Body Fluids

1. What are the body fluid compartments, their measurements, and composition?

TBW%: M:70 F:40%, ECF: 15%, ICF: 45%, Major cations: Cl-, K+, Major anions: Na+, CO2

TBW%: M:40 F:30%, ECF: 25%, ICF: 35%, Major cations: H+, Ca2+, Major anions: Mg2+, SO4

TBW%; M:60 F:50 %

ECF: 20% , 14 l = interstitial fluid + plasma
-Intravascular (blood plasma, lymph) - 5%
-Extravascular - Interstitial - 15% (ultrafiltrate of plasma - less proteins)
Major cation: Na´+ , Anions: Cl-, HCO3-
F= fluid from which cells take up O2 and nutrients and discharge metabolites into

ICF: 40% - 28L (2/3)
Major cations: K+, Mg+
anions: Protein, organic phosphates

ECF vs. ICF

Na+: EC; 142 IC: 9
K+: E; 5 , I:135
Cl-: E:103, I: 9
-Seperated by membranes
-Permeable to water, but not so much to solutes Na+, Cl- , conc. of these = effective osmolarity for each compartment
-ECF effective osmolarity increase, cell shrink (ICF decrease) + vv.

Interstital fluid vs plasma fluid
-Fluid moves across capillary membranes
-Freely permeable to all plasma substances except proteins
= plasma protein conc. determine effective osmolarity

ECV vs. ICV
-ECV; Enlarge with net gain of body fluid, (decrease with net loss)
-ICV: Varies with effective osmolarity of EC-compartment, (increase osmolarity -> decrease ICV)

Measurements:
Dilution method
-Triated water: Total body water
-Mannitol: ECF
-Evans blue: plasma volume
Conc. in plasma measured,
Volume = amount of substance present/ conc. in plasma

TBW%: M:50 F:60%, ECF: 30%, ICF: 20%, Major cations: Ca2+, Mg2+, Major anions: HCO3-, PO4

Understanding the body fluid compartments, their measurements, and composition is essential in understanding the distribution of fluids in the human body. The correct answer provides the accurate percentages of total body water, extracellular fluid, and intracellular fluid, along with the major cations and anions present.

Explanation

Understanding the body fluid compartments, their measurements, and composition is essential in understanding the distribution of fluids in the human body. The correct answer provides the accurate percentages of total body water, extracellular fluid, and intracellular fluid, along with the major cations and anions present.

2. Blood: Specific Gravity

3) WBC: 1075

1) Specific gravity =relative density with respect to water
-Blood; 1056 ( 1052-1063) kg/m3
-Plasma; 1027
-RBC: 1090
Depends on:
-Ht , plasma proteins, water content of blood
Measurements ( indicate Hb content of blood)
-Direct; Pyconometers - blood vs. water equal volumes- ratio of wt. :> specific gravity
-Indirect
a) Hammar Schlags - Equalizing the 2 densities of miscible liquid to that of blood (chloroform, benzene)
b)
Philin van syke's Cu-sulphate method
-the specific gravity of blood is compared with solutions of known density

1) Plasma: 1060

2) RBC: 1020

Specific gravity of blood is related to its relative density compared to water, with variations based on factors like hematocrit, plasma proteins, and water content. Correct measurements involve comparing the density of blood with water using specific techniques like pyconometers or Hammar Schlags method.

Explanation

Specific gravity of blood is related to its relative density compared to water, with variations based on factors like hematocrit, plasma proteins, and water content. Correct measurements involve comparing the density of blood with water using specific techniques like pyconometers or Hammar Schlags method.

3. What factor primarily determines the viscosity of blood?

Amount of plasma in blood

Viscosity of Blood
-4-5x higher than water
(plasma- x1.8)
n= property of a fluids that measures its internal resistance to flow
-Primarily determined by hematocrit
( Ht ~45% - Viscosity: 4-5)
-Anemia: decreased viscosity - decreased peripheral resistance
-Polycytemia: increased n -

> In large vessels - Ht changes cause greater changes in viscosity ( Ht has little effect on peripheral resistance)

Temperature & Viscosity
-Increase T- Increase n
~2% inc. n - for every C

Flow:
-Low flow allows molecules to stick together which may increase viscosity

>High viscosity blood coagulate more easily

Viscosity is also affected by:
-plasma composition ( significant inc. in Ig's)
-resistance of cells to deformation ( abnormally rigid RBC's - hereditary spherocytosis)

Measurement:
-Viscometer

Blood pressure

Red blood cell count

Viscosity of blood is primarily determined by hematocrit, which is the percentage of red blood cells in the blood. Changes in hematocrit can significantly affect blood viscosity.

Explanation

Viscosity of blood is primarily determined by hematocrit, which is the percentage of red blood cells in the blood. Changes in hematocrit can significantly affect blood viscosity.

4. What does Hematocrit measure?

Hematocrit:
-% of RBC's in whole blood
Ht value = volume of cellular elements of blood in relation who whole blood volume
-Depends mainly on RBC count & RBC volume
M: 0.44 +/- 0.05
F: 0.38 +/- 0.04
Newborns: 50-60%

Meausurement:
-Enables also evaluation of other things; whole blood volume, MCV..
-Centrifugation
i)Classical method: Venous blood - centrifuge- capillary
(multiply by correction factor 0.92)
ii)Microhematocritic set

The level of platelets in the blood.

The oxygen carrying capacity of red blood cells.

The amount of white blood cells in whole blood.