Reverse Triggering Dyssynchrony 24 h after Initiation of Mechanical Ventilation

Area of Science:

• Critical Care Medicine
• Respiratory Physiology
• Medical Technology

Background:

• Reverse triggering is a diaphragm contraction caused by ventilator insufflation in sedated, mechanically ventilated patients.
• The incidence and prevalence of reverse triggering in critically ill patients are not well-established.
• Understanding reverse triggering is crucial for optimizing mechanical ventilation strategies.

Purpose of the Study:

• To determine the incidence of reverse triggering in critically ill patients receiving controlled mechanical ventilation.
• To develop and validate a method for automatic detection of reverse triggering using diaphragmatic electrical activity.
• To assess the association between reverse triggering and clinical outcomes such as mode transition or extubation.

Main Methods:

• Ancillary study involving continuous monitoring of diaphragmatic electrical activity via catheter in sedated, mechanically ventilated patients.
• Development and validation of a software algorithm for automatic detection of reverse triggering.
• Analysis of 1-hour recordings from 39 recently intubated patients under assist-control ventilation 24 hours post-intubation.
• Comparison of patient demographics, sedation levels, ventilation settings, and clinical outcomes based on reverse triggering rates.

Main Results:

• The developed software demonstrated high predictive values for reverse triggering detection (positive: 0.74, negative: 0.97).
• Using a 1 μV threshold, the median reverse triggering rate was 8%, with 44% of patients exhibiting ≥10% reverse triggering.
• Using a 3 μV threshold, 26% of patients exhibited ≥10% reverse triggering.
• Higher rates of reverse triggering were associated with a greater likelihood of progressing to assisted ventilation or extubation within 24 hours (68% vs. 35%).

Conclusions:

• Reverse triggering is highly prevalent in critically ill patients 24 hours after intubation under assist-control ventilation.
• The findings suggest reverse triggering occurs during the transition from deep sedation to patient-ventilator interaction.
• Diaphragmatic electrical activity monitoring provides a reliable method for detecting reverse triggering.