title: Ultrasound confirmation of central venous catheter position via a right supraclavicular fossa view using a microconvex probe: an observational pilot study.
abstract: BACKGROUND
  Visualisation of a central venous catheter (CVC) with ultrasound is restricted to the internal jugular vein (IJV). CVC tip position is confirmed by chest radiography, intracardiac ECG or transoesophageal/transthoracic echocardiography (TEE/TTE).
  
  
  OBJECTIVE
  We explored the feasibility, safety and accuracy of a right supraclavicular view for visualisation of the lower superior vena cava (SVC) and the right pulmonary artery (RPA) as an ultrasound landmark for real-time ultrasound-guided CVC tip positioning via the right IJV. Ultrasound was then compared with chest radiography.
  
  
  METHODS
  An observational pilot study.
  
  
  METHODS
  Bonn, University Hospital, Germany. From July to October 2012.
  
  
  METHODS
  Fifty-one patients scheduled for elective surgery. Reasons for exclusion were emergency procedure, thrombosis or small IJV lumen and mechanical obstacle to guidewire advancement.
  
  
  METHODS
  In 48 patients, CVC insertion via the right IJV and progress of the guidewire into the lower SVC were continuously guided by an ultrasound transducer in the right supraclavicular fossa.
  
  
  METHODS
  CVC tip position in lower SVC and tip-to-carina distance were assessed with chest radiography as a reference method and additionally with TEE in cardiothoracic patients. Insertion depth was compared with intracardiac ECG and body-height formula.
  
  
  RESULTS
  The guidewire tip was seen in the SVC of all patients. In four patients, the tip was not visible in proximity of the RPA. Chest radiography and TEE confirmed CVC tip position in the lower SVC (zone A). Bland-Altman analysis revealed an average of difference of 1.6 cm for ultrasound versus ECG (95% limit of agreement -2 to 5 cm) and an average of difference of 1 cm for ultrasound versus body-height formula (95% limit of agreement -2 to 4 cm).
  
  
  CONCLUSIONS
  Ultrasound via a right supraclavicular view is a feasible, well tolerated and accurate approach and should be further explored. Chest radiography confirmed CVC position in the lower SVC.
authors.affiliation: From the Department of Anesthesiology and Intensive Care Medicine (S-CK, IH, GB, AH, SW, PK), and Department of Radiology (AS), University Hospital Bonn, Bonn, Germany *Both Se-Chan Kim and Ingo Heinze contributed equally to this work.
authors.forename: Se-Chan
authors.initials: SC
authors.lastname: Kim
authors.forename: Ingo
authors.initials: I
authors.lastname: Heinze
authors.forename: Alexandra
authors.initials: A
authors.lastname: Schmiedel
authors.forename: Georg
authors.initials: G
authors.lastname: Baumgarten
authors.forename: Pascal
authors.initials: P
authors.lastname: Knuefermann
authors.forename: Andreas
authors.initials: A
authors.lastname: Hoeft
authors.forename: Stefan
authors.initials: S
authors.lastname: Weber
mesh_terms: D000368:Aged; D002405:Catheterization, Central Venous / Q000295:instrumentation / Q000379:methods*; D062905:Central Venous Catheters; D002968:Clavicle / Q000098:blood supply / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D018084:Ultrasonography, Interventional / Q000295:instrumentation / Q000379:methods*; D014683:Vena Cava, Superior / Q000000981:diagnostic imaging