To discuss how measurement practices affect the bedside interpretation of the Gastrointestinal Dysfunction Score (GIDS), evaluated in a prospective multicentre study of 2,679 ICU patients.
Approach:
Study context: The letter considers the reported associations between GIDS and 28- and 90-day mortality, ICU-free days, and parenteral nutrition use.
Measurement context: It examines variable ascertainment of intra-abdominal pressure (IAP) and gastric residual volume (GRV), including classification of unmeasured components as normal.
Interpretation and validation: It discusses how measurement and treatment practices may shape scores and proposes reporting measurement circumstances in future validation.
Key Findings:
IAP was measured in 20.6% of patients and GRV in 41.1%; on the first study day, these measurements were absent in 86.6% and 69.0%, respectively.
Sensitivity analyses found that the mortality association persisted after excluding IAP, excluding both IAP and GRV, and comparing centres by IAP measurement practice.
These analyses do not establish that the same GIDS value represents the same clinical state when different components were measured.
The fully measured-score analysis included 311 patients for 28-day mortality and 309 for 90-day mortality; the 90-day estimate was imprecise and crossed the null (aHR 1.19, 95% CI 0.96–1.48).
GIDS components include factors influenced by clinical management, and the association with parenteral nutrition may partly reflect clinical decision-making.
Interpretation:
The letter characterizes GIDS as a pragmatic, outcome-associated composite and a framework for structured gastrointestinal observation. Its bedside meaning may partly depend on which components were measured and on monitoring and treatment practices.
Limitations:
IAP and GRV were measured inconsistently, and unmeasured components were classified as normal.
The fully measured-score analysis was small, and component availability did not require same-day measurement.
Whether GIDS-directed changes in nutrition or prokinetic therapy improve outcomes remains unestablished.
The relationship between score changes and reproducible changes in gastrointestinal function has not been established against an independent reference.
Conclusion:
The letter calls for future validation to report measurement circumstances, distinguish pragmatic from fully measured implementations, use prespecified methods for IAP and GRV ascertainment, and assess score changes against independent clinical or physiological references.
