Tissue penetration device
View Patent ↗A method of lancing the tissue of a patient provides a tissue penetration element with a tip configured to penetrate tissue and a shaft portion. The tissue penetration element is disposed in proximity to the tissue of the patient. The tissue penetration element is driven distally towards the tissue of the patient. Contact is made between the tip and the tissue of the patient. The tip is advanced into the tissue during a penetration stroke to a position of maximum inward displacement. The tissue penetration element is displaced proximally over a withdrawal stroke at an average velocity that is substantially lower than an average velocity of the tissue penetration element during the penetration stroke. The tip is removed from the tissue.
1. A method of lancing the tissue of a patient comprising:
(a) providing a tissue penetration element having a tip configured to penetrate tissue and a shaft portion and a controllable electronic driver that can achieve a desired velocity versus position profile;
(b) disposing the tissue penetration element in proximity to the tissue of the patient;
(c) initiating a tissue penetrating element launch phase when the tissue penetrating element moves toward the skin and a tissue contact phase when a distal end of the tissue penetrating element makes initial contact with a skin surface;
(d) initiating a tissue deformation phase when the skin bends depending on its elastic properties;
(e) initiating a tissue lancing phase when the tissue penetrating element hits an inflection point on the skin and begins to cut the skin and the tissue penetrating element continues cutting the skin;
(f) displacing the tissue penetration element during a withdrawal stroke with an average velocity that is lower than an average velocity of the tissue penetration element during the penetration stroke with the tip remaining stationary at the position of maximum inward displacement of the patient for a predetermined time between the penetration stroke and the withdrawal stroke; and
(g) removing the tip from the tissue.
2. The method of claim 1 further comprising allowing the tissue penetration element to settle upon reaching the point of maximum inward penetration for at least about 1 millisecond, wherein no driving force is imposed on the tissue penetration element while settling.
3. The method of claim 1 further comprising allowing the tissue penetration element to settle upon reaching the point of maximum inward penetration for about 50 to about 2000 milliseconds, wherein no driving force is imposed on the tissue penetration element while settling.
4. The method of claim 1 wherein the average velocity of the tissue penetration element during the penetration stroke from the point of contact with the tissue until the position of maximum inward displacement is about 2 to about 8 meters per second.
5. The method of claim 1 wherein the average velocity of the tissue penetration element during the withdrawal stroke during which the tissue penetration element is moving proximally relative to tissue in contact with the tissue penetration element is about 0.001 to about 0.01 meters per second.
6. The method of claim 1 wherein the average velocity of the tissue penetration element during the penetration stroke from the point of contact with the tissue until the position of maximum inward displacement is about 2 to about 4 meters per second and wherein the average velocity of the tissue penetration element during the withdrawal stroke during which the tissue penetration element is moving proximally relative to tissue in contact with the tissue penetration element is about 0.001 to about 0.01 meters per second.
7. The method of claim 1 wherein the tissue comprises the skin of a human patient and the tip penetrates the skin to at the position of maximum inward displacement to a depth of about 0.5 to about 3.0 mm from an outer surface of the skin.
8. The method of claim 1 wherein the average velocity of the tissue penetration element during the penetration stroke is about 100 to about 1000 times greater than the average velocity of the tissue penetration member during the withdrawal stroke.
9. A method of lancing the tissue of a patient comprising:
(a) providing a tissue penetration element having a tip configured to penetrate tissue and a shaft portion and a controllable electronic driver that can achieve a desired velocity versus position profile;
(b) disposing the tissue penetration element in proximity to the tissue of the patient;
(c) initiating a tissue penetrating element launch phase when the tissue penetrating element moves toward the skin and a tissue contact phase when a distal end of the tissue penetrating element makes initial contact with a skin surface;
(d) initiating a tissue deformation phase when the skin bends depending on its elastic properties;
(e) initiating a tissue lancing phase when the tissue penetrating element hits an inflection point on the skin and begins to cut the skin and the tissue penetrating element continues cutting the skin;
(f) allowing the tissue penetration element to settle upon reaching the point of maximum inward penetration for about 1-200 milliseconds, wherein no driving force is imposed on the tissue penetration element while settling;
(g) displacing the tissue penetration element during a withdrawal stroke at an average velocity that is lower than an average velocity of the tissue penetration element during the penetration stroke with the tip remaining stationary at the position of maximum inward displacement in a tissue site of the patient for a time between the penetration stroke and the withdrawal stroke; and
(h) removing the tip from the tissue,