BODY FLUIDS Flashcards
Survival of cells require:
- Constant volume and stable composition of the body fluids
- Total body fluid volume and solute should be constant
*Intake = output
______ ANALOGY
- Maintaining water homeostasis is a balancing act. The amount of water taken in must equal the amount of water lost.
WATER TANK
In steady state water intake= ______
water loss
______ - MAJOR COMPOSITION OF OUR
BODY
- ______% of the total body weight
- ______ liters ( 70 kg man)
- depends on age, gender, degree of obesity
WATER, 60, 42
2 major sources of body water:
Exogenous source
Endogenous source
2 major sources of body water:
______ source - ingested in the form of liquids or in the food (______ ml/day)
Exogenous, 2,100
2 major sources of body water:
______ source - synthesized in the body through oxidation of Carbohydrates (______ml/day)
Endogenous, 200
Total water intake - ______ml/day
2,300
Daily loss of body water:
Insensible fluid loss
Fluid loss in sweat
Water loss in feces
Water loss thru the kidneys (urine)
Daily loss of body water:
______
- Occurs continually in all living humans thru the skin and the lungs
Skin - by ______
• Minimized by the cornified layer of the skin-______ - excessive loss
• Normal: 300 - 400ml/day; 3-5 li/ day (burn victims)
Respiratory tract - by ______
• 300 - 400ml/day
• Greater loss of fluid from the lungs as the temperature ______ (cold weather where atmospheric vapor pressure is nearly 0)
Insensible fluid loss, diffusion, denudation, evaporation, decreases
Daily loss of body water:
______
- Highly variable - normal: ______ml/day
- Depends on physical activity and environmental temperature
- Hot weather or heavy exercise - ______ li/hr
Fluid loss in sweat, 100, 1-2
Daily loss of body water:
______
- = ______ml/day
- Increases in severe diarrhea
Water loss in feces, 100
Daily loss of body water:
______
- Most important means by which the body maintains a balance between fluid intake and output
- ______li/day - dehydrated person
- ______ li/ day with increase fluid intake
Water loss thru the kidneys (urine), 0.5, 20
Water occupies two main fluid compartments:
• Intracellular fluid (ICF)
• Extracellular fluid (ECF)
- Interstitial Fluid (IF)
- Plasma
- Transcellular Fluid
- Synovial, peritoneal, pericardial, intraocular, CSF
-1-2 L
TBW volume = ______ L, ______% body weight
40, 60
1/3 TBW 15 L, 20% body weight = ______
Extracellular fluid
2/3 TBW 25 L, 40% body weight = ______
Intracellular fluid
3/4 ECF 12 L, 80% of ECF = ______
Interstitial fluid
1/4 ECF 3 L, 20% of ECF = ______
Plasma
______ Fluid Compartment:
• Fluid of each cell contains almost the same concentration
Intracellular
______ Fluid Compartment:
• Constitutes approximately 40% of the total body weight ( 25 liters)
Intracellular
______ Fluid Compartment:
• Separated from the extracellular fluid by a selective membrane —- highly permeable to water only
Intracellular
______ Fluid Compartment:
• Contains K+, Phosphates, Mg+, SO4, Proteins
Intracellular
______ fluid compartment:
• All the fluids outside the cells
Extracellular
______ fluid compartment:
• Accounts for about 20% of the body weight
Extracellular
______ fluid compartment:
• =15 liters
______ 75% ( 12L)
______ 25% ( 3L)
- non cellular part of the blood
- communicates continuously with the interstitial fluid thru capillary membrane pores
Extracellular, Interstitial, Plasma
______ fluid compartment:
• Contains Na+, CI-, HCO3, Ca++
Extracellular
Each fluid compartment of the body has a distinctive pattern of ______
electrolytes
______ fluids are similar (except for the high protein content of plasma)
- ______ is the chief cation
- ______ is the chief anion
Extracellular, Sodium, Chloride
______ fluids have low sodium and chloride
- ______ is the chief cation
- ______ is the chief anion
Intracellular, Potassium, Phosphate
Each compartment must have almost the same concentration of positive charge (______) as of negative charge (______)
(______)
cations, anion, Electroneutrality
Positively charged ions slightly greater in plasma than the interstitial fluid due to ______
Donnan effect
*______ - plasma proteins (net negative charge) —binds cations ( Na, K+)-extra
amount of cations in the plasma
Donnan Effect
REGULATION OF FLUID EXCHANGE
- Distribution of fluid between IC compartment and the EC compartment is determined by:
______ effect of smaller solutes acting across the cell membrane (sodlum, chloride, and other electrolytes)
• the cell membranes are highly permeable to ______ but relatively impermeable to even small ions such as ______ and ______
• water moves across the cell membrane rapidly, and the intracellular fluid remains ______ with the extracellular fluid.
Osmotic, water, sodium, chloride, isotonic
______ - net diffusion of water from a region of high water concentration to a region of lower concentration
• The cell can either shrink or swell
OSMOSIS
______ - refers to the number of osmotically active particles in a solution rather than the molar concentration
Example: 1 mole of glucose = 1 osm/li
1 mole of NaCl = 2 osm/li)
Osmole
______ refers to the osmolal concentration of a solution expressed as osmoles per kilogram of water
Osmolality
______ - osmoles/ liter of solution
Osmolarity
______
• the precise amount of pressure required to prevent osmosis
Osmotic pressure
______
• amount of pressure that must be applied to prevent the net diffusion of water thru the membrane
Osmotic pressure
______
•Indirect measurement of the water and solute concentrations of a solution
Osmotic pressure
The higher the ______ of a solution, the lower the ______ but the higher the ______
*directly proportional to the concentration of osmotically active particles in the solution
*proportional to its osmolarity
osmotic pressure, water concentration, solute concentration
OSMOLARITY OF THE BODY FLUIDS
• 80% of the total osmolarity of the interstitial fluid and plasma is due to ______ and ______ ions
• 50% of the total osmolarity of the intracellular fluid is due to ______ ions
sodium, chloride, potassium
• Small changes in concentration of impermeant solutes in the extracellular fluid can cause tremendous change in cell volume
The body is trying to achieve ______
osmotic equilibrium
• ______ solution (less than 280 mosm/li)
- cell swells
Hypotonic
• ______ solution ( 280 mosm/li) - no change
Isotonic
• ______ solution ( more than 280mosm/li)
- cell shrinks
Hypertonic
Factors that can cause exchange in extracellular and intracellular volumes:
• Ingestion of water (over hydration)
• Dehydration
• Intravenous infusions of different types of solutions
• Loss of large amounts of fluid from the GI tract
(vomiting/diarrhea)
• Loss thru sweating or through the kidney
- ______ moves rapidly across cell membranes
- cell membrane is almost completely ______ to many solutes
water, impermeable
______ concentration - used by clinicians to assess patients fluid status
Plasma Na+
______ concentration - reasonable indicator of plasma osmolarity
Plasma Na+
Normal Na+ concentration: ______
142 meqs/ liter
______
- plasma Na+ concentration is below normal
- can result from loss of NaCl from the ECF or addition of excess water
Hyponatremia
CAUSES of Hyponatremia:
- diarrhea/ vomiting
- overuse of diuretics
- kidney diseases (excessive secretion of antidiuretic hormone
- Addison’s disease decrease secretion of hormone aldosterone)
______
- plasma Na+ concentration is above normal
- due to loss of water from the ECF or excess sodium in the ECF
Hypernatremia
CAUSES of Hypernatremia:
• diabetes insipidus ( lack of ADH)
• excessive sweating
• decreased water intake
• excessive secretion of aldosterone
______
- Presence of excess fluid in the body tissues
Occurs mainly in the ECF (interstitial )
May also involve intracellular fluids
EDEMA
______ EDEMA
______ swelling
• CAUSES
- depression of the metabolic systems of the tissues - lack of adequate nutrition to the cells
- decrease blood flow
- decrease 02 and nutrients
- depression of cell membrane ionic pumps excess Na+ ions inside the cells osmosis of water into the cells (______)
- inflammation
increase cell permeability → sodium and other ions diffuse into the interior of the cell → ______
INTRACELLULAR, Intracellular, CELL SWELLING, OSMOSIS
______ EDEMA
• Excess fluid accumulation in the extracellular spaces
Two General Causes:
- Abnormal leakage of fluid from the plasma to the interstitial spaces across the capillaries
- Obstruction of the lymphatics
(infections of lymph nodes, cancer surgeries)
______ - most common clinical cause of interstitial fluid accumulation
EXTRACELLULAR, Excessive capillary filtration
Major factors that increase capillary filtration:
Increased capillary hydrostatic pressure
Decreased plasma proteins
Increased capillary permeability
Blockage of Lymph Return
Major factors that increase capillary filtration:
______
- excessive kidney retention of salt and water,
- high venous pressure and venous constriction
- decrease arteriolar resistance
Increased capillary hydrostatic pressure
Major factors that increase capillary filtration:
______
- loss of proteins urine (______ syndrome)
- loss of proteins in the skin (burns, wounds)
- failure to produce proteins (liver diseases)
Decreased plasma proteins, Nephrotic
Major factors that increase capillary filtration:
______
- infections, prolonged ischemia, burns
Increased capillary permeability
Major factors that increase capillary filtration:
______
- Cancer
- Infections
- Surgery
Blockage of Lymph Return
______
• Most serious cause and most common cause of edema
Edema secondary to Heart failure
______
- Heart fails to pump blood normally from the veins to the arteries —– increase venous and capillary pressures —– increase capillary filtration —– edema
Edema secondary to Heart failure
______
- second most common
* injury to the renal glomeruli / kidney diseases —- failure to filter adequate amounts of fluid — salt and water retention —- EDEMA
Edema caused by kidney retention of salt and water
______
- a. failure to produce normal amounts of proteins ( liver diseases)
- b. leakage of proteins from the plasma/ kidneys
(infections, nephrotic syndrome)
- results from decreased plasma colloid osmotic pressure —- increased capillary filtration-edema ( protein concentration falls below 2.5 gms /di)
Edema caused by decreased plasma proteins
