The Impact of Noradrenaline on Ventriculo-arterial Coupling and Central Cardiovascular Energy Delivery

St. Olavs Hospital

Status: Completed

Conditions: Heart Diseases

Treatments: Procedure: Noradrenalin

Study type: Interventional

Funder types: Other

Identifiers

NCT04745845

2019/287

Details and patient eligibility

About

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.

Full 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.

Enrollment: 49 patients

Sex: All

Ages: 18 to 99 years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Basic Science

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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49 participants in 1 patient group

Noradrenalin

Experimental group

Description:

treatment with 2 different NA concentrations in 2 different states of fluid responsiveness

Treatment:

Procedure: Noradrenalin

Procedure: Noradrenalin

Procedure: Noradrenalin

Procedure: Noradrenalin