Understanding Anesthesiology - The Global Regional Anesthesia ...

Interactive 1.1 Body water distribution and fluid management
redistribution is only 15-30 minutes, so it must be given
at a rate that accounts for its extravasation from the intravascular
space.
Colloids replace blood loss in a 1:1 ratio, assuming normal
membrane permeability. The use of colloids is generally
reserved for cases where greater than 20% of the
blood volume needs to be replaced or when the conse-
Table 4 Partitioning of various intravenous fluid solutions
TYPE OF
FLUID
ECF=1/3 TBW
ICF = 2/3
TBW
IVF=1/4 ECF IF=3/4 ECF ICF
“Tank of water” concept and drawing developed by Dr. Kinsey
Smith. Animated slides created by Dr. Rob Whyte.
Slides used with permission from both.
expansion than D5W or 2/3:1/3. Because of the partitioning
in the extracellular compartment, they must be
given in a 3-4:1 ratio to the estimated blood loss. Administration
of large amounts of N/S results in metabolic
acidosis and should be avoided. R/L contains 4
meq/L potassium, and should be avoided in patients
with renal failure. Glucose-containing solutions should
only be used for specific indications (such as to maintain
stable glucose levels in patient with diabetes mellitus
or hepatic disease), and should be based on known
glucose requirements. Finally, the half-life of crystalloid
1000 cc D5W 83 cc 250 cc 667 cc
1000 cc 2/3 :1/3 139 cc 417 cc 444 cc
1000 cc N/S OR
R/L
500 cc 5%
ALBUMIN
100 cc 25%
ALBUMIN
500 cc
PENTASPAN
250 cc 750 cc 0
500 cc 0 0
500 cc -400 cc 0
750 cc -250 cc 0
1 UNIT RCC 400 cc 0 0
TBW = total body water, ECF = extracellular fluid, ICF = intracellular
fluid, IVF = intravascular fluid, IF = interstitial fluid, RCC= red cell
concentrates.
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