ARDS, Human, Ventilation Therapy; Complications, Alveolar; Disorder
Conditions
Brief summary
The corner stone of the treatment of ARDS is mechanical ventilation with high levels of positive end-expiratory pressure, also called PEEP. A high level of PEEP is recommended and frequently used. But PEEP can lower cardiac output and contribute to circulatory failure during mechanical ventilation. Nevertheless, in theory, the PEEP-induced pulmonary vascular resistance (PVR) increase could depend on the level of alveolar recruitment, but it has never been proven. Thus, the aim of this study is to determine the relation between the high-PEEP induced PVR and the alveolar recruitment or overdistension.
Detailed description
During acute respiratory distress syndrome (ARDS) the application of positive end-expiratory pressure (PEEP) prevents expiratory alveolar collapse. However, it can induce a predominant recruitment effect or, on the contrary, alveolar overdistension. The recruitment/overdistension ratio can be easily assessed using R/I ratio (or recruitment-to-inflation ratio). However, PEEP is likely to lower cardiac output and contribute to the cardiovascular failure that often occurs in patients with ARDS. Among its hemodynamic effects, PEEP is likely to increase pulmonary vascular resistance and, thus, right ventricular afterload. In theory, this effect should only occur if PEEP over-distends the lung volume, compressing the extra-alveolar vessels and increasing their resistance. However, this different effect of PEEP on pulmonary vascular resistance depending on the degree of recruitment or overdistension has never been demonstrated during ARDS in humans. We retrospectively studied data collected from patients with ARDS, monitored by pulmonary artery catheter (PAC), to eventually find a correlation between the high PEEP-induced PVR increase and recruitement/overdistension profile.
Interventions
PAC already in place
DEVICEEsophagal pressure
Esophagal pressure already in place
Sponsors
Bicetre Hospital
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Inclusion criteria
* ARDS diagnosed * Invasive mechanical ventilation * Pulmonary artery catheter already in place * Esophagal pressure measure
Exclusion criteria
* Pregnancy * Prone position at inclusion * Legal protection measures
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Correlation between PVR and recruitment-to-inflation ratio | Up to hospital discharge (maximum : day 60) | PVR collected at two levels of PEEP and the R/I ratio to assess a relationship between the two variables |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Relationship between the R/I ratio and blood gas analysis | Up to hospital discharge (maximum : day 60) | Data collected from the daily blood samples, to assess a relationship between R/I and arterial oxygen pressure |
| Relationship between the R/I ratio and respiratory system compliance | Up to hospital discharge (maximum : day 60) | Ventilatory parameters collected at two levels of PEEP and R/I collected every day to assess a correlation between R/I and lung compliance |
| Relationship between right ventricle size and R/I ratio | Up to hospital discharge (maximum : day 60) | Echocardiographic data collected at two levels of PEEP and R/I collected every day to assess a relationship between R/I and changes in RV surface. |
| Relationship between PVR change and Transpulmonary gradient (TPG) according to R/I | Up to hospital discharge (maximum : day 60) | Data collected from PAC and R/I measure every day to assess the relationship between R/I and TPG at two levels of PEEP. |
Countries
France
Contacts
Primary ContactXavier Monnet, Pr
Outcome results
None listed