Effect of Airway Pressure Release Ventilation on Right Ventricular Function Assessed by Transthoracic Echocardiography

Study Overview
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Brief Summary
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Effects of APRV on right ventricular function in patients with acute respiratory distress syndrome by transthoracic echocardiography

Detailed Description
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Effects of APRV on right ventricular function in patients with acute respiratory distress syndrome(ARDS) by transthoracic echocardiography，which includes TAPSE, S' by TDI, RV FAC, tricuspid regurgitation,RVEDA/LVEDA,RV, Velocity time integration(VTI) of the left ventricular outflow tract blood flow.

Official Title
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Effect of Airway Pressure Release Ventilation(APRV) on Right Ventricular Function Assessed by Transthoracic Echocardiography

Conditions
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Ventilation Therapy; Complications, Right Ventricular Function, ARDS, Transthoracic Echocardiography

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who meet the 2012 Berlin ARDS diagnostic criteria and undergo invasive mechanical ventilation PEEP≥5cmH2O, oxygenation index≤200mmHg Endotracheal intubation and mechanical ventilation time <48h Age ≥18 years old and ≤80 years old Exclusion Criteria: Aged less than 18 years old or older than 80 years old Obese patients with BMI≥35kg/m2; Pregnant and lactating women The expected time of invasive mechanical ventilation is expected to be less than 48h Neuromuscular disease known to require prolonged mechanical ventilation Severe chronic obstructive pulmonary disease Intracranial hypertension Bullae or pneumothorax, subcutaneous emphysema, mediastinal emphysema extracorporeal membrane oxygenation(ECMO) has been performed when entering the ICU Refractory shock Severe cardiac dysfunction (New York Heart Association class III or IV, acute coronary syndrome or persistent ventricular tachyarrhythmia), right heart enlargement due to chronic cardiopulmonary disease, cardiogenic shock or heart enlargement postoperative; Failure to sign informed consent

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Right ventricular area fractional change (RV FAC) | Right ventricular area fractional change (RV FAC)is a simple and repeatable ultrasound method for evaluating RV function. Methods: The RV end-diastolic area (RVEDA) and RV end-systolic area (RVESA) were measured on the apical four-chamber section by two-dimensional ultrasound. RV FAC=(RVEDA- RVESA)/RVEDA*100%. | RV FAC monitoring was performed 1 day after APRV mechanical ventilation | 
| Tricuspid annular systolic displacement(TAPSE) | TAPSE:TAPSE is one of the most effective ultrasound methods for evaluating right ventricular function.Measurement method: TAPSE was measured on the four-chamber section of the apex of the heart by M-mode ultrasound. the sampling line was placed at the side wall of the tricuspid valve ring, parallel to the free wall of the right ventricle as far as possible, and the displacement of the tricuspid valve ring was measured from the end of diastole to the end of systole. | TAPSE monitoring was performed 1 day after APRV mechanical ventilation | 
| Tricuspid annular systolic S' velocity (TS') | TS' is an objective and accurate ultrasound technique for evaluating right ventricular function.Measurement method:The sample volume was applied to the free wall of the RV and the peak velocity of tricuspid annulus motion was measured in the four-chamber section of the apex by tissue doppler imaging (TDI). | TS' monitoring was performed 1 day after APRV mechanical ventilation | 
| Right ventricular end-diastolic area/left ventricular end-diastolic area (RVEDA/LVEDA) | RVEDA/LVEDA a simple and repeatable ultrasound method for evaluating dynamics changes of RV function.Methods: The RV end-diastolic area (RVEDA) and left ventricular(LV) end-systolic area (LVEDA) were measured on the apical four-chamber section by two-dimensional ultrasound. | RVEDA/LVEDA monitoring was performed 1 day after APRV mechanical ventilation | 
| Pulmonary circulatory resistance (PVR) | Increased PVR can lead to deterioration of RV function.Pulse Doppler imaging (PWD) was used to obtain the pulmonary artery flow spectrum from the pulmonic valve on the short axial section of the parasternal great vessels. | PVR monitoring was performed 1 day after APRV mechanical ventilation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart rate (HR) | HR is a basic element of hemodynamic index | HR monitoring was performed before APRV mechanical ventilation and 6 hours, 12 hours, Day 1, Day 2, Day 3 after APRV mechanical ventilation, and 24 hours after APRV ended | 
| Systolic blood pressure (SBP) | SBP is basic element of hemodynamic index | SBP monitoring was performed before APRV mechanical ventilation and 6 hours, 12 hours, Day 1, Day 2, Day 3 after APRV mechanical ventilation, and 24 hours after APRV ended | 
| Mean arterial pressure (MAP) | MAP represents peripheral organ perfusion pressure | MAP monitoring was performed before APRV mechanical ventilation and 6 hours, 12 hours, Day 1, Day 2, Day 3 after APRV mechanical ventilation, and 24 hours after APRV ended | 
| cardiac output (CO) | CO is an important parameter to reflect the cardiac function of patients | CO monitoring was performed before APRV mechanical ventilation and 6 hours, 12 hours, Day 1, Day 2, Day 3 after APRV mechanical ventilation, and 24 hours after APRV ended by ultrasound | 
| Stroke volume (SV) | Stroke volume is the amount of blood that the ventricle shoots out during a single heart beat. | SV monitoring was performed before APRV mechanical ventilation and 6 hours, 12 hours, Day 1, Day 2, Day 3 after APRV mechanical ventilation, and 24 hours after APRV ended by ultrasound | 
| 28-day mortality | 28-day mortality after study entry | Day 28 after study entry | 
| The number of days in ICU | The number of days in ICU(up to 90 days) | From the day subjects entered ICU to the day left ICU(up to 90 days) | 
| The number of days in hospital | The number of days in hospital(up to 90 days) | From the day subjects entered hospital to the day left hospital including death(up to 90 days) | 
| in-hospital mortality | Any death occurred during hospitalization(up to 90 days) | From the day patients admitted to hospital to the day death or discharge(up to 90 days) | 
| Sequential Organ Failure Assessment score | The higher the Sequential Organ Failure Assessment(SOFA) score, the higher the disease risk factor and the higher the mortality rate(The highest score is 24, while the lowest score is 0). | Within 2 hours admission to ICU and 24 hours after inclusion in the study | 
| Acute Physiology and Chronic Health Evaluation II score | The higher the Acute Physiology and Chronic Health Evaluation II(APACHE II) score, the higher the disease risk factor and the higher the mortality rate(the highest score is 71, while the lowest score is 0).In particular, the accuracy of group patient prediction is high. | Within 2 hours admission to ICU and 24 hours after inclusion in the study | 
| the effect of APRV ventilation time on right ventricular area fractional change (RV FAC) in ARDS patients | The RV end-diastolic area (RVEDA) and RV end- systolic area (RVESA) were measured on the apical four-chamber section by two-dimensional ultrasound. RV FAC=(RVEDA- RVESA)/RVEDA*100%. | RV FAC monitoring was performed before APRV mechanical ventilation and 6 hours, 12 hours, Day 1, Day 2, Day 3 after APRV mechanical ventilation, and 24 hours after APRV ended by ultrasound | 
| the effect of APRV ventilation time on tricuspid annular systolic displacement (TAPSE) in ARDS patients. | TAPSE was measured on the four-chamber section of the apex of the heart by M-mode ultrasound. the sampling line was placed at the side wall of the tricuspid valve ring, parallel to the free wall of the right ventricle as far as possible, and the displacement of the tricuspid valve ring was measured from the end of diastole to the end of RV systole. | TAPSE monitoring was performed before APRV mechanical ventilation and 6 hours, 12 hours, Day 1, Day 2, Day 3 after APRV mechanical ventilation, and 24 hours after APRV ended by ultrasound | 
| the effect of APRV ventilation time on tricuspid annular systolic S' velocity in ARDS patients. | Tricuspid annular systolic S' velocity is an objective and accurate ultrasound technique for evaluating right ventricular function.Measurement method:The sample volume was applied to the free wall of the RV and the peak velocity of tricuspid annulus motion was measured in the four-chamber section of the apex by tissue doppler imaging (TDI). | Tricuspid annular systolic S' velocity monitoring was performed before APRV mechanical ventilation and 6 hours, 12 hours, Day 1, Day 2, Day 3 after APRV mechanical ventilation, and 24 hours after APRV ended by ultrasound | 
| the effect of APRV ventilation time on right ventricular end-diastolic area/left ventricular end-diastolic area (RVEDA/LVEDA) in ARDS patients. | RVEDA/LVEDA：RVEDA/LVEDA a simple and repeatable ultrasound method for evaluating dynamics changes of RV function.Methods: The RV end-diastolic area (RVEDA) and LV end-systolic area (lVEDA) were measured on the apical four-chamber section by two-dimensional ultrasound. | RVEDA/LVEDA monitoring was performed before APRV mechanical ventilation and 6 hours, 12 hours, Day 1, Day 2, Day 3 after APRV mechanical ventilation, and 24 hours after APRV ended by ultrasound |