Fluid Regulation and Electrolytes Flashcards
intake comes from 2 main sources
Ingestion (food and drink) – Obviously the main way
Metabolic byproduct of carbohydrate oxidation (small amount)
There are 4 main sources of daily loss of body water
- Insensible loss – Diffusion through skin and respiratory evaporations
Not precisely regulated - Sweat
- Feces
- Urine
For an average adult male (70 kg), total body water is ___% of total weight
60
There are two main body compartments for fluid
Intracellular Fluid
Extracellular Fluid
The Extracellular Fluid compartment can be further broken down into
Interstitial Fluid
Plasma
The composition of the extracellular and intracellular compartments must be ____ in order for various cellular functions to occur
significantly different
The Extracellular fluid has high concentrations in _____
Sodium, Chloride, and somewhat high in Bicarbonate
The composition of the Extracellular fluid is carefully regulated by the ____ to ensure proper concentration for cell function
kidneys
The Intracellular fluid has concentrations higher in ___
Potassium, Phosphate, Protein, and a little higher levels of Magnesium
A very important feature of the fluid compartments is the ability of ____ between the intracellular and extracellular compartments
fluid exchange
The forces that help to drive the fluid into or out of the cell is that of _____
osmolarity – maintaining an Osmotic Equilibrium
Isotonic
When the osmotic pressure is the same outside the cell as it is inside, no fluid shift is necessary
If there is a rapid increase in the water volume of the extracellular fluid, osmotic pressures drive some of that fluid into the cells, causing _____
cell swelling (hypotonic)
If there is a rapid loss of water content in the extracellular fluid, osmotic pressures drive fluid from inside the cell to outside, causing the cell to _____
shrink (hypertonic)
Managing the extracellular fluid volume is determined mainly by the balance between _____
sodium intake and output
ADH is secreted during times of ____, which results in reabsorption of water in the nephron tubules
water deficits
There are two main variables the kidney can use to manage sodium and water excretion
Glomerular Filtration
Tubular Reabsorption
Essentially all of the intravascular sodium is filtered into the ____ system
tubular
____ and ____ are two hormones that trigger increased sodium reabsorption when necessary
Angiotensin II; Aldosterone
A laboratory measurement that is readily available to the clinician for evaluating a patient’s fluid status is the ____
serum Sodium concentration
When plasma sodium concentration is less than 135 mEq/L, the patient is said to have ___
Hyponatremia
On the other hand, if sodium is greater than 145 mEq/L, the patient is said to have ____
Hypernatremia
Decreased serum sodium concentration can result from what two things
Loss of sodium from the extracellular fluid
Addition of excess water in the extracellular fluid
A primary ____ of sodium usually results in hyponatremia and dehydration and is associated with ____ extracellular volume
loss; decreased
What is Syndrome of Inappropriate Antidiuretic Hormone (SIADH) is common associated with?
Hyponatremia
Signs and symptoms of brain swelling due to hyponatremia
Nausea with or without vomiting
Malaise and/or headache
Decreased level of consciousness
Seizures
Coma
Increased serum sodium concentration in hypernatremia can result from
Loss of water from the extracellular fluid
Excess sodium in the extracellular fluid – more common
A primary loss of water usually results in ____
hypernatremia and dehydration and can be associated with Diabetes Insipidus
Commonly, hypernatremia occurs secondary to addition of ___ to extracellular fluid, which ultimately results in overhydration
excessive sodium
During hypernatremia, the extracellular fluid is ____
hyperosmolar
T/F Edema can be intracellular or extracellular
T
Swelling within the cells of the body can occur with 3 conditions
Hyponatremia
Depression of the metabolic processes of the tissues
Lack of adequate nutrition to the cells
What is Anoxic Brain Injury an example of?
Intracellular edema
There are two means of extracellular edema development
Failure of lymphatics to return fluid back to the blood
Abnormal leakage of fluid from the plasma across capillaries
Blockage of lymph return can result in _____ edema
non-pitting edema
Abnormal leakage of fluid from the plasma into interstitial spaces across the capillaries can result from several disease processes and is often seen clinically as ____ edema
pitting
Increased hydrostatic pressure, decreased oncotic pressure, and/or increased capillary permeability can lead to ____
edema
_____ are those spaces that can occur between two adjacent anatomic structures that are normally pressed together
Potential spaces
Examples of potential spaces
Pleural cavity
Synovial cavities
Pericardial cavity
Peritoneal cavity
When fluid accumulates in potential spaces, we call it ____
Effusion
Except peritoneal (Ascites)
There are two types of Effusions
Transudative
Exudative
_____ are composed mostly of fluid from the plasma, with little to no protein
Transudative Effusions
____ Effusions are composed of plasma with high levels of protein
Exudative
____ is the predominant intracellular ion
Potassium
Secretion of Potassium by special cells called ____ occurs in the late distal tubules and collecting ducts
Principal Cells
Active secretion of potassium requires a 2-step process
- Sodium-Potassium pump on the basolateral membrane pulls potassium into the cell, creating a gradient
- Passive diffusion of potassium out of the cell into the tubule
What hormone works on these Principal cells to increase Potassium secretion when needed, and also increases Sodium (and water) reabsorption
Aldosterone
99% of Calcium is stored in ____
our bones
Parathyroid hormone is an important regulator of serum _____
Calcium levels
__% of filtered Calcium is reabsorbed from the tubules and __% excreted
99; 1
About 85% of our total body ____is stored in the bones with calcium
phosphate
Most filtered ____ is reabsorbed, but if necessary, large amount can be excreted
magnesium
