Respiratory Mechanics Assessment at Different Head of the Bed Elevations in Mechanically Ventilated Patients
Trial Snapshot
- Phase
- Not Applicable
- Status
- Recruiting
- Enrollment
- 40
- Locations
- 2
- Primary Endpoint
- Respiratory system compliance
Study Overview
Brief Summary
The effects of different degrees of head-of-bed elevation on respiratory mechanics are poorly explored in the literature, and no study has investigated such effects using electrical impedance tomography, esophageal and gastric balloons to identify the ideal angle for optimizing respiratory mechanics. The hypothesis is that there is a optimal degree for the respiratory mechanics.
Detailed Description
Respiratory mechanics and regional ventilation will be monitored using electrical impedance tomography (Enlight 2100, Timpel Medical®, Brazil) . Esophageal and gastric pressures will be obtained through esophageal and gastric balloon catheters (Nutrivent®) (validation concerning to modified Baydur maneuver - slope delta esophageal pressure/delta airway pressure (0,8-1,2). We are using the hardware Pneumodrive (Biônica, Recife, Brazil) to record and store the esophageal, gastric and airway pressures, these data will be analyzed using LabVIEW 7.1 (Pneumobench).
Initially, patients will be positioned at 0 degrees of head-of-bed elevation, and after stabilization of the plethysmogram, data from electrical impedance tomography, hemodynamics, and arterial blood gas will be collected (arterial blood will be drawn by a nurse or physician). Sequentially and in the same manner, the bed will be adjusted to 10, 20, 30, and 40 degrees (the same data will be collected, except for the arterial blood sample, which will only be collected at the 40-degree elevation). Then, an alveolar recruitment maneuver will be performed, followed by a PEEP titration with 10-degree of head-of-bed elevation.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Basic Science
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Patients under invasive mechanical ventilation, intubated due to respiratory failure
Exclusion Criteria
- •Hemodynamics instability, contraindication for monitoring with esophageal and gastric catheters, and Electrical impedance tomography, no authorization of medical team of the intensive care unit, and contraindication for lung recruitment maneuver
Outcomes
Primary Outcomes
Respiratory system compliance
Time Frame: At 0, 10, 20, 30, 40-degrees of head-of-bed elevation, and with titrated PEEP at 10-degrees of head-of-bed elevation
Respiratory system compliance (mL/cmH2O) will be measured using electrical impedance tomography monitoring (Enlight 2100, Timpel Medical®, Brazil).
Lung compliance
Time Frame: At 0, 10, 20, 30, 40-degrees of head-of-bed elevation, and with titrated PEEP at 10-degrees of head-of-bed elevation
Lung compliance (mL/cmH2O) will be measured offline using the esophageal pressure tracings. By knowing the respiratory system and chest wall compliance, the lung compliance will be calculated. (1/respiratory system compliance = 1/chest wall compliance + 1/lung compliance)
Chest wall compliance
Time Frame: At 0, 10, 20, 30, 40-degrees of head-of-bed elevation, and with titrated PEEP at 10-degrees of head-of-bed elevation
Chest wall compliance (mL/cmH2O) will be measured offline using the esophageal pressure tracings. Chest wall compliance = tidal volume / delta esophageal pressure
Secondary Outcomes
- Hemodynamics satefy of keeping low degrees of head of the elevation(At 0, 10, 20, 30, 40-degrees of head-of-bed elevation)
- Gastric pressure(At 0 and 40-degrees of head-of-bed elevation, and with titrated PEEP at 10-degrees of head-of-bed elevation)
- Oxygenation(At 0 and 40-degrees of head-of-bed elevation, and with titrated PEEP at 10-degrees of head-of-bed elevation)
- Pressure between patient skin surface and the mattress(At 0, 10, 20, 30, 40-degrees of head-of-bed elevation)