This experimental protocol has been reviewed and approved by our hospital&#8217;s institutional review board (IRB) and follows all guidelines set forth by our institution&#8217;s human research ethics committee.
1. Identify the Fascia of the Anterior Compartment of the Leg
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	<li>Identify a starting site for the ultrasound probe. Place the probe directly over the anterior compartment, just lateral to the tibial crest and one handbreadth distal to the tibial tubercle.</li>
	<li>Identify th...

<ol>
	<li>Ulmer, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+clinical+diagnosis+of+compartment+syndrome+of+the+lower+leg:+are+clinical+findings+predictive+of+the+disorder?.">The clinical diagnosis of compartment syndrome of the lower leg: are clinical findings predictive of the disorder?.</a> Journal of Orthopaedic Trauma. 16 (8), 572-577 (2002).</li><li>Whitesides, T. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tissue+pressure+measurements+as+a+determinant+for+the+need+of+fasciotomy.">Tissue pressure measurements as a determinant for the need of fasciotomy.</a> Clinical Orthopaedics and Related Research. 113, 43-51 (1975).</li><li>McQueen, M. M., Court-Brown, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Compartment+monitoring+in+tibial+fractures:+the+pressure+threshold+for+decompression.">Compartment monitoring in tibial fractures: the pressure threshold for decompression.</a> The Journal of Bone and Joint Surgery. British Volume. 78 (1), 99-104 (1996).</li><li>McQueen, M. M., Christie, J., Court-Brown, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Compartment+pressures+after+intramedullary+nailing+of+the+tibia.">Compartment pressures after intramedullary nailing of the tibia.</a> The Journal of Bone and Joint Surgery. British Volume. 72 (3), 395-397 (1990).</li><li>Masquelet, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acute+compartment+syndrome+of+the+leg:+pressure+measurement+and+fasciotomy.">Acute compartment syndrome of the leg: pressure measurement and fasciotomy.</a> Orthopaedics &amp; Traumatology: Surgery &amp; Research. 96 (8), 913-917 (2010).</li><li>McQueen, M. M., Duckworth, A. D., Aitken, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+estimated+sensitivity+and+specificity+of+compartment+pressure+monitoring+for+acute+compartment+syndrome.">The estimated sensitivity and specificity of compartment pressure monitoring for acute compartment syndrome.</a> Journal of Bone and Joint Surgery. 95 (8), 673-677 (2013).</li><li>Whitney, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Do+one-time+intracompartmental+pressure+measurements+have+a+high+false-positive+rate+in+diagnosing+compartment+syndrome?.">Do one-time intracompartmental pressure measurements have a high false-positive rate in diagnosing compartment syndrome?.</a> Journal of Trauma and Acute Care Surgery. 76 (2), 479-483 (2014).</li><li>Sellei, R. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+elevated+compartment+pressures+by+pressure-related+ultrasound:+a+cadaveric+model.">Assessment of elevated compartment pressures by pressure-related ultrasound: a cadaveric model.</a> European Journal of Trauma and Emergency Surgery. 41 (6), 639-645 (2015).</li><li>Sellei, R. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Compartment+elasticity+measured+by+pressure-related+ultrasound+to+determine+patients+&#8220;at+risk&#8221;+for+compartment+syndrome:+an+experimental+in+vitro+study.">Compartment elasticity measured by pressure-related ultrasound to determine patients &#8220;at risk&#8221; for compartment syndrome: an experimental in vitro study.</a> Patient Safety in Surgery. 9 (1), 4 (2015).</li><li>Bloch, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Compression+sonography+for+non-invasive+measurement+of+lower+leg+compartment+pressure+in+an+animal+model.&amp;#34;.">Compression sonography for non-invasive measurement of lower leg compartment pressure in an animal model.&amp;#34;.</a> Injury. 49 (3), 532-537 (2018).</li><li>Marmor, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+standard+musculoskeletal+ultrasound+to+determine+the+need+for+fasciotomy+in+an+elevated+muscle+compartment+pressure+cadaver+leg+model.">Use of standard musculoskeletal ultrasound to determine the need for fasciotomy in an elevated muscle compartment pressure cadaver leg model.</a> Injury. , (2019).</li></ol>

This article demonstrates a novel, clinically applicable technique for the non-invasive measurement of intra-compartmental pressures in the leg using an ultrasound coupled with a pressure sensor. This technique only requires a hand-held ultrasound and a commercially available pressure sensing transducer. It is quick and easy to perform and is well tolerated by patients. The entire diagnostic procedure can be performed in under 5 min with no additional resources. The calculated delta CFFP may then be used in conjunction w...

The purpose of this novel protocol is to evaluate the intra-compartmental pressure of the leg in a non-invasive way by using an ultrasound transducer coupled with a pressure sensor. Compartment syndrome is a well-known complication in musculoskeletal trauma and is the result of elevated intra-compartmental pressures which compromise the perfusion of tissues leading to irreversible ischemic injury if not intervened upon. Its diagnosis is primarily based on clinical exam. Unfortunately, clinical exam alone has been shown to have poor sensitivity and specificity in the diagnosis of compartment syndrome1. Invasive intra-compartmental pressure measuring by needle manometry is commonly used in the assessment of compartment syndrome2,3,4. The disadvantage of needle manometry is that it is an invasive procedure, being quite uncomfortable for the patient and not amenable to serial measurements. Furthermore, invasive intra-compartmental pressure measuring measurement is not routinely performed by some surgeons due to considerable disagreement over the appropriate threshold pressure for diagnosis of ACS and the high (35%) false positive rate and variability of a single invasive measurement5,6,7.
It has been previously demonstrated in artificial, animal, and human cadaver models that a rise in the intra-compartmental pressure results in a decreased elasticity of the fascia overlying the anterior compartment suggesting a correlation between the intra-compartmental pressure and compliance of the facial compartment as measured by ultrasound8,9,10. Further work has described using the pressure required to flatten the fascia of the anterior compartment as measured by ultrasound (Compartment Fascia Flattening Pressure [CFFP]) as a surrogate measure of the intra-compartmental pressure11. The anterior compartment fascia can be readily visualized with standard ultrasonography and, with the addition of a pressure sensor to the probe, CFFPs can be easily and reliably measured. This protocol offers a non-invasive diagnostic alternative for evaluating intra-compartmental pressures and can be performed quickly and serially with little to no patient discomfort.

<table>
<tbody>
<tr>
<td>Pressure sensor: Venous pressure measurement device</td>
<td>Vein press</td>
<td>VP 2014</td>
<td>A peripheral venous measuring device used in conjuction with an ultrasound to measure peripheral venous pressure.</td>
</tr>
<tr>
<td>Ultrasound probe: Vscan Extend R2 Dual Probe DICOM Base Package</td>
<td>GE Healthcare</td>
<td>H8038VP</td>
<td>Any ultrasound probe will be sufficent for this test. Using the narrow tranducer will function best when coupled to the pressure sensor</td>
</tr>
</tbody>
</table>

a novel non-invasive method for the detection of elevated intra-compartmental pressures of the leg

Acute Compartment Syndrome is a devastating consequence of musculoskeletal trauma. Currently the diagnosis is based on clinical signs and symptoms, and while adjuncts such as invasive intra-compartmental pressure measurements are often used to corroborate the physical exam findings, there remains no reliable objective test to aid in the decision to perform a decompressive fasciotomy. In a cadaver model of compartment syndrome, an ultrasound (US) based method has been shown to be a reliable measurement of increased intra-compartmental pressure. An absolute pressure of &#62;100 mbar or a difference of 50 mbar in the CFFP between the legs can be considered pathologic. Using an ultrasound transducer, coupled with a pressure sensor, the pressure needed to flatten the superficial fascia of the anterior compartment of lower legs (Compartment Fascia Flattening Pressure [CFFP]) can be measured. The CFFP of the injured leg is compared to the CFFP of the uninjured leg. This US measured index can then serve as an adjunct to the physical exam in evaluating injured lower extremities and assessing the need for decompressive fasciotomy. The advantages of this protocol include: being a non-invasive method and an easily reproducible technique.

This technique has been used to measure 10 consecutive patients with injured legs without evidence of compartment syndrome and 3 patients with a clinical diagnosis of compartment syndrome necessitating decompressive fasciotomies. The average delta CFFP for patients without compartment syndrome was 10.7 &#177; 10.6 mbar compared to 157 &#177; 51.7 mbar for patients with compartment syndrome and single-tailed t-test identified the differences in pressures between the groups as being statistically significant (P &#60; 0.02)...

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A Novel Non-invasive Method for the Detection of Elevated Intra-compartmental Pressures of the Leg

An ultrasound probe coupled with a pressure sensor is used to assess the intra-compartmental pressure of the leg by directly measuring the compartment fascia flattening pressure (CFFP). This non-invasive protocol will provide reliable assessment of the pressure inside the anterior muscular compartment of the lower leg.

Acute Compartment Syndrome is a devastating consequence of musculoskeletal trauma. Currently the diagnosis is based on clinical signs and symptoms, and ...

This protocol is uniquely significant because it's a non-invasive means of assessing intra-compartmental pressures in the leg. This can be important when evaluating an injured extremity, which may be at risk for compartment syndrome, a limb-threatening condition. As intra-compartmental pressures rise, the perfusion of the structures within the compartment decreases, leading to an ischemic insult.If elevated pressures are not identified and treated quickly, the compartment dies, resulting in permanent disability. The primary advantage of this technique is its non-invasiveness. Currently, the only means by which to measure intra-compartmental pressure is by inserting a large-bore needle equipped with a pressure gauge into the leg compartment.While reliable, this technique is quite uncomfortable to the patient and is not suitable for performing serial measurements. For someone first trying this technique, I would recommend that they first practice the technique on a volunteer. Learning the amount of pressure to apply and interpreting the ultrasound images can be difficult at first.To begin this procedure, identify a starting site for the ultrasound probe. Place the probe directly over the anterior compartment, just lateral to the tibial crest and one hand breadth distal to the tibial tubercle. Next, identify the fascia, which is the bright white strip just below the subcutaneous tissue on the ultrasound.Move the probe until the fascia is seen at the point where it attaches to the tibial crest. Note the geometry of the fascia. With minimal applied, this should be a convex shape.Once the fascia of the anterior compartment is identified, apply slow and steady pressure to the ultrasound probe until the fascia changes shape from convex to completely flat. Make several attempts, including passing the flattening point to produce a concave shape in an effort to gently hone in on the exact compartment fascia flattening pressure. Once the anterior compartment fascia is perfectly flat, record the pressure sensor measurement.Repeat the CFFP measurement two more times. Record an average, all three pressures, to define the final CFFP of the injured leg. First, measure and record the CFFP in the contralateral leg in the same manner previously described.Calculate the delta CFFP by taking the difference between the CFFP of the injured leg from the CFFP of the well leg. In this study, a novel, clinically applicable technique for the non-invasive measurement of intra-compartmental pressures in the leg is demonstrated using an ultrasound coupled with a pressure sensor. This technique has been used to measure 10 consecutive patients with injured legs without evidence of compartment syndrome, and three patients with a clinical diagnosis of compartment syndrome, necessitating decompressive fasciotomies.The average delta CFFP for patients without compartment syndrome is approximately 10.7 millibar, compared to approximately 157 millibar for patients with compartment syndrome. A single-tailed T-test identified the differences in pressures between the groups as being statistically significant. When performing this technique, it is important to identify the pressure at the exact point when the fascia changes from convex to completely flat.To best facilitate this, it is helpful to have an assistant available to read the pressure while the person performing the technique maintains their focus on the ultrasound. Once the fascia changes from convex to flat, the person performing the test can call out pressure, signaling the assistant to record the pressure reading. After this diagnostic test is performed, the results can be compared against the gold standard for assessing intra-compartmental pressures, which is needle manometry.The most commonly used device for this is the Stryker quick pressure monitor set.

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8.5K visualizações.  University of California, San Francisco. Este protocolo é excepcionalmente significativo porque é um meio não invasivo de avaliar pressões intra-compartimentais na perna. Isso pode ser importante ao avaliar uma extremidade ferida, que pode estar em risco de síndrome compartimental, uma condição ameaçadora de membros. À medida que as pressões intra-compartimentais aumentam, a perfusão das estruturas dentro do compartimento diminui, levando a um insulto isquêmico.Se pressões elevadas não forem identificadas e trat...