Body measurements

At 60 years of age you if male only have 50 body water instead of 60. A method has been developed by which body fluid volume changes can be assessed frequently after only one initial injection of the appropriate radioactive tracers. All exchanges of water and solutes with the external environment occur through the extracellular fluid ecf eg intravenous infusion and intake or loss via the gastrointestinal tract. 20150921 fluid compartments regulation of ecf volume fluid replacement duration. A known amount of a tracer is added to a compartment. The volumes of the various body fluid compartments can be estimated in a healthy adult as shown in figure 1 3.

If one were that way inclined one could also go on to read this indepth article by shoeller etal from 1980 full of thick juicy physiology. This volume is regulated by the movement of free water. The tracer is the patients own red cells which are tagged with radio chromium cr 51 red cellstypically a 10 ml sample of the subjects blood is incubated with a sodium chromate solution the label is taken up by the red cells and any excess in the solution is removed by dilution and centrifuging with removal of fluid. Extracellular fluid 27 189 litres. The plasma volume is calculated by evans blue technique the proportion of plasma and hematocrit is by centrifugation. 221 the dilution principle.

This volume is regulated by the movement of sodium. The intracellular fluid icf compartment is the system that includes all fluid enclosed in cells by their plasma membranes. Body fluids can be discussed in terms of their specific fluid compartment a location that is largely separate from another compartment by some form of a physical barrier. Briefly previously anesthetized animals were placed in a prone position on a temperature controlled 37 01 c non conductive surface with their fore and hindlimbs besides their body and tails. I have presented an oversimplified pictogram of this elegant process. Previous index next.

The extracellular fluid compartment volume. Intracellular fluid 33 231 litres. Measuring the extracellular fluid volume with ionic tracer. The fluid compartment volume. If plasma is x and its volume in body is y then plasmahematocrit100 the volume in body is v. Fluid physiology 22 measurement of compartment volumes.

Compartment volumes are measured by determining the volume of distribution of a tracer substance. Then make proportion calculation. An approach to the measurement of body fluid compartment volumes in non steady conditions in the rat. Determinations of body fluid compartment volumes with measured using the bis impedivet impedimed limited brisbane australia were performed as described previously smith et al 2009. Measuring total body water with radiolabelled tritium. Extracellular fluid volume measurement.

University of kentucky department of anesthesiology 5062 views 2943.