Effect of Positive End Expiratory Pressure on Diaphragmatic Fraction Assessed Through Ultrasound in Intubated Patient Undergoing Assisted Ventilation

• Conditions: Positive End-expiratory Pressure; Assisted Ventilation; Diaphragm Injury

• Registration Number: NCT05125744
• Lead Sponsor: Azienda Ospedaliera di Perugia

Brief Summary

The investigators aim to assess the effects of positive end-expiratory pressure (PEEP) on diaphragmatic activity evaluated through ultrasound in patients admitted to intensive care unit (ICU) for acute respiratory failure (ARF) assisted via invasive mechanical ventilation in assisted mode.

Detailed Description

All adult critically ill patients admitted to intensive care unit (ICU) and undergoing invasive mechanical ventilation (IMV) for more than 24 hours with diagnosis of acute respiratory failure (ARF) will be screened.

The exclusion criteria will be : pregnancy, neuromuscular diseases, wounds or incision at the probe placement site, contraindications to diaphragmatic and abdominal wall unltrasound, contraindications to the placement of a specific nasogastric feeding tube (Electrical activity of the diaphragm catheter).

In all enrolled patients ventilated in assisted mode, diaphragmatic activity will be evaluated through ultrasound and electrical activity of the diaphragm (primary end point) at stepwise decreasing of PEEP level. Also, the activity of remaining respiratory muscles will be assessed through sonography at the same levels of PEEP (secondary end point) Across all study phases, patients will be sedated to assure a Richmond sedation Agitation Scale (RASS) score between 0 and -1.

The following data will be recorded for each positive end-expiratory pressure explored: dosage of sedative drugs, peripheral oxygen saturation (SpO2), inspired oxygen fraction (FiO2), inpiratory and expiratory tidal volume, respiratory rate, electrical activity of the diaphragm (Eadi) (optional data), lung aeration through ultrasound or electrical impedance tomography (optional), thickness of diaphragmatic, parasternal intercostal, external oblique, internal oblique and transversus abdominis, combined with the lung ultrasound score. Thickness is measured at both end-expiration and end-inspiration for each respiratory muscles, as indirect estimation of respiratory muscles effort, and calculated according to standard formula as follows: Thickening fraction (%) = (inspiratory thickness - expiratory thickness) / expiratory thickness \* 100. All ultrasonographic measurements will be performed bedside with patients in semi-recument position, only on the right side , using a portable ultrasound machine equipped with a linear (7.5 - 12.0 MHz) or convex (2.0 - 4.0 MHz) probe. The same protocol will be carried out in case of non invasive ventilation application after extubation, reducing PEEP and inspiratory support

Study Timeline

• Study First Submitted: 2021-10-23
• Study First Submitted QC: 2021-11-07
• Study First Posted: 2021-11-18
• Status Verified: 2022-02
• Last Update Submitted: 2022-02-26
• Study Start: 2022-03-01
• Last Update Posted: 2022-03-14
• Primary Completion: 2022-05-31
• Study Completion: 2022-08-31

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

• age > 18 years
• invasive mechanical ventilation > 48 hours

Exclusion Criteria

• pregnancy
• neuromuscular disease
• wounds or incision at the probe placement site.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Diaphragmatic thickening fraction	20 minutes	The fraction of diaphragmatic thickness variations expressed in percentage during a stepwise decrease in positive end-expiratory pressure (PEEP)

Secondary Outcome Measures

Name	Time	Method
Lung aeration	20 minutes	Lung ultrasound score during a stepwise decrease in positive end-expiratory pressure (PEEP)
Respiratory rate	20 minutes	Respiratory rate during expressed in breaths on minute ratio during a stepwise decrease in positive end-expiratory pressure (PEEP)
Electrical activity of the diaphragm (optional)	20 minutes	reflects the electrical activity of the diaphragm expressed in microvolts during a stepwise decrease in positive end-expiratory pressure (PEEP)
Inspired oxygen fraction	20 minutes	inspired oxygen fraction during a stepwise decrease in positive end-expiratory pressure (PEEP)
Peripheral oxygen saturation	20 minutes	Reflects the grade of peripheral oxygenation expressed in percentage during a stepwise decrease in positive end-expiratory pressure (PEEP)
Expiratory Tidal volume	20 minutes	Expiratory Tidal volume expressed in milliliters during a stepwise decrease in positive end-expiratory pressure (PEEP)
Accessory respiratory muscles thickening fraction	20 minutes	The fractions of accessory respiratory muscles thickening fraction expressed in percentage during a stepwise decrease in positive end-expiratory pressure (PEEP)

Trial Locations

Locations (1)

Università degli Studi di Perugia; 🇮🇹 Perugia, Umbria, Italy, Italy