Advertisement

Journal of Ultrasound

, Volume 21, Issue 2, pp 137–144 | Cite as

The learning curve of sonographic inferior vena cava evaluation by novice medical students: the Pavia experience

  • Santi Di Pietro
  • Francesco Falaschi
  • Alice Bruno
  • Tiziano Perrone
  • Valeria Musella
  • Stefano Perlini
Original Article

Abstract

Purpose

The sonographic evaluation of inferior vena cava diameters and its collapsibility—that is also defined as the caval index—has become a popular way to easily obtain a noninvasive estimate of central venous pressure. This is generally considered an easy sonographic task to perform, and according to the American College of Emergency Physicians (ACEP) Guidelines 25 repetitions of this procedure should be sufficient to reach proficiency. However, little is known about the learning process for this sonographic technique. Therefore, we designed this study to investigate the learning curve of inferior vena cava evaluation.

Methods

We enrolled a sample of ten ultrasound-naïve medical students who received a preliminary training provided by two Junior Emergency Medicine Residents. Following training, each student performed the sonographic task on 25 different patients who were hospitalized in the internal medicine ward. The students’ performance was compared with the results obtained by a consultant in internal medicine with extensive experience in point-of-care ultrasound, who repeated the procedure on the same patients (gold standard). In detail, we evaluated the time to complete the task, the quality of the obtained images, and the ability to visually estimate and measure the caval index.

Results

Although most students (9/10) reached the pre-defined level of competence, their overall performance was inferior to the one achieved by the gold standard, with little improvement over time. However, repetition was associated with progressive shortening of the time needed to achieve readable images.

Conclusions

Overall, these findings suggest that, although allowing to obtain a pre-defined competence, 25 repetitions are not enough to reach a good level of proficiency for this technique, that needs a longer training to be achieved.

Keywords

Inferior vena cava Caval index Learning curve Point of care ultrasound Ultrasound for undergraduates 

Sommario

Scopo

Lo studio ecografico della vena cava inferiore con la misurazione dei diametri e la valutazione della sua collassabilità agli atti respiratori, noto come caval index, si è diffuso come un semplice metodo per stimare in modo non invasivo la pressione venosa centrale. Generalmente questo task ecografico è considerato di semplice esecuzione, e, secondo linee guida dell’American College of Emergency Physicians (ACEP) 25 ripetizioni di questa procedura sarebbero sufficienti a raggiungere la proficiency. Tuttavia, la curva di apprendimento per questa tecnica è stata scarsamente studiata. Per questo abbiamo realizzato questo studio, al fine di analizzare il processo di apprendimento per lo studio ecografico della vena cava inferiore.

Metodi

Abbiamo arruolato un campione di 10 studenti di Medicina senza precedenti esperienze in ecografia. Gli studenti hanno dapprima ricevuto un training preliminare da parte di Specializzandi di Medicina d’Emergenza-Urgenza, e, successivamente, hanno eseguito il task ecografico su 25 pazienti ricoverati presso il reparto di Medicina Interna. Le performance degli studenti sono state confrontate con quelle di un medico strutturato di Medicina Interna con lunga esperienza in ecografia point-of-care, che ha ripetuto la procedura sugli stessi pazienti, fungendo quindi da gold-standard. I parametri analizzati sono stati il tempo per completare la procedura, la qualità delle immagini ottenute e la capacità di stimare visivamente e misurare il caval index.

Risultati

Anche se la maggior parte degli studenti (9/10) hanno raggiunto il livello predefinito di competenza, le loro performance sono state sommariamente inferiori rispetto a quelle del gold-standard, registrando un piccolo trend di miglioramento nei tempi medi per l’esecuzione del task ecografico.

Conclusioni

Questi risultati suggeriscono che, sebbene 25 ripetizioni consentano ad un soggetto inesperto di ottenere un livello pre-definito di competenza, non sembrano però essere sufficienti a raggiungere la proficiency necessaria per questa tecnica, che necessita di un training più lungo.

Notes

Compliance with ethical standards

Conflict of interest

We declare no conflict of interest or financial support for this article.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.

Supplementary material

40477_2018_292_MOESM1_ESM.pdf (89 kb)
Supplementary material 1 (PDF 89 kb)

References

  1. 1.
    Whitson MR, Mayo PH (2016) Ultrasonography in the emergency department. Crit Care 20:227CrossRefPubMedPubMedCentralGoogle Scholar
  2. 2.
    Cantisani V, Dietrich CF, Badea R et al (2016) EFSUMB statement on medical student education in ultrasound. Ultrasound Int Open 2:E2–E7CrossRefPubMedPubMedCentralGoogle Scholar
  3. 3.
    Baltarowich OH, Di Salvo DN, Scoutt LM et al (2014) National Ultrasound Curriculum for Medical Students. Ultrasound Quart 30(13Y):19Google Scholar
  4. 4.
    Ciozda W, Kedan I, Kehl DW et al (2016) The efficacy of sonographic measurement of inferior vena cava diameter as an estimate of central venous pressure. Cardiovasc Ultrasound 14:33CrossRefPubMedPubMedCentralGoogle Scholar
  5. 5.
    Orso D, Guglielmo N, Federici N et al (2016) Accuracy of the caval index and the expiratory diameter of the inferior vena cava for the diagnosis of dehydration in elderly. J Ultrasound 19(3):203–209CrossRefPubMedPubMedCentralGoogle Scholar
  6. 6.
    Prencipe M, Granata A, D’Amelio A et al (2016) Usefulness of US imaging in overhydrated nephropathic patients. J Ultrasound 19(1):7–13CrossRefPubMedGoogle Scholar
  7. 7.
    Perera P, Mailhot T, Riley D, Mandavia D (2010) T he RUSH exam: rapid Ultrasound in SHock in the evaluation of the critically ill. Emerg Med Clin North Am 28(1):29–56CrossRefPubMedGoogle Scholar
  8. 8.
    Riccardi A, Chiarbonello B, Minuto P et al (2013) Identification of the hydration state in emergency patients: correlation between caval index and BUN/creatinine ratio. Eur Rev Med Pharmacol Sci 17:1800–1803PubMedGoogle Scholar
  9. 9.
    Anderson KL, Jenq KY, Fields JM, Panebianco NL et al (2013) Diagnosing heart failure among acutely dyspneic patients with cardiac, inferior vena cava, and lung ultrasonography. Am J Emerg Med 31(8):1208–1214CrossRefPubMedGoogle Scholar
  10. 10.
    Via G, Tavazzi G, Price S (2016) Ten situations where inferior vena cava ultrasound may fail to accurately predict fluid responsiveness: a physiologically based point of view. Intensive Care Med 42(7):1164–1167CrossRefPubMedGoogle Scholar
  11. 11.
    Betancourt G et al (2016) Learning process and improvement of point-of-care ultrasound technique for subxiphoid visualization of the inferior vena cava. Crit Ultrasound J 8:4CrossRefGoogle Scholar
  12. 12.
    Ultrasound Guidelines: Emergency, Point-of-care, and Clinical Ultrasound Guidelines in Medicine. American College of Emergency Physicians, Policy Statement 2016Google Scholar
  13. 13.
  14. 14.
    Emergency Ultrasound Standard Reporting Guidelines. American College of Emergency Physicians 2011. (https://www.acep.org/Clinical—Practice-Management/Ultrasound)
  15. 15.
    Richard RA, Rao VV, Poston MB et al (2011) An integrated ultrasound curriculum (iUSC) for medical students: 4-year experience. Crit Ultrasound J 3(1):1–12CrossRefGoogle Scholar
  16. 16.
  17. 17.
    Dalen H, Gundersen GH, Skjetne K et al (2016) Feasibility and reliability of pocket-size ultrasound examinations of the pleural cavities and vena cava inferior performed by nurses in an outpatient heart failure clinic. Eur J Cardiovasc Nurs 14(4):286–293CrossRefGoogle Scholar
  18. 18.
    Evangelista A, Galuppo V, Méndez J et al (2016) Hand-held cardiac ultrasound screening performed by family doctors with remote expert support interpretation. Heart 102(5):376–382CrossRefPubMedGoogle Scholar
  19. 19.
    Kirkpatrick AW, Sirois M, Laupland KB et al (2004) Hand-held thoracic sonography for detecting post-traumatic pneumothoraces: the Extended Focused Assessment with Sonography for Trauma (EFAST). J Trauma 57(2):288–295CrossRefPubMedGoogle Scholar
  20. 20.
    Matthew Fields J, Lee Paul A, Jenq Katherine Y et al (2011) The interrater reliability of inferior vena cava ultrasound by bedside clinician sonographers in emergency department patients. Acad Emerg Med 18(1):98–101CrossRefPubMedGoogle Scholar
  21. 21.
    Panchal AR, Boulger C et al (2017) Inferior vena cava measurement with ultrasound: what is the best view and best mode? West J Emerg Med 18(3):496–501CrossRefPubMedPubMedCentralGoogle Scholar

Copyright information

© Società Italiana di Ultrasonologia in Medicina e Biologia (SIUMB) 2018

Authors and Affiliations

  1. 1.Clinica Medica 2, Department of Internal Medicine, Emergency Medicine Fellowship Program, Fondazione IRCCS Policlinico San MatteoUniversity of PaviaPaviaItaly
  2. 2.Clinica Medica 1, Department of Internal Medicine, Fondazione IRCCS Policlinico San MatteoUniversity of PaviaPaviaItaly
  3. 3.Clinical Epidemiology and Biometric Unit, Fondazione IRCCS Policlinico San MatteoUniversity of PaviaPaviaItaly
  4. 4.Clinica Medica 2, Department of Internal Medicine, IRCCS Policlinico San MatteoUniversity of PaviaPaviaItaly

Personalised recommendations