I just placed a 4 fr single lumn Picc line in a very obese pt. Used the ultrasound and sherlock. Pt is 400lbs and 5'8" tall. She needs 2-3 weeks IV Ancef. I had a very hard time with the initial measurements as she has so much breast and chest tissue. I could not even palpate any bone, ribs etc. in the chest and she has no neck, her neck fat folds over her chest. I measured it too long on purpose, probablly because the pt stated that the last Picc she had was too short and she had to have it replaced. I had to get several CXR's before the Optimal placement was obtained. The tip was in too far. We finally got a pretty good look with an oblique. I ended up having to pull it back twice to 9 cm! I can't remember ever doing that! The insertion was easy except that the sherlock would not pick up the signal in the chest. I had to rely on my old instincts from before there were such devices. She had no 'rushing' sound in ear/neck during flushing and insertion was smooth, with good and easy blood return. Does anyone have any advice for initial measument for obese pts? I did notice that her heart seemed very high in the chest upon XRay. Maybe due to the huge belly pressing it up? Any way it is working great with the tip in the CAJ!