Clinical Trial: Respiratory Muscle Strength and Function in Neuromuscular Disorders and Chronic Obstructive Pulmonary Disease

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational

Official Title: Multimodal Measurement of Respiratory Muscle Strength and Function: Validation of Volitional and Non-volitional Tests With Regard to Nocturnal Hypoventilation in Patients With Neuromuscular Disorders

Brief Summary:

Using an extensive set of both volitional and non-volitional tests of respiratory muscle function and strength it is the aim of this study to

  • identify disease-specific patterns of respiratory muscle impairment in different NMD and COPD
  • establish which set of tests is predictive of sleep-disordered breathing or daytime hypercapnia in patients with NMD or COPD, respectively.
  • to investigate the decline of respiratory muscle function in patients with progressive NMD and COPD along with sleep studies and capnography

Detailed Summary:

Numerous neuromuscular disorders (NMD) are characterized not only by weakness of axial and limb muscles but also by respiratory muscle and upper airway involvement. Respiratory muscle weakness first manifests as sleep-disordered breathing (SDB). SDB in neuromuscular disease mainly comprises alveolar hypoventilation but upper airway collapse may also occur because pharyngeal muscle tone is impaired by both neuromuscular weakness and sleep.

Diaphragmatic weakness and myopathy are hallmarks of advanced obstructive pulmonary disease leading to even greater impairment of gas exchange in affected patients.

Non-invasive ventilation (NIV) should be initiated in patients with diaphragm weakness if significant SDB or hypercapnic respiratory failure is present. Indication criteria for NIV include measurement of spiromanometric parameters such as forced vital capacity (FVC), maximum inspiratory pressure (MIP), or sniff nasal inspiratory pressure (SNIP). These measurements are volitional, i. e. test results are dependent on individual patient effort and may show intraindividual variance which may not properly reflect disease progression or treatment effects, respectively. Associations between volitional and non-volitional methods of respiratory muscle strength testing have been reported mainly for healthy individuals but only scarcely in patients with specific NMD.

Non-volitional tests of respiratory muscle strength include phrenic nerve conduction studies, diaphragmatic ultrasound, and magnetic stimulation of the phrenic nerves in particular. Magnetic stimulation is usually combined with esophageal and gastric manometry yielding the twitch transdiaphragmatic pressure which closely reflects diaphragmatic strength.

It is desirable to obta
Sponsor: Westfälische Wilhelms-Universität Münster

Current Primary Outcome:

  • Presence of daytime hypercapnia [ Time Frame: 1 day ]
    paCO2 > 45 mmHg
  • Presence of sleep-disordered breathing [ Time Frame: 1 day ]
    nocturnal tcCO2 > 50 mmHg, delta tcCO2 > 10 mmHg


Original Primary Outcome: Same as current

Current Secondary Outcome: twitch transdiaphragmatic pressure [ Time Frame: 1 day ]

difference between intraesophageal and intragastral pressure after posterior magnetic stimulation of the phrenic nerves


Original Secondary Outcome: Same as current

Information By: Westfälische Wilhelms-Universität Münster

Dates:
Date Received: January 24, 2017
Date Started: December 1, 2016
Date Completion: February 28, 2020
Last Updated: January 25, 2017
Last Verified: January 2017