Long-Term Effect of Noninvasive Ventilation on Diaphragm in Chronic Respiratory Failure

Diaphragm and Lung Transplantation

Mutual interactions between the diaphragm and lung transplantation (LTx) are known to exist. Before LTx, many factors can exert notable impact on the diaphragmatic function, such as the underlying respiratory disease, the comorbidities, and the chronic treatments of the patient. In the post-LTx setting, even the surgical procedure itself can cause a stressful trauma to the diaphragm, potentially leading to morphological and functional alterations. Conversely, the diaphragm can significantly influence various aspects of the LTx process, ranging from graft-to-chest cavity size matching to the long-term postoperative respiratory performance of the recipient. Despite this, there are still no standard criteria for evaluating, defining, and managing diaphragmatic dysfunction in the context of LTx to date. This deficiency hampers the accurate assessment of those factors which affect the diaphragm and its reciprocal influence on LTx outcomes. The objective of this narrative review is to delve into the complex role the diaphragm plays in the different stages of LTx and into the modifications of this muscle following surgery.

Acute COPD exacerbation treatment with noninvasive ventilation

The establishment of a guideline for long-term noninvasive ventilation treatment (LTH-NIV) of acute hypercapnic exacerbations of chronic obstructive pulmonary disease (AECOPD) requiring acute ventilation has proven elusive. Most studies thus far have shown no mortality benefit of long-term noninvasive ventilation treatment. Using retrospective analysis of the data of our patients (n = 143) recruited from 2012 to 2019, we aimed to compare patients discharged with and without long-term noninvasive ventilation. The follow-up results showed no significant difference (p = 0.233) between the groups [LTH-NIV (n = 83); non-NIV (n = 60)] regarding readmission due to clinical worsening. However, the first- and second-year survival rates were 82% and 72%, respectively, in the LTH-NIV group and significantly different (p = 0.023) from 67 and 55% in the non-NIV group. The statistical models showed a significant mortality risk for the non-NIV group, with a hazard ratio (HR) of 2.82 (1.31; 6.03). To the best of our knowledge, this is the first study to demonstrate the mortality benefit of long-term NIV therapy for patients with AECOPD under real-world conditions.

Chronic hypercapnic respiratory failure and non-invasive ventilation in people with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) should no longer be seen as a condition for which little can be done. Novel pharmacotherapeutic interventions, surgical and procedural advances, and respiratory assist devices have provided numerous ways to help patients with COPD and treatable traits. For nearly 30 years, non-invasive ventilation, the application of positive pressure through a mask interface placed outside of the airway, has been the cornerstone for treatment of acute hypercapnic respiratory failure due to COPD exacerbation. Clinical trials indicate that this intervention could benefit patients with COPD and chronic hypercapnic respiratory failure in a stable state. This narrative review aims to provide the necessary background for internists to consider this therapeutic option for their COPD patients. We discuss the mechanism of action and implementation, and provide a glimpse into the future of this promising intervention.