Flow-synchronized Nasal IMV in Preterm Infants

Study Overview
=================
Brief Summary
-----------------
The use of non-invasive methods of respiratory support to reduce complications of prolonged invasive mechanical ventilation in preterm infants has increased. The most common mode is nasal intermittent mandatory ventilation (NIMV). In NIMV, the interval between mechanical breaths is fixed and is determined by the frequency dialed by the clinician. Asynchrony between the infant's spontaneous breathing may exist since mechanical breaths delivered at fixed intervals can occur at different times over the inspiratory or expiratory phases of the infant's spontaneous breathing. Synchronized-NIMV is a mode similar to NIMV where the ventilator cycle is delivered in synchrony with the infant's spontaneous inspiration. This has been achieved by using techniques to detect the infant's spontaneous inspiration. The advantages or disadvantages of synchronized compared to non-synchronized NIMV remain to be determined. This study seeks to evaluate the effect of synchronized NIMV versus non-synchronized NIMV on ventilation and gas exchange in premature infants who require supplemental oxygen. The hypothesis is that the use of flow synchronized nasal intermittent mandatory ventilation (S-NIMV) in comparison to non-synchronized NIMV will improve ventilation and gas exchange and reduce breathing effort. The objective of the study is to compare the effect of flow synchronized-NIMV to non-synchronized-NIMV on tidal volume (VT), minute ventilation (VE), gas exchange, breathing effort, apnea and chest wall distortion in preterm neonates with lung disease.

Official Title
-----------------
Effects of Flow-synchronized Nasal Intermittent Mandatory Ventilation in Preterm Infants

Conditions
-----------------
Premature Infant Disease, Respiratory Insufficiency

Intervention / Treatment
-----------------
* Other: non-synchronized NIMV
* Other: Synchronized NIMV


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Preterm infants of 30 or less weeks of gestational age Receiving NIMV Requiring Fi02 > 0.21 to keep Sp02 > 90% Parental written informed consent Exclusion Criteria: Major congenital anomalies Proven sepsis within 72 hours of the study Hypotension requiring pressors within 72 hours of the study Pneumothorax or pneumomediastinum within 72 hours of the study Current suspected necrotizing enterocolitis, spontaneous perforation or severe abdominal distention
Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: NIMV followed by S-NIMV<br>During the study infants assigned to this arm will undergo a 2-hour period of non-synchronized NIMV followed by a 2-hour period of Synchronized-NIMV. | Other: non-synchronized NIMV<br>* During the study each infant will undergo a 2-hour period of NIMV at a frequency of 30 cycles per minute. NIMV will be provided by a time cycled, pressure limited neonatal ventilator (Puritan Bennett 840, Covidien, Boulder, CO).<br>Other: Synchronized NIMV<br>* During the study each infant will undergo a 2-hour period of S-NIMV at a frequency of 30 cycles per minute. S-NIMV will be provided by a time cycled, pressure limited neonatal ventilator, with leak compensation capacity and nasal flow triggered ventilation (Puritan Bennett 840, Covidien, Boulder, CO). Synchronization will be achieved by the leak compensation software and the internal sensor of the ventilator.<br>|
| Other: S-NIMV followed by NIMV<br>During the study infants assigned to this arm will undergo a 2-hour period of synchronized NIMV followed by a 2-hour period of non-synchronized NIMV. | Other: non-synchronized NIMV<br>* During the study each infant will undergo a 2-hour period of NIMV at a frequency of 30 cycles per minute. NIMV will be provided by a time cycled, pressure limited neonatal ventilator (Puritan Bennett 840, Covidien, Boulder, CO).<br>Other: Synchronized NIMV<br>* During the study each infant will undergo a 2-hour period of S-NIMV at a frequency of 30 cycles per minute. S-NIMV will be provided by a time cycled, pressure limited neonatal ventilator, with leak compensation capacity and nasal flow triggered ventilation (Puritan Bennett 840, Covidien, Boulder, CO). Synchronization will be achieved by the leak compensation software and the internal sensor of the ventilator.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Minute Ventilation | Measurements of minute ventilation (VE in ml-units/min/Kg) by respiratory inductance plethysmography during flow synchronized-NIMV will be compared to measurements during non-synchronized-NIMV | 4 hours | 
| Ttidal volume (VT) | Measurements of tidal volume (VT in ml-units/Kg) by respiratory inductance plethysmography during flow synchronized-NIMV will be compared to measurements during non-synchronized-NIMV | 4 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arterial oxygen saturation | Measurements of arterial oxygen saturation (%) by pulse oximetry obtained during flow synchronized-NIMV will be compared to measurements obtained during non-synchronized-NIMV | 4 hours | 
| fraction of inspired oxygen | Required fraction of inspired oxygen during flow synchronized-NIMV will be compared to measurements obtained during non-synchronized-NIMV | 4 hours | 
| transcutaneous carbon dioxide tension | Measurements of transcutaneous carbon dioxide tension (mmHg) obtained during flow synchronized-NIMV will be compared to measurements obtained during non-synchronized-NIMV | 4 hours | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
nasal ventilation, premature infants, synchronized ventilation, non-invasive respiratory support