Clinical trial NCT04362033: Comparison of Dynamic Fluid Responsiveness by EIT and Transpulmonary Thermodilution in Postoperative of CABG Patients
Official title: Comparison of Dynamic Fluid Responsiveness Assessed by Electrical Impedance Tomography and Transpulmonary Thermodilution in Postoperative of Coronary Artery Bypass Grafting Patients
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Coronary Artery Bypass Grafting
Fluid Therapy
Stroke Volume
Hemodynamic Monitoring
Keywords: cardiac surgery
fluid responsiveness
transpulmonary thermodilution
electrical impedance tomography
passive leg raising
stroke volume variation
Lead sponsor: University of Sao Paulo
Sponsor class: OTHER
Collaborators: name: University of Sao Paulo
First posted: 2020-04-24
Enrollment: 28
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: Patients will be submitted to two different fluid responsiveness maneuvers in a cross over randomization.
Primary purpose: DIAGNOSTIC

Brief summary: The purpose of this study is to evaluate the stroke volume variation measured by both methods: transpulmonary thermodilution and electrical impedance tomography (EIT), during fluid responsiveness maneuvers and after fluid replacement in the immediate postoperative of coronary artery bypass grafting (CABG) patients. Patients will be hemodinamically monitored with the VolumeView set in combination with EV1000 clinical platform and the display of valuable volumetric parameters (Edwards Lifesciences, California, USA). Simultaneoulsy, patients will be monitored with Enlight Electrical Impedance Tomography (Timpel, São Paulo, Brazil). Hemodynamic data will be assessed at baseline 1, one minute after the passive leg raising maneuver, after PEEP increment, and after 500 mL of Lactated Ringer's (bolus infusion). Blood gases sample will be assessed before and immediatly after the protocol.

Detailed description: In the ICU, immediately after CABG surgery, patients are submitted to mechanical ventilation (volume-controlled mode with tidal volume = 8mL/Kg of PBW, PEEP = 8cmH2O and FiO2 = 60%, respiratory rate to maintain PaCO2 = 35 - 45 mmHg); hemodynamically monitored with VolumeView set in combination with EV1000 clinical platform and the display of volumetric parameters (Edwards Lifesciences, California, USA). Electrical impedance tomography monitoring (Enlight, Timpel, São Paulo, Brazil) is performed with a pair of electrodes belt attached around the thorax at 4Th - 6Th intercostal space, and a flow sensor attached between the orotracheal tube and the Y connector from the ventilator.

Before initiate the protocol, patients are submitted to a bolus of usual care doses of sedation and muscular blockage (Fentanyl, Midazolam and Cisatracurium).

To assess fluid responsiveness patients will be submitted to two different maneuvers applied in a random way: Passive Leg Raising (PLR) ant PEEP increment (PEEP). And after these maneuvers patients will receive a bolus of 500 ml of Lactated Ringer's.

Measurements are performed one minute after each of these conditions:

* Baseline: before both fluid responsiveness maneuvers, before and after Lactated Ringer infusion, patient is positioned in 450 semi-recumbent position;
* PLR: Fluid responsiveness maneuver which patient is positioned from 450 semi-recumbent position to dorsal decubitus and the legs are raised at 450;
* PEEP increment: Fluid responsiveness maneuver which consisted in increased the PEEP level 5 cmH2O above the mean airway pressure, patient is positioned in 450 semi-recumbent position
* Infusion of 500 mL of Ringer's; 450 semi-recumbent position.

Transpulmonary Thermodilution assessment are performed by the injection of 3 cold salines in bolus - the injection volume varied from 10 - 20mL according to the patient's actual weight and EIT assessment are performed by 1 injection of 10 mL of hypertonic saline at 7.5 - 10% according to the patient's actual weight.

Eligibility criteria: Inclusion Criteria:

* Elective CABG surgery
* Age greater than 18 years old and less than 80 years old
* Written inform consent

Exclusion Criteria:

* Previous pulmonary disease or pulmonary hypertension
* Previous renal replacement therapy
* Left ventricular ejection fraction \< 40%
* Body mass index \> 40 kg/m2
* Atrial fibrillation
* Presence of cardiac pacemaker or another implantable electronic device
* Bleeding associated to hemodynamic instability
* Cardiac arrest or suspicion of neurological alteration
* Hemodynamic instability (norepinephrine dose \> 0.5 mcg/Kg/min)

Primary outcomes:
measure: Difference between the variation of the stroke volume and impedance variation (mean difference in %)
timeFrame: within 2 hours after patient admission in the ICU
measure: Correlation between the variation of the stroke volume and impedance variation
timeFrame: within 2 hours after patient admission in the ICU
Secondary outcomes:
measure: Agreement between stroke volume variation (delta) (mean difference in %, CI and limits of agreement)
timeFrame: within 2 hours after patient admission in the ICU
measure: Agreement between stroke volume variation (SVV) delta during PLR maneuver and with the infusion of volume
timeFrame: within 2 hours after patient admission in the ICU
measure: To evaluate the ability of increment of PEEP to predict fluid responsiveness
timeFrame: within 2 hours after patient admission in the ICU
measure: Safety of assessment stroke volume by EIT during fluid responsiveness Test (delta of Sodium, in mEq/mL)
timeFrame: within 2 hours after patient admission in the ICU
Other outcomes:
Locations:
city: Sao Paulo
country: Brazil
facility: Heart Institute
state: SP
Study officials:
References:
citation: Braun F, Proenca M, Wendler A, Sola J, Lemay M, Thiran JP, Weiler N, Frerichs I, Becher T. Noninvasive measurement of stroke volume changes in critically ill patients by means of electrical impedance tomography. J Clin Monit Comput. 2020 Oct;34(5):903-911. doi: 10.1007/s10877-019-00402-z. Epub 2019 Oct 17.