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Asynchrony index modified: An improved tool for estimating the quality of patient-ventilator interaction
Andres Mauricio Enriquez Popayan1,2, Longxiang Su3
1Departamento de Fisioterapia en Cuidados Intensivos SES Hospital Universitario de Caldas, Manizales, Colombia.
Background:
Patient-ventilator asynchronies are a common occurrence among patients receiving ventilatory support. Their clinical relevance has been explored for decades, most often through the Asynchrony Index, a simple and widely applicable tool. However, this index, it seems, may have some limitations and might not fully capture recent advances in understanding ventilatory asynchronies.
Methods:
Propose a novel index, the Asynchrony Index Modified (AIM), as an alternative conceptual approach intended to better reflect current understanding in this field. This index incorporates additional dimensions, including the type, intensity, and duration of asynchrony events, which could allow for a more nuanced estimation of the overall burden of patient-ventilator mismatch.
Results:
The AIM is conceived as a practical, non-invasive, and reproducible tool that can be applied at the bedside. The AIM could be quantified and may provide a complementary approach for exploring differences between distinct types of patient-ventilator asynchrony, with possible variation according to exposure time and asynchrony intensity.
Conclusion:
The AIM is consistent with the principles of precision mechanical ventilation and may represent a step forward in adapting assessment strategies to the evolving understanding of patient-ventilator asynchronies. However, it is important to consider that this proposal is based on a conceptual model, and further research may be necessary to evaluate the AIM, explore its clinical applicability, and establish clinically relevant cutoff values.
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