Needle protective device for subcutaneous sensors

1. A method of covering an introducer needle comprising:

providing a sensor hub, a sensor, and an introducer, the introducer being configured to insert the sensor into a patient, the introducer comprising:

a housing detachably connectable to the sensor hub, wherein the sensor hub contains the sensor prior to connection to the housing, the housing including a needle cover, wherein the needle cover is an internal compartment of the housing;

a needle that is moveable with respect to the needle cover and is extendable out of, and retractable into, the housing;

a needle holder connected to the needle and contained within the housing; and

a spring having a top end in contact with the needle holder and a bottom end in contact with the housing,

wherein said needle holder and spring are configured such that, when the housing is connected to the sensor hub, said spring is in a compressed position and the needle extends out of the housing to insert the sensor into the patient, and such that disconnection of the housing from the sensor hub causes said spring to expand, thereby retracting the needle into the housing to be covered by said needle cover inside the housing, and the sensor remaining inserted in the patient;

wherein the housing includes a mating component to mate with the sensor hub and hold said spring in said compressed position when the housing is connected to the sensor hub; and

wherein the mating component includes a lock that locks the needle holder into a needle extended position when the housing is connected to the sensor hub, and when the mating component is not mated with the sensor hub the housing is completely detached from the sensor hub;

connecting the housing to the sensor hub so as to insert the sensor into the patient; and

disconnecting the housing from the sensor hub, whereby the needle cover covers the needle when the housing is detached from the sensor hub.

2. The method of claim 1 , wherein the needle holder is slidably coupled to the housing.

3. The method of claim 1 , wherein the housing and the mating component are configured such that disconnection of the housing from the sensor hub causes the mating component to release the needle holder such that the needle holder may move the needle to be covered.

4. The method of claim 1 , wherein the mating component is held in a locking position by friction when the housing is connected to the sensor hub.

5. The method of claim 1 , wherein the mating component includes a catch that catches on the sensor hub when the housing is connected to the sensor hub, whereby the mating component is held in a locking position by the catch.

6. The method of claim 1 , wherein the needle is permanently covered by the needle cover after the housing is disconnected from the sensor hub.

7. The method of claim 1 , wherein the needle holder has a top portion that defines an indentation therein, said indentation extending radially inwards from a periphery of said top portion, and wherein, when the housing is connected to the sensor hub, said lock extends into, and engages with, said indentation on the needle holder's top portion, thereby locking the needle holder in the needle extended position.

8. The method of claim 1 , wherein the needle holder has a top portion that defines two indentations therein, wherein the housing includes a second mating component, wherein said second mating component includes a second lock, and wherein, when the housing is connected to the sensor hub, each said lock extends into, and engages with, a respective one of said indentations, thereby locking the needle holder in the needle extended position.

9. The method of claim 8 , wherein each said mating component includes an arm, and wherein the arms are moveable towards, and away from, each other.

10. The method of claim 9 , wherein, when the arms are moved towards one another, each said lock extends into, and engages with, a respective one of said indentations on the needle holder's top portion, and when the arms are moved away from one another, each said lock disengages from each said respective indentation.