Body Fluids Compartments PDF

B ODY F LU I D S C O M PA RT M E N T S Dr. Mohammad Zayed Dr. Hala Bagabir SLO Recognize the distribution and importance of body water. Define types of body fluids compartments. Describe the intracellular and extracellular compartments of the body. List composition...

B ODY F LU I D S C O M PA RT M E N T S Dr. Mohammad Zayed Dr. Hala Bagabir SLO Recognize the distribution and importance of body water. Define types of body fluids compartments. Describe the intracellular and extracellular compartments of the body. List composition of different body fluid compartments. F L U I D I N TA K E A N D OU T P U T Insensible H2O loss Input Output Sweat H2O Feces Urine T O TA L B O DY WA T E R What are the factors affecting total body water? B ODY C O M P OS I T I O N % OF B ODY B O DY C O M P O S I T I O N WEIGHT P ROT E I N, & R E L AT E D 18% S U B S TA N CE S FAT 15% MINERAL 7% WA T E R 60% F L U I D C O M PA RT M E N T S 2/3 (40% of TBW) 1/3 (20% of TBW)  F L U I D C O M PA RT M E N T S  6 0 % O F T O TA L B O DY W E I G H T Transcellular fluids ICF ECF 2% of TBWt 2/3 of TBW 1/3 of TBW 40% of TBWt 20% of TBWt Interstitial fluid Plasma 75% of ECF 25% of ECF 15% of TBWt 5% of TBWt TBW= total body water, TBWt= total body weight L E T ' S D O S O M E M AT H In Average 70 kg person calculate the volumes of the following in litres ? Total body water (TBW). Extracellular fluid (ECF). Intracellular fluid (ICF). Plasma volume. Interstitial fluid (ISF). TBW = 42 L S O L U T E S - D I S S O LV E D PA RT I C L E S 1. Electrolytes – charged particles A. Cations – positively charged ions Na+, K +, Ca ++, H + B. Anions – negatively charged ions Cl-, HCO 3- , PO 43- 2. Non-electrolytes - Uncharged Proteins, urea, glucose, O 2, CO 2 DIFFERENCES BETWEEN ICF & ECF Plasma ECF ICF Cation Na+ (mM) 142 145 15 K+ (mM) 4.4 4.5 140 Ca++ (mM) 1.2 1.2 0.0001 Mg++ (mM) 0.6 0.6 20 Anion Cl- (mM) 102 116 20 HCO3- (mM) 22 25 16 PO43- (mM) 1 1 100 Nutrients Proteins (g/dL) 7 1 16 Glucose (mM) 5.5 5.9 Very low pH 7.4 7.4 7.1 Osmolarity 270 - 300 270 - 300 270 - 300 mosmole/L PLASMA OSMOLARITY OsmolaRity vs osmolality All solutes produce osmotic power to hold water. Plasma is clinically accessible by [Na +] and the associated anions. Under normal conditions, ECF osmolarity can be roughly estimated as: POSM = 2 [Na +]p: 270 to 300 mOsm/L W hat is pure water osmola rity? W hat is sea water osmolarity? OSMOSIS TONICITY Is the osmolarity of solution in relation to that of body fluids. Isotonic solution Hypotonic solution Hypertonic solution Same osmolarity as Lower osmolarity Higher osmolarity plasma compared to plasma compared to plasma = 300 mOsm/L < 300 mOsm/L > 300 mOsm/L 0.9% NaCl : given in salt-water depletion (diarrhea & vomiting). 5% glucose : given in water loss as glucose is metabolized leaving water to correct hyperosmolarity.  EFFECT O F IS OTO NI C, H YPOTO NIC AN D H Y P E RT O N I C S O L U T I O N S T O E C F Remember fluids of cellular component of the blood (RBCs, WBCs & platelets) is considered ICF D I S O R D E R S O F H 2O B A L A N C E : D E H Y D R AT I O N Cells lose H2O to ECF by osmosis; cells shrink Excessive loss of H2O ECF osmotic from ECF pressure For how long?? T E S T YO U R U N D E R S TA N D I N G True or false: ↑ blood osmolarity occur as a result of dehydration. ↓ blood osmolarity increases in blood osmotic pressure. ↑ blood osmolarity is accompanied by an increase in ADH secretion. Osmosis is the movement of solutes down its concentration gradient. T E S T YO U R U N D E R S TA N D I N G Which solution causes RBCs shrinkage? A. Hypotonic solution. B. Isotonic solution. C. Hypertonic solution. EFFECT OF TONICITY ON RBCS H2O H2O no shift of H2O Hypotonic Isotonic Hypertonic REFERNCES Guyton & Hall Textbook of Medical Physiology, 13th ed., 2016 Ch.25, pp: 305-316. Watch: https://www.youtube.com/watch?v=sLArUSLu0n8