Patent ID: 8512256

Claim:
A method of locating a tip of a central venous catheter having a portion disposed within the superior vena cava, the catheter comprising a distal pair of electrodes and a proximal pair of electrodes spaced longitudinally from the distal pair of electrodes, the method comprising: obtaining a distal electrical signal from the distal pair of electrodes; generating a first P wave from the distal signal; obtaining a proximal electrical signal from the proximal pair of electrodes; generating a second P wave from the proximal signal; comparing the first and second P waves; obtaining a reference electrical signal in the superior vena cava; generating a reference P wave from the reference electrical signal; comparing the reference P wave with at least one of the first and second P waves; and determining a location of the tip of the central venous catheter based on the comparison of the first and second P waves and the comparison of the reference P wave with at least one of the first and second P waves.