Patent Description:
The present disclosure generally relates to a medical apparatus for locating and accessing an intraosseous space of a patient. More specifically, the present disclosure relates to an intraosseous access device and locator assembly for placement of a conduit into the intraosseous space within a bone of a patient.

Many life-threatening emergencies, including shock, trauma, cardiac arrest, drug overdoses, diabetic ketoacidosis, arrhythmias, burns, and status epilepticus, just to name a few, often unnecessarily result in death because intravenous (IV) access cannot be achieved in a timely manner. An essential element for treating many life threatening emergencies is the rapid establishment of an IV line in order to administer drugs and fluids directly into a patient's vascular system. Whether in an ambulance by paramedics, in an emergency room by emergency specialists or on a battlefield by an Army medic, the goal is the same--quickly start an IV in order to administer lifesaving drugs and fluids. To a large degree, ability to successfully treat most critical emergencies is dependent on the skill and luck of an operator in accomplishing vascular access. While relatively easy to start an IV on some patients, doctors, nurses and paramedics may nevertheless experience difficulty establishing IV access in some patients. The success rate on the battlefield may be much lower, in which wounded soldiers are often probed repeatedly with sharp needles in an attempt to quickly establish IV access.

In the case of patients with chronic disease or the elderly, availability of easily accessible veins may be depleted. Other patients may have no available IV sites due to anatomical scarcity of peripheral veins, obesity, extreme dehydration or previous IV drug use. For such patients, finding a suitable site for administering lifesaving therapy often becomes a monumental and frustrating task. As a result, patients with life threatening emergencies may die when access to the vascular system with lifesaving IV therapy is delayed or simply not possible.

There are various circumstances under which it is desirable to introduce drugs or other liquids into the marrow of a subject's bone. For example, in cases where a subject has suffered from serious trauma or cardiac arrest it may not be practical to deliver liquids by way of intravenous (IV) infusions. Intraosseous infusion may also be useful for delivering fluids to newborns and small children in which suitable blood vessels are difficult to access. Intraosseous infusion may be used to deliver fluids into a subject's sternum, humerus, femur, tibia, or other bone. Intraosseous infusion has the advantage that, with appropriate technology, a pathway for intraosseous infusion can be established very rapidly. This can save lives in critical situations. Portals in bone may also be applied to withdraw or aspirate fluid from within the bone.

The intraosseous (IO) space provides a direct conduit to a patient's vascular system and provides an attractive alternate route to administer IV drugs and fluids. Drugs administered intraosseously enter a patient's blood circulation system rapidly, thus bone marrow may function as a large non-collapsible vein.

Proper placement of an intraosseous needle in the bone is critical. If a user attempts to insert the needle in the wrong place, the bone might be too thick and therefore difficult for the needle to penetrate. Alternatively, the bone might be too thin, in which case the needle could completely penetrate the anterior and posterior sides of the bone, thus missing the intraosseous region entirely. Also, placing the needle at an angle that is not substantially perpendicular to the surface of the bone may lead to the needle breaking, or other complications. Furthermore, certain powered drivers are unable to successfully penetrate bone when their respective power source is depleted. Additionally, the sharp penetrator tips of conventional driver assemblies can be dangerous if they are accidentally mishandled by a user prior to a planned insertion procedure. For instance, without adequate sharps protection, the user is susceptible to accidentally poking himself or another individual with the penetrator. <CIT> and <CIT> disclose devices of the prior art.

Therefore, a need exists for an intraosseous access device and locator assembly operable to locate a suitable insertion site and provide a quick and easy conduit to an intraosseous space within a bone of a patient.

Claim <NUM> defines the invention and dependent claims disclose embodiments. No surgical methods are claimed. The foregoing needs are met by implementations of an apparatus for accessing an intraosseous space within a bone of a patient according to the present disclosure. According to one aspect of the disclosure, the apparatus comprises a penetrator assembly having a sharp penetrating end configured to penetrate the bone and associated bone marrow; a manual driver coupled to the penetrator assembly, the manual driver including a handle operable to manually drive the penetrator assembly into the bone and associated bone marrow; and a protective shield having a distal end and a proximal end, the protective shield slidably coupled to the handle and defining a longitudinal hollow passageway extending between the distal end and the proximal end; where the protective shield is operable to move between an extended position in which the sharp penetrating end of the penetrator assembly is disposed within the longitudinal hollow passageway of the protective shield to provide sharps protection, and a retracted position in which the sharp penetrating end of the penetrator assembly is disposed outside the longitudinal hollow passageway of the protective shield to permit penetration of the penetrator assembly into the intraosseous space.

According to another aspect of the disclosure, the distal end of the protective shield defines an opening sized to receive the penetrator assembly.

According to another aspect of the disclosure, the distal end of the protective shield includes a blunt surface operable to contact a patient's skin without cutting the skin.

According to another aspect of the disclosure, the protective shield is removably coupled to the handle.

According to another aspect of the disclosure, the driver further comprises an internal recess configured to slidably receive the protective shield.

According to another aspect of the disclosure, the proximal end of the protective shield includes a resilient finger.

According to another aspect of the disclosure, at least two spaced-apart resilient fingers are disposed along a circumference of the proximal end of the protective shield.

According to another aspect of the disclosure, each resilient finger includes an outwardly protruding ridge configured to provide a friction fit within the internal recess of the driver to maintain the protective shield in a desired position.

According to another aspect of the disclosure, the internal recess has a shape corresponding to a shape of the protective shield.

According to another aspect of the disclosure, the protective shield is generally cylindrical, and the internal recess is correspondingly annular.

According to another aspect of the disclosure, the penetrator assembly further comprises an outer penetrator defining a longitudinal hollow bore, and an inner penetrator slidably receivable within the hollow bore of the outer penetrator.

According to another aspect of the disclosure, the inner penetrator comprises a rigid stylet, and the outer penetrator comprises a flexible cannula.

According to another aspect of the disclosure, an outer penetrator hub is coupled to the outer penetrator, the outer penetrator hub being removably attachable to the manual driver.

According to another aspect of the disclosure, the outer penetrator hub comprises a proximal end including an external threaded surface configured to releasably engage a corresponding internal threaded surface of the manual driver.

According to another aspect of the disclosure, the manual driver further comprises an inner penetrator hub coupled to the inner penetrator.

According to another aspect of the disclosure, a skirt extends from the handle.

According to another aspect of the disclosure, the skirt comprises a distal end having an outwardly extending flange.

According to another aspect of the disclosure, the handle has an ergonomic grip shape suitable for grasping during manual insertion of the penetrator assembly into the bone and associated bone marrow; and wherein the handle is configured to allow manual force to be applied and at the same time permit rotation of the handle.

According to another aspect of the disclosure, the apparatus further comprises a sternal locator including: a base having a first surface, a second surface, and a through-hole extending through the base; and a collar extending from the first surface of the base, the collar configured to secure the manual driver to restrict longitudinal separation of the manual driver from the locator, the collar surrounding the through-hole and defining a passageway configured to receive the protective shield for guiding insertion of the penetrator assembly into the intraosseous space without restricting movement of the protective shield between its extended and retracted positions during an insertion procedure.

According to another aspect of the disclosure, the collar further comprises a collar contact surface configured to contact a distal end of a skirt extending from the manual driver to impede further insertion of the penetrator assembly into the intraosseous space.

According to another aspect of the disclosure, the locator further comprises a bone probe extending from a second surface of the base.

According to another aspect of the disclosure, the locator is operable to be removed from the patient while an outer penetrator of the penetrator assembly remains inserted in the intraosseous space of the patient.

According to another aspect of the disclosure, a method of accessing an intraosseous space within a sternum of a patient comprises providing an intraosseous access device including a penetrator assembly having a sharp penetrating end, a manual driver coupled to the penetrator assembly, and a protective shield slidably coupled to the driver and defining a longitudinal hollow passageway; providing a sternal locator including a base having a first surface and a second surface, a through-hole extending through the first and second surfaces of the base, a collar extending from the first surface of the base and surrounding the through-hole, and a bone probe extending from the second surface of the base; positioning the through-hole of the sternal locator over the sternum; inserting the bone probe into the patient until the bone probe contacts the sternum; introducing the protective shield of the intraosseous access device into the through-hole in the base of the locator for guiding insertion of the penetrator assembly into the sternum; and manually inserting the penetrator assembly into the intraosseous space within the sternum.

According to another aspect of the disclosure, manually inserting the penetrator assembly comprises grasping an ergonomically-shaped handle of the driver and manually applying force toward the insertion site and at the same time manually turning the handle.

According to another aspect of the disclosure, a distal end of the protective shield contacts the patient's skin during insertion of the penetrator assembly into the intraosseous space.

According to another aspect of the disclosure, the protective shield is movable from an extended position to a retracted position during insertion of the penetrator assembly into the intraosseous space.

According to another aspect of the disclosure, the penetrator assembly comprises an inner penetrator and an outer penetrator, the inner penetrator slidably disposed within a longitudinal hollow bore of the outer penetrator.

According to another aspect of the disclosure, the inner penetrator is withdrawn from the outer penetrator while the outer penetrator remains inserted within the intraosseous space.

According to another aspect of the disclosure, the locator is withdrawn from the patient while the outer penetrator remains inserted within the intraosseous space.

According to another aspect of the disclosure, the protective shield is moved back to the extended position from the retracted position during withdrawal of the inner penetrator from the intraosseous space to provide sharps protection for the inner penetrator.

There has thus been outlined certain aspects of the disclosure in order that the detailed description thereof may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional implementations of the disclosure that will be described below and which form the subject matter of the claims appended hereto.

In this respect, before explaining at least one aspect of the intraosseous access device in detail, it is to be understood that the apparatus is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The intraosseous access device is capable of aspects in addition to those described, and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.

As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, and systems for carrying out the several purposes of the intraosseous access device.

In order that the disclosure may be readily understood, aspects of the intraosseous (IO) access device are illustrated by way of examples in the accompanying drawings, in which like parts are referred to with like reference numerals throughout.

The present disclosure provides an intraosseous access device and locator assembly for locating a suitable insertion site and penetrating the underlying bone, such as a human patient's sternum, and quickly and easily providing a conduit to an intraosseous space within the bone for associated medical procedures, including delivery of fluid and medication, aspiration, and biopsy of bone marrow, among others.

<FIG> depicts a schematic view of the ribcage <NUM> of a human. The sternum <NUM> is a flat, narrow bone between the ribs <NUM> comprising three segments: the manubrium, the body, and the xiphoid process. The sternum also comprises a sternal notch <NUM> (also called the "suprasternal notch" or the "jugular notch"), which is a U-shaped anatomical feature located above the sternum, below the throat, and between the clavicles. <FIG> shows a cross-sectional view of a portion of the sternum <NUM>. Skin <NUM> overlays a layer of subcutaneous tissue <NUM>, which in turn overlays bone <NUM>. Bone <NUM> includes an intraosseous space <NUM> bounded by anterior compact bone (i.e., anterior cortex) <NUM> and posterior compact bone (i.e., posterior cortex) <NUM>. Stated another way, the intraosseous space <NUM> is the region in the bone between the anterior cortex and the posterior cortex. Bone marrow includes blood, blood forming cells, and connective tissue found in the intraosseous space.

Anterior compact bone <NUM> and posterior compact bone <NUM> are each approximately <NUM> millimeters (mm) thick and intraosseous space <NUM> is approximately <NUM> thick in most adult patients. Thus, the total thickness of bone <NUM> is approximately <NUM>. The target zone within the intraosseous space <NUM> is the center, which is approximately <NUM> from the upper surface of anterior compact bone <NUM> in most adult patients.

The intraosseous space <NUM> may be accessed by an intraosseous (IO) access device, which may include, but is not limited to, a penetrator assembly comprising a hollow needle, hollow drill bit, bone penetrator, catheter, cannula, trocar, stylet, inner penetrator, outer penetrator, needle or needle set, or other device operable to provide access to an intraosseous space or interior portions of a bone. Such IO access devices may be formed, at least in part, from metal alloys such as <NUM> stainless steel and other biocompatible materials associated with needles and similar medical devices. A wide variety of IO access devices may be formed in accordance with one or more teachings of the present disclosure. For instance, trocars, spindles, and/or shafts may be disposed within a cannula during insertion at a selected insertion site. Inner penetrators may include such trocars, spindles, and shafts, among others. Further, inner penetrators may comprise various lengths including, but not limited to, <NUM> to <NUM> millimeters (e.g., between <NUM> and <NUM>, <NUM>, and/or the like). Outer penetrators may include catheters, cannulas, hollow needles, and hollow drill bits, among others. In some implementations, the penetrator assembly may include a flexible outer penetrator and a rigid inner penetrator as disclosed in international patent application no. PCT/IB2019/<NUM>.

<FIG> illustrates an implementation of an IO access device <NUM> of the present disclosure and its components, the IO access device configured for manual insertion into a subject's intraosseous space. The intraosseous access device <NUM> comprises a manual driver <NUM> that includes a handle or grip <NUM> connected to an inner penetrator hub <NUM>, which is attached to a rigid inner penetrator <NUM>. The inner penetrator <NUM> may, for example, take the form of any suitable stylet or trocar. The inner penetrator <NUM> includes a distal end having a tip <NUM> configured to penetrate bone and associated bone marrow. The inner penetrator <NUM> further includes a proximal end that may have a notch <NUM> configured to assist in coupling the inner penetrator hub <NUM> to the inner penetrator <NUM>, as shown in <FIG>. For instance, the inner penetrator hub <NUM> may be overmolded over the inner penetrator <NUM> such that the material from the inner penetrator hub may be molded to extend into the notch <NUM>. The inner penetrator hub <NUM> is surrounded by an annular skirt <NUM> connected to and extending from the handle <NUM>. A distal end <NUM> of the skirt <NUM> includes an annular flange <NUM> radially extending outwardly therefrom. In some implementations, the inner penetrator <NUM> extends from the handle or grip <NUM>, and furthermore extends from the distal end <NUM> of the skirt <NUM>.

The IO access device <NUM> also includes an outer penetrator hub <NUM> that is coupled to an outer penetrator <NUM>. The outer penetrator <NUM> may, for example, take the form of a hollow tube, such as cannula (e.g., a metal cannula), or a hollow drill bit, and which may be configured (e.g., to possess sufficient rigidity) such that the outer penetrator <NUM> will not buckle or otherwise be damaged as it is inserted through anterior compact bone together with the inner penetrator <NUM>. In other implementations, the outer penetrator <NUM> may be flexible so that it may be manipulated after insertion into the intraosseous space (i.e., by bending a portion of the outer penetrator to secure it, along with the outer penetrator hub <NUM>, against the patient's skin to provide a lower profile). The outer penetrator hub <NUM> includes a proximal end <NUM> and a distal end <NUM>. The outer penetrator <NUM> also includes a proximal end and a distal end <NUM>, the proximal end of the outer penetrator <NUM> coupled to the outer penetrator hub <NUM>. The outer penetrator distal end <NUM> includes a cutting surface operable to penetrate bone and associated marrow. The outer penetrator <NUM> extends from the distal end <NUM> of the outer penetrator hub <NUM>.

The inner penetrator hub <NUM> is configured to removably attach to the outer penetrator hub <NUM>. More particularly, the proximal end <NUM> of the outer penetrator hub <NUM> and the inner penetrator hub <NUM> may be configured as complimentary connectors (with, for example, the inner penetrator hub <NUM> including a female Luer connector and the proximal end <NUM> of the outer penetrator hub <NUM> being configured as a male Luer connector, although these configurations could be reversed in other implementations) to allow the manual driver <NUM> to be removably coupled to the outer penetrator <NUM>. For example, the outer penetrator hub <NUM> (and, more specifically, the proximal end <NUM> of the outer penetrator hub <NUM>) may include an external surface <NUM> that is threaded and that is proximate a passageway that is in fluid communication with the passageway of outer penetrator <NUM>. The inner penetrator hub <NUM> may include an internal surface <NUM> that is threaded to mate with the external threaded surface <NUM> at the proximal end <NUM> of the outer penetrator hub <NUM>. The internal threaded surface <NUM> is proximate to and surrounds a male projection that is tapered to match an inwardly-tapered recess in the proximal end <NUM> of the outer penetrator hub <NUM>.

The outer penetrator <NUM> comprises a longitudinal passageway configured to slidably receive a portion of the inner penetrator <NUM> when the inner penetrator hub <NUM> is attached to the outer penetrator hub <NUM>, thus forming a penetrator assembly. The handle or grip <NUM> of the manual driver <NUM> is configured to manually drive the penetrator assembly into an intraosseous space, such that the handle or grip has an ergonomic shape, such as a round or dome-shaped grip, suitable for grasping and manually applying force during manual insertion of the inner and outer penetrators into the bone and associated bone marrow. The handle or grip <NUM> is configured to allow manual force to be applied and at the same time permit rotation of the handle during insertion of the penetrator assembly into the IO space.

When the driver <NUM> and the outer penetrator <NUM> are coupled to each other, the inner penetrator <NUM> is disposed within the passageway of the outer penetrator <NUM>, and the inner penetrator tip <NUM> extends beyond the distal end <NUM> of the outer penetrator <NUM>. The inner penetrator tip <NUM> and the outer penetrator distal end <NUM> are each operable to penetrate bone and associated bone marrow. More particularly, the inner penetrator tip <NUM> and the outer penetrator distal end <NUM> are configured to cooperate with each other to form a penetrator assembly tip operable to penetrate bone and associated bone marrow when the inner penetrator hub <NUM> is attached to the outer penetrator hub <NUM>.

The IO access device <NUM> may further comprise a protective shield or cover <NUM>, as depicted in <FIG> and <FIG>. The cover <NUM> is configured to move between a first or extended position operable to provide sharps protection from the distal ends of the inner and outer penetrators, and a second or retracted position operable to guide insertion of the penetrator assembly into an IO space at an insertion site when using a locator, as will be discussed in further detail below. The cover <NUM> includes a blunt (i.e., not sharp) distal end <NUM> having an opening <NUM>. The cover <NUM> further includes a proximal end <NUM>. The cover <NUM> may have a generally tubular shape and defines a longitudinal bore extending from the distal end <NUM> to the proximal end <NUM>. The inner penetrator <NUM> and/or the outer penetrator <NUM> may be disposed within the opening <NUM> when the cover is in the first or extended position to protect a user or operator of the IO access device <NUM> (as well as a subject on which the device will be used) from being inadvertently stuck by the inner and/or outer penetrator tips.

The proximal end <NUM> of the cover <NUM> may include a plurality of resilient fingers <NUM> annularly disposed along its circumference, each finger including a respective ridge or nub <NUM> protruding radially outward therefrom. The proximal end <NUM> of the cover <NUM> may be slidably coupled to the manual driver <NUM> via a correspondingly shaped internal groove or recess <NUM> disposed between the inner penetrator hub <NUM> and the handle <NUM>. For instance, in implementations where the protective shield <NUM> has a generally tubular shape, the corresponding internal recess <NUM> is annularly disposed in the driver. More particularly, the respective ridges or nubs <NUM> disposed on the resilient fingers <NUM> of the cover <NUM> are operable to provide a friction fit within the recess <NUM> of the driver to maintain the cover in a desired position, such as in the extended position or in the retracted position. The cover <NUM> may be detached from the driver <NUM>, such that the driver can be used for peripheral insertion of the penetrator assembly into an intraosseous space.

In some implementations, the grip <NUM> and the inner penetrator hub <NUM> may be attached to each other through a bond created with an ultraviolet (UV) curable adhesive. In other implementations, the grip <NUM> and the inner penetrator hub <NUM> may be integral with each other (such as through injection molding), thus forming a single unitary structure. In still other implementations, the grip <NUM> and the inner penetrator hub <NUM> may be force coupled, or otherwise adhered to one another, while in other implementations, the grip <NUM> and the inner penetrator hub <NUM> may be removably coupled to each other such that they can be separated without destroying, damaging or otherwise impairing the function of either component for re-use. In still other implementations, the grip <NUM> may be coupled directly to the outer penetrator hub <NUM> such that there is no intervening inner penetrator hub <NUM>, and with the inner penetrator <NUM> being attached directly to the grip <NUM>.

The tip <NUM> of the inner penetrator <NUM> is pointed and configured to allow the IO access device <NUM> to be driven into an intraosseous space, such as intraosseous space <NUM>. The inner penetrator <NUM> fits closely within the passageway of the outer penetrator <NUM> such that the inner penetrator <NUM> prevents the outer penetrator <NUM> from becoming clogged with tissue (e.g., skin, bone, marrow) as the IO access device <NUM> is driven into an insertion site of a subject (e.g., a patient). The inner penetrator tip <NUM> and the outer penetrator distal end <NUM> may be ground together to form corresponding cutting surfaces in some implementations where both the inner penetrator <NUM> and the outer penetrator <NUM> comprise a suitable metal. In other implementations, the inner penetrator tip <NUM> and the outer penetrator distal end <NUM> may be ground separately to form corresponding cutting surfaces configured to penetrate bone and associated marrow. Once the IO access device <NUM> is properly positioned at the insertion site, the manual driver <NUM> can be disengaged from the outer penetrator hub <NUM> such that the proximal end <NUM> (which may take the form of a male Luer lock) is exposed and a conduit is formed from the outer penetrator hub <NUM> through the outer penetrator <NUM> to the intraosseous space. A fluid source may then be coupled to the proximal end <NUM> of the outer penetrator hub <NUM> to deliver fluid through the outer penetrator <NUM> and into intraosseous space.

<FIG> depict various views of a sternal locator <NUM> for use with the IO access device <NUM>. The locator <NUM> is operable to help a user locate an insertion site on the sternum of a patient and facilitate insertion of the IO access device <NUM> into the intraosseous space. The locator <NUM> comprises a circumferential collar <NUM> and a base <NUM> projecting from the circumferential collar <NUM>. The base <NUM> comprises a top surface <NUM> and an underside surface <NUM>. The base <NUM> also comprises an alignment feature <NUM>, as will be discussed in detail below.

The circumferential collar <NUM> comprises a collar contact surface <NUM> and an annular through-hole or passageway <NUM> extending through the locator. The collar <NUM> further comprises a plurality of longitudinally-oriented resilient locking tabs <NUM> that are spaced apart from each other (i.e., circumferentially-spaced apart from each other at <NUM> degree intervals). In some implementations, there may be three locking tabs <NUM>, as depicted in the figures. In other implementations, there may be more or fewer locking tabs <NUM> (e.g., <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or more tabs). The through-hole <NUM> extends from the collar contact surface <NUM> to the underside <NUM> of the base. The collar contact surface <NUM> is configured to contact the annular flange <NUM> at the distal end <NUM> of the skirt <NUM> to impede further insertion of the penetrator assembly into the intraosseous space, thus providing a depth stop for the IO access device. The collar contact surface <NUM> is an example of a proximal-facing surface adjacent a passageway configured to receive a penetrator of an IO access device.

The collar <NUM> is configured to couple the locator <NUM> to the IO access device <NUM>, and more particularly, the one or more locking tabs <NUM> of the collar <NUM> are configured to secure the locator <NUM> to the IO access device <NUM>. For example, each locking tab <NUM> has an inwardly-projecting portion 216i that includes a surface <NUM> that is configured to overlie a portion of the inner penetrator hub <NUM> (and, more specifically, the flange <NUM> at the distal end <NUM> of the skirt <NUM>) of the IO access device <NUM>. At least a portion of each surface <NUM> may be oriented at a non-zero (e.g., perpendicular) angle relative to the direction of insertion of the IO access device <NUM>. More particularly, each surface <NUM> may be configured with a shape that complements the shape of a portion of the flange <NUM> at the distal end <NUM> of the skirt <NUM> it will contact after the IO access device <NUM> is inserted into the intraosseous space, which portion may be on a proximally-facing surface of the flange <NUM>. As a result, the surfaces <NUM> are configured to resist or impede removal of the inner penetrator <NUM> after the inner and outer penetrators <NUM>, <NUM> are inserted into the intraosseous space.

Each locking tab <NUM> (and, more specifically, each vertical component 216v of each tab <NUM>) is configured to flex outward away from the center of the collar <NUM> as inwardly-tapered exterior surface 216t of the projecting portion 216i contacts a distally-facing surface of the flange <NUM> at the distal end <NUM> of the skirt <NUM>, then snap inward as the surface <NUM> passes over the flange <NUM>, thus locking the IO access device <NUM> in place. It should be appreciated that the number of locking tabs used may be adjusted to best suit the shape of the IO access device being used.

The locking tabs <NUM> are configured to stabilize the IO access device both by resisting any outward longitudinal movement of the IO access device (meaning movement out of the intraosseous space along the direction of insertion) as well as any movement that would otherwise result from the IO access device canting from side-to-side or otherwise moving laterally. The collar <NUM> also includes longitudinally-oriented elements <NUM> that have inwardly-tapered surfaces 256t and curved inner surfaces (which are shaped like the inside of a cylinder) <NUM>. These elements are taller than the locking tabs <NUM> and function to guide the IO access device to the proper location as it enters the space bounded by the collar <NUM>, which also helps to prevent damage to the tabs <NUM>. The longitudinally oriented elements <NUM> also help to resist any lateral pitching or movement of the IO device. Each element <NUM> includes at least one longitudinally-oriented rib <NUM> that serves to increase the rigidity (and tendency to resist lateral bending) of the element <NUM>. Each rib includes an enlarged portion that surrounds a portion of a bone probe <NUM>.

The alignment feature or notch <NUM> of the locator <NUM> is an arc-shaped portion of the base <NUM>. The alignment feature <NUM> is configured to approximate the shape of sternal notch <NUM> of a human patient and is operable to indicate proper placement of the locator <NUM>. The locator is properly located on the chest of a patient when it is placed over the sternum such that the sternal notch is visible and at least partially (and, preferably, completely) bounded by alignment feature <NUM>.

The most inwardly-curved portion of the alignment feature <NUM> is spaced a distance DA from the center of the through-hole <NUM> (that is, DA is the shortest distance between the hole <NUM> and the alignment feature <NUM>). In some implementations, DA may be about <NUM>. In other implementations, DA may range from about <NUM> to about <NUM>. The outer edge of the base <NUM> may be about <NUM> from the nearest location on the closest locking tab <NUM>, such that a distance DF may be about <NUM>. In other implementations, DF may range from about <NUM> to <NUM>. Some other implementations of the present locators <NUM> may not include the base <NUM>.

The locator <NUM> comprises a plurality of openings <NUM> in the underside <NUM> of the base <NUM>. For instance, <FIG> and <FIG> depict six openings <NUM>, although other implementations may have more or less openings (e.g., <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or more openings). A recess <NUM> extends from each opening <NUM> into a respective rib <NUM> of a corresponding longitudinally-oriented element <NUM>. Each recess <NUM> is configured to receive a respective bone probe <NUM>, as shown in <FIG>. Other implementations may comprise more or fewer recesses (and associated openings) configured to respectively receive more or fewer bone probes <NUM>.

As shown in <FIG>, each probe <NUM> comprises a pointed tip <NUM>, a plurality of circumferential grooves or notches <NUM>, and a proximal end <NUM>, where the notches <NUM> are closer to the proximal end <NUM> than to the tip <NUM>. The probes <NUM> may comprise stainless steel, though other suitable sterile or biocompatible materials (or materials capable of being made sterile before use on a patient) may be used. The proximal end <NUM> is configured to be inserted into the opening <NUM> and corresponding recess <NUM> of the locator <NUM>. In some implementations, the bone probes <NUM> may be fixed to the locator <NUM>, such as by being bonded to the locator <NUM> using UV-curable adhesive applied to the recess <NUM> and/or the grooves <NUM> and/or the proximal end <NUM> of the probe <NUM>. In other implementations, the bone probe <NUM> may be force fit through the opening <NUM> and into the recess <NUM> such that it is held in place by friction between the probe and the surface of the locator against which it is in contact with, thus forming an interference fit. In still other implementations, the probes <NUM> may be fixed to the locator <NUM> as part of an injection molding process or using epoxy. Each probe <NUM> may comprise any of various lengths and can extend, for example, approximately <NUM>-<NUM> millimeters from a proximal-facing surface adjacent a passageway (e.g., from the collar contact surface <NUM>).

<FIG> depict another implementation of bone probes 30a that are suitable for use with the locator <NUM>. Each probe 30a comprises a pointed tip 32a, a groove or notch 34a, and a proximal end 36a, where notch 34a is closer to the proximal end 36a than to the tip 32a. Each probe 30a may comprise stainless steel, though other suitable sterile or biocompatible materials (or materials capable of being made sterile before use on a patient) may be used. The proximal end 36a is configured to be inserted through the opening <NUM> and into the corresponding recess <NUM> of the locator <NUM>. Probes 30a may be fixed to the locator <NUM>, such as by being bonded to locator <NUM> using UV-curable adhesive applied to the recess <NUM> and/or the notch 34a and/or the proximal end 36a of the probe 30a. In other implementations, the probe 30a may be force fit in the opening <NUM> and the recess <NUM> such that it is held in place by friction between the probe and the surface of the locator against which it is in contact, thus forming an interference fit. In other implementations, the probes 30a may be fixed to the locator <NUM> as part of an injection molding process or using epoxy. The probe 30a may comprise any of various lengths and can extend, for example, approximately <NUM>-<NUM> millimeters from a proximal-facing surface adjacent a passageway (e.g., from the collar contact surface <NUM>).

<FIG> illustrates a stabilizer <NUM> configured to be placed on the chest of a subject (e.g., a human patient) at a location near the sternum <NUM> and aligned with the sternal notch <NUM>. The stabilizer <NUM> is also configured to ensure proper placement of an IO access device in the intraosseous space <NUM>. The stabilizer <NUM> comprises the locator <NUM>, the base of which is located between and coupled to a stabilizer dressing including a top sheet <NUM> and an adhesive patch <NUM>. Further, the top sheet <NUM> and the adhesive patch <NUM> are coupled to each other. The adhesive patch <NUM> comprises an adhesive configured to adhere the stabilizer <NUM> to a subject during use (e.g., to the skin on the chest of a human patient).

The top sheet <NUM> may comprise single-sided tape, such as <NUM> <NUM> polyethylene single coated tape. The top sheet <NUM> may be oriented such that the adhesive side of the tape couples top sheet <NUM> to the top surface <NUM> of the base <NUM> and to adhesive patch <NUM>. The adhesive patch <NUM> may comprise any standard medical grade adhesive. For example, the adhesive member may comprises double-sided tape, such as <NUM> <NUM> transparent polyethylene double coated tape. One side of the adhesive patch <NUM> is coupled both to underside <NUM> of base <NUM> and to top sheet <NUM>, while the other side of adhesive patch <NUM> is coupled to at least one liner (e.g., a release liner).

As shown in <FIG>, the adhesive patch <NUM> is coupled to a removable first liner <NUM> and a removable second liner <NUM>. The removable liners <NUM>, <NUM> cover the bottom adhesive side of the adhesive patch <NUM> (e.g., to prevent the stabilizer <NUM> from undesired sticking). When the stabilizer <NUM> is ready to be used, the liners <NUM>, <NUM> can be removed by a user and the stabilizer <NUM> can be placed on the chest of a patient.

Some implementations of the stabilizer may not include top sheet <NUM> or adhesive patch <NUM>. For example, the stabilizer <NUM> may lack any adhesive features for coupling the template to the chest of a patient. In still other implementations, the underside <NUM> of the base <NUM> may be coated with an adhesive directly applied to the locator <NUM> (that is, without requiring a tape layer as discussed above). In such implementations, one or more liners may be coupled directly to the locator <NUM> to prevent undesired sticking. Implementations of the stabilizer that include an adhesive, such as one applied directly to the underside of the flange of the stabilizer or one on the bottom (distal) surface of an adhesive member, may be configured to adhere to skin on a subject patient.

<FIG> depicts an intraosseous access assembly comprising the IO access device <NUM> and the locator <NUM> prior to use on a patient (top layer <NUM> and adhesive patch <NUM> have been omitted for clarity). The locator <NUM> is operable to locate a preferred location for the IO access device <NUM> to be inserted (e.g., driven) into the sternum of a patient, i.e., by using the alignment feature <NUM> as previously described in detail above. The locator <NUM> is further configured to guide insertion of the IO access device <NUM> into the intraosseous space, i.e., by using the cover <NUM> as a guide for passing the penetrator assembly of the IO access device through the through-hole <NUM> of the locator and into the intraosseous space of the patient. Prior to use on a patient, the cover <NUM> is operable to provide sharps protection from the distal ends of the inner and outer penetrators. The cover <NUM> is also operable to provide sharps protection from the distal end of the inner penetrator when the driver is decoupled from the outer penetrator after accessing the intraosseous space.

<FIG> depict the intraosseous access assembly comprising the IO access device <NUM> coupled to the locator <NUM> while in use on a human patient (top layer <NUM> and adhesive patch <NUM> have been omitted for clarity). D<NUM> is the distance from the collar contact surface <NUM> to the top surface <NUM> of the base <NUM>. D<NUM> includes the thickness of the base <NUM> and any adhesive on the underside <NUM> or any adhesive patch <NUM> (not shown). D<NUM> is the distance from the underside <NUM> or any adhesive or adhesive member attached to the underside <NUM> to the tip <NUM> of the bone probe <NUM>. D<NUM> is the distance from bone probe tip <NUM> to the tip <NUM> of the inner penetrator <NUM>. Therefore, the overall exposed length of the penetrator assembly (the portion of the inner and outer penetrators <NUM>, <NUM> that extends beyond the outer penetrator hub <NUM>) is D<NUM>+D<NUM>+D<NUM>+D<NUM>.

In some implementations, D<NUM> may be about <NUM>, D<NUM> may be about <NUM>, D<NUM> may be about <NUM>, and D<NUM> may be about <NUM>; and therefore, about <NUM> of the penetrator assembly may be exposed or protrude beyond the outer penetrator hub <NUM>. Further, the bone probes <NUM> may be exposed or protrude beyond the underside <NUM> of the locator <NUM> by about <NUM>. In some implementations, the inner penetrator <NUM> may protrude about <NUM> beyond the outer penetrator <NUM>. When the IO access device <NUM> is coupled to the locator <NUM> such that the tabs <NUM> are in a locked position (and the surfaces <NUM> bear against the upper surface of the flanged portion <NUM> of the distal end <NUM> of the skirt <NUM>), the inner penetrator <NUM> may extend about <NUM> to <NUM> beyond each of the plurality of bone probes <NUM>. Depending on the application, the exposed portions of inner and outer penetrators <NUM>, <NUM> and the bone probes <NUM> may be lesser or greater than what is shown and described. For instance, the inner penetrator <NUM> and the bone probes <NUM> may be shorter when the sternal locator <NUM> and the IO access device <NUM> are intended for use on infants or children (and the inner penetrator <NUM> may extend a shorter distance beyond probes <NUM>). Further, the inner penetrator <NUM> and the probes <NUM> may be longer (and inner penetrator <NUM> may extend a greater distance beyond probes <NUM>) when the sternal locator and IO access device are intended for use on obese patients, large patients, or patients with a thicker than normal sternum. In other implementations, D<NUM> may be about <NUM>, D<NUM> may be about <NUM>, D<NUM> may be about <NUM>, and D<NUM> may be about <NUM>; such that about <NUM> of the penetrator assembly may be exposed or protrude beyond the outer penetrator hub <NUM> and/or about <NUM> of probes <NUM> protrudes beyond the underside <NUM> of the locator <NUM>. Any dimension listed herein as "about" may also be substantially (including exactly) equal to the given value.

To use the sternal locator <NUM>, a user first locates the sternal notch <NUM> of a patient by feeling for the U-shaped cavity above the sternum, below the throat, and between the clavicles. The user then aligns the alignment feature <NUM> of the locator with the sternal notch <NUM>, ensuring that the balance of the sternal locator is positioned over the patient's sternum. With the sternal locator <NUM> thus properly aligned, the user then applies pressure to the sternal locator <NUM>, such that the bone probes <NUM> penetrate skin <NUM> and muscle <NUM>, until the bone probes touch the anterior compact bone <NUM> (the top surface of the sternum). Thus, the bone probes <NUM> provide a depth stop for the locator <NUM> once they contact bone. The bone probes <NUM> may penetrate into the anterior compact bone <NUM> by some marginal distance, such as about <NUM> to about <NUM>, but do not penetrate into the intraosseous space <NUM>. The user then removes the removable liners <NUM>, <NUM> of the stabilizer dressing and presses the adhesive patch <NUM> against skin <NUM>, thus ensuring that adhesive patch <NUM> is adhered to the skin of the patient.

The thickness of skin <NUM> and subcutaneous tissue <NUM> may be equal in thickness to D<NUM>, the exposed length of the bone probes <NUM>. However, the thickness of skin <NUM> and subcutaneous tissue <NUM> can vary widely depending on the patient. Thus, in some patients, the length of the probes <NUM> may exceed the tissue thickness such that the locator base <NUM> is not flush with the skin <NUM>, and portions of the probes <NUM> are therefore exposed. In such instances, the adhesive layer <NUM> provides an additional stabilizing effect by affixing the sternal locator <NUM> to the patient's chest.

Once the stabilizer <NUM> has been securely affixed to the patient's chest, the user then introduces the distal portion of the IO access device <NUM> (which includes the inner penetrator tip <NUM>, the outer penetrator distal end <NUM>, and the distal end of the cover <NUM>) into the through-hole <NUM> in the base <NUM> of the locator <NUM>. The through-hole <NUM> includes a complimentary annular shape to that of the tubular cover <NUM> so that the cover is guided through the through-hole when inserted. The user applies pressure and rotates, twists or reciprocates IO device <NUM> (which may be back and forth, but not necessarily all the way around, such that the driving movement may be characterized as reciprocating, twisting, or non-rotational (meaning one complete revolution is not utilized)) until the inner penetrator <NUM> and the outer penetrator <NUM> pierce the skin <NUM>, the subcutaneous tissue <NUM>, and the anterior compact bone <NUM>. During this insertion procedure, the distal end <NUM> of the cover <NUM> contacts the skin <NUM> without penetrating it since the distal end is blunt (i.e., not sharp). The cover <NUM> then moves from the extended position to the retracted position as the inner and outer penetrators are inserted into the intraosseous space. In some instances, the intraosseous access device <NUM> may be used without the locator <NUM> at peripheral insertion site, such as a patient's humerus or tibia. During such a peripheral insertion procedure, the distal end <NUM> of the cover <NUM> contacts the skin <NUM> without penetrating it since the distal end is blunt (i.e., not sharp). The cover <NUM> is operable to move from the extended position to the retracted position as the inner and outer penetrators are inserted into the intraosseous space.

As previously described, the collar <NUM> is, and more specifically the one or more resilient locking tabs <NUM> of the collar <NUM> are, configured to couple (e.g., secure) the locator <NUM> to the IO access device <NUM>. The IO access device <NUM> is properly positioned when the surfaces <NUM> of the locking tabs <NUM> fully engage (or are in contact with) the flange <NUM> of the distal end <NUM> of the skirt <NUM>. The rigidity of the resilient locking tabs <NUM> serves to stabilize the IO access device to which the sternal locator is coupled, both by resisting any outward longitudinal movement of the IO access device (i.e., movement out of the intraosseous space along the direction of insertion) as well as any movement that would otherwise result from the IO access device canting from side-to-side or otherwise moving laterally. The collar <NUM> also includes longitudinally-oriented elements <NUM> that are taller than the tabs <NUM> and which are operable to guide the IO access device to the proper location as the flange <NUM> of the distal end <NUM> of the inner penetrator hub enters the space bounded by collar <NUM>, which also helps to prevent damage to tabs <NUM>, and further helps to resist any lateral pitching or movement of the IO access device during an insertion procedure. Each element <NUM> includes a pair of longitudinally-oriented ribs <NUM> on opposing sides of the element that serve to increase the rigidity (and tendency to resist lateral bending) of the element <NUM>. Each rib <NUM> is hollow to receive and surround a portion of a respective bone probe <NUM>.

In some aspects, an audible sound (e.g., a click) may be heard as the tabs <NUM> pass over the flanged portion <NUM> of the distal end <NUM> of the skirt <NUM> and snap into place. Furthermore, the user may feel the IO access device passing the tabs <NUM> because the force required to advance the device will be reduced (thus, the user will feel a tactile response of the IO access device "snap" into place). Introducing the IO access device <NUM> into the patient in this manner may be described as non-surgically introducing (or inserting) the IO access device, or introducing (or inserting) the IO access device without first making an initial incision for the IO access device with a different cutting tool (such as a scalpel). The force that is required to drive the IO access device into locking engagement with the locator may be greater than the force be required to drive the stabilizer through the skin and subcutaneous tissue and into contact with anterior compact bone in most patients.

As shown in <FIG>, the driver <NUM> (including the grip <NUM>, the inner penetrator hub <NUM> and associated inner penetrator <NUM>, and the cover <NUM>) may then be removed from the outer penetrator hub <NUM>. For instance, the inner penetrator hub <NUM> may be decoupled from the outer penetrator hub <NUM> by rotating the grip <NUM> in a counterclockwise direction to disengage the threaded surfaces <NUM>, <NUM> of the respective outer and inner penetrators. This allows the user to withdraw the inner penetrator <NUM> from the outer penetrator <NUM> while the outer penetrator remains disposed within the intraosseous space. A conduit is thus formed from the open proximal end <NUM> of the outer penetrator hub <NUM> through an opening at the outer penetrator distal end <NUM>, which is in direct fluid communication with intraosseous space <NUM>. In some implementations, a flexible outer penetrator may be utilized so that it may be manipulated and secured to the patient after the stabilizer assembly is removed in order to provide a lower profile (i.e., by bending the outer penetrator down to secure it against the skin).

A fluid source may then be coupled to the proximal end <NUM> of the outer penetrator hub <NUM> for delivery of fluid (e.g., blood or medicine) to intraosseous space <NUM> or aspiration of fluid from the intraosseous space. Further, upon removal of the driver <NUM> from the outer penetrator hub <NUM> and the locator <NUM>, the cover <NUM> is operable to move back to the extended position from the retracted position to provide sharps protection from the distal tip <NUM> of the inner penetrator <NUM>.

The sternal locator <NUM> is also configured to be withdrawn from the patient's chest while the outer penetrator <NUM> remains disposed within the intraosseous space. In particular, as the locator is withdrawn from the patient, the through-hole <NUM> passes over the outer penetrator hub <NUM> without dislodging the outer penetrator <NUM> from the intraosseous space. The diameter of the through-hole <NUM> of the locator <NUM> is larger than the diameter of the outer penetrator hub <NUM>, such that the locator can be freely lifted over the hub without bumping into it. After the locator has been withdrawn from the patient, the bone probes <NUM> may be inserted into penetrable material of a sharps container.

A kit may be provided that includes a package (e.g., a flexible package, such as one that does not include a rigid plastic tray) comprising at least one of the present sternal locators, one of the present stabilizers, one of the present sharps containers, and, one of the disclosed IO access devices, as well as instructions for use, which instructions may be provided on the outside of the package, on one of the aforementioned components, and/or on an insert contained within the package. Further, non-limiting examples of suitable materials for the present locators, grips, and hubs described above may include injection moldable plastics, such as polycarbonate. A non-limiting example of a suitable material for the present inner penetrator, outer penetrator, and probes described above may include stainless steel, such as 304V stainless steel.

Claim 1:
An apparatus (<NUM>) for accessing an intraosseous space within a bone of a patient, the apparatus comprising:
a penetrator assembly (<NUM>,<NUM>) having a sharp penetrating end configured to penetrate the bone and associated bone marrow;
a manual driver (<NUM>) coupled to the penetrator assembly, the manual driver including a handle (<NUM>) operable to manually drive the penetrator assembly into the bone and associated bone marrow;
a protective shield (<NUM>) having a distal end (<NUM>) and a proximal end (<NUM>), the protective shield slidably coupled to the handle and defining a longitudinal hollow passageway extending between the distal end and the proximal end, the proximal end of the protective shield including a resilient finger (<NUM>); and
an internal recess (<NUM>) within the handle (<NUM>), the internal recess configured to slidably receive the proximal end of the protective shield;
where the protective shield is operable to move between an extended position in which the sharp penetrating end of the penetrator assembly is disposed within the longitudinal hollow passageway of the protective shield to provide sharps protection, and a retracted position in which the sharp penetrating end of the penetrator assembly is disposed outside the longitudinal hollow passageway of the protective shield to permit penetration of the penetrator assembly into the intraosseous space, and
wherein the resilient finger includes an outwardly protruding ridge (<NUM>) configured to provide a friction fit within the internal recess to maintain the protective shield in a desired position.