RIPC During Free Flap With Preoperative Radiotherapy

Study Overview
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Brief Summary
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Remote ischemic preconditioning (RIPC) has shown organ-protective effects in many clinical settings including patients with ischemic heart disease. However its protective role in head and neck cancer patients with preoperative radiotherapy undergoing free flap reconstructive surgery has not yet been evaluated. The purpose of the current study is to evaluate the effect of RIPC on tissue oxygen saturation and skin temperature of the flap, as well as its organ-protective effects using Langendorff isolated heart ischemia-reperfusion model.

Detailed Description
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Patients undergoing free flap reconstructive surgery for head and neck cancer with preoperative radiotherapy will be randomized to either remote ischemic preconditioning (RIPC) group or control group. On the day of surgery, after induction of anesthesia, RIPC, consisting of 4 cycles of 5-min ischemia (using pneumatic cuff pressure of 200 mmHg) followed by 5-min reperfusion at the upper arm, or sham-RIPC (pressure < 10 mmHg) will be induced in the RIPC or control group, respectively. Before completion of surgery, RIPC or sham-RIPC will be repeated. Tissue oxygen saturation and skin temperature of the flap will be recorded until postoperative day 1. As a sub-study, blood samples will be obtained before and after RIPC/sham-RIPC. From them, plasma dialysate will be prepared to use for Langendorff isolated heart model. Myocardial infarct size of Langendorff rat heart will be compared between the groups to evaluate organ protective effects of RIPC during free flap reconstructive surgery.

Official Title
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Effects of Remote Ischemic Preconditioning During Free Flap Reconstruction in Head and Neck Cancer Patients With Preoperative Radiotherapy

Conditions
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Ischemic Reperfusion Injury, Other Reconstructive Surgery, Radiotherapy

Intervention / Treatment
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* Other: remote ischemic preconditioning (RIPC)
* Other: Sham-RIPC


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult head and neck cancer patients undergoing free flap reconstructive surgery with preoperative radiotherapy Exclusion Criteria: Radiotherapy within 4 weeks Body mass index < 18 kg/m^2 or > 35 kg/m^2 Presence of AV fistula at the arm, any reason to protect arms Presence of vascular abnormality or discomfort at arms Peripheral vascular disease, peripheral neuropathy, or coagulopathy Uncontrolled diabetes mellitus Preoperative use of beta-blockers Refuse to enrol

Ages Eligible for Study
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Minimum Age: 20 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: RIPC<br>Remote ischemic preconditioning (RIPC) consisted of 4 cycles of 5-min ischemia using pneumatic cuff pressure of 200 mmHg and 5-min reperfusion is applied to the upper arm of the patients in the RIPC group. | Other: remote ischemic preconditioning (RIPC)<br>* RIPC consists of 4 cycles of 5-min ischemia using pneumatic cuff pressure of 200 mmHg and 5-min reperfusion.<br>|
| Sham Comparator: Sham-RIPC<br>Sham-RIPC consisted of 4 cycles of 5-min ischemia using pneumatic cuff pressure of < 10 mmHg and 5-min reperfusion is applied to the upper arm of the patients in the Sham-RIPC group. | Other: Sham-RIPC<br>* Sham-RIPC consists of 4 cycles of 5-min ischemia using pneumatic cuff pressure of < 10 mmHg and 5-min reperfusion.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| tissue oxygen saturation | tissue oxygen saturation of the flap | postoperative day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| skin temperature | skin temperature of the flap and the adjacent tissue | postoperative day 1 | 
| myocardial infarct size of the rat Langendorff model | myocardial infarct size of the rat Langendorff model | 24 hr | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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remote ischemic preconditioning, free flap reconstruction, preoperative radiotherapy