fluids

Question 1

What is Osmosis

Answer 1

movement of water through a semipermeable membrane across a concentration gradient. Water moves from an area of low particle concentration (hypotonic) to areas of higher particle concentration (hypertonic) until the concentration is equal.

Question 2

What is osmolality

Answer 2

determined by the number of dissolved particles (sodium, urea, & glucose) per kilogram of water or solvent (sodium being the largest contributor)

Question 3

What is osmolarity

Answer 3

the number of osmoles of solute in a liter of solution

Question 4

Hypo-osmolar

Answer 4

lower solute concentration than plasma – low osmolality = low osmotic pressure

Question 5

Iso-osmolar

Answer 5

the same solute concentration as plasma – equal osmotic pressure

Question 6

Hyper-osmolar

Answer 6

higher solute concentration than plasma – higher osmolality = high osmotic pressure

Question 7

Aldosterone

Answer 7

secreted from the adrenal cortex in response to ↓ serum Na in the ECF or ↑ Na level in the urine. Aldosterone promotes sodium reabsorption and potassium excretion from the renal tubules, decreases water loss. Water follows sodium.

Question 8

ADH (Vasopressin or Antidiuretic hormone)

Answer 8

regulates water. Produced by the hypothalamus and stored in the posterior pituitary gland. It is secreted in response by osmoreceptors in the hypothalamus to an ECF volume deficit or ↑ osmolality. ADH promotes water reabsorption from the distal tubules of the kidneys.

Question 9

Dextrose is part of an IV solution and

Answer 9

metabolizes quickly

Question 10

Hypotonic IV fluids in bag

Answer 10

Osmolarity is < 270
½NS (or .45NS or 0.45% sodium chloride)
D5W – after dextrose has metabolized – free water source
¼ NS
¼ LR

Question 11

Isotonic IV fluids in bag

Answer 11

Osmolarity = 270-300
NS or 0.9% Sodium Chloride
Lactated Ringers
D5½NS
D5½LR

Question 12

Hypertonic IV fluids in bag

Answer 12

Osmolarity is > than 300
D5NS: replacement of fluid, Na, chloride and calories
D5LR: replacement solution
3% Normal Saline
D10 (Dextrose 10%)
D50 (Dextrose 50%)
Albumin

Question 13

Constant use of hypertonic solutions may cause

Answer 13

dehydration

Question 14

2 types of fluid imbalances can occur

Answer 14

fluid volume deficit (hypovolemia or dehydration) fluid volume overload (hypervolemia)

Question 15

If there is a fluid imbalance what should you assess(which one is the #1 indicator of a fluid imbalance)

Answer 15

daily weight
I/O’s
clinical manifestations of imbalance