Clinical trial NCT04745845: The Impact of Noradrenaline on Ventriculo-arterial Coupling and Central Cardiovascular Energy Delivery
Official title: The Impact of Noradrenaline on Ventriculo-arterial Coupling and Central Cardiovascular Energy Delivery
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Heart Diseases
Keywords: Noradrenaline
Heart surgery
Intensive care
Cardiac physiology
Lead sponsor: St. Olavs Hospital
Sponsor class: OTHER
First posted: 2021-02-09
Enrollment: 49
Sex: ALL
Minimum age (years): 18
Maximum age (years): 99
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: BASIC_SCIENCE

Brief summary: The study aims to examine how noradrenaline in combination with venous return influences the energy transmission from heart to central circulation and arteries - also called arterio-ventricular coupling.

Detailed description: After being informed about the study 40 elective CABG patients with written informed consent will undergo assessment of their arterio-ventricular coupling postoperatively after coronary bypass graft surgery. Whilst still in deep general anesthesia on the CT ICU the study population will be assessed by echocardiographic examination (transthoracic and transesophageal), blood pressure tracing by arterial line, respiratory data and ECG in 4 different situations.

Initially the individual patient is either considered fluid responsive (SVV \>13%) og non- responsive (SVV\<13%) by using stroke volume variation assessed by echocardiography.

In case of fluid responsiveness a fluid bolus of 4ml/kg of crystalloid fluid is given until SVV drops below 13% and the patient can be considered as fluid NON responder.

Right afterwards the study patient is stabilized with a baseline dose of noradrenaline (NA) intravenously in a supine position (situation 1). Situation 2 will be a slight increase in NA dose stabilizing mean arterial pressure in a "baseline + 20mmHg" state. After reversing the NA dose back to base line level the patient is allowed a short period of rest to wean of drug effect (4-5 x t1/2, appr. 12min). Subsequently the patient is to be placed in a 20% semi upright position (Anti-Trendelenburg) causing an increase in fluid responsiveness (situation 3). Following a phase of equilibration the dose of NA is again titrated up to obtain a 20mmHg increase in mean arterial pressure (situation 4).

There will be logging of arterial pressure curve and VTI-tracing I LVOT simultaneously (ultrapower, uPWR) as well as calculation of energy delivery, cardiac power, oscillatory power and -fraction and both arterial and ventricular elastance in every of those 4 situations.

Eligibility criteria: Inclusion Criteria:

* elective coronary artery bypass graft surgery
* requirement for Noradrenaline/Norepinephrine

Exclusion Criteria:

* lack of informed consent
* patient unsuitable for mean arterial pressure (MAP) elevation of 20mmHg
* patient requiring different blood pressure range due to medical/surgical needs
* poor image quality due to patient factors

Primary outcomes:
measure: Change in Cardiac Power
timeFrame: within 30 minutes after having been stabilised on the cardiothoracic ICU after performed CABG surgery
measure: Change in Oscillatory Power Fraction
timeFrame: within 30 minutes after having been stabilised on the cardiothoracic ICU after performed CABG surgery
Secondary outcomes:
measure: Change in single beat ventricular elastance
timeFrame: within 30 minutes after having been stabilised on the cardiothoracic ICU after performed CABG surgery
measure: Change in single beat arterial elastance
timeFrame: within 30 minutes after having been stabilised on the cardiothoracic ICU after performed CABG surgery
Other outcomes:
Locations:
city: Trondheim
country: Norway
facility: St Olavs Hospital, Dep. for Anesthesia & Intensive care. Section of cardiothoracic Anesthesia and -intensive Care.
Study officials:
affiliation: St. Olavs Hospital
name: Hilde Pleym (Head of Department), md, PhD
role: STUDY_DIRECTOR
References: