Molecular sieve abstract
A composition for clotting blood comprises a molecular sieve material.
The molecular sieve material is in the form of particles, the particles
having an average diameter of about 0.2 millimeters (mm) to about
10 mm. The molecular sieve material may be a zeolite, the zeolite
being an aluminosilicate comprising at least one of calcium and
sodium.
Molecular sieve claims
1. A composition for clotting blood, said composition comprising:
a molecular sieve material, said molecular sieve material being
in the form of particles, said particles having an average diameter
of about 0.2 mm to about 10 mm.
2. The composition of claim 1 wherein said molecular sieve material
is a zeolite.
3. The composition of claim 2 wherein said zeolite is an aluminosilicate
further comprising at least one of calcium and sodium.
4. The composition of claim 2 wherein said zeolite is an A-type
crystal.
5. The composition of claim 1 further comprising an antibiotic,
an antifungal agent, an antimicrobial agent, an anti-inflammatory
agent, an analgesic, a compound containing silver ions, or a combination
of any of the foregoing materials.
6. The composition of claim 1 further comprising a botanical agent.
7. The composition of claim 1 wherein a moisture content is up
to about 20% by weight.
8. The composition of claim 1 wherein a moisture content is about
4% by weight to about 15% by weight.
9. The composition of claim 1 wherein a moisture content is about
5% by weight to about 12% by weight.
10. A composition for clotting blood, said composition comprising:
a molecular sieve material, said molecular sieve material being
in the form of particles, said particles having an average diameter
of about 1 mm to about 7 mm.
11. The composition of claim 10 wherein said molecular sieve material
is a zeolite.
12. The composition of claim 11 wherein said zeolite is an aluminosilicate
further comprising at least one of calcium and sodium.
13. The composition of claim 11 wherein said zeolite is an A-type
crystal.
14. The composition of claim 10 further comprising an antibiotic,
an antifungal agent, an antimicrobial agent, an anti-inflammatory
agent, an analgesic, a compound containing silver ions, or a combination
of any of the foregoing materials.
15. The composition of claim 10 further comprising a botanical
agent.
16. The composition of claim 10 wherein a moisture content is
up to about 20% by weight.
17. The composition of claim 10 wherein a moisture content is
about 4% by weight to about 15% by weight.
18. The composition of claim 10 wherein a moisture content is
about 5% by weight to about 12% by weight.
19. A composition for clotting blood, said composition comprising:
a molecular sieve material, said molecular sieve material being
in the form of particles, said particles having an average diameter
of about 2 mm to about 5 mm.
20. The composition of claim 19 wherein said molecular sieve material
is a zeolite.
21. The composition of claim 20 wherein said zeolite is an aluminosilicate
further comprising at least one of calcium and sodium.
22. The composition of claim 20 wherein said zeolite is an A-type
crystal.
23. The composition of claim 19 further comprising an antibiotic,
an antifungal agent, an antimicrobial agent, an anti-inflammatory
agent, an analgesic, a compound containing silver ions, or a combination
of any of the foregoing materials.
24. The composition of claim 19 further comprising a botanical
agent.
25. The composition of claim 19 wherein a moisture content is
up to about 20% by weight.
26. The composition of claim 19 wherein a moisture content is
about 4% by weight to about 15% by weight.
27. The composition of claim 19 wherein a moisture content is
about 5% by weight to about 12% by weight.
Molecular sieve description
TECHNICAL FIELD
[0001] The present invention relates generally to blood clotting
devices and, more particularly, to blood clotting materials and
compositions for use as bleeding control devices.
BACKGROUND OF THE INVENTION
[0002] Blood is a liquid tissue that includes red cells, white
cells, corpuscles, and platelets dispersed in a liquid phase. The
liquid phase is plasma, which includes acids, lipids, solublized
electrolytes, and proteins. The proteins are suspended in the liquid
phase and can be separated out of the liquid phase by any of a variety
of methods such as filtration, centrifugation, electrophoresis,
and immunochemical techniques. One particular protein suspended
in the liquid phase is fibrinogen. When bleeding occurs, the fibrinogen
reacts with water and thrombin (an enzyme) to form fibrin, which
is insoluble in blood and polymerizes to form clots.
[0003] In a wide variety of circumstances, animals, including humans,
can be wounded. Often bleeding is associated with such wounds. In
some circumstances, the wound and the bleeding are minor, and normal
blood clotting functions in addition to the application of simple
first aid are all that is required. Unfortunately, however, in other
circumstances substantial bleeding can occur. These situations usually
require specialized equipment and materials as well as personnel
trained to administer appropriate aid. If such aid is not readily
available, excessive blood loss can occur. When bleeding is severe,
sometimes the immediate availability of equipment and trained personnel
is still insufficient to stanch the flow of blood in a timely manner.
[0004] Moreover, severe wounds can often be inflicted in remote
areas or in situations, such as on a battlefield, where adequate
medical assistance is not immediately available. In these instances,
it is important to stop bleeding, even in less severe wounds, long
enough to allow the injured person or animal to receive medical
attention.
[0005] In an effort to address the above-described problems, materials
have been developed for controlling excessive bleeding in situations
where conventional aid is unavailable or less than optimally effective.
Although these materials have been shown to be somewhat successful,
they are not effective enough for traumatic wounds and tend to be
expensive. Furthermore, these materials are sometimes ineffective
in all situations and can be difficult to apply as well as remove
from a wound.
[0006] Additionally, or alternatively, the previously developed
materials can produce undesirable side effects, particularly in
instances in which they are misapplied to wounds or in which they
are applied by untrained personnel. For example, because prior art
blood clotting material is generally a powder or in fine particulate
form, the surface area of the material is relatively large. The
typical moisture content of a large surface area blood clotting
material is generally up to about 15% of the total weight of the
material. This combination of surface area and moisture content
often produces an exothermic reaction upon the application of the
material to blood. Depending upon the specific surface area and
the specific amount of moisture, the resulting exothermia may be
sufficient to cause discomfort to or even burn the patient. Although
some prior art patents specifically recite the resulting exothermia
as being a desirable feature that can provide cauterization of the
wound, there exists the possibility that the tissue at and around
the wound site can be undesirably damaged.
[0007] Based on the foregoing, it is a general object of the present
invention to provide a bleeding control material that overcomes
or improves upon the prior art.
SUMMARY OF THE INVENTION
[0008] According to one aspect of the present invention, a composition
for clotting blood comprises a molecular sieve material in particle
form, the particles having an average diameter of about 0.2 mm to
about 10 mm. The molecular sieve material may be a zeolite such
as crystalline aluminosilicate having calcium and/or sodium components.
Because the molecular sieve material is hydrophilic in nature, the
crystalline structure adsorbs water into the interstices of the
structure when left exposed in an environment having any degree
of humidity.
[0009] Surprisingly, one advantage that has been discovered is
that the molecular sieve material reacts less exothermically with
blood as the particle size is increased. As the particle size increases,
the surface area of the particles that the blood can come into contact
with decreases. However, the porous nature of the material still
allows water to be wicked away to cause thickening of the blood,
thereby facilitating the formation of clots. Because the particle
surface area exposed to the blood is reduced, a less aggressive
drawing of moisture from the blood is realized, which tempers the
exothermic effects experienced at the wound site.
[0010] Still another advantage of the present invention is that
it is easily applied to an open wound. Particularly when the composition
is in particlized form, it can be readily removed from sterilized
packaging and deposited directly at the points from which blood
emanates to dress the wound. Depositing the composition typically
comprises pouring the particles directly on the wound.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0011] Disclosed herein are compositions directed to the clotting
of blood and the dressing of wounds. The compositions generally
comprise molecular sieve materials that can minimize or stop a flow
of blood by absorbing at least portions of the liquid phases of
the blood, thereby promoting clotting.
[0012] In one embodiment of the present invention, the molecular
sieve material comprises a zeolite. As used herein, the term "zeolite"
refers to a crystalline form of aluminosilicate having the ability
to be dehydrated without experiencing significant changes in the
crystalline structure. The zeolite may include one or more ionic
species such as, for example, calcium and sodium moieties. Typically,
the zeolite is a friable material that is about 90% by weight calcium
and about 10% by weight sodium. The calcium portion contains crystals
that are about 5 angstroms in size, and the sodium portion contains
crystals that are about 4 angstroms in size. The preferred molecular
structure of the zeolite is an "A-type" crystal, namely,
one having a cubic crystalline structure that defines round or substantially
round openings.
[0013] The zeolites may be mixed with or otherwise used in conjunction
with other materials having the ability to by dehydrated without
significant changes in crystalline structure. Such materials include,
but are not limited to, magnesium sulfate, sodium metaphosphate,
calcium chloride, dextrin, combinations of the foregoing materials,
and hydrates of the foregoing materials.
[0014] Zeolites for use in the disclosed applications may be naturally
occurring or synthetically produced. Numerous varieties of naturally
occurring zeolites are found as deposits in sedimentary environments
as well as in other places. Naturally occurring zeolites that may
be applicable to the compositions described herein include, but
are not limited to, analcite, chabazite, heulandite, natrolite,
stilbite, and thomosonite. Synthetically produced zeolites that
may also find use in the compositions and methods described herein
are generally produced by processes in which rare earth oxides are
substituted by silicates, alumina, or alumina in combination with
alkali or alkaline earth metal oxides.
[0015] The zeolite particles may be substantially spherical or
irregular (e.g., balls, beads, pellets, or the like) or in the forms
of chips or flakes. Substantially spherical or irregular particles,
as well as chips or flakes, are about 0.2 millimeters (mm) to about
10 mm in diameter, preferably about 1 mm to about 7 mm in diameter,
and more preferably about 2 mm to about 5 mm in diameter.
[0016] Alternately, the particles may be rod-shaped and configured
to have round, irregular, or angular cross sections. In any configuration,
the rods are typically produced via an extrusion process. Particles
that are rod-shaped are about 0.2 mm to about 10 mm in length, preferably
about 1 mm to about 7 mm in length, and more preferably about 2
mm to about 5 mm in length.
[0017] In any embodiment (balls, beads, pellets, flakes, chips,
rods), less particle surface area is available to be contacted by
blood as the particle size is increased. Therefore, the rate of
clotting can be controlled by varying the particle size. Surprisingly,
it has been found that by maintaining particle size within the ranges
provided above, such that the material comprises discrete elements,
a correlative relationship between the surface area and exothermic
effects when applied to blood. Furthermore, the accumulation of
moisture (which also has an effect on the exothermic effects of
the zeolite) can also be controlled.
[0018] Under super-humid conditions, zeolite material can be made
to have a moisture content of about 21% by weight. Preferably, the
moisture content of the zeolite as utilized in the present invention
is about 4% by weight to about 15% by weight, and more preferably
about 5% by weight to about 12% by weight. In the preparation of
zeolite material for the blood clotting composition of the present
invention (i.e., formation of the material into particle form),
an initial level of hydration of the zeolite may be controlled by
the application of heat to the zeolite material either before or
after the material is formed into particles. However, it has also
surprisingly been found that as the particle size of the zeolite
is increased, the moisture content has less of a correlative effect
on any exothermia produced as the result of mixing the particlized
zeolite in blood. Accordingly, at almost all ambient conditions
the amount of moisture of the zeolite material is between about
4% by weight and about 10% by weight and moisture at this level
has little effect on the efficacy of the zeolite as a blood clotting
composition.
[0019] Various materials may be mixed with, associated with, or
incorporated into the zeolites to maintain an antiseptic environment
at the wound site or to provide functions that are supplemental
to the clotting functions of the zeolites. Exemplary materials that
can be used include, but are not limited to, pharmaceutically-active
compositions such as antibiotics, antifungal agents, antimicrobial
agents, anti-inflammatory agents, analgesics (e.g., cimetidine,
chloropheniramine maleate, diphenhydramine hydrochloride, and promethazine
hydrochloride), compounds containing silver ions, and the like.
Other materials that can be incorporated to provide additional hemostatic
functions include ascorbic acid, tranexamic acid, rutin, and thrombin.
Botanical agents having desirable effects on the wound site may
also be added.
[0020] Although this invention has been shown and described with
respect to the detailed embodiments thereof, it will be understood
by those of skill in the art that various changes may be made and
equivalents may be substituted for elements thereof without departing
from the scope of the invention. In addition, modifications may
be made to adapt a particular situation or material to the teachings
of the invention without departing from the essential scope thereof.
Therefore, it is intended that the invention not be limited to the
particular embodiments disclosed in the above detailed description,
but that the invention will include all embodiments falling within
the scope of the appended claims.
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