Respiratory Failure
Conditions
Keywords
neuromechanical efficiency, neuroventilatory efficiency, weaning, Respiration, Artificial
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.
Interventions
None listed
Sponsors
Unity Health Toronto
Southeast University, China
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Neuroventilatory Efficiency (NVE) | at 30 minutes of the spontaneous breathing trials (SBT) | 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. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Neuromechanical Efficiency (NME) | at 30 minutes of the spontaneous breathing trials (SBT) | NME is the ratio between inspiratory pressure generation and EAdi (Paw/EAdi). |
Countries
China
Participant flow
Recruitment details
In a 20 beds general ICU of a teaching hospital, from December 2008 to May 2010, 52 patients , mechanically ventilated for \> 24 h, were included when they deemed ready for extubation by the clinical team and fulfilled established weaning criteria.
Pre-assignment details
Nasogastric tube Eligible patient was replaced with a modified EAdi catheter (Maquet, Solna, Sweden). Then the patients were switched to a Servo-i ventilator capable of processing signals of EAdi automatically.
Participants by arm
| Arm | Count |
|---|---|
| Weaning Failure Weaning failure:(1) failed spontaneous breathing trials (SBT); (2) reintubation and /or resumption of support following successful extubation; or (3) die 48h following extubation. | 17 |
| Weaning Successful Weaning successful:extubation and the absence of ventilatory support 48 h following the extubation | 35 |
| Total | 52 |
Baseline characteristics
| Characteristic | Weaning Successful | Weaning Failure | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 22 Participants | 16 Participants | 38 Participants |
| Age, Categorical Between 18 and 65 years | 13 Participants | 1 Participants | 14 Participants |
| Age Continuous | 65.2 years STANDARD_DEVIATION 18.5 | 76.0 years STANDARD_DEVIATION 6.4 | 68.8 years STANDARD_DEVIATION 16.4 |
| Region of Enrollment China | 35 participants | 17 participants | 52 participants |
| Sex: Female, Male Female | 11 Participants | 9 Participants | 20 Participants |
| Sex: Female, Male Male | 24 Participants | 8 Participants | 32 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 17 | 0 / 35 |
| serious Total, serious adverse events | 0 / 17 | 0 / 35 |
Outcome results
Primary
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.
Time frame: at 30 minutes of the spontaneous breathing trials (SBT)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Weaning Failure | Neuroventilatory Efficiency (NVE) | 17.6 ml/uV | Standard Deviation 10.7 |
| Weaning Successful | Neuroventilatory Efficiency (NVE) | 39.9 ml/uV | Standard Deviation 23.9 |
p-value: <0.05t-test, 2 sided
Secondary
Neuromechanical Efficiency (NME)
NME is the ratio between inspiratory pressure generation and EAdi (Paw/EAdi).
Time frame: at 30 minutes of the spontaneous breathing trials (SBT)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Weaning Failure | Neuromechanical Efficiency (NME) | 1.13 cmH2O/uV | Standard Deviation 0.71 |
| Weaning Successful | Neuromechanical Efficiency (NME) | 1.77 cmH2O/uV | Standard Deviation 0.79 |
p-value: <0.05t-test, 2 sided