019). Data were gathered using a tablet-based data capture and quality improvement newborn care application (Neotree). Analyses were performed on data from all admitted neonates with a diagnosis of neonatal encephalopathy, incorporating maternal, intrapartum, and neonatal risk predictors of the primary outcome: mortality. 494/2894 neonates had neonatal encephalopathy on admission and were included. Of these, 94 died giving a neonatal encephalopathy-case fatality rate (CFR) of 190 per 1000 admitted neonates. Caesarean section (odds ratio (OR) 2.95(95% confidence interval (CI) 1.39-6.25), convulsions (OR 7.13 (1.41-36.1)), lethargy (OR 3.13 (1.24-7.91)), Thompson score "11-14" (OR 2.98 (1.08-8.22)) or "15-22" (OR 17.61 (1.74-178.0)) were significantly associated with neonatal death. No maternal risk factors were associated with mortality. Nearly 1 in 5 neonates diagnosed with neonatal encephalopathy died before discharge, similar to other low-resource settings but more than in typical high-resource centres. The Thompson score, a validated, sensitive and specific tool for diagnosing neonates with neonatal encephalopathy was an appropriate predictive clinical scoring system to identify at risk neonates in this setting. On univariable analysis time-period, specifically a period of staff shortages due to industrial action, had a significant impact on neonatal encephalopathy mortality. Emergency caesarean section was associated with increased mortality, suggesting perinatal care is likely to be a key moment for future interventions.

Trends of neonatal hypoxic-ischemic encephalopathy prevalence and associated risk factors in the United States, 2010 to 2018

BACKGROUND

Despite recent advances in perinatal care, neonatal hypoxic-ischemic encephalopathy remains one of the most common causes of neonatal morbidity and mortality. The trends for prevalence and mortality of neonatal hypoxic-ischemic encephalopathy have not been examined in the era of therapeutic hypothermia in the United States.

OBJECTIVE

This study aimed to determine (1) the overall and gestational age-specific (35-36, ≥37, and >42 weeks) trends of hypoxic-ischemic encephalopathy prevalence and use of therapeutic hypothermia, (2) the trends of mortality in association with hypoxic-ischemic encephalopathy, (3) the confounding variables associated with hypoxic-ischemic encephalopathy, and (4) the clinical outcomes of neonates with hypoxic-ischemic encephalopathy.

STUDY DESIGN

This study used National Inpatient Sample datasets from 2010 to 2018. Moreover, the study included infants with a gestational age of ≥35 weeks with a documented hypoxic-ischemic encephalopathy diagnosis (mild, moderate, severe, or unspecified). We calculated trends in hypoxic-ischemic encephalopathy prevalence and the use of therapeutic hypothermia using chi-squared testing. Furthermore, this study used logistic regression models to control for confounders.

RESULTS

A total of 32,180,617 infants were included, of which 31,249,100 were term (gestational age of ≥37 weeks) and 931,517 were late preterm (gestational age of 35-36 weeks). Hypoxic-ischemic encephalopathy prevalence slightly increased from 0.093% in 2010-2012 to 0.097% in 2016-2018 (P=.01) in term infants and did not significantly change in late preterm infants (P=.20). There were 6235 term infants (20.8%) and 449 late preterm infants (21.1%) with hypoxic-ischemic encephalopathy who were managed with therapeutic hypothermia. The use of therapeutic hypothermia in both term and late preterm infants has increased over the years (P<.01). The mortality rate with hypoxic-ischemic encephalopathy decreased over time from 11.5% to 12.3% between 2010 to 2012, and from 8.3% to 10.6% betweenn 2016 to 2018 (P<.01). The factors with the strongest association with hypoxic-ischemic encephalopathy were placental infarction or insufficiency (odds ratio, 144; 95% confidence interval, 134-157), placental abruption (odds ratio, 101; 95% confidence interval, 91-112), cord prolapse (odds ratio, 74; 95% confidence interval, 65-84), and maternal anemia (odds ratio, 26; 95% confidence interval, 20-37).

CONCLUSION

Hypoxic-ischemic encephalopathy prevalence in neonates essentially remained the same at 1 per 1000 live births. The use of therapeutic hypothermia increased, and the mortality rate decreased in infants with hypoxic-ischemic encephalopathy. The identification of hypoxic-ischemic encephalopathy-associated factors should promote increased vigilance to optimize newborn outcomes.

Short-term outcome of perinatal hypoxic-ischaemic encephalopathy at Chiang Mai University Hospital, Thailand: a 15-year retrospective study

BACKGROUND

The outcome of perinatal hypoxic-ischaemic encephalopathy (HIE) in middle-to-low-income countries varies between regions.

OBJECTIVES

To determine the mortality and morbidity, and factors influencing the deaths of infants with perinatal HIE.

METHODS

A retrospective study was conducted at Chiang Mai University Hospital, Thailand. Perinatal HIE infants of >35 weeks gestation, birthweight ≥2000 g and admitted during 2005-2019 were reviewed. Baseline Characteristics, clinical course and outcome at discharge were compared between the period before and after initiation of therapeutic hypothermia (TH). Risk of death in HIE infants who underwent TH was identified.

RESULTS

A total of 162 HIE infants were included. Compared to the period before TH initiation, the mortality rate was significantly decreased in the TH period. (27% vs. 12.8%, p=0.04) Among 100 HIE infants who underwent TH, the mortality rates was 14%(14/100), of whom 2.5% (2/76) and 50% (12/24) were in the moderate and severe HIE groups. Apgar score at 5 mins ≤1, severe HIE, seizures, hypoglycaemia, organ involvement ≥ five sites, ammonia ≥100 umol/L, lactate ≥14 mmol/L, and requirement for two or more inotropic drugs were risks of death. Multivariate analysis demonstrated that severe HIE (aOR 732.8, 95% CI 4.7-114643, p=0.01) and a need for two or more inotropic drugs (aOR 45.7, 95% CI 1.5-1040, p=0.029) were significant factors for mortality.

CONCLUSION

In the period of TH, perinatal HIE infants had decreased mortality. Severe HIE and a need for two or more inotropic drugs were associated with death in the infant with HIE who underwent TH.Abbreviations: AED: anti-epileptic drug; BW, birthweight; CI: confidence interval; CMU: Chiang Mai University; EEG: electro-encephalogram; GA: gestational age; HIE: hypoxic-ischaemic encephalopathy; IQR: interquartile range; NICU: neonatal intensive care unit; SD: standard deviation; TH: therapeutic hypothermia.