Observer error in measuring shoulder-umbilical length in the newborn

  • Research type

    Research Study

  • Full title

    Using shoulder to umbilical length to estimate umbilical catheter insertion depth: does observer error impact accuracy?

  • IRAS ID

    201642

  • Contact name

    Helen Mactier

  • Contact email

    Helen.Mactier@ggc.scot.nhs.uk

  • Sponsor organisation

    NHS Greater Glasgow and Clyde

  • Clinicaltrials.gov Identifier

    16.YH.0042, Previous REC submission Ref

  • Duration of Study in the UK

    1 years, 0 months, 0 days

  • Research summary

    Umbilical venous and arterial catheters (UVCs and UACs respectively) are commonly inserted to provide central access in new born babies requiring intensive care. Correct placement depth is vital as incorrect placement can result in serious harm. Correct UVC/UAC placement depth is estimated based either a weight-based formula (weight based) or anatomical landmarks (length based) with no consensus on which is superior. A recent trial comparing these two formulae (weight vs length) found no significant difference in correct UVC placement but numbers were small. Neither method was consistently accurate. In our own unit, we notice a large variation between healthcare professionals when carrying out length based measurements which could be significantly affecting the estimated insertion depth. We aim to test and quantify this observation scientifically by watching healthcare practitioners carry out shoulder to umbilical measurements on babies (only some of whom will require UVC/UAC insertion) and recording the measurement they take. We will then assess the degree of variability both between users and within the same user (repeated measurements). The primary purpose of this non-invasive study is variability in measurement and so we will include all babies admitted to the two level 3 neonatal centres in Glasgow (Princess Royal Maternity (PRM) and Queen Elizabeth University Hospital (QUEH)), which will give us larger number appropriate to determine variability in measurement. We will also determine accuracy of measurement in determining final UVC/UAC position in those babies who need umbilical lines inserted for clinical reasons.
    If our study identifies significant observer variability when determining length based measurement, this would have clinical relevance in either demonstrating need to improve teaching of length measurement, or changing practice in favour of the more reproducible weight-based formula.

  • REC name

    South East Scotland REC 02

  • REC reference

    16/SS/0100

  • Date of REC Opinion

    23 May 2016

  • REC opinion

    Unfavourable Opinion