Unit one and Two Flashcards
(153 cards)
1
Q
Normal Sodium Levels
A
135-145 MEq/L
2
Q
Critical values for sodium
A
less than 120 or greater than 160 mEq/L
3
Q
Where is sodium normally found?
A
main cation of the ECF
4
Q
How does sodium move in the body
A
active transport
5
Q
What hormones influence sodium
A
aldosterone and antidiuretic hormone
6
Q
what is the primary source of sodium
A
diet
7
Q
What are the most dangerous problems with sodium imbalances
A
cerebral dehydration and seizure
8
Q
Serum levels for Hyponaturemia
A
less than 135mEq/L
9
Q
causes of Hyponatremia
A
vomiting Nasogastric suctioning diarrhea excessive diaphoresis wound drainage medication renal disease
10
Q
Serum levels for hypernaturemia
A
greater than 146 mEq/L
11
Q
Common cause of sodium gain
A
excessive sodium intake
inability to ingest water
hypertonic tube feeding w/o hypertonic IV fluids
12
Q
Consequences of sodium retention
A
Hyperaldosteronism
Cushing’s syndrome
Corticosteroids
acute renal failure
13
Q
Common assessment of sodium imbalances
A
confusion, coma, seizures, orthostatic hypotension, muscle weakness,
14
Q
Common assessment findings of hyponatremia
A
headache, fatigue, apathy, respiratory distress, anorexia, weight loss, nausea, vomiting, abdominal cramps
15
Q
Common assessment findings of hypernatremia
A
restlessness, irritability, lethargy, dyspnea, tachycardia, dry mucous membranes, dehydration, flushed skin, low urine output
16
Q
How much of an adult body mass is water?
A
50-60% weight in adults
17
Q
What affects water content
A
gender (greater in males), body mass( more fat, less water), age
18
Q
How much water is in the ICF
A
2/3
19
Q
what is interstitial fluid
A
fluid in spaces between cells
20
Q
what is plasma
A
liquid part of blood
21
Q
Transcellular fluid
A
small amount of fluid contained within specialized cavities of the body- CFS, GI tract, pleural
22
Q
what are electrolytes
A
substances that when dissolved in water separate into charged particle
23
Q
What are the cations in the body
A
sodium, potassium, calcium, magnesium
24
Q
what are the anions of the body
A
chloride, phosphate, bicarbonate
25
What are the major functions of electrolytes
regulate water distribution, muscle contraction, nerve impulse transmission, blood clotting, regulate enzyme reactions, regulate acid-base balance
26
How does ICF and ECF transportation occurs
```
filtration
diffusion
facilitated diffusion
osmosis
active transport
```
27
Diffusion
passive movement of particles across a permeable membrane from a higher concentration to a lower concentration
28
Example of diffusion
gas exchange in the alveoli
29
Facilitated Diffusion
movement of specific particles across a cell membrane by a protein carrier
passive
30
Examples of facilitated diffusion
glucose and amino acids entering or leaving the cell
31
Active Transport
movement of particles across a cell membrane from areas of low concentration to areas of higher concentration by combining with a carrier on the outside of the cell membrane and moving the inside of cells
requires energy
32
Example of active transport
sodium/potassium pump
33
Normal potassium values
3.5-5.0 mEq/L
34
critical value of potassium
2.5-6.5 mEq/L
35
Role of potassium
significant role in cardiac muscle, skeletal muscle and smooth muscle activity
36
How does potassium move
active transport with sodium-potassium pump
37
What hormone enhances kidney excretion of potassium
aldoserone
38
what is the primary source of potassium
diet
39
causes of Hypokalemia (less than 3.5)
```
vomiting
prolonged gasrtic suctioning
chronic diarrhea
eating disorders
hemorrhage
medication
```
40
causes of hyperkalemia (greater than 5.5)
```
acute renal failure
chronic kidney disease
glomerulonephritis
addison's disease
medication
excessive of potassium intake
```
41
What is calcium
the most abundant mineral in human body
42
where is calcium found
99% in bones and teeth
| 1% in blood stream in bound form and ionized form
43
What is ionized calcium
is the active form of calcium and must be maintained in a narrow range
44
what is calcium bound to
serum proteins, especially albumin
45
where does calcium get absorped
in the intestines and requires active form of vitamin D
46
What is calcium required for
transmission of nerve impulses, cardiac muscle contractility
clotting mechanism
teeth and bone formation
47
Hypocalcemia serum levels
total- < 8.5mg/dl
| ionized- < 4.9 mg/dl
48
what causes hypocalcemia
```
any condition that decreases the production of parathyroid hormone
surgical removal or injury
pancretitis
multiple blood transfusion
laxative abuse
```
49
what happens when serum calcium levels is low?
calcium is borrowed from the bones
50
Why can pancreatitis cause hypocalcemia
lipolysis produces fatty acid that combine with calcium ions decreasing serum calcium levels
51
Why does multiple blood transfusions cause hypocalcemia
the citrate use to anticoaguleate blood binds with the calcium
52
Consequence of hypocalcemia
increased nerve excitability and sustained muscle contraction- tetany
- due to decreased calcium level, decreases threshold levels
53
Consequence of Hypocalcemia
```
Chvostek
Trousseau
Laryngeal strigor
Dysphagia
numbness and tingling around mouth
```
54
Chvostek sign
twitching of the lip and muscles on the side of the face stimulated from a tap over the facial nerve in front of the ear
(cranial nerve VII)
55
Trousseas sign
carpel spasms produced by inflating a blood pressure cuff on the arm
56
Treatment of hypocalcemia
oral/ IV replacement (calcium gluconate or calcium chloride)
Vitamin D
Aluminum hydroxide gel- hyperphosphatemia
Mg for Hypomagnesemia
57
Hypercalcemia serum levels
> 10.5 mg/dL- total
| > 5.0 mg/dL - ionized
58
Critical calcium values
12 mg/dL
59
Causes of hypercalcemia
```
excess intake
loss from bones, increased mobilization from bones
steroid therapy
hyperthyroid
Metastatic Cancer
```
60
Treatment of hypercalcemia
volume expansion with NS
loop diuretics or corticosteroids
calcitonin and/or mithramycin (prevent bone reabsorption
61
Phosphorus serum levels
2.5-4.5 mg/dL
62
what does phosphorus assist with
muscle contraction, maintaining heart rhythm, kidney function, nerve conduction, acid-base balance, functioning of RBC
metabolism of protein, fat and carbs
63
Phosphorus is a major component of what
ATP, DNA, RNA
64
where is most of the phosphorus found
85% bound to teeth and bones
| rest in cells
65
what regulates phosphorus
parathyroid hormone
66
What are phosphorus levels related to
glucose intake, insulin administration, hyperventalation
67
Hypophosphatemia serum levels
< 2.4mg/dL
68
causes of hypophosphatemia
```
malabsorption syndrome
recovery from malnutrition or refeeding syndrome
glucose or insulin therapy
TPN
alcohol withdraw
phosphate-binding antacids
respiratory alkalosis
```
69
serum levels of hyperphosphatemia
level greater than 4.4 mg/dL
70
causes of hyperphosphatemia
```
chemotherapy for leukemia or lymphoma
excessive milk injetion
excessive use of phosphate containing laxative or enemas
vitamin D excess
chronic kidney disease
acute renal failure
hypoparathyroidism
sickle cell anemia
```
71
Normal magnesium serum levels
1.6-2.6 mg/dL
72
what is the major role of magnesium
```
major role in 300 fundamental enzymatic reactions
powers the sodium-potassium pump
aids converting ATP to ADP
transmits electrical impulses
important in skeletal muscle relaxation
maintains heart rate
Necessary for release of PTH
```
73
Hypomagnesemia serum level
1.5 mEq/L
74
Hypomagnesemia causes
nutritional or metabolic abnormalities
fluid loss form GI tract
redistribution of body magnesium
75
What inhibits magnesium absorption
phytates
oxalates
fat
76
Assessment findings of hypomagnesemia
```
similar to hypocalcemia or hypokalemia
muscle twitching
tremors
hyperreactive reflexes
mood changes
nausea, vomiting, diarrhea
seizures, hallucinations
```
77
What is SIADH
syndrome of inappropriate antidiuretic hormone
| results in water intoxication and hyponatremia
78
characteristics of SIADH
```
fluid retention
serum hypoosmolality
dilutional hyponatremia
hypochloremia
concentrated urine
common in elderly
```
79
causes of SIADH
Malignant tumor
central nervous system disorders
drug therapy
miscellaneous condition
80
Signs and Symptoms of SIADH
```
clinical signs and symptoms related to hypovolemia dn hyponatremia are present as mild to severe
low urine output
dark concentrated urine
thirst
dulled sensorium
dyspnea
hypertension
```
81
Osmosis
a process by which molecules of solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus equalizing the concentrations on each side of the membrane
82
Osmolality
concentration of solute per kilogram of water
83
Osmolarity
concentration of solutes per liter of solution
84
Serum osmolality
measures the body's water balance
85
Normal values of osmolality
275-295 mOsm/Kg
86
Water deficit osmolality
value higher than 295 mOsm/kg- concentration of particles is too great or the water is too low
87
Water excess osmolality
values lower than 275 mOsm/kg- too little solute for the amount of water or too much water for the amount of solute
88
Conditions that increase serum osmolality-
dehydration/sepsis/fever/ sweating burns
Diabetes mellitus
Diabetes Insipidus
Uremia
Hypernatremia
Ethanol, methonal or ethylene glycol ingestion
mannitol therapy
89
Conditions that increase urine osmolaity
```
dehydration
SIADH
adrenal insufficiency
glycosuria
Hypernatremia
High protein diet
```
90
Conditions that decrease serum osmolality
excess hydration
hyponatremia
SIADH
91
Conditions that decrease urine osmolality
diabetes insipidus
Excess fluid intake
acute renal insufficiency
glomerulonephritus
92
Tonicity
refers to the osmolality of a solution
93
Isotonic solution
fluids with the same osmolality of the cell interior. Remains in the vascular compartment
expanding vascular volume
Normal Saline 0.9%
94
Hypertonic Solutions
fluids with solutes more concentrated than in the cell (increased osmolality)
causes a shift from cells into the vascular space, expanding vascular volume
- 3% Normal Saline
95
Hypotonic Solution
solutes are less concentrated than in the cell. Helps to move cellular dehydration through shifting out of blood vessels into the cells promotes elimination by kidneys
0.45% normal saline
96
Oncotic Pressure
Pressure caused by plasma colloids in a solution
protein is the major colloid in the vascular system
plasma proteins attract water pulls from tissue to vascular space
97
What is the capillary fluid movement determined by?
Capillary Hydrostatic Pressure
Plasma Oncotic pressure
Interstitial hydrostatic pressure
Interstitial oncotic pressure
98
Which pressures move water out of the capillaries
capillary hydrostatic pressure and interstitial oncotic pressure
99
Which pressures moves fluid into the capillaries
Plasma oncotic pressure and interstitial hydrostatic pressure
100
Distribution of water
| First spacing
normal distribution in ICF and ECF
101
Distribution of water
| Second Spacing
Abnormal accumulation of interstitial fluid
102
Distribution of Water
| Third Spacing
accumulation of fluid in a part of the body where it cannot be use- fluid is trapped
103
what controls the body's water balance
Needs access to water
Normal thirst and ADH mechanism
Normal functioning kidneys
104
What is the primary protection of hyperosmolality
the thirst mechanism
105
How is the thirst mechanism stimulated
Stimulated by fluid loses or increases by thirst receptors in the hypothalamus
stimulates ADH and aldosterone release
106
Where are glucocorticoids and mineralcorticoids secreted?
by the adrenal cortex
107
What is the function of glucocorticoids and mineralcorticoids
regulate water and electrolytes
108
function of glucocorticoids (cortisol)
anti-inflammatory effect and increase serum glucose levels
| response to physical stress
109
Function of Mineralcorticoidis (aldosterone)
enhance sodium retention and potassium excretion
110
What triggers aldosterone release?
drop in blood pressure or blood volume
111
action of aldosterone
causes kidneys to reabsorb more sodium into the blood increasing serum sodium levels- water follows
- lowers serum potassium levels
112
Atrial Natriurtic Peptide (ANP)
| Characteristic
Cardiac Hormone found in the atria
| released by high blood volume and high blood pressure
113
How does ANP lower blood pressure
causes vasodilation and suppressing the RAAS
decreases ADH
Increases GFR
114
Brain Natriuretic Peptide characteristics
cardiac hormone, within the ventricles released with increased blood volume and pressure when ventricles are stretched
115
How do BNP decrease blood volume and pressure
vasodilation of Arteries and veins
Decrease release of aldosterone
Diuresis- resulting in excretion of both sodium and water
116
What causes fluid deficit?
```
diarrhea
fistula drainage
hemorrhage
Polyuria
inadequate intake
```
117
What is the goal of treatment for fluid volume deficit
correct cause
replace water and electrolytes
IV fluids 0.9 NS or LR
Blood
118
How is SIADH diagnosed
low urine output
high specific gravity
sudden weight gain without edema
decreased serum sodium level
119
What is the treatment of SIADH
Treatment of underlying cause
Fluid restriction
gradual weight loss
progressive rise in serum sodium concentration and osmolality, symptom improvement
head of bed flat or no more than 10 degrees- enhance venous return
120
What results in an over production of ADH
Syndrome of inappropriate antidiuretic hormone
121
what results in an underproduction of ADH
diabetes insipidus
122
What is the osmolarity of patients with SIADH
lows osmolarity
123
What are the characteristics of SIADH
fluid retention, serum hypoosmolality, dilutional hyponatremia, hypochloremia, concentrated urine in the presence of normal or increased intravascular volume and normal renal function
124
what population is SIADH more common?
older adults
125
what are the Causes of SIADH
malignant tumors, drug therapy, CNS disorders, hypothyroidism, lung infection, COPD
126
what are the affects of ADH
increase the permeability of renal distal tubule and collecting duct- leads to reabsorption of water , ECF volume increases, GFR increases, sodium levels decline
127
how is the diagnosis of SIADH made
by the simultaneous measurements of urine and serum osmolality
128
what should a nurse look for in patients at risk for SIADH?
low urine output with high specific gravity
sudden weight gain without edema
decreased serum sodium levels
Monitor I&O, vital signs, heart and lung sounds
signs of hyponatremia
129
What is the treatment of SIADH
- avoid medications that stimulate ADH release
fluid restriction
position the head of bed flat or elevated 10 degrees
130
why would you position the bed of a patient with SIADH at 10 degrees or flat?
because it enhances venous return to the heart and increase left atrial filling pressure, thereby reducing the release of ADH
131
what is the fluid restriction of a patient with chronic SIADH
800-100 mL of water daily
132
What medication is often given to patients with chronic SIADH
Demeclocycline
133
what are the actions of demeclocycline
blocks the effects of ADH on the renal tubules resulting in more dilute urine
134
What causes diabetes insipidus(DI)?
caused by a deficiency of production or secretion of ADH or decreased response to ADH
135
what is the most common cause of DI?
central DI
136
What is the etiology of central DI
results from an interference with ADH synthesis, transport or release
-brain tumor, head injury
137
what is the etiology of nephrogenic DI
results from inadequate renal response to ADH despite presence of adequate ADH
138
primary DI
results from excessive water intake
139
what are the clinical manifestation of DI
polyuria and polydipsia
140
what are the phases of onset for central DI
acute phase- polyuria
interphase- urine volume normalize
third phase- central DI is permanent- 10-14 days after surgery
141
what is the nursing management of DI
early detection
maintenance of adequate hydration
patient teaching
142
what is the treatment of central DI
fluid and hormone therapy
| - IV hypotonic saline or dextrose 5%
143
What is the treatment of nephrogentic DI
dietary measures and thiazide diuretics, and in some cases taking indomethacin (NSIAD that increases sensitivity to ADH)
144
When does hypovolemic shock occur?
after a loss of intravascular fluid volume
145
what is absolute hypovolemia
results when fluid is lost through hemorrhage, gastrointestinal loss, fistula drainage, diabetes insipidus, or diuresis
146
what is relative hypovolemia
fluid volume moves out of the vascular space into extravascular space (third spacing) burns.
147
what is a consequence of decreased intravascular volume
```
decreased venous return
decreased preload
decreased stroke volume
decreased CO
decreased tissue perfusion and impaired cellular metabolism
```
148
What is the clinical presentation of hypovolemic shock?
```
tachypnea -> bradypnea
decreased urine output
pallor, cool clammy skin
Decreased cerebral perfusion (anxiety, confusion, agitation)
Absent bowel sounds
```
149
Diagnostic lab findings of hypovolemic shock
```
hematocrit
hemoglobin
lactate
urine specific gravity
changes in electrolytes
```
150
How much fluid may a patient compensate for?
up to 15% of total blood volume
151
A loss of 15-30% of total blood loss results in what?
sympathetic nervous system mediated response
152
What happens in a sympathetic nervous system mediated response?
increased HR
Increased CO
Increased respiratory rate and depth
The stroke volume, central venous pressure is decreased
153
How is hypovolemia corrected?
by crystalloid fluid replacement
