title: Depth of insertion of right internal jugular central venous catheter: Comparison of topographic and formula methods.
abstract: BACKGROUND
  Central venous catheters (CVCs) are inserted in many critically ill patients, but there is no gold standard in estimating their approximate depth of insertion. Many techniques have been described in literature. In this study, we compare the topographic method with the standard formula technique.
  
  
  METHODS
  260 patients, in whom central venous catheterization was warranted, were randomly assigned to either topographic method or formula method (130 in each group). The position of the CVC tip in relation to carina was measured on a postprocedure chest X-ray. The primary endpoint was the need for catheter repositioning.
  
  
  RESULTS
  The majority of the CVCs tips positioned by the formula method were situated below the carina, and 68% of these catheters required repositioning after obtaining postprocedure chest X-ray (P < 0.001).
  
  
  CONCLUSIONS
  The topographic method is superior to formula approach in estimating the depth of insertion of right internal jugular CVCs.
authors.affiliation: Department of Anesthesiology, Bangalore Medical College and Research Institute, Bengaluru, Karnataka, India.
authors.forename: M
authors.initials: M
authors.lastname: Vinay
authors.affiliation: Department of Anesthesiology, MS Ramaiah Medical College and Hospitals, Bengaluru, Karnataka, India.
authors.forename: C A
authors.initials: CA
authors.lastname: Tejesh
keywords: Central venous catheter tip; formula method; topographic method