Effect PEEP on Diaphragm

Amsterdam UMC, location VUmc

Status: Completed

Conditions: Diaphragm Disease

Treatments: Other: PEEP: 10 cmH2O; Other: PEEP: 5 cmH2O; Other: PEEP: 15 cmH2O

Study type: Interventional

Funder types: Other

Identifiers

NCT03539640

NL63905.029.17

Details and patient eligibility

About

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.

Full 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.

Enrollment: 22 patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

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.

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

---

22 participants in 3 patient groups

PEEP level of 5 cmH2O

Active Comparator group

Description:

During second part of the study (MRI) Diaphragm position

Treatment:

Other: PEEP: 5 cmH2O

PEEP level of 10 cmH2O

Active Comparator group

Description:

During second part of the study (MRI) Diaphragm position

Treatment:

Other: PEEP: 10 cmH2O

PEEP level of 15 cmH2O

Active Comparator group

Description:

During second part of the study (MRI) Diaphragm position

Treatment:

Other: PEEP: 15 cmH2O