French catheter scale

French catheter scale

The French catheter scale (most correctly abbreviated as Fr, but also often abbreviated as FR or F) is commonly used to measure the outer diameter of cylindrical medical instruments including catheters. In the French Gauge system as it is also known, the diameter in millimeters of the catheter can be determined by dividing the French size by 3, thus an increasing French size corresponds with a larger diameter catheter. The following equations summarize the relationships:

D(mm) = Fr/3 or Fr = D(mm)*3

For example, if the French size is 9, the diameter is 3 mm. Note: the French scale is equal to the diameter in mm multiplied by three, not the circumference (diameter times π) as is sometimes thought.

This is contrary to needle-gauge size, where the diameter is 1/gauge inches; thus the larger the gauge needle, the more narrow the bore of the needle.The Stubs Iron Wire Gauge system is also commonly used in a medical setting and is in fact more common for measuring needles, even though many find the Stubs system to be more confusing because the scale is non-linear and inversely proportional.

The French Gauge was devised by Joseph-Frédéric-Benoît Charrière, a 19th century Parisian maker of surgical instruments, who defined the "diameter times 3" relationship.

See also

* French catheter scale chart


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • French catheter scale chart — The French catheter scale or French units (Fr) is commonly used to measure the outside diameter of needles, catheters, and other cylindrical medical instruments. 1 Fr is equivalent to 0.33 mm = .013 = 1/77 of diameter. Thus, the size in French… …   Wikipedia

  • Catheter — disassembled In medicine, a catheter (pronounced /ˈkæθɪtər/) is a tube that can be inserted into a body cavity, duct, or vessel. Catheters thereby allow drainage, administration of fluids or gases, or access by surgical instruments. The… …   Wikipedia

  • French — may refer to:*French people, inhabitants of France *French language, the language spoken widely in France and in former French colonies *People named French *The French, a bandFictional characters: *Joseph French, a Detective Inspector appearing… …   Wikipedia

  • French — See F. scale. * * * French french n, pl French a unit of measure equal to one third millimeter used in measuring the outside diameter of a tubular instrument (as a catheter or sound) inserted into a bodily cavity <the catheter shaft size is… …   Medical dictionary

  • catheter — 1. A tubular instrument to allow passage of fluid from or into a body cavity or blood vessel. SEE ALSO: line (4). 2. Especially a c. designed to be passed through the urethra into the bladder to drain it of retained …   Medical dictionary

  • Urinary catheterization — Intervention ICD 9 CM 57.94, MeSH …   Wikipedia

  • Hypodermic needle — A hypodermic needle is a hollow needle commonly used with a syringe to inject substances into the body. They may also be used to take liquid samples from the body, for example taking blood from a vein in venipuncture.A hypodermic needle is used… …   Wikipedia

  • Stubs Iron Wire Gauge — The Stubs Iron Wire Gauge system (also known as the Birmingham Wire Gauge) is used in medicine to measure the diameter of hypodermic needles, catheters, and suture wires. It was originally developed in early 19th century England for use in wire… …   Wikipedia

  • CH — Cette page d’homonymie répertorie les différents sujets et articles partageant un même nom.   Sigles d’une seule lettre > Sigles de deux lettres   Sigles de trois lettres   Sigles de quatre lettres …   Wikipédia en Français

  • Ch — Cette page d’homonymie répertorie les différents sujets et articles partageant un même nom. {{{image}}}   Sigles d une seule lettre > Sigles de deux lettres   Sigles de trois lettres …   Wikipédia en Français

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”