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EP-4129384-B1 - CANNULA CAPTURE MECHANISM

EP4129384B1EP 4129384 B1EP4129384 B1EP 4129384B1EP-4129384-B1

Inventors

  • BURKHOLZ, JONATHAN KARL
  • SHEVGOOR, SIDDARTH K.

Dates

Publication Date
20260506
Application Date
20170317

Claims (10)

  1. A catheter device, comprising: a cannula capture mechanism (12) comprising: an outer housing (20); an inner housing (18), wherein at least a portion of the inner housing is disposed within a distal end (38) of the outer housing (20), characterized in that the distal end (38) of the outer housing (20) comprising a fixed inner diameter that is substantially radially rigid, the inner housing (18) further comprising an interlock component (46) coupled to a distal portion (40) of the inner housing (18); and a cannula (14) configured to extend into the inner housing, wherein when the cannula is exposed from a distal end (36) of the inner housing (18), the distal portion (40) of the inner housing has a first diameter (42), and the interlock component has a first outer diameter, and wherein when the cannula is retracted proximally within the inner housing, the distal portion (40) of the inner housing has a second diameter (44) that is less than the first diameter (42), and the interlock component has a second outer diameter that is less than the first outer diameter, wherein the second diameter is also less than the inner diameter of the distal end (38) such that when the distal portion (40) has the second diameter (44), the distal end (38) of the outer housing (20) is configured to slide distally over the distal portion (40) of the inner housing to seal the distal end (36) of the inner housing, wherein the first and second outer diameters of the interlock component (46) are greater than the fixed inner diameter of the distal end (38) of the outer housing (20).
  2. The catheter device of claim 1, wherein when the cannula is retracted proximally within the inner housing, the outer housing is configured to decompress.
  3. The catheter device of claim 1, wherein the inner housing comprises a plurality of arms (32), wherein when the cannula is exposed from the distal end of the inner housing, the cannula is configured to bias the plurality of arms apart.
  4. The catheter device of claim 3, wherein the distal portion of the inner housing comprises at least a portion of the plurality of arms.
  5. The catheter device of claim 3, wherein the plurality of arms extends distally from a proximal end of the inner housing.
  6. The catheter device of claim 1, wherein the cannula comprises a cannula feature (16), wherein when the cannula is retracted proximally within the inner housing, the cannula feature is configured to contact a proximal end (50) of the inner housing to prevent the cannula from exiting the proximal end of the inner housing.
  7. The catheter device of claim 1, wherein the outer housing comprises a baffled portion constructed of an elastomeric material.
  8. The catheter device of claim 1, further comprising a catheter adapter (22), wherein an inner surface of the catheter adapter is configured to secure the interlock component of the inner housing within the catheter adapter when the cannula is exposed from the distal end of the inner housing, and to separate the interlock component from the inner housing to release the inner housing from the catheter adapter when the cannula is retracted proximally within the inner housing.
  9. The catheter device of claim 8, further comprising a septum activator (68), wherein the septum activator is disposed within an inner lumen (47) of the catheter adapter, wherein an inner surface of the septum activator is configured to separate from the interlock component of the inner housing when the cannula is retracted proximally within the inner housing.
  10. The catheter device of claim 1, wherein the outer housing is configured to move between a compressed state and an decompressed state, and wherein when the cannula is exposed from a distal end of the inner housing, the interlock component interacts with an interlock surface formed in an inner surface of the catheter device, wherein when the cannula is retracted proximally within the inner housing, the interlock component of the inner housing contracts radially inward to separate from the interlock surface, and the outer housing decompresses distally to extend the distal end (38) over the distal portion (40) of the inner housing to prevent the cannula from exiting the distal end (36) of the inner housing (18).

Description

BACKGROUND OF THE INVENTION This disclosure relates generally to vascular access devices. More specifically, this disclosure discusses a cannula capture mechanism that is configured to capture a cannula tip in a manner that locks the cannula in a shielded position. The cannula capture mechanism can be used with catheter assemblies. Generally, vascular access devices are used for communicating fluid with the vascular system of patients. For example, catheters are used for infusing fluid (e.g., saline solution, medicaments, and/or total parenteral nutrition) into a patient, withdrawing fluids (e.g., blood) from a patient, and/or monitoring various parameters of the patient's vascular system. Intravenous (IV) catheter assemblies are among the various types of vascular access devices. Over-the-needle peripheral IV catheters are a common IV catheter configuration. As its name implies, an over-the-needle catheter is mounted over an introducer needle having a sharp distal tip. The introducer needle is generally a hypodermic needle coupled to a needle assembly to help guide the needle and to facilitate its cooperation with the catheter. At least the inner surface of the distal portion of the catheter tightly engages the outer surface of the needle to prevent peelback of the catheter and, thereby, facilitate insertion of the catheter into the blood vessel. The catheter and the introducer needle are often assembled so that the distal tip of the introducer needle extends beyond the distal tip of the catheter. Moreover, the catheter and needle are often assembled so that, during insertion, the bevel of the needle faces up, away from the patient's skin. The catheter and introducer needle are generally inserted at a shallow angle through the patient's skin into a blood vessel. In order to verify proper placement of the needle and/or catheter in the blood vessel, the operator generally confirms that there is "flashback" of blood into a flashback chamber associated with the needle assembly. Flashback generally entails the appearance of a small amount of blood, which is visible within the needle assembly or between the needle and the catheter. Once proper placement of the distal tip of the catheter into the blood vessel is confirmed, the operator may apply pressure to the blood vessel by pressing down on the patient's skin over the blood vessel, distal to the introducer needle and the catheter. This finger pressure momentarily occludes the vessel, minimizing further blood flow through the introducer needle and the catheter. The operator may then withdraw the introducer needle from the catheter. The needle may be withdrawn into a needle tip cover or needle cover that extends over the needle's tip and prevents accidental needle sticks. In general, a needle tip cover includes a casing, sleeve, or other similar device that is designed to trap/capture the needle tip when the introducer needle is withdrawn from the catheter and the patient. After the needle is withdrawn, the catheter is left in place to provide intravenous access to the patient. The separation of the introducer needle assembly from the catheter portions of the catheter assembly presents numerous potential hazards to the operators and others in the area. As indicated above, there is a risk of accidental needle sticks if the needle tip is not secured properly in a needle tip shield. Additionally, because the needle has been in contact with blood in the patient's vasculature, blood is often present on the needle's exterior as well as inside the lumen of the needle. As the needle is withdrawn from the catheter, there is a risk that this blood will drip from the needle tip or come into contact with other surfaces to expose people and equipment to blood. Additionally, it has been observed that withdrawing a needle from a catheter assembly often imparts energy to the parts of the needle assembly. For instance, during needle withdrawal, bending forces can be applied (either unintentionally or intentionally) to the needle. Such energy has been observed to cause blood to splatter or spray from the needle when the needle vibrates and shakes as it becomes free from the catheter assembly and releases the stored energy. The present disclosure discusses a cannula capture mechanism that allows a needle to be retracted from an unshielded position to a shielded position in which the cannula feature is trapped. Accordingly, the described capture mechanism is configured to lock the needle in the shielded position to significantly limit or prevent accidental sticks and blood exposure after the needle is withdrawn from a catheter assembly. US 2013/023835 A1 discloses a needle guard assembly. US 2014/039399 A1 discloses a bi-directional cannula feature capture mechanism. WO 2015/082559 A1 discloses a safety needle assembly with a needle guard having a retention mechanism. US 5,486,164 A discloses a passive protector for hypodermic needles. BRIEF SUMMARY OF THE INVENTION The invention i