Wk 5 Fluid and Electrolyte Flashcards
1
Q
Body fluid
A
- Transports nutrients & waste to and from cells
- Acts as a solvent for electrolytes & non-electrolytes
- Plays role in maintain body temperature, digestion & elimination, acid-base balance, and lubrication of joints and body tissues
2
Q
What is body fluid?
A
- Fluid -> water that contains dissolved or suspended substances such as glucose, electrolytes, and proteins
~50-60% of adults body weight is WATER
3
Q
Where is water stored
A
Intracellular= inside the cells = 70%
Extracellular= outside the cells = 30%
4
Q
Extracellular space
A
Interstitial fluid– between the cells
Intravascular fluid– plasma (liquid part of the blood)
5
Q
Movement of fluid + electrolytes
A
4 processes:
Diffusion
Facilitated Diffusion
Active transport
Osmosis
6
Q
Osmosis
A
Movement of WATER down a concentration gradient
- From region of low SOLUTE concentration to one of high solute concentration across a SEMIPERMEABLE MEMBRANE
7
Q
Body is trying to maintain homeostasis
A
body trying to balance the solvents and solutes (particles)
8
Q
Osmosis stops when…
A
Stops when concentration differences disappear OR when hydrostatic pressure builds and opposes further movement
9
Q
Osmosis is all about
A
making it balanced with solute concentration by moving solvent (fluid/water)
MOVEMENT OF WATER
10
Q
Diffusion
A
- Movement of molecules from an area of high concentration to a lower concentration
- Movement stops when concentrations are equal in both areas
- MOVEMENT OF MOLECULES
11
Q
Diffusion is all about
A
moving throughout to make the concentration balanced
- like pouring sweetener into coffee, want it well balanced
12
Q
The shifting of water
A
always trying to balance
13
Q
Colloids
A
- Substances that increase colloid osmotic pressure (oncotic pressure)
- MOVE FLUID FROM INTERSTITIAL COMPARTMENT TO PLASMA (blood) COMPARTMENT
14
Q
3 primary colloids
A
albumin, globulin, fibrinogen
15
Q
Oncotic pressure is
A
colloid osmotic pressure
- can be measure with a total protein level (not an indicator of protein nutrition)
16
Q
Colloid oncotic pressures decreases
A
with age and overall malnutrition
- can be replaced with colloid replacements
17
Q
Hydrostatic pressures
A
- Force of fluid in compartment pushing AGAINST A CELL MEMBRANE (or vessel wall)
- Generated by blood pressure
- At capillary level, major force that pushes water OUT of the vascular system into interstitial space
18
Q
Oncotic pressures
A
- Caused by plasma colloids (large molecules) in solution
- Major colloids in vascular system= albumin
- Plasma has LOTS of colloids, interstitial space has little
- Plasma proteins attract water, pulling fluid from tissue space into vascular space
19
Q
Hydrostatic
A
pushes fluid OUT of the capillary
aids into supply of nutrients to the tissues of the body
20
Q
Oncotic
A
pulls fluid INTO the capillary
helps to remove metabolic wastes from the tissues
21
Q
Electrolytes influence
A
Fluid balance, acid base balance, nerve impulses, muscle contraction, heart rhythm, etc.
- change in one changes another
22
Q
Electrolytes
A
Substances that are electrically charged when in solution
Example: K+
23
Q
Concentrations of electrolytes are dependent on:
A
Electrolyte intake
Electrolyte absorption
Electrolyte distribution
Electrolyte excretion
24
Q
Intracellular concentration of electrolytes
A
POTASSIUM +
MAGNESIUM +
PHOSPHOROUS -
25
Extracellular concentration of electrolytes
SODIUM +
CHLORIDE -
BICARBONATE -
CALCIUM +
26
Anion
negatively charged
27
Cation
positively charged
28
Concentration of electrolytes
If an imbalance occurs, we replace abnormal losses with a fluid and electrolyte similar to that which was lost
29
Hyponatremia
= Na < 136 mEq/L
30
Hypernatremia
= Na > 145 mEq/L
31
Water follows sodium
- Main ECF cation
- Governs osmolality
- Influences water distribution
- Aids in acid-base balance
- Activates muscle and nerve cells
- Ion movement important in action potentials
32
Hyponatremia causes
- GI losses -> diarrhea, vomiting, fistulas, NG suction
- Renal losses -> diuretics, adrenal insufficiency
- Skin losses -> burns, wound damage
- Fasting diets, polydipsia (water intoxication)
- Excess hypotonic fluid
33
Sodium can be low because
- person is depleted of water and sodium
- OR person is so diluted they have too much water and not enough sodium
34
Hyponatremia s/s
THINK BRAIN
Confusion/Altered LOC
Anorexia, muscle weakness
Can lead to seizures/coma
CELLULAR SWELLING
35
Dilutional hyponatremia
HYPERvolemic
taking in too much water
- ↑ BP
- ↑ urine Sp. Gravity
- ↑ wt gain
- rapid and bounding pulse
36
Depletional hyponatremia
HYPOvolemic
- ↓ BP, tachy pulse
- ↓ urine sp. gravity
- dry skin
- weight loss
DRY
37
Hyponatremia treatment
- Sodium replacement (SLOWLY!)
- PO/IV
- IV-Normal Saline (0.9%)
+/- diuretic (withhold with depletional hyponatremia)
dilutional hyponatremia = Fluid Restriction
- Treat underlying problem
38
Hypernatremia causes
- IV fluids, tube feeds, near drowning in salt water -> excess sodium intake
- Not enough water intake or too much water loss -> cognitively impaired, diarrhea, high fever, heat stroke
- Profound diuresis
39
Hypernatremia S/S
- Alter LOC/Confusion, seizure, coma
- Extreme thirst (hyperosmolality)
- Dry, sticky mucous membranes
- Muscle cramps
40
Hypernatremia treatment
If H20 loss is cause -> ADD WATER
If sodium excess is cause -> REMOVE SODIUM
41
Hyponatremia GRADUALLY...
- GRADUALLY achieve normal sodium level over a 48 hours period to avoid edema of cerebral cells
- Too quick correction can damage brain cells and be LETHAL!
42
Hypokalemia
K <3.5mEq/L
43
Hyperkalemia
K >5.0 mEq/L
44
Potassium
- Intracellular cation
- Helps regulate cell excitability and electrical status
- Helps control intracellular osmolality
- Diet is main source
- Kidneys main source of potassium loss -> Pee out Potassium
45
Hypokalemia causes
- Renal or GI losses
- DIURESIS
- Acid base disorders (potassium in extracellular space goes into intracellular space)
46
Hypokalemia s/s
Cardiac rhythm disturbances -> can be lethal
Muscle weakness, leg cramps
Decreased bowel motility: constipation, nausea, ileus
47
SERIOUS ADR with UNDILUTED Potassium
- Ventricular fibrillation can be precipitated by administration of undiluted IV KCL.
- Be a good nurse and don’t kill your patient by giving undiluted IV KCL!!!
- NEVER GIVE IV PUSH!!!!!!!!!
- Must be given diluted & administered over a period of time (usually an hour) -> potassium runs (KCL runs)
48
Hyperkalemia causes
- Decreased potassium OUTPUT (renal failure, not peeing)
- Burns, crush injuries, sepsis -> anything with massive cell injury
- Drugs– potassium sparing diuretics, ACE, ARBs NSAIDs
49
Hyperkalemia s/s
- CARDIAC RHYTHM DISTURBANCES
- Muscle weakness, cramps
- Abdominal cramping, diarrhea, vomiting
50
Hyperkalemia treatment
diuretics
sodium polystyrene sulfonate
D50 + insulin
51
Magnesium
Helps to stabilize cardiac muscle cells
Blocks/controls movement of K+ out of cardiac cells
Helps to stabilize smooth muscle
52
Hypomagnesemia
< 1.3 mEq/L
53
Hypermagnesemia
> 2.1 mEq/L
54
Hypomagnesemia causes
diuresis, GI or renal losses, limited intake (fasting or starvation), alcohol abuse, pancreatitis, hyperglycemia
55
Hypomag s/s
hyperactive reflexes, confusion, cramps, tremors, seizures, nystagmus
56
Hypomag treatment
replacement (oral or IV), treat cause
57
Oral replacement
Mylanta
Magnesium sulfate
58
IV replacement
IV Magnesium sulfate
Replace over several days
Can give IV push if necessary
59
Hypermagnesemia causes
increased intake accompanied by renal failure
Chronic renal failure who take milk of magnesium
OB patients for preeclampsia
60
Hypermagnesemia s/s
lethargy, floppiness, muscle weakness, decreased reflexes, flushed/warm skin, decreased pulse/BP
61
Hypermagnesemia treatment
stop replacement
if chronic disease intake -> dialysis
62
Calcium
Hormones released by the thyroid and parathyroid glands are controllers of the amount of calcium that is released from and absorbed into the bone
63
Majority of calcium is
in the bone, ~ 99%
- Stability and strength of bone
- Very small amount, ~ 1%, in cells
- Tiny amount, ~ 0.1%, ionized in extracellular space
- 40% protein bound
- 10% chelated (bound to other substances)
- 50% ionized and available for use
64
Hypocalcemia
< 9.0 mg/dL
65
Hypercalcemia
>10.5 mg/dL
66
What does calcium effect
- Enzyme reactions
- Effects membrane potentials and nerve excitability
Necessary for contraction of skeletal, cardiac and smooth muscle
- Helps in release of hormones, neurotransmitters, and chemical mediators
- Influences cardiac contractility and automaticity
- Necessary for blood clotting (part of the clotting cascade)
67
Hypocalcemia causes
- Unable to mobilize from bone with Hypoparathyroidism or Hypomagnesemia
- Increased renal loss (renal failure)
- Increased binding
- Decreased intake or absorption
- Decreased vitamin D
- Acute pancreatitis
- Thyroid and parathyroid surgery
68
hypocalcemia = increased neuromuscular excitability
Parasthesias (numbness/tingling)
Muscle Cramps
Bone pain
Tetany
Laryngeal spasm
Hyperactive reflexes
69
hypocalcemia = cardiac insufficiency
Prolonged QT interval – can lead to fatal arrhythmia
70
Positive Chvostek’s sign
ipsilateral twitching of the circumoral muscles in response to gentle tapping of the facial nerve just anterior to the ear
71
Positive Trousseau’s sign
carpal spasm upon inflation of a BP cuff to 20 mmHg above the patient's systolic blood pressure for three minutes
72
IV calcium
- Calcium Chloride (ionized form and preferred) -> given through central only at UK
- Calcium Gluconate -> prefer to give through central line
73
Oral calcium
- Elemental calcium, calcium carbonate (Tums)
- May also need Vit D
- Active form in impaired liver &/or kidney function
74
Hypercalcemia causes
hyperparathyroidism, cancers
75
Hypercalcemia s/s
calcium acts like a sedative, fatigue, lethargy, confusion, weakness, leading to seizures, coma
- Kidney stones
76
Hypercalcemia treatment
- Adequate hydration (3-4L a day)
- Increased urine output
- Diuretics and NaCl (sodium excretion is accompanied by calcium excretion)
- Dialysis in renal failure
77
Phosphorous
- Found in bone (85%) and intracellular (14%)
~1% in extracellular space (only small amount in plasma)
- Higher levels in infants and children
- Role in bone formation
78
organic and inorganic phosphorous
Inorganic – circulating and measured
Organic – intracellular
79
Phosphorous essentials
- Essential for ATP formation and enzymes needed for glucose, protein and fat metabolism
- Part of DNA and RNA
- Acid-base buffer
- Normal function of WBCs and platelets
80
Phosphorous and calcium
inverse relationship
- Calcium and phosphate work together
- low serum calcium = high phosphate
81
Hypophosphatemia
< 3.0 mg/dL
82
Hyperphosphatemia
> 4.5 mg/dL
83
Hypophosphatemia causes
- Decreased absorption
- Antacids overdose
- Severe diarrhea
- Increased kidney elimination
- Malnutrition
---- Alcoholism
---- TPN
---- Recovery from malnutrition
84
Hypophosphatemia manifestations
mild-moderate few
Severe:
Tremor
Paresthesia
Confusion to coma
Seizure
Muscle weakness
Joint stiffness
Bone pain
Hemolytic anemia
Platlet dysfunction
Impaired WBC function
85
Hyperphosphatemia Causes
- Kidney failure
- Laxatives/enemas with phosphorus
- Shift from intra- to extracellular compartment
- Massive trauma
- Heat stroke
- Hypoparathyroidism
86
Hyperphosphatemia manifestations
Usually asymptomatic
Typically only symptoms of hypocalcemia:
- Muscle spasms
- Paresthesia
- Tetany
87
Hypophosphatemia treatment
- IV or oral replacement
- Given IV over a LONG period of time
- Increase oral intake
- Take care with CKD or hypercalcemia
- Increased risk of calcifications
88
Hyperphosphatemia treatment
Treat the cause
Calcium-based phosphate binders
Hemodialysis – Renal failure
