Ch.10 Fluid/Electrolytes Flashcards
Acidosis
an acid-base imbalance characterized by an increase in H+ concentration
Active transport
physiologic pump that uses energy to move fluid or electrolytes from one region to another
Alkalosis
an acid-base imbalance is characterized by a reduction in H+ concentration or an increase in bicarbonate concentration
Colloid
A fluid containing particles that are nonsoluable and evenly distributed throughout the solution
ALBUMIN
Colloid oncotic pressure
osmotic pressure created by the protein in the bloodstream
Crystalloid
a fluid containing soluble MINERAL IONS and water in a solution
Diffusion
the process by which solutes move from an area of higher concentration to one of lower concentration; does not require expenditure of energy
Homeostasis
maintenance of constant internal equilibrium in a biologic system
Hydrostatic pressure
the pressure created by the weight of fluid against the walls that contain it
Hypertonic solution
a solution with an osmolality higher than that of serum
Hypotonic solution
a solution with an osmolality lower than that of serum
isotonic solution
a solution with the same osmolality as blood
Osmolality
the number of milliosmoles per kilogram of solvent; espressed as milliosmoles per kilogram
osmolarity
the number of milliosmoles per liter of solution; expressed as milliosmoles per liter; describes the concentration of solutes or dissolved particles
Osmosis
the process by which fluid moves across a semipermeable membrane from an area of low solute concentration to an area of high solute concentration; process continues until equal concentrations
Tonicity
ability of solutes to cause an osmotic driving force that promotes water movement from one compartment to another
*most commonly refers to NaCl content of solution & how to compares to the physiologic fluid
A solution is a mixture of
SOLVENT, fluid medium and SOLUTES, which are particles
Plasma is composed of _____water and contains what solutes?
Plasma is 92% water + proteins, glucose, lipoproteins, and mineral ions (electrolytes)
an adult’s weight is how much fluid?
60%
What 2 compartments is body fluid located?
40% or 2/3’s in Intracellular space (in cells)
20% or 1/3 in Extracellular space (outside of cells)
*The extracellular compartment is further divided into what and %
3L -Intravascular (fluid within blood vessel)
11-12L - Interstitial (fluid surrounding cells/LYMPH)
1L - transcellular (outside epithelial membrane)
What is the fluid in the intravascular space?
plasma, which is 3 L of 6L of blood volume
What are examples of transcellular fluids?
cerebrospinal, pericardial, synovial, intraocular, pleural fluids, sweat, digestive secretions
What is third spacing?
Fluid is lost into a space in the body that does not contribute to equilibrium.
Accumulates within membrane-bound spaces such as the peritoneal cavity and pleural space
Examples of third space fluid conditions
Ascites - fluid build up in abdomen
Pleural effusion - fluid in lungs
pericardial effusion - fluid around heart
angioedema - fluid/swelling under skin
What is early evidence of third-space fluid shift?
^HR, decreased bp, decreased central venous pressure, edema, ^body weight.
Decrease in urine output despite adequate fluid intake. /
*kidneys receive less blood and attempt to compensate by decreasing urine
Cation
Anion
Cation - positive charge
Anion - negative charge
What are the major cations?
Sodium
Potassium
Calcium
Magnesium
Hydrogen ions
What are the major anions?
Chloride
Bicarbonate
Phosphate
sulfate
Negatively charged protein ions
Electrolyte concentration is expressed in
mEq - milliequivalents per liter, a measure of chemical activity
*mEq - being equivalent to the electrochemical activity of 1 mg of hydrogen.
What is the major electrolyte in ICF and ECF?
How does the body maintain these 2 electrolytes?
ICF - potassium
ECF - sodium
*Sodium potassium pump
Hydrostatic pressure pushes fluids
Osmotic pressure pushed
Hydrostatic - pushes fluids OUT toward ICF
Osmotic - pulls fluid INTO capillary from ICF
Crystalloid or colloid solutions can be used to temp replace blood or replenish fluid loss. What are examples of crystalloid solutions?
What are examples of colloid solutions?
CRYSTALLOID - replace fluids
Normal saline
half normal saline
Lactated ringers solution
COLLOID - temp blood replacement
Albumin
hyper oncotic starch
dextran
The tonicity of a solution can be used to
*refers to the _____content of solution
Physiologic fluid is ________
drive water movement between compartments to change the state of cellular hydration and cell size
*refers to NaCl content of the solution
**Physiologic fluid is 0.9% NaCl
Isotonic solution?
Isotonic solutions are 0.9% Nacl- same as bloodstream. Do not provoke water movement, just expand plasma volume of blood
Hypotonic solution
Used for
Composed of less sodium chloride compared to blood.
Less solute but more water than the bloodstream.
Used to move water from ECF into ICF. Used to hydrate
Hypertonic solutions
Used to treat
Composed of a greater concentration of NaCl compared to blood
*Contains more solute and less water than blood /Pulls water from ICF to ECF =dehydration of cells
Used for disorders of severe edema, cerebral edema
(Sodium, glucose, mannitol)
Sodium potassium pump is powered by
Performs ______transport
Powered by enzyme Na+K+ ATPase
Performs active transport
What are organs of fluid loss
Kidneys
Skin
Lungs
GI tract
In healthy adults, normal serum osmolality is
275 to 290 mOsm/kg
Serum osmolality primarily reflects
Urine osmolality reflects
Serum - concentration of sodium
Urine - urea, creatinine and uric acid
What is BUN and what is normal range
BUN - lab value that measures amount of urea in blood stream
10-20 mg/dL
*can be increased in GI bleed, fever, sepsis
*can decrease in end-stage liver disease, low protein diet, starvation
What is creatinine and what is normal level
Breakdown product of muscle metabolism - better indicator of renal funcation than BUN
Normal - 0.7-1.4mg/dL
*increases when renal function decreases
Hematocrit measures
Normal values
Conditions that increase
Conditions that decrease
The % of red blood cells in the volume of whole blood
*ranges from 42%-52% in men and 35%-47% in women
-Dehydration and polycythemia can increase
-Overhydration & anemia can decrease
Urine-specific gravity measures
*normal range
the density of urine compared to water
**measure the concentration of solutes in urine
*one way to assess the kidney’s ability to excrete or conserve water
**1.005-1.030
1.005 is very higher in water content
1.030 is very concentrated
What are the organs involved in homeostasis?
Kidneys, heart, lungs, pituitary gland, adrenal gland, parathyroid glands
The kidneys filter how much plasma every day?
180 L of plasma
Major functions of the kidneys in maintaining normal fluid balance include:
-Reg of ECF volume & Osmolality by selective retention and excretion
-Reg of electrolyte levels in ECF
-Reg of PH in ECF
-Excretion of metabolic waste and toxins
Major functions of the kidneys in maintaining normal fluid balance include:
-Reg of ECF volume & Osmolality by selective retention and excretion
-Reg of electrolyte levels in ECF
-Reg of PH in ECF
-Excretion of metabolic waste and toxins
The hypothalamus manufactures ADH which is stored and used for?
- Stored in posterior pituitary gland
- Released as needed to conserve water - acts on nephrons (causes increased reabsorption of water from tubules into bloodstream)
Increased secretion of aldosterone causes?
Sodium retention (thus water retention) and potassium loss
What is the function of the parathyroid glands?
regulate calcium and phosphate balance by means of PTH
PTH influences reabsorption of calcium from bones into the bloodstream, calcium absoprtion from intestine and from renal tubules
What is Renini-Angiotensin-Aldosterone system
When kidneys sense low pressue they secrete Renin from juxta which triggers RAAS
Renin converts angiotensinogen into angiotensin I which ACE converts into II. II stimulates peripheral vasoconstriction which ^BP. II also stims adrenal gland to secrete aldosterone = increase absorption sodium/water
Function of Osmoreceptors?
Located on hypothalamus
Sense change in sodium concentration
Talks to pituitary to release ADH to increase reabsoprtion
Function of Natriuretic peptides
Stimulated by stretching of heart: (high bp/volume)
Inhibit aldosterone
Inhibit renin and RAAS
-Natriuresis(excrete sodium)
-vasodilation
*decrease water and sodium in circulatory = decreased bp ///direct opposite of RAAS
Define HYPOVOLEMIA
when loss of ECF volumes exceeds the intake
-abnormal fluid losses (diarrhea, vomiting, gi suctioning, sweating, decreased intake, third-space shifts. Diabetes, adrenal insufficiency, osmotic diuresis, hemorrhage and coma
Define HYPOVOLEMIA
when the loss of ECF volumes exceeds the intake
-abnormal fluid losses (diarrhea, vomiting, gi suctioning, sweating, decreased intake, third-space shifts, burns, Diabetes, adrenal insufficiency, osmotic diuresis, hemorrhage and coma
Signs and labs for hypovolemia
-Concentrated urine, cap refill prolonged, decreased BP, flattened neck veins, dizzy, weak, thirst, confusion, increased pulse, muscle cramps, sunken eyes, increased temp, cool, clammy pale skin
^Hg,^hct, ^serum and urine osmolality, decreased urine sodium, ^ BUN and creatinine
Signs and labs for hypervolemia
acute weight gain, edema, distended jugular veins, crackles, sob, ^bp, bounding pulse, ^RR, ^urine output
Lab- decreased BUN & hematocrit
*aldosterone is constantly stimulates
Hypervolemia refers to
Expansion of the ECF by abnormal retention of water and sodium
SODIUM
Most abundant where?
Range
Role
Regulated by
affects body?
-Most abundant in ECF
-135-145 mEq/L
-Primary determinant of ECF volume and osmolality / Controlling water distrub in body
-Reg by ADH, thirst, RAAS
-Muscle contraction and transmission of nerve impulses
What is intravascular fluid
fluid inside the blood vessles
contains plamsa
What is interstitial fluid
Fluid that surrounds the cells
*Lymph
What is transcellular fluid?
cerebrospinal fluid, pericardial, synovial, intraocular, pleural, sweat, digestive fluids
How do lungs maintain fluid homeostasis?
remove approx. 300ml of water
acid/base balance
Where is aldosterone secreted from?
Adrenal cortex
Cortisol produced in large quantities can cause?
sodium and fluid retention
ADH is manufactured where?
Hypothalamus
ADH is released for
in reaction to dehydration or blood loss
tells kidneys to retain water
What does the parathyroid gland regulate?
calcium & phosphate
What is PTH
Parathyroid hormone - influences reabsorption of calcium from bones, intestine and renal tubules into the bloodstream
Where are the baroreceptors? and function
left atrium, carotid and aortic arches
respond to changes in circulating blood volume
reg para and sympthatetic, endocrine activity
Where is 98% of the bodies potassium?
inside the cells
WHat does potassium influence?
both skeletal and cardiac muscle activity
What alkalosis is present what does potassium do?
temp shift into the cells
What are 3 medications that can lead to hypokalemia?
corticosteriods
sodium penicillin
amphotericin B
Potassium deficit is related to stomach how
large amounts are in intestinal fluids
How does hyperaldosteronism affect potassium?
potassium is constantly secreted into the nephron and lost in urine
what are the clinical manifestations of hypokalemia?
flat T wave
elevated U wave
Metabolic alkalosis
fatique, aneroxia, weakness, decreased bowels, arrhythmias
What are the major causes of hyperkalemia
decreased renal excretion of potassium
rapid admin of potassium
Acidosis
commonly seen in patients with untreated kidney injury / also patients with hypoaldosterone or Addison disease
What is phase 1 of postanesthesia?
Immediate recovery
Intensive nursing
Transitions to inpatient or PACU
What is phase 2 of postanesthesia
prepared to transfer to inpatient or extended care or discharge
What are the indicators of hypovolemic shock/hemorrhage
Pallor
Cool moist skin
rapid respirations
cyanosis
rapid, weak thready pulse
Decreased pulse pressure
low BP
concentrated urine
