Chapter 3 - Fluids, Electrolytes and acid-base Flashcards
What percentage of body weight does total body water (TBW) represent in adult horses?
60%
What percentage of body weight does total body water (TBW) represent in foals?
70%
What proportion of TBW does the extracellular fluid (ECF) volume represent in adult horses?
One third (20% of the BW)
Which component forms the largest part of the ECF?
Interstitial fluid (two thirds, 40% of BW)
What is the normal volume of gastrointestinal secretion in a 500-kg horse?
About 100 L every 24 hours
What is the blood volume in fit horses as a percentage of body weight?
14%
What is the normalblood volume as a percentage of body weight in sedentary horses?
8% in sedentary and 14% in sport horses
In neonates, blood volume represents what percentage of body weight?
15%
What is the osmotic pressure generated mainly by proteins in the plasma called?
Colloid osmotic pressure (COP)
The ECF is composed by what?
interstitial fluid (75%),
plasma (25%) lymph,
transcellular fluids such as synovial, pleural, abdominal, and cerebrospinal fluids (<1%).
The overall concentrations of anions and cations have to be ____________ in all fluids
The overall concentrations of anions and cations have to be equal in all fluids, including plasma (sum of all anions = sum of all cations)
In plasma what is the main anion and the main cation
In plasma, sodium is the main cation and chloride the main anion
n plasma what is the main anion and the main anion
bicarbonate and chloride are the main anions
Proteins have positve or negative charge?
Proteins have a negative charge and contribute
to the anions.
The interstitial fluid accounts for ___% of the ECF
The interstitial fluid accounts for about 75% of the ECF, and the components with significant concentrations
are sodium, bicarbonate, and chloride
The composition of Ions the ICF
the important cations are potassium and magnesium, and the important anions are phosphates and proteins
Definitation of osmolality
Osmolality is defined as the concentration of osmotically active particles in solution per kilogram of solvent (mOsm/kg)
definition of osmolarity
is the number
of particles of solute per liter of solvent (mOsm/L)
Normal plasma
osmolality
from 275 to 312 mOsm/kg
what is the Starling’s equation?
**Kf **is the filtration coefficient, which varies depending on the surface available for filtration and the permeability of the capillary wall; **Pcap and Pint **represent the hydrostatic pressures in the capillary bed and in the interstitial compartment, respectively;
πp and πint represent the oncotic pressure in the plasma and interstitial fluid, respectively; and σ is the reflection coefficient of proteins across the capillary wall
**Kf ** is the filtration coefficient, which varies depending on the
depending on the surface available for filtration and the permeability of the capillary wall
what Pcap and Pint
Pcap and Pint represent the hydrostatic pressures in the capillary bed and in the interstitial compartment, respectively;
Colloid osmotic pressure
(COP) is generated mainly by
proteins, albumin
What is the normal COP for foals and adults?
Normal values of 15.0 to 22.6 mm Hg for foals
Normal values of 19.2 to 31.3 mm Hgfor adults