Patent Description:
In general, it can be difficult to securely attach articles to surfaces without resorting to the use of secondary (adhesive) fixings and the like. For example, the medical treatment of patients commonly involves the use of percutaneously inserted medical cannulas such as medical lines or catheters to monitor vital functions, administer high volume or aggressive medications, to direct fluids into the bloodstream, or facilitate access for dialysis. However, any catheter or other medical article inserted in the human body for medical treatment is susceptible to serious complications such as migration, dislodgement, thrombosis, occlusion and infection. For example, accidental dislodgement can occur in between <NUM>% and <NUM>% of catheters and can arise when a catheter experiences a sudden external force from being pulled or accidentally caught by another object. Moreover, accidental motion or "micro-pistoning" can occur with cannulas i.e. movement of a catheter in and out of a vein in a pistoning action. Even a small amount of catheter motion can be a contributing factor to negative complications in patients with central venous catheters or any other cannula.

Accordingly, in an attempt to minimise cannula movement and micro-pistoning clinicians typically employ adhesive bandages, plasters or surgical tape to attach catheters and the like to a patient in a stationary manner.

The use of adhesive bandages, plasters and the like to hold cannulas in place can result in a significant build-up of adhesive residue on the cannulas, their associated tubing and patients - particularly where regular re-positioning of the cannula is required e.g. in dialysis patients. Residue build-up on catheters and tubing can be particularly difficult to remove giving rise to increased infection risks while residue build-up can also weaken the structure of catheters.

Moreover, such ad-hoc and improvised methods are generally unreliable and undesirable movement and micro-pistoning of medical articles can still take place to the detriment of the patient.

Dedicated securement devices for catheters are also known. However, the known devices also suffer from a number of disadvantages. For example, many known devices secure catheters significant distances from the catheter entry site - a distance of <NUM> being typical. As a result, while the securement device may protect the catheter from catastrophic dislodgment if pulled, hysteresis created between the entry site and the securement device can still be sufficient to allow micro-pistoning to occur.

Other known securement devices can also be invasive e.g. by employing two small metallic legs which are implanted into the skin of the patient at the entry site to secure the securement device in situ. However, such an invasive approach is currently only compatible with peripherally inserted central (PICC) catheters and cannot be used for other applications.

<CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT> also describe various dedicated securement devices for catheters and the like. However, as with the ad hoc devices described above, the dedicated securement devices of the prior art cannot be easily repositioned without giving rise to adhesive residues. <CIT> and <CIT> also describe catheter fixing devices in which catheters must be squeezed to be held in place which can interfere with the performance of the catheter. <CIT> describes a securement device according to the preamble of Claim <NUM> in which the slots of the securement device are provided in different sizes to accommodate different size tubes. Moreover, all the dedicated securement devices of the prior art rely on relatively complex catheter holding structures and still fail to effectively eliminate micro-pistoning while the complex structures employed limit the use of the prior art securement devices to particular catheter types and sizes.

Accordingly, the invention provides a securement device as set out in the claims.

Preferably, the base defines a channel for receiving the article.

In one embodiment, the base comprises a substantially cylindrical base.

Preferably, the slot comprises an article receiving portion complementary with the channel for receiving the article in the article receiving position.

The helical slot portions comprise an upright slot element (i.e. substantially orthogonal to the surface) and a substantially horizontal slot element (i.e. substantially parallel to the surface) contiguous with the upright slot element in the sidewall.

Preferably, the mounting comprises a screw mounting to impart a downward compressive force on an article in the article gripping position. More preferably, the screw mounting comprises a thread on the base.

Suitably, the thread comprises first and second oppositely disposed substantially helical threads on the base. Preferably, the thread comprises a groove-like thread. Optionally, the screw mounting comprises at least one lug on the cap insertable in the thread.

Preferably, the thread further comprises at least one stop abuttable against the at least one lug.

Optionally, the securement device further comprises a lock to prevent unauthorised or accidental release of the securement device. Preferably, the lock comprises a push to release lock in the cap such as a child proof lock of the type found on medicine containers.

In a further embodiment of the invention, the securement device comprises a secondary fixing clasp for clasping the article in place.

Preferably, the secondary fixing clasp is mounted on the anchor pad. More preferably, the secondary fixing clasp is mounted on a secondary anchor pad portion spaced apart from a primary anchor pad portion. Most preferably, the primary anchor pad portion is connected with the secondary anchor pad portion by an anchor pad web portion extending between the primary anchor pad portion and the secondary anchor pad portion.

Preferably, the anchor pad comprises an adhesive for adhering the securement device to a surface.

Suitably, the anchor pad comprises a release film on the adhesive.

In a preferred embodiment of the invention, the securement device comprises a securement device for attaching a medical article to a patient.

The base can comprise a substantially cylindrical base defining a channel for receiving the article. In a preferred variant, the cap comprises a slot for receiving an article in the article receiving position and gripping the article in the article gripping position.

The securement device of the invention securely holds articles in place on a surface and is adapted to reversibly hold (elongate) cylindrical or tubular articles in place on surfaces so that the articles can be repositioned as required without giving rise to a build-up of adhesive residues on the articles.

The securement device is particularly adapted to hold medical articles such as catheters, lines, intravenous drips, surgical drains and cables such as E. cables in position on a patient. The securement device can be used to position and reposition the medical articles as required without employing adhesive bandages and plasters so that no build-up of adhesive residue occurs on the medical articles. Accordingly, the securement device of the invention minimises the risk of infection caused by adhesive residues whilst also ensuring that the structural integrity of the medical article is maintained. The securement device is therefore particularly suitable for use with medical articles requiring frequent repositioning e.g. dialysis catheters.

The securement device of the invention also inhibits axial motion such as micro-pistoning of the medical article. More particularly, the radial force applied by the rotatable securement device of the invention to tubular medical articles such as catheters eliminates the need to use adhesive bandages, plasters or surgical tape, whilst providing a rigid securement to prevent movement and/or dislodgment. The dedicated medical line securement device therefore reduces the risk of related complications by reducing movement such as micro-pistoning whilst allowing consistent and rapid access to the line by clinicians. The securement device of the invention can also be positioned adjacent entry sites on patients so that catheter hysteresis which can give rise to micro-pistoning is reduced or eliminated.

The jaw-like continuously tapered slot of the securement device for gripping tubular articles allows the securement device to grip a range of tubing/cabling sizes so that non-standard tubing/cabling can be gripped i.e. no specific tubing size graduation is required. This also allows for confident securing of tubular articles which may have swelled or changed dimension from use overtime and which, as a result, may not adhere to their original manufactured size specification - this can be a particular problem with catheters. Accordingly, in contradistinction with known dedicated securement devices, a securement device of the invention can function effectively with a range a tubular articles.

In addition to the radial force applied by the tapered slot, downward rotational movement of the screw cap on the base of the securement device of the invention results in a downward compressive force on articles so that the articles are urged or pulled tightly into the base to further enhance secure gripping of the article.

The securement device is also suitable for use with other cylindrical or tubular non-medical articles such as computer cabling, machine tubing, electrical cabling, hydraulic/pneumatic cabling and oil cabling where an effective (repositionable) grip is required that does not damage the articles and does not rely on the use of adhesives.

The securement device of the invention is also of relatively simple construction with only three components making it easy and cost-efficient to manufacture.

As shown in <FIG> of the accompanying drawings, a first embodiment of a securement device <NUM> in accordance with the invention for securely attaching a medical article such as a catheter <NUM> to a patient is generally made up of an anchor pad <NUM> for placing the securement device <NUM> on the patient, a base in the form of a substantially cylindrical base <NUM> on the anchor pad <NUM> and a screw cap <NUM> rotatably mountable on the base <NUM> at a (screw) mounting <NUM> defined between the base <NUM> and the screw cap <NUM> between a catheter receiving position (shown in <FIG>, <FIG> and <FIG>) and a catheter gripping position (shown in <FIG>, <FIG>, <FIG> and <FIG>) in which radial pressure is applied to the catheter <NUM> placed in the securement device <NUM> to securely hold the catheter <NUM> and prevent micro-pistoning of the catheter <NUM>. The screw cap <NUM> can be moved repeatedly between the catheter receiving and catheter gripping positions so that the catheter <NUM> can be positioned, secured, repositioned and re-secured as needed without requiring the use of adhesive plasters, dressings and the like. As a result, adhesive residues do not build up on the catheter <NUM> so that the risk of infection is minimised and the structural integrity of the catheter <NUM> is not compromised.

The cylindrical base <NUM> is made up of a circular bottom wall <NUM> in contact with the anchor pad <NUM>, a sidewall <NUM> upstanding from the bottom wall <NUM> and a top face <NUM>. The top face <NUM> is provided with a transverse U-shaped elongate channel <NUM> to sub-divide the sidewall <NUM> into a first sidewall portion <NUM> and an opposite second sidewall portion <NUM>. The U-shaped channel <NUM> receives and holds a catheter <NUM> in the securement device <NUM> in use.

Externally, the first and second sidewall portions <NUM>,<NUM> are each provided with respective first and second oppositely disposed substantially helical groove-like threads <NUM>,<NUM> which form part of the mounting <NUM> defined between the base <NUM> and the screw cap <NUM>. Each thread <NUM>,<NUM> has an upright thread portion <NUM> and a lower horizontal thread portion <NUM> contiguous with the upright thread portion <NUM>. The lower horizontal portion <NUM> of each thread <NUM>,<NUM> is provided with spaced-apart stops <NUM> to provide resistance to prevent the screw cap <NUM> from free spinning on the base <NUM> and to provide haptic feedback during rotatable engagement of the screw cap <NUM> with the base <NUM>. This shall be explained more fully below.

The screw cap <NUM> is complementary in size and shape with the base <NUM> and has a circular lower rim <NUM> with a circular sidewall <NUM> upstanding therefrom towards a top wall <NUM>. The circular lower rim <NUM> defines a base opening <NUM> into which the base <NUM> is received by the screw cap <NUM> during mounting of the screw cap <NUM> on the base <NUM>.

A tapered catheter slot <NUM> for receiving and gripping a catheter <NUM> is defined in the screw cap sidewall <NUM> and top wall <NUM>. The catheter slot <NUM> is made up of a transverse catheter receiving portion <NUM> defined in the top wall <NUM> complementary with the transverse U-shaped catheter receiving channel <NUM> in the base <NUM> and first and second oppositely disposed substantially helical slot portions <NUM>,<NUM> for gripping a catheter <NUM> with a radial force defined in the sidewall <NUM>. The helical slot portions <NUM>,<NUM> are each made up of an upright slot element <NUM> and a substantially horizontal slot element <NUM> contiguous with the upright slot element <NUM> defined in the cap sidewall <NUM>. The horizontal slot elements <NUM> are continuously tapered towards a slot end <NUM> i.e. the catheter slot <NUM> narrows towards the slot end <NUM> so that the securement device <NUM> can accommodate and securely grip catheters <NUM>, lines and the like of varying sizes in a jaw-like manner.

Internally, the screw cap <NUM> is provided with two oppositely disposed lugs <NUM>,<NUM> on the sidewall <NUM>. The lugs <NUM>,<NUM> form part of the mounting <NUM> between the base <NUM> and the cap <NUM>. More particularly, the lugs <NUM>,<NUM> are insertable in and co-operable with the first and second helical threads <NUM>,<NUM> respectively defined in the sidewall <NUM> of the cylindrical base <NUM> to allow rotatable mounting of the screw cap <NUM> on the base <NUM>. As indicated above, the stops <NUM> in the lower horizontal thread portion <NUM> abut the lugs <NUM>,<NUM> to provide resistance to prevent free spinning of the screw cap <NUM> on the base <NUM> and to provide haptic feedback when rotating the screw cap <NUM> on the base <NUM>. The spaced apart stops <NUM> co-operate with the lugs <NUM>,<NUM> to fix the screw cap <NUM> in position on the base <NUM> and allow for the securement device <NUM> to be size adjusted in accordance with the size of catheter <NUM> (or other article) placed in the securement device <NUM>.

Externally, the screw cap <NUM> is provided with two oppositely disposed finger grips <NUM>,<NUM> on the screw cap sidewall <NUM> to facilitate manual gripping and rotation of the screw cap <NUM>.

The anchor pad <NUM> of the securement device <NUM> is of conventional construction and has an adhesive layer <NUM> for adhering the anchor pad <NUM> to a patient. The adhesive layer <NUM> can be protected with a release film prior to use.

In use, the anchor pad <NUM> with the base <NUM> is placed on a patient's skin <NUM> as required. With the rotatable screw cap <NUM> in the catheter receiving position shown in <FIG> and <FIG> (i.e. with the transverse catheter receiving portion <NUM> of the slot <NUM> in the screw cap <NUM> co-axially aligned with the transverse U-shaped catheter receiving channel <NUM> in the base <NUM>), a catheter <NUM> is inserted into the catheter receiving channel <NUM> (see <FIG>). The screw cap <NUM> is then gripped by a clinician at the grips <NUM>,<NUM> and rotated clockwise through <NUM>° as shown in <FIG> and <FIG>. The oppositely disposed helical catheter slot portions <NUM>,<NUM> of the catheter slot <NUM> therefore both slidably engage the catheter <NUM> in a jaw-like manner to apply radial pressure to the catheter <NUM> and securely grip the catheter <NUM>. The catheter <NUM> is therefore gripped twice at two spaced apart locations by the securement device <NUM>.

As shown particularly in <FIG>, rotation of the screw cap <NUM> on the base <NUM> causes the lugs <NUM>,<NUM> to travel downwards on the base <NUM> in the helical first and second threads <NUM>,<NUM> so that the screw cap <NUM> also applies a downward compressive force to the catheter <NUM> to urge the catheter <NUM> into the U-shaped channel <NUM> in the base <NUM> to further enhance gripping of the catheter <NUM>. The downward distance, α, travelled by the screw cap <NUM> on the base <NUM>, and hence the compressive force applied to the catheter <NUM>, is determined by the dimensions of the securement device. However, a distance, α, of about <NUM> creates sufficient compressive force for most applications.

As indicated above, the stops <NUM> on the base <NUM> co-operate with the lugs <NUM>,<NUM> to prevent separation of the base <NUM> and the screw cap <NUM> whilst holding the screw cap <NUM> in place on the base <NUM> during application of the compressive force and providing haptic feedback during operation.

The above process is reversed in order to release the catheter <NUM> without damage to the catheter <NUM>.

<FIG> and <FIG> show a second embodiment of a securement device <NUM> of the invention in which the securement device <NUM> has a secondary fixing clasp <NUM> on the anchor pad <NUM> for clasping and tidying a catheter <NUM> (not shown) in place on the securement device <NUM>. The cylindrical base <NUM> and the screw cap <NUM> are as previously described in relation to the securement device <NUM> of <FIG> and like numerals indicate like parts.

In the present embodiment, the anchor pad <NUM> is shaped and contoured to define a primary anchor pad portion <NUM> on which the cylindrical base <NUM> of the securement device <NUM> is mounted and a secondary anchor pad portion <NUM>, on which the secondary fixing clasp <NUM> is mounted, spaced apart from the primary anchor pad portion <NUM>. The primary anchor pad portion <NUM> is connected with the secondary anchor pad portion <NUM> by a wave-shaped anchor pad web portion <NUM> which extends between the primary anchor pad portion <NUM> and the secondary anchor pad portion <NUM> and spaces the fixing clasp <NUM> a set distance from the cylindrical base <NUM>.

The fixing clasp <NUM> has a fastener <NUM> for detachably fastening a catheter, or other tubular article, in the fixing clasp <NUM>. In the present embodiment, the fastener <NUM> is made up of two oppositely disposed push-fit notches <NUM>,<NUM> defined in the fixing clasp <NUM> for holding catheters and the like. Catheters and the like are therefore clasped in the secondary fixing clasp <NUM> in addition to being secured between the base <NUM> and screw cap <NUM> of the securement device <NUM> so that the articles enjoy a double grip to further minimise movement of articles held in the securement device <NUM>.

As indicated above, catheters and the like can be positioned and secured, repositioned and re-secured, repeatedly with the securement device <NUM> without requiring the use of adhesive plasters, dressings and the like so that adhesive residues do not build-up on the catheter <NUM>. Use of the securement device <NUM> therefore minimises infection risk and ensures that the structural integrity of the catheter <NUM> is maintained.

The improved grip achieved by the securement device <NUM> of the invention prevents unwanted dislodgement of the catheter <NUM> and micro-pistoning in use.

If desired, the securement device <NUM> can be provided with a lock to prevent unauthorised or accidental release of the securement device e.g. outside a clinical setting or during movement. A suitable lock is a push to release lock incorporated into the securement device <NUM> requiring a pushing down action on the screw cap <NUM> before rotation to release the screw cap <NUM> from the base <NUM>. Suitable lock mechanisms are to be found in the child-proof locks of medicine bottles and the like.

Claim 1:
A securement device (<NUM>) for attaching an article (<NUM>) to a surface (<NUM>) comprising:
an anchor pad (<NUM>) attachable to a surface (<NUM>);
a base (<NUM>) on the anchor pad (<NUM>) for receiving the article (<NUM>), and
a cap (<NUM>) mountable on the base (<NUM>) at a mounting (<NUM>) defined between the base (<NUM>) and the cap (<NUM>), the cap (<NUM>) being rotatable on the base (<NUM>) between an article receiving position and an article gripping position and the cap (<NUM>) comprising a slot (<NUM>) for receiving an article (<NUM>) in the article receiving position and gripping the article (<NUM>) in the article gripping position, characterised in that the slot (<NUM>) comprises first and second oppositely disposed substantially helical slot portions (<NUM>,<NUM>) in a sidewall (<NUM>) of the cap for gripping an article with a radial force in the article gripping position,
wherein the helical slot portions (<NUM>,<NUM>) comprise an upright slot element (<NUM>) and a substantially horizontal slot element (<NUM>) contiguous with the upright slot element (<NUM>) in the sidewall (<NUM>), and
wherein the substantially horizontal slot elements (<NUM>) continuously taper towards a slot end (<NUM>) in the sidewall.