EXpert consensus On Diaphragm UltraSonography in the critically ill (EXODUS): a Delphi consensus statement on the measurement of diaphragm ultrasound-derived parameters in a critical care setting

Mark E. Haaksma*, Jasper M. Smit, Alain Boussuges, Alexandre Demoule, Martin Dres, Giovanni Ferrari, Paolo Formenti, Ewan C. Goligher, Leo Heunks, Endry H.T. Lim, Lidwine B. Mokkink, Eleni Soilemezi, Zhonghua Shi, Michele Umbrello, Luigi Vetrugno, Emmanuel Vivier, Lei Xu, Massimo Zambon, Pieter R. Tuinman

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

47 Citations (Scopus)
11 Downloads (Pure)


Background: Diaphragm ultrasonography is rapidly evolving in both critical care and research. Nevertheless, methodologically robust guidelines on its methodology and acquiring expertise do not, or only partially, exist. Therefore, we set out to provide consensus-based statements towards a universal measurement protocol for diaphragm ultrasonography and establish key areas for research. Methods: To formulate a robust expert consensus statement, between November 2020 and May 2021, a two-round, anonymous and online survey-based Delphi study among experts in the field was performed. Based on the literature review, the following domains were chosen: “Anatomy and physiology”, “Transducer Settings”, “Ventilator Impact”, “Learning and expertise”, “Daily practice” and “Future directions”. Agreement of ≥ 68% (≥ 10 panelists) was needed to reach consensus on a question. Results: Of 18 panelists invited, 14 agreed to participate in the survey. After two rounds, the survey included 117 questions of which 42 questions were designed to collect arguments and opinions and 75 questions aimed at reaching consensus. Of these, 46 (61%) consensus was reached. In both rounds, the response rate was 100%. Among others, there was agreement on measuring thickness between the pleura and peritoneum, using > 10% decrease in thickness as cut-off for atrophy and using 40 examinations as minimum training to use diaphragm ultrasonography in clinical practice. In addition, key areas for research were established. Conclusion: This expert consensus statement presents the first set of consensus-based statements on diaphragm ultrasonography methodology. They serve to ensure high-quality and homogenous measurements in daily clinical practice and in research. In addition, important gaps in current knowledge and thereby key areas for research are established. Trial registration The study was pre-registered on the Open Science Framework with registration digital object identifier

Original languageEnglish
Article number99
JournalCritical Care
Issue number1
Publication statusPublished - 8 Apr 2022

Bibliographical note

Funding Information:
We thank Heder de Vries, Annemijn Jonkman, Myrte Wennen and Micah Heldeweg for evaluating the pilot questionnaire for comprehensiveness and completeness. List of panelists in alphabetical order : Alain Boussuges (France), Alexandre Demoule (France), Martin Dres (France), Giovanni Ferrari (Italy), Paolo Formenti (Italy), Ewan C. Goligher (Canada), Leo Heunks (The Netherlands), Eleni Soilemezi (Greece), Zhonghua Shi (China), Michele Umbrello (Italy), Luigi Vetrugno (Italy), Emmanuel Vivier (France), Lei Xu (China) and Massimo Zambon (Italy).

Funding Information:
Dr. Demoule reports personal fees from Medtronic, grants, personal fees and non-financial support from Philips, personal fees from Baxter, personal fees from Hamilton, personal fees and non-financial support from Fisher & Paykel, grants from the French Ministry of Health, personal fees from Getinge, grants and personal fees from Respinor, grants and non-financial support from Lungpacer. Dr. Dres reports personal fees and travel expenses from Lungpacer Medical Inc., personal fees and congress registration from Dräger, research contract from Bioserenity and grant from the French Ministry of Health. Dr Heunks reports consultancy from Liberate Medical, research grant from Liberate medical paid to institution, and speakers fee from Fisher & Paykel and from Getinge. Drs. Boussuges, Ferrari, Formenti, Goligher, Haaksma, Lim, Mokkink, Shi, Smit, Soilemezi Tuinman, Umbrello, Vetrugno, Vivier, Xu and Zambon report no conflicts of interest.

Publisher Copyright:
© 2022, The Author(s).


Dive into the research topics of 'EXpert consensus On Diaphragm UltraSonography in the critically ill (EXODUS): a Delphi consensus statement on the measurement of diaphragm ultrasound-derived parameters in a critical care setting'. Together they form a unique fingerprint.

Cite this