Extubation Readiness and Neuroventilatory Efficiency After Acute Respiratory Failure

Study Overview
=================
Brief Summary
-----------------
The aim of this study was to compare the indices of rapid shallow breathing, neuromechanical efficiency (NME), and neuroventilatory efficiency (NVE) between patients being successfully extubated and those who failed weaning.

Detailed Description
-----------------
Patients, mechanically ventilated for > 24 h, were included when they met criteria for their first spontaneous breathing trial (SBT) on continuous positive airway pressure (CPAP) (5-6 cmH2O) for 30 minutes. Patients who did not fulfill the criteria for successful SBT, or required assist, or deceased within 48h post-extubation were considered extubation failure (F). Patients who completed the SBT and remained extubated > 48 h were considered successfully extubated (S). Before and during the SBT, arterial blood gases, heart, rate, blood pressure, and EAdi, flow, Vt, f, and, airway pressure (Paw) were measured. At 0, 5, 10, 15 and 30 minutes of the SBT, f/Vt, diaphragm electrical activity (EAdi), NME, and NVE were calculated. NME was calculated as Paw/EAdi during inspiratory occlusion. NVE was calculated as Vt/EAdi during unassisted inspirations.Arterial blood gases, heart rate, and blood pressure were measured. The receiver operating characteristic (ROC) curve was calculated to evaluate the predictive performance of each index.

Official Title
-----------------
Department of Critical Care Medicine, Nanjing Zhong-Da Hospital, Southeast University School of Medicine, China; Department of Critical Care Medicine St. Michaels's Hospital, University of Toronto, Canada

Conditions
-----------------
Respiratory Failure

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: We chose a number of eligible patients which were admitted to ICU of the Zhong-Da Hospital and required mechanical ventilation for more than 24 h. Exclusion Criteria: (1) age <18 or >85 years, (2) tracheostomy, (3) treatment abandonment, (4) history of esophageal varices, (5) gastro-esophageal surgery in the previous 12 months or gastro-esophageal bleeding in the previous 30 days, (6) coagulation disorders (INR ratio>1.5 and APTT>44 s), (7) history of acute central or peripheral nervous system disorder or severe neuromuscular disease, (8) history of leukemia, severe chronic liver or chronic cardiac disease, (9) solid organ transplantation, (10) malignant tumor

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
-----------------
All

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

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

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Weaning failure<br>Weaning failure:(1) failed SBT; (2) reintubation and /or resumption of support following successful extubation; or (3) die 48h following extubation. | |
| Weaning successful<br>Weaning successful:extubation and the absence of ventilatory support 48 h following the extubation | |

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

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Neuroventilatory Efficiency (NVE) | NVE is the ratio of tidal volume and diaphragm electrical activity (Vt/EAdi).It is a value describing how effective a patient's breathing is. | at 30 minutes of the spontaneous breathing trials (SBT) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Neuromechanical Efficiency (NME) | NME is the ratio between inspiratory pressure generation and EAdi (Paw/EAdi). | at 30 minutes of the spontaneous breathing trials (SBT) | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
neuromechanical efficiency, neuroventilatory efficiency, weaning, Respiration, Artificial