Evaluation of the open abdomen classification system: a validity and reliability analysis.

Area of Science:

• Surgical innovation
• Trauma surgery
• Abdominal surgery

Background:

• Accurate classification of open abdomen (OA) status is crucial for clinical research and optimizing OA management.
• This study assesses the validity and reliability of the World Society of the Abdominal Compartment Syndrome's 2013 OA classification system.

Purpose of the Study:

• To evaluate the validity and reliability of a proposed open abdomen classification system.
• To determine if OA grades correlate with patient outcomes such as fascial closure rates and mortality.

Main Methods:

• Prospective analysis of 111 open abdomen patients treated with vacuum-assisted wound closure and mesh-mediated fascial traction (VAWCM).
• Validity assessed by comparing OA grades with fascial closure and mortality rates.
• Reliability tested by three external raters grading operative reports twice, with inter-rater and test-retest comparisons.

Main Results:

• In-hospital mortality was 30%; delayed primary fascial closure rate was 89%.
• More complex OA grades, deteriorating grades, enteric leaks, and enteroatmospheric fistulas correlated with worse outcomes.
• A floor effect was noted, with 20% of patients receiving the lowest grade, impacting validity.

Conclusions:

• Higher open abdomen grades are linked to poorer clinical outcomes.
• The effectiveness of VAWCM led to a floor effect, reducing the classification's validity.
• The classification demonstrated good to very good inter-rater and test-retest reliability.