Exam 2: Thiazide Diuretics Flashcards
Thiazide diuretics work in the early part of the DCT (distal Convoluted Tubule), which is found in the “blank”
“Nephron”
Thiazide inhibits the cotransporters of what two electrolytes?
Na+ and Cl-
Thiazide diuretics stop Na+ and Cl- from reentering the body, instead staying in “blank” to be urinated.
staying in “filtrate” to be urinated.
Which is more powerful: Loop diuretics or Thiazide diuretics?
Loop diuretics are more powerful
Different Diuretics work on different structures of the nephron. Thiazide diuretics work at the DCT and account for what percentage of Na+ and Cl- reabsorption?
How does this compare to Loop diuretics?
5-7% of Na+ and Cl- reabsorption
Compared to loop diuretics 25%
In addition to blocking Na+ and Cl- reabsorption, Thiazide diuretics also increase the absorption of “blank”
Because of this, what is a risk for pt using Thiazide diuretics?
Ca+
Hypercalcemia
Thiazide diuretics are less effective in patients with a GFR (glomerular filtration rate) of less than “blank”
<30 mL/hr
If a patient has a compromised GFR, would a diuretic be given to them at all?
Yes, a loop diuretic would work
The DCT plays a role in reabsorbing what 3 electrolytes? What electrolyte does the DCT excrete?
Reabsorb:
Na+
Cl-
Ca+
Excrete: K+
Thiazides stop the Na+/Cl- cotransporters by stopping what from getting into the blood?
Na+ and Cl-
By stopping Na+ and Cl- from being reabsorbed, while enhancing the absorption of Ca+, Thiazide diuretics can lead to electrolyte imbalances like what?
Hyponatremia
Hypercalcemia
Since the DCT is responsible for excreting K+, and Thiazide diuretics are responsible for increasing excretions, what imbalance might this cause?
Hypokalemia
When taking a Thiazide diuretic, what diet change would you implement in a patient?
Increased Potassium diet
In DM patients, Thiazide D’s can alter their blood sugar levels, causing hyperglycemia and an increase in uric acid.
What does this uric acid increase lead to?
Gout attacks
What is a dangerous Uric Acid level in a patient?
> 7
What are the two primary uses for Thiazide Diuretics?
HTN and getting Na+ and H2O out of the blood through pissing to lower BP
Are Thiazide diuretics good for heart failure patients?
Yes, by lowering fluid volume to prevent fluid volume overload.
What 1st line HTN drug class can be mixed with Thiazide diuretics to increase heart function?
ACE inhibitors
What is a renal issue associated with Ca+ levels that can be treated with Thiazide diuretics?
Renal Calculi
These are Ca+ deposits that can be reabsorbed thanks to Thiazide diuretics.
Since Thiazide is a diuretic, what is a sign that the nurse should always look for in a patient?
Dehydration
Should you give a patient Thiazide diuretics’ at nighttime?
NO
What electrolytes would you expect to see elevated in a Thiazide diuretic patient?
What about low levels?
Elevated:
Hypercalcemia
Hyperuricemia
hyperglycemia
Low:
Hypokalemia
Hyponatremia
What drug combination (“blank” + Thiazide D) would be avoided in a patient with Hyponatremia?
What about Hypokalemia?
Hyponatremia is Lithium + Thiazide D
-Can cause Lithium Toxicity
Hypokalemia is Digoxin + Thiazide D
-Can cause Digoxin toxicity
The physician prescribes the patient a thiazide diuretic. The patient is experiencing increased urination. As the nurse you know that this medication causes this type of affect by how it affects the nephron. It does this by?
A. inhibiting the sodium-potassium-chloride cotransporter in the distal convoluted tubule
B. inhibiting the sodium-chloride cotransporter in the distal convoluted tubule
C. inhibiting the water reabsorption in the distal convoluted tubule
D. inhibiting the sodium-potassium transporter in the distal convoluted tubule
The answer is B. Thiazide diuretics inhibit the sodium-chloride cotransporter in the early part of the distal convoluted tubule. When this occurs it prevents sodium from being reabsorbed back into the blood. Since the sodium stays in the tubule, it will keep water with it. This will decrease the amount of water reabsorbed into the blood/body…thus increasing urination and extra fluid removal from the blood (causing a diuretic effect).