Hydrogen ion concentration of tear fluid in newborn infants

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H Dahl, C Dahl

    Acta Ophthalmologica
    |December 1, 1985
    PubMed

    Insights

    Newborn infant tear pH was measured, revealing a median value of 6.8. This easy and reliable method helps understand tear function in infants.

    Area of Science:

    • Ophthalmology
    • Neonatology
    • Physiology

    Background:

    • Tear pH is a crucial indicator of ocular surface health.
    • Understanding normal tear pH in newborns is essential for diagnosing potential ocular conditions.
    • Previous research on neonatal tear pH is limited.

    Purpose of the Study:

    • To determine the normal tear pH range in newborn infants.
    • To establish a reliable method for measuring tear pH in neonates.
    • To investigate factors influencing tear pH in newborns.

    Main Methods:

    • Tear pH was measured in 173 newborn infants using a microcombination glass pH probe.
    • The probe was immersed in the tear fluid within the closed lower conjunctival sac.
    • Data was collected and analyzed for median and mean pH values, along with interpercentile ranges.

    Main Results:

    • The median tear pH was 6.8, with a 95% interpercentile range of 6.2 to 7.2.
    • The mean tear pH was 6.74 +/- 0.26 (SD).
    • Tear pH was not significantly related to infant age (within 12 days), mode of delivery, or silver nitrate application.

    Conclusions:

    • The microcombination glass pH probe offers an easy and reliable method for assessing tear fluid pH in newborns.
    • This study provides valuable reference data for normal tear pH in neonates.
    • The findings may enhance the understanding of tear function in both normal and pathological neonatal ocular conditions.

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