Diagnostic Value of Compression Ultrasound to Detect Acute Compartment Syndrome After Lower Limb Revascularisation

Study Overview
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Brief Summary
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Acute compartment syndrome (ACS) after revascularization for acute limb ischemia is a potentially limb-threatening condition and requires urgent fasciotomy. Compression ultrasound (CU) is an established method for measuring intravenous pressure in superficial veins and, for example, can determine central venous pressure in critically ill patients. In cadaver studies, compression ultrasound has been proven to correlate with invasive intra compartmental pressure (ICP) measurements. This study aims to determine CU's added diagnostic value compared to ICP in detecting ACS after revascularisation.

Detailed Description
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Acute compartment syndrome (ACS) after revascularization for acute limb ischemia is a potentially limb-threatening condition and requires urgent fasciotomy. It occurs when the tissue pressure within a closed muscle compartment exceeds the perfusion pressure and results in muscle and nerve ischemia. If clinically suspected, intra- compartmental pressure (ICP) is measured by inserting a needle into the area of ACS, usually the anterior tibial muscle compartment, while an attached pressure monitor records the pressure. This invasive diagnostic method is widely used as a standard with a sensitivity of 94% and specificity of 98%. Compression ultrasound (CU) is an established method for measuring intravenous pressure in superficial veins and, for example, can determine central venous pressure in critically ill patients. An ultrasound translucent probe measures the pressure applied on the skin surface with the ultrasound transducer. In cadaver studies, compression ultrasound has been proven to correlate with invasive ICP measurements. The elasticity ratio (ER, compartment diameter with and without external pressure) validated in a recently published animal model has a sensitivity of 94.4% and a specificity of 88.9% to diagnose a compartment syndrome properly. The first results in six trauma patients showed that the ER less than 10,5% of the anterior tibial compartment had a sensitivity of 95,8% and a specificity of 87,5% to an appropriate diagnosis of ACS. Thus, this non-invasive, low-cost, and secure diagnostic technique has not been validated in patients with ACS after revascularisation for acute lower limb ischemia yet has the potential to discriminate clinically suspected ACS sensitively. This study aims to determine CU's added diagnostic value compared to ICP in detecting ACS after revascularisation.

Official Title
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Diagnostic Value of Compression Ultrasound to Detect Acute Compartment Syndrome After Lower Limb Revascularisation

Conditions
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Compartment Syndrome of Leg

Intervention / Treatment
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* Diagnostic Test: Compression ultrasound examination


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical suspicion of acute compartment syndrome after revascularisation of lower limb Exclusion Criteria: Not fulfilling any of the inclusion criteria Patients refusing to participate

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: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Compression ultrasound<br>All recruited patients | Diagnostic Test: Compression ultrasound examination<br>* After successful revascularisation for acute ischemia and clinical suspicion of acute compartment syndrome, compression ultrasound (CU) will be performed in OR followed by standard intra-compartmental measurement. Two physicians will perform two subsequent measurements of the affected limb after revascularisation. The unaffected limb will be examined once to obtain baseline elasticity ratio values. All CU examinations will be documented in PACS (picture archiving and communication system) and evaluated after ICP measurement, and if necessary, fasciotomy is performed.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Elasticity ratio (ER) | Sensitivity and specificity of elasticity ratio measured by compression ultrasound for detecting high intra compartmental pressure | baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inter- and intra-rater reliability | Inter- and intra-rater reliability of compression ultrasound | baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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compartment syndrome, acute limb ischemia, intra compartmental pressure, compression ultrasound, vascular surgery, limb revascularisation