Cutaneous Microcirculation After Remote Ischemic Preconditioning

Study Overview
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Brief Summary
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In plastic and reconstructive surgery, treatment strategies of second-degree burns, superficial wounds and chronic wounds aim at reducing infection and improving microcirculation. Although previous studies indicate that remote ischemic preconditioning (RIPC) can accelerate wound healing, only a few studies focused on the elucidation of its mechanisms of action. Therefore, the aim of this study is to evaluate the microcirculatory effects of remote ischemic preconditioning on second-degree burns, superficial and chronic wounds in a human in-vivo setting for the first time.

Official Title
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Effects of Remote Ischemic Preconditioning in Cutaneous Microcirculation of Different Wounds

Conditions
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Burn Injury, Acute Wound, Chronic Wound

Intervention / Treatment
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* Procedure: Intervention: Remote Ischemic Preconditioning


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Group A (n=20): Consent-capable male and female patients ≥18 years of age who have sustained a second-degree burn on ≥1% and ≤30% of the surface of the body. Group B (n=20): Consent-capable male and female patients ≥18 years of age who require a skin excision for the purpose of a skin graft. The minimal size of the skin-graft donor site must not be less than 1% of TBSA. Group C (n=20): Consent-capable male and female patients ≥18 years of age suffering from a wound that has not yet healed ≥3 weeks. The minimal size of the wound site must not be less than 1% of TBSA. Group D (n=20): Consent-capable healthy male and female probands ≥18 years of age serving as sham group. None of the the criteria of groups A-C must be evident. No soft tissue injury must be evident. Exclusion Criteria: General exclusion criteria below 18 years of age wounds requiring artificial respiration, since consent for the study participation is unobtainable Exclusion Criteria Groups A, B, D: peripheral arterial occlusive disease vasculitis diabetes mellitus chronic kidney or liver disease cardiac dysfunction arterial hypo- or hypertension Anamnestic exclusion criteria ongoing immunosuppressive or chemotherapy treatment drug abuse systemic skin diseases systemic and local cortisone therapy

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Second-Degree Burn<br>Group A (n=20): Consent-capable male and female patients ≥18 years of age who have sustained a second-degree burn on ≥1% and ≤30% of the surface of the body. Intervention: Remote Ischemic Preconditioning (by Blood Pressure Cuff) | Procedure: Intervention: Remote Ischemic Preconditioning<br>* Remote Ischemik Preconditioning is performed using a Blood Pressure Cuff with a pressure slightly above patients' blood pressure on the upper arm.<br>|
| Experimental: Skin Excision (for Skin Graft)<br>Group B (n=20): Consent-capable male and female patients ≥18 years of age who require a skin excision for the purpose of a skin graft. The minimal size of the skin-graft donor site must not be less than 1% of TBSA. Intervention: Remote Ischemic Preconditioning (by Blood Pressure Cuff) | Procedure: Intervention: Remote Ischemic Preconditioning<br>* Remote Ischemik Preconditioning is performed using a Blood Pressure Cuff with a pressure slightly above patients' blood pressure on the upper arm.<br>|
| Experimental: Chronic Wound<br>Group C (n=20): Consent-capable male and female patients ≥18 years of age suffering from a wound that has not yet healed ≥3 weeks. The minimal size of the wound site must not be less than 1% of TBSA. Intervention: Remote Ischemic Preconditioning (by Blood Pressure Cuff) | Procedure: Intervention: Remote Ischemic Preconditioning<br>* Remote Ischemik Preconditioning is performed using a Blood Pressure Cuff with a pressure slightly above patients' blood pressure on the upper arm.<br>|
| Active Comparator: Intact Skin<br>Group D (n=20): Consent-capable healthy male and female probands ≥18 years of age serving as sham group. None of the the criteria of groups A-C must be evident. Intervention: Remote Ischemic Preconditioning (by Blood Pressure Cuff) | Procedure: Intervention: Remote Ischemic Preconditioning<br>* Remote Ischemik Preconditioning is performed using a Blood Pressure Cuff with a pressure slightly above patients' blood pressure on the upper arm.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in microcirculation (composite measure) | capillary blood flow [arbitrary units AU] capillary blood velocity [AU] tissue oxygen saturation [%] relative postcapillary venous filling pressure [AU] | Baseline and 1 minute post-dose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in microcirculation (areolar measure) | tissue oxygen saturation [%] tissue hemoglobin index | Baseline, while and 1 minute post-dose |