Microcirculation
Conditions
Keywords
tissue oxygen saturation, ischemic conditioning
Brief summary
Changes in tissue microcirculation during ischemic conditioning (4 cycles of 5-min ischemia and 5-min reperfusion) has not been well documented. In previous studies, there was difference in changes in microcirculation, such as recovery slope and occlusion slope, between healthy subjects and cardiac surgery patients. Moreover, the occlusion slope, which reflects local tissue oxygen consumption during ischemic period, is anticipated to decrease during repeated ischemia-reperfusion cycle by its protecting effect, however there has not been well-conducted study. The purpose of the study is to evaluate the changes in microcirculation measured by tissue oxygen saturation during ischemic conditioning between healthy volunteers and cardiac surgery patients.
Detailed description
Subjects who are male healthy volunteers (aged 20-45) or who are scheduled to receive cardiac surgery (aged 20-80) will undergo ischemic conditioning, consisting of 4 cycles of 5-min ischemia with pressure of 200 mmHg on upper extremity followed by 5-min reperfusion with no pressure. During ischemic conditioning, changes in tissue microcirculation (baseline tissue saturation, occlusion slope during ischemia, and recovery slope during reperfusion) will be observed using tissue oxygen saturation sensor attached to the thenar muscle of the hand. For cardiac surgery patients, the study will be conducted before anesthesia induction on the surgery day to exclude any potential effect of anesthetics.
Interventions
PROCEDUREischemic conditioning
Four cycles of 5-min inflation of pneumatic cuff on upper extremity up to 200 mmHg, followed by 5-min deflation with no pressure.
Sponsors
Seoul National University Hospital
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
20 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
\<Healthy volunteers\> Inclusion Criteria: * Age 20-45 * No underlying chronic disease * Male volunteer
Exclusion criteria
* Under taking prescription drugs * Taking herbal medicines within 2 weeks * Baseline systolic blood pressure \> 150 mmHg or diastolic pressure \> 100 mmHg * Body mass index \< 18 kg/m\^2 or \> 30 kg/m\^2 * Vigorous exercise, excessive alcohol, smoking or caffeine within 24 hours * Any abnormalities on upper extremities * Do not consent to participate \<Cardiac surgery patients\> Inclusion Criteria: * Age 20-80 * Scheduled for cardiac surgery
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in microcirculation during ischemic conditioning | During 4-cycles of 5-min ischemia followed by 5-min reperfusion | Changes in occlusion slope during ischemia and recovery slope during reperfusion |
Countries
South Korea
Outcome results
None listed