Effect PEEP on Diaphragm

Diaphragm Disease Clinical Trial

Official title:

The Effects of Positive End-expiratory Pressure on the Position, Length and Contractibility of the Diaphragm.

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03539640
• Other study ID #: NL63905.029.17
• Status: Completed
• Phase: N/A
• Start date: April 13, 2018
• Est. completion date: May 1, 2019

Study information

• Verified date: May 2020
• Source: VU University Medical Center
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study evaluates the effect of positive end-expiratory pressure on the position, length and function of the diaphragm. During the first part of the study, physiological measurements of the diaphragm will be performed while participants receive non-invasive ventilation at different PEEP levels. During the second part of the study, MRI measurements of the diaphragm will be performed during a change in PEEP level.

Description:

In almost all mechanically ventilated patients, positive end-expiratory pressure (PEEP) is used. Its function is to prevent alveolar collapse and to maintain oxygenation. However, it has recently been found that PEEP may contribute to diaphragm weakness, which is an important problem in the intensive care unit (ICU). This study showed that mechanical ventilation with PEEP resulted in a caudal displacement of the diaphragm, since PEEP increases the end-expiratory volume. Furthermore, their study in rats showed that this displacement resulted in a reduced fiber length and sarcomere length on the short term.

After rats were ventilated with PEEP for 18 hours, it was found that adaptation of the diaphragm occurred; i.e. the number of sarcomeres were decreased. It is hypothesized that this adaptation may also occur in mechanically ventilated patients. This could lead to problems in weaning a patient off the ventilator, as PEEP is abruptly removed during a spontaneous breathing trial (SBT). This leads to a reduction in end-expiratory volume which would mean that the newly-adapted diaphragm fibers are being stretched. These stretched muscle fibers are not working at their optimal length of the force-length relation, thereby contributing to diaphragm weakness.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 22
• Est. completion date: May 1, 2019
• Est. primary completion date: December 12, 2018
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Signed informed consent

• Age = 18 years

Exclusion Criteria:

• Symptoms relating to respiratory or cardiovascular disease

• History of pneumothorax or family history of primary pneumothorax

• Obesity (defined as BMI > 30kg/m²)

• Known pregnancy

• Contraindications for the placement of a nasogastric tube (upper airway/esophageal/gastric/mouth or face pathology (e.g. recent surgery, esophageal varices, diaphragmatic hernia), nasal bleeding within the last 2 weeks or use of anticoagulants)

• Contraindications for MRI (electrical/metallic implants, claustrophobia or history in metalworking)

• Subjects who are employed at the department of intensive care adults, directly involved in the study and/or family from staff of the ICU.

Related Conditions & MeSH terms

• Diaphragm Disease

Intervention

Other:
• PEEP: 5 cmH2O
During second part of the study (MRI)
• PEEP: 10 cmH2O
During second part of the study (MRI)
• PEEP: 15 cmH2O
During second part of the study (MRI)

Locations

Country	Name	City	State
Netherlands	VU Medical Center	Amsterdam	Noord-Holland

Sponsors (1)

Lead Sponsor	Collaborator
VU University Medical Center

Country where clinical trial is conducted

Netherlands, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Expiratory abdominal muscle activity	Expiratory abdominal muscle activity during different levels of PEEP measured with surface EMG electrodes	2 hours
Other	Flow	Flow during different levels of PEEP measured by the non-invasive ventilator	2 hours
Primary	Changes in diaphragm's position	Changes in the position of the diaphragm during different PEEP levels, as measured with both ultrasound and MRI	2 hours
Primary	Changes in diaphragm's shape and length	Changes of the diaphragm's shape and length during different PEEP levels, as measured with MRI	2 hours
Primary	Changes in diaphragm's efficiency	Changes in the neuro-mechanical efficiency of the diaphragm (ratio between pressure and electrical muscle activity) during different PEEP levels, as measured with a nasogastric catheter	2 hours
Primary	Change in twitch transdiaphragmatic pressures	Twitch transdiaphragmatic pressures during different PEEP levels, as measured with magnetic stimulation of the phrenic nerves.	2 hours
Secondary	Difference between MRI and ultrasound	The difference between diaphragm parameters obtained by ultrasound and parameters obtained by MRI	2 hours