Exam 2: Chapter 5 Flashcards
pH range
7.35-7.45
PCO2 range
35-45
HCO3 range
22-26
PO2 range
> 80-100
The total body of water (TBW) for pediatrics is….
70-80% of body weight
Susceptible to significant changes in body fluids
Dehydration in newborns, infants, young children
The total body of water (TBW) for adult men is….
60%
Age-dependent
The total body of water (TBW) for women is…
50%
age-dependent
The total body of water (TBW) for aging adults is…
~50%
Decreased fat and muscle mass
Renal decline
Diminished thirst perception
TBW of intracellular fluid is about
~2/3 (66%) of TBW
fluid within the cell
TBW of Extracellular fluid is about
~1/3 (33%) of TBW
fluid outside of cells
TBW of interstitial fluid is about
~25%
the TBW of blood plasma is about
8%
Hydrostatic pressure pushes water ____ of the capillaries
a. in
b. out
B. out
osmotic/oncotic pressure pulls water ____ the cell
a. in
b. out
a. in
Filtration refers to fluid movement _____of the capillary and _____ the interstitial space
a. out; into
b. into; out
a. out; into
Reabsorption: refers to fluid movement out of the ______________ and into the ______________
a. interstitial space; capillary
b. capillary; interstitial space
c. capillary; tissue
d. tissue; vein
a. interstitial space; capillary
What determines the NET filtration?
the four forces (hydrostatic pressure, osmotic /oncotic pressure, filtration, reabsorption) the net filtration as plasma flows from the arterial end of the capillary to the venous end of the capillary
How does capillary hydrostatic pressure control water movement between compartments?
Facilitates the movement of water from the capillary into the interstitial space
give one example of capillary hydrostatic pressure
Blood pressure
describe how capillary (plasma) oncotic pressure controls water movement between compartments
Attracts water from the interstitial space into the capillary (albumin plays a key role!)
describe how interstitial hydrostatic pressure controls water movement between compartments
Facilitates the inward movement of water from the interstitial space into the capillary
describe how interstitial osmotic/oncotic pressure controls water movement between compartments
Attracts water from the capillary into the interstitial space (albumin plays a key role!)
describe the pathophysiology of edema
Edema occurs when there is a decrease in plasma oncotic pressure, an increase in hydrostatic pressure, an increase in capillary permeability, or a combination of these factors
How does RAA maintain sodium and chloride balance?
RAA decreases circulating blood volume, decreases blood pressure, and decreases plasma concentrations of sodium
Aldosterone secretion is influenced by a number of factors
-↓ circulating BV, ↓ BP, ↓ [plasma sodium]
-Leads to sodium and water reabsorption back into circulation (&
-potassium excretion through the release of renin
-Renin → angiotensin I → angiotensin II (vasocon) → secretion of aldosterone from the adrenal cortex and ADH from the post. pit
How does the natriuretic peptide system maintain a sodium and chloride balance?
Hormones (ANP and BNP) get released when there is an increased volume in the right atrium and it causes sodium and water to get excreted
Hormones primarily produced by the myocardium
-ANP (atrium) & BNP (ventricles)
-Released when ↑ volume in the R atrium (FVO) - like CHF
-Causes sodium and water excretion
How does antidiuretic hormone (ADH) maintain a sodium and chloride balance?
ADH is Produced in the posterior pituitary gland
it is Secreted when plasma osmolality (concentration) increases or circulating blood volume decreases, causing a drop in BP
Triggers osmolarity receptors and thirst and the release of ADH
Increases water reabsorption into the plasma
how do volume-sensitive receptors and baroceptors maintain a sodium and chloride balance?
Sense a decrease in systemic blood volume, resulting in low BP
Nerve endings that stimulate thirst and ADH
Volume sensitive-receptors are located in the right and left atrium and thoracic vessels
Baroreceptors are located in the aorta, pulmonary arteries, and carotid arteries
A normal sodium range is
135-145
A normal potassium range is
3.5-5.0
Isotonic fluids ___________ SELECT ALL THAT APPLY
a. Will pull a less concentrated solution into itself
b. Shift and flow into a more concentrated solution
c. stay inside the bloodstream or intravascular compartments
D. Occur when total body water (TBW) changes is proportional to electrolyte change (no change in concentration)
C. stay inside the bloodstream or intravascular compartments
D. Occur when total body water (TBW) changes is proportional to electrolyte change (no change in concentration)
give examples of isotonic fluids
0.9%, LR (contains Na+, CL-, K+, and Ca+)
how do Hypertonic fluids work?
It pulls less concentrated solution into itself
water moves from the ICF to ECF
What is the most common reason for needing to use hypertonic fluids?
Hyponatremia or deficit in ECF water (dehydration)
another way to say it:
sodium gain or water loss “intracellular dehydration”
Hypertonic fluids draw fluid ____of the cell and ____the blood
a. out; into
b. into; out
A. out; into
which of the following solutions can cause cell shrinkage?
a. isotonic
b. hypertonic
c. hypotonic
d. D5W
b. Hypertonic
Hypotonic solutions work by
Shift and flow into a more concentrated solution
Draw fluid from vessels and move fluid into the cells
what is the most common causes of hypotonic alteration (too much water, not enough sodium)
sodium deficit or free water excess
Hypotonic alterations
Decrease in ECF sodium (Na+) concentration (hyponatremia) results in ICF osmotic attraction of water with swelling and potential bursting of cells.
give examples of hypotonic fluids
D5W, 0.45% NS
What are some clinical manifestations of hyponatremia?
*Neurologic changes as water shifts into the cells: Lethargy, headache, confusion, decreased reflexes, seizures, and coma (due to impaired nerve conduction)
*Most life-threatening: cerebral edema and increased intracranial pressure
Hyponatremia:
Movement of ECF into the cells causes ______ SELECT ALL THAT APPLY
A. hypovolemia
B. hypotension
C. tachycardia,
D. decreased urine output
E. hypervolemia
F. hypertension
A. hypovolemia
B. hypotension
C. tachycardia
D. decreased urine output
What are some causes of hyponatremia?
-Pure sodium loss
-Low intake
-Mediations (diuretics)
-Dilutional hyponatremia–> too much free water
Sodium excess in hypernatremia causes plasma hyperosmolality and cell shrinking
a. True
b. false
a. true
list some common causes of hypernatremia
○ Inadequate water intake
○ Excessive oral salt intake
○ Excessive sweating, fever
○ Loss of fluids: vomiting, diarrhea, burns
○ Infusion of hypertonic saline
Some medications
list clinical manifestations of hypernatremia
Restless, agitated, confused (and other CNS symptoms), thirst, dry mucous membranes, edema, increased BP, weight gain.
clinical manifestations of hyperkalemia
Mild
*Increased neuromuscular irritability
o Muscle cramps
o Abdominal cramping, and diarrhea
Severe
*Decreases the resting membrane potential
o Muscle weakness, loss of muscle tone, and flaccid paralysis
oCV: dysrhythmias, bradycardia, heart block, cardiac arrest
Hyperkalemia can be caused by
○ Increased oral or IV intake
○ Shift of K+ from ICF into ECF
○ Decreased renal excretion
○ Insulin deficiency
○ Cell trauma that results in lysis (cell contents are dispersed into ECF)
○ Transfusion of old RBCs (many cells have died and the infusion is high in K+)
Hypokalemia can be caused by
Reduced intake of potassium
Increased entry of potassium into cells (during alkalosis as hydrogen ion leaves the cell and K+ goes into the cell)
Increased loss of potassium (vomiting, NG suctioning)
list Hypokalemia manifestations
Manifestations (depend on the rate of decrease and severity)
*Results in membrane hyperpolarization cause a decrease in neuromuscular excitability
o skeletal muscle weakness, fatigue
o smooth muscle loss of tone/motility (N/V, constipation, ileus)
o cardiac arrhythmias
In caring for a client with a laboratory result of Na+ = 149, which would likely be the priority intervention?
A. Restriction of fluids
B. Administration of a diuretic
C. Administration of Isotonic 0.9% normal saline fluid
D. Administration of Isotonic salt-free fluid (5% dextrose in water)
D. Administration of Isotonic salt-free fluid (5% dextrose in water)
The RN is reviewing a client’s laboratory results and notes a K+ level of 5.9 mEq/L. Which nursing action should be initiated immediately?
A. Initiate seizure precautions
B. Initiate cardiac monitoring
C. Institute hourly neuro checks
D. Administer oxygen via facemask
B. Initiate cardiac monitoring
The sum of all fluids within body compartments =
A. intracellular fluid (ICF)
B. Interstitial fluid
C. extracellular fluid (ECF)
D. total body water
D. Total body water
Intracellular fluids contain larger amounts of __________; while extracellular fluids contain larger amounts of __________.
A. potassium; sodium and chloride
B. sodium and chloride; potassium
A. potassium; sodium and chloride
If left untreated, patients with severe ____________ can develop altered mental status, seizures, and even coma due to cellular swelling of brain cells/ cerebral edema.
A. hypernatremia
B. hypokalemia
C. hyperkalemia
D. hyponatremia
D. Hyponatremia
Intracellular body fluid comprises a(s) __________ proportion of total body fluid than extracellular body fluid.
A. equal
B. smaller
C. larger
C. larger
__________ refers to fluid movement out of the capillary and into the interstitial space; while __________ refers to fluid movement into the capillary from the interstitial space.
A. Filtration; reabsorption
B. Reabsorption, filtration
A. Filtration; reabsorption
Capillary hydrostatic pressure is otherwise known as ____________.
A. capillary oncotic pressure
B. interstitial hydrostatic pressure
C. interstitial oncotic pressure
D. blood pressure
D. Blood pressure
________, a class of water channel proteins that are permeable to water allows water to move freely by diffusion.
A. Albumin
B. Aquaporins
C. Lymphatics
B. Aquaporins
Fluid accumulation within a body cavity is known as __________.
A. local edema
B. dependent edema
C. generalized edema
D. effusion
D. effusion
Water balance is regulated primarily by ____________, also known as vasopressin.
A. adosterone
B. Chloride
C. antidiuretic hormone (ADH)
D. renin
C. antidiuretic hormone (ADH)
What is the arterial blood gas mnemonic?
Respiratory
Opposite
Alkalosis ↑ pH, ↓ pCO2
Acidosis ↓ pH, ↑ pCO2
Metabolic
Equal
Acidosis ↓ pH, ↓ pHCO3
Alkalosis ↑ pH, ↑ pHCO3
define total body of water
the sum of all fluids within all body compartments
list the starling forces
Occurs as a result of changes in:
Hydrostatic pressure
Osmotic/oncotic pressure
Filtration
Reabsorption
which forces favor filtration?
Blood hydrostatic pressure (BP)
Interstitial osmotic/oncotic pressure (water-pulling out of vessel)
which forces favor reabsorption
Blood osmotic/oncotic pressure (water-pulling into vessel)
Interstitial hydrostatic pressure
what can affect the net filtration rate?
Abnormal changes in either NET hydrostatic pressure or NET osmotic pressure (albumin/protein levels) will affect the NET filtration rate
describe what happens in hypovolemia, give examples of what can cause it and how to treat it
Isotonic fluid loss
through v/d, hemorrhage, severe wound draining, excessive sweating
Tx: isotonic fluids (.9% NS, LR)
describe what happens during hypervolemia, give examples of what can cause it and the treatment
Isotonic fluid excess
Excess IVF admin, hypersecretion aldosterone, certain drugs (cortisone- causes renal reabsorption of NA and H2O)
Tx: Lasix (furosemide)
what are the clinical manifestations associated with hypertonic alterations (loss of more water than sodium)?
thirst, weight gain, bounding pulses, increased BP, Muscle twitching, hyperreflexia, confusion, coma, seizure, and cerebral hemorrhage
what are some examples of hypertonic fluids?
3% NS, 5%NS
