Fingerstick

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Blood glucose monitoring

In medicine, some blood tests are conducted on capillary blood obtained by fingerstick (or fingerprick) (or, for neonates, by an analogous heelprick). The site, free of surface arterial flow, where the blood is to be collected is sterilized with a topical germicide, and the skin pierced with a sterile lancet. [1] After a droplet has formed, capillary blood is captured in a capillary tube (usually relying on surface tension). Blood cells drawn from fingersticks have a tendency to undergo hemolysis, especially if the finger is "milked" to obtain more blood. [2]

Contents

Uses

Tests commonly conducted on the capillary blood collected are:

Fingersticks are routine for hardy[ citation needed ] adults, but are generally performed on children and the elderly only if a small amount of blood suffices for needed tests. Neonates are given heelpricks instead, as this is less likely to cause permanent damage.[ citation needed ]

Related Research Articles

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Hemoglobin is a protein containing iron that facilitates the transport of oxygen in red blood cells. Almost all vertebrates contain hemoglobin, with the exception of the fish family Channichthyidae. Hemoglobin in the blood carries oxygen from the respiratory organs to the other tissues of the body, where it releases the oxygen to enable aerobic respiration which powers the animal's metabolism. A healthy human has 12 to 20 grams of hemoglobin in every 100 mL of blood. Hemoglobin is a metalloprotein, a chromoprotein, and globulin.

<span class="mw-page-title-main">Blood glucose monitoring</span> Use of a glucose monitor for testing the concentration of glucose in the blood

Blood glucose monitoring is the use of a glucose meter for testing the concentration of glucose in the blood (glycemia). Particularly important in diabetes management, a blood glucose test is typically performed by piercing the skin to draw blood, then applying the blood to a chemically active disposable 'test-strip'. The other main option is continuous glucose monitoring (CGM). Different manufacturers use different technology, but most systems measure an electrical characteristic and use this to determine the glucose level in the blood. Skin-prick methods measure capillary blood glucose, whereas CGM correlates interstitial fluid glucose level to blood glucose level. Measurements may occur after fasting or at random nonfasting intervals, each of which informs diagnosis or monitoring in different ways.

<span class="mw-page-title-main">Red blood cell</span> Oxygen-delivering blood cell and the most common type of blood cell

Red blood cells (RBCs), scientific name erythrocytes (from Greek erythros 'red' and kytos 'hollow vessel', with -cyte translated as 'cell' in modern usage), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells) or haematids, are the most common type of blood cell and the vertebrate's principal means of delivering oxygen (O2) to the body tissues—via blood flow through the circulatory system. Erythrocytes take up oxygen in the lungs, or in fish the gills, and release it into tissues while squeezing through the body's capillaries.

Liver function tests, also referred to as a hepatic panel, are groups of blood tests that provide information about the state of a patient's liver. These tests include prothrombin time (PT/INR), activated partial thromboplastin time (aPTT), albumin, bilirubin, and others. The liver transaminases aspartate transaminase and alanine transaminase are useful biomarkers of liver injury in a patient with some degree of intact liver function.

<span class="mw-page-title-main">Venipuncture</span> Process of obtaining intravenous access

In medicine, venipuncture or venepuncture is the process of obtaining intravenous access for the purpose of venous blood sampling or intravenous therapy. In healthcare, this procedure is performed by medical laboratory scientists, medical practitioners, some EMTs, paramedics, phlebotomists, dialysis technicians, and other nursing staff. In veterinary medicine, the procedure is performed by veterinarians and veterinary technicians.

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

Kernicterus is a bilirubin-induced brain dysfunction. The term was coined in 1904 by Christian Georg Schmorl. Bilirubin is a naturally occurring substance in the body of humans and many other animals, but it is neurotoxic when its concentration in the blood is too high, a condition known as hyperbilirubinemia. Hyperbilirubinemia may cause bilirubin to accumulate in the grey matter of the central nervous system, potentially causing irreversible neurological damage. Depending on the level of exposure, the effects range from clinically unnoticeable to severe brain damage and even death.

<span class="mw-page-title-main">Arterial blood gas test</span> A test of blood taken from an artery that measures the amounts of certain dissolved gases

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<span class="mw-page-title-main">Blood test</span> Laboratory analysis performed on a blood sample

A blood test is a laboratory analysis performed on a blood sample that is usually extracted from a vein in the arm using a hypodermic needle, or via fingerprick. Multiple tests for specific blood components, such as a glucose test or a cholesterol test, are often grouped together into one test panel called a blood panel or blood work. Blood tests are often used in health care to determine physiological and biochemical states, such as disease, mineral content, pharmaceutical drug effectiveness, and organ function. Typical clinical blood panels include a basic metabolic panel or a complete blood count. Blood tests are also used in drug tests to detect drug abuse.

<span class="mw-page-title-main">Hematocrit</span> Volume percentage of red blood cells in blood

The hematocrit, also known by several other names, is the volume percentage (vol%) of red blood cells (RBCs) in blood, measured as part of a blood test. The measurement depends on the number and size of red blood cells. It is normally 40.7–50.3% for males and 36.1–44.3% for females. It is a part of a person's complete blood count results, along with hemoglobin concentration, white blood cell count and platelet count.

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

Hereditary spherocytosis (HS) is a congenital hemolytic disorder, wherein a genetic mutation coding for a structural membrane protein phenotype leads to a spherical shaping of erythrocytic cellular morphology. As erythrocytes are sphere-shaped (spherocytosis), rather than the normal biconcave disk-shaped, their morphology interferes with these cells' abilities to be flexible during circulation throughout the entirety of the body – arteries, arterioles, capillaries, venules, veins, and organs. This difference in shape also makes the red blood cells more prone to rupture under osmotic stress, mechanical stress, or both. Cells with these dysfunctional proteins are degraded in the spleen, which leads to a shortage of erythrocytes resulting in hemolytic anemia.

<span class="mw-page-title-main">Polycythemia</span> Laboratory diagnosis of high hemoglobin content in blood

Polycythemia is a laboratory finding in which the hematocrit and/or hemoglobin concentration are increased in the blood. Polycythemia is sometimes called erythrocytosis, and there is significant overlap in the two findings, but the terms are not the same: polycythemia describes any increase in hematocrit and/or hemoglobin, while erythrocytosis describes an increase specifically in the number of red blood cells in the blood.

<span class="mw-page-title-main">Prothrombin time</span> Assay for evaluating the extrinsic pathway & common pathway of coagulation

The prothrombin time (PT) – along with its derived measures of prothrombin ratio (PR) and international normalized ratio (INR) – is an assay for evaluating the extrinsic pathway and common pathway of coagulation. This blood test is also called protime INR and PT/INR. They are used to determine the clotting tendency of blood, in such things as the measure of warfarin dosage, liver damage, and vitamin K status. PT measures the following coagulation factors: I (fibrinogen), II (prothrombin), V (proaccelerin), VII (proconvertin), and X.

<span class="mw-page-title-main">Blood lancet</span> Small medical instrument used for blood sampling

A blood lancet, or simply lancet, is a small medical implement used for capillary blood sampling. A blood lancet, sometimes called a lance, is similar to a scalpel style lancet, but with a double-edged blade and a pointed end. It can even be a specialized type of sharp needle. Lancets are used to make punctures, such as a fingerstick, to obtain small blood specimens. Blood lancets are generally disposable.

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

Neonatal jaundice is a yellowish discoloration of the white part of the eyes and skin in a newborn baby due to high bilirubin levels. Other symptoms may include excess sleepiness or poor feeding. Complications may include seizures, cerebral palsy, or kernicterus.

<span class="mw-page-title-main">Kleihauer–Betke test</span> Blood test used to measure the amount of fetal hemoglobin

The Kleihauer–Betke ("KB") test, Kleihauer–Betke ("KB") stain, Kleihauer test or acid elution test is a blood test used to measure the amount of fetal hemoglobin transferred from a fetus to a mother's bloodstream. It is usually performed on Rh-negative mothers to determine the required dose of Rho(D) immune globulin (RhIg) to inhibit formation of Rh antibodies in the mother and prevent Rh disease in future Rh-positive children. It is named after Enno Kleihauer and Klaus Betke who described it in 1957.

<span class="mw-page-title-main">Sickle cell trait</span> Medical condition

Sickle cell trait describes a condition in which a person has one abnormal allele of the hemoglobin beta gene, but does not display the severe symptoms of sickle cell disease that occur in a person who has two copies of that allele. Those who are heterozygous for the sickle cell allele produce both normal and abnormal hemoglobin.

In ABO hemolytic disease of the newborn maternal IgG antibodies with specificity for the ABO blood group system pass through the placenta to the fetal circulation where they can cause hemolysis of fetal red blood cells which can lead to fetal anemia and HDN. In contrast to Rh disease, about half of the cases of ABO HDN occur in a firstborn baby and ABO HDN does not become more severe after further pregnancies.

Anemia of prematurity (AOP) refers to a form of anemia affecting preterm infants with decreased hematocrit. AOP is a normochromic, normocytic hypoproliferative anemia. The primary mechanism of AOP is a decrease in erythropoietin (EPO), a red blood cell growth factor.

<span class="mw-page-title-main">Packed red blood cells</span> Red blood cells separated for blood transfusion

Packed red blood cells, also known as packed cells, are red blood cells that have been separated for blood transfusion. The packed cells are typically used in anemia that is either causing symptoms or when the hemoglobin is less than usually 70–80 g/L. In adults, one unit brings up hemoglobin levels by about 10 g/L. Repeated transfusions may be required in people receiving cancer chemotherapy or who have hemoglobin disorders. Cross-matching is typically required before the blood is given. It is given by injection into a vein.

A random glucose test, also known as a random blood glucose test or a casual blood glucose test is a glucose test on the blood of a non-fasting person. This test assumes a recent meal and therefore has higher reference values than the fasting blood glucose (FBG) test.

References

  1. Centers for Disease Control, Capillary blood sampling protocol (PDF)
  2. Carreyrou, John (21 May 2018). "A New Look Inside Theranos' Dysfunctional Corporate Culture". Wired. Retrieved 23 May 2018.
  3. Ansell, J.; Holden, A.; Knapic, N. (November 1989). "Patient Self-Management of Oral Anticoagulation Guided by Capillary (Fingerstick) Whole Blood Prothrombin Time". Arch Intern Med. 149 (11): 2509–11. doi:10.1001/archinte.1989.00390110085018. PMID   2818110.