patho fluids and electrolytes

Topics: Blood, Blood pressure, Carbon dioxide Pages: 23 (4098 words) Published: February 24, 2014
Chapter 6 Study Guide
Fluids, Electrolytes, and Acid-Base balance

Compartmental Distribution of Body Fluids
2/3 of the body’s water is contained in the ICF, the remaining 1/3 is in the ECF ICF fluid volume is regulated by proteins and other non-diffusible organic compounds in cells

Interstitial fluids (IF) act as a transport vehicle for gasses, nutrients, wastes, and other materials 14%-16% of body weight
Reservoir for maintenance of vascular volume; used during hemorrhage

Plasma (vascular) compartment = blood
4%-5% of body weight

Tissue gel fills in tissue spaces and aids in the even distribution of interstitial spaces Acts as a sort of sponge

Transcellular compartment- contains cerebrospinal fluid; fluid in peritoneal, pleural, and pericardial cavities; fluid in joint cavities; aqueous and vitreous humor Normally about 1% of ECF
Referred to as a third space when it becomes considerably enlarged

Edema

Edema- palpable swelling produced by expansion of the interstitial fluid volume when fluid filtration out of capillaries is greater than the reabsoprtion of fluids back into capillaries

Physiologic mechanisms responsible for Edema:
1) increased capillary filtration pressure- increased movement of vascular fluid into interstitial spaces elevated blood pressure (hypertension)
relaxation of pre-capillary sphincters (more blood in capillaries) increased vascular volume
2) Decreased capillary colloidal osmotic pressure- less fluid is reabsorbed by capillaries Decreased liver function, inadequate production of plasma proteins Abnormal loss of protein by the kidneys

Starvation, malnutrition, burn injuries
3) increased capillary permeability- proteins escape capillaries into interstitial fluids inflammatory and immune responses
trauma and burn injuries
4) obstruction of lymph flow- lymph normally moves osmotically active particles that are not reabsorbed by capillaries back into the circulatory system lymphedema- edema caused by impaired lymph flow

Peripheral edema- due to failure of the right side of the heart Pulmonary edema- due to failure of the left side of the heart

Manifestations:
swelling that may or may not impair function
increases distance for diffusion of nutrients
more susceptibility to injury and ischemia (restriction of blood supply); pH drop due to CO2 buildup compression of blood vessels

Assessment:
daily weight, visual assessment
measurement of affected part
application of finger pressure (indicates pitting edema)
urine output

Treatment:
maintenance of life when vital structures are involved
correcting or controlling the cause
prevention of tissue injury
diuretic therapy to get rid of excess fluid
lower extremities: elevation and elastic support hose which resist movement of fluids out of capillaries

Tonicity

Tonicity- the tension that the effective osmotic pressure of a solution with impermeable solutes exerts on cell size due to water movement across the cell membrane clinical importance of isotonic solutions- can be infused into blood without upsetting the osmotic equilibrium between ICF and ECF

Cells in hypotonic solution:
cellular swelling as water moves into cell

Cells in Hypertonic solution:
cell shrinks as water moves out of cell

Diffusion vs. Osmosis

Diffusion- movement of charged or uncharged particles along a concentration gradient (usually fat-soluble particles) Particles move to areas of lower concentration of solutes
Water-soluble molecules move via facilitated diffusion

Osmosis- movement of water across a semi-permeable membrane (permeable to water but impermeable to most solutes) Water diffuses down concentration gradient to the side with the higher concentration of solutes

Osmole- measures osmotic activity exerted by non-diffusible particles in pulling water from one side of the membrane to the other Tendency of water to move toward higher concentration of...
Continue Reading

Please join StudyMode to read the full document

You May Also Find These Documents Helpful

  • Fluids and Electrolytes Essay
  • Fluid and Electrolytes Essay
  • Fluid and Electrolytes Essay
  • Fluid & Electrolyte Imbalances Essay
  • Fluid and Electrolyte Study Guide Essay
  • Patho Essay
  • Patho Essay
  • Water and Electrolytes Essay

Become a StudyMode Member

Sign Up - It's Free