Bridging the gap: Enhancing synchrony in mechanical ventilation

Sorawit Ongsupankul, Christian John Capirig, Ehab G. Daoud

Abstract

Background

Mechanical ventilation is a life-saving intervention for patients with acute respiratory failure, yet ventilator dyssynchrony—misalignment between patient effort and ventilator support—remains a common challenge in intensive care units (ICUs). Dyssynchrony is associated with prolonged ventilation, diaphragm dysfunction, increased ICU and hospital stays, and higher mortality rates.

Objective

This review aims to provide an in-depth analysis of the physiological control of ventilation and its interaction with mechanical ventilators, emphasizing newer technologies and strategies to enhance patient-ventilator synchrony.

Methods

We examine key concepts in mechanical ventilation, including breath initiation (triggering), inspiratory flow patterns, and breath termination (cycling). We discuss the impact of ventilator dyssynchrony, including triggering and cycling abnormalities, and their physiological and clinical implications. Recent advances in ventilator technology and novel monitoring techniques are reviewed for their potential role in optimizing patient-ventilator interactions.

Results

Despite technological advancements, ventilator dyssynchrony remains prevalent, partly due to a lack of clinician education and variability in nomenclature. A recent international quiz assessing knowledge on dyssynchrony revealed an average score of 60%, highlighting the need for improved clinician training. The asynchrony index (AI) is a valuable metric for assessing dyssynchrony, and innovations such as adaptive support ventilation (ASV) and neurally adjusted ventilatory assist (NAVA) could improve dyssynchrony. Additionally, a novel approach utilizing esophageal pressure or electrical diaphragmatic activity (Edi) for triggering and cycling could enhance synchronization.

Conclusion

Optimizing patient-ventilator synchrony is crucial for improving outcomes in mechanically ventilated patients. Education, waveform analysis, and advanced ventilator technologies are key strategies for mitigating dyssynchrony. Future research should focus on novel signal-based control mechanisms to enhance ventilator responsiveness and align support with patient effort.

Keywords: Ventilator dyssynchrony, mechanical ventilation, patient-ventilator interaction, respiratory physiology, asynchrony index, esophageal pressure monitoring, AI

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