fluid and electrolytes

Question 1

about 2/3 of the total body water is in the ___ while the remaining 1/3 is in ___

Answer 1

• 2/3 is in intracellular fluid

- 1/3 is in the extracellular fluid

Question 2

extracellular fluid consists of

Answer 2

interstitial fluid and lymph (15% body weight), plasma (3% body weight), and the transcellular fluids, which include GI fluid, urine, and CSF.

Question 3

the main cation in the intracellular fluid (ICF) is __, but the main cation in extracellular fluid (ECF) is __

Answer 3

• ICF: K+

- ECF: Na+

Question 4

The presence of a widened anion gap signifies the presence of a _______

Answer 4

metabolic acidosis due to a nonchloride containing acid.

Question 5

Persistently low anion gaps are a serious sign of _________

Answer 5

possible malignancy, i.e., myeloma

Question 6

what two acids do not have Cl- as their counter-ion so may contribute to a larger anion gap?

Answer 6

acetoacetic acid and lactic acid

Question 7

which clinical condition is associated with a large anion gap do to the presence of acetoacetic acid?

Answer 7

diabetic acidosis

Question 8

Total osmolality or osmotic pressure of a
solution is equal to the sum of the
____

Answer 8

osmotic pressures or osmolalities of all

solutes present

Question 9

who contributes more to the osmolality of serum, proteins or electrolytes?

Answer 9

electrolytes by far

Question 10

what is the osmolal gap best used to detect

Answer 10

However, the osmolal gap is most effectively used to detect and follow poisonings with nonelectrolytes such as acetone, ethanol, methanol, ethylene glycol, and some others

Question 11

osmolal gap values up
to 10 (moderate increases) are associated with \_\_\_\_\_\_

Answer 11

-ketoacidosis, renal acidosis, and lactic

acidosis

Question 12

In the venous part of capillaries, oncotic pressure _____ hydrostatic pressure, and fluid is drawn into the ____

Answer 12

• prevails over hydrostatic pressure

- vascular lumen

Question 13

Why would we see edema in a condition like Kwashiokor?

Answer 13

Inadequate protein in diet leads to insufficient synthesis of albumin. A reduction in plasma oncotic pressure, which occurs, for instance, as a consequence of a decrease in the plasma albumin concentration, results in the movement of fluid into the extravascular space and in edema.

Question 14

What is the major function of kidneys?

Answer 14

Kidneys maintain the composition, osmolality, and volume of the ECF and also control the acid-base balance

Question 15

The kidneys produce _____ involved in calcium
homeostasis, and ______which
controls the production of erythrocytes

Answer 15

-calcitriol (1α,25-dihydroxycholecalciferol,
1,25(OH)2D3)

-erythropoietin

Question 16

where does plasma filtration occur?

Answer 16

at the glomeruli in the kidney

Question 17

where is sodium reabsorbed in the nephron?

Answer 17

-More than 80% of filtered sodium is
actively reabsorbed in the proximal tubule
-sodium is also reabsorbed in the ascending loop of Henle
-also at distal convoluted tubule but…A different mechanism
operates in the distal tubule, where
sodium reabsorption is stimulated by
aldosterone and is coupled with the
secretion of hydrogen and potassium ions.

Question 18

In clinical practice, __ and ___
are first-line tests in the diagnosis of renal
failure.

Answer 18

serum urea and creatinine

Question 19

The most common cause of

severe hyperkalemia is ___.

Answer 19

renal failure: in this condition

potassium cannot be adequately excreted in the urine

Question 20

how are electrolytes determined?

Answer 20

ion-specific electrodes (ISE’s)

Question 21

what is plasma?

Answer 21

liquid, cell free part that has been treated with anticoagulants

Question 22

serum

Answer 22

liquid part of blood that has been collected after coagulation

Question 23

where is angiotensin-II synthesized??

Answer 23

the blood

Question 24

Renin is synthesized by juxtaglomerular cells of the kidney and ultimately leads to production of ___

Answer 24

angiotensin II

Question 25

what does angiotensin II do?

Answer 25

kidneys: increase Na+ retention, H2O retention
Brain: corticotropin and adiuretin (thirst)
adrenals: Aldosterone production
blood vessels: vasoconstriction

Question 26

Aldosterone regulates __ and ___ homeostasis

Answer 26

K+ and Na+

Question 27

what is commonly found in hypertension

Answer 27

hyperaldosteronism

Question 28

when is renin secreted??

Answer 28

sodium levels decline or there is a fall in blood

pressure.

Question 29

when would you use an ACE inhibitor?

Answer 29

to treat hypertension or CHF

Question 30

elevated levels of Atrial natriuretic peptide (ANP) are found during ___ states

Answer 30

hypervolemic states and CHF

Question 31

BNP and NTpro-BNP are sensitive, diagnostic markers for ____ in patients.

Answer 31

heart failure

Question 32

_____ determines the final volume and

concentration of the urine

Answer 32

Vasopressin

Question 33

vasopressin

Answer 33

Vasopressin is synthesized in the
hypothalamus and is transported along axons to the
posterior pituitary where it is stored before being
further processed and released. It binds to a receptor
located on the membranes of tubular cells in the
collecting ducts. The receptor is coupled to G-proteins
and activates protein kinase A (PKA). PKA
phosphorylates aquaporin 2 (AQP2), which stimulates its
translocation to the cell membrane, increasing water
reabsorption in the collecting duct.

Question 34

Vasopressin deficiency causes the condition known as ______

Answer 34

diabetes insipidus

Question 35

inappropriate antidiuretic hormone secretion (SIADH)

Answer 35

an excessive secretion of vasopressin may occur
following major trauma or surgery. This is known as the syndrome of inappropriate antidiuretic hormone secretion (SIADH), and leads to water retention.