Neonatal hypoxic-ischemic encephalopathy online registry in Shenzhen: protocol for a multicentre, prospective, open, observational cohort study.

The study will recruit 200 neonates with HIE from 10 hospitals in Shenzhen, China, over a defined enrollment period.

• Recruitment is planned between January 2025 and December 2028.
• Participating institutions number 10 hospitals in Shenzhen, China.
• The target sample size is 200 neonates with HIE.
• This is a multicentre, prospective, open, observational cohort study design.

Clinical data will be collected during hospitalisation with supplemental referral information obtained from birth hospitals via an online, specialised HIE database.

• An online specialised HIE database will be used for data collection.
• Supplemental referral information will be obtained from birth hospitals.
• Data collection includes HIE severity, survival status, and incidence of serious complications.
• Serious complications tracked include arrhythmias, pulmonary haemorrhage, neonatal acute respiratory distress syndrome, persistent pulmonary hypertension of the newborn, and disseminated intravascular coagulation.

Longitudinal follow-up is scheduled at 18, 24, and 36 months post-enrollment to assess neurodevelopmental outcomes.

• Follow-up timepoints are 18, 24, and 36 months.
• Assessments include physical developmental scales and video-electroencephalogram (VEEG) recordings.
• The Chinese version of the Bayley Infant and Toddler Developmental Scale, Fourth Edition will be administered.
• Cranial MRI will be performed at 18 months.
• Primary objectives include determining survival status, tracking loss-to-follow-up rates, and evaluating neurodevelopmental outcomes at 3 years.

The study addresses a gap in systematic data on HIE aetiology and prognosis, particularly in China, where such registry data are lacking.

• HIE is described as 'a leading cause of neurological disability in neonates.'
• Therapeutic hypothermia is the current management approach for HIE.
• The authors state that 'systematic data on its aetiology and prognosis are lacking, particularly in China.'
• The ultimate goal is described as 'enhancing our understanding of HIE risk factors, hypothermia therapy and prognosis to reduce HIE-related morbidity and disability.'

The study protocol received ethical approval from the Medical Ethics Committee of Shenzhen Children's Hospital and was registered in a clinical trials registry.

• Ethics approval number is 2024096, granted by the Medical Ethics Committee of Shenzhen Children's Hospital.
• The study is registered under ChiCTR2400094994.
• Findings will be disseminated through national academic conference presentations and peer-reviewed paediatric journal publications.