Respiratory Effort Monitoring: a Novel, Bedside, Non- invasive, Real-time Method

Background Mechanical ventilation is essential for treating respiratory failure. However, ventilator over-assistance can lead to ventilator-induced diaphragm dysfunction (VIDD), and inadequate assistance can necessitate excessive effort, which can be detrimental to lung mechanics and damage diaphragm function. Current monitoring methods face clinical implementation challenges due to invasiveness and complexity. This study introduces and validates a novel non-invasive real-time respiratory muscle pressure (N-Pmus) monitoring method. Methods 1) The bench study involved developing a non-invasive, real-time respiratory muscle pressure monitoring algorithm (N-Pmus) based on respiratory mechanics equations and validated against an ASL5000 lung simulator across 270 clinical scenarios. 2) A clinical validation was conducted as a self-randomized controlled study(n = 23) comparing N-Pmus with the Pmus derived from simultaneously monitored esophageal pressure (Pes-Pmus) to assess correlation and agreement. The association between N-Pmus and the established Pmus benchmarks was analyzed using linear mixed-effects models. Bias and agreement were evaluated through Bland–Altman analysis for repeated measures. Results 1) The bench study demonstrated that N-Pmus correlated well with ASL5000-Pmus, with marginal R²=0.993 and conditional R²=0.997. The bias was − 0.23 cmH₂O, with limits of agreement ranging from − 1.51 to 1.04 cmH₂O. 2) The clinical validation revealed strong N-Pmus/Pes-Pmus agreement with marginal R²=0.97 and conditional R²=0.971. The bias was − 0.2 cmH₂O, with limits of agreement ranging from − 2.22 to 1.83 cmH₂O. Conclusions N-Pmus, a novel, non-invasive real-time monitoring method, demonstrates a strong correlation and agreement with the established Pmus benchmarks (ASL5000-Pmus or Pes-Pmus), offering an effective means of assessing respiratory effort in mechanically ventilated patients. Clinical trial retrospectively registered with www.chictr.org.cn . Registration number : ChiCTR2300076940, registered 24 October 2023.