Methods and apparatus for suctioning and pumping body fluid from an incision

• US 20020111565A1
• Filed: 04/08/2002
• Published: 08/15/2002
• Est. Priority Date: 04/28/1998
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Inventors: Roe, Jeffrey N., Douglas, Joel S.
• Granted Patent: US 6,878,120 B2
• Time in Patent Office: Days
• US Class Current: 600/578
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150068 by tissue compression, e.g. with specially designed surface of device contacting the skin area to be pierced
• CPC Class Codes: A61B 5/150099 by negative pressure, other than vacuum extraction into a syringe by pulling on the piston rod or into pre-evacuated tubes
• CPC Class Codes: A61B 5/150229 Pumps for assisting the blood sampling
• CPC Class Codes: A61B 5/150412 Pointed piercing elements, e.g. needles, lancets for piercing the skin blade-like piercing elements A61B5/150442
• CPC Class Codes: A61B 5/15109 Fully automatically triggered, i.e. the triggering does not require a deliberate action by the user, e.g. by contact with the patient's skin
• CPC Class Codes: A61B 5/15113 Manually triggered, i.e. the triggering requires a deliberate action by the user such as pressing a drive button
• CPC Class Codes: A61B 5/15117 comprising biased elements, resilient elements or a spring, e.g. a helical spring, leaf spring, or elastic strap
• CPC Class Codes: A61B 5/15186 Devices loaded with a single lancet, i.e. a single lancet with or without a casing is loaded into a reusable drive device and then discarded after use; drive devices reloadable for multiple use
• CPC Class Codes: A61B 5/15194 fully automatically retracted, i.e. the retraction does not require a deliberate action by the user, e.g. by terminating the contact with the patient's skin

Abstract

A sampling device for sampling body fluid includes a casing which is pressed against a skin surface to produce a seal therewith. A cocking mechanism is pulled rearwardly to place a lancing device in a cocked state. By releasing a trigger, the lancing device is driven forward to produce an incision in the skin, and then is retracted out of the incision. A plunger mounted on the cocking mechanism is then retracted to generate a negative pressure at the front end of the casing to draw body fluid from the incision.

Claims

1. A sampling device for sampling body fluid, comprising:

a casing defining a longitudinal axis;

a skin-lancing mechanism for extending a lance through a longitudinal front end of the casing and against a skin surface to form an incision therein, and then retracting the lance back into the housing;

a trigger for releasably holding the skin-lancing mechanism from in a cocked state;

an actuator for displacing the trigger to a release position for releasing the skin-lancing mechanism; and

a plunger arranged separated from the actuator and being longitudinally rearwardly movable relative to both the skin-lancing mechanism and the actuator for generating a negative pressure at the front end of the casing to draw body fluid from the incision.

2. The sampling device according to claim 1 further including a cocking mechanism connected to the skin-lancing mechanism and being longitudinally movable relative to the housing for positioning the skin-lancing mechanism in a cocked state, the plunger being longitudinally rearwardly movable relative to the cocking mechanism.

3. The sampling device according to claim 1 wherein the plunger is spring biased in a direction away from the front end of the casing.

4. The sampling device according to claim 1 wherein the casing includes a housing and a hollow ring member mounted at a front end of the housing for longitudinal movement relative thereto, the ring member including an annular front surface for engaging a skin surface and establishing a seal therewith, the ring member including a rear end arranged to trip the trigger in response to rearward movement of the ring member relative to the housing.

5. The sampling device according to claim 4 wherein the ring member constitutes a radially outer ring, the casing further including a radially inner ring situated coaxially with the outer ring and having a front face arranged to engage a skin surface in response to rearward movement of the outer ring relative to the housing, for increasing blood expression from the wound and breaking the sealing engagement between the skin surface and the front end face of the outer ring.

6. A method of obtaining a sample of body fluid from a body, the method employing a device comprising a casing, a skin-lancing mechanism and cocking mechanism disposed in the casing, a trigger mounted on the casing for holding the skin-lancing mechanism in a cocked state, a plunger mounted on the casing for longitudinal movement relative thereto, a hollow outer ring mounted at a front longitudinal end of the casing for longitudinal movement relative thereto, the outer ring including an annular front surface for engaging a skin surface and establishing a seal therewith, and an inner ring situated coaxially within the outer ring and having a front face;

the method comprising the steps of;

A) orienting the skin-lancing mechanism in a cocked state;

B) positioning the front end of the outer ring against a skin surface to form a seal therewith, with the plunger held in a forward position;

C) displacing the casing forwardly to displace the outer ring rearwardly relative thereto, whereby a rear end of the outer ring releases the skin-lancing mechanism from the cocked state, and a spring extends a lance of the released skin-lancing mechanism forwardly and against the skin surface to form an incision therein, and then retracts the lancing mechanism;

D) longitudinally rearwardly retracting the plunger relative to both the skin-lancing mechanism and the outer ring for generating a negative pressure at the front end of the outer ring to draw body fluid from the incision;

E) displacing the casing forwardly to cause the inner ring to engage the skin surface and express additional body fluid therefrom while breaking the seal between the outer ring and the skin surface;

F) removing the device from the skin surface;

G) moving the plunger forwardly; and

H) repeating steps A, B, D, and E at least once to increase the quantity of expressed body fluid.