Module 8 - Fluid and Electrolyte Balance

Question 1

Substances that dissociate in solution to form a charged particle

Answer 1

Electrolytes

Question 2

Sodium

Answer 2

135-145 mEq/L

Question 3

Potassium

Answer 3

3.5-5.0 mEq/L

Question 4

Chloride

Answer 4

98-106 mEq/L

Question 5

Bicarbonate

Answer 5

24-31 mEq/L

Question 6

Calcium

Answer 6

8.5-10.5 mg/dL

Question 7

Magnesium

Answer 7

1. 3-2.1 mg/dL

1. 8-3.0?

Question 8

Pushing force exerted by a fluid. Arterial capillary pressure is about 30 mmHg and venous is 10 mmHg

Answer 8

Hydrostatic pressure

Question 9

Pulling force of plasma proteins that cannot pass through the capillary membranes; assist the movement of fluid back into the capillary

Answer 9

Colloid osmotic pressure

Question 10

Fluid trapped in one of several possible transcellular spaces

-This fluid is not available for ECF or ICF uses, since it is trapped or “sequestered”

Ex. Pleural effusion, pericardial effusion, ascites

Answer 10

“Third Spacing”

Question 11

Movement of water from an area of lower concentration to an area of greater concentration of solutes (electrolytes)

Answer 11

Osmosis

Question 12

Obligatory urine output

Answer 12

300-500 ml/24 hrs

Question 13

A disorder causing loss of ability to sense thirst

Answer 13

Hypodipsia

Question 14

“Dehydration”

Answer 14

Fluid volume deficit

Question 15

equal loss of water and sodium (common cases: vomiting, diarrhea, misuse of diuretics)

Answer 15

Isotonic fluid volume deficit

Question 16

More water loss than sodium. (osmotic diuresis, excessive sweating, loss of thirst sensation, unable to obtain or drink fluids)

Answer 16

Hypertonic fluid volume deficit

Question 17

more sodium is lost than water. Serum Na+ is low

excess renal losses of Na+, aldosterone deficieny

Answer 17

Hypotonic fluid volume deficit

Question 18

Fluid volume deficit symptoms

Answer 18

• Dry skin and mucous membranes
• decreased urine output
• in babies, depressed fontanel (soft spot on top of head)
• B.P may be decreased with heart rate increased

Question 19

Physiological consequences of severe fluid volume deficit

Answer 19

Inadequate kidney perfusion - can result in acute renal failure

Steps:

• RECOGNITION
• Treatment with IV fluids or blood

Question 20

Fluid volume EXCESS causes:

Answer 20

• impaired kidney function - decreased urine output
• heart failure or cardiac insufficiency
• excessive intake of water and sodium
• fluid retention related to stress response

Question 21

Fluid volume EXCESS s/s

Answer 21

• acute weight gain
• increased bp r/t increased vascular volume
• strong bounding pulse
• possible dyspnea
• possible jugular venous distention (JVD)
• edema

Question 22

_________ a blood test that shows the % or proportion of RBCs to the plasma (fluid)

Answer 22

Hematocrit

40-50% m
37-47% f

Question 23

_______ a lab test that measures the density of urine, compared to the density of water

Answer 23

Urine Specific Gravity

1.010-1.025

Question 24

Reflects the kidney’s ability to produce a concentrated or dilute urine based on serum osmolality and the need for water conservation or excretion

Answer 24

Urine Osmolality

Question 25

Drugs to decrease fluid volume: Diuretics

Answer 25

• Furosemide (Lasix)
• Hydrochorothiazide (HCTZ)
• Spironlactone (aldactone)

Question 26

Mechanism of Action - acts in the ascending loop of Henle to block sodium and chloride reabsorption, causing profound diuresis

Answer 26

Lasix (furesomide)

Question 27

Mechanism of Action - blocks reabsorption of sodium and chloride in distal convoluted tubule; produces much less loss of urine than lasix and adequate urine function must be present

Answer 27

Thiazide diuretic (Hydrochlorothiazide)

Question 28

Mechanism of action: blocks the actions of aldosterone in the distal nephron, promotes sodium uptake in exchange for potassium secretion. not as much diuresis as thiazides

Answer 28

Spironolactone (aldactone)

useful for blocking loss of potassium when pt also on lasix

Question 29

a sign of excess interstitial fluid

Answer 29

Edema

Question 30

potential etiologies of edema

Answer 30

• Increased hydrostatic pressure
• lowered plasma oncotic pressure (decrease in plasma proteins - albumin)
• Increased capillary permeability
• Lymphatic channel obstruction