Surface Landmarks and C-length as Predictors of Depth of Right IJV Catheter Insertion: A TEE-Guided Study

Study Overview
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Brief Summary
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The primary aim of the current study is to examine the accuracy of the C-distance or surface landmarks in determining the length of central venous catheter (CVC) that is required to place the catheter tip at the mid-superior vena cava (SCV) as confirmed by transesophageal echocardiography (TEE). A secondary aim is to derive an equation or formula to calculate the depth of the CVC that is required in order to have the catheter tip placed at the mid-SVC.

Detailed Description
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Before induction of anesthesia Two sets of measurements will be obtained for each participant before induction of anesthesia: Surface measurements: Three points will be placed on the skin using a non-erasable marker. Point A, at the apex of the triangle between the two heads of the sternomastoid. Point B, at the ipsilateral sternoclavicular joint. Point C, at the lower border of the right 2nd rib at its junction with the sternum. The distance between point A and point B and between point B and point C will be measured and added to each other to determine the catheter length expected to place the tip at the mid-SVC. Radiological measurements: On the plain posteroanterior (PA) chest X-ray (CXR), the distance from the tip of the transverse process of T1 to the tracheal bifurcation (C-length) will be measured. After induction of anesthesia After induction of anaesthesia, the TEE probe will be placed and a bicaval view will be displayed to visualize the right atrium-superior vena cava (RA-SVC) junction and the proximal (lower) part of the SVC at its entry into the right atrium (RA). The TEE probe will be manipulated to display the SVC as far as possible from its junction with the RA. The right internal jugular vein (IJV) will be cannulated under ultrasound guidance using the Seldinger technique. After puncture of the IJV a J-wire will be advanced through the trocar until the J-end of the guidewire is visualized at the RA-IJV junction via the TEE. The CVC catheter will be passed over the guidewire to the RA-SCV junction. The guidewire will be removed and the catheter will then be retracted under TEE guidance until the tip in visualized at 3.0 cm above the RA-SVC junction as measured with the TEE cursor. If the distal (upper) portion of the SVC could not be visualized, the catheter would be retracted for 3 cm as guided by the 1-cm gradations on the CVC. Post-operative After operation, plain PA CXR will be obtained at the intensive care unit (ICU) to verify the position of the CVC tip in relation to the carina. Statistical Analysis: The length of the catheter required to place the tip at the mid SVC will be regressed on the C-length or the surface distance to obtain a predictive equation. The accuracy of either equation will be assessed by estimation of the standard error of the estimate (SEest).

Official Title
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Evaluation of Surface Landmarks and C-length as Predictors of the Depth of Right Internal Jugular Venous Catheter Insertion: A Transesophageal Echocardiography-Guided Study

Conditions
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Echocardiography, Transesophageal, Catheterization, Central Venous, Anatomic Landmarks, Radiography

Intervention / Treatment
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* Procedure: Catheterization of internal jugular vein


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult subjects (age 18 years or older). Elective cardiac surgery. Echocardiography is indicated or recommended. Exclusion Criteria: Previous cardiothoracic or neck surgery. Previous radiotherapy on the neck or chest. Intra-thoracic or neck mass lesions. Deformity of the chest wall. Anomalies of the great vessels. Congenital heart disease.

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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Arms and Interventions

| Intervention/Treatment |
| --- |
|Procedure: Catheterization of internal jugular vein|The right internal jugular vein will be cannulated under transesophageal echocardiographic (TEE) guidance in order to place the catheter tip in the mid-SVC. The length of the catheter required to place the tip at the mid-SVC as guided by TEE will be regressed on the C-length or on the distance from the entry point to the surface point corresponding to the mid-SVC on the chest wall in order to obtain a predictive equation. The accuracy of either equation will be assessed by estimation of the standard error of the estimate (SEest).|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Accuracy of surface landmarks for prediction of CVC depth required to place the CVC tip at the mid-SVC. | Difference between actual length required to place the CVC tip at the mid-SVC as guided by TEE and the distance from the entry point to the surface point corresponding to the mid-SVC on the chest wall. | Outcome will be assessed at completion of catheterization procedure | 
| Accuracy of C-length for prediction of CVC depth required to place the CVC tip at the mid-SVC. | Difference between actual length required to place the CVC tip at the mid-SVC as guided by TEE and the C-length. | Outcome will be assessed at completion of catheterization procedure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Surface landmarks, C-length, Central venous catheterization, Internal jugular vein, Prediction, Accuracy