Olfactory Testing in Perinatal Asphyxia: Enhancing Risk Assessment

Summary

Neonatal asphyxia remains a leading cause of neurodevelopmental disabilities despite advancements in perinatal care. Hypoxic-ischemic encephalopathy (HIE), a severe outcome of asphyxia, impacts 1-3 infants per 1,000 live births annually in industrialized nations, causing long-term neurological impairments such as cognitive dysfunction, motor deficits, and sensory impairments. Early identification of at-risk newborns is critical to initiate timely interventions and improve outcomes.

Olfactory perception, crucial for newborns' adaptation to extrauterine life, involves odor identification and memory. Odor perception is known to be impaired in adults with neurological disorders and in animal models of brain injury. However, no clinical studies have assessed olfactory function in newborns with signs of asphyxia. Olfactory memory, which can be evaluated through habituation to repeated odors, may provide insights into early brain function.

This study aims to evaluate whether olfactory memory can serve as an early marker of neurodevelopmental outcomes in newborns with signs of asphyxia. By assessing physiological, behavioral, and neurological responses to olfactory stimuli, the study seeks to explore the differences between infants with mild asphyxia and those with moderate-to-severe asphyxia.

Conditions

• Mild Birth Asphyxia
• Moderate Birth Asphyxia

Interventions

DIAGNOSTIC_TEST

Olfactory Testing

Olfactory Test: Odor stimuli will be administered using a custom-designed olfactometer, developed by engineers specifically for this study. The olfactometer will release different odorants (maternal breast milk, vanilla essential oil, rose essential oil, and water as a control) in a controlled way. Each odor will be presented between 6 and 72 hours of life for 10 seconds (On), followed by a 50-second pause (Off) for a total of 15 cycles (On-Off). A new odor will be presented 5 minutes after the previous one. The first olfactory test will be conducted during the Video-EEG recording, and the second one will take place during the fMRI acquisition.

DIAGNOSTIC_TEST

Heart rate (HR), Heart Rate Variability (HRV), Respiratory Rate (RR), peripheral oxygen saturation (SpO2)

Simultaneously with the presentation of odors, heart rate (HR), heart rate variability (HRV), respiratory rate (RR), and peripheral oxygen saturation (SpO2) will be monitored and recorded. The onset of the odor will be recorded using a manual timer.

DIAGNOSTIC_TEST

Video-EEG

The infant's Video-EEG, as per guidelines following perinatal asphyxia, will be recorded for approximately 2 hours, including the period preceding odor administration (baseline).

DIAGNOSTIC_TEST

fMRI

Newborns will undergo an fMRI, as part of routine clinical practice, to identify any brain injury, its extent, and the structures involved. The use of a custom-built fMRI compatible olfactometer will facilitate these studies.

DIAGNOSTIC_TEST

Neurodevelopment assessment

Between 12 and 18 months, the infants will undergo neurodevelopmental follow-up, during which the Bayley III assessment will be administered to evaluate any potential neurocognitive deficits.

Sponsors & Collaborators

• Azienda Ospedaliero-Universitaria di Parma

  collaborator OTHER

• University of Parma

  lead OTHER

Principal Investigators

• Serafina Perrone, MD, PhD · Università di Parma

Eligibility

Min Age

6 Hours

Max Age

72 Hours

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2024-09-10

Primary Completion

2025-01-31

Completion

2026-09-10

Countries

• Italy

Study Locations