body fluid balance Flashcards
1- For adult 70kg male, as % of body weight
Water (Fluid)———– — %
Solids——————– — %
Fats, Carbohydrates, Proteins, Minerals
-Water content varies inversely with – content
2- Females: Water content = — % of body weight
- % of body water also — with age
3- Newborns: Water content = – % of body weight
60%
40%
fat
50%
decreases
75%
- Besides water, both ECF and ICF consist mainly of — .
- These fluids contain only small quantities of — , — , —
- In both fluid compartments, the electrolytes are almost —
dissociated they exist as —
elctrolytes
non elcntrolytes amino acids glucose
completely
free ions ( checj slide 7 pls)
In ECF:
- — is the main positively charged ion.
- — (and — ) are the main negatively charged ions.
- There is very little – in the ECF.
In ICF:
- — is the main positively charged ion.
- — and — are the main negatively charged ions.
- There is very little — and– in the ICF.
question - most abundant present in :
Cation in the plasma: –
Anion in the intracellular fluid : –
Anion in the interstitial fluid: –
na+
cl- and HCO3-
k+
k+
PO43- and proteins
na+ and cl-
na+
po43-
cl-
- The compositions of ECF and ICF are normally maintained —
- Constancy of ECF composition critical for –
- Composition of the ECF maintained by —
- Cellular function requires composition of ICF be — .
–> — has an important influence on cellular reactions.
—> Constancy of ICF is mainly maintained by – which the cells possess.
constant
cell fucntion
homeostasis
constant
ionic stength
mechanims
1- ECF composition:
- Everyday activities of the body changes the composition of — and the — i.e. the ECF
-This tendency is — by control mechanisms in the body which results in ECF composition remaining —
-The process of maintaining the ECF constant is called —
2- ECF composition , glucose homeostasis and -ve feedback:
- [glucose] in plasma between meals = — mmol/L
- If [glucose] in plasma increases (e.g. after a meal), — secretion of the hormone — occurs
- Insulin — [glucose] in plasma
- If [glucose] in plasma decreases, the opposite occurs
- Regulation of [glucose] described as called “ —”
-This is the principle method in body for maintaining — of ECF
-Similar mechanisms operate for other variables homeostatic maintenance of blood pressure, temperature, blood pH
blood plasma and interstiial fluid
offset
constant
homeostasis
4-5
increases
insulin
decreases
-ve feedback
constancy
1- ICF composition
- The — separates intracellular fluid from extracellular fluid
- Highly — membrane
-Cell membranes are highly — to –
- — permeable to small, but not large ions or small solutes
2- ICF and NA/K transporter pump :
- K+ is pumped back — cells and Na+ is pumped back — of cells by the Na/K pump , Consequently, ICF ionic content remains —
- Approx – times volume of water in a cell crosses PM every –
- Cells normally do not experience any – or –
- Amount that diffuses in the two directions is – .
-If concentration difference for water develops across membrane, — of water does occur
- Process of net movement of water caused by — in water is called —
- Water will move — down its own concentration gradient from area of — water concentration ( — solute concentration) to area of – water concentration ( — solute concentration)
-Solutions are always referred to in terms of concentration of — , water moves by — to the area of— solute concentration
cell membranr
selective
permeable to water
selctively
into
out
constant
100 times
second
swelling or shirnkage
balanced
net movement
concentration difference
osmiosis
passively
high
lower
lower
high
solute
osmosis
higher
osmosis:
1- – ions and — ions in solution
2- solute n solvent ions will diffuse across — barrier from — to — concentration until – is established
3- if the solute ions are larger than the holes in the barrier but the solvent ions are smaller than the holes this is termed as —
4- of we start w the solvent only and place a high solute concntration on one side of the semi permeable membrane only we see an enterseting difference
- in osmosis the — passes through — membrane to — the – solute concnetration on the other side
solvent and solute
permeable barrier
high to low
semi permebale membrane
solvent
semi permeable
dilute
high
- Osmotic movement of water will only occur if the osmotic pressure of the – differs from that of the –
- The osmotic pressure of body fluids is a measure of the – for – to move – that solution because of its relative concentration of non-penetrating – and –
- Osmotic pressure is an— measurement of the – and — concentrations of a solution.
- The higher the osmotic pressure of a solution, the — the water concentration and the — the solute concentration of the solution
-Normally, the osmotic pressure of ECF is– to that of ICF. - – and its — antions account for the vast majority of the ECF’s osmotic activity.
-In contrast, — and its accompanying — anions are responsible for the ICF’s osmotic activity.
-Because these values are normally – , no net movement of water occurs into or out of cells and cell volumes normally remain constant.
ECF and ICF
tendancy
water
into
solutes and water
indirect
water and solute
lower
higher
similar
sodium and attendant anions
potassium and intracellular anios
equal
the relationship between moles to osmoles in body fluids :
-The osmotic pressure exerted by particles in a solution is determined by the number of the — per unit— of – not by the – of the particles.
-To express the concentration of a solution in terms of number of particles, the unit called the — is used.
-1 osmole (osm) is equal to – mole (mol) of– particles
-Osmole refers to number of osmotically – particles in a solution rather than —
- Solution of 1 mole of glucose/litre has an osmolar concentration of – osm/L
- Solution of 1 mole of NaCl/litre has an osmolar concentration of – osm/L
- Solution of 1 mole of Na2SO4/litre has an osmolar concentration of – osm/L
- Osmole too – a unit to express osmotic activity of solutes in body fluids – milliosmole used (mOsm) – 1/1000th osmole
particles
volume of fluid
mass
osmole
1 mole of solute
active
molar concnetration
1
2
3
too large
The osmotically effective concentration of a solution is expressed as the – or — of the solution.
The term osmolarity is used when the osmotically effective concentration of a solution is expressed in – solution (— )
The term osmolaity is used when the osmotically effective concentration of a solution is expressed in — solvent (— )
For dilute solutions such as body fluids, osmolarity – osmolality
- The exact osmolarity of body fluids is
— ± – mosmol/L ..
- The main determinants of ECF osmolarity are — and —
- The main determinants of ICF osmolarity are — and –
osmolaity or osmolarity
osmoles/liter SOLUTION ( Osmol/L)
osmoles/kg SOLVENT ( osmol/kg)
equals
283 ±11
na+ + cl-
K+and PO43-
( check question 28,29 sooo important )
control of body fluids osmolairty:
- — of water balance is critical for regulating body fluid osmolarity
- — of water balance are associated with changes in body fluid osmolairty
-Changes in body fluid osmolarity result in — movement of water into or out of cells
- Water moves from a solution of — osmolarity to one of – osmolarity until the osmolarity in the two solutions is–
control
disturbances
osmotic
low
higher
equal
diabetes mellitus type 1 ,2 :
-Results from absolute or functional deficiency of circulating —
- Characterized by —
-Glucose is an osmotically — molecule
- Increased osmolarity of –
- Water shifted from – to –
- Intracellular –
- Urinary glucose excretion (—)
- — excretion of glucose from kidneys:
- >Osmotic diuresis (— )
-> —
- — , intracellular and extracellular — and increased – are all classic symptoms of diabetes
insulin
hypergycemia
active
ECF
ICF to ECF
dehydration
Glycosuria
increased
polyuria
dehydration
polyuria , dehyration , thirst
1- control of bodt fluids osmolarity:
1- Sources of water input
- Drinking —
- Eating – foods
- — produced water
2- Sources of water output
- insensible loss as – that is not readily measured. Consists mostly of water lost via evaporation through non-sweating skin (two thirds) or respiratory tract (one third).
Varies with gestational age
- sensible loss as — , — , — excretion – most NB
2- dehydration/underhydration:
- Insufficient – Intake
- Desert Travel
- Difficulty in–
- Excessive – loss
- Heavy sweating, vomiting, diahorrea
Infectious disease (Cholera)
- Diabetes —
drinking liquids
solids
metabolically
water loss
sweat faces and urine
h20
swallowing
h20
insipidus
1- diabetes insipidus:
- Characterised by deficiency in — (Antidiuretic Hormone/ – )
- Normal function reduce – output so enhances water — in body
- In its absence patients can produce up to 20 L very dilute urine daily (Normal average 1.5 L)
2- effects of dehydration/underhydration:
- Water content of plasma and interstitial fluid (the entire ECF) — causing — concentration of ECF –> — of ECF — ( — of the ECF) —> Water leaves all cells by osmosis through the cell membranes —> Osmolarity of ICF — —> Disruption of — function
dehydration symptoms:
- Symptoms are mainly — as water loss from brain cells leads to — of cells
Mild cases :
Dry skin & tongue, sunken eyeballs
Moderate cases :
Mental confusion, irrationality
More severe:
Delirium, convulsions, coma
Non neural symptoms : — disturbances
vary from slight — of blood pressure to circulatory — and —
vasopressin
adh
urinary
conservation
decreases
increases
osmolarity
increases
hypertoiticty
increases
cellular
neurlogical
shrinkage
ciruclatory disturbances
lowerinf
shocj
death
1- water retention/ overhydration:
- Any free surplus H2O is promptly— so overhydration generally does not occur
- Patients with renal failure:
Cannot excrete — and become — upon consuming more — than —
- — body mass infants
- Marathon runners who drink only water
- Over- — (Overexertion/MDMA-Ecstasy)
-Syndrome of Inappropriate —
2- effects of water rentention/ overhydration:
- Excess water distributes throughout the plasma & interstitial fluid (the entire ECF) and dilutes the —
- Osmolarity of ECF — ( — of ECF)
- Water moves by osmosis through cell membranes – all cells
- Osmolarity of ICF –
- Disruption of — function
3- symptoms of water retention/ overhydration:
- Symptoms related mainly to water entry into brain cells & — of brain cells leading to a — in cell fluid osmolarity in these cells
- This in turn leads to altered — function
Confusion, lethargy, headache, dizziness, vomiting severe cases coma & death
-Non neural symptoms include
Weakness swelling of muscle cells
Circulatory disturbances
expansion of plasma volume
excreted
dilute urine
hypotonic
more h20 than solutes
low
overheating
Vasopressin/ADH Secretion (SIADH)
ECF
decreases
hypotonicity
into
decreases
cellular
swelling
decrease
neurlogical
Tonicity is a measure of the— gradient of – solutions separated by a — membrane.
- Like osmotic pressure, tonicity is influenced only by — that cannot cross the plasma membrane, as only these exert an osmotic pressure.
- Solutes able to – cross the plasma membrane do not affect tonicity.
- It is commonly used when describing the response of cells immersed in an — solution.
–> whether the cell remains the same size, swells or shrinks when the solution surrounds the cell.
1- hypertonic solution : solution has an osmotically effective concentration which is — than that of ECF.
2- isotonic solution: has an osmotically effective concentration which is the — as that of the ECF3-
hypotnic solution: has an osmotically effective concentration which is – than that of plasma
osmitoic pressure gardient
2 solutions
semipermeable
solutes
freely
external
greater ( basically h20 leaves)
same
less ( h20 enters )
check slide 42 so importsnt
intravenous solutions are — prepared solutions given to the patient.
Administered by — /— directly into the –
Tailored to body’s needs and used to replace lost fluid and/or aid in the delivery of IV medications
e.g. administer an antibiotic intravenously
these can be :
1- colloid solutions which are – to – the edmema
2- crystalloid solutions which can be :
- — : 0.9 % NaCl
To replace salt loss
5% Dextrose in water (D5W)
To maintain water balance
- — : 0.45 % NaCl
To correct
hyperosmolar
state
- — : 1%,3%,7%,7.5% & 10% NaCl
10% Dextrose in water
To correct overhydration
To expand plasma volume
3- blood products
chemically
injfection/infusion
blood
hypertonic
reduce
isotoni
hypotonic
hyperotinic
cyrstalloids :
— solutions
Fluids consisting of sterile – & — solutions
Both water & electrolytes will cross a – membrane into the — space and achieve equilibrium in — hours.
Crystalloids are the mainstay of — therapy and are classified according to their —
crystalloids and isotonic saline:
Almost every patient undergoing surgery will be given an — drip of – saline
Routinely used for i.v. rehydration or administration of drugs to patients
Isotonic saline could be administered to patients with low — volume ( — )
It will distribute throughout the ECF, — ECF volume without altering ECF —
clear
sterile water and elctrolyte
semi permeable membrane
interstitial space
2-3 hours
iv therpay
tonicity
iv
isotonic
ECF
dehydration
increasing
osmolarity
overhydration
example:
e.g. 3% or 5% NaCl
To whom might it be administered?
Patients whose plasma osmolarity is — , and as a result water has moved into cells (—).
example:
e.g. 0.45% NaCl
To whom might it be administered?
Patients whose body fluids are—
0.45% saline is generally given to patients with — who need to be rehydrated but do not need additional sodium
low
overhydration
hyperosmotic
renal disease
colloids:
— molecular weight solutions (MW > — daltons)
e.g. albumin/dextran/mannitol solutions
do NOT — cross semi-permeable membranes
Because of their high osmolarity they are important in — dynamics
which can effectively exert an — across the wall of— .
Initially they stay almost entirely in the intravascular space for longer periods of time (— h) than crystalloids
Reduces abnormal— of fluid in interstitial compartment (— )
–> they draw fluid from interstitial and intracellular compartments into— compartments.
high
30,000
readily
capillary fluids
osmiotic force
capillaries
3-6
accumulation
edema
vasuclar
