Clinical trial NCT03140579: Effect of PEEP on Lung Recruitment and Homogeneity Over Time in Moderate to Severe ARDS
Official title: Estimation of Long Term PEEP Effect on Lung Homogeneity and Recruitment Using APRV Ventilation:Measurement of End Expiratory Lung Volume With Nitrogen Wash-out/wash-in Technique and End Expiratory Lung Impedance With EIT at Different Times.
Study type: OBSERVATIONAL
Overall status: WITHDRAWN
Conditions: ARDS
Critical Illness
Ventilator-Induced Lung Injury
Keywords: recruitment
lung homogeneity
airway pressure release ventilation
Lead sponsor: Guy's and St Thomas' NHS Foundation Trust
Sponsor class: OTHER
First posted: 2017-05-04
Enrollment: 0
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: All Patients admitted to ICU ventilated with moderate or severe ARDS, based on the Berlin definition of ARDS.

Brief summary: This study evaluates the effect of airway pressure release ventilation (APRV) on lung homogeneity and recruitment in patients with moderate to severe acute respiratory distress syndrome (ARDS).

It will do this by comparing the homogeneity of ventilation and recruitment prior to a patient being ventilated on APRV, and at 30, 60 and 120 minutes after starting APRV.

Detailed description: Ventilator-induced lung injury (VILI) is a well-recognised problem of ventilation in patients with ARDS, and is currently treated with lung-protective ventilation, which limits tidal volumes and airway pressures by applying higher levels of positive-end expiratory pressure (PEEP). However, it is not known whether higher levels of PEEP increases recruitment and homogeneity of ventilation within the lungs.

APRV is a mode of inverse ventilation, where high levels of PEEP are maintained with brief releases of pressure, and has been proposed as an appropriate method of ventilation in patients with ARDS.

This study will assess homogeneity of ventilation and recruitment in 15 patients before APRV is started, and 30, 60 and 120 mins after commencing APRV. It will do this using Electrical Impedance Tomography (EIT), nitrogen wash in/wash out technique, and lung strain.

Eligibility criteria: Inclusion Criteria:

* Age ≥ 18 years and \< 80 years

  * Weight \> 35 Kg and BMI \< 40
  * Informed consent according to local regulations
  * Hemoglobin ≥ 70 g/dl
  * Haemodynamically stable \> 4 hours
  * Moderate to severe ARDS (PaO2/FIO2 \< 26.6 kPa with positive end-expiratory pressure (PEEP) \> 5 cmH2O) as per Berlin definition of ARDS

Exclusion Criteria:

* Expected survival \< 72 hours

  * Suspected pregnancy (negative pregnancy test required for women of child-bearing potential)
  * Open abdomen
  * Documented or suspected raised intracranial pressure
  * Active air leak (pneumothorax, pneumomediastinum, subcutaneous emphysema)
  * Morbid obesity BMI \> 40
  * Recent \< 1 week cardiac or thoracic surgery
  * Unstable thorax and sternum with paradoxical chest wall movement
  * Severe Chronic Respiratory Disease (COPD) - GOLD 3 or 4 emphysema with bullae
  * Severe smoking (\> 40 pack-year history)
  * Liver Failure: Child-Pugh Class C
  * Massive ascites
  * Lung fibrosis
  * Severe cardiac disease (one of the following): New York Heart Association Class III or IV, acute coronary syndrome or persistent ventricular tachyarrhythmias
  * Sickle cell disease

Primary outcomes:
measure: To compare lung homogeneity estimated with EIT upon commencing APRV (APRVpre) and after 30 - 60 - 120 min of APRV ventilation (APRV30, APRV60, APRV120) in patients with moderate to severe ARDS
timeFrame: 30, 60 and 120 mins
Secondary outcomes:
measure: To assess recruitment at the beginning and after the end of APRV ventilation in patients with moderate-severe ARDS.
timeFrame: 2 hours
measure: To compare lung strain measured at APRVpre and after the end of APRV ventilation (APRVpost) in patients with moderate-severe ARDS
timeFrame: 2 hours
Other outcomes:
Locations:
city: London
country: United Kingdom
facility: Guys and St Thomas NHS Foundation
Study officials:
affiliation: Guy's and St Thomas' NHS Foundation Trust
name: Luigi Camporota
role: PRINCIPAL_INVESTIGATOR
References: