Continuous Monitoring of Body Temperature in Neonates During Therapeutic Hypothermia

This is a prospective, single-center, observational pilot study designed to evaluate the feasibility, agreement, and safety of continuous non-invasive body temperature monitoring using the SteadyTemp® wireless adhesive thermometer in neonates undergoing therapeutic hypothermia. Therapeutic hypothermia is the standard treatment for term and near-term neonates with moderate to severe hypoxic-ischemic encephalopathy and requires precise continuous temperature monitoring to maintain a target core temperature of approximately 33.5°C. Currently, temperature control is achieved using an invasive rectal temperature probe connected to a servo-controlled cooling system. Although effective, rectal probes are associated with potential complications including tissue injury, perforation, infection, contraindications in selected clinical conditions, and increased handling of critically ill neonates.

SteadyTemp® is a wireless, skin-adherent temperature sensor that continuously records skin temperature and transfers data via near-field communication (NFC). While the device has previously demonstrated safe use in term neonates under normothermic conditions, its performance during therapeutic hypothermia has not yet been evaluated. Physiological differences between skin and core body temperature, particularly during hypothermia when peripheral perfusion is reduced, may influence measurement accuracy. This study is designed to generate preliminary clinical evidence regarding the ability of the device to track changes in body temperature during therapeutic hypothermia and to assess its suitability for future clinical use in this patient population.

Participants will undergo routine therapeutic hypothermia according to institutional clinical practice. Approximately 30 minutes before initiation of the rewarming phase, the SteadyTemp® adhesive thermometer will be applied to the right axillary region and remain in place throughout the rewarming period for approximately 7-10 hours. Routine rectal temperature monitoring will continue unchanged as part of standard clinical care. Temperature data from the SteadyTemp® sensor will be retrieved using NFC-compatible devices and documented in the case report form (CRF), while corresponding rectal temperature measurements will be extracted from the electronic medical record. Following removal of the adhesive patch, skin integrity will be assessed using the Neonatal Skin Condition Scale (NSCS) to evaluate local tolerability. No study-specific therapeutic interventions are performed beyond application of the adhesive thermometer.

As a pilot feasibility study, a convenience sample of ten participants will be enrolled. The sample size is intended to assess the technical feasibility of the monitoring protocol and to provide preliminary estimates of agreement between the non-invasive and invasive temperature measurement methods, which will inform sample size calculations for future confirmatory studies.

Data will be summarized using descriptive statistics. Continuous variables will be reported as means and standard deviations or medians and interquartile ranges, as appropriate, while categorical variables will be summarized as frequencies and percentages. Agreement between SteadyTemp® and rectal temperature measurements will be explored using Bland-Altman analysis, with estimation of the mean bias and preliminary 95% limits of agreement. Because of the exploratory nature and limited sample size, analyses will focus on descriptive rather than inferential statistics. If feasibility is demonstrated, the observed variability will be used to estimate the required sample size for subsequent validation studies.

Study data will be collected using paper-based case report forms and recorded in pseudonymized form using unique study identifiers. Personal data will be stored securely in accordance with applicable data protection regulations and archived for the legally required retention period. Double data entry verification will be performed to minimize transcription errors. Independent monitoring will be conducted according to a predefined monitoring plan to ensure protocol compliance, data quality, and protection of participant rights. Source data verification will be performed through comparison of CRF entries with original medical records, in accordance with ISO 14155, ICH-GCP (Good Clinical Practice), and institutional standard operating procedures. Study personnel will receive protocol-specific training before study initiation, and the use of the investigational device will be standardized through written standard operating procedures.

The Sponsor applies a risk-based quality management approach throughout the study. Study-specific risks will be continuously assessed and managed to ensure participant safety, data integrity, and regulatory compliance. Protocol deviations, adverse events, and device deficiencies will be documented and managed according to the clinical investigation plan and applicable Medical Device Regulation (EU) 2017/745 requirements. The study will be conducted in accordance with ISO 14155, ICH-GCP, the Declaration of Helsinki, and applicable national regulations governing clinical investigations of medical devices.

Inclusion criteria

• Neonates born at ≥36+0 weeks of gestation.
• Clinical indication for therapeutic hypothermia.
• Written informed consent obtained from the parents or legal guardians before study measurements are initiated.

Exclusion criteria

• Gestational age <36+0 weeks.
• No clinical indication for therapeutic hypothermia.
• Written informed consent not obtained from the parents or legal guardians.
• Congenital malformation.