1. CHPT 9 WATER
Nutrition

2. Water
Humans can’t live but for a few days without water…10-14 days

3. Why is water important? It is the main component of all body cells
It makes up 50-60% of the body wt in normal adults
Men have more water wt due to the size of their muscles and muscle tissue
Newborns have the highest % of H2O =75% of their body is water

4. Other functions of water
Solvent for nutrients and body wastes
Aids in chemical reactions
Transports nutrients and wastes in blood
Needed for hydrolysis and digestion
Lubricates joints
Regulated body temp by evaporation of perspiration
Serves as a shock absorber

5. Water content in muscle is greater than water content in fat

6. Body Water Content Obese Normal Muscular 40% 60% 70%

8. 2 compartment of body water
1. Intracellular – is the water within the cells, it’s approx. 65% of total body fluid
2. Extracellular – is the water outside of the cells, approx. 35% of total body fluid
(includes intravascular & interstitial fluid)

9. What do these compartments mean?
Intracellular – is inside the cell where K+ is found
Intravascular – inside the blood vessel
Interstitial – around the tissues
Extracellular – is both intravascular (inside of the blood vessel) AND interstitial…this is where Na+ is found

11. How does the “pie” from the previous slide fit into the body exactly?
TIP:
Water should always be in the 1st space first
Water should always be in the 2nd space second in order for the normal body to function 
And we try not to allow water to move to the 3rd space

12. Cell = 1st space Extracellular (interstitial & intravascular) = 2nd space Abdomen and feet = 3rd space (ascites)
1 cell
2 blood
vessel
(Intravascular)
2 extracellular/
interstitial
1 cell

13. Best source of water? Is in drinking water
Beverages of all other types are 2nd best
Food contains water, like fruits, soups, jello, milk, vegetables
Energy metabolism produces H20

14. Estimated daily fluid intake for adults
Ingested liquids 1,500ml
Water in foods ml
Water from oxidation ml
__________
TOTAL ,400ml

15. HOMEOSTASIS Keeping the body = or at a balance
Our body has this mechanism related to fluids called:
Fluid & electrolyte balance
This balance is for too little water (dehydration) or fluid overload (too much water) in the body…both can occur

16. Fluid & electrolyte balance
Water lost by healthy individuals through feces, perspiration and the respiratory tract, must be replaced in both volume and in electrolyte content

17. Specific Gravity (S.G.)
This is a measurement of the weight of the particles in urine compared to the water in urine
If you have lots of particles = heavy urine=big number like
If you have diluted urine due to excess urination = light weight urine = low number like

18. Urine Specific Gravity
Normal S.G. complete range
Normal urine is
This means that urine is straw yellow in color and that the patient is urinating a minimum of 30mL/hr
Small machine or test strip can tell you the S.G. of urine

19. Equipment to test S.G.

20. Vomiting & Diarrhea
This type of illness where there is great water loss, must be replaced quickly
IVFs in this case would be needed

21. Symptoms of dehydration
Hypotension - (not enough fluid in the blood vessels to be pumped everywhere throughout your body)
Thirst
Eyes are sunken in
Mucus membranes are dry
Dry skin/decreased skin turgor
Fever
Tachycardia
Mental disorientation
Specific gravity of <1.010 = clear,
clear urine

22. Treatment of this water loss
Replacement of the electrolytes and fluids
IVFs are a replacement if the amount lost is great
Drinking by mouth is preferred

23. Sensible vs. insensible loss
SENSIBLE LOSS – is noticeable loss of water as in urine loss…normal loss
INSENSIBLE LOSS – unnoticed, water loss is in feces, perspiration and respiration

24. Normal daily water loss
The body must excrete 500ml of water as urine each day in order to get rid of the waste products of metabolism
This is 500 divided by 24 hrs= 20.8cc/hr
+ what we sweat and breathe off therefore,
We should be excreting at least 30cc/hr minimum

25. DEHYDRATION & OSMOSIS
Water moves through the cell walls by this mechanism
Remember water likes to dilute “stuff”
Therefore, water moves from an area with less stuff, to an area with lots of stuff to dilute it
Where salt or protein is…water follows

26. ELECTROLYTES Na+ Cl- K+
These electrolytes maintain the balance between intracellular and extracellular fluid
Intravascular & Interstitial

27. Potassium K+
Is the principal electrolyte in INTRAcellular fluid

28. Sodium Na+
Is the principal electrolyte in extracellular fluid

29. Why we get thirsty?
If the cell (1st space) becomes dehydrated, as in the body lost water, we become thirsty

30. Why else can you become thirsty???
When the electrolytes in the extracellular fluid are increased (hypertonic solution as in the consumption of high sugar or salt), the intracellular fluid moves out of the cell to the extracellular fluid to try and dilute it or push the particles away from each other
This causes…..

31. Osmosis
The water from the inside of the cell (intracellular) to move out of the cell (osmosis) shrinking the cell = dehydration of the cell occurs
= thirst

32. Is there any safety mechanism in the body to prevent this from happening?
YES…….. 2 mechanisms try and prevent the body from getting dehydrated:
1) ADH
2) Aldosterone

33. The hypothalamus saves the day!
It is responsible for regulating appetite
and thirst.
The hypothalamus
is located at the
base of the brain

34. During this time…
When the cell (1st space) releases all of its water to the extracellular fluid to try and separate those particles to dilute them, the cell shrinks and the body says “ught ohhhh”
The hypothalamus sends a message to the pituitary gland to secrete ADH (antidiuretic hormone) when the electrolytes become too concentrated in the blood

35. PITUITARY GLAND Known as the “Master Gland”
It helps keep water in the blood via the kidneys
It controls growth by sending growth hormones
It aids in releasing pitocin and sending breastmilk out of the breasts
It aids in reproduction by sending sex hormones out to make a baby

36. ADH (anti-diuretic hormone)
By the hypothalamus sending the pituitary gland a message to excrete ADH, the ADH goes to the kidney tubule and tells it to hold water and to reabsorb that water back into the bloodstream, rather than to excrete it or urinate it out, ADH is (against diuresis), anti-diuretic
If you didn’t have ADH, then the water that was in the cells would now move out into the extracellular space to help dilute the high sugar or high salt you ate, the cells become dehydrated, then the kidney would pee out the water in the extracellular fluid and the body would be empty of water…very bad

37. What do you say when this process happens in the body?
When the cell becomes empty of water because the ICF moved to the ECF to push particles apart, your mouth and tongue know your cells are empty of water and your hypothalamus knows you are thirsty….so you say “boy am I thirsty” and you drink water

38. So what does ADH do for the body?
When that ADH stops the water from leaving the renal tubule, it can then be absorbed back into the blood and extracellular space and help push fluid and salts back into the bloodstream
It puts back just enough Na+ and K+ and that gets added to the water that wasn’t allowed to leave and it gets returned to circulation
It’s the body’s way of getting its own drink of water from itself 

39. 2nd method of homeostasis our body has to prevent from dehydration
When you get dehydrated, the hypothalamus sends a 2nd message to the pituitary to send a messenger known as ACTH (adrenocorticotropic hormone)
The pituitary sends the messenger ACTH to the adrenal glands that sit on the kidneys to wake up aldosterone
The hormone aldosterone ( a salt hormone) is sent out to help increase the Na+ reabsorption in the kidneys tubule and to send the salt to the blood stream so that now…where there is extra Na+, water follows

40. Hopefully…
With the hormones ADH & Aldosterone, any dehydration can be fixed and the body will resume its normal pattern of having
fluid in the cells 1st
Fluid in the blood and interstitial area 2nd

41. What if another problem occurs….

42. ADH gone wild (part I)!
Heyyy-ooooo!!!!!

43. There are times when the body/brain cannot control ADH
If a patient has a tumor on the pituitary gland, ADH may not be able to be made at all…
This is a serious condition and leads to serious results

44. Fancy word for this condition…
Diabetes Insipidous (D.I.)
NOT DIABETES MELLITUS – inadequate production of insulin causing difficulty in carbohydrate metabolism
Diabetes – a general term for diseases marked by excessive urination
D.I. – polyuria & polydipsia caused by inadequate secretion of ADH from the pituitary

45. Symptoms of ↓ ADH
Now it’s like all you have is DH = diuretic hormone = lots of urine…you need the “A” back
Polyuria
Extreme thirst
Extreme dehydration “Dehydrated Dan”
Hypotension
Tachycardia
Tenting of skin
Pt continues to urinate and urinate and urinate
Specific gravity of < can be as low as 1.005

46. Treatment for D.I.
To return the “A” and give ADH to the body via a drug called vasopressin or Pitressin
Comes in a vial that pt can spray into nose
This helps concentrate urine again

47. ADH gone wild (part II)
What if you had a tumor to the pituitary gland and too much ADH was made?
You would have too much against urination and you would hold fluid…you would have “against urination”
This disease is called SIADH = (↑ADH)
Symptom of inappropriate ADH..it’s inappropriately made…it’s too much

48. Aldosterone
Any time the body has too much fluid on board, it spreads out the Na+ particles in the extracellular spaces. Now the cell appears to be concentrated and the extracellular space looks diluted. This triggers the nervous system to try and help.
Hypothalamus calls to the pituitary to send ACTH to wake up the adrenals to send Aldosterone to the bloodstream
Because aldosterone is salt, when salt reaches the bloodstream, it will now appear that there are many particles in the extracellular space and now the normal cell moves some of its normal amt. of water into the extracellular space to dilute the Na particles. This now causes the cell to shrink and to re-balance things out

49. Symptoms of SIADH Too much fluid Soggy and overloaded “Soggy Sid”
Extremely high HTN
Tachycardia
Specific gravity > more like 1.030
Dark, dark urine
Pt needs a fluid restriction

50. Treatment of SIADH Diuretics such as Lasix (furosemide)
Fluid restriction
Wt QD

51. How much water does the body need?
The amt varies according to:
activity, heat and humidity, age, size, and physical condition

52. We need 1ml for every calorie consumed
If you eat 2100 calories in a day, then you need 2100ml water for that day
It is recommended that we drink ounce glasses of fluid /day.
This is 8 glasses of H20 and at least 5 glasses of other fluids

53. What increases your needs for water
Youth
Fever
Diarrhea
Unusual perspiration
Vomiting
Hemorrhage (loss of blood = loss of fluids)

54. Another balancing mechanism - Acid Base Balance
Fluid and electrolyte balance are not the only things to be maintained in the blood…
The body must maintain acid-base balance by using a buffer system
Your kidneys do this by regulating the hydrogen ions in the body (chemistry)

55. Acids and bases have + and – charges
All organs need these charges, especially the heart, to work
If they become unbalanced, your body knows it and fixes it…sends bicarb out
Your kidneys are responsible to decide which ions to keep and which to excrete out in the urine

56. Normal ph 7 is neutral 1--------------7-------------14
acid neutral base
(acidic) (alkaline)
Blood plasma is

57. Buffer system Helps keep the acid-base balance in line
Example: If too much HCL is removed from the body when vomiting, your kidneys fix the body to balance out the now base solution

58. Conditions that cause dehydration
Heat illness – caused by the excessive perspiration of body fluids with failure to drink sufficient amts of water to replace the lost
There are 4 stages of heat illness…

59. 4 stages of heat illness
Heat fatigue – causes thirst, weakness, fatigue, one should go to a cool place, rest, and drink fluids.
Heat cramp – d/t loss of Na+ and K+, causes leg cramps and thirst, one should go to a cool place , rest and drink fluids

60. 4 stages of heat illness
Heat exhaustion – causes thirst, dizziness, n/v, headache and profuse sweating, one should get into a tub of cool water, 2-3 days of rest and the ingestion of a great deal of water
Heat stroke – involves fever, could produce brain and kidney damage, call 911, put pt in chilled water and go to hospital. Pt can die of heat stroke

61. Excess water intake Can be caused by:
1. CHF, heart pump isn’t working properly, fluid gets all backed up
2. Hypoproteinemia (not enough protein, water 3rd spaces to peritoneal cavity=big belly
3. Some infections
4. Some cancers
5. ↑ ADH = SIADH, Soggy Sid

62. In Review… Our body is very smart
It knows how to balance out problems that occur with water
Osmosis, hypothalamus, pituitary, ADH, aldosterone, and the kidneys is what balances the water in the body

63. Question??????
When one become dehydrated, what happens to the concentration of the extracellular fluid compartment?

64. QUESTION?????
When one can not eliminate fluid from the body but is still consuming more than enough water, What happens to fluid in the extracellular fluid compartment?

65. QUESTION????? Water is lost or gained in what fluid compartment first
2nd space then 1st space to protect the 1st space

66. QUESTION??? What is fluid volume deficit?
What might cause a fluid volume deficit?
What happens to the concentration of solute in the extracellular fluid compartment when one is lacking fluid or in a fluid volume deficit?
What hormones tells the kidneys to conserve what ever water is left?

67. What is this a picture of?

69. THE END The need to replace body fluids is greater
than the need to replace electrolytes.
􀂊 Our thirst mechanism does not match our
hydration state, so it is best to consume
more fluid than thirst dictates.
Replacing Fluid Losses
􀂊 Water intake during prolonged exercise
reduces the risk of dehydration and
optimizes performance.
􀂊 Drinking too much fluid can result in
hyponatremia (low levels of plasma
sodium), which can cause confusion,
disorientation, and seizures