Patent ID: 7217253

Claim:
A method for infusing a fluid medicament into a patient which comprises the steps of: engaging a reservoir in fluid communication with a body member, wherein the reservoir is filled with the fluid medicament and the body member is formed with a fluid pathway having a first opening and a second opening, and further wherein the reservoir is engaged with the first opening of the fluid pathway; establishing fluid communication between an impulse chamber having a nozzle and the second opening of the pathway; transferring a partial dose of the fluid medicament from the reservoir, through the pathway and into the impulse chamber to leave a remainder dose in the reservoir; using a first plunger in said impulse chamber to inject the partial dose of fluid medicament from said impulse chamber through the nozzle and into the patient at a first fluid pressure; and advancing a second plunger into the reservoir to infuse the remainder dose from the reservoir through the nozzle and into the patient at a second fluid pressure, wherein said first fluid pressure is greater than said second fluid pressure.