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Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


Farlex Partner Medical Dictionary © Farlex 2012


1. Thin-layer chromatography, see there.
2. Total lung capacity, see there.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


Abbreviation for thin-layer chromatography; total lung capacity.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


(ka-pas'i-te) [Fr. fr L. capacitas, capacity]
1. The potential ability to contain; the potential power to do something.
2. Cubic content.
3. The ability to perform mentally.
4. The measure of the electrical output of a generator.

forced vital capacity

Abbreviation: FVC
The volume of gas exhaled from the completely inflated lungs during a maximal expiratory effort.

Patient care

Patients with a significantly reduced vital capacity are prone to respiratory failure, esp. during the immediate postoperative period.

functional bladder capacity

See: functional capacity (2)

functional capacity

1. In cardiovascular medicine, the ability of a person to perform aerobic work during maximum oxygen intake.
2. The largest amount of urine a patient can comfortably hold before feeling the urge to urinate. It may be estimated by recording how much urine a patient voids on each occasion during a two- or three-day period. The largest volume is the called the functional bladder capacity.

maximum aerobic capacity

Abbreviation: VO2 max BP
The maximum amount of physiological work that an individual can do, as measured by oxygen consumption. VO2 max is determined by the combination of aging and cardiovascular conditioning and is associated with the efficiency of oxygen extraction in the tissues.
Synonym: maximal oxygen uptake

mental capacity

The ability of a person to make legally valid decisions.

Patient care

This ability can be tested with assessment tools such as the Aid to Capacity Evaluation (ACE) test, available on the Internet at

testamentary capacity

The ability of a person to make a will or living will.

timed vital capacity

A test of vital capacity of the lungs expressed with respect to the volume of air that can be quickly and forcibly breathed out in a certain amount of time.
See: FEV1

total lung capacity

Abbreviation: TLC
The volume of air in the lungs after a maximal inspiration. This amount is important in evaluating the ability of the lung to exchange oxygen and carbon dioxide. See: pulmonary function test ; vital capacity ; volume, residual

vital capacity

The volume of air that can be exhaled from the lungs after a maximal inspiration. This amount is important in evaluating the ability of the lung to exchange oxygen and carbon dioxide.
See: pulmonary function test ; total lung capacity ; volume, residual

total lung capacity

Abbreviation: TLC
The volume of air in the lungs after a maximal inspiration. This amount is important in evaluating the ability of the lung to exchange oxygen and carbon dioxide. See: pulmonary function test ; vital capacity ; volume, residual
See also: capacity


(kath'et-er) [Gr. katheter, a tube for insertion]
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TYPES OF CATHETERS: Single-lumen catheter
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TYPES OF CATHETERS: Double-lumen catheter
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TYPES OF CATHETERS: Triple-lumen catheter
A tube passed into the body for evacuating or injecting fluids. It may be made of elastic, elastic web, rubber, glass, metal, or plastic. See: illustration

antimicrobial-impregnated central catheter

An intravenous catheter saturated with antibiotics, designed to decrease the likelihood of colonization or infection of indwelling infusion lines.

arterial catheter

A catheter inserted into an artery to measure pressure, remove blood, inject medication or radiographic contrast media, or perform an interventional radiological procedure.

balloon catheter

A multi-lumened catheter surrounded by a balloon. The balloon may be expanded by injecting air, saline, or contrast medium.

Bozeman-Fritsch catheter

See: Bozeman-Fritsch catheter

Broviac catheter

Broviac catheter.

cardiac catheter

A long, fine catheter specially designed for passage through the lumen of a blood vessel into the arteries or chambers of the heart.
See: cardiac catheterization

caudal catheter

Caudal anesthesia.

central catheter

A catheter inserted into a central vein or artery for diagnostic or therapeutic purposes.
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CENTRAL VENOUS CATHETER: A tunneled central venous catheter is inserted through subcutaneous tissue in the chest wall into the jugular or subclavian vein
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central venous catheter

A catheter inserted into the superior vena cava to permit intermittent or continuous monitoring of central venous pressure, to administer fluids, medications or nutrition, or to facilitate obtaining blood samples for chemical analysis. See: illustration

Patient care

Health care professionals must use caution to prevent life-threatening complications when inserting and maintaining a central line. The subclavian approach to the placement of a central line is preferred, because femoral placements may be complicated by deep venous thrombosis, and internal jugular sites carry an increased risk of infection. Sterile technique is a requirement during insertion. The skin should be prepared with chlorhexidine-gluconate (2%) or povidone-iodine. Ultrasound guidance improves the likelihood of entering the desired vein without injury to neighboring structures. With or without radiological guidance, the best results are obtained by practitioners who perform the procedure frequently. After the catheter is inserted, it should be firmly sewn to the skin to keep it from migrating in and out of the insertion site. An antibiotic impregnated patch covered by a sterile dressing should be placed at the insertion site. The catheter should be manipulated as infrequently as possible during its use. Dressing changes are carried out using sterile technique. IV tubing and solutions and injection caps also should be changed as required by the agency’s protocol. Health care professionals are responsible for preventing, assessing for, and managing central venous therapy complications (e.g., air embolism; cardiac tamponade; chylothorax, hemothorax, hydrothorax, or pneumothorax; local and systemic infections; and thrombosis). Documentation should include preprocedure and postprocedure physical assessment of the patient, catheter type and size, insertion site location, x-ray confirmation of the placement, catheter insertion distance (in centimeters), and the patient’s tolerance of the procedure. Maintenance care procedures also should be fully documented. The site should be carefully inspected for inflammation, and any drainage should be cultured. When catheter-related infections are suspected, the catheter tip provides valuable information about infection sources in cases of sepsis. The tip should be cut off with sterile scissors and dropped directly into a sterile specimen container.


condom catheter

A specially designed condom that includes a collection tube attached to the distal end. The tubing carries urine to a collecting bag. Its use prevents men with urinary incontinence from soiling clothes or bed linens.


Continual use of this device may excoriate the skin of the penis.
See: Catheter: External Condom

double-channel catheter

A catheter providing for inflow and outflow.

elbowed catheter

Prostatic catheter.

eustachian catheter

A catheter passed into the eustachian tube through the nasal passages to ventilate the middle ear.

female catheter

A catheter about 5 in (12.7 cm) long, used to pass into a woman's bladder.

Foley catheter

See: Foley catheter

glide catheter

A catheter inserted into the ureter to remove impacted kidney stones. A lubricated wire is advanced past the obstructing stone. The glide catheter is mounted on the wire, moved toward the kidney beyond the stone, and used to snare and retrieve the stone.

guide catheter

A catheter that makes it easier to enter that vessel with other devices or instruments. Guide catheters are used to facilitate the placement of lasers, stents, and balloons for angioplasty.

heparin-bonded catheter

A pulmonary artery catheter with a heparin coating to reduce the risk of thrombus formation.

Hickman catheter

See: Hickman catheter

impregnated catheter

A catheter coated with a medication to prevent complications of prolonged insertion in the body. Commonly used coatings include antibiotics and antiseptics.

indwelling catheter

Any catheter that is allowed to remain in place in a vein, artery, or body cavity.

indwelling pleural catheter

Pleural catheter.

intra-aortic catheter

See: intra-aortic balloon counterpulsation

intrauterine pressure catheter

Abbreviation: IUPC
A catheter inserted into the uterus of a woman during labor, when labor is protracted, arrested, or when the force of uterine contractions are difficult to monitor indirectly.

intravenous catheter

A catheter inserted into a vein to administer fluids or medications or to measure pressure.

Karman catheter

See: Karman catheter

male catheter

A catheter 12 to 13 in (30.5 to 33 cm) long, used to pass into a man's bladder.

pacing catheter

A catheter inserted most commonly into the right side of the heart via the brachial, femoral, internal jugular, or subclavian vein for temporary pacing of the heart. The pacing wires or leads provide the electrical stimulus from an external source (a pulse generator).

peripherally inserted central venous catheter

Abbreviation: PICC, PICC line
A soft, flexible central venous catheter, inserted in a vein in the arm and advanced until the tip is positioned in the axillary, subclavian, or brachiocephalic vein. It may also be advanced into the superior vena cava. A PICC is commonly used for prolonged antibiotic therapy, total parenteral nutrition, continuous opioid infusion, or intermittent chemotherapy.

pharyngeal suction catheter

A rigid catheter used to suction the pharynx during direct visualization. Synonym: Yankauer suction catheter

pleural catheter

A small chest catheter inserted between the parietal and visceral pleura and used to drain recurrent pleural effusions, e.g., in patients with cancer.
Synonym: indwelling pleural catheter

presternal catheter

A catheter used for peritoneal dialysis that exits the chest instead of the lower abdomen. It is made of two silicone rubber tubes joined at the implantation site by a titanium connector that links its abdominal and presternal parts.

prostatic catheter

A catheter, 15 to 16 in (38 to 40.6 cm) long, with a short elbowed tip designed to pass prostatic obstruction. Synonym: elbowed catheter

pulmonary artery catheter

A catheter inserted into the pulmonary artery to measure pulmonary artery pressures, pulmonary capillary wedge pressure, and, indirectly, left atrial pressure and cardiac output.

self-retaining catheter

A bladder catheter designed to remain in place (e.g., a Foley catheter).
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SUPRAPUBIC CATHETER: used to drain urine

suprapubic catheter

A catheter that permits direct urinary drainage from the bladder through the lower abdominal wall from a surgically fashioned opening located just above the pubic symphysis. Suprapubic urinary diversion is typically but not exclusively used as a temporary means of decompressing the bladder when the urethra is obstructed, e.g., in children with congenital deformities of the penis or urethra, or in adults with bladder outlet obstruction. When it is used for this purpose, it is considered a bridge before definitive surgery. See: suprapubic aspiration of urine; illustration

Patient care

The nurse observes for hemorrhage or prolonged hematuria and signs of local or systemic infection. Aseptic technique is used during dressing or equipment changes. Bladder irrigation is performed as prescribed. Medications, e.g., analgesics, antispasmodics, and bowel stimulants, are administered as prescribed. The patient's ability to micturate is evaluated. Intake and output are monitored and recorded. Fluids are forced unless otherwise restricted to ensure passage of dilute urine.

Swan-Ganz catheter

See: Swan-Ganz catheter

Tenckhoff peritoneal catheter

See: Tenckhoff peritoneal catheter

triple-lumen catheter

Abbreviation: TLC
A central catheter containing three separate channels or passageways.

tunneled central venous catheter

An intravenous catheter inserted into the subclavian or internal jugular vein and then advanced into the right atrium or superior vena cava. The proximal end is tunneled subcutaneously from the insertion site and brought out through the skin at an exit site below the nipple line. Commonly used tunneled catheters include the Hickman and Broviac catheters.

umbilical vein catheter

A catheter placed in the umbilical vein of an infant to facilitate administration of medicines parenterally or to do an exchange transfusion.

vertebrated catheter

A catheter in sections to be fitted together so that it is flexible.

winged catheter

A catheter with little flaps at each side of the beak to help retain it in the bladder.

Word catheter

A rubber catheter with an inflatable balloon at its end, used to treat cysts or abscesses, e.g., Bartholin gland cysts in the vulva.

Yankauer suction catheter

See: Yankauer suction catheter

triple-lumen catheter

Abbreviation: TLC
A central catheter containing three separate channels or passageways.
See also: catheter


(kro?ma-tog'ra-fe) [ chrom- + -graphy]
The separation of two or more chemical compounds in a liquid or gaseous mixture by their removal at different rates based on differential solubility and adsorption. This separation is often accomplished by letting the chemicals percolate through a column of a powdered adsorbent or by passing them across the surface of an adsorbent paper, among other techniques.chromatographic (-mat?o-graf'ik), adjective

adsorption chromatography

Chromatography accomplished by applying the test material to one end of a sheet or column containing a solid. As the material moves, the various constituents adhere to the surface of the particles of the solid at different distances from the starting point according to their chemical characteristics.

column chromatography

A form of adsorption chromatography in which the adsorptive material is packed into a column.

gas chromatography

An analytical technique in which a sample is separated into its component parts between a gaseous mobile phase and a chemically active stationary phase.

gas-liquid chromatography

Abbreviation: GLC
Chromatography in which a gas moves over a liquid, and chemical substances are separated on the liquid by their different adsorption rates.

gel filtration chromatography

A type of column chromatography in which chemicals are separated via pores according to their molecular size.

high-performance liquid chromatography

Abbreviation: HPLC
Application of high pressure to liquid chromatography technique to increase separation speed and enhance resolution.
Synonym: high pressure liquid chromatography

high pressure liquid chromatography

High-performance liquid chromatography.

paper chromatography

Chromatography in which paper strips are used as the porous solid medium.

partition chromatography

Chromatography in which substances in solution are separated by being exposed to two immiscible solvents. The immobile solvent is located between the spaces of an inert material such as starch, cellulose, or silica. The substances move with the mobile solvent as it passes down the column at a rate governed by their partition coefficient.

thin-layer chromatography

Abbreviation: TLC
Chromatography involving the differential adsorption of substances as they pass through a thin layer or sheet of cellulose or some other inert compound.

thin-layer chromatography

Abbreviation: TLC
Chromatography involving the differential adsorption of substances as they pass through a thin layer or sheet of cellulose or some other inert compound.
See also: chromatography


1. The number of units in a sample or object.
2. To enumerate.

absolute granulocyte count

Abbreviation: AGC
The total number of neutrophils, basophils, and eosinophils in a specimen of blood.

absolute neutrophil count

Abbreviation: ANC
The actual number of neutrophils in a cubic millimeter of blood. The approximate normal range is 3000 to 6000 cells/mm3. This figure is measured before and after drugs are given that may lower neutrophil counts, such as those used in cancer chemotherapy. Generally, chemotherapy is not given unless the patient's ANC is greater than 1000. Patients with an ANC of less than 500 cells/mm3 are at high risk for infection. See: neutrophil


The development of fever in a patient with neutropenia secondary to chemotherapy is an indication for urgent medical evaluation and prompt institution of broad-spectrum antibiotics.

absolute phagocyte count

Abbreviation: APC
The number of phagocytes (neutrophils and monocytes-macrophages) in a cubic millimeter of blood. The APC is the sum of the neutrophils (segs and bands), monocytes, and macrophages times one hundredth (1/100) of the white blood cell count.
See: absolute neutrophil count; blood count

blood count

The number of red cells and leukocytes per microliter (µl) of whole blood. Normally, the number of erythrocytes in men averages 5 million/µl; in women, 4.5 million/µl. Prolonged exposure to high altitude increases the number. Leukocytes average 5000 to 10,000/µl. Platelets range from 140,000 to 400,000/µl. Hemoglobin (12 to 18 g/100 ml) and hematocrit (38% to 48%) are determined from samples of whole blood.

complete blood count

Abbreviation: CBC
A laboratory evaluation of all the cells that circulate in the blood, including the number and the hemoglobin content of red blood cells, the white blood cells (and their subtypes), and platelets. The typical CBC provides assessments of size and shape of red blood cells and platelets as well.

Patient care

The CBC is among the most common blood tests performed in the clinical laboratory and aids in the diagnosis of anemia and erythrocytosis, bleeding and the repletion of blood cells by transfusion, thrombocytopenia and thrombocytosis, and infections and leukemias. Blood is obtained for the test from venipuncture or aspiration from an indwelling vascular access or port. It is taken to the laboratory in a tube that contains the anticoagulant ethylenediaminetetraacetic acid (EDTA).

differential blood count

The number and type of white blood cells as determined by microscopic examination of a thin layer of blood on a glass slide stained to show the shape of the various cells. The number and variety of white cells in a sample of a given size are obtained. Even though the red cells are not counted by this method, their shape, size, and color can be evaluated. Some blood diseases and inflammatory conditions may be recognized in this way. In a differential count, the varieties of the leukocytes and their percentages normally should be: neutrophils (segmented), 40% to 60%; eosinophils, 1% to 3%; basophils, 0.5% to 1%; lymphocytes, 20% to 40%; monocytes, 4% to 8%.

pollen count

The concentration of grains of pollen found in the atmosphere on a given day in a specific location. The measurement is used by allergy sufferers to forecast the likelihood they will have allergic symptoms, e.g., sneezing, sniffling, or wheezing.

surgical count

Counting the exact number of sponges, instruments, and other materials before, during, and after an operation in order to reduce the likelihood of leaving an object inside a body cavity.

total lymphocyte count

Abbreviation: TLC
The number of lymphocytes in a specimen of blood. The count may be increased in clonal diseases such as chronic lymphocytic leukemia or decreased in diseases such as AIDS. In AIDS, decreases in the total lymphocyte count usually reflect a marked decline in the number of helper T4 cells.

total lymphocyte count

Abbreviation: TLC
The number of lymphocytes in a specimen of blood. The count may be increased in clonal diseases such as chronic lymphocytic leukemia or decreased in diseases such as AIDS. In AIDS, decreases in the total lymphocyte count usually reflect a marked decline in the number of helper T4 cells.
See also: count
Medical Dictionary, © 2009 Farlex and Partners


Abbreviation for total lung capacity.
Medical Dictionary for the Dental Professions © Farlex 2012