An antihemorrhagic (antihæmorrhagic) agent is a substance that promotes
hemostasis
In biology, hemostasis or haemostasis is a process to prevent and stop bleeding, meaning to keep blood within a damaged blood vessel (the opposite of hemostasis is hemorrhage). It is the first stage of wound healing. This involves coagulation, whi ...
(stops
bleeding
Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...
). It may also be known as a hemostatic (also spelled haemostatic) agent.
Antihemorrhagic agents used in medicine have various mechanisms of action:
* Systemic drugs work by inhibiting
fibrinolysis
Fibrinolysis is a process that prevents blood clots from growing and becoming problematic. Primary fibrinolysis is a normal body process, while secondary fibrinolysis is the breakdown of clots due to a medicine, a medical disorder, or some other c ...
or promoting
coagulation
Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The mechanism o ...
.
* Locally acting hemostatic agents work by causing
vasoconstriction
Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vessel ...
or promoting
platelet aggregation
Platelets, also called thrombocytes (from Greek θρόμβος, "clot" and κύτος, "cell"), are a component of blood whose function (along with the coagulation factors) is to react to bleeding from blood vessel injury by clumping, thereby ini ...
.
Medical uses
Hemostatic agents are used during surgical procedures to achieve hemostasis and are categorized as hemostats, sealants and adhesives. They vary based on their mechanism of action, composition, ease of application, adherence to tissue, immunogenicity and cost. These agents permit rapid hemostasis, better visualization of the surgical area, shorter operative times, decreased requirement for transfusions, decreased wound healing time and overall improvement in patient recovery time.
Types
Systemic
There are several classes of antihemorrhagic drugs used in medicine. These include
antifibrinolytics Antifibrinolytics are a class of medication that are inhibitors of fibrinolysis. Examples include aminocaproic acid (ε-aminocaproic acid) and tranexamic acid. These lysine
Lysine (symbol Lys or K) is an α-amino acid that is a precursor to ma ...
, blood
coagulation factor
Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The mechanism o ...
s,
fibrinogen
Fibrinogen (factor I) is a glycoprotein complex, produced in the liver, that circulates in the blood of all vertebrates. During tissue and vascular injury, it is converted enzymatically by thrombin to fibrin and then to a fibrin-based blood clo ...
, and
vitamin K
Vitamin K refers to structurally similar, fat-soluble vitamers found in foods and marketed as dietary supplements. The human body requires vitamin K for post-synthesis modification of certain proteins that are required for blood coagulation ...
.
Local
Topical hemostatic agents have been gaining popularity for use in
emergency bleeding control
Emergency bleeding control describes actions that control bleeding from a patient who has suffered a traumatic injury or who has a medical condition that has caused bleeding. Many bleeding control techniques are taught as part of first aid throug ...
, especially in
military medicine
The term military medicine has a number of potential connotations. It may mean:
*A medical specialty, specifically a branch of occupational medicine attending to the medical risks and needs (both preventive and interventional) of sold ...
. They are available in three forms—as a granular powder poured on wounds, as a "styptic pencil" or embedded in a
dressing.
Organic
= Microfibrillar collagen
=
Microfibrillar
collagen
Collagen () is the main structural protein in the extracellular matrix found in the body's various connective tissues. As the main component of connective tissue, it is the most abundant protein in mammals, making up from 25% to 35% of the whole ...
hemostat (MCH) is a topical agent composed of resorbable microfibrillar collagen. It attracts platelets and allows for the formation of a blood clot when it comes into contact with blood. Unlike the hemostatic clamp, no mechanical action is involved. The surgeon presses the MCH against a bleeding site, and the collagen attracts and helps with the clotting process to eventually stop bleeding.
The practical application for MCH is different from that of the hemostatic clamp.
= Chitosan
=
Chitosan
Chitosan is a linear polysaccharide composed of randomly distributed β-(1→4)-linked Glucosamine, D-glucosamine (deacetylated unit) and N-Acetylglucosamine, ''N''-acetyl-D-glucosamine (acetylated unit). It is made by treating the chitin shell ...
hemostats are topical agents composed of chitosan and its salts. Chitosan bonds with platelets and red blood cells to form a gel-like clot which seals a bleeding vessel. Unlike other hemostat technologies its action does not require the normal hemostatic pathway and therefore continues to function even when anticoagulants like heparin are present.
Chitosan is used in some emergency hemostats which are designed to stop traumatic life-threatening bleeding. Their use is well established in many military and trauma units.
Inorganic
= Contact activation
=
Kaolin
Kaolinite ( ) is a clay mineral, with the chemical composition Al2 Si2 O5( OH)4. It is an important industrial mineral. It is a layered silicate mineral, with one tetrahedral sheet of silica () linked through oxygen atoms to one octahedral ...
(and the
zeolite
Zeolites are microporous, crystalline aluminosilicate materials commonly used as commercial adsorbents and catalysts. They mainly consist of silicon, aluminium, oxygen, and have the general formula ・y where is either a metal ion or H+. These pos ...
in it) activate the coagulation cascade, and have been used as the active component of hemostatic dressings (for example, in
QuikClot
QuikClot is a brand of hemostatic wound dressing, that contains an agent that promotes blood clotting. It is primarily used by militaries and law enforcement to treat hemorrhaging from trauma.
History
Using zeolite as a clotting agent was ...
).
= Styptics
=
![Alaunblocknebenrasiermesser](https://upload.wikimedia.org/wikipedia/commons/b/b1/Alaunblocknebenrasiermesser.JPG)
A styptic (also spelled stiptic) is a specific type of antihemorrhagic agent that works by contracting
tissue to seal injured
blood vessel
The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away ...
s. Styptic pencils contain
astringent
An astringent (sometimes called adstringent) is a chemical that shrinks or constricts body tissues. The word derives from the Latin ''adstringere'', which means "to bind fast". Calamine lotion, witch hazel, and yerba mansa, a Californian plant ...
s.
A common delivery system for this is a styptic or hemostatic pencil (not to be confused with a
caustic pencil
A caustic pencil (or silver nitrate stick) is a device for applying topical medication containing silver nitrate and potassium nitrate, used to chemically cauterize skin, providing hemostasis or permanently destroying unwanted tissue such as a war ...
). This is a short stick of
medication
A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field and re ...
.
Anhydrous
A substance is anhydrous if it contains no water. Many processes in chemistry can be impeded by the presence of water; therefore, it is important that water-free reagents and techniques are used. In practice, however, it is very difficult to achie ...
aluminium sulfate
Aluminium sulfate is a salt with the chemical formula, formula aluminium, Al2sulfate, (SO4)3. It is soluble in water and is mainly used as a Coagulation (water treatment), coagulating agent (promoting particle collision by neutralizing charge) in ...
is the main ingredient and acts as a vasoconstrictor in order to disable blood flow. The stick is applied directly to the bleeding site. The high
ionic strength
The ionic strength of a solution is a measure of the concentration of ions in that solution. Ionic compounds, when dissolved in water, dissociate into ions. The total electrolyte concentration in solution will affect important properties such as ...
promotes
flocculation
Flocculation, in the field of chemistry, is a process by which colloidal particles come out of suspension to sediment under the form of floc or flake, either spontaneously or due to the addition of a clarifying agent. The action differs from pr ...
of the blood, and the astringent chemical causes local vasoconstriction. Before
safety razor
A safety razor is a shaving implement with a protective device positioned between the edge of the blade and the skin. The initial purpose of these protective devices was to reduce the level of skill needed for injury-free shaving, thereby reduc ...
s were invented, a styptic pencil was a standard part of a shaving kit and was used to seal shaving cuts.
Some people continue to use styptic pencils for minor skin wounds from safety or electric razors.
Styptic powder is used in the
veterinary
Veterinary medicine is the branch of medicine that deals with the prevention, management, diagnosis, and treatment of disease, disorder, and injury in animals. Along with this, it deals with animal rearing, husbandry, breeding, research on nutri ...
trade to stop bleeding from nails that are clipped too closely. This powder is generally used on animals, such as
cat
The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...
s,
dog
The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...
s, and
rabbit
Rabbits, also known as bunnies or bunny rabbits, are small mammals in the family Leporidae (which also contains the hares) of the order Lagomorpha (which also contains the pikas). ''Oryctolagus cuniculus'' includes the European rabbit speci ...
s, whose vein is found in the center of the nail.
[
]
See also
*
ATC code B02 – Antihemorrhagics
*
Hemostatic clamp
*
Hemostatic Powder Spray TC-325
Hemostatic Powder Spray TC-325 (Hemospray or TC-325) is an inert, highly absorptive mineral agent which is used for the treatment of gastrointestinal bleeding. Applied during endoscopy to bleeding lesions, TC-325 is derived from bentonite, and is ...
References
{{Major drug groups
Shaving
Transfusion medicine