Apparatus and methods to create posterior compression at the breast during expression of breast milk
Improved devices and methods for the expression of milk from a breast are disclosed herein. A device for expressing breast milk may comprise a breast interface including a flange configured to engage a breast and fluidly seal thereagainst, and an actuatable assembly operably coupled to the breast interface and configured to apply vacuum pressure at the breast interface. The breast interface may be configured to apply anterior compression to an anterior portion of the breast when the actuatable assembly is actuated. The flange may be configured to apply posterior compression to a posterior portion of the breast when the actuatable assembly is actuated. The posterior compression can help improve the efficiency of milk expression by reducing the retrograde flow of milk.
1. A device for expression of breast milk from a breast, the device comprising:
a breast interface comprising a flange configured to engage the breast and fluidly seal thereagainst; and
an actuatable assembly operably coupled to the breast interface and configured to generate negative pressure at the breast interface when actuated,
wherein the flange includes a movable member comprising a lever, the lever having a first arm and a second arm, the lever configured to rotate about a pivot point to apply a posterior compression to the breast, the first arm configured to engage an anterior portion of the breast and the second arm configured to engaged a posterior portion of the breast when the breast is fluidly sealed against the flange,
wherein the first arm of the lever is configured to apply an anterior compression to the breast in response to generation of negative pressure at the breast interface, and
wherein the lever is configured to move in response to the anterior compression of the breast against the first arm of the lever, to subsequently apply the posterior compression to the breast with the second arm of the lever.
2. The device as in claim 1 , wherein the first arm of the lever is configured to move away from the breast and the second arm of the lever is configured to move towards the breast in response to generation of the negative pressure at the breast interface.
3. The device as in claim 1 , wherein the movable member is configured to apply the anterior compression and the posterior compression in a temporally coupled manner, such that, when the negative pressure is applied at the breast interface, the anterior compression is applied first and the posterior compression is applied second.
4. The device as in claim 1 , wherein the lever is coupled to an interior surface of the flange via the pivot point.
5. The device as in claim 4 , wherein the first and second arms joined about the pivot point, wherein the first arm is configured to apply the anterior compression and the second arm is configured to apply the posterior compression to the breast.
6. The device as in claim 5 , wherein the lever is configured such that greater moment is applied to the first arm than to the second arm when the breast compresses against the lever.
7. The device as in claim 5 , wherein a longitudinal axis of the first arm and a longitudinal axis of the second arm are non-collinear.
8. The device as in claim 5 , wherein a length of the first arm is different from a length of the second arm.
9. The device as in claim 1 , wherein the lever comprises a substantially rigid member of the flange coupled to a flexible member of the flange, and wherein the substantially rigid member of the flange is configured to rotate about the pivot point, disposed near an anterior portion of the substantially rigid member, to apply the posterior compression.
10. The device as in claim 9 , wherein the flexible member comprises an anterior portion configured to bend in response to compression of the breast against the lever, and wherein the substantially rigid member is configured to rotate about the pivot point in response to the bending of the anterior portion of the flexible member.
11. The device as in claim 1 , further comprising a flexible cover disposed over the lever to enclose the lever, the flexible cover configured to fluidly seal against the breast and to allow rotation of the lever within the flexible cover, thereby reducing pinching of the breast by the lever during rotation.
12. The device as in claim 1 , wherein the flange comprises a plurality of movable members distributed annularly about the flange.
13. The device as in claim 1 , wherein the movable member comprises a single, continuous movable member extending annularly about the flange.
14. The device as in claim 1 , wherein the breast interface further comprises a housing and a membrane disposed within and coupled to the housing, wherein the membrane comprises an expandable portion configured to move toward the housing and away from the breast in response to actuation of the actuatable assembly to apply negative pressure at the breast interface.
15. The device as in claim 14 , wherein the membrane comprises a flexible cover portion disposed over the movable member to enclose the movable member, the flexible cover portion configured to fluidly seal against the breast and to allow movement of the movable member within the flexible cover portion.
16. The device as in claim 14 , wherein the membrane is shaped to form the flange, wherein the movable member comprises a substantially rigid portion of the flange, and wherein the substantially rigid portion of the flange comprises a thickness that is greater than a thickness of the membrane at the expandable portion.