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Assessment and Evaluation of the High Risk Neonate: The NICU Network Neurobehavioral Scale
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Assessment and Evaluation of the High Risk Neonate: The NICU Network Neurobehavioral Scale

Published on: August 25, 2014

Olfactory reflexes in the newborn infant

H B Sarnat

    The Journal of Pediatrics
    |April 1, 1978
    PubMed

    Insights

    Peppermint odor elicits olfactory reflexes in infants, including premature babies. These reflexes can help identify brain abnormalities in newborns.

    Area of Science:

    • Neonatal physiology
    • Neurodevelopmental pediatrics
    • Olfactory system research

    Background:

    • Infant responses to odors are not fully understood.
    • The olfactory system's development and function in neonates require further investigation.
    • Clinical significance of olfactory reflexes in infant assessment is an area of interest.

    Purpose of the Study:

    • To investigate clinical responses to peppermint odor in healthy and compromised infants.
    • To determine the gestational age at which olfactory reflexes mature.
    • To explore the utility of olfactory reflexes in diagnosing neurological conditions.

    Main Methods:

    • Administered peppermint odor to healthy term and preterm infants during active sleep.
    • Tested asphyxiated term infants and infants with holoprosencephaly.
    • Observed and recorded infant responses, including sucking, arousal-withdrawal, and Moro reflex.
    • Assessed olfactory reflex elicitation based on gestational age.

    Main Results:

    • Healthy infants (100) and some premature infants (from 28 weeks gestation) showed olfactory reflexes to peppermint odor.
    • Responses included sucking initiation and arousal-withdrawal.
    • Habituation occurred within 2-3 trials.
    • Asphyxiated infants showed limited Moro response; loss of olfactory reflexes correlated with suppressed brainstem reflexes.

    Conclusions:

    • Olfactory reflexes are present in infants from 28 weeks gestation.
    • Olfactory reflex assessment can aid in excluding cerebral malformations like agenesis of the olfactory bulbs.
    • The findings highlight the importance of olfactory reflexes in neonatal neurological assessment.

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