The present invention relates generally to syringes and particularly to a syringe marking system which may include a template for visualization and/or application of custom markings to the syringe to assist in reducing errors inherent in the visualization of often very small index markings, and the associated difficulties inherent in accurately aligning the plunger with these markings, to ensure the volumetric accuracy in delivering the required dosages in either single or repeated used of a syringe. The same principles can be applied to other non-medical syringe uses, for example, in industrial processes.
Patients with chronic illnesses such as diabetes who require regular injection will, sometimes against medical advice, use a hypodermic syringe for injecting themselves on a number of occasions rather than the single syringe use which is generally recommended. Fortunately, this practice if it is carried out with care, does not result in an unusual number of infections. This may be the reason why it has been estimated that diabetic patients on average will use the same syringe for multiple injections.
For patients with a stable disease, it is often necessary to inject with a standard dose of insulin on numerous occasions. Because an insulin syringe is physically small (1 ml. or less), reading the index markings both linear and numerical can be difficult. Each time the syringe is filled, there is a possibility that a misreading of the index markings will occur and the wrong dose delivered. This situation could be alleviated if a syringe barrel is custom marked with a line of greater thickness or length corresponding to the much smaller index markings already on the syringe and at the level of the dose required. Large easily read numerical marks can also be applied by hand to identify the applied linear index marking. Assuming each syringe is customized for a specific dose each time insulin is drawn into that syringe, the plunger stopper may be aligned with this more easily seen line applied by hand to the barrel rather than the much smaller index markings printed on the barrel during manufacture. As the index markings take up approximately one half of the circumference of the barrel there is ample room on the remainder of the barrel to draw a custom marking line. It should be emphasized that enhancing the ability to accurately draw up the medication dose repeatedly to the same level should not be confused with the recommendations that a single use syringe should not be used multiple times. However, the reality is that diabetic patients typically use the same syringe for multiple injections and any method of simplifying the accurate drawing up of a dose of medication would presumably be welcome, reducing the risk of error and improving safety for the diabetic patient.
It should also be noted that diabetic patients will frequently have poor eyesight, due to diabetic retinopathy and visualization of the index markings on the syringe barrel may be very difficult for them. If a much more easily visualized mark or line is applied to the barrel, even possibly by a third party with better eyesight, this would allow patients to draw up their own medication repeatedly and more accurately even in the circumstance of poor eyesight.
U.S. Pat. No. 6,315,760 issued Nov. 13, 2001, of common assignee herewith, discloses a syringe having a white or contrasting write-on stripe applied to the syringe barrel to enhance the visualization of index markings and also to allow writing on this stripe. It will be appreciated that this contrasting stripe will enhance the ability to apply dose markings. However, not all syringe barrels have a contrasting stripe and it may be desirable to apply a custom dose line with a light colored or other contrasting colored marking pen. Fluorescent or other enhancements may also be applied and by a mechanical device rather than by hand.
This disclosure relates to a method of accurately applying custom markings such as a line to the barrel of a syringe to allow accurate filling of the syringe to a predetermined dose or more easily visualizing and identifying existing index markings present on a syringe during filling of the syringe. The accurate filling of a syringe involves performing visual and mechanical tasks simultaneously often with very small syringes. This can be difficult particularly for patients required to self inject who may have visual, cognitive or motor impairment. Accordingly, a type of template or dosage marker may be employed to indicate or to enable application of additional custom markings to simplify and enhance accuracy and speed of drawing up the desired dose of medication by the patient or caregiver. In one embodiment, the refractive index of a plastic or other template material may also provide magnification of the index markings enabling accurate visualization of the desired dose and permitting the easier application of custom markings to the barrel at the desired dose level,
Preferred components of the present invention include a dosage collar with certain properties which can be applied to the syringe and moved along the axis and aligned with the index markings present on the conventional syringe. The collar may contain an index line itself or alternatively one of the two borders of the collar can be used to align with the index markings. If desired a pen with particular characteristics can also be used to allow marking on the barrel, (or any suitable writing instrument if the write-on stripe is present). The template is movable axially along the barrel and then fixed to enable the pen to apply the custom mark. The collar therefore is movable and may be fixed at a selected location along the barrel to allow it to be used as a dosage marker or template for marking the barrel. The template may be formed of elastomeric or flexibly resilient material or with various clamping and release methodologies. The template can be set at a selected dose location along the barrel using the index markings or borders of the collar or cutouts in the collar. The template fits snugly about the barrel and, once positioned, resists movement, thereby enabling a pen or other writing instruments to be placed against the template for use as a guide for drawing the custom line or other mark on the barrel as described above.
The collar may also have a cutout on either side to allow visualization of the index markings or, alternatively, to permit the tip of the pen to be inserted into the cutout for drawing the marking on the barrel. In one embodiment some magnification using the refractive index of the material of the template, e.g. plastic, may be desirable to enhance visualization of the index markings
The collar or template may be permanently applied to each syringe or moveable from one syringe to another. In addition to referencing the index markings, the template may also use other features on the syringe as a baseline for measuring dosage, such as the finger grips on the syringe barrel.
Accordingly, in one aspect, the invention relates to a syringe comprising: an elongated syringe barrel formed of a transparent material; a cannula adjacent one end of said barrel for transmission of fluid into our out of said barrel; a plunger disposed in said barrel and extending through an opposite end of said barrel from said one end; index markings along one side of said barrel for use in identifying various dosage amounts; a contrast stripe along another side of the barrel opposite said one side, said contrast stripe forming a marking area along said index markings; a collar moveable along said barrel facilitating indication of or custom marking of a desired dosage amount on said contrast stripe.
In another aspect, the invention relates to a syringe comprising: an elongated syringe barrel formed of a transparent material; a cannula adjacent one end of said barrel for transmission of fluid into our out of said barrel; a plunger disposed in said barrel and extending through an opposite end of said barrel from said one end; index markings along one side of said barrel for use in identifying various dosage amounts; and a dosage collar moveable along said barrel facilitating indication of or custom marking of a desired dosage amount on said barrel.
Referring to the drawings particularly to
As the above discussion indicates, the index markings 18 particularly on small diameter syringes e.g. 1 ml., 0.5 ml. or 0.3 ml. are very difficult to see and it is therefore difficult align the plunger 16 accurately to ensure accurate filling with medicament and therefore correct dose delivery to the patient.
Referring to
In use, the collar 22 is slipped over the end of the syringe (or may be prepositioned at, for example, the finger hold end of the syringe during manufacture) and one or the other of opposite edges of the collar is aligned with the index marking identifying a desired dose. With that alignment, a marking pencil (or other device capable of making a linear mark on the barrel) may be drawn about the barrel, for example, in the area of the contrasting stripe 20 such that the mark can be readily seen even by individuals with impaired eyesight. A numerical reference can also, if desired, be applied to the barrel to identify the line. Because of the necessarily small preprinted index markings, the custom numerical mark can easily be 2 to 3 times larger, or more, allowing comparatively much easier visualization. With the syringe barrel thus custom marked, the plunger bung 50 (see
Referring to
Referring to
In
Referring now to
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the disclosure.
Priority is hereby claimed from U.S. Provisional Application Ser. No. 60/715,590, filed Sep. 12, 2005, the entirety of which is hereby incorporated by reference.
Number | Date | Country | |
---|---|---|---|
60715590 | Sep 2005 | US |