Two-stage fluid medicament jet injector
First Claim
1. An apparatus for injecting a fluid medicament through a skin area into a patient, which comprises:
- a chamber for containing the fluid medicament, said chamber having an aperture;
a drive mechanism for selectively exerting forces on the fluid in said chamber to sequentially expel the fluid through said aperture in two stages, said stages being an impulse stage characterized by a first force on the fluid wherein fluid punctures the skin area of the patient to create a hole through the skin, and a perfusion stage characterized by a second force on the fluid wherein fluid is injected into the patient through the hole, said second force being less than said first force;
an injection tube formed with a lumen and having a first end and a second end, said first end of said injection tube being attached to said chamber to extend said injection tube therefrom with said lumen in fluid communication with said chamber through said aperture;
a skirt attached to said chamber and extending therefrom to surround said injection tube and establish a suction compartment therebetween, said skirt being distanced from said second end of said injection tube to establish an opening into said suction compartment; and
a vacuum source in fluid communication with said suction compartment for creating a subcutaneous pocket in said suction compartment for infusion of said fluid medicament.
3 Assignments
0 Petitions
Accused Products
Abstract
A jet injector, and a method, for injecting fluid medicament into a patient in a two-stage process. During the first stage fluid is expelled from the injector under relatively high pressure, to create a hole through the skin of the patient. During the second stage, fluid is infused through the hole into the patient at a much lower pressure, and for a much longer period of time. The jet injector includes a syringe unit, and a drive mechanism which is selectively connectable with the syringe unit. Specifically, the drive mechanism includes two springs which are positioned to urge against a push rod as they elongate. When the drive mechanism is engaged with the syringe unit, the push rod is positioned longitudinally co-linear with a plunger in the chamber. When the springs are released, they push the push rod which, in turn, pushes the plunger, causing the fluid to be expelled through an injection tube connected to the chamber. The syringe unit also includes a suction compartment for pulling the skin against a syringe tip at the end of the injection tube. To prepare the injector, the chamber of the syringe unit is filled with a fluid medicament, the drive mechanism is cocked, and the syringe unit is engaged with the drive mechanism. A vacuum source is then connected in fluid communication with the suction compartment. The syringe tip and the opening to the suction compartment are then pressed against the skin, and the injector is activated.
125 Citations
16 Claims
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1. An apparatus for injecting a fluid medicament through a skin area into a patient, which comprises:
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a chamber for containing the fluid medicament, said chamber having an aperture; a drive mechanism for selectively exerting forces on the fluid in said chamber to sequentially expel the fluid through said aperture in two stages, said stages being an impulse stage characterized by a first force on the fluid wherein fluid punctures the skin area of the patient to create a hole through the skin, and a perfusion stage characterized by a second force on the fluid wherein fluid is injected into the patient through the hole, said second force being less than said first force; an injection tube formed with a lumen and having a first end and a second end, said first end of said injection tube being attached to said chamber to extend said injection tube therefrom with said lumen in fluid communication with said chamber through said aperture; a skirt attached to said chamber and extending therefrom to surround said injection tube and establish a suction compartment therebetween, said skirt being distanced from said second end of said injection tube to establish an opening into said suction compartment; and
a vacuum source in fluid communication with said suction compartment for creating a subcutaneous pocket in said suction compartment for infusion of said fluid medicament. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. An apparatus for injecting a fluid medicament through a skin area into a patient, which comprises:
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a chamber for containing the fluid, said chamber having an aperture; a plunger mounted on said chamber for movement into said chamber to expel the fluid through said aperture; actuator means for exerting forces on said plunger to expel the fluid from said chamber through said aperture and to sequentially puncture the skin area of the patient to create a hole therethrough and to cause the fluid to infuse into the patient through the hole; a suction compartment attached to said chamber, said suction compartment having an opening surrounding said aperture, said suction compartment having a suction port; and a vacuum source attachable in fluid communication with said suction port for establishing a partial vacuum in said suction compartment, to pull the skin area against said aperture and into said suction compartment to create a subcutaneous pocket for infusion of said fluid medicament. - View Dependent Claims (13, 14)
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15. A method for injecting a fluid medicament through a skin area into a patient, which comprises the steps of:
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providing a syringe unit, said syringe unit being formed with a chamber having an aperture, said chamber for containing the fluid and wherein said syringe unit further comprises a suction compartment having an opening surrounding said aperture, and wherein said suction compartment is formed with a suction port; providing a drive mechanism for selectively exerting forces on the fluid in said chamber to sequentially expel the fluid through said aperture in two stages, said stages being an impulse stage characterized by a first force wherein the fluid punctures the skin area of the patient to create a hole through the skin area, and a perfusion stage characterized by a second force wherein the fluid is injected into the patient through said hole, said second force being less than said first force; cocking said drive mechanism; placing the fluid in said chamber; engaging said syringe unit with said drive mechanism; positioning said aperture against the skin area of the patient; connecting a vacuum source in fluid communication with said port in said suction compartment, for creating a partial vacuum in said suction compartment when said opening of said suction compartment is placed against the skin area of the patient to pull the skin area against said aperture and to create a subcutaneous pocket for infusion of said fluid; and activating said drive mechanism to cause the fluid to be expelled through said aperture in said two stages. - View Dependent Claims (16)
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Specification