Metal Contamination After Minimally Invasive Repair of Pectus Excavatum (MIRPE)

Study Overview
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Brief Summary
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The purpose of this study is to determine whether there is a metal wear debris after minimally invasive repair of pectus excavatum and if there's a clinical relevance. Our hypothesis is that the metal bar after minimally invasive repair of pectus excavatum leads to a locally and systemic immune reaction due to elevated metal contamination.

Official Title
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Examination of Metal Contamination After Minimally Invasive Repair of Pectus Excavatum (MIRPE) and the Clinical Relevance

Conditions
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Congenital Funnel Chest

Intervention / Treatment
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* Procedure: minimally invasive repair of pectus excavatum


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: MIRPE Exclusion Criteria: none

Ages Eligible for Study
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Minimum Age: 12 Years
Maximum Age: 45 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with MIRPE<br>first minimally invasive repair of pectus excavatum | Procedure: minimally invasive repair of pectus excavatum<br>* substernal insertion of a metal bar<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change of mean chromium values in blood (µg/l) | measurement of: 1) chromium in blood (in µg/l) at the time points: pre implantation 4 weeks after implantation (to see change to baseline) 1 year after implantation (to see change to baseline) 2 years after implantation (to see change to baseline) explantation (usually 3 years after implantation; to see change to baseline) 6-12 months after explantation (to see change to explantation) We will compare the mean metal values at each time point post implantation with the mean metal values pre implantation. Clinical data like body weight etc. won't be relevant for the analysis. | 4 years | 
| change of mean chromium values in urine (µg/l) | measurement of: 2) chromium in urine (in µg/l) at the time points: pre implantation 4 weeks after implantation (to see change to baseline) 1 year after implantation (to see change to baseline) 2 years after implantation (to see change to baseline) explantation (usually 3 years after implantation; to see change to baseline) 6-12 months after explantation (to see change to explantation) We will compare the mean metal values at each time point post implantation with the mean metal values pre implantation. Clinical data like body weight etc. won't be relevant for the analysis. | 4 years | 
| change of mean chromium values in tissue (µg/g) | measurement of: 3) chromium in tissue (in µg/g) at the time points: implantation explantation (usually 3 years after implantation; to see change to baseline) We will compare the mean metal values at explantation with the mean metal values before implantation. Clinical data like body weight etc. won't be relevant for the analysis. | 3 years | 
| change of mean nickel values in blood (µg/l) | measurement of: 4) nickel in blood (in µg/l) at the time points: pre implantation 4 weeks after implantation (to see change to baseline) 1 year after implantation (to see change to baseline) 2 years after implantation (to see change to baseline) explantation (usually 3 years after implantation; to see change to baseline) 6-12 months after explantation (to see change to explantation) We will compare the mean metal values at each time point post implantation with the mean metal values pre implantation. Clinical data like body weight etc. won't be relevant for the analysis. | 4 years | 
| change of mean nickel values in urine (µg/l) | measurement of: 5) nickel in urine (in µg/l) at the time points: pre implantation 4 weeks after implantation (to see change to baseline) 1 year after implantation (to see change to baseline) 2 years after implantation (to see change to baseline) explantation (usually 3 years after implantation; to see change to baseline) 6-12 months after explantation (to see change to explantation) We will compare the mean metal values at each time point post implantation with the mean metal values pre implantation. Clinical data like body weight etc. won't be relevant for the analysis. | 4 years | 
| change of mean nickel values in tissue (µg/g) | measurement of: 6) nickel in tissue (in µg/g) at the time points: implantation explantation (usually 3 years after implantation; to see change to baseline) We will compare the mean metal values at explantation with the mean metal values before implantation. Clinical data like body weight etc. won't be relevant for the analysis. | 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Observation of clinical reactions in correlation with elevated metal values | observation (description) of clinical symptoms of a metal allergy like local rash lassitude chest pain tachycardia Nausea pleural effusion for the time the bar is in place (3 years) and the metal values are evaluated. -> Then compare the mean metal values (see above) with the baseline and the other patients (with and/or without problems) No records when the patients don't have any problems. | 4 years |