Anemia
Conditions
Brief summary
Mixed venous oxygen saturation is known to reflect oxygen delivery and, thus, is frequently monitored in patients undergoing cardiac surgery. Factors that affect mixed venous oxygen saturation include hemoglobin level, arterial oxygen saturation and arterial oxygen partial pressure. Among them, arterial oxygen partial pressure is known to have minimal effect on oxygen delivery compared to hemoglobin and arterial oxygen saturation. However, some argues that in certain clinical setting, such as anemia which is very common in cardiac surgery patients, the contribution of plasma (arterial oxygen partial pressure in this case) to oxygen delivery becomes more significant. Therefore, we planned to perform a pilot clinical trial to observe the change of oxygen delivery, which would be reflected in mixed venous oxygen saturation and cerebral regional oxygen saturation, according to hemoglobin level.
Interventions
OTHERChange of the fraction of inspired oxygen
After the stabilization of cardiopulmonary bypass, in the first half of patients, fraction of inspired oxygen would be set at 0.5 and maintained for 5 minutes (T0), then it would be changed to 1.0 and maintained for 5 minutes (T1). Again, fraction of inspired oxygen would be resumed to be 0.5 and maintained for 5 minutes (T2). In the other half of patients, the direction of change in fraction of inspired oxygen will be reversed as follows. It will be set at 1.0 and maintained for 5 minutes (T0), then changed to 0.5 and maintained for 5 minutes (T1), and finally to 1.0 and maintained for 5 minutes (T2).
Sponsors
Seoul National University Hospital
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
19 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients that scheduled to undergo cardiac surgery using cardiopulmonary bypass.
Exclusion criteria
* Emergent surgery * Symptomatic carotid artery stenosis or carotid artery stenosis of ≥50% * Preoperative oxygen therapy that is equivalent to the inspired oxygen fraction of 0.5.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mixed venous oxygen saturation | From the beginning and the stabilization of cardiopulmonary bypass to 15 minutes thereafter. | Change of mixed venous oxygen saturation according to the fraction of inspired oxygen |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Cerebral regional oxygen saturation | From the beginning and the stabilization of cardiopulmonary bypass to 15 minutes thereafter. | Change of cerebral regional oxygen saturation according to the fraction of inspired oxygen |
Countries
South Korea
Outcome results
None listed