Q | Answer |
What are the 4 main causes of edema? | 1) Inc. Capillary Plasma hydrostatic pressure 2) Dec. Capillary Plasma oncotic pressure 3) Inc. Capillary Plasma permeability 4) Lymphatic Obstruction |
What is Edema? | Fluid accumulation in ITF |
What are the names of the two compartments body water exists in? | Extracelluar(ECF) and Intracellular (ICF) |
Total Body weight percentage for males and breakdown into IFC and ECF? | 60% of body water ( 40% ICF and 20% ECF) |
What regulate the movement of water between ICF and ECF? | Osmosis |
If you are obese will you have more or less TBW? Lean? | Less. More will occur if you are leaner. |
What are the two categories of ECF? | 1) interstitial 2) intravasular |
What is tonicity? | osmotic pressure of a solution relative to plasma |
What are two other names for Osmotic pressure? | Solute Concentration, Oncotic Pressure |
What does it mean if a solution is isotonic? | equivalent solute concentrations S/L<1 |
What does it mean if a solution is hypotonic? | less concentrated S/L<1 |
What does it mean if a solution is hypertonic? | more concentrated S/L>1 |
Molarity | solute concentration expressed as mass per volume. 1M=mass(gram MW(6x10^23 molecules)/Volume (liter)) |
What is osmolar concentration? | osmotically-effective concentration |
Osmolarity | # of osmoles per L solvent |
Osmolality | # of osmoles per kg solvent |
What is the primary cation in the ECF? | Na+ |
What is the primary cation in the ICF? | K+ |
What is the primary anion in the ECF? | Cl- |
What is an electrolyte? | mineral that carries electrical charge |
The anion and cation are _____ in the ECF and the ICF. | Electrically neutral |
Where does Oncotic and Hydrostatic pressure normally occur? | The Capillary |
Osmotic Pressure does what? | pull in |
Hydrostatic Pressure does what? | push out |
What do Osmotic and Hydrostatic Pressures do? | Control movement of water, nutrients and metabolic wastes between A) capillary plasma and B) interstitial fluid (ITF) |
What is net filtration? | balance of forces that favor vs oppose filtration |
Which two pressures are favoring net filtration? | CP Hydrostatic and ITF oncotic pressures |
Which two pressures are opposing net filtration? | CP Oncotic and ITF hydrostatic pressures |
What end of the capillary does filtration and which end does reabsorption? | Filtration: arterial
Reabsorption: venous |
Example # of Mercury for a net filtration pressure ( given in the chart in the slides) of the arterial end of the capillary | +10 mm Hg(subtract the net hydrostatic pressure and net oncotic pressure) |
Example # of Mercury for a net filtration pressure ( given in the chart in the slides) of the venous end of the capillary | -8 mm Hg ( subtract the net hydrostatic pressure and net oncotic pressure) |
What is the breakdown of the Net Hydrostatic Pressure in the arterial end of the capillary? | Cap. Hydrostatic pressure= 37 mm Hg
Interstitial fluid hydrostatic pressure = 2 mm Hg
Net Hydrostatic Pressure= 35 mm Hg |
What is the breakdown of the Net Oncotic Pressure in the arterial end of the capillary? | Cap. Oncotic Pressure = 25 mm Hg
Interstitial fluid oncotic pressure = 0 mm Hg
Net oncotic Pressure= 25 mm Hg |
What is the breakdown of the Net Hydrostatic Pressure in the venous end of the capillary? | Cap. Hydrostatic Pressure=20 mm Hg
Interstitial fluid hydrostatic pressure= 3 mm Hg
Net filtration pressure= 17 mm Hg |
What is the breakdown of the Net Oncotic Pressure in the venous end of the capillary? | Cap. Oncotic pressure= 25 mm Hg
Interstital fluid oncotic pressure= 0 mm Hg
Net Oncotic Pressure= 25 mm Hg |
What causes Increased hydrostatic pressure? | venous obstruction, salt and water retention, due to congestive heart or renal failure |
What causes decreased plasma albumin levels? | liver disease, protein malnutrition, hemorrhage, burns |
What causes increased Capillary plasma permeability? | inflammation/ immune responses |
What causes lymph blockage( Lymphedema)? | infection, surgery |
Fluid movement into tissue causes what specifically? | Increased Na and water retention--> edema |
What does lymph obstruction specifically cause? | Decreased absorption of interstitial fluid--> edema |
Loss of plasma proteins form increased capillary permeability causes what? | Increased tissue oncotic pressure --> edema |
What are the two different types of Edema? | Localized and Generalized |
What is dependent edema(pitting edema)? | type of generalized edema characterized by changes with posture( feet and legs while standing; buttocks while lying down) |
What are signs of dependent edema? | weight gain, swelling, puffiness, limited movement of affected area. |
What are some things that impact dependent edema? | decreased capillary flow and increased diffusion distance impedes wound healing; edema of specific organs can be life-threatening ( like the heart) |
What are some treatments for dependent edema? | symptomatic until underlying disorder is corrected; support measures include elevating affected limb , restriction of salt intake, administration of diuretics |
What is Water Balance maintained by? | anti-diuretic hormone (ADH) -physiological/ endocrine and thirst - behavioral |
The desire to drink water ( thirst) occurs when _____. | 1) fluid volume loss equals 2% of body water e.i. hypovolemia 2) hyperosmolality occurs |
What is ADH? | Secretion by the posterior pituitary gland. |
What is ADH stimulated by? What does it do? | The same factors as water( hypovolemia or hyperosmolality). It acts to enhance water reabsorption in kidney, thereby increasing urine concentration. |
What stimulates thirst and AHD? | CNS osmoreceptors |
What specifically stimulates AHD? | Peripheral baroreceptors and volume sensitive receptors |
Where are peripheral baroreceptors located? | aorta, carotid sinus, and pulmonary vessels |
Where are the volume sensitive receptors located? | atria and thoracic vessels |
Decreased circulating fluid volume or increased plasma osmolality has what affect on the body? | increases thirst and increased ADH secretion. |
Increasing ADH secretion does what? Which in turn does what? | decreases water excretion which increases water retention |
Increased water retention has what effect on the body? | It increases circulating fluid volume and decreases plasma osmolarity. These in turn lower thirst and ADH. |
What does the brain osmoreceptors detect? | lowered plasma volume and increase plasma osmolality |
What does the volume receptors detect? | lowered plasma volume |
Osmoreceptors and volume receptors pass on their detected levels of dec. plasma volume and inc. plasma osmolality to ______. | Hypothalamus |
What is the Hypothalamic-Posterior Pituitary Axis? | The Hypothalamus transfers information to pars nervosa of posterior pituitary when then acts on ADH which causes renal water retention |
What regulates Na+ balance? | Kidneys |
What is Aldosterone? | a mineralocorticoid steroid hormone secreted by the adrenal cortex. |
What does Aldosterone do? | acts on the kidneys to increase urinary Na+ reabsorption/ K+ excretion( opposite actions on Na versus K) |
How is Aldosterone regulated? | By the Renin- angiostensin cascade |
What happens when blood volume is low? | The kidney secretes the enzyme renin which catalyzes the production of angiotensin 1 (ANG-1). ANG-I is cleaved to ANG-II by angiotensin- converting enzyme in the lungs. |
What does Angiotensin II do? | 1) stimulates aldosterone secretion from the adrenal cortex 2) causes vasoconstriction in the blood vessels |
Anti- Natriuretic Peptides are produced by ______. | The heart, brain, and kidney |
What do Anti-Natriuretic Peptides do? | They act on the kidney to increase Na+ excretion and K+ reabsorption to decrease blood pressure. ( opposite actions to aldosterone on Na+,K) |
What produces Angiotensinogen? | Liver |
What all can increase Renin production from the kidney? | Dec. Renal perfusion, Dec. Serum Na+, Inc. Urine Na+, Dec. ECF, Dec. Blood Pressure |