Incidence of right heart dysfunction in ARDS patients with APRV or LTV mechanical ventilation for 48h
Incidence of right heart dysfunction in ARDS patients with APRV or LTV mechanical ventilation for 24h.Abnormal findings on any of the following ultrasound measures can be considered as right ventricular dysfunction, including: right ventricular end-diastolic diameter/left ventricular end-diastolic diameter(RVEDD/LVEDD)>1.0, right ventricular fractional area change(FAC)<35%,tricuspid annular plane systolic excursion(TAPSE)<17mm,Systolic S'velocity of tricuspid annulus <9.5 cm/s by TDI
Incidence of right heart dysfunction in ARDS patients with APRV or LTV mechanical ventilation for 72h
Incidence of right heart dysfunction in ARDS patients with APRV or LTV mechanical ventilation for 24h.Abnormal findings on any of the following ultrasound measures can be considered as right ventricular dysfunction, including: right ventricular end-diastolic diameter/left ventricular end-diastolic diameter(RVEDD/LVEDD)>1.0, right ventricular fractional area change(FAC)<35%,tricuspid annular plane systolic excursion(TAPSE)<17mm,Systolic S'velocity of tricuspid annulus <9.5 cm/s by TDI
Values of tricuspid annular plane systolic excursion at 24th hour
Tricuspid annular plane systolic excursion(TAPSE) was measured by echocardiography in the apical four-chamber view, using M mode measurements, with the sampling line aligned to the tricuspid annulus.
Values of tricuspid annular plane systolic excursion at 48th hour
Tricuspid annular plane systolic excursion(TAPSE) was measured by echocardiography in the apical four-chamber view, using M mode measurements, with the sampling line aligned to the tricuspid annulus.
Values of tricuspid annular plane systolic excursion at 72th hour
Tricuspid annular plane systolic excursion(TAPSE) was measured by echocardiography in the apical four-chamber view, using M mode measurements, with the sampling line aligned to the tricuspid annulus.
Values of right ventricular end-diastolic diameter/left ventricular end-diastolic diameter(RVEDD/LVEDD) at 24th hour
The maximum transverse diameter of the right/left ventricular inflow tract near the basal 1/3 was measured in the apical four-chamber view
Values of right ventricular end-diastolic diameter/left ventricular end-diastolic diameter(RVEDD/LVEDD) at 48th hour
The maximum transverse diameter of the right/left ventricular inflow tract near the basal 1/3 was measured in the apical four-chamber view
Values of right ventricular end-diastolic diameter/left ventricular end-diastolic diameter(RVEDD/LVEDD) at 72th hour
The maximum transverse diameter of the right/left ventricular inflow tract near the basal 1/3 was measured in the apical four-chamber view
Values of right ventricular fractional area change(RVFAC) at 24th hour
RVFAC = (end-diastolic area - end-systolic area)/end-diastolic area ×100%.The right ventricle is shown in the apical four-chamber cardiac view.
Values of right ventricular fractional area change(RVFAC) at 48th hour
RVFAC = (end-diastolic area - end-systolic area)/end-diastolic area ×100%.The right ventricle is shown in the apical four-chamber cardiac view.
Values of right ventricular fractional area change(RVFAC) at 72th hour
RVFAC = (end-diastolic area - end-systolic area)/end-diastolic area ×100%.The right ventricle is shown in the apical four-chamber cardiac view.
Values of Systolic S'velocity of tricuspid annulus by at 24th, 48th and 72th hour
Tissue Doppler sampling volume is placed in the middle of the right ventricular tricuspid annulus or basal segment of the right ventricular free wall to measure systolic velocity S'.
Values of hemodynamic measures at 24th, 48th and 72th hour
hemodynamic measures including: heart rate, mean arterial pressure,central venous pressure,Dose of vasoactive agents accumulated over 24 hours,cumulative fluid balance over 24 hours.
Values of respiratory mechanics parameters at 24th, 48th and 72th hour
Respiratory mechanics parameters including Peak pressure, Plateau pressure,Driving pressure,Respiratory system compliance and Airway resistance are measured by using routine procedures
28-day mortality
28-day mortality after study entry
in hospital mortality
in hospital mortality after study entry
28 days of ventilator free days
28 days of ventilator free days after study entry
Values of arterial partial pressure of oxygen/fraction of inspired oxygen at 24th, 48th and 72th hour
arterial partial pressure of oxygen/fraction of inspired oxygen are measured at 24th, 48th and 72th hour after inclusion
Values of arterial partial pressure of carbon dioxide at 24th, 48th and 72th hour
arterial partial pressure of carbon dioxide are measured at 24th, 48th and 72th hour after inclusion
ventilation ratio at 24th, 48th and 72th hour
VR=[minute ventilation ×PaCO2]/[predicted body weight ×100×37.5]
Incidence prone position ventilation during hospitalization
Incidence of prone position ventilation during hospitalization after study entry
ventilator settings at 24th, 48th and 72th hour
ventilator settings including minute ventilation, Fraction of inspired oxygen, tidal volume, positive end-expiratory pressure, respiratory rate, mean airway pressure
Velocity-time integral of left ventricular outflow tract at 24th, 48th and 72th hour
Velocity-time integral(Vti) of left ventricular outflow tract are measured at the apical five-chamber heart view. The sampling volume was placed in the left ventricular outflow tract, below the aortic valve, in pulsed Doppler mode with a window width of 2-4mm. The velocity time integral (VTI) image of aortic blood flow can be obtained by placing the sampling volume below the aortic valve orifice , adjusting the probe so that the direction of blood flow is as parallel as possible to the sampling line, and selecting the pulsed Doppler mode (PW)
Stroke volume at 24th, 48th and 72th hour
Stroke volume(SV)=15.VTI×π(D/2)*(D/2), D=Left ventricular outflow tract diameter(LVOT diameter)
cardiac output at 24th, 48th and 72th hour
cardiac output(CO)=SV*HR
Velocity-time integral of right ventricular outflow tract at 24th, 48th and 72th hour
Velocity-time integral(Vti) of right ventricular outflow tract are measured at the view of the right ventricular outflow tract. The sampling volume was placed in the right ventricular outflow tract, below the aortic valve, in pulsed Doppler mode with a window width of 2-4mm. The velocity time integral (VTI) image of aortic blood flow can be obtained by placing the sampling volume below the aortic valve orifice , adjusting the probe so that the direction of blood flow is as parallel as possible to the sampling line, and selecting the pulsed Doppler mode (PW)
Tricuspid annular diameter
Tricuspid annular diameters are measured at the apical four-chamber heart view
The velocity of tricuspid regurgitation
The velocity of tricuspid regurgitation are measured at the apical four-chamber heart view.The CW Doppler sampling line was placed at the tricuspid valve orifice.
Length of hospital stay
hospital stay after hospital entry
Length of ICU stay
hospital stay after ICU entry
Incidence of tracheotomy
Incidence of tracheotomy during hospitalization after study entry