The Effect of High Dose Arginine Infusion on Hemodynamic and Peripheral Microcirculation

Study Overview
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Brief Summary
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The aim of this study was to investigate the effect of a 24- hrs L-arginine infusion on hemodynamic and on parameters of microcirculation in patients with peripheral arterial occlusive disease (PAOD).

Official Title
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The Effect of High Dose Arginine Infusion on Hemodynamic and Peripheral Microcirculation: a Randomized, Controlled Clinical Trial in Patients Receiving Peripheral Vascular Surgery

Conditions
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Peripheral Arterial Occlusive Disease

Intervention / Treatment
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* Dietary Supplement: Arginine
* Dietary Supplement: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: female or male patients receiving peripheral bypass surgery age between 55 and 75 years Exclusion Criteria: metabolic acidosis

Ages Eligible for Study
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Minimum Age: 55 Years
Maximum Age: 75 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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo<br>NaCl 0.9% intravenously for 24 hours after induction of anaesthesia | Dietary Supplement: Placebo<br>* NaCl 0.9% intravenously for 24h<br>|
| Active Comparator: Arginine<br>L-arginine-hydrochlorid (0.35 g/kg body weight) intravenously for 24 hours after induction of anaesthesia | Dietary Supplement: Arginine<br>* L-arginine-hydrochlorid (0.35 g/kg body weight) intravenously for 24 hours<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline in temperature gradient at 3h post-surgery | One temperature probe is attached to the index finger of the lying patients, a second probe at the radial side of the forearm, midway between elbow and the wrist. Temperature gradient is calculated by subtracting the value obtained at the fingertip from the forearm value and expressed in °C. | baseline and 3h post-surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline in Laser Doppler blood perfusion imaging at 1h | Perfusion values are expressed as arbitrary perfusion units. | baseline & 1h post-surgery | 
| Change from baseline in Laser Doppler blood perfusion imaging at 2h | Perfusion values are expressed as arbitrary perfusion units. | baseline & 2h post-surgery | 
| Change from baseline in Laser Doppler blood perfusion imaging at 3h | Perfusion values are expressed as arbitrary perfusion units. | baseline & 3h post-surgery | 
| Change from baseline in Laser Doppler blood perfusion imaging at 24h | Perfusion values are expressed as arbitrary perfusion units. | baseline & 24h post-surgery | 
| Change from baseline in Laser Doppler blood perfusion imaging at 48h | Perfusion values are expressed as arbitrary perfusion units. | baseline & 48h post-surgery | 
| Change from baseline in asymmetric dimethylarginine (ADMA) at 3h | Asymmetric dimethylarginine is measured by ELISA and expressed in µmol/l. | baseline & 3h post-surgery | 
| Change from baseline in asymmetric dimethylarginine (ADMA) at 24h | Asymmetric dimethylarginine is measured by ELISA and expressed in µmol/l. | baseline & 24h post-surgery | 
| Change from baseline in asymmetric dimethylarginine (ADMA) at 48h | Asymmetric dimethylarginine is measured by ELISA and expressed in µmol/l. | baseline & 48h post-surgery | 
| Change from baseline in plasma arginine concentration at 3h | L-arginine concentration is measured by HPLC and expressed in µmol/l. | baseline & 3h post-surgery | 
| Change from baseline in plasma arginine concentration at 24h | L-arginine concentration is measured by HPLC and expressed in µmol/l. | baseline & 24h post-surgery | 
| Change from baseline in plasma arginine concentration at 48h | L-arginine concentration is measured by HPLC and expressed in µmol/l. | baseline & 48h post-surgery | 
| Change from baseline in temperature gradient at 1h | One temperature probe is attached to the index finger of the lying patients, a second probe at the radial side of the forearm, midway between elbow and the wrist. Temperature gradient is calculated by subtracting the value obtained at the fingertip from the forearm value and expressed in °C. | baseline & 1h post-surgery | 
| Change from baseline in temperature gradient at 2h | One temperature probe is attached to the index finger of the lying patients, a second probe at the radial side of the forearm, midway between elbow and the wrist. Temperature gradient is calculated by subtracting the value obtained at the fingertip from the forearm value and expressed in °C. | baseline & 2h post-surgery | 
| Change from baseline in temperature gradient at 24h | One temperature probe is attached to the index finger of the lying patients, a second probe at the radial side of the forearm, midway between elbow and the wrist. Temperature gradient is calculated by subtracting the value obtained at the fingertip from the forearm value and expressed in °C. | baseline & 24h post-surgery | 
| Change from baseline in temperature gradient at 48h | One temperature probe is attached to the index finger of the lying patients, a second probe at the radial side of the forearm, midway between elbow and the wrist. Temperature gradient is calculated by subtracting the value obtained at the fingertip from the forearm value and expressed in °C. | baseline & 48h post-surgery |