FLUID DISTRIBUTION AND EDEMA Flashcards
intracellular fluids
- 2/3 is water
whole vascular volume
- 5L
- 3L is plasma
- 40% RBC
total body weight
- 60% (60L) men
- 50% women more adipose tissue 5% breast
TBW
- 60L
40% intracellular fluid
20% extracellular fluid 2/3 is interstitial (in bet.cells)
ICF vs ECF
- fluid goes from ICF(6) to ECF(12) due to greater concentration
osmotic pressure/ osmolar pressure
- lift draw of water to the area of higher concentration
- balancing out electrical forces
hydrostatic pressure
- arteriolar
electrical pressure
- K+ and Na+ cation ions repel each other
2x Na concentration
- index for EXTRACELLULAR OSMOLARITY
ECF osmolarity INCREASES
- cell SHRINK
- sodium concentration with in the cell is INCREASING
- HYPEROSMOLAR
ECF osmolarity DECREASES
- cell SWELL
- cells becomes dehydrated
STEADY STATE SITUATION
- intracellular=extracellular concentration of water
osmolar pressure
- is the SODIUM
WATER PUT ON A BLOOD
- cells swell and burst patient dies
- D5W is used to prevent this
ICF
2/3 TBW
ECF
1/3 interstitial
TBW men
60L
TBW women
50L
blood minus cell
- plasma
serum
- clotting factors removed(post clotted blood)
plasma
- has the clotting factors
- physiologic
volume
- widening convergence and expansion
concentration
- vertical increase(hyperosmolar) and decrease(hypo osmolar)
loss of isotonic fluid (hemorrhage loss of intracellular fluid as RBC volume not changing concentration), isotonic urine, diarrhea or vomiting
- losing only plasma
- extracellular fluid loss
- volume
- no movement of fluids in either direction because ICF and ECF has the same 300 mosm concentration
- DECREASE ECF VOLUME
- NO CHANGE IN BODY OSMOLARITY AND ICF VOLUME
loss of hypotonic fluid sweating, hypotonic urine, diabetes insipidus, dehydration, ALCOHOLISM (nephrogenic DI) inhibit ADH loss of free water
- salt retention increase osmolality ECF
- increasing concentration decreasing volume
- effect on ICF fluid move out of the cells to compensate hence ICF volume is decreasing
- DECREASE IN ECF AND ICF VOLUME
- INCREASE IN BODY OSMOLARITY
salt tablets
- increase osmolality
- dehydrate the cells
- ECF concentration will increase
tap water or distilled water has the lowest sodium content, IVF
- ECF osmolality decreases
- ICF concentration decrease
patient hypotensive, sepsis, GI bleeding, burns volume loss
- you want the volume in the vascular space
- normal saline IVF is used
major blood volume loss
- IVF used normal saline .9 or lactated ringer isotonic solution it will expand ECF
infusion of isotonic saline normal saline, 0.9%, ringers lactate
- no osmotic draw
- INCREASE ECF VOLUME
- NO CHANGE IN BODY OSMOLARITY AND ECF VOLUME
hypertonic saline in hge, mannitol
- it will cause seizures because of the rises in osmolality
- expand plasma volume increase
- INCREASE ECF VOLUME AND BODY OSMOLARITY
- DECREASE ICF VOLUME
high sodium affects the
- CNS seizures
primary adrenal insufficiency
- loss of aldosterone
- function of aldosterone retain sodium excrete hydrogen ions and potassium
- decrease osmolality due to loss of sodium, chloride and water cause decrease in volume(hypo osmolality)
- decrease blood pressure
HYPOTONIC SALINE, water intoxication
- INCREASE ECF AND ICF VOLUME
- DECREASE BODY OSMOLARITY
- dehydrate the cells
arteriolar constriction and dilation(has circular muscles) of the afferent and efferent
- hydrostatic forces(water pressure)
- hydrostatic pressure constant in the the afferent and efferent is maintained by
GFR
- 20% is filtered
efferent and afferent arteriole
- pressure is the same hydrostatic pressure
constrict and dilate
- arterioles
cannot constrict and dilate
- venules
- large arteries(AORTA, femoral artery, brachial artery)
- capillaries
- veins
after load
- arteriolar resistance
capillaries(very thin)
- highly permeable because they cannot constrict and dilate
- can diffuse in and out
- protein can leak out in the interstitial
oncotic pressure
- is protein
hydrostatic pressure
- capillary
- push fluid out in the arteriolar capillary (FILTRATION)
- if it is in the INTERSTITIAL FLUID(reabsorption), forces push IN
oncotic pressure
- interstitium
- pull OUT the fluid into the interstitial fluid capillary (FILTRATION)
- if it is in the capillaries (reabsorption), forces pulls IN
Pc plus ^^if 25 + 1
- 26
Pif plus ^^c 20 + 2
- 22
rate fo flow is
- 26 minus 22 = 4mm Hg
decrease hydrostatic pressure in the interstitial FLUID/space
- will INCREASE THE FORCE OF FILTRATION
tracers
- dye injected IV 300mg
- trace divided by blood concentration 0.05mg/ml= volume of distribution
- 300mg/0.05mg/ml=6000ml
inulin
- is filtered but not reabsorb nor secreted
the lower the hct
- the higher the plasma
the higher the hct
- the lower the plasma
ECF
- saline and mannitol pass the cellular membrane will go to interstitial space
higher water concentration
- low osmolality
low water concentration
- high osmolality
urea changes the osmolality equally
- no net movement of water
mannitol can
- increase osmolality
EDEMA
- INCREASE hydrostatic pressure with in the capillary it pushes fluid in the interstitial space
- STARLING FORCE
- retention of sodium and water in the kidney
- CHF no intravascular volume, afferent constricts, JG constricts, start making renin, angiotensin, angiotensin II aldosterone causing hypotension
non pitting edema (lymphedema)
- lymphedema
- does not respond to diuretics
- develops after removal of systemic tissue (e.g. removal of axillary lymph node in breast cancer)/altered normal lymphatic drainage/configuration
pitting edema (MOST COMMON)
- RESPOND TO DIURETICS
- common causes include nephrotic syndrome,CHF, cirrhosis
retention of sodium and water by the kidney causing decrease renal perfusion
- cirrhosis
- nephrotic
- CHF
- pericarditis
pulmonary edema (CHF)
- anything that blocks the return of fluid in the LEFT ATRIUM from pulmonary veins then drains into the left ventricle
- back up of fluid due to left ventricular dysfunction at the pulmonary capillary system
- increase capillary pressure causing pulmonary edema
- LEFT VENTRICLE ==>LEFT ATRIUM=>PULMONARY VEIN=>PULMONARY CAPILLARIES==> INCREASE HYDROSTATIC PRESSURE==> puts fluid in the interstitial space and in the alveoli= causing pulmonary edema(FLUID BACK UP)
- HYDROSTATIC PRESSURE> ONCOTIC PRESSURE
- decrease in albumin
normal person
- no protein in the alveoli
- alveolus should be empty kept by tight junctions( in drowning alveolus has water)
alveolar proteinosis
- protein in the alveoli
- with oncotic pressure in the alveoli
DIURETICS ARE GIVEN
- to DECREASE hydrostatic pressure in the pulmonary capillaries
most common form of pulmonary edema
- CARDIOGENIC PULMONARY EDEMA
- lower plasma proteins predispose to cardiogenic edema
- increase left atrial pressure, venous return, capillary pressure and filtration
- MOST COMMON SIGN DYSPNEA
- caused by low plasma proteins
- pulmonary wedge pressure (LEFT ATRIAL PRESSURE)confirms the diagnosis IS INCREASE
- sitting upright relieves the pressure
- treatment goal: reduce LEFT ATRIAL PRESSURE diuretics DECREASES HYDROSTATIC PRESSURE
DIURETICS
- empty the lungs
non cardiogenic edema( FRIED LUNGS)
- due to direct injury of the alveolar epithelium
- severe lung injury (ARDS)
- MOST COMMON CAUSE: GASTRIC ASPIRATION AND SEPSIS
- presence of protein containing fluid the the alveoli inactivates the surfactant
- NO HYDROSTATIC PRESSURE INVOLVED
- ARDS direct damage the capillaries, BURNS, ATELECTASIS, amniotic fluid embolus, DIC
lymphatics
- cleans the lungs by taking all the proteins
