Ch 4

• Interstitial fluid (___% of TBW): - Fluid in the space ____ and _____ • Intravascular fluid (___% of TBW): - _____ (the fluid of the blood) • Lymph: - In between ____ and ____ fluids • Transcellular fluids: (____ % of TBW) - Synovial, intestinal, peritoneal, pleural, pericardial, intraocular fluids - Cerebrospinal fluid - Sweat and urine

15 between the cells, outside the blood vessels 5 blood plasma interstitial, intravascular negligible

Body weight: 1. ____-___% of body weight consist of solids, including: 1. Fat (adipose tissue) 2. Fat free (bone, cartilage, muscle) 2. ____-_____% of body weight consists of water • Total body water (TBW) is the sum of all fluids in the body • TBW is distributed into two functional compartments 1. _____ fluid 2. ____ fluid

40-50 50-60 intracellular extracellular

Pediatrics - ____% to ____% of body weight - Susceptible to significant changes in body fluids • Dehydration in newborns • Aging - ______ percent of total body water • Decreased free fat mass and decreased muscle mass • Renal decline • Diminished thirst perception

75-80 decreased

The _____ is usually subjected to rapid changes in osmolality, but the ____ is not • When ECF osmolality changes, water moves from one compartment to another until osmotic equilibrium is re-established

ECF,ICF

Fluid moves between the vascular, interstitial (ECF), lymphatic, and intracellular (ICF) spaces Fluid movement is a result of net filtration of water across semi-permeable membranes 1. The capillary membrane: from ____ to ____ 2. The plasma membrane: from ___ to ____ The fluid in each space exerts both hydrostatic and osmotic pressures

blood,ECF ECF, ICF

There are four factors that cause edema by either increasing filtration and/or decreasing reabsorption: 1. Increased ______ 2. Decreased _____ 3. Increased ______ (allows protein to get out of the blood into the interstitial spaces) 4. Lymphatic obstruction: when the lymph cannot return to the venous blood These factors are discussed in the following slides

capillary hydrostatic pressure capillary oncotic pressure capillary membrane permeability lymphatic obstruction

Hypovolemia: ____ in ECF and plasma volume • Symptoms of hypovolemia include: 1. Weight loss 2. Flattened neck veins 3. Weak pulses 4. Tachycardia (rapid heart rate to compensate for the low blood volume and pressure) 5. Decreased (or normal) blood pressure (due to decreased blood volume) 6. Postural hypotension (blood pressure drops upon standing; may cause loss of consciousness) 7. Decreased urine output and concentrated urine 8. Dry skin and mucous membranes 9. Thirst 10. In severe cases: hypovolemic shock

decrease

Percent TBW (relative to body weight) _____ with the amount of body fat - Reason: fat is hydrophobic (water-repelling), so people with ____ body fat have ____ TBW - People with more body fat are more susceptible to fluid imbalances and to dehydration because they have less TBW available - In general, this is true for gender (_____<____) and age (____<___)

decreases more, less females, males old, young

The body regulates water volume within a relatively narrow range although daily fluid intake may fluctuate widely • The primary sources of water ingestion are: 1. _____ 2. _____ 3. The water derived from _____ • The sources of water loss: 1. ____ excretion is the primary source 2. ____ 3. Insensible water loss: through _____ from skin and lungs • Disease states involving fever cause TBW to decrease (dehydration)

drinking eaitng oxidative metabolism renal stool vaporization

Accumulation of fluid in the interstitial space causes tissue swelling (edema) • Edema occurs when much more fluid moves out of the capillaries than back in • Thus, edema is caused by: 1. Increased ____ (more fluid moving out of the capillaries) 2. Decreased _____ (less fluid moving back into the capillaries) 3. Both of the above

filtration, reabsorption

• Forces favoring filtration: - capillary ____ pressure (blood pressure) - interstitial ____ pressure (water-pulling) • Forces favoring reabsorption: - plasma (capillary) ____ pressure (water- pulling) - Interstitial _____ pressure

hydrostatic oncotic oncotic hydrostatic

Hypervolemia: ______ in plasma volume (ECF) • Symptoms of hypervolemia include: 1. Increased body weight 2. Distended neck veins 3. Increased blood volume 4. Increased blood pressure 5. Increased urine output 6. Diluting of the plasma: • Decreased hematocrit • Decreased plasma concentration of proteins Q7 7. Edema: due to BP capillary hydrostatic pressure and capillary oncotic pressure (diluted plasma proteins) 8. In severe cases: pulmonary edema and heart failure

increase

TBW=ICF+ECF - Intracellular fluid (ICF): fluid ____(40%) - Extracellular fluid (ECF): fluid ______ (20%) • The extracellular fluid is divided into smaller compartments: 1. _____ fluid 2. _____ fluid 3. _____ 4. _____ fluid

inside cells outside of cells interstitial intravascular lymph transcellular

The cells of the body live in a fluid environment, bathed in the ____ fluid

interstitial

The distribution and movement of water and nutrients between the plasma in capillaries and the interstitial fluid is a result of the net force exerted by: Hydrostatic pressure: pushes water Osmotic pressure: pulls water • When referring to the plasma: it is called _____ pressure • Oncotic pressure is a type of osmotic pressure that is exerted by _____, which remain in the capillaries and exert the main pulling force

oncotic proteins

• In the capillaries, the ____ is somewhat greater than the _____ • Thus, not all the fluid returns to the blood, rather some of it remains in the interstitial space • The lymphatic system returns that extra fluid back into the blood by emptying into the subclavian veins

outflow, inflow

Hypovolemic shock: - A severe and acute metabolic disturbance caused by severe _____ of blood volume due to either dehydration or hemorrhage - As a result of blood loss or dehydration, the volume of blood returning to the heart (venous return) is decreased - This causes reduced stroke volume and cardiac output • Stroke volume: the amount of blood pumped by the heart with each beat • Cardiac output: (CO=SV*HR); the amount of blood pumped by the heart every minute - This results in inadequate tissue perfusion (amount of blood going to the tissues, including to the heart muscle itself) which could lead to circulatory arrest and death

reduction

• Electrolytes and other solutes are distributed throughout the intracellular and extracellular fluid • Note that the extracellular fluid contains a large amount of ____ and chloride and a small amount of _____, whereas the opposite is true of the intracellular fluid.

sodium, potassium

Any fluid in any compartment of the body exerts two types of forces: Hydrostatic pressure: pushing force Exerted by any fluid in a "container" on the container's walls Osmotic (oncotic) pressure: pulling force • Exerted by any fluid that has ___ dissolved in it • All body fluids are solutes (not pure water) • Water movement between two compartments: - Always involves four forces because: • Each compartment has 2 forces 1. Hydrostatic pressure 2. Osmotic pressure - The movement of water occurs in the direction of the strongest force (net force of all pressures)

solute

A fluid environment requires homeostasis, i.e., some variables must be maintained within a narrow range including: 1. Concentrations of glucose and electrolytes (Na+, K+, Ca++, Cl- ): affect the solute concentration of the blood • Osmolarity is the concentration of _____ per ____ of plasma (Osmol/L) • Osmolality is the concentration of ____ per ____ of plasma (Osmol/Kg; the preferred clinical term) Concentrations of hydrogen ions (pH value; acidity): affects enzyme function Temperature: affects enzyme function

solute, liter solute, Kg

Generalized edema is usually associated with: 1. _____ 2. _____ and puffiness 3. Tight-fitting cloths and shoes 4. Limited movement of the affected area

weight gain swelling