Fluid, Electrolyte, and Acid-Base Regulation

Question 1

electrolytes

Answer 1

minerals in the body that are able to conduct electrical charges. In the human body, electrolytes (essential to sustain life) are found in the blood, urine, tissues, and other body fluids.

Question 2

common electrolytes

Answer 2

potassium
sodium
calcium
magnesium

Question 3

levels of electrolytes can be evaluated by performing metabolic panels such as

Answer 3

basic metabolic panel (BMP)
completely metabolic panel (CMP)

Question 4

basic metabolic panel (BMP)

Answer 4

a blood test that provides information regarding electrolyte and fluid balance and includes regarding renal function and glucose levels.

Question 5

complete metabolic panel (CMP)

Answer 5

a blood test that provides information regarding electrolyte and fluid balance. In addition to those findings included in the BMP, the CMP also includes information regarding the body’s metabolism including protein and liver function.

Question 6

Electrolytes are responsible for the following functions within the body:

Answer 6

• maintaining the balance of water in the body
• balancing the blood pH (acid-base) level
• moving nutrients into the cells
• moving wastes out of the cells
• maintaining proper function of the body’s muscles, heart, nerves, and brain

Question 7

basic metabolic panel (BMP) checks:

Answer 7

blood urea nitrogen (BUN)
carbon dioxide (CO2)
creatinine (CR)
glucose
chloride (Cl-)
potassium (K+)
sodium (Na+)
calcium (Ca+)

Question 8

comprehensive metabolic panel (CMP) checks:

Answer 8

blood urea nitrogen (BUN)
carbon dioxide (CO2)
creatinine (CR)
glucose
chloride (C-)
potassium (K+)
sodium (Na+)
calcium (Ca+)
liver enzymes
alkaline phosphate (ALP)
alanine transaminase (ALT)
aspartate aminotransferase (AST)
bilirubin (total)
protein (total)
albumin

Question 9

The average person’s weight consists of ________ to _________ water.

Answer 9

one-half; two-thirds.

Question 10

osmolality

Answer 10

a measurement of the solutes within a solution.

Question 11

What is the most frequently used laboratory indicator of the body’s fluid status?

Answer 11

serum osmolality

Question 12

What is the expected reference range of serum osmolality?

Answer 12

285 to 295 mOsm/kg.

Question 13

As body water decreases, the concentration of solutes ___________.

Answer 13

increases

Question 14

What is the expected reference range for urine osmolality?

Answer 14

50 to 1,200 mOsm/kg.

Question 15

The body’s water is located:

Answer 15

both within the cells and outside the cells

Question 16

Intracellular space

Answer 16

the largest fluid compartment
holding 67% of the body’s water

Question 17

extracellular space

Answer 17

comprise the interstitial space (contains 25% of the body’s water) and the intravascular space (contains the remaining 8% of body water).

Question 18

osmosis

Answer 18

the movement of water across a semi-permeable membrane from an area of higher concentration of water molecules and a lower concentration of solutes to one of a lower concentration of water molecules and a higher concentration of solutes, such as fluid moving into or out of a cell, in an effort to maintain homeostasis.

Question 19

lamina terminalis

Answer 19

sits at the edge of the hypothalamus; senses the body’s water balance by monitoring the osmolality in the ventricles of the brain.

Question 20

How much does it take to alert the brain’s sensors to a decrease in the body’s fluid volume?

Answer 20

as little as a 1% increase in serum osmolality.

Question 21

To maintain the body’s water balance, as serum osmolality rises, what impact does antidiuretic hormone have?

Answer 21

The hypothalamus stimulates the posterior pituitary to release antidiuretic hormone (ADH), also known as vasopressin, which acts on the nephrons of the kidneys. The collecting ducts of the nephrons respond to ADH by increasing the reabsorption of water, decreasing the excretion of urine, and increasing the fluid volume of the body.

Question 22

The kidneys also help to maintain fluid and electrolyte balance by:

Answer 22

removing cellular wastes and excess fluid through urination. Through this process, the kidneys maintain homeostasis within the body by filtering the blood and eliminating wastes, but also by returning needed water and electrolytes back into the circulation where they are needed.

Question 23

Risk factors for fluid and electrolyte imbalances; factors that can contribute:

Answer 23

dehydration
hypovolemia
overhydration
certain medications
heart, kidney, or liver disorders
incorrect intravenous fluids or feedings
profuse sweating, vomiting, diarrhea

Question 24

Potassium (K+)

Answer 24

3.5 to 5 mEq/L

Question 25

Sodium (Na+)

Answer 25

136 to 145 mEq/L

Question 26

Calcium (Ca+)

Answer 26

9 to 10.5 mg/dL

Question 27

Magnesium (Mg+)

Answer 27

1.3 to 2.1 mEq/L

Question 28

diffusion

Answer 28

movement of solutes, such as electrolytes, from an area of high concentration (such as within a cell) to an area of low concentration (such as the intravascular area). This process continues until there are equal numbers of solutes inside and outside the cell.
Diffusion is a passive process, meaning it does not require the use of any energy.

Question 29

active transport

Answer 29

involves the use of energy to move solutes from an area of lower concentration to one of higher concentration. An example is the movement of sodium and potassium into and out of the cells through the sodium-potassium pump.

Question 30

potassium

Answer 30

the body’s largest intracellular electrolyte. Its function is to support the transmission of electrical impulses of the body’s nerves and muscles. Plays a major role in the conduction of nerve cells within the heart. The body maintains potassium levels within a narrow range. The recommended dietary allowance (RDA) for daily intake of potassium is 3,400 mg for adult males and 2,600 mg for adult females. The kidneys are responsible for the primary excretion of potassium (90%), while the rest is lost through sweat and the digestive tract.

Question 31

hypokalemia

Answer 31

potassium level below expected reference range of 3.5 to 5 mEq/L.

Question 32

Critical values occur at less than ___ mEq/L for adults and less than ____ mEq/L for newborns.

Answer 32

3; 2.5.

Question 33

hypokalemia can occur from several causes:

Answer 33

medications
certain cardiac conditions
gastrointestinal losses
metabolic alkalosis
decreased oral intake of potassium
excessive alcohol use
chronic kidney disease
diabetic ketoacidosis
excessive sweating
folic acid deficiency

Question 34

What is the most common cause of hypokalemia?

Answer 34

loss of potassium from the kidneys or gastrointestinal tract