OXYGEN, FLUID BALANCE AND ELECTROLYTES EXAM
ALL QUESTIONS AND CORRECT DETAILED ANSWERS
WITH RATIONALES|AGRADE
Compare body water to total weight in infants and adults. - ANSWER: The total body
water is about 80% of body weight at birth, gradually decreasing with age to 60-65 %
in adults.
Identify patients more susceptible to fluid imbalance. - ANSWER: patients with
RENAL DISEASE, because these patients kidney's fail to maintain fluid, electrolyte,
and acid-base balance. Decreased blood flow to the kidney's due to
CARDIOVASCULAR DISEASE stimulates RAAS causing water retention. DM, CANCER,
and COPD may affect acid-base imbalance.
Discuss the two basic fluid compartments - ANSWER: INTRACELLULAR FLUID: water
found within the body's cells (2/3 total body fluid) EXTRACELLULAR FLUID: plasma
(within the vasculature) and interstitial fluid (where edema occurs, found in the area
surrounding the cells).
Define electrolytes. - ANSWER: charged particles capable of conducting electricity.
Electrolytes affect the amount of water in your body, the acidity of your blood (pH),
your muscle function, and other important processes. You lose electrolytes when
you sweat. You must replace them by drinking fluids.
Describe cations. - ANSWER: the number of ions carrying a positive charge. NA+, K,
CA+, and MG+.
Describe anions. - ANSWER: the number of ions carrying a negative charge. CL-,
bicarbonate, phosphate, and sulfate.
3. Identify the major electrolytes in ICF and ECF.
a. Potassium
b. Sodium - ANSWER: POTASSIUM: regulates-renal excretion, aldosterone increases
K excretion, mvmt into and out of cells, insulin helps move K into cells; tissue
damage and acidosis shift K out of cells into ECF SODIUM: regulates-renal absorption
or excretion, aldosterone increases Na+ reabsorption in collecting duct of nephrons
Discuss the four major mechanisms of fluid and electrolyte movement. - ANSWER:
DIFFUSION: occurs when two solutes of different concentrations are separated by a
semipermeable membrane. molecules move from higher to lower concentrations.
OSMOSIS: water moves across cell membranes from less con. sol. to more con. sol.
(capillary membrane) FILTRATION: fluids and solutes move together across a
membrane from high pressure to low pressure areas. ACTIVE TRANSPORT: moves
and holds sodium and potassium against their diffusion gradients.
, Compare hydrostatic and osmotic pressure. - ANSWER: HYDROSTATIC PRESSURE: the
pressure exerted by a fluid within a closed system on the walls of the container in
which it is contained.
OSMOTIC PRESSURE: the power of a solution to pull water across a semipermeable
membrane. The solution with a higher concentration exerts a higher osmotic
pressure.
Define osmolality. - ANSWER: the concentration of solutes in the body fluids.
Determined by the total solute concentration within a fluid compartment and is
measured as parts of solute/kg of water.
2. Compare the following
a. isotonic
b. hypertonic
c. hypotonic solutions - ANSWER: ISOTONIC- has same osmolality as ECF...(0.9%
Na+Cl) HYPERTONIC- has a higher osmolality than ECF...(3% Na+Cl) HYPOTONIC-
have a lower osmolality than ECF...(0.45Na+Cl)
Discuss the role of the following in the control of fluid and electrolyte balance. Blood
pressure - ANSWER: If blood pressure/blood flow to the kidney's decreases, renin is
released, which causes the conversion of angiotensin to angiotensin I to angiotensin
II which acts directly on the nephrons of the kidney's and promotes sodium and
water retention. Also it stimulates the release of aldosterone which promotes
sodium retention in the distal nephron. so ultimately BP is increased as well as renal
perfusion.
Colloids - ANSWER: plasma proteins are colloids and exert a pressure called colloid
osmotic pressure. This holds the water in the plasma and when necessary pulls water
from the interstitial space into the vascular compartment. This helps to maintain
vascular volume.
Kidneys - ANSWER: excrete hydrogen ions and retain bicarbonate. kidney's regulate
the volume and osmolality of ECF by REGULATING WATER AND ELECTROLYTE
EXCRETION.
ADH - ANSWER: synthesized in the anterior portion of the hypothalamus and acts on
the collecting ducts of the nephrons by making the collecting ducts become more
permeable to water ALLOWING MORE WATER TO BE ABSORBED INTO THE BLOOD.
blood volume, stress, temperature, pain and opiates affect release of ADH.
Aldosterone - ANSWER: promotes SODIUM RETENTION in the distal nephron,
INCREASING THE BLOOD VOLUME.
Parathyroid hormone [S] - ANSWER: increases reabsorption of phosphate (major
anion in ICF), causing more to be excreted through urine and increases the amount
of calcium in circulation
ALL QUESTIONS AND CORRECT DETAILED ANSWERS
WITH RATIONALES|AGRADE
Compare body water to total weight in infants and adults. - ANSWER: The total body
water is about 80% of body weight at birth, gradually decreasing with age to 60-65 %
in adults.
Identify patients more susceptible to fluid imbalance. - ANSWER: patients with
RENAL DISEASE, because these patients kidney's fail to maintain fluid, electrolyte,
and acid-base balance. Decreased blood flow to the kidney's due to
CARDIOVASCULAR DISEASE stimulates RAAS causing water retention. DM, CANCER,
and COPD may affect acid-base imbalance.
Discuss the two basic fluid compartments - ANSWER: INTRACELLULAR FLUID: water
found within the body's cells (2/3 total body fluid) EXTRACELLULAR FLUID: plasma
(within the vasculature) and interstitial fluid (where edema occurs, found in the area
surrounding the cells).
Define electrolytes. - ANSWER: charged particles capable of conducting electricity.
Electrolytes affect the amount of water in your body, the acidity of your blood (pH),
your muscle function, and other important processes. You lose electrolytes when
you sweat. You must replace them by drinking fluids.
Describe cations. - ANSWER: the number of ions carrying a positive charge. NA+, K,
CA+, and MG+.
Describe anions. - ANSWER: the number of ions carrying a negative charge. CL-,
bicarbonate, phosphate, and sulfate.
3. Identify the major electrolytes in ICF and ECF.
a. Potassium
b. Sodium - ANSWER: POTASSIUM: regulates-renal excretion, aldosterone increases
K excretion, mvmt into and out of cells, insulin helps move K into cells; tissue
damage and acidosis shift K out of cells into ECF SODIUM: regulates-renal absorption
or excretion, aldosterone increases Na+ reabsorption in collecting duct of nephrons
Discuss the four major mechanisms of fluid and electrolyte movement. - ANSWER:
DIFFUSION: occurs when two solutes of different concentrations are separated by a
semipermeable membrane. molecules move from higher to lower concentrations.
OSMOSIS: water moves across cell membranes from less con. sol. to more con. sol.
(capillary membrane) FILTRATION: fluids and solutes move together across a
membrane from high pressure to low pressure areas. ACTIVE TRANSPORT: moves
and holds sodium and potassium against their diffusion gradients.
, Compare hydrostatic and osmotic pressure. - ANSWER: HYDROSTATIC PRESSURE: the
pressure exerted by a fluid within a closed system on the walls of the container in
which it is contained.
OSMOTIC PRESSURE: the power of a solution to pull water across a semipermeable
membrane. The solution with a higher concentration exerts a higher osmotic
pressure.
Define osmolality. - ANSWER: the concentration of solutes in the body fluids.
Determined by the total solute concentration within a fluid compartment and is
measured as parts of solute/kg of water.
2. Compare the following
a. isotonic
b. hypertonic
c. hypotonic solutions - ANSWER: ISOTONIC- has same osmolality as ECF...(0.9%
Na+Cl) HYPERTONIC- has a higher osmolality than ECF...(3% Na+Cl) HYPOTONIC-
have a lower osmolality than ECF...(0.45Na+Cl)
Discuss the role of the following in the control of fluid and electrolyte balance. Blood
pressure - ANSWER: If blood pressure/blood flow to the kidney's decreases, renin is
released, which causes the conversion of angiotensin to angiotensin I to angiotensin
II which acts directly on the nephrons of the kidney's and promotes sodium and
water retention. Also it stimulates the release of aldosterone which promotes
sodium retention in the distal nephron. so ultimately BP is increased as well as renal
perfusion.
Colloids - ANSWER: plasma proteins are colloids and exert a pressure called colloid
osmotic pressure. This holds the water in the plasma and when necessary pulls water
from the interstitial space into the vascular compartment. This helps to maintain
vascular volume.
Kidneys - ANSWER: excrete hydrogen ions and retain bicarbonate. kidney's regulate
the volume and osmolality of ECF by REGULATING WATER AND ELECTROLYTE
EXCRETION.
ADH - ANSWER: synthesized in the anterior portion of the hypothalamus and acts on
the collecting ducts of the nephrons by making the collecting ducts become more
permeable to water ALLOWING MORE WATER TO BE ABSORBED INTO THE BLOOD.
blood volume, stress, temperature, pain and opiates affect release of ADH.
Aldosterone - ANSWER: promotes SODIUM RETENTION in the distal nephron,
INCREASING THE BLOOD VOLUME.
Parathyroid hormone [S] - ANSWER: increases reabsorption of phosphate (major
anion in ICF), causing more to be excreted through urine and increases the amount
of calcium in circulation
