Bleeding time

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Bleeding time
Specialty Haematology
MeSH D001760
MedlinePlus 003656

Bleeding time is a medical test done to assess the function of a person's platelets. It involves making a patient bleed, then timing how long it takes for them to stop bleeding using a stopwatch or other suitable devices.

Contents

The term template bleeding time is used when the test is performed to standardized parameters.

A newer alternative to the traditional bleeding time test is the platelet function screen performed on the PFA-100 analyzer. [1]

Usage

The template bleeding time test is a method used when other more reliable and less invasive tests for determining coagulation are not available. [2] Historically, it was used whenever physicians needed information about platelet activation. [3]

Process

The test involves cutting the underside of the subject's forearm, in an area where there is no hair or visible veins. The cut is of a standardized width and depth, and is done quickly by a template device. [4]

IVY method

The IVY method is the traditional format for this test. While both the IVY and Duke's method require the use of a sphygmomanometer, or blood pressure cuff, the IVY method is more invasive than the Duke method, utilizing an incision on the ventral side of the forearm, whereas the Duke method involves puncture with a lancet or special needle. In the IVY method, the blood pressure cuff is placed on the upper arm and inflated to 40 mmHg. A lancet or scalpel blade is used to make a shallow incision that is 1 millimeter deep on the underside of the forearm. [5]

A standard-sized incision is made around 10 mm long and 1 mm deep. The time from when the incision is made until all bleeding has stopped is measured and is called the bleeding time. Every 30 seconds, filter paper or a paper towel is used to draw off the blood.

The test is finished when bleeding has stopped. [6]

A prolonged bleeding time may be a result from decreased number of thrombocytes or impaired blood vessels. However, the depth of the puncture or incision may be the source of error.

Normal values fall between 3 – 10 minutes depending on the method used.

A disadvantage of Ivy's method is closure of puncture wound before stoppage of bleeding. [7]

Duke's method

With the Duke's method, the patient is pricked with a special needle or lancet, preferably on the earlobe [8] or fingertip, after having been swabbed with alcohol. The prick is about 3–4 mm deep. The patient then wipes the blood every 30 seconds with a filter paper. The test ceases when bleeding ceases. The usual time is about 2–5 minutes.

This method is not recommended and cannot be standardized because it can cause a large local hematoma. [7]

Interpretation

Bleeding time may be affected by platelet function, certain vascular disorders and von Willebrand Disease—not by other coagulation factors such as haemophilia. Diseases that may cause prolonged bleeding time include thrombocytopenia, disseminated intravascular coagulation (DIC), Bernard-Soulier disease, and Glanzmann's thrombasthenia. [9]

Aspirin and other cyclooxygenase inhibitors can significantly prolong bleeding time. While warfarin and heparin have their major effects on coagulation factors, an increased bleeding time is sometimes seen with use of these medications as well.

People with von Willebrand disease usually experience increased bleeding time, as von Willebrand factor is a platelet adhesion protein, but this is not considered an effective diagnostic test for this condition. [9]

It is also prolonged in hypofibrinogenemia. [10]

In the British comedy film Doctor in the House (1954), Sir Lancelot Spratt, the intimidating chief of surgery played by James Robertson Justice is asking instructional questions of his medical students. He asks a young student, who has been distracted by a pretty nurse, what "the bleeding time" is. The student looks at his watch and answers "Ten past ten, sir."

Related Research Articles

<span class="mw-page-title-main">Bleeding</span> Loss of blood escaping from the circulatory system

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, vagina or anus, or through a puncture in the skin. Hypovolemia is a massive decrease in blood volume, and death by excessive loss of blood is referred to as exsanguination. Typically, a healthy person can endure a loss of 10–15% of the total blood volume without serious medical difficulties. The stopping or controlling of bleeding is called hemostasis and is an important part of both first aid and surgery.

<span class="mw-page-title-main">Platelet</span> Component of blood aiding in coagulation

Platelets or thrombocytes are a blood component whose function is to react to bleeding from blood vessel injury by clumping, thereby initiating a blood clot. Platelets have no cell nucleus; they are fragments of cytoplasm derived from the megakaryocytes of the bone marrow or lung, which then enter the circulation. Platelets are found only in mammals, whereas in other vertebrates, thrombocytes circulate as intact mononuclear cells.

<span class="mw-page-title-main">Coagulation</span> Process of formation of blood clots

Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The process of coagulation involves activation, adhesion and aggregation of platelets, as well as deposition and maturation of fibrin.

<span class="mw-page-title-main">Disseminated intravascular coagulation</span> Medical condition where blood clots block small blood vessels

Disseminated intravascular coagulation (DIC) is a condition in which blood clots form throughout the body, blocking small blood vessels. Symptoms may include chest pain, shortness of breath, leg pain, problems speaking, or problems moving parts of the body. As clotting factors and platelets are used up, bleeding may occur. This may include blood in the urine, blood in the stool, or bleeding into the skin. Complications may include organ failure.

von Willebrand disease Medical condition

Von Willebrand disease (VWD) is the most common hereditary blood-clotting disorder in humans. An acquired form can sometimes result from other medical conditions. It arises from a deficiency in the quality or quantity of von Willebrand factor (VWF), a multimeric protein that is required for platelet adhesion. It is known to affect several breeds of dogs as well as humans. The three forms of VWD are hereditary, acquired, and pseudo or platelet type. The three types of hereditary VWD are VWD type 1, VWD type 2, and VWD type 3. Type 2 contains various subtypes. Platelet type VWD is also an inherited condition.

In biology, hemostasis or haemostasis is a process to prevent and stop bleeding, meaning to keep blood within a damaged blood vessel. It is the first stage of wound healing. Hemostasis involves three major steps:

<span class="mw-page-title-main">Thrombocytopenia</span> Abnormally low levels of platelets in the blood

In hematology, thrombocytopenia is a condition characterized by abnormally low levels of platelets in the blood. Low levels of platelets in turn may lead to prolonged or excessive bleeding. It is the most common coagulation disorder among intensive care patients and is seen in a fifth of medical patients and a third of surgical patients.

Low-molecular-weight heparin (LMWH) is a class of anticoagulant medications. They are used in the prevention of blood clots and, in the treatment of venous thromboembolism, and the treatment of myocardial infarction.

von Willebrand factor Mammalian protein involved in blood clotting

Von Willebrand factor (VWF) is a blood glycoprotein that promotes hemostasis, specifically, platelet adhesion. It is deficient and/or defective in von Willebrand disease and is involved in many other diseases, including thrombotic thrombocytopenic purpura, Heyde's syndrome, and possibly hemolytic–uremic syndrome. Increased plasma levels in many cardiovascular, neoplastic, metabolic, and connective tissue diseases are presumed to arise from adverse changes to the endothelium, and may predict an increased risk of thrombosis.

<span class="mw-page-title-main">Bleeding diathesis</span> High tendency to bleed due to a blood clotting disorder

In medicine (hematology), bleeding diathesis is an unusual susceptibility to bleed (hemorrhage) mostly due to hypocoagulability, in turn caused by a coagulopathy. Therefore, this may result in the reduction of platelets being produced and leads to excessive bleeding. Several types of coagulopathy are distinguished, ranging from mild to lethal. Coagulopathy can be caused by thinning of the skin, such that the skin is weakened and is bruised easily and frequently without any trauma or injury to the body. Also, coagulopathy can be contributed by impaired wound healing or impaired clot formation.

Thromboelastography (TEG) is a method of testing the efficiency of blood coagulation. It is a test mainly used in surgery and anesthesiology, although increasingly used in resuscitations in emergency departments, intensive care units, and labor and delivery suites. More common tests of blood coagulation include prothrombin time (PT) and partial thromboplastin time (aPTT) which measure coagulation factor function, but TEG also can assess platelet function, clot strength, and fibrinolysis which these other tests cannot.

Congenital afibrinogenemia is a rare, genetically inherited blood fibrinogen disorder in which the blood does not clot normally due to the lack of fibrinogen, a blood protein necessary for coagulation. This disorder is autosomal recessive, meaning that two unaffected parents can have a child with the disorder. The lack of fibrinogen expresses itself with excessive and, at times, uncontrollable bleeding.

<span class="mw-page-title-main">Hypoprothrombinemia</span> Medical condition

Hypoprothrombinemia is a rare blood disorder in which a deficiency in immunoreactive prothrombin, produced in the liver, results in an impaired blood clotting reaction, leading to an increased physiological risk for spontaneous bleeding. This condition can be observed in the gastrointestinal system, cranial vault, and superficial integumentary system, affecting both the male and female population. Prothrombin is a critical protein that is involved in the process of hemostasis, as well as illustrating procoagulant activities. This condition is characterized as an autosomal recessive inheritance congenital coagulation disorder affecting 1 per 2,000,000 of the population, worldwide, but is also attributed as acquired.

<span class="mw-page-title-main">Bernard–Soulier syndrome</span> Medical condition

Bernard–Soulier syndrome (BSS) is a rare autosomal recessive bleeding disorder that is caused by a deficiency of the glycoprotein Ib-IX-V complex (GPIb-IX-V), the receptor for von Willebrand factor. The incidence of BSS is estimated to be less than 1 case per million persons, based on cases reported from Europe, North America, and Japan. BSS is a giant platelet disorder, meaning that it is characterized by abnormally large platelets.

<span class="mw-page-title-main">Ristocetin</span> Chemical compound

Ristocetin is a glycopeptide antibiotic, obtained from Amycolatopsis lurida, previously used to treat staphylococcal infections. It is no longer used clinically because it caused thrombocytopenia and platelet agglutination. It is now used solely to assay those functions in vitro in the diagnosis of conditions such as von Willebrand disease (vWD) and Bernard–Soulier syndrome. Platelet agglutination caused by ristocetin can occur only in the presence of von Willebrand factor multimers, so if ristocetin is added to blood lacking the factor, the platelets will not clump.

Venom-induced consumption coagulopathy (VICC) is a medical condition caused by the effects of some snake and caterpillar venoms on the blood. Important coagulation factors are activated by the specific serine proteases in the venom and as they become exhausted, coagulopathy develops. Symptoms are consistent with uncontrolled bleeding. Diagnosis is made using blood tests that assess clotting ability along with recent history of envenomation. Treatment generally involves pressure dressing, confirmatory blood testing, and antivenom administration.

<span class="mw-page-title-main">Quebec platelet disorder</span> Medical condition

Quebec platelet disorder (QPD) is a rare autosomal dominant bleeding disorder first described in a family from the province of Quebec, Canada. The disorder is characterized by large amounts of the fibrinolytic enzyme urokinase-type plasminogen activator (uPA) in platelets. This causes accelerated fibrinolysis which can result in bleeding.

Clotting time is a general term for the time required for a sample of blood to form a clot, or, in medical terms, coagulate. The term "clotting time" is often used when referring to tests such as the prothrombin time (PT), activated partial thromboplastin time, activated clotting time (ACT), thrombin time (TT), or Reptilase time. These tests are coagulation studies performed to assess the natural clotting ability of a sample of blood. In a clinical setting, healthcare providers will order one of these tests to evaluate a patient's blood for any abnormalities in the time it takes for their blood to clot. Each test involves adding a specific substance to the blood and measuring the time until the blood forms fibrin which is one of the first signs of clotted blood. Each test points to a different component of the clotting sequence which is made up of coagulation factors that help form clots. Abnormal results could be due to a number of reasons including, but, not limited to, deficiency in clotting factors, dysfunction of clotting factors, blood-thinning medications, medication side-effects, platelet deficiency, inherited bleeding or clotting disorders, liver disease, or advanced illness resulting in a medical emergency known as disseminated intravascular coagulation (DIC).

The fibrinolysis system is responsible for removing blood clots. Hyperfibrinolysis describes a situation with markedly enhanced fibrinolytic activity, resulting in increased, sometimes catastrophic bleeding. Hyperfibrinolysis can be caused by acquired or congenital reasons. Among the congenital conditions for hyperfibrinolysis, deficiency of alpha-2-antiplasmin or plasminogen activator inhibitor type 1 (PAI-1) are very rare. The affected individuals show a hemophilia-like bleeding phenotype. Acquired hyperfibrinolysis is found in liver disease, in patients with severe trauma, during major surgical procedures, and other conditions. A special situation with temporarily enhanced fibrinolysis is thrombolytic therapy with drugs which activate plasminogen, e.g. for use in acute ischemic events or in patients with stroke. In patients with severe trauma, hyperfibrinolysis is associated with poor outcome. Moreover, hyperfibrinolysis may be associated with blood brain barrier impairment, a plasmin-dependent effect due to an increased generation of bradykinin.

Thromboelastometry (TEM), previously named rotational thromboelastography (ROTEG) or rotational thromboelastometry (ROTEM), is an established viscoelastic method for hemostasis testing in whole blood. It is a modification of traditional thromboelastography (TEG).

References

  1. ↑ Alhaj, Dana; Hagedorn, Nikola; Cuntz, Franziska; Reschke, Madlen; Schuldes, Joerg; Ruthenberg, Juliane; Bakchoul, Tamam; Greinacher, Andreas; Holzhauer, Susanne (2024). "ISTH bleeding assessment tool and platelet function analyzer in children with mild inherited platelet function disorders". European Journal of Haematology. 113 (1): 54–65. doi: 10.1111/ejh.14198 . ISSN   0902-4441. PMID   38549165.
  2. ↑ American Society for Clinical Pathology, "Five Things Doctors and Patients Should Question", Choosing Wisely: an initiative of the ABIM Foundation , American Society for Clinical Pathology, retrieved August 1, 2013, which cites
  3. ↑ Peterson, P.; Hayes, T. E.; Arkin, C. F.; Bovill, E. G.; Fairweather, R. B.; Rock Jr, W. A.; Triplett, D. A.; Brandt, J. T. (1998). "The preoperative bleeding time test lacks clinical benefit: College of American Pathologists' and American Society of Clinical Pathologists' position article". Archives of Surgery. 133 (2): 134–139. doi:10.1001/archsurg.133.2.134. PMID   9484723.
  4. ↑ Quiroga, T.; Goycoolea, M.; Muñoz, B.; Morales, M.; Aranda, E.; Panes, O.; Pereira, J.; Mezzano, D. (2004). "Template bleeding time and PFA-100® have low sensitivity to screen patients with hereditary mucocutaneous hemorrhages: comparative study in 148 patients". Journal of Thrombosis and Haemostasis. 2 (6): 892–898. doi:10.1111/j.1538-7836.2004.00693.x. PMID   15140124.
  5. ↑ Burns, E. R.; Lawrence, C. (1989). "Bleeding time. A guide to its diagnostic and clinical utility". Archives of Pathology & Laboratory Medicine. 113 (11): 1219–1224. ISSN   0003-9985. PMID   2535679.
  6. ↑ "Blood Chemistries". Archived from the original on August 14, 2007. Retrieved 2009-01-02.
  7. 1 2 Dg, Dayyal (2016). "BLEEDING TIME (BT) AND CLOTTING TIME (CT)". BioScience. ISSN   2521-5760.
  8. ↑ Schafer, Andrew I.; Loscalzo, Joseph (2003). Thrombosis and hemorrhage. Hagerstwon, MD: Lippincott Williams & Wilkins. p. 397. ISBN   978-0-7817-3066-2.
  9. 1 2 Mehic, Dino; Assinger, Alice; Gebhart, Johanna (2024-07-01). "Utility of Global Hemostatic Assays in Patients with Bleeding Disorders of Unknown Cause". Hämostaseologie (in German). doi:10.1055/a-2330-9112. ISSN   0720-9355. PMID   38950624.
  10. ↑ "Bleeding Time". Archived from the original on September 14, 2006. Retrieved 2009-01-02.
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