Catheter Tip Positioning Method

• US 20100317981A1
• Filed: 06/14/2010
• Published: 12/16/2010
• Est. Priority Date: 06/12/2009
• Status: Active Grant

• Current Assignee: BARD Access Systems Incorporated (Becton, Dickinson & Co)
• Original Assignee: Romedex International SRL
• Inventors: Grunwald, Sorin
• Granted Patent: US 9,339,206 B2
• Time in Patent Office: Days
• US Class Current: 600/509
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/065 Determining position of the probe employing exclusively positioning means located on or in the probe, e.g. using position sensors arranged on the probe
• CPC Class Codes: A61B 5/283 Invasive
• CPC Class Codes: A61B 5/316 Modalities, i.e. specific diagnostic methods
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/726 using Wavelet transforms
• CPC Class Codes: A61M 2039/1077 Adapters, e.g. couplings adapting a connector to one or several other connectors
• CPC Class Codes: A61M 2039/1083 having a plurality of female connectors, e.g. Luer connectors
• CPC Class Codes: A61M 2039/1088 having a plurality of male connectors, e.g. Luer connectors
• CPC Class Codes: A61M 25/0014 Connecting a tube to a hub

Abstract

A computer-based method for positioning an endovascular device in or near the heart using electrocardiogram (ECG) signals is provided. The computer-based method includes receiving an endovascular ECG signal, associated with an endovascular device, including a plurality of waveforms, each waveform having at least a P-wave component, processing the endovascular ECG signal, over a plurality of predetermined time periods, to calculate a P-wave amplitude and a spectral power for each predetermined time period, determining a maximum P-wave amplitude from the plurality of P-wave amplitudes, and an associated maximum spectral power from the plurality of spectral powers, associating the maximum P-wave amplitude and the maximum spectral power with a predetermined location in or near the heart, calculating a location of the endovascular device, for each predetermined time period, based on a ratio of the P-wave amplitude to the maximum P-wave amplitude and a ratio of the spectral power to the maximum spectral power, and displaying the location of the endovascular device to a user.

Claims

1. A computer-based method for positioning an endovascular device in or near the heart using electrocardiogram (ECG) signals, comprising:

receiving an endovascular ECG signal, associated with an endovascular device, including a plurality of waveforms, each waveform having at least a P-wave component;

processing the endovascular ECG signal, over a plurality of predetermined time periods, to calculate a P-wave amplitude and a spectral power for each predetermined time period;

determining a maximum P-wave amplitude from the plurality of P-wave amplitudes, and an associated maximum spectral power from the plurality of spectral powers;

associating the maximum P-wave amplitude and the maximum spectral power with a predetermined location in or near the heart;

calculating a location of the endovascular device, for each predetermined time period, based on a ratio of the P-wave amplitude to the maximum P-wave amplitude and a ratio of the spectral power to the maximum spectral power; and

displaying the location of the endovascular device to a user.

2. The computer-based method according to claim 1, wherein the P-wave amplitude is a peak-to-peak value, and the maximum P-wave amplitude is a peak-to-peak value.

3. The computer-based method according to claim 2, wherein said processing the ECG signal includes determining a polarity for each P-wave amplitude, and said determining the location of the endovascular device is also based on the P-wave polarity for each predetermined time period.

4. The computer-based method according to claim 3, wherein the predetermined location is the caval-atrial junction.

5. The computer-based method according to claim 4, wherein the location of the endovascular device is the upper superior vena cava if the ratio of the P-wave amplitude to the maximum P-wave amplitude is less than 0.4, the ratio of the spectral power to the maximum spectral power is less than 0.4, and the P-wave polarity is unipolar.

6. The computer-based method according to claim 5, wherein the location of the endovascular device is the lower third of the superior vena cava if the ratio of the P-wave amplitude to the maximum P-wave amplitude is between 0.4 and 0.6, the ratio of the spectral power to the maximum spectral power is between 0.4 and 0.6, and the P-wave polarity is unipolar.

7. The computer-based method according to claim 6, wherein the location of the endovascular device is the caval-atrial junction if the ratio of the P-wave amplitude to the maximum P-wave amplitude is greater than 0.9, the ratio of the spectral power to the maximum spectral power is greater than 0.9, and the P-wave amplitude is greater than the R-wave amplitude.

8. The computer-based method according to claim 7, wherein the location of the endovascular device is the right atrium if the ratio of the spectral power to the maximum spectral power is between 0.6 and 0.9, and the P-wave polarity is bipolar.

9. The computer-based method according to claim 8, wherein the location of the endovascular device is the upper third of the inferior vena cava if the ratio of the P-wave amplitude to the maximum P-wave amplitude is between 0.4 and 0.6, the ratio of the spectral power to the maximum spectral power is between 0.4 and 0.6, and the P-wave polarity is unipolar with reversed polarity.

10. The computer-based method according to claim 4, wherein the endovascular device is a central venous catheter coupled to an adapter that includes an electrode in contact with a saline solution column exposed to the tip of the catheter, and the endovascular ECG signal is based on an electrical signal measured by the electrode.

11. The computer-based method according to claim 10, further comprising:

simultaneously receiving a skin ECG signal, associated with a skin ECG lead, including a plurality of waveforms, each waveform having at least a P-wave component;

processing the skin ECG signal, over the plurality of predetermined time periods, to calculate a skin P-wave amplitude and a skin spectral power for each predetermined time period;

determining a maximum skin P-wave amplitude from the plurality of skin P-wave amplitudes, and an associated maximum skin spectral power from the plurality of skin spectral powers;

associating the maximum skin P-wave amplitude and the maximum skin spectral power with the predetermined location in or near the heart; and

calculating the location of the endovascular device, for each predetermined time period, based on a ratio of the endovascular P-wave amplitude to the maximum skin P-wave amplitude and a ratio of the endovascular spectral power to the maximum skin spectral power.

12. The computer-based method according to claim 11, wherein the location of the endovascular device is the upper superior vena cava if the ratio of the endovascular P-wave amplitude to the maximum skin P-wave amplitude is between 0.9 and 1.2, the ratio of the endovascular spectral power to the maximum skin spectral power is between 0.9 and 1.2, and the P-wave polarity is unipolar.

13. The computer-based method according to claim 12, wherein the location of the endovascular device is the lower third of the superior vena cava if the ratio of the endovascular P-wave amplitude to the maximum skin P-wave amplitude is between 1.5 and 2.0, the ratio of the endovascular spectral power to the maximum skin spectral power is between 1.5 and 2.0, and the P-wave polarity is unipolar.

14. The computer-based method according to claim 13, wherein the location of the endovascular device is the caval-atrial junction if the ratio of the endovascular P-wave amplitude to the maximum skin P-wave amplitude is greater than 2.5, the ratio of the spectral power to the maximum spectral power is greater than 2.59, and the endovascular P-wave amplitude is greater than the endovascular R-wave amplitude.

15. The computer-based method according to claim 14, wherein the location of the endovascular device is the right atrium if the ratio of the endovascular spectral power to the maximum skin spectral power is between 2.0 and 2.5, and the endovascular P-wave polarity is bipolar.

16. The computer-based method according to claim 15, wherein the location of the endovascular device is the upper third of the inferior vena cava if the ratio of the endovascular P-wave amplitude to the maximum skin P-wave amplitude is between 0.9 and 1.2, the ratio of the endovascular spectral power to the maximum skin spectral power is between 0.9 and 1.2, and the P-wave polarity is unipolar with reversed polarity.

17. The computer-based method according to claim 1, wherein the P-wave is a P-segment.

18. A graphical user interface for a catheter positioning and navigation system, implemented as a computer-based method, comprising:

a first electrocardiogram (ECG) waveform area to display at least one real-time ECG waveform;

a second ECG waveform area to display at least one stored ECG waveform;

a catheter tip location area to display the location of the catheter tip within the vasculature;

a catheter tip location identification area to display quantitative characteristics of the ECG waveforms associated with different locations of the catheter tip location in the vasculature;

a control area including a plurality of control elements to enable a user to access a plurality of related functions either directly or remotely; and

means for automatically optimizing the display based on a plurality of parameters.

19. An adaptor for endovascular electrocardiography, comprising:

a member having two ends and an inner lumen such that when one of the ends is connected to a catheter and the other end is connected to a syringe, fluid from the syringe is flushed into the catheter through the inner lumen; and

a metal insert, disposed along the inner lumen of the member, which connects through a sealed electrical connection to the outer side of the member.

20. A method for guidance and navigation of an endovascular access device, comprising:

placing one, two or three skin electrodes on a patient;

introducing an endovascular access device, coupled to an electrode thorough a conductive path passing through the endovascular access device, into the patient; and

determining a location of the tip of the endovascular access device based on electrical signals received from the skin electrodes and the endovascular electrode,

wherein, if one skin electrode is placed on the patient, the skin electrode is placed on the lower left abdomen,

wherein, if two skin electrodes are placed on the patient, the first skin electrode is placed on the lower left abdomen, and the second skin electrode is placed on the left shoulder, and

wherein, if three skin electrodes are placed on the patient, the first skin electrode is placed on the lower left abdomen, the second skin electrode is placed on the left shoulder and the third skin electrode is placed on the lower right abdomen.