ArticleCritical care (London, England)2021
Flow Index: a novel, non-invasive, continuous, quantitative method to evaluate patient inspiratory effort during pressure support ventilation.
Article in Critical care (London, England), 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers.
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Who cites it
15 citing papers in PubMed, 39 citations in OpenAlex.
- Flow Index Trajectories During Spontaneous Breathing Trials Are Associated With Extubation Failure: A Latent Class Trajectory Modeling Study.Clinical and translational science · 2026Article
- Electrical impedance tomography-derived flow index during spontaneous breathing trial stratifies the risk of reintubation within 48 h after extubation.Critical care (London, England) · 2026Observational
- Development of a deep-learning model for classification of intensivists' extubation decisions using ventilator graphic monitor images: a prospective observational study.Journal of intensive care · 2026Article
- Mechanical ventilation in ARDS: navigating the fine line with real-time monitoring.Critical care (London, England) · 2026Review
- The invasive and non-invasive monitoring of inspiratory effort and drive during assisted mechanical ventilation.Annals of intensive care · 2026Review
- Assessing inspiratory drive and effort in critically ill patients at the bedside.Critical care (London, England) · 2025Review
- Respiratory effort monitoring: a novel, bedside, non-invasive, real-time method.Critical care (London, England) · 2025Observational
- A feedback-driven ventilation model for assessing airway secretions in mechanically ventilated patients.Frontiers in physiology · 2025Article
- Assessing agreement among non-invasive indicators for inspiratory effort during pressure support ventilation.Frontiers in medicine · 2025Article
- Advanced Respiratory Monitoring during Extracorporeal Membrane Oxygenation.Journal of clinical medicine · 2024Review
- Use of pressure muscle index to predict the contribution of patient's inspiratory effort during pressure support ventilation: a prospective physiological study.Frontiers in medicine · 2024Article
- Neural Network-Enabled Identification of Weak Inspiratory Efforts during Pressure Support Ventilation Using Ventilator Waveforms.Journal of personalized medicine · 2023Article
- Validation of the flow index to detect low inspiratory effort during pressure support ventilation.Annals of intensive care · 2022Article
- Paced breathing and respiratory movement responses evoked by bidirectional constant current stimulation in anesthetized rabbits.Frontiers in bioengineering and biotechnology · 2022Article
- Flow Index accurately identifies breaths with low or high inspiratory effort during pressure support ventilation.Critical care (London, England) · 2021Article
Corrections and comments
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Authors and funding
14 authors at 7 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe evaluation of patient effort is pivotal during pressure support ventilation, but a non-invasive, continuous, quantitative method to assess patient inspiratory effort is still lacking. We hypothesized that the concavity of the inspiratory flow-time waveform could be useful to estimate patient's inspiratory effort. The purpose of this study was to assess whether the shape of the inspiratory flow, as quantified by a numeric indicator, could be associated with inspiratory effort during pressure support ventilation.
methodsTwenty-four patients in pressure support ventilation were enrolled. A mathematical relationship describing the decay pattern of the inspiratory flow profile was developed. The parameter hypothesized to estimate effort was named Flow Index. Esophageal pressure, airway pressure, airflow, and volume waveforms were recorded at three support levels (maximum, minimum and baseline). The association between Flow Index and reference measures of patient effort (pressure time product and pressure generated by respiratory muscles) was evaluated using linear mixed effects models adjusted for tidal volume, respiratory rate and respiratory rate/tidal volume.
resultsFlow Index was different at the three pressure support levels and all group comparisons were statistically significant. In all tested models, Flow Index was independently associated with patient effort (p < 0.001). Flow Index prediction of inspiratory effort agreed with esophageal pressure-based methods.
conclusionsFlow Index is associated with patient inspiratory effort during pressure support ventilation, and may provide potentially useful information for setting inspiratory support and monitoring patient-ventilator interactions.
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