Chapter 32: Fluid and Electrolyte Balance

Question 1

Objective:

Explain the importance of fluid and electrolyte balance in the body.

Answer 1

fyi

Question 2

Amount of water & electrolytes entering body should = ?

Answer 2

amount of water & electrolytes leaving body

Question 3

Total body water

Considered as a % of total body weight
It Differs due to a person’s what 3 things?

Answer 3

_ age, body fat and gender_

Question 4

Total body water:

• Newborn=
• 10 years old=
• Adolescence=
• Adult=

Answer 4

Newborn= 75% of body weight

10 years old=percentage decreases rapidly

Adolescence= will vary due to gender & amount of fat tissue, differences which account for about 10% variation in total %

Adult=decrease to 45% of total body weight

Question 5

fyi

Total body water

infants will have the highest % of body weight, and decreases as we age.

Answer 5

fyi

Question 6

what are the Body Fluid Compartments (2)

Answer 6

• Extracellular fluid (ECF)
• Intracellular fluid (ICF)
• Total Body Fluid = ECF + ICF

Question 7

• Anything outside of the cell
• Provides constant environment for cells
• Transports substances to and from cells

Includes- Interstitial fluid, plasma (2 main), lymph, & transcellular fluid like CSF/ joint fluid/ and humors of the eye.

Answer 7

Extracellular Fluid

Question 8

what fluid Facilitates chemical reactions inside of cells?

Answer 8

Intracellular fluid

Question 9

Chemical Content of Fluid

anything that will break up into charged particles or ions

Answer 9

Electrolytes

Question 10

what are theses?

Ca2+
Na+
K+
Mg2+
Cl-
HCO3-
HPO4-

Answer 10

Anions and Cations that serve critical role in the body

Question 11

cation will be atracted to the negative or positive electrodes?

Answer 11

negative

a cation is positvely charged

Question 12

negeatilvely charged ions that attract positve electrodes ?

Answer 12

anions

Question 13

Extracellular fluid

Answer 13

Blood Plasma and interstitial fluid (figure 32-3)

Question 14

Almost identical

• The main difference between blood plasma and interstitial fluid is the amount of ______________, blood plasma has more proteins.

Answer 14

protein anions

Question 15

Blood Plasma and interstitial fluid (figure 32-3)

Major cation is ?

Answer 15

sodium

Question 16

Intracellular fluid

• Differs greatly from extracellular fluid
• Major cation is?

Answer 16

K+ = potassium

Question 17

Chemical Structure of Body Fluids

the Function is to?

Answer 17

maintain homeostasis

differening charge or valence helps us move water.

Question 18

WATER is added to the body through…

Answer 18

the digestive tract by ingesting food & fluids. It is also added to the bloodstream by cell catabolism.

Question 19

WATER is lost from the body through…

Answer 19

Urine, feces, perspiration, exhaled air (water vapor)

Question 20

Input (intake) vs Output

look at page 1008 (32-5)

all the ways it enters and exits the body.

Answer 20

look

Question 21

The rules of fluid balance…

Answer 21

• Balance maintained only if intake equals output
• Mechanisms are available to adjust input & output (RAAS (activates aldosterone) system, ANH, ADH)
• The most rapid way to adjust fluid balance is by controlling water movement between fluid compartments (ICF and ECF) of the body. We will maintain normal blood volume at the expense of interstitial fluid volume.

Question 22

Maintaining Fluid Balance (normally)

Primary mechanism

Answer 22

Adjust urine output via hormone systems

Question 23

Maintaining Fluid Balance (normally)

Secondary mechanism

Answer 23

Adjust fluid intake

Question 24

Maintaining Fluid Balance (normally)

what mechanism below

• Decreasing intake causes our “thirst center” to activate
• Receptors in the brain tell the hypothalamus to release ADH hormone which lets or cerebrum know our mouths are dry and we are thirsty

Answer 24

Secondary mechanism

Question 25

2 Factors determine urine volume:

Answer 25

1. Glomerular filtration rate generally is constant 2. Rate of tubular reabsorption of water fluctuates and can be adjusted

Question 26

* Under normal conditions it adjusts to intake * It is influenced by the hormones ADH (from the pituitary), ANH(from the heart, and aldosterone (from the adrenal cortex) (feedback loops can be seen in figure 32-8)

Answer 26

* _Rate_ of tubular reabsorption of water fluctuates and can be adjusted

Question 27

* Rate of respiration and volume of sweat alter fluid output * Hyperventilate- increases respiration rate and sweat production * Dehydration- fluid output exceeds input * Vomiting, diarrhea, or intestinal drainage can also produce fluid and electrolyte imbalances

Answer 27

Factors that alter fluid loss 
under abnormal conditions

Question 28

Insufficient body fluid resulting from inadequate intake OR excessive loss OR both.

Answer 28

Dehydration

Question 29

Dehydration Symptoms vary

Answer 29

* Simple thirst * Poor concentration * Cannot regulate excess temperature * Dizziness, weakness * Muscle spasms * Kidney failure * Concentration of solutes in the extracellular fluid will increase

Question 30

Starlings Law of capillaries= The control mechanism for water exchange between plasma and interstitial fluid consists of **_4 types of pressure_**. Two directed in and 2 directed out.

Answer 30

* Blood colloid osmotic pressure ( pushes into capillaries) * Blood hydrostatic pressure (push out of capillaries) * Interstitial fluid hydrostatic pressure (push into capillaries) * Interstitial fluid colloid osmotic pressure (push out of capillaries)

Question 31

What law is this? The control mechanism for water exchange between plasma and interstitial fluid consists of 4 types of pressure. Two directed in and 2 directed out.

Answer 31

Starlings Law of capillaries

Question 32

Starlings Law of Capillaries the rate and direction of movement of fluid electrolytes between plasma and interstitial fluid depends mainly on the\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ inside and outside the vessel.

Answer 32

pressure differences

Question 33

Starlings Law of Capillaries the rate and direction of movement of fluid electrolytes between plasma and interstitial fluid _hydrostactic** is the is highest inside the vessel at the arterial end of the capillaries and lowest inside the vessel at the ::::::::**_

Answer 33

venous end of capillaries.

Question 34

Fluid Shifts ## Footnote Transfer of water: There is fluid movement in and out of structures in order to deliver what the body needs, but no net transfer of water occurs between ........?

Answer 34

blood and interstitial fluid.

Question 35

* Large amounts of fluid in intercellular tissue spaces * Lung * Brain * Subcutaneous space of dependent body areas * An excessive amount of fluid in the interstitial space Can be localized or generalized Causes swelling/enlargement of the tissues More visible in dependent areas of body

Answer 35

Edema

Question 36

Some Things That Lead to Edema pg 1016 32-13

Answer 36

* **_Retention of electrolytes, especially sodium, in extracellular fluid (Pitting edema)_** * **_can be caused by increased aldosterone secretion_** * Increased blood volume or capillary blood pressure (such as in inflammation) * Decrease in concentration of plasma proteins (albumin) normally retained in blood * This can be the result of increased capillary permeability caused by infection, burn or shock.

Question 37

ex) sweat -----\> decreases H2O bloldd----\> Blood becomes more concentratd with electrolytes---\> more fluid is sucked into blodd by BCOP---\> lost fluid IF-----\> more fluid is sucked into the IF by IFCOP form the intercellular fluid I C F Mrs G wrote this on board

Answer 37

how we maintain blood pressure

Question 38

* The plasma membrane plays a critical role in the regulation of ICF composition * Transfers of fluid between IF (interstitial) and intracellular work very similarly to transfers between IF and plasma; again driven by hydrostatic and colloid osmotic pressures.

Answer 38

Regulation of Water and Electrolyte Levels in Intracellular Fluid (ICF)

Question 39


Fluid levels in ICF

Answer 39

* Water movement is regulated * Interstitial fluid and intracellular fluid hydrostatic and colloid osmotic pressure regulate water transfer * Colloid osmotic pressure is _chief_ regulator of water transfer * Colliod osmotic pressure is associated with _potassium and sodium_ levels

Question 40

* ***_Interstitial fluid and intracellular fluid electrolyte concentration are main determinants of colloid osmotic pressure_*** * ***_Fluid balance depends on electrolyte balance_***

Answer 40

Fluid Balance

Question 41

Regulation of Sodium and Potassium

Answer 41

Highly dependent on the amount of ADH and aldosterone secreted. The kidneys are the chief regulator of sodium levels ADH: regulates amount of water reabsorbed into blood Aldosterone: regulates sodium reabsorbed into blood Na/K pump to maintain electrical properties of cell Sodium: primary cation in ECF (therefore chloride is the primary anion in ECF) Potassium: primary cation in ICF If there is a drop in sodium or potassium, there can be a change in the fluid exchange (becomes unbalanced)

Question 42

primary cation in ECF (therefore chloride is the primary anion in ECF)

Answer 42

Sodium:

Question 43

primary cation in ICF

Answer 43

Potassium:

Question 44

In Summary Fluid balance depends on electrolyte balance and electrolyte balance depends on fluid balance.

Answer 44

fyi

Question 45

Fun Facts about electrolyte balance and exercise:

Answer 45

Posterior Pituitary Gland secretes antidiuretic hormone (ADH). Aka: Vassopressin -it reduces water loss from the body to maintain plasma volume -stimulated by: high plasma osmolality & low plasma volume due to seating (i.e. exercise

Question 46

Fun Facts about electrolyte balance and exercise:

Answer 46

* **How ADH Conserves Body water:** - Muscle activity promotes sweating - Sweating causes loss of blood plasma, resulting in hemoconcentration & increased blood osmolarity. - increased blood osmolarity stimulates the hypothalamus, which then stimulates the posterior pituitary gland - Pituitary secretes ADH - ADH acts on the kidneys increasing the water permiability of the renal tubules and collecting ducts, leading to increased reabsorption of water - Plasma volume increases so blood osmolarity decreases after exercise and water ingestion

Question 47

Fun Facts about electrolyte balance and exercise: The Renin-Angiotensin Mechanism:

Answer 47

1. Muscular Activity promotes Sweating & increases BP 2. Sweating reduces plasma volume & blood flow to kidneys 3. Reduced renal blood flow stimulates renin, released from kidneys. Renin then forms angiotensin 1, then to A2 4. Angiotensin 2 stimulates release of aldosterone from adrenal cortex 5. Aldosterone increases Na+ and H2O reabsorption from the renal tubules 6. Plasma volume increases, urine production decreases with water and sodium intake, therefore electrolyte balance.

Question 48

Chapter Review Questions

Answer 48

``` To help review this chapter, do the following review questions on pgs 1023-1024 #s 3, 4,6,7,10,12,14,15,17, 18 ```

Question 49

fyi adh is going to save water aldosterone is going to save electrolytes where sodium goes water goes.

Answer 49

fyi