Table 3 Diagnostic performance of slopes for systolic arterial pressure (αSAP), pulse pressure (αPP), diastolic arterial pressure (αDAP), mean arterial pressure (αMAP), stroke volume (αSV), central venous pressure (αCVP) and relative variations from baseline of systolic arterial pressure (∆SAP), pulse pressure (∆PP), diastolic arterial pressure (∆DAP), mean arterial pressure (∆MAP), stroke volume (∆SV) and central venous pressure (∆CVP) between baseline (PEEP = 5, Inspiratory Pressure = 20cmH2O) and maximum pressure level (PEEP = 30, Inspiratory Pressure = 45cmH2O) to predict fluid responsiveness during STEP-UP and STEP-DOWN lung recruitment maneuver

STEP-UP

αSAP

αPP

αDAP

αMAP

αSV

αCVP

Cut-off value (degrees)

-47.8°

-42.8°

-10.1°

-20.1°

-34.2°

20.1°

ROC AUC

0.864

0.926

0.765

0.777

0.854

0.901

Sensitivity

1

1

1

1

0.875

0.777

Specificity

0.666

0.888

0.666

0.666

0.777

1

Positive predictive value

0.75

0.9

0.75

0.75

0.777

1

Negative predictive value

1

1

1

1

0.875

0.818

Youden index

0.666

0.888

0.666

0.666

0.653

0.777

Grey zone (degrees)

[47.8°-59.6°]

[42.8°-52.1°]

[10.1°-34.2°]

[20.1°-42.8°]

[24.3°-46.1°]

[13.8°-20.1°]

∆SAP

∆PP

∆DAP

∆MAP

∆SV

∆CVP

Cut-off value (mmHg)

23

21

4

9

16

8

ROC AUC

0.901

0.920

0.777

0.790

0.753

0.883

Sensitivity

1

1

1

1

0.777

0.777

Specificity

0.666

0.777

0.666

0.666

0.777

0.888

Positive predictive value

0.75

0.818

0.75

0.75

0.777

0.875

Negative predictive value

1

1

1

1

0.777

0.8

Youden index

0.666

0.777

0.666

0.666

0.555

0.666

Grey zone (mmHg)

[23–39]

[21–28]

[4–14]

[9–23]

[0–25]

[5–9]

STEP-DOWN

αSAP

αPP

αDAP

αMAP

αSV

αCVP

Cut-off value (degrees)

55.4°

47.8°

20.4°

34.7°

43.2°

-14.1°

ROC AUC

0.777

0.815

0.666

0.685

0.666

0.877

Sensitivity

0.777

0.666

0.777

0.777

0.375

0.888

Specificity

0.777

0.888

0.666

0.666

1

0.777

Positive predictive value

0.777

0.857

0.7

0.7

1

0.8

Negative predictive value

0.777

0.727

0.75

0.75

0.643

0.875

Youden index

0.555

0.555

0.444

0.444

0.375

0.666

Grey zone (degrees)

[38.7°-67.8°]

[32.4°-52.3°]

[3.9°-36.0°]

[9.76°-50.6°]

[13.2°-43.2°]

[13.8°-20.1°]

∆SAP

∆PP

∆DAP

∆MAP

∆SV

∆CVP

Cut-off value (mmHg)

32

21

8

17

15

5

ROC AUC

0.809

0.852

0.741

0.735

0.642

0.888

Sensitivity

0.777

0.777

0.777

0.777

0.666

1

Specificity

0.888

0.888

0.777

0.777

0.666

0.666

Positive predictive value

0.875

0.875

0.777

0.777

0.666

0.75

Negative predictive value

0.8

0.8

0.777

0.777

0.666

1

Youden index

0.666

0.666

0.555

0.555

0.333

0.666

Grey zone (mmHg)

[11–46]

[13–30]

[0–16]

[4–29]

[0–25]

[5–8]