Invasive Medical Devices Including Magnetic Region And Systems And Methods
Devices, systems, and methods are described including an invasive medical device with a magnetic region. The magnetic region can include a discontinuity in the magnetic region providing a diameter transition, a plurality of spaced magnetic regions can be provided or the magnetic regions can be encoded with data. Systems and methods are described that include ways to read the data.
1 . An invasive medical device for insertion into a patient, the device comprising:
an elongate shaft having a diameter, an outer surface, a distal tip, and a proximal end, the diameter of the elongate shaft sized to be inserted within an intravenous catheter, at least a portion of the elongate shaft having a first magnetic region and a discontinuity in the first magnetic region providing a diameter transition such that the shaft includes an increased diameter region.
2 . The invasive medical device of claim 1 , wherein medical device is selected from a guidewire, a catheter introducer, a stylet and a hypodermic needle, and the discontinuity is selected from the group consisting of a layer ferromagnetic metal, a layer of paramagnetic metal, a spot weld of magnetic metal, a ferrule and combinations thereof.
3 . The invasive medical device of claim 2 , wherein the shaft is disposed within intravenous catheter tubing.
4 . The invasive medical device of claim 3 , wherein the invasive medical device comprises a hypodermic needle.
5 . The invasive medical device of claim 4 , wherein the discontinuity comprises a layer of ferromagnetic metal or a layer of paramagnetic metal that increases the diameter of the shaft of the needle.
6 . The invasive medical device of claim 4 , wherein the discontinuity comprises a ferrule over the shaft of the needle, and the ferrule has an outer diameter greater than the diameter of the shaft of the needle.
7 . The invasive medical device of claim 4 , wherein the discontinuity comprises a magnetic adhesive on the outer surface of the needle.
8 . The medical device according to claim 7 , wherein the adhesive includes an additive selected from a paramagnetic additive, a ferromagnetic additive and combinations thereof.
9 . The medical device according to claim 8 , wherein the additive includes a component selected from the group consisting of powdered iron, magnetic iron oxide, magnetic titanium oxide, magnetic powdered steel, and a magnetic iron alloy, and mixtures thereof.
10 . The medical device according to claim 9 , wherein the magnetic iron alloy includes one or more of nickel, zinc, and copper.
11 . The medical device according to claim 10 , wherein the additive further comprises a component selected from chromium, magnesium, molybdenum and combinations thereof.
12 . The invasive medical device of claim 4 , wherein the needle comprises martensitic stainless steel.
13 . The invasive medical device of claim 4 , wherein the needle is part of a needle subassembly further including a needle hub mounted to the proximal end of the needle, and the intravenous catheter tubing is part of a catheter adapter subassembly.
14 . The invasive medical device of claim 13 , the catheter adapter subassembly including catheter tubing and a catheter adapter body, wherein the shaft is slidably engaged with the intravenous catheter tubing.
15 . The invasive medical device of claim 14 , wherein the catheter adapter subassembly further comprises a magnetic feature.
16 . A system for determining relative position of a needle comprising the invasive medical device of claim 15 and magnetometers positioned with respect to the first magnetic region and the magnetic feature.
17 . An invasive medical device for insertion into a patient, the device comprising:
a hypodermic needle including an elongate shaft having a diameter, an outer surface, a distal tip, and a proximal end, the diameter of the elongate shaft sized to be inserted within an intravenous catheter, at least a portion of the elongate shaft having a first magnetic region and a discontinuity in the first magnetic region providing a diameter transition such that the shaft includes an increased diameter region.
18 . The invasive medical device of claim 17 , wherein medical device is selected from a guidewire, a catheter introducer, a stylet and a hypodermic needle, and the discontinuity is selected from the group consisting of a layer ferromagnetic metal, a layer of paramagnetic metal, a spot weld of magnetic metal, a ferrule and combinations thereof.
19 . The invasive medical device of claim 18 , wherein the shaft is disposed within intravenous catheter tubing.
20 . The invasive medical device of claim 19 , wherein the needle is part of a needle subassembly further including a needle hub mounted to the proximal end of the needle, and the intravenous catheter tubing is part of a catheter adapter subassembly.