Dampening devices and methods for needle retracting safety vascular access devices

• US 6,090,078 A
• Filed: 09/30/1997
• Issued: 07/18/2000
• Est. Priority Date: 09/30/1997
• Status: Expired due to Term

• Current Assignee: Becton, Dickinson & Co
• Original Assignee: Becton, Dickinson & Co
• Inventors: Erskine, Timothy J.
• Primary Examiner(s): Coggins, Wynn Wood
• Assistant Examiner(s): Thanh, LoAn H.
• Application Number:
  US08/941,450
• Time in Patent Office: 1,022 Days
• Field of Search: 604/110, 604/122, 604/126, 604/162, 604/164-166, 604/168, 604/171, 604/221-222, 604/226, 604/230-231, 604/240, 604/243, 604/263, 604/195, 604/198, 128/919
• US Class Current: 604/198
• CPC Class Codes: A61M 2005/3143 Damping means for syringe components executing relative movements, e.g. retarders or attenuators slowing down or timing syringe mechanisms
• CPC Class Codes: A61M 25/0631 having means for fully covering the needle after its withdrawal, e.g. needle being withdrawn inside the handle or a cover being advanced over the needle
• CPC Class Codes: A61M 25/0693 Flashback chambers
• CPC Class Codes: A61M 5/3232 Semi-automatic needle retraction, i.e. in which triggering of the needle retraction requires a deliberate action by the user, e.g. manual release of spring-biased retraction means
• CPC Class Codes: Y10S 128/919 Syringe, means to protect user

Abstract

Devices and methods for slowing down or dampening the retraction velocity of an introducer needle used in connection with needle retracting safety vascular access devices. The devices and methods prevent splattering or dripping of blood caused by an introducer needle that retracts too quickly. The dampening devices can be easily modified to regulate the amount of dampening desired and can be retrofitted to existing vascular access devices designs.

Claims

1. A vascular access device comprising:

a. a hollow housing having a distal end, a proximal end, and a cavity with a length;

b. an introducer needle having a proximal end and a distal end;

c. a hub in communication with the needle sized to travel the length of the housing cavity;

d. a resilient member engaged with the hub, which applies a force and urges the needle in a distal direction;

e. a locking member for releasably locking the needle in an extended position against the force of the resilient member;

f. a dampening device located in the distal end of the cavity which generates air pressure during distal movement, the dampening device comprising an air vent for expelling pressurized air from the cavity and a piston disposed within the cavity, the piston including a circumferential groove and a viscous material disposed within the circumferential groove and in contact with the housing,

wherein when the locking member is released, the force on the needle causes the needle to retract distally at a velocity, distal movement of the dampening device expels air from the vent and the velocity of the needle is dampened by distal movement of the dampening device and distal movement of the piston causes friction of the viscous material against the housing to dampen velocity of the needle.

2. The vascular access device of claim 1, wherein the piston further comprises at least one o-ring positioned on said piston to prevent the viscous material from leaking during needle retraction.

3. The vascular access device of claim 2, wherein the resilient member device is a spring.