Fluid And Electrolyte Balance Outline

Question 1

Fluid balance

Answer 1

Homeostasis of fluids; the volumes of interstitial fluid, intracellular fluid, and plasma and total volume of water remain relatively constant.

Question 2

Fluid imbalance

Answer 2

Means that the total volume of water in the body or the amounts in one or more of its fluid compartments have increased or decreased beyond normal amounts.

Question 3

Electrolytes

Answer 3

Substances such as salts that dissolve or break apart in a water solution to form electrically charged atoms (or groups of atoms) called ions.

Question 4

Electrolyte balance

Answer 4

Various types of body fluids serve differing functions in different areas of the body. To do so, each type of body fluid must maintain differing levels and types of electrolytes within a very narrow range of normal. For example, blood, lymph, intracellular fluid (ICF), interstitial fluid (IF), cerebrospinal fluid (CSF), and joint and eye fluids all depend on complex homeostatic mechanisms to adjust and maintain normal levels of appropriate electrolytes.

Question 5

Body “average” Fluid Volumes are based on healthy nonobese young adults

Answer 5

Males weighing 154 pounds will have on average about 60% of their body weight, nearly 40 L, as water.
Young females average about 50% water.

Question 6

Why are Body Fluid Volumes based on healthy nonobese young adults?

Answer 6

The adipose or lipid tissue contains the least amount of water of any body tissue. The more lipids present in the body, the less the total water content per kilogram of body weight.

Question 7

As a percentage how much of an infant’s total body weight is water?

Answer 7

Is more than an adult of either sexes. It may account for 75% to 80% of total body weight. The percentage of water is even higher in premature infants.

Question 8

Why is the need for a high water content in the early stages of life important?

Answer 8

As most of their total body weight is water; fluid imbalances in infants caused by diarrhea, for example, can be serious.

Question 9

How much percentage of body water decrease from infancy to elderly?

Answer 9

Body water decreases rapidly during the first 10 years of life. By adolescence there is a 10% variation in body fluid volumes.
In elderly the amount of water per kilogram of body weight decreases due to a decrease in muscle mass (65% water) and an increase in lipid (20% water.)

Question 10

Fluid Compartments

Answer 10

Any of the areas in the body where the fluid is located; for example, interstitial fluid or intracellular fluid.

Question 11

interstitial fluid

Answer 11

Fluid located in the microscopic spaces between the cells

Question 12

intracellular fluid

Answer 12

A fluid located within the cells; largest fluid compartment

Question 13

Extracellular fluid (ECF)

Answer 13

The water found outside of cells located on 2 compartments between (interstitial fluid) and in the blood (plasma.)
Smaller volume of lymph and trans cellular fluids are part of the extracellular fluid compartment.

Question 14

How is homeostasis of the total volume of water in the body maintained or restored?

Answer 14

Primarily by devices that adjust output (by adjusting urine volume) to intake and secondarily by mechanisms that adjust fluid intake.

Question 15

Out of the 2 mechanisms for maintaining fluid balance is more important?

Answer 15

Is the adjusting of its fluid output so that it equals its fluid intake.
As long as output and intake are equal, the total amount of water in the body does not change. The 3 main sources of fluid intake is:
1. Water in the foods we eat
2. Liquids we drink
3. Water formed by catabolism of nutrients (cellular respiration)

Question 16

What are the main avenues of water output by the body?

Answer 16

1. Water vapor lost when we exhale
2. Sweat that evaporates from the skin
3. Urine output by the kidney
4. Water lost in the feces

Question 17

A number of factors act as mechanisms for balancing plasma, interstitial fluid (IF) & intracellular fluid (ICF) volumes. What are the 3 main factors?

Answer 17

1. Regulating fluid output
2. Regulating fluid intake
3. Exchanging fluids between compartment and from place to place within the body

Question 18

What 4 organs are involved in fluid output from the body and how is it lost?

Answer 18

. Lungs (water in expired air)
. Skin (by diffusion & sweat)
. Kidneys (urine)
. Intestines (in feces)

Question 19

What is Antidiuretic Hormone Mechanism and what is an Antidiuretic?

Answer 19

Antidiuretic Hormone (ADH) release from the posterior pituitary increases as the Extracellular Fluid (ECF) volume of the body decreases below normal.

ADH promotes water reabsorption from the kidney tubule back into the blood which reduces urine volume by retaining more water in the body. This ADH reduces water output from the body.

Question 20

Explain the Aldosterone Mechanism and how it uses ADH and Aldosterone to be a water-conserving hormones that helps maintain a constant volume of ECF (Extracellular Fluid) in the body?

Answer 20

Aldosterone from the adrenal cortex works with ADH to reduce water output further. Aldosterone increases Na+ (sodium) reabsorption from the kidney tubules causing water reabsorption into the blood to also increase. Causing the body to retain water that would otherwise be lost in the urine.

Question 21

Explain the Atrial Natriuretic Hormone Mechanism and how it used the
Atrial Natriuretic Hormone (ANH) to be a water-loss hormone or diuretic hormone?

Answer 21

Atrial natriuretic hormone (ANH) from the atrial wall of the heart which increases urine volume. ANH is released when blood volume is higher than normal, which stretches the atrium. ANH promoted sodium loss from the blood into kidney tubules causing water to also be lost from the blood which increases loss of water through urine.

Question 22

What is more important than the body adjusting fluid intakes?

Answer 22

Factors that adjust output, such as electrolytes and blood proteins are far more important