MEASUREMENT OF BODY FLUID COMPARTMENTS
i) DILUTION PRINCIPLE: If a substance of known concentration and
volume is injected into a person's blood stream and a sample of his blood
is taken after a few minutes, the person's compartment volume can be
determined by measuring the new concentration.
Volume= Quantity of substance
Concentration of substance
ii) TOTAL BODY WATER: a) Deuterium oxide
b) Tritiated water
iii) ECF: a) Inulin
b) Sucrose
iv) ICF: can be determined by subtraction of ECF from total body water
OSMOLARITY: The number of osmoles dissolved in 1 L of solvent
OSMOLALITY: The number of osmoles dissolved in 1 kg of solution
OSMALARITY IS EASIER MEASUREMENT
OSMOLALITY IS ACCURATE MEASUREMENT
18% of NaCl calculate osmolarity?
Molarity=concentration
Molecular weight
=18 x 10/(23+35.5)= 0.31 mol/L
=0.31 x 2= 0.620 osmole/L x 1000= 620 mosmoles/L
(HYPERTONIC)
ELECTROCARDIOGRAM (ECG)
i) A graphic recording of the electrical activity of the heart
ii) P Wave: Atrial depolarization (rounded in shape, 0.12s)
iii) QRS Complex: Ventricular depolarization (0.12 s)
iv) T Wave: Ventricular repoilarization
v) U Wave: Ventricular repolarization (sometimes follows T Wave)
vi) P-R Interval (0.12-0.22 s): Electrical conduction period of heart
vii) Q-T Interval (0.39-0.44 s): Refractory Period of ventricles
, Determination of Heart Rate: small box= 0.04 s
Big box= 0.2 s
Count from R to R,
Big Box= 300/R-R interval
Small Box= 1500/R-R interval
BLOOD TYPES
Only A B O D
D determines +/-
MCV= Mean Corpuscular Volume
= PCV/ RBC count x 10 (80-100 femtoliters)
More than 100 Megaloblastic anemia & Vit. B12 & folic acid deficiency
Less than 80 is Iron deficiency anemia
MCH= Mean Corpuscular Hemoglobin
Amount of hemoglobin in one RBC
Hb/RBC count x 10 (27-35 picograms)
CAN NEVER BE MORE THAN 35
Less than 27 is Hypochromic (iron deficiency)
MCHC= Mean corpuscular hemoglobin concentration
Hb/PCV x 100 (30-34 %)
CAN NEVER BE MORE THAN 34%
Less than 30 is Hypochromic (iron deficiency)
Blood Volume= Plasma Volume x 100 (38-46%
females
100- hematocrit 42-50% males)
i) DILUTION PRINCIPLE: If a substance of known concentration and
volume is injected into a person's blood stream and a sample of his blood
is taken after a few minutes, the person's compartment volume can be
determined by measuring the new concentration.
Volume= Quantity of substance
Concentration of substance
ii) TOTAL BODY WATER: a) Deuterium oxide
b) Tritiated water
iii) ECF: a) Inulin
b) Sucrose
iv) ICF: can be determined by subtraction of ECF from total body water
OSMOLARITY: The number of osmoles dissolved in 1 L of solvent
OSMOLALITY: The number of osmoles dissolved in 1 kg of solution
OSMALARITY IS EASIER MEASUREMENT
OSMOLALITY IS ACCURATE MEASUREMENT
18% of NaCl calculate osmolarity?
Molarity=concentration
Molecular weight
=18 x 10/(23+35.5)= 0.31 mol/L
=0.31 x 2= 0.620 osmole/L x 1000= 620 mosmoles/L
(HYPERTONIC)
ELECTROCARDIOGRAM (ECG)
i) A graphic recording of the electrical activity of the heart
ii) P Wave: Atrial depolarization (rounded in shape, 0.12s)
iii) QRS Complex: Ventricular depolarization (0.12 s)
iv) T Wave: Ventricular repoilarization
v) U Wave: Ventricular repolarization (sometimes follows T Wave)
vi) P-R Interval (0.12-0.22 s): Electrical conduction period of heart
vii) Q-T Interval (0.39-0.44 s): Refractory Period of ventricles
, Determination of Heart Rate: small box= 0.04 s
Big box= 0.2 s
Count from R to R,
Big Box= 300/R-R interval
Small Box= 1500/R-R interval
BLOOD TYPES
Only A B O D
D determines +/-
MCV= Mean Corpuscular Volume
= PCV/ RBC count x 10 (80-100 femtoliters)
More than 100 Megaloblastic anemia & Vit. B12 & folic acid deficiency
Less than 80 is Iron deficiency anemia
MCH= Mean Corpuscular Hemoglobin
Amount of hemoglobin in one RBC
Hb/RBC count x 10 (27-35 picograms)
CAN NEVER BE MORE THAN 35
Less than 27 is Hypochromic (iron deficiency)
MCHC= Mean corpuscular hemoglobin concentration
Hb/PCV x 100 (30-34 %)
CAN NEVER BE MORE THAN 34%
Less than 30 is Hypochromic (iron deficiency)
Blood Volume= Plasma Volume x 100 (38-46%
females
100- hematocrit 42-50% males)
