Body Fluids Lectures #1 & #2 2024 PDF

PHGY 209 BODY FLUIDS Dr. Melissa A. Vollrath [email protected] (514) 398-2410 McIntyre Room 1234 September 2024 Undergraduate Student Course Assistants USCAs Body Fluids, Transport Mechanisms & Blood August 30 – September 20...

PHGY 209 BODY FLUIDS Dr. Melissa A. Vollrath [email protected] (514) 398-2410 McIntyre Room 1234 September 2024 Undergraduate Student Course Assistants USCAs Body Fluids, Transport Mechanisms & Blood August 30 – September 20 Kalenga Lubembele [email protected] Jasmine Chen [email protected] Victoria Lu [email protected] Attend lectures and write practice questions monitor and participate in Discussion Board answer e-mails relevant to class material Fundamental Principle: At all levels of organization, functional activities are directed at maintaining HOMEOSTASIS, the relative constancy of the “Milieu Interieur” (internal environment) cells internal environment Claude Bernard 1813 - 1878 “Milieu Interieur” 1. Environment surrounding individual cells is vastly different from external environment 2. Internal environment remains relatively constant under conditions of health  The “Milieu Interieur” includes various body fluids Aspects of Body Fluids Volume Distribution Characteristics Functions  WATER is the most abundant single constituent of the body H2O 45% to 75% Body water is the medium in which… Solutes are dissolved Metabolic reactions take place  What accounts for the large variation in water content in different individuals? H2O 45% to 75%  % of Water in Various Tissues Skin 70% Muscle 75% Heart, Liver, Brain, Kidney 70-80% Bone 25% Fat adipose tissue 10%  Water as a Proportion of Total Body Mass Fat Fat Fat Water Water Water 60% 45% 75% Solids Solids Solids  If body water content is computed as a fraction of LEAN BODY MASS (excluding FAT) the differences between individuals become insignificant  Water as a Proportion of LEAN Body Mass Fat Fat Fat Water Water Water LEAN BODY MASS Solids Solids Solids  Standard Values for a Physiological Reference Individual 21-year-old, white male, 70-kg weight Must adjust for Age Sex Fat Weight Water 60% Solids Variations in body water with age and sex ~75% ~50% ~60% ~50% ~45% Body Water as % of total body mass AGE (years) MALE FEMALE Infant 65% 65% 10-18 59% 57% 18-40 61% 51% 40-60 55% 47% > 65 50% 45%  Calculations of Body Water For 70-kg Male % Water ~ 60% Absolute amount of water: 70 x 60 = 42 kg = ~ 42L 100 2L 42L  Calculations of Body Water For 70-kg Male % Water ~ 60% Absolute amount of water: 70 x 60 = 42 kg = ~ 42L 100 For 60-kg Female % Water ~ 50% Absolute amount of water: 60 x 50 = 30 kg = ~ 30L 100  Calculations of Body Water For 70-kg Male What if % Water ~ 60% it was70ax 60 = 42 kg = ~ 42L Absolute amount of water: 70-kg100 Female? For 70-kg Female % Water ~ 50% Absolute amount of water: x 50 = kg = ~ L 100  Calculations of Body Water For 70-kg Male % Water ~ 60% Absolute amount of water 70 x 60 = 42 kg = ~ 42L 100 For 70-kg Female % Water ~ 50% Absolute amount of water 70 x 50 = 35 kg = ~ 35 L 100 Is it important to know the body water percentage?  Knowing the amount of body water is necessary when administering water-soluble medication Dosing 10 mg/7 kg 70-kg Male: 42 L water = 42,000 mL Administer 100 mg medication Final concentration in body: 100/42,000 = 0.0024mg/mL 70-kg female: 35 L water = 35,000 mL Administer 100 mg medication Final concentration in body: 100/35,000 = 0.0029mg/mL  Administering water-soluble medication 60% Body Water 70-kg Male: 42 L water = 42,000 mL Administer 100 mg medication Final concentration in body: 50% 100/42,000 = 0.0024mg/mL = 2.4 µg/ml Body Water 70-kg female: 35 L water = 35,000 mL Administer 100 mg medication Final concentration in body: 100/35,000 =0.0029mg/mL = 2.9 µg/ml You should be able to convert units: 29 µg is 29 x 10⎼6 grams 0.0029 mg is 2.9 µg milli (m) micro (µ) nano (n) pico (p) 10 ⎼3 10⎼6 10⎼9 10⎼12  Administering water-soluble medication 60% Body Water 70-kg Male: 42 L water = 42,000 mL Administer 100 mg medication Final concentration in body: 50% 100/42,000 = 0.0024mg/mL = 2.4 µg/ml Body Water 70-kg female: 35 L water = 35,000 mL Administer 100 mg medication Final concentration in body: 100/35,000 =0.0029mg/mL = 2.9 µg/ml 45% Body 70-kg elderly female: 31.5 L water = 31,500 mL Water Administer 100 mg medication Final concentration in body: 100/35,000 =0.0032mg/mL = 3.2 µg/ml  Administering water-soluble medication 60% Body Water 70-kg Male: 42 L water = 42,000 mL Administer 100 mg medication Final concentration in body: 50% 100/42,000 = 0.0024mg/mL = 2.4 µg/ml Body Water 70-kg female: 35 L water = 35,000 mL Administer 100 mg medication Final concentration in body: 100/35,000 =0.0029mg/mL = 2.9 µg/ml 45% Body 70-kg elderly female: 31.5 L water = 31,500 mL Water Administer 100 mg medication Final concentration in body: 100/35,000 =0.0032mg/mL = 3.2 µg/ml  Administering water-soluble medication 60% Body Water 70 kg Male: 42 L water = 42,000 mL Administer 100 mg medication Final concentration in body: 100/42,000 = 0.0024mg/mL 50% Body Water 70 kg female: 35 L water = 35,000 mL Dosing Administer 100 mg medication Final concentration in body: 100/35,000 =0.0029mg/mL 10 mg/7 kg 45% Body 70 kg elderly female: 31.5 L water = 31,500 mL Water Administer 100 mg medication Final concentration in body: 100/31,500 =0.0032mg/mL = 3.2µg/ml 75% Body 70-kg very thin male: 52.5 L water = 52,500 mL Water Administer 100 mg medication Final concentration in body: 100/45,500 =0.0019mg/mL = 1.9µg/ml  Administering water-soluble medication 60% Body Water 70 kg Male: 42 L water = 42,000 mL Administer 100 mg medication Final concentration in body: 100/42,000 = 0.0024mg/mL 50% Body Water 70 kg female: 35 L water = 35,000 mL Dosing Administer 100 mg medication Final concentration in body: 100/35,000 =0.0029mg/mL 10 mg/7 kg 45% Body 70 kg elderly female: 31.5 L water = 31,500 mL Water Administer 100 mg medication Final concentration in body: 100/31,500 =0.0032mg/mL = 3.2µg/ml 75% Body 7-kg infant: 5.25 L water = 5,250 mL Water Administer 10 mg medication Final concentration in body: 10/5,250 =0.0019mg/mL = 1.9µg/ml Body Water remains constant in health Body Water is in a “Dynamic Steady State” Individual Internally, between different compartments External Environment  Water Balance INTAKE OUTPUT Oral fluid 1.2L Oral intake 1.1L as food Oxidative 0.4L water from metabolism e.g. C6H12O6 + 6O2 6CO2 + 6H2O + energy TOTAL = 2.7L  Water Balance INTAKE OUTPUT Oral fluid 1.2L 0.4L Lungs Oral intake 1.1L 0.5L Skin passive evaporation as food Insensible Oxidative 0.4L Facultative water from 1.2L metabolism 0.5L Kidneys (urine) 0.1L Stool (feces) Sensible TOTAL = 2.7L TOTAL = 2.7L  Water Balance INTAKE OUTPUT Oral fluid 1.2L 0.4L Lungs Oral intake 1.1L 0.5L Skin passive evaporation as food Obligatory Oxidative 0.4L Facultative water from 1.2L metabolism 0.5L Kidneys (urine) 0.1L Stool (feces) TOTAL = 2.7L TOTAL = 2.7L  Obligatory vs. Facultative Losses Obligatory losses ~ 1.5 L of water/day Required insensible lungs and skin ~ 1.0 L sensible urine + stool ~ 0.5 L Facultative losses vary with intake Necessary to maintain balance urine the kidney is the key homeostatic organ for water balance  Water Balance INTAKE OUTPUT Oral fluid 1.2L 0.4L Lungs Oral intake 1.1L 0.5L Skin passive evaporation as food Obligatory another type Sweat of sensible loss Oxidative 0.4L Facultative water from ?? metabolism 0.5L Kidneys (urine) 0.1L Stool (feces) TOTAL = 2.7L TOTAL = 2.7L Insensible Perspiration Sweating 1. Pure water 1. Electrolyte solution 2. Passive evaporation 2. Active secretion affected by ambient temperature & relative humidity 3. Entire skin surface 3. Sweat glands present even in individuals lacking sweat glands 4. Continuous and obligatory 4. Activated by heavy work or high temp Normally, the individual is in water balance Adult: over 24 hours water turnover is 3-4% of total body weight Infant: over 24 hours water turnover is ~10% of total body weight Body water volume is remarkably Constant under conditions of health This helps maintain… - normal solute concentrations - normal blood volume and pressure adequate supply of O2 to tissues  A Negative Water Balance Water Loss > Water Intake 1. Reduced Intake 2. Excessive Loss from Gut 3. Excessive Sweating 4. Excessive Loss in Expired Air example: dry air at high altitudes 5. Excessive Loss in Urine Water “Intoxication” Water Intake > Water Loss 1. Excessive Intake 2. Renal System Failure Body Water is in a “Dynamic Steady State” Individual Internally, between different compartments External Environment  PHGY 209 BODY FLUIDS Dr. Melissa A. Vollrath (514) 398-2410 [email protected] September 2024 Undergraduate Student Course Assistants USCAs Body Fluids, Transport Mechanisms & Blood August 30 – September 20 Kalenga Lubembele [email protected] Jasmine Chen [email protected] Victoria Lu [email protected] Check out the discussion board!  Drs. Melissa Vollrath and Alvin Shrier Monday Wednesday Friday TOPIC August 28 30 Course Overview, September 2 4 Homeostasis Labour Day - No Class & Body Fluids 6 Transport 9 Mechanisms 11 13 Blood 16 18 20 23 25 27 30 October 2 Immunology 4 End-of-Section7 Quizzes open on9 the last day of each 11 section at 5 PM Nerve/Synapse NOTE: Body14 16 Fluids/Transport Mechanism 18 Quiz is combined Thanksgiving - No Class Fall Break - No Class Fall Break - No Class Opens21Monday, Sept.9 at 23 5 PM. Open for 5 days. 30 Closes (= Due) Saturday Sept. 14 at 5 PM. 25 You have two28 hours to complete30the quiz once you open November 1 it. CNS/Sensory ONLY ONE ATTEMPT. 4 6 8 and CLICK “submit” 11 BEFORE THE DEADLINE 13 15 Cognitive/Motor 18  Physiology 209 Body Fluids Aug. 30 – Sep. 4 Body Fluids/Transport Mec Transport Mechanisms End-of-Section Quiz Sept. 6 – 9 Opens 5 PM on Sept. 9 Blood Sept. 11 – 20  BODY FLUIDS Lecture 1 Summary Milieu Interieur & Homeostasis Body Water – Variations with Age, Sex and Body Fat Water Balance – ”dynamic steady-state” Intake vs. Output Obligatory vs. Facultative Losses Sweat is neither obligatory nor facultative – but is an output Negative Water Balance vs. Water Intoxication  Water Balance INTAKE OUTPUT Oral fluid 1.2L 0.4L Lungs Oral intake 1.1L 0.5L Skin passive evaporation as food Insensible Oxidative 0.4L Facultative water from 1.2L metabolism 0.5L Kidneys (urine) 0.1L Stool (feces) Sensible TOTAL = 2.7L TOTAL = 2.7L  Water Balance INTAKE OUTPUT Oral fluid 1.2L 0.4L Lungs Oral intake 1.1L 0.5L Skin passive evaporation as food Oxidative 0.4L Facultative water from 1.2L metabolism 0.5L Kidneys (urine) 0.1L Stool (feces) TOTAL = 2.7L TOTAL = 2.7L  Water Balance INTAKE OUTPUT Oral fluid 1.2L + 1 L 0.4L Lungs = 2.2 L Oral intake 1.1L 0.5L Skin passive evaporation as food Oxidative 0.4L Facultative water from 1.2L 2.2L metabolism 0.5L Kidneys (urine) 0.1L Stool (feces) TOTAL = 2.7L = 3.7 L TOTAL= 3.7 = 2.7L L  WATER BALANCE INTAKE OUTPUT Oral fluid 1.2L + 1 L 0.4L Lungs = 2.2 L Oral intake 1.1L 0.5L Skin passive evaporation as food Oxidative 0.4L 0.5L Kidneys water from metabolism 0.1L Stool (feces) TOTAL = 2.7L = 3.7 L TOTAL =  WATER BALANCE INTAKE OUTPUT Oral fluid 1.2L + 1 L 0.4L Lungs = 2.2 L Oral intake 1.1L 0.5L Skin as food + 0.5L of Sweat Oxidative 0.4L 0.5L Kidneys water from metabolism 0.1L Stool (feces) TOTAL = 2.7L = 3.7 L TOTAL =  WATER BALANCE INTAKE OUTPUT Oral fluid 1.2L + 1 L 0.4L Lungs = 2.2 L Oral intake 1.1L 0.5L Skin as food + 0.5L of Sweat Oxidative 0.4L 0.5L Kidneys water from 1.7L Facultative metabolism 0.1L Stool (feces) TOTAL = 2.7L = 3.7 L TOTAL = 3.7 L Body Water is in a “Dynamic Steady State” Individual Internally, between different compartments External Environment  Body Water Compartments Total Body Water = 60% of Body Mass There are 2 Major Compartments One Major Compartment is subdivided into 2 Major subcompartments 2 Minor subcompartments The compartments differ in… Size Volume Composition Function  Body Water Compartments and Subcompartments are NOT rigidly isolated chambers The compartments are continuously interacting in a dynamic fashion… with water exchanging freely between them  Body Water Compartments Total Body Water = 60% of Body Mass Intracellular Fluid = ICF Extracellular Fluid = ECF 2/3 1/3 Aggregate of fluid bound by internal surfaces of all cell membranes ICF = 40% of Body Mass ECF = 20%  Body Water Compartments Total Body Water = 60% of Body Mass = 42 L Intracellular Fluid = ICF Extracellular Fluid = ECF 2/3 1/3 ~ 28 L ~14 L ICF = 40% of Body Mass ECF = 20% The ECF compartment is subdivided into 2 Major and 2 Minor subcompartments Plasma Interstitial Fluid (ISF) Lymph Transcellular Fluid Whole Centrifuged Blood Blood Plasma the fluid medium, in which blood cells are suspended Plasma Buffy Layer WBCs, Platelets Red Blood Cells (RBCs)  Hematocrit (Ht) The percentage of Blood Volume that is 100 occupied by Red Blood Cells (erythrocytes) 100 height of erythrocyte column height of whole blood column 55 Normal Value: ~ 45% 45 Ht = Packed Cell Volume (PCV) The ECF compartment is subdivided into 2 Major and 2 Minor subcompartments Plasma Interstitial Fluid ISF Lymph Transcellular Fluid  Body Water Compartments Major Subcompartments ISF =15% 5% Intracellular Fluid = ICF Interstitial P Fluid = ISF L A S M A ICF = 40% of Body Mass ECF = 20% Interstitial Fluid = true “Milieu Interieur” The fluid which percolates between individual cells  Body Water Compartments Major Subcompartments ISF =15% 5% Intracellular Fluid = ICF Interstitial P Fluid = ISF L A S M A ICF = 40% of Body Mass ECF = 20%  Body Water Compartments Major Subcompartments In a 70 kg male ISF =15% 5% Intracellular Fluid = ICF Interstitial P Fluid = ISF L A S M A 28 L 10.5 L 3.5 L ICF = 40% of Body Mass ECF = 20% The ECF compartment is subdivided into 2 Major and 2 Minor subcompartments Plasma Interstitial Fluid ISF Lymph Transcellular Fluid Interstitial Fluid and Lymphatic Drainage  Lymphatic System A network of blind-ended terminal tubules coalesce to form larger lymphatic vessels converge to form large lymphatic ducts drain into the large veins in the chest Lymph Volume ~1-2% of ECF  Transcellular Fluid Aggregate of small fluid volumes secreted by specific epithelial cells that line some body cavities These fluids have specialized functions Volume < 1-2 % of ECF Does not contribute significantly to overall water exchanges; local changes do not affect body fluid balance * Locally, transcellular fluid plays an important role in function  Body Water Major and Minor Subcompartments Transcellular Fluid Lymph ISF =15% 5% Intracellular Fluid = ICF Interstitial P Fluid = ISF L A S M A ICF = 40% of Body Mass ECF = 20%  Body Fluids 1. Total Volume remains CONSTANT 2. Relative Distribution between compartments remains CONSTANT Total H2O ICF ECF ISF Plasma (% Body Weight) 60% 40% 20% 15% 5% 3. Compartments are in a state of DYNAMIC equilibrium  Methods to Determine Compartment Volumes 1. Direct 2. Indirect Indicator Dilution Method V=πr2 ☓ h ? h 2r Indicator Dilution Method Q(g) V=πr2 ☓ h ? h 2r Indicator Dilution Method Q(g) V=πr2 ☓ h h V = Q/c c (g/ml) 2r Indicator Dilution Method we need to know: (1) The total quantity of test substance introduced (2) The concentration of the substance/unit volume of fluid, after dispersion V = Q/c Indicator Dilution Method 1. Introduce known quantity (Q) of indicator into vein 2. Allow time to equilibrate 3. Remove known volume of blood, and centrifuge to obtain plasma 4. Measure concentration © in unit volume of plasma 5. Calculate V = Q/c Indicator Choice Non-toxic Total Diffuse readily, distribute Body evenly throughout I C Water compartment(s) to be F measured Induce no changes in Cell membrane distribution of water E ISF between compartments C F Capillary wall Easy to measure its Plasma concentration  Total Body Water Antipyrine ICF D2O T2 O Cell membrane ISF ECF Capillary wall Plasma Example: Total Body Water Measurement Indicators: Antipyrine, D2O, or T2O Q = 50 ml D2O c = 0.001 ml D2O/ml plasma Since V= Q/c Therefore, V = 50/0.001 = 50,000 ml = 50 L NORMAL AMOUNT BODY WATER FOR 70 kg man: ~ 42 L  Total Body Water Antipyrine ICF D2O T2 O Cell membrane Total ECF inulin, sucrose, ISF ECF mannitol Capillary wall Plasma Example: ECF Compartment Measurement Indicators: Radioactively labeled INULIN, SUCROSE or MANNITOL NORMAL ECF VALUE ~ 14 L  Total Body Water (Antipyrine, D2O, T2O) ICF Cell membrane Total ECF inulin, sucrose, ISF ECF mannitol Capillary wall Total Plasma Evans’ Blue Plasma Example: Plasma Volume Measurements Indicators: Evans’ Blue (T1824) or I131-Albumin Q = 200 mg Evans’ Blue c = 0.055 mg/ml plasma V = Q/c = 200/0.055 = 3600 ml = 3.6L Normal Plasma Volume Value ~ 3.5L *In a clinical situation… must correct for any amount which has been removed from body by metabolism or excretion during the time allowed for mixing. ICF and ISF Volume Determinations ICF ? ICF Total Body Water – ECF = ICF 42 L – 14 L = 28L ISF ? ECF – Plasma = ISF ISF E 14 L – 3.5 L = 10.5 L C F plasma  PROBLEM Total Plasma Volume = 3L Hematocrit (Ht) = 40% (% of Blood Volume occupied by RBCs) What is Total Blood Volume? Body fluids are essentially aqueous solutions of inorganic ions with variable amounts of protein.  Body Fluids – Ionic Composition ICF ECF ECF Plasma ISF 0.9% NaCl [dilute sea water?] ICF – High in K+ (and Mg++) ECF – High in Na+ and Cl- but low in Na+ and Cl- but low in K+ Artificial Physiological Solutions substitute for plasma/ISF Physiological Saline = 0.9% NaCl 9g NaCl + H20 to make up 1 L Locke-Ringer Solution 9g NaCl 0.4 g KCl Ringer’s Solution 0.2 g CaCl2 8.6 g NaCl 0.2 g MgCl2 0.3 g KCl 0.5 g NaHCO3 0.3 g CaCl2 0.5 g dextrose + H20 to make up 1 L + H2O to make up 1 L You do not need to know these other solutions UNITS OF CONCENTRATION PLEASE REVIEW For Dr. Shrier’s Lectures See also: Section 2.3 Vander  UNITS OF CONCENTRATION 1. AMOUNT (MASS) of Solute that it contains example: 1 g % = 1 g solute in 1 dl (100 ml) of water 2. NUMBER OF SOLUTE MOLECULES that it contains example: 1 Mol = gram molecular weight/1 L of H 2O MOLARITY = weight in g/gram molecular weight/ 1 L H 2O 3. NUMBER OF REACTIVE UNITS (number of charges/unit volume) example: Equivalent = Molarity of Ion x Valency  UNITS OF CONCENTRATION 1. AMOUNT (MASS) of Solute that it contains example: 1 g % = 1 g solute in 1 dl (100 ml) of water 1 g NaCl in 100 ml water = 1% solution of NaCl 10 g sucrose in 100 ml water = 10% solution of sucrose  UNITS OF CONCENTRATION 2. NUMBER OF SOLUTE MOLECULES that it contains example: 1 Mol = gram molecular weight/1 L of H2O MOLARITY of solution = weight (g) of solute/gram molecular weight/1 L H2O example: 58.5 g of NaCl in 1 L of solution = 1 M solution 23 + 35.5 29.2 g NaCl in 1 L of solution = 0.5 M solution A 1 M solution of a given solute has exactly the same number of molecules (6 x 1023, Avogadro’s number) as a 1 M solution of any other solute MOLALITY (m) - gives the number of moles of solute dissolved in 1kg solvent MOLARITY (M) - refers to the amount of solute in a specific amount of solution, whereas MOLALITY - refers to the amount of solute dissolved in a specific amount of solvent  UNITS OF CONCENTRATION 3. NUMBER OF REACTIVE UNITS (number of charges/unit volume) An Equivalent (Eq) = molarity of ion x valency of ion example: Na+ (with valency = 1), has 1 equivalent/mole Ca++ (with valency = 2), has 2 equivalents/mole 1 milliEquivalent (mEq) = 1/1000 of an equivalent 1. The Viability of Cells depends on the relative Constancy of the “Internal Environment” (the “Milieu Intérieur”) 2. The Viability of Cells requires EXCHANGES with the internal and (ultimately) the external environment Movement of Materials Between Compartments GI tract skin lungs plasma kidneys ISF capillary wall cell membrane ICF  “Barriers” to Transport Between ICF and External Environment 1. Cell (plasma) membrane barrier between ICF and ECF 2. Capillary wall barrier between ECF and plasma, and between plasma and the external environment next lecturer Dr. Alvin Shrier