Cardioprotective Effects of Increased Endogenous Erythropoietin After Normobaric Oxygen Breathing

Study Overview
=================
Brief Summary
-----------------
Tissue hypoxia is the only accepted trigger for erythropoietin (EPO) production. However, in healthy subjects EPO concentrations have also increased after oxygen breathing. The aim of our study is to confirm these observations. Besides its main function in erythropoiesis, EPO has also shown tissue protective effects. The second goal of our study is to observe the cardioprotective effects of increased endogenous EPO, induced after normobaric oxygen breathing.

Detailed Description
-----------------
Currently, renal tissue hypoxia is the only widely accepted trigger for erythropoietin (EPO) production. However, previous studies in healthy subjects have demonstrated that a sudden and sustained decrease in tissue oxygen level, aside from an absolute low level of tissue oxygen tension, could also act as a trigger for EPO production. To confirm these observations and to clarify an eventual role of free oxygen radicals and antioxidants, hypobaric pure oxygen will be administered to healthy subjects. The major physiologic function of EPO is thought to be the induction of erythropoiesis. However, a growing body of evidence indicates that EPO has tissue-protective effects and prevents tissue damage during ischemia. In an ex vivo proof-of-concept, protective effects of EPO have been shown in human myocardium. The second goal of our study is to observe the cardioprotective effects of increased endogenous EPO, induced after normobaric oxygen breathing.

Conditions
-----------------
Healthy, Coronary Artery Bypass Graft

Intervention / Treatment
-----------------
* Other: pure oxygen breathing versus air


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: healthy non-smokers; patients undergoing CABG under cardiopulmonary bypass Exclusion Criteria: Subjects with a pulmonary disease; subjects who have stayed at high altitude since at least 3 months; healthy subjects taking medication; patients undergoing a redo or combined cardiac surgery; patients with renal insufficiency; any emergency CABG; Patients with pulmonary disease

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: placebo<br> | Other: pure oxygen breathing versus air<br>* one group will breath pure oxygen; the other will breath air<br>|
| Active Comparator: oxygen<br> | Other: pure oxygen breathing versus air<br>* one group will breath pure oxygen; the other will breath air<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| decrease in Troponin-I values |  | 12h | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Healthy subjects, CABG, Patients undergoing coronary artery bypass graft under cardiopulmonary bypass