title: Accurate nonfluoroscopic guidance and tip location of peripherally inserted central catheters using a conductance guidewire system.
abstract: BACKGROUND
  Bedside placement of peripherally inserted central catheters (PICCs) may result in navigation to undesirable locations, such as the contralateral innominate or jugular vein, instead of the superior vena cava or right atrium. Although some guidance and tip location tools exist, they have inherent limitations because of reliance on physiological measures (eg, chest landmarks, electrocardiogram, etc), instead of anatomical assessment (ie, geometric changes in the vasculature). In this study, an accurate, anatomically based, non-X-ray guidance tool placed on a novel 0.035" conductance guidewire (CGW) is validated for PICC navigation and tip location.
  
  
  METHODS
  The CGW system uses electrical conductance recordings to assess changes in vessel cross-sectional area to guide navigation of the PICC tip. Conductance rises and oscillates when going in the correct direction to the superior vena cava/right atrium, but drops when going in the incorrect direction away from the heart. Bench and in vivo studies in six swine were used to confirm the accuracy and repeatability of the PICC placement at various anatomical locations. The PICC tip location was confirmed by direct visualization vs the desired location.
  
  
  RESULTS
  CGW PICC guidance was highly accurate and repeatable with virtually no difference between actual and desired catheter tip location. The difference between the CGW PICC location vs the desired target was -0.07 ± 0.07 cm (6.6% error) on the bench and 0.04 ± 0.10 cm (5% error) in vivo. No complications or adverse events occurred during CGW usage.
  
  
  CONCLUSIONS
  The CGW provides an anatomically based, reproducible, and clinically significant method for PICC navigation and tip location that can improve accuracy, decrease the wait time prior to therapy delivery, decrease cost, and minimize the need for X-ray. These findings warrant clinical evaluation of this navigation tool for PICC line placement.
authors.affiliation: Department of Biomedical Engineering, Indiana University-Purdue University Indianapolis, Indianapolis, Ind.
authors.forename: Mark C
authors.initials: MC
authors.lastname: Svendsen
authors.affiliation: Department of Biomedical Engineering, Indiana University-Purdue University Indianapolis, Indianapolis, Ind.
authors.forename: David
authors.initials: D
authors.lastname: Birrer
authors.affiliation: Department of Biomedical Engineering, Indiana University-Purdue University Indianapolis, Indianapolis, Ind.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Jansen
authors.affiliation: Indiana Institute for Biomedical Imaging Sciences, Indiana University School of Medicine, Indianapolis, Ind.
authors.forename: Shawn D
authors.initials: SD
authors.lastname: Teague
authors.affiliation: Department of Biomedical Engineering, Indiana University-Purdue University Indianapolis, Indianapolis, Ind.
authors.forename: Bill
authors.initials: B
authors.lastname: Combs
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minn.
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Schears
authors.affiliation: Department of Biomedical Engineering, Indiana University-Purdue University Indianapolis, Indianapolis, Ind; Department of Cellular and Integrative Physiology, Indiana University-Purdue University Indianapolis, Indianapolis, Ind; Department of Surgery, Indiana University-Purdue University Indianapolis, Indianapolis, Ind. Electronic address: gkassab@iupui.edu.
authors.forename: Ghassan S
authors.initials: GS
authors.lastname: Kassab