Updated Abdominal Compartment Society Consensus Definitions

Official title

Expert Consensus On Definitions And Management Of Intra-Abdominal Hypertension And Abdominal Compartment Syndrome

Overview

An international team of experts is working on a project called updated WSACS consensus definitions. The goals of this study are to: 1. To generate expert consensus on the definitions and classification of IAH and ACS. 2. To generate expert consensus on definitions regarding the pathophysiology of IAH and ACS. 3. To generate consensus on definitions regarding the methods of measurement of intra-abdominal pressure (IAP).

Detailed description

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are frequently encountered in critically ill or injured patients and remain associated with significant morbidity and mortality. IAH is defined as a sustained increase in intra-abdominal pressure (IAP) equal to or above 12 mmHg. It is diagnosed in approximately one-third of mixed medical and surgical intensive care unit (ICU) patients at admission and develops in about half during the first week of ICU stay. IAH has consistently been shown to be an independent predictor of adverse outcomes, including multi-organ dysfunction and death.

Following the original consensus definitions and subsequent guideline updates by the Abdominal Compartment Society (WSACS), the understanding and management of IAH and ACS have evolved substantially. While surgical etiologies such as trauma and ruptured abdominal aortic aneurysm were historically predominant, more recent data highlight that IAH and ACS frequently occur in medical ICU populations as well. Contributing factors include excessive fluid resuscitation, massive transfusion, venous congestion, and capillary leak, which can lead to secondary IAH and subsequent organ failure even in the absence of direct abdominal pathology.

Despite the availability of consensus guidelines and an improved understanding of the pathophysiology, it remains unclear whether prevention or active treatment of IAH directly improves patient outcomes. Furthermore, there is growing recognition of the need to refine the definitions, measurement techniques, and classification systems for IAH and ACS to reflect current clinical knowledge and practice across diverse healthcare settings.

The WSACS - The Abdominal Compartment Society - previously published comprehensive consensus definitions and recommendations in 2013. Since then, new research has provided additional insights into epidemiology, measurement technologies, classification systems, and the broader clinical implications of IAH and ACS. A recent global survey among healthcare professionals identified emerging areas of uncertainty and priority topics for definition updates.

In response, this study will conduct an international modified Delphi process to achieve expert consensus on updated definitions and clinical practice statements for IAH and ACS. The Delphi method will systematically collect and refine expert opinions over several iterative rounds, with the goal of reaching agreement on revised definitions, measurement approaches, pathophysiological frameworks, and classification criteria.

The outcome of this Delphi process will be a set of updated, evidence-informed, and globally endorsed definitions and recommendations for IAH, ACS, and the open abdomen. These consensus statements aim to harmonize terminology, support clinical decision-making, guide future research, and ultimately improve patient care. The target audience includes physicians, surgeons, intensivists, anesthesiologists, nurses, and policymakers involved in the management of critically ill or injured patients across both high- and low-to-middle-income countries.

Interventions

• Other Delphi study
  structured interview via online survey

Primary outcome measures

• Level of consensus on definitions of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) [Time frame: 3-6 months]

Secondary outcome measures (2)

• Level of consensus on pathophysiological concepts of IAH and ACS [Time frame: 3-6 months]
• Level of consensus on measurement methods for intra-abdominal pressure (IAP) [Time frame: 3-6 months]

Eligibility criteria

Inclusion Criteria: Panellists will be identified based on either of the following criteria At least 5 years of clinical experience as a staff member in Anesthesiology, Surgery or Intensive Care Medicine with involvement in care of patients with postoperative complications Author of at least one publication (observational studies or randomised controlled trials) on intra-abdominal hypertension or abdominal compartment syndrome. For patients and public involvement Individuals who have either personally experienced IAH or ACS following surgery or ICU within the last 5 years or, primary caregivers of such patients will be recruited as patient care representatives. Proficiency in English is required. To mitigate potential bias, patient care representatives mustn't maintain a professional or advisory relationship with the steering committee or panellists. Co-authors from previous WSACS survey published in 2024, former or current WSACS ambassadors, representative from WSES, ESAIC, ESICM.

Exclusion criteria

• None

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Observational model

Cohort

Study locations

Poland · 1 center

• Medical University of Lublin — Lublin

Publications

• Alhazzani W, Lewis K, Jaeschke R, Rochwerg B, Moller MH, Evans L, Wilson KC, Patel S, Coopersmith CM, Cecconi M, Guyatt G, Akl EA. Conflicts of interest disclosure forms and management in critical care clinical practice guidelines. Intensive Care Med. 2018 Oct;44(10):1691-1698. doi: 10.1007/s00134-018-5367-6. Epub 2018 Sep 27. PMID 30264380
• Traversy G, Barnieh L, Akl EA, Allan GM, Brouwers M, Ganache I, Grundy Q, Guyatt GH, Kelsall D, Leng G, Moore A, Persaud N, Schunemann HJ, Straus S, Thombs BD, Rodin R, Tonelli M. Managing conflicts of interest in the development of health guidelines. CMAJ. 2021 Jan 11;193(2):E49-E54. doi: 10.1503/cmaj.200651. No abstract available. PMID 33431547
• Schunemann HJ, Al-Ansary LA, Forland F, Kersten S, Komulainen J, Kopp IB, Macbeth F, Phillips SM, Robbins C, van der Wees P, Qaseem A; Board of Trustees of the Guidelines International Network. Guidelines International Network: Principles for Disclosure of Interests and Management of Conflicts in Guidelines. Ann Intern Med. 2015 Oct 6;163(7):548-53. doi: 10.7326/M14-1885. PMID 26436619
• Gattrell WT, Logullo P, van Zuuren EJ, Price A, Hughes EL, Blazey P, Winchester CC, Tovey D, Goldman K, Hungin AP, Harrison N. ACCORD (ACcurate COnsensus Reporting Document): A reporting guideline for consensus methods in biomedicine developed via a modified Delphi. PLoS Med. 2024 Jan 23;21(1):e1004326. doi: 10.1371/journal.pmed.1004326. eCollection 2024 Jan. PMID 38261576
• Nasa P, Jain R, Juneja D. Delphi methodology in healthcare research: How to decide its appropriateness. World J Methodol. 2021 Jul 20;11(4):116-129. doi: 10.5662/wjm.v11.i4.116. eCollection 2021 Jul 20. PMID 34322364
• Nasa P, Azoulay E, Khanna AK, Jain R, Gupta S, Javeri Y, Juneja D, Rangappa P, Sundararajan K, Alhazzani W, Antonelli M, Arabi YM, Bakker J, Brochard LJ, Deane AM, Du B, Einav S, Esteban A, Gajic O, Galvagno SM Jr, Guerin C, Jaber S, Khilnani GC, Koh Y, Lascarrou JB, Machado FR, Malbrain MLNG, Mancebo J, McCurdy MT, McGrath BA, Mehta S, Mekontso-Dessap A, Mer M, Nurok M, Park PK, Pelosi P, Peter J PMID 33726819
• Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, Shamseer L, Tetzlaff JM, Akl EA, Brennan SE, Chou R, Glanville J, Grimshaw JM, Hrobjartsson A, Lalu MM, Li T, Loder EW, Mayo-Wilson E, McDonald S, McGuinness LA, Stewart LA, Thomas J, Tricco AC, Welch VA, Whiting P, Moher D. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ. 2021 Mar 29;372:n71 PMID 33782057
• Nasa P, Wise RD, Smit M, Acosta S, D'Amours S, Beaubien-Souligny W, Bodnar Z, Coccolini F, Dangayach NS, Dabrowski W, Duchesne J, Ejike JC, Augustin G, De Keulenaer B, Kirkpatrick AW, Khanna AK, Kimball E, Koratala A, Lee RK, Leppaniemi A, Lerma EV, Marmolejo V, Meraz-Munoz A, Myatra SN, Niven D, Olvera C, Ordonez C, Petro C, Pereira BM, Ronco C, Regli A, Roberts DJ, Rola P, Rosen M, Shrestha GS, PMID 39609850

Identifiers

NCT: NCT07563842 · MUL2025WSACS001 · PROSPERO CRD420251167137

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗