Trainee anaesthetist diagnosis of intraneural injection. A study comparing B-Mode ultrasound with the fusion of B-Mode and elastography in the soft embalmed Thiel cadaver model

S. Munimara, K. Zeally, A. Schwab, M. Columb, G. A. Corner, R. Eisma, G. A. McLeod (Lead / Corresponding author)

    Research output: Contribution to journalArticle

    4 Citations (Scopus)
    106 Downloads (Pure)

    Abstract

    Background: The incidence of intraneural injection during trainee anaesthetist ultrasound guided nerve block varies between 16% in experts and up to 35% in trainees. We hypothesised that elastography, an ultrasound-based technology that presents colour images of tissue strain had the potential to improve trainee diagnosis of intraneural injection during UGRA when integrated with B-Mode ultrasound onto a single image. Methods: We recorded 40 median nerve blocks randomly allocated to 0.25ml, 0.5ml, 1ml volumes to 5 sites on both arms of two soft embalmed cadavers using a dedicated B-Mode ultrasound and elastography transducer. We wrote software to fuse elastogram and B-Mode videos then asked 20 trainee anaesthetists whether injection was intraneural or extraneural when visualising B-Mode videos, adjacent B-Mode and elastogram videos, fusion elastography videos or repeated B-Mode ultrasound videos. Results: Fusion elastography improved the diagnosis of intraneural injection compared to B-Mode ultrasound, Diagnostic Odds Ratio (DOR) (95%CI) 21.7 (14.5 - 33.3) versus DOR 7.4 (5.2 – 10.6), P<0.001. Compared to extraneural injection, intraneural injection was identified on fusion elastography as a distinct, brighter translucent image, geometric ratio 0.33 (95%CI: 0.16 – 0.49) P<0.001. Fusion elastography was associated with greater trainee diagnostic confidence, OR (95%CI) 1.89 (1.69 – 2.11), P<0.001, and an improvement in reliability, Kappa 0.60 (0.55 - 0.66). Conclusions: Fusion elastography improved the accuracy, reliability and confidence of trainee anaesthetist diagnosis of intraneural injection.
    Original languageEnglish
    Pages (from-to)792-800
    Number of pages9
    JournalBritish Journal of Anaesthesia
    Volume117
    Issue number6
    DOIs
    Publication statusPublished - Dec 2016

    Fingerprint

    Elasticity Imaging Techniques
    Cadaver
    Injections
    Nerve Block
    Odds Ratio
    Anesthetists
    Median Nerve
    Transducers
    Ultrasonography
    Software
    Color
    Technology

    Keywords

    • Elastography
    • Regional anaesthesia
    • Ultrasonography

    Cite this

    @article{f44949263b8440e48af5e91eb6239bc3,
    title = "Trainee anaesthetist diagnosis of intraneural injection. A study comparing B-Mode ultrasound with the fusion of B-Mode and elastography in the soft embalmed Thiel cadaver model",
    abstract = "Background: The incidence of intraneural injection during trainee anaesthetist ultrasound guided nerve block varies between 16{\%} in experts and up to 35{\%} in trainees. We hypothesised that elastography, an ultrasound-based technology that presents colour images of tissue strain had the potential to improve trainee diagnosis of intraneural injection during UGRA when integrated with B-Mode ultrasound onto a single image. Methods: We recorded 40 median nerve blocks randomly allocated to 0.25ml, 0.5ml, 1ml volumes to 5 sites on both arms of two soft embalmed cadavers using a dedicated B-Mode ultrasound and elastography transducer. We wrote software to fuse elastogram and B-Mode videos then asked 20 trainee anaesthetists whether injection was intraneural or extraneural when visualising B-Mode videos, adjacent B-Mode and elastogram videos, fusion elastography videos or repeated B-Mode ultrasound videos. Results: Fusion elastography improved the diagnosis of intraneural injection compared to B-Mode ultrasound, Diagnostic Odds Ratio (DOR) (95{\%}CI) 21.7 (14.5 - 33.3) versus DOR 7.4 (5.2 – 10.6), P<0.001. Compared to extraneural injection, intraneural injection was identified on fusion elastography as a distinct, brighter translucent image, geometric ratio 0.33 (95{\%}CI: 0.16 – 0.49) P<0.001. Fusion elastography was associated with greater trainee diagnostic confidence, OR (95{\%}CI) 1.89 (1.69 – 2.11), P<0.001, and an improvement in reliability, Kappa 0.60 (0.55 - 0.66). Conclusions: Fusion elastography improved the accuracy, reliability and confidence of trainee anaesthetist diagnosis of intraneural injection.",
    keywords = "Elastography, Regional anaesthesia, Ultrasonography",
    author = "S. Munimara and K. Zeally and A. Schwab and M. Columb and Corner, {G. A.} and R. Eisma and McLeod, {G. A.}",
    note = "no funding",
    year = "2016",
    month = "12",
    doi = "10.1093/bja/aew337",
    language = "English",
    volume = "117",
    pages = "792--800",
    journal = "British Journal of Anaesthesia",
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    Trainee anaesthetist diagnosis of intraneural injection. A study comparing B-Mode ultrasound with the fusion of B-Mode and elastography in the soft embalmed Thiel cadaver model. / Munimara, S.; Zeally, K. ; Schwab, A.; Columb, M.; Corner, G. A.; Eisma, R.; McLeod, G. A. (Lead / Corresponding author).

    In: British Journal of Anaesthesia, Vol. 117, No. 6, 12.2016, p. 792-800.

    Research output: Contribution to journalArticle

    TY - JOUR

    T1 - Trainee anaesthetist diagnosis of intraneural injection. A study comparing B-Mode ultrasound with the fusion of B-Mode and elastography in the soft embalmed Thiel cadaver model

    AU - Munimara, S.

    AU - Zeally, K.

    AU - Schwab, A.

    AU - Columb, M.

    AU - Corner, G. A.

    AU - Eisma, R.

    AU - McLeod, G. A.

    N1 - no funding

    PY - 2016/12

    Y1 - 2016/12

    N2 - Background: The incidence of intraneural injection during trainee anaesthetist ultrasound guided nerve block varies between 16% in experts and up to 35% in trainees. We hypothesised that elastography, an ultrasound-based technology that presents colour images of tissue strain had the potential to improve trainee diagnosis of intraneural injection during UGRA when integrated with B-Mode ultrasound onto a single image. Methods: We recorded 40 median nerve blocks randomly allocated to 0.25ml, 0.5ml, 1ml volumes to 5 sites on both arms of two soft embalmed cadavers using a dedicated B-Mode ultrasound and elastography transducer. We wrote software to fuse elastogram and B-Mode videos then asked 20 trainee anaesthetists whether injection was intraneural or extraneural when visualising B-Mode videos, adjacent B-Mode and elastogram videos, fusion elastography videos or repeated B-Mode ultrasound videos. Results: Fusion elastography improved the diagnosis of intraneural injection compared to B-Mode ultrasound, Diagnostic Odds Ratio (DOR) (95%CI) 21.7 (14.5 - 33.3) versus DOR 7.4 (5.2 – 10.6), P<0.001. Compared to extraneural injection, intraneural injection was identified on fusion elastography as a distinct, brighter translucent image, geometric ratio 0.33 (95%CI: 0.16 – 0.49) P<0.001. Fusion elastography was associated with greater trainee diagnostic confidence, OR (95%CI) 1.89 (1.69 – 2.11), P<0.001, and an improvement in reliability, Kappa 0.60 (0.55 - 0.66). Conclusions: Fusion elastography improved the accuracy, reliability and confidence of trainee anaesthetist diagnosis of intraneural injection.

    AB - Background: The incidence of intraneural injection during trainee anaesthetist ultrasound guided nerve block varies between 16% in experts and up to 35% in trainees. We hypothesised that elastography, an ultrasound-based technology that presents colour images of tissue strain had the potential to improve trainee diagnosis of intraneural injection during UGRA when integrated with B-Mode ultrasound onto a single image. Methods: We recorded 40 median nerve blocks randomly allocated to 0.25ml, 0.5ml, 1ml volumes to 5 sites on both arms of two soft embalmed cadavers using a dedicated B-Mode ultrasound and elastography transducer. We wrote software to fuse elastogram and B-Mode videos then asked 20 trainee anaesthetists whether injection was intraneural or extraneural when visualising B-Mode videos, adjacent B-Mode and elastogram videos, fusion elastography videos or repeated B-Mode ultrasound videos. Results: Fusion elastography improved the diagnosis of intraneural injection compared to B-Mode ultrasound, Diagnostic Odds Ratio (DOR) (95%CI) 21.7 (14.5 - 33.3) versus DOR 7.4 (5.2 – 10.6), P<0.001. Compared to extraneural injection, intraneural injection was identified on fusion elastography as a distinct, brighter translucent image, geometric ratio 0.33 (95%CI: 0.16 – 0.49) P<0.001. Fusion elastography was associated with greater trainee diagnostic confidence, OR (95%CI) 1.89 (1.69 – 2.11), P<0.001, and an improvement in reliability, Kappa 0.60 (0.55 - 0.66). Conclusions: Fusion elastography improved the accuracy, reliability and confidence of trainee anaesthetist diagnosis of intraneural injection.

    KW - Elastography

    KW - Regional anaesthesia

    KW - Ultrasonography

    U2 - 10.1093/bja/aew337

    DO - 10.1093/bja/aew337

    M3 - Article

    VL - 117

    SP - 792

    EP - 800

    JO - British Journal of Anaesthesia

    JF - British Journal of Anaesthesia

    SN - 0007-0912

    IS - 6

    ER -