SM_199a: IVF and Diuretics Flashcards
Describe the normal values of electrolytes
Normal values of electrolytes
Na+: 140
K+: 4
Cl-: 102
HCO3-: 24
BUN: 10-20
Cr: 1.0
Glucose: 60-100
____ of total body water is intracellular, while is ____ of total body water is extracellular
2/3 of total body water is intracellular, while is 1/3 of total body water is extracellular
Of the extracellular water, ___ is intravascular (plasma), while ___ is extravascular
Of the extracellular water, 1/4 is intravascular (plasma), while 3/4 is extravascular
___ of extracellular water is plasma (intravascular)
1/4 of extracellular water is plasma (intravascular)
____ is the compartment we measure when we sample blood
Plasma is the compartment we measure when we sample blood
Kidney maintains the values in the ____ compartment in steady state
Kidney maintains the values in the plasma compartment in steady state
___ is the main cation in the extracellular compartment
Na+ is the main cation in the extracellular compartment
____ concentration controls the volume of the extracellular space
Na+ concentration controls the volume of the extracellular space
You would want to give IVF to _____, _____, or _____
You would want to give IVF to replete volume (give Na+ containing fluid), treat dehydration (give water), and maintenance if person not taking anything in by mouth
The calculation for serum osmolality is _______
The calculation for serum osmolality is 2*Na+ + BUN/2,8 + glucose/18
Normal serum osmolality is ______
Normal serum osmolality is 285-295
Types of IVF include _____ or _____
Types of IVF include glucose or Na+
5% dextrose (D5W) has osmolarity of ______
5% dextrose (D5W) has osmolarity of 278 (near serum)
(sugar is metabolized, leaving only the water to be distributed according to body water distribution)
After adding 1L of D5W, there is a _____ mL increase in ICF volume and a _____ mL increase in ECF volume
After adding 1L of D5W, there is a 667 mL increase in ICF volume and a 333 mL increase in ECF volume
(2/3 goes to ICF and 1/3 to ECF b/c near serum osmolality)
After adding 1L of D5W, there is a _____ mL increase in plasma volume
After adding 1L of D5W, there is an 83 mL increase in plasma volume
(1/3 goes to ECF and 1/4 of that goes to plasma so (1/3)*(1/4)*1000 = 83)
IVF is infused into the _____
IVF is infused into the plasma compartment
(IVF osmolarity should be similar to plasma to avoid injury to cells in plasma)
Normal saline is close to _____ with serum
Normal saline (0.9% saline) is close to isotonic with serum
(osmolality of 308 - 154 mEq of Na+ and 154 mEq of Cl-)
After adding 1L of normal (0.9%) saline, there is a _____ mL increase in ICF volume and a _____ mL increase in ECF volume
After adding 1L of normal (0.9%) saline, there is a 0 mL increase in ICF volume and a 1000 mL increase in ECF volume
(all of the saline goes to ECF b/c isotonic)
After adding 1L of normal (0.9%) saline, there is a _____ mL increase in plasma volume
After adding 1L of normal (0.9%) saline, there is a 250 mL increase in plasma volume
(all of the saline goes to the ECF, and the plasma volume is 1/4 of the ECF volume)
After adding 1L of half normal saline (0.45%), there is a _____ mL increase in ICF volume and a _____ mL increase in ECF volume
After adding 1L of half normal saline (0.45%), there is a 333 mL increase in ICF volume and a 667 mL increase in ECF volume
(think of as adding 500 mL pure water and 500 mL normal saline)
After adding 1L of half normal saline (0.45%), there is a _____ mL increase in plasma volume
After adding 1L of half normal saline (0.45%), there is a 167 mL increase in plasma volume
(167 + 500 = 667 mL go to ECF and 1/4 of that goes to the plasma)
After adding 1L of lactated ringers, there is a _____ mL increase in ICF volume and a _____ mL increase in ECF volume
After adding 1L of lactated ringers, there is a 100 mL increase in ICF volume and a 900 mL increase in ECF volume
After adding 1L of lactated ringers, there is a _____ mL increase in plasma volume
After adding 1L of lactated ringers, there is a 225 mL increase in plasma volume
(900 mL goes to ECF and 1/4 of that goes to plasma)
All IVF starts in the ______
All IVF starts in the vascular space
If IVF contains glucose only, it redistributes according to _____
If IVF contains glucose only, it redistributes according to total body water
(good for treating dehydration, which is loss of water)
Saline containing IVF will stay in the ______
Saline containing IVF will stay in the ECF
(better for treating hypovolemia, which is volume depletion causing issues with perfusion)
D5W is good for treating ______
D5W is good for treating dehydration (loss of water)
Saline containing IVF is good for treating _____
Saline containing IVF is good for treating hypovolemia (volume depletion causing issues with perfusion)
Insensible water loss is water loss that is ______
Insensible water loss is water loss that is not easily measured (skin, respiratory losses)
If a patient is not taking anything by mouth, give _____
If a patient is not taking anything by mouth, give D5W
If the patient is volume depleted, need ____
If the patient is volume depleted, need Na+
(to replete vascular space and assist perfusion)
_____ is a great choice for volume reuscitation of patients who are volume depleted
Normal saline is a great choice for volume reuscitation of patients who are volume depleted
(provides Na+ and Cl- the kidney needs to maintain volume)
(lactated ringers also works b/c provides K+ and Cl-)
Administer either _____ or _____ for volume depleted patient
Administer either normal saline or lactated ringers for volume depleted patient
If someone is volume depleted, you want to cover the _____ but also _____
If someone is volume depleted, you want to cover the volume already lost but also ongoing losses
Giving normal saline as a maintenance fluid results in a _____
Giving normal saline as a maintenance fluid results in a large salt load
(lot of Na+ in normal saline)
If euvolemic and hyperosmotic, give ____
If euvolemic and hyperosmotic, give IV D5W
If hypovolemic and hyperosmotic, ____
If hypovolemic and hyperosmotic, replace the volume deficit via a salt-containing solution
____ of Na+ is reabsorbed at the PCT, _____ at the TAL, and _____ at the DCT
60% of Na+ is reabsorbed at the PCT, 30% at the TAL, and 7% at the DCT
_____ fine tunes Na+ reabsorption
Cortical collecting duct fine tunes Na+ reabsorption
An example of a proximal tubule diuretic is ______
An example of a proximal tubule diuretic is acetazolamide
Acetazolamide (proximal tubule diuretic) ______, inhibiting ______
Acetazolamide (proximal tubule diuretic) inhibits carbonic anhydrase, inhibiting Na+ reabsorption, HCO3- reabsorption, and H+ secretion
(carbonic anhydrase promotes absorption of Na+ with HCO3-)
Acetazolamide causes less _____ and _____ reabsorption
Acetazolamide causes less Na+ and HCO3- reabsorption
(acidosis through decreased bicarbonate reabsorption)
Describe characteristics of acetazolamide
Characteristics of acetazolamide
- Works in proximal tubule
- Weak diuretic because the rest of the nephron can compensate for the Na+ being lost
- Causes a non-anion gap metabolic acidosis
- Used to treat metabolic alkalosis, particularly if volume overloaded
_____, _____, and _____ are loop diuretics
Furosemide (Lasix), torsemide (Demadex), and bumetanide (Bumex) are loop diuretics
Loop diuretics act in the _____
Loop diuretics act in the thick ascending loop of Henle
Loop diuretics inhibit the _____ in the _____
Loop diuretics inhibit the Na+/K+/2Cl- in the thick ascending limb of the loop of Henle
Describe characteristics of loop diuretics
Characteristics of loop diuretics
- inhibit the Na+/K+/2Cl- in the thick ascending limb of the loop of Henle
- Side effects: fluid and electrolyte imbalances (hypokalemia, hypocalcemia, hypomagnesemia), volume depletion, ototoxicity, hyperuricemia, hyperglycemia, increased LDL and TG
- Used for volume overload (rapid diuresis), HTN particularly in CKD
_____, _____, and _____ are thiazides
Hydrochlorothiazide, chlorthalidone, and metolazone are thiazides
Thiazides act in the _____
Thiazides act in the distal convoluted tubule
Thiazide diuretics inhibit the _____ in the _____
Thiazide diuretics inhibit the Na+/Cl- in the distal convoluted tubule
Describe characteristics of thiazides
Characteristics of thiazides
- Inhibit the Na+/Cl- in the distal convoluted tubule
- Side effects: impotence, fluid and electrolyte imbalances (hypokalemia, hyponatremia, hypercalcemia), impaired glucose tolerance, increased cholesterol
- First line treatment in HTN
_____ may cause hypokalemia and hypercalcemia
Thiazides may cause hypokalemia and hypercalcemia
_____, _____, _____, and _____ are K+ sparing diuretics
Triamterence, amiloride, spironolactone, and eplerenone are K+ sparing diuretics
K+ sparing diuretics act in the ______
K+ sparing diuretics act in the cortical collecting duct
(trap more Na+ in urinary space)
Trimaterene and amiloride inhibit ______
Trimaterene and amiloride (K+ sparing) inhibit renal epithelial Na+ channels in the late distal tubule and collecting duct
Spironolactone and eplerenone inhibit the ______
Spironolactone and eplerenone inhibit the mineralocorticoid receptor on epithelial cells in the late distal tubule and cortical collecting duct
Describe side effects of K+ sparing diuretics
Side effects of K+ sparing diuretics
- Amiloride and triamterence: hyperkalemia, nausea, vomiting
- Spironolactone: hyperkalemia, gynecomastia
(adjunctive treatment with other diuretics to avoid hypokalemia)
Describe the main points about diuretics
Diuretics
- Evoke natriuresis through inhibition of ion channels in different sections of the nephron
- Lower blood pressure by decreased intravascular volume, vasodilation with chronic use
- Main side effects are electrolyte abnormalities and volume depletion
