Vasopressor Use Improves Macrocirculation, But What Are Its Effects on Microcirculation?
Overview
- Phase
- Not Applicable
- Status
- Completed
- Enrollment
- 30
- Locations
- 1
- Primary Endpoint
- Central Venous Oxygen Saturation (ScvO₂) Level
Overview
Brief Summary
To manage the treatment in the intensive care unit for patients with septic shock, central venous oxygen saturation (scvO2) is used as a macrocirculatory indicator, with a target value of 70% or higher being recommended. Tissue oxygenation (stO2) measurement can be implemented to assess the microcirculation in these patients, but a specific target value has not been established yet. The investigators believe that guiding the treatment of septic shock patients based on the measurement of microcirculation using stO2 and evaluating its correlation with scvO2 can reduce mortality.
This study aims to investigate the independent impact of high-dose norepinephrine on microvascular reactivity assessed by NIRS-VOT in patients with septic shock, while also examining how these microcirculatory indices relate to the macrocirculatory marker ScvO₂.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Diagnostic
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Age 18 years or older
- •Diagnosis of septic shock
- •Receiving vasopressor and mechanical ventilation therapy
- •Presence of a central venous catheter that allows ScvO₂ sampling
- •Ability to obtain tissue oxygenation (stO₂) measurements using a NIRS probe placed on the thenar eminence
- •Written informed consent obtained from patient or legal representative
Exclusion Criteria
- •Local infection, wound, or skin lesion at the planned NIRS probe application site
- •Mean arterial pressure (MAP) \< 60 mmHg despite vasopressor therapy
- •Pregnancy
- •Inability to safely perform the vascular occlusion test (as judged by treating clinician)
- •Any condition preventing safe blood sampling or reliable stO₂ measurement
Outcomes
Primary Outcomes
Central Venous Oxygen Saturation (ScvO₂) Level
Time Frame: Baseline (first 1 hour)
Central venous oxygen saturation will be measured from a central venous blood gas sample. The ScvO₂ value obtained at baseline will be recorded.
Baseline Tissue Oxygen Saturation (stO₂_baseline)
Time Frame: Within 1 hour of enrollment
Tissue oxygen saturation will be measured non-invasively from the thenar eminence using Near-Infrared Spectroscopy (NIRS). The baseline stO₂ value will be recorded immediately before the vascular occlusion test.
Norepinephrine Equivalent Vasopressor Dose
Time Frame: Baseline (first 1 hour)
The vasopressor requirement will be expressed as the norepinephrine equivalent dose (NEq), calculated in µg/kg/min.
Minimum Tissue Oxygen Saturation During Vascular Occlusion (stO₂_min)
Time Frame: Within 1 hour of enrollment
During the vascular occlusion test (inflation of a cuff to stop arterial inflow), the lowest tissue oxygen saturation (stO₂\_min) recorded from the NIRS probe on the thenar eminence will be measured and recorded.
Maximum Tissue Oxygen Saturation After Reperfusion (stO₂_max)
Time Frame: Within 1 hour of enrollment
After release of the vascular occlusion, the highest tissue oxygen saturation (stO₂\_max) value recorded during reactive hyperemia will be measured and recorded.
Recovery Time (From stO₂_min to stO₂_max)
Time Frame: Within 1 hour of enrollment
Recovery time will be defined as the time interval between the minimum tissue oxygen saturation (stO₂\_min) during vascular occlusion and the maximum tissue oxygen saturation (stO₂\_max) after cuff release, as measured by NIRS on the thenar eminence.
Secondary Outcomes
- 28-Day All-Cause Mortality(28 days)
Investigators
Oguz Özakın
Anesthesiology and Reanimation Specialist
Gaziosmanpasa Research and Education Hospital