Inspiratory Muscle Dysfunction Mediates and Predicts a Disease Continuum of Hypercapnic Failure in Chronic Obstructive Pulmonary Disease.

Introduction: Advanced chronic obstructive pulmonary disease (COPD) is associated with chronic hypercapnic failure. The present work aimed to comprehensively investigate inspiratory muscle function as a potential key determinant of hypercapnic respiratory failure in patients with COPD.

Methods: Prospective patient recruitment encompassed 61 stable subjects with COPD across different stages of respiratory failure, ranging from normocapnia to isolated nighttime hypercapnia and daytime hypercapnia.

Interaction of panic and episodic breathlessness among patients with life-limiting diseases: a cross-sectional study.

Background: Episodic breathlessness is often accompanied by panic. A vicious cycle of breathlessness-panic-breathlessness leads to emergencies with severe breathlessness and/or fear of dying. However, the interaction between episodic breathlessness and panic is poorly understood.

Decannulation/Weaning Potential and Success in Home Intensive Care.

Background: The number of patients receiving home long-term ventilation has risen considerably in recent decades owing to medical advancements. Experts believe that the potential for ventilator weaning or tracheostoma removal is currently insufficiently exploited.

Objective: The objective of this study was to investigate the characteristics, prognosis, and decannulation/weaning potential of patients under home intensive care.

Initial Proportion and Dynamic of B.1.1.7 SARS-CoV-2 in a Large City in the West of Germany.

Rationale: Several mutational variants of SARS-CoV-2 have been identified in the past months with increasing prevalence worldwide. Some variants, such as B.1.

The experience of episodic breathlessness from the perspective of informal caregivers: a qualitative interview study.

Background: Episodic breathlessness is a common form of chronic breathlessness that is highly distressing for patients with diseases such as chronic obstructive pulmonary disease (COPD) and lung cancer in advanced stages. Little is known about the experiences of informal caregivers who care for patients with episodic breathlessness. The present study aims to explore and describe the experiences and coping strategies of informal caregivers who deal with this challenging condition.

Randomized Clinical Study of Temporary Transvenous Phrenic Nerve Stimulation in Difficult-to-Wean Patients.

Diaphragm dysfunction is frequently observed in critically ill patients with difficult weaning from mechanical ventilation. To evaluate the effects of temporary transvenous diaphragm neurostimulation on weaning outcome and maximal inspiratory pressure. Multicenter, open-label, randomized, controlled study.

Severity stages of obesity-related breathing disorders - a cross-sectional cohort study.

Introduction: There is a general underappreciation of the spectrum of obesity-related breathing disorders and their consequences. We therefore compared characteristics of obese patients with eucapnic obstructive sleep apnea (OSA), OSA with obesity-related sleep hypoventilation (ORSH) or obesity hypoventilation syndrome (OHS) to identify the major determinants of hypoventilation.

Patients And Methods: In this prospective, diagnostic study (NCT04570540), obese patients with OSA, ORSH or OHS were characterized applying polysomnography with transcutaneous capnometry, blood gas analyses, bodyplethysmography and measurement of hypercapnic ventilatory response (HCVR).

Only I Know Now, of Course, How to Deal With it, or Better to Deal With it: A Mixed Methods Phase II Study of a Cognitive and Behavioral Intervention for the Management of Episodic Breathlessness.

Context: Episodic breathlessness is characterized by increased breathlessness intensity, and it is burdensome for patients. A vicious cycle of breathlessness-anxiety/panic-breathlessness leads to emergencies that can rarely be alleviated by drugs. Non-pharmacological interventions seem to be beneficial: Can a brief cognitive and behavioral intervention help patients to better manage episodic breathlessness?

Objectives: To evaluate the feasibility, safety, acceptability, and potential effects of a brief cognitive and behavioral intervention for the management of episodic breathlessness.

Sleep-Disordered Breathing and Nocturnal Hypoxemia in Precapillary Pulmonary Hypertension: Prevalence, Pathophysiological Determinants, and Clinical Consequences.

Background And Objective: The clinical relevance and interrelation of sleep-disordered breathing and nocturnal hypoxemia in patients with precapillary pulmonary hypertension (PH) is not fully understood.

Methods: Seventy-one patients with PH (age 63 ± 15 years, 41% male) and 35 matched controls were enrolled. Patients with PH underwent clinical examination with assessment of sleep quality, daytime sleepiness, 6-minute walk distance (6MWD), overnight cardiorespiratory polygraphy, lung function, hypercapnic ventilatory response (HCVR; by rebreathing technique), amino-terminal pro-brain natriuretic peptide (NT-proBNP) levels, and cardiac MRI (n = 34).

Effects of nasal high flow on nocturnal hypercapnia, sleep, and sympathovagal balance in patients with neuromuscular disorders.

Purpose: In neuromuscular disorders (NMD), inspiratory muscle weakness may cause sleep-related hypoventilation requiring non-invasive ventilation (NIV). Alternatively, nasal high flow therapy (NHF) may ameliorate mild nocturnal hypercapnia (NH) through washout of anatomical dead space and generation of positive airway pressure. Ventilatory support by NIV or NHF might have favourable short-term effects on sympathovagal balance (SVB).

Heart Failure Results in Inspiratory Muscle Dysfunction Irrespective of Left Ventricular Ejection Fraction.

Background: Exercise intolerance in heart failure with reduced ejection fraction (HFrEF) or heart failure with preserved ejection fraction (HFpEF) results from both cardiac dysfunction and skeletal muscle weakness. Respiratory muscle dysfunction with restrictive ventilation disorder may be present irrespective of left ventricular ejection fraction and might be mediated by circulating pro-inflammatory cytokines.

Objective: To determine lung and respiratory muscle function in patients with HFrEF/HFpEF and to determine its associations with exercise intolerance and markers of systemic inflammation.

Effects of nasal high flow on sympathovagal balance, sleep, and sleep-related breathing in patients with precapillary pulmonary hypertension.

Background: In precapillary pulmonary hypertension (PH), nasal high flow therapy (NHF) may favorably alter sympathovagal balance (SVB) and sleep-related breathing through washout of anatomical dead space and alleviation of obstructive sleep apnea (OSA) due to generation of positive airway pressure.

Objectives: To investigate the effects of NHF on SVB, sleep, and OSA in patients with PH, and compare them with those of positive airway pressure therapy (PAP).

Methods: Twelve patients with PH (Nice class I or IV) and confirmed OSA underwent full polysomnography, and noninvasive monitoring of SVB parameters (spectral analysis of heart rate, diastolic blood pressure variability).

Effects of central apneas on sympathovagal balance and hemodynamics at night: impact of underlying systolic heart failure.

Background: Increased sympathetic drive is the key determinant of systolic heart failure progression, being associated with worse functional status, arrhythmias, and increased mortality. Central sleep apnea is highly prevalent in systolic heart failure, and its effects on sympathovagal balance (SVB) and hemodynamics might depend on relative phase duration and background pathophysiology.

Objective: This study compared the effects of central apneas in patients with and without systolic heart failure on SVB and hemodynamics during sleep.

Respiratory Muscle and Lung Function in Lung Allograft Recipients: Association with Exercise Intolerance.

Background: In lung transplant recipients (LTRs), restrictive ventilation disorder may be present due to respiratory muscle dysfunction that may reduce exercise capacity. This might be mediated by pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6).

Objective: We investigated lung respiratory muscle function as well as circulating pro-inflammatory cytokines and exercise capacity in LTRs.

Characteristics of respiratory muscle involvement in myotonic dystrophy type 1.

The pathophysiology of respiratory muscle weakness in myotonic dystrophy type 1 (DM1) remains incompletely understood. 21 adult patients with DM1 (11 men, 42 ± 13 years) and 21 healthy matched controls underwent spirometry, manometry, and diaphragm ultrasound. In addition, surface electromyography of the diaphragm and the obliquus abdominis muscle was performed following cortical and posterior cervical magnetic stimulation (CMS) of the phrenic nerves or magnetic stimulation of the lower thoracic nerve roots.

Diaphragm function does not independently predict exercise intolerance in patients with precapillary pulmonary hypertension after adjustment for right ventricular function.

Several determinants of exercise intolerance in patients with precapillary pulmonary hypertension (PH) due to pulmonary arterial hypertension and/or chronic thromboembolic PH (CTEPH) have been suggested, including diaphragm dysfunction. However, these have rarely been evaluated in a multimodal manner. Forty-three patients with PH (age 58 ± 17 years, 30% male) and 43 age- and gender-matched controls (age 54 ± 13 years, 30% male) underwent diaphragm function (excursion and thickening) assessment by ultrasound, standard spirometry, arterial blood gas analysis, echocardiographic assessment of pulmonary artery pressure (PAP), assay of amino-terminal pro-brain natriuretic peptide (NT-proBNP) levels, and cardiac magnetic resonance (CMR) imaging to evaluate right ventricular systolic ejection fraction (RVEF).

Phrenic nerve involvement and respiratory muscle weakness in patients with Charcot-Marie-Tooth disease 1A.

Diaphragm weakness in Charcot-Marie-Tooth disease 1A (CMT1A) is usually associated with severe disease manifestation. This study comprehensively investigated phrenic nerve conductivity, inspiratory and expiratory muscle function in ambulatory CMT1A patients. Nineteen adults with CMT1A (13 females, 47 ± 12 years) underwent spiromanometry, diaphragm ultrasound, and magnetic stimulation of the phrenic nerves and the lower thoracic nerve roots, with recording of diaphragm compound muscle action potentials (dCMAP, n = 15), transdiaphragmatic and gastric pressures (twPdi and twPgas, n = 12).

The nature of respiratory muscle weakness in patients with late-onset Pompe disease.

Late-onset Pompe disease (LOPD) causes myopathy of skeletal and respiratory muscles, and phrenic nerve pathology putatively contributes to diaphragm weakness. The aim of this study was to investigate neural contributions to diaphragm dysfunction, usefulness of diaphragm ultrasound, and involvement of expiratory abdominal muscles in LOPD. Thirteen patients with LOPD (7 male, 51±17 years) and 13 age- and gender-matched controls underwent respiratory muscle strength testing, ultrasound evaluation of diaphragm excursion and thickness, cortical and cervical magnetic stimulation (MS) of the diaphragm with simultaneous recording of surface electromyogram and twitch transdiaphragmatic pressure (twPdi; n = 6), and MS of the abdominal muscles with recording of twitch gastric pressure (twPgas; n = 6).

More than Heart Failure: Central Sleep Apnea and Sleep-Related Hypoventilation.

Central sleep apnea (CSA) comprises a variety of breathing patterns and clinical entities. They can be classified into 2 categories based on the partial pressure of carbon dioxide in the arterial blood. Nonhypercapnic CSA is usually characterized by a periodic breathing pattern, while hypercapnic CSA is based on hypoventilation.

Electrophysiological Properties of the Human Diaphragm Assessed by Magnetic Phrenic Nerve Stimulation: Normal Values and Theoretical Considerations in Healthy Adults.

Purpose: This study determined normal values for motor evoked potentials (MEPs) and compound muscle action potentials (CMAPs) of the diaphragm following cortical and cervical magnetic stimulation (COMS and CEMS) of the phrenic nerves in healthy adults.

Methods: Using surface electrodes, diaphragmatic MEP and CMAP were recorded in 70 subjects (34 ± 13 years, 25 men) following supramaximal cortical magnetic stimulation and CEMS at functional residual capacity and using a standardized inspiratory pressure trigger (-0.5 kPa).

Transdiapragmatic pressure and contractile properties of the diaphragm following magnetic stimulation.

Insufficient normal values exist regarding twitch transdiaphragmatic pressure (twPdi) derived from standardized cervical and cortical magnetic stimulation (MS) of the diaphragm. Therefore, 63 subjects (24 men, 39 women; 34 ± 13 years) underwent transcortical and posterior cervical MS of the diaphragm with simultaneous recording of twitch oesophageal and gastric pressures (twPes, twPgas). Following cortical MS at functional residual capacity, twPdi amplitudes showed high intra-individual variability which was markedly reduced when an inspiratory pressure trigger was applied.

Sleep-disordered breathing in patients with cardiovascular diseases cannot be detected by ESS, STOP-BANG, and Berlin questionnaires.

Sleep-disordered breathing (SDB) is highly prevalent in patients with cardiovascular diseases (CVD) and associated with poor outcome. At least 50% of heart failure (HF) patients present with SDB, equally divided in obstructive sleep apnea (OSA) and central sleep apnea (CSA). CVD patients with SDB do not always present with typical SDB symptoms.