Outcome Measures to Evaluate Functional Recovery in Survivors of Respiratory Failure

Background

Respiratory failure is a life-threatening condition affecting millions of individuals in the United States annually. Survivors experience persistent functional impairments, decreased quality of life, and cognitive impairments. However, no established standard exists for measuring functional recovery among survivors of respiratory failure.

Research Question

What outcomes are being used to measure and characterize functional recovery among survivors of respiratory failure?

Study Design and Methods

In this scoping review, we developed a review protocol following International Prospective Register of Systematic Reviews (PROSPERO) guidelines. Two independent reviewers assessed titles and abstracts, followed by full-text review. Articles were included if study participants were aged 18 years or older, survived a hospitalization for acute respiratory failure, and received invasive mechanical ventilation as an intervention; identified function or functional recovery after respiratory failure as a study outcome; were peer-reviewed; and used any type of quantitative study design.

Results

We reviewed 5,873 abstracts and identified 56 eligible articles. Among these articles, 28 distinct measures were used to assess functional recovery among survivors, including both performance-based measures (n = 8) and self-reported and proxy-reported measures (n = 20). Before 2019, 12 of the 28 distinct outcome measures (43%) were used, whereas 25 distinct measures (89%) were used from 2019 through 2024. The 6-min walk test appeared most frequently (46%) across the studies, and only 34 of 56 studies measured outcomes ≥ 6 months after discharge or study enrollment.

Interpretation

Heterogeneity exists in how functional recovery is measured among survivors of respiratory failure, which highlights a need to establish a gold standard to ensure effective and consistent measurement.