Respiratory muscle dysfunction in acute and chronic respiratory failure: how to diagnose and how to treat?

Abstract

Assessing and treating respiratory muscle dysfunction is crucial for patients with both acute and chronic respiratory failure. Respiratory muscle dysfunction can contribute to the onset of respiratory failure and may also worsen due to interventions aimed at treatment. Evaluating respiratory muscle function is particularly valuable for diagnosing, phenotyping and assessing treatment efficacy in these patients. This review outlines established methods, such as measuring respiratory pressures, and explores novel techniques, including respiratory muscle neurophysiology assessments using electromyography and imaging with ultrasound.Additionally, we review various treatment strategies designed to support and alleviate the burden on overworked respiratory muscles or to enhance their capacity through training interventions. These strategies range from invasive and noninvasive mechanical ventilation approaches to specialised respiratory muscle training programmes. By summarising both established techniques and recent methodological advancements, this review aims to provide a comprehensive overview of the tools available in clinical practice for evaluating and treating respiratory muscle dysfunction. Our goal is to present a clear understanding of the current capabilities and limitations of these diagnostic and therapeutic approaches. Integrating advanced diagnostic methods and innovative treatment strategies should help improve patient management and outcomes. This comprehensive review serves as a resource for clinicians, equipping them with the necessary knowledge to effectively diagnose and treat respiratory muscle dysfunction in both acute and chronic respiratory failure scenarios.

FIGURE 1

Types of respiratory failure. The respiratory system can be considered as consisting of two parts: 1) the lung and 2) the pump, including the chest wall, respiratory muscles, and central/peripheral nervous system. Adapted from Roussos and Koutsoukou [1].

FIGURE 2

Diagnosis and treatment of diaphragm weakness. ABG: arterial blood gas; DTF: thickening fraction of the diaphragm; P_Imax: maximal inspiratory pressure; P_di,sniff: sniff transdiaphragmatic pressure; P_di,twitch: twitch transdiaphragmatic pressure; P_ga,sniff: sniff gastric pressure; SNIP: sniff nasal inspiratory pressure; VC: vital capacity.