Fluid Responsiveness Prediction During Prone Position

NCT ID: NCT05898269

Last Updated: 2024-01-18

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

RECRUITING

Clinical Phase

NA

Total Enrollment

96 participants

Study Classification

INTERVENTIONAL

Study Start Date

2023-10-06

Study Completion Date

2026-10-31

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Predicting fluid responsiveness is primordial when caring for patients with circulatory shock as it allows correction of preload-dependent low cardiac output states, while preserving patients of the deleterious effects of excessive fluid resuscitation.

Patients with severe acute respiratory distress syndrome (ARDS) treated with prone positioning (PP) are a specific subset of patients, as 1) they frequently present with shock; 2) excessive fluid administration may lead to respiratory worsening due to increased hydrostatic oedema with potential subsequent worse clinical outcome; and 3) all available dynamic tests evaluating fluid responsiveness can only be performed in patients in the supine condition (which in the case of severe ARDS patients in PP occurs only for 8h over 24h). These elements warrant the development of specific tests allowing the clinician to predict fluid responsiveness with enough exactitude when caring for these patients.

We hypothesize that there exists diagnostic heterogeneity in the predictive performance of 4 clinical tests to identify fluid responsiveness in ARDS patients in PP. For the matter of this study, these 4 tests are the Trendelenburg maneuver, the end-expiratory occlusion test, the end-expiratory occlusion test associated with the end-inspiratory occlusion test, and the tidal volume challenge. The diagnostic reference of the study will be the relative change in cardiac index measured by transpulmonary thermodilution before and after a 500 ml fluid bolus, and will allow the adjudication of patients as being fluid responsive or not.

The primary objective of the study is to determine the area under the ROC curve of each of the 4 tests, with their respective 95% confidence interval.

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus. Patients will only participate once. The expected duration of study participation is 30 minutes maximum.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Acute Respiratory Distress Syndrome

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

CROSSOVER

Primary Study Purpose

OTHER

Blinding Strategy

NONE

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Trendelenburg maneuver-EE OCC-EI OCC-Tidal volume challenge

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Trendelenburg maneuver-EE OCC-Tidal volume challenge-EI OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Trendelenburg maneuver-Tidal volume challenge-EI OCC-EE OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Trendelenburg maneuver-Tidal volume challenge-EE OCC-EI OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Trendelenburg maneuver-EI OCC-Tidal volume challenge-EE OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Trendelenburg maneuver-EI OCC-EE OCC-Tidal volume challenge

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EE OCC-EI OCC-Tidal volume challenge-Trendelenburg maneuver

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EE OCC-EI OCC-Trendelenburg maneuver-Tidal volume challenge

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EE OCC-Tidal volume challenge-Trendelenburg maneuver-EI OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EE OCC-Tidal volume challenge-EI OCC-Trendelenburg maneuver

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EE OCC-Trendelenburg maneuver-Tidal volume challenge-EI OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EE OCC-Trendelenburg maneuver-EI OCC-Tidal volume challenge

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EI OCC-Tidal volume challenge-EE OCC-Trendelenburg maneuver

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EI OCC-Tidal volume challenge-Trendelenburg maneuver-EE OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EI OCC-Trendelenburg maneuver-EE OCC-Tidal volume challenge

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EI OCC-Trendelenburg maneuver-Tidal volume challenge-EE OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EI OCC-EE OCC-Trendelenburg maneuver-Tidal volume challenge

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

EI OCC-EE OCC-Tidal volume challenge-Trendelenburg maneuver

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Tidal volume challenge-EI OCC-EE OCC-Trendelenburg maneuver

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Tidal volume challenge-EI OCC-Trendelenburg maneuver-EE OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Tidal volume challenge-Trendelenburg maneuver-EE OCC- EI OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Tidal volume challenge-Trendelenburg maneuver- EI OCC-EE OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Tidal volume challenge-EE OCC-Trendelenburg maneuver- EI OCC

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Tidal volume challenge-EE OCC- EI OCC-Trendelenburg maneuver

All enrolled patients will perform the 4 tests following a cross-over design and in a randomized sequence, separated by 1-min wash-out periods with return to hemodynamic baseline values, and concluded with the 500-ml fluid bolus.

There are 24 different possibilities of sequence

Group Type EXPERIMENTAL

Trendelenburg maneuver

Intervention Type DIAGNOSTIC_TEST

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

End-expiratory occlusion test (EE OCC)

Intervention Type DIAGNOSTIC_TEST

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

End-expiratory and end-inspiratory occlusion test (EI OCC)

Intervention Type DIAGNOSTIC_TEST

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Tidal volume challenge

Intervention Type DIAGNOSTIC_TEST

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Fluid bolus (reference diagnostic method)

Intervention Type DIAGNOSTIC_TEST

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Trendelenburg maneuver

Bed tilting from the +13° position to the -13° position for 60 seconds. Evaluator: relative change in continuous cardiac index between baseline, and the highest value observed during the maneuver

Intervention Type DIAGNOSTIC_TEST

End-expiratory occlusion test (EE OCC)

End-expiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause

Intervention Type DIAGNOSTIC_TEST

End-expiratory and end-inspiratory occlusion test (EI OCC)

End-inspiratory pause performed on the ventilator, and maintained for 15 seconds.

Evaluator: relative change in continuous cardiac index between baseline, and the value observed in the last 5 seconds of the respiratory pause. The evaluator is calculated as the sum of the relative change in cardiac index observed during the end-expiratory pause and that of the end-inspiratory pause. Hence, for this test, the evaluator will be coupled with that of intervention 2 (end-expiratory occlusion test).

Intervention Type DIAGNOSTIC_TEST

Tidal volume challenge

Increase in tidal volume set on the ventilator from 6 ml.kg-1 of predicted body weight, to 8 ml.kg-1 for 60 seconds.

Evaluator: difference in the pulse pressure variation measured at 6 ml.kg-1 and at 8 ml.kg-1.

Intervention Type DIAGNOSTIC_TEST

Fluid bolus (reference diagnostic method)

After the 4 tests, the patient will receive a 500-ml fluid bolus of crystalloids in less than 15 minutes.

Evaluator (reference method): cardiac index measured by transpulmonary thermodilution before and immediately after the fluid bolus. Patients with a relative change in cardiac index \> 15% will be identified as being fluid responders, and the others as non-responders.

Intervention Type DIAGNOSTIC_TEST

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* adult patient (including patient under protective measures/wardship)
* with ARDS as defined by the Berlin criteria
* in the prone position as per international guidelines
* with a calibrated continuous cardiac output monitoring device
* with a clinical indication for a fluid bolus as prescribed by the clinician in charge, and fulfilling at least 2 clinical criteria: mottles, tachycardia, hypotension, drop in cardiac output, oliguria, high arterial lactate concentration, or any other detailed criterion
* with no respiratory efforts

Exclusion Criteria

* acute cor pulmonale
* patient treated with veno-venous extra-corporeal membrane oxygenation
* hemorrhagic shock
* Child-Pugh C cirrhosis
* death expected to occur in less than 24h
* decision to withhold or suspend active treatments
* intracranial hypertension
* lower limb amputation
* obstruction of the inferior vena cava
* acute abdominal syndrome
* absence of consent to participate
* pregnancy
* patient previously enrolled in the same study
* lack of affiliation to a social security regimen, as per French legislation
* patient deprived of its liberty
Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

Hospices Civils de Lyon

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Responsibility Role SPONSOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Hodane YONIS, Dr

Role: PRINCIPAL_INVESTIGATOR

Hospices Civils de Lyon

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

CHU Gabriel Montpied

Clermont-Ferrand, , France

Site Status NOT_YET_RECRUITING

Hôpital de la Croix Rousse, Hospices Civils de Lyon

Lyon, , France

Site Status RECRUITING

CHU de Nice - l'Archet 1

Nice, , France

Site Status NOT_YET_RECRUITING

CHU Nice - Pasteur 2

Nice, , France

Site Status NOT_YET_RECRUITING

Countries

Review the countries where the study has at least one active or historical site.

France

Central Contacts

Reach out to these primary contacts for questions about participation or study logistics.

Laurent BITKER, Dr

Role: CONTACT

4 26 10 94 93 ext. +33

Mathieu Jozwiak, Dr

Role: CONTACT

4 92 03 55 10 ext. +33

Facility Contacts

Find local site contact details for specific facilities participating in the trial.

Claire Dupuis, Dr

Role: primary

4 73 75 49 82 ext. +33

Laurent BITKER, Dr

Role: primary

4 26 10 94 93 ext. +33

Mathieu Jozwiak, Dr

Role: primary

4 92 03 55 10 ext. +33

Denis DOYEN, Dr

Role: primary

04 92 03 55 10 ext. +33

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

2023-A00920-45

Identifier Type: OTHER

Identifier Source: secondary_id

69HCL23_0315

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.

Non-invasive Fluid Management
NCT02892799 UNKNOWN NA