Non-Invasive Ventilation Versus Continuous Positive Airway Pressure in Cardiogenic Pulmonary Edema: a Multicentre Study
Non-invasive ventilation (NIV) has become now a widely used treatment modality in ICU and emergency services to deal with respiratory failure.1 NIV has the potential to improve ventilatory assistance while avoiding endotracheal intubation and its complications.
Since the first publications of Meduri2 and Brochard3 the number of studies on the NIV has been growing and developing and this technique becomes one of the major progress in the field of respiratory assistance. Decompensation of chronic obstructive pulmonary disease (COPD) is certainly the least questionable indication of the NIV. However, indication of the NIV is inexorably spreading to other types of acute respiratory insufficiency, including acute cardiogenic pulmonary edema (CPE).4 Continuous positive airway pressure (CPAP) is the most currently used non-invasive ventilation usually performed without the use of a ventilator. NIV using pressure support (NIPSV) combined pressure support (inspiratory aid) and positive expiratory pressure as in CPAP. Based on physiological ground, NIPSV would be more performant than CPAP to improve ventilatory parameters and reduce the work breathing in APE. However, this issue is not settled yet. Number of meta-analysis over the last 2 years were devoted to the comparison of CPAP and NISPV,5 so that the scientific evidence is still far from established. In addition, it is not sur that patients enrolled in these studies are representative of all patients with APE. The fact that they were included solely on the basis of clinical criteria, the risk of overlap with other diagnoses is not negligible. Thus the use of markers of heart failure as the BNP (brain natriuretic peptide) would be very useful. On the other hand, the possible deleterious effect of NIPSV on myocardial perfusion is a problem that has not been definitively resolved.
Objectives of the study:
- Compare the efficacy and safety of the NIPSV with those of CPAP in patients presenting to the emergency department with CPE.
- Compare the two procedures in subgroups of patients with hypercapnia and high BNP concentration.
|Cardiogenic Pulmonary Edema||Device: continuous positive airway pressure Device: noninvasive pressure support ventilation||Phase 3|
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
- It is the combination of 3 events: the need for endotracheal intubation, hospital death, and ICU hospitalisation. [ Time Frame: 6 hours and 30 days after protocol start ]
- Primary outcome It is the combination of 3 events: the need for endotracheal intubation, hospital death, and ICU hospitalisation. [ Time Frame: 6 hours and 30 days after protocol start ]
- The change in the rate of troponin [ Time Frame: 6 hours after protocol start ]
- The length of hospital stay [ Time Frame: 30 days after protocol start ]
|Study Start Date:||January 2005|
|Study Completion Date:||July 2008|
|Primary Completion Date:||June 2008 (Final data collection date for primary outcome measure)|
Active Comparator: continuous positive airway pressure
Device: continuous positive airway pressure
respiratory assistance using face mask and positive expiratory pressure apllied by a Boussignac valve
Other Name: Boussignac CPAP
Active Comparator: NIPSV
respiratory assistance using face mak and ventilator to provide inspiratory pressure support and positive end expiratory pressure
Device: noninvasive pressure support ventilation
noninvasive pressure support ventilation can provide inspiratory pressure support and expiratory positive pressure
Other Name: NIPSVDevice: noninvasive pressure support ventilation
noninvasive pressure support ventilation provides an inspiratory aid and positive expiratory pressure using ventilator through face mask
Other Name: NIPSV
Cardiogenic pulmonary edema is defined as an increase of hydrostatic pressure in the pulmonary microcirculation resulting from postcapillaire hypertension.
The direct consequence is extravasation of fluid in the alveolar and interstitial tissue, leading to acute hypoxemia and a decrease in lung compliance. The decrease in lung compliance, increased airway resistance (interstitial and bronchial edema) and hypoxemia will cause an increase in work of breathing. The imbalance between the ability of respiratory muscles to generate effective gas exchange and exaggerated ventilatory load can lead to respiratory muscle fatigue requiring use of mechanical ventilation through endotracheal prosthesis. In addition, the increase in inspiratory muscles work during the CPE generates very important pleural depression, which increases transmural pressure and left ventricular afterload and thus increases pulmonary edema.
The CPAP is a non-invasive ventilation mode most currently used CPE. It is usually obtained via a mask and an expiratory valve to maintain constant pressure in the circuit. No inspiratory assistance is provided to the patient. The BOUSSIGNAC valve is currently used in clinical practice as an adjunct to the pharmacological treatment of CPE.The effect of CPAP is mainly linked to its ability to recruit zones that are collapsed during expiration. • NIPSV combines a positive expiratory pressure to ventilatory assistance pressure during inspiration delivered by a ventilator. It corresponds to a CPAP associated with inspiratory assistance, and thus, it is likely to improve the ventilation parameters, and in particular to reduce respiratory work more efficiently than CPAP alone.These beneficial physiological effects of NIPSV were well demonstrated during the decompensation of COPD ; they wait to be confirmed during CPE. Physiological studies have shown that the NIPSV is more effective in terms of reducing the work of breathing in CPE. However, none of the 7 published randomized studies has shown superiority of the NIPSV compared to CPAP in terms of reducing mortality and intubation requirement