Hypoxia, Myocardial Ischemia
Conditions
Keywords
Cardiac surgery, Ventilation
Brief summary
The goal of the proposed pilot study is to determine which method can detect myocardial ischemia at the predefined timepoints during endo-CABG. Additionally, the investigators want to examine the influence of mechanical ventilation on the occurrence of myocardial ischemia in patients undergoing endo-CABG.
Detailed description
CABG is the most effective therapy for patients suffering from coronary artery disease, a condition which annually affects 126 million people worldwide. During this surgery, cardiopulmonary bypass (CPB) takes over the function of the heart and lungs. As a result of the emergence of minimally invasive cardiac surgery (MICS) (e.g. endoscopic-CABG), peripheral CPB with femoral arterial cannulation became the most commonly utilized strategy. However, the use of retrograde arterial perfusion is not without risk. It may result in the upper body and coronary arteries being perfused with deoxygenated blood. The hypoxemia will induce myocardial ischemia and this can harm the cardiac myocytes. A solution for this inconvenience is still lacking. Literature reports that establishing adequate ventilation support should help overcome this phenomenon. However, this approach has not yet been investigated in a clinical trial. In general, this phenomenon is not well recognized in the typical surgical setting, and limited research has been done. The goal of the proposed pilot study is to determine which method can detect myocardial ischemia at the predefined timepoints during endo-CABG. Additionally, the investigators want to examine the influence of mechanical ventilation on the occurrence of myocardial ischemia in patients undergoing endo-CABG.
Interventions
PROCEDUREContinued ventilation
Ventilation is continued from going on CPB until clamping of the ascending aorta with tidal volume 3ml/kg ideal body weight, Fraction of inspired oxygen (FiO2) 50%, respiratory rate 5/min and Inspiratory:Expiratory (I/E) ratio 1/2.
PROCEDUREDiscontinued ventilation
Ventilation is discontinued after going on CPB and lungs are exposed to atmospheric pressure
Sponsors
Jessa Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age \> 18 years old * Patients undergoing their first elective endo-CABG procedure * Patients capable of signing the informed consent * Patients able to speak Dutch or French
Exclusion criteria
* Ongoing participation in another trial * Ejection fraction \< 50% * Lung diseases (COPD, asthma) * Use of corticosteroids
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| The detection of myocardial ischemia using Creatine Kinase Myocardial Band (CK-MB) | Until 48 hours after clamping the aorta | If the value of Creatine Kinase Myocardial Band (CK-MB) exceeds 6.2 µg/L, then CK-MB is able to detect myocardial ischemia at the predefined time points. |
| The detection of myocardial ischemia using Cardiac Troponin T (cTn-T) | Until 72 hours after clamping the aorta | If the value of Cardiac Troponin T (cTn-T) exceeds 14 ng/L, then cTn-T is able to detect myocardial ischemia at the predefined time points. |
| The detection of myocardial ischemia using Heart-type Fatty Acid Binding Protein (hFABP) | Until 5 hours after clamping the aorta | If the value of Heart-type Fatty Acid Binding Protein (hFABP) exceeds 6 ng/L, then hFABP is able to detect myocardial ischemia at the predefined time points. |
| The detection of myocardial ischemia using Reactive Oxygen Species (ROS) | Until unclamping the aorta (on average until 64 minutes after clamping the aorta) | Reactive Oxygen Species (ROS) measurements include a malondialdehyde assay to assess the lipid peroxidation, an Oxystat test to analyse the total peroxide levels and a protein carbonyl assay to assess the protein damage due to cardiomyocyte dysfunction. Additionally a biopsy will be taken to analyze pro- and anti-oxidants. If a significant increase in lipid peroxidation, total peroxide levels, protein damage and/or pro- and anti-oxidants in the ventilation group compared to the control group is present, then ROS is able to detect myocardial ischemia at the predefined time points. |
| The occurence of hypoxemia using blood gas measurement | Until the end of surgery (on average until 203 minutes after the start of the surgery) | If the partial pressure of oxygen (PaO2) is lower than 60 mmHg, then hypoxemia is present. |
Countries
Belgium
Outcome results
None listed