Diuretics

How the kidney’s produce urine has a DIFFERENT MECHANISM of how diuretics increase urine formation. TF?

How the kidney’s produce urine has a DIFFERENT MECHANISM of how diuretics increase urine formation. TF?

False

They have the SAME MECHANISM

Summary of the mechanism of Kidney Formation and how Diuretics work

Cells of the kidneys are made up of these filtering units called what?

Nephrons 

What are the different components of nephrons?

1. Glomeruli 

2. Renal Tubules 

Renal tubules are then divided into:

1. Proximal convoluted tubule

2. Loop of Henle

3. Distal Convoluted Tubule

4. Collecting Duct

What are the 2 Main Purpose of Diuretics?

1. Decrease Hypertension

2. Decrease Edema 

When you drink diuretics, increased urine production will increase blood volume. TF?

False

It will decrease blood volume, therefore decreasing hypertension.

Increased urine production will decrease blood volume. Because when you filter blood, urine ang product nun 

Diuretics also decrease hypertension by promoting what?

Vasodilation

Kaya kapag mas maraming ihi, mas konti ang natitirang blood volume. Kaya there is vasodilation. Vasoconstriction is an etiology of hypertension.

Diuretics can be ONLY used for CHF. TF?

False

It can be used on ANY kind of congestion including congestion of the heart.

Diuretics = Decreased Edema 

What are the different components of blood?

1. RBC

2. WBC

3. Platelet

4. Plasma 

What is the only component of blood that the glomeruli will filter that would proceed to the renal tubules?

Filtrate

Which is the Plasma minus the Protein 

Apart from this blood component, drug waste products and other waste products are also filtered by the glomeruli

What will the glomeruli not filter and bring back to the general circulation?

1. RBC

2. WBC

3. Platelet

4. Plasma Protein

Why can't the glomeruli not filter RBC, WBC, Platelet, and Plasma proteins? 

Because they are too large 

RBC, WBC, & platelet will not be filtered. They are too big.

Only plasma will be filtered. But in the plasma, there are also large particles that cannot be filtered–plasma protein.

Therefore, RBC, WBC, platelet, and plasma protein will go out to the efferent arteriole.

RBC, WBC, Platelet, and Plasma proteins that will not be filtered by the glomeruli will go back to the general circulation via the?

Efferent arteriole 

An efferent arteriole is a blood vessel in the urinary system that brings filtered blood from the glomerulus to the rest of the kidney and back to the general circulation.

This is a blood vessel in the urinary system that brings filtered blood from the glomerulus to the rest of the kidney and back to the general circulation.

Efferent arteriole 

What are the 5 Categories of Diuretics?

1. Thiazides

2. Loop or Furosemide

3. Osmotic or Mannitol

4. Carbonic Anhydrase Inhibitors or Acetazolamide 

5. Potassium Sparing (like Amiloride) 

What diuretic is used primarily for clients with normal renal function?

Thiazide

Ex. chlorothiazide

(Diuril) ○ bendroflumethiazide

(Naturetin) ○ methylclothiazide

Furosemide can cause what physiologic changes?

1. Ototoxicity

2. Photosensitivity

3. Hypotension

4. Skin Disturbances 

When taking mannitol, diuresis will occur within how many hour/s after IV administration?

1 to 3 hours 

This drug is weaker than thiazides and loop diuretics, so are used as mild diuretics or in combination with another diuretic.

Potassium Sparing 

What is the diuretic that is best given or combined with digitalis?

Potassium Sparing

This is because it promotes excretion of Na and Water but Retains Potassium, kaya used best in combination with digitalis, since no toxicity since hindi bababa yung K dahil nareretain sya sa body. 

Potassium Sparing is a strong diuretic. TF?

False

Amiloride is best combined with digitalis. TF?

True

Amiloride is an example of a Potassium Sparing Diuretic 

Which produces increased urine flow by inhibiting sodium and water reabsorption from kidney tubules?

Diuretics

Diuretics initiate urine formation, increase urine flow, and promote diuresis

Kidney is what produces urine 

Diuretics are the primary drugs for ___ because increasing urine flow will prevent congestion or edema of the heart.

Diuretics are the primary drugs for CHF

Whenever we filter blood, the blood goes into the ___ which delivers blood into the glomeruli.

The glomeruli only filters the particles or blood that pass through the drain. 

the blood goes into the afferent arteriole

What is the first step of urine formation?

Glomeruli Filtration

When the plasma minus the protein called filtrate which is the only blood component that is going straight to the proximal convoluted tubule

The plasma minus the protein called filtrate is the only blood component going straight to?

proximal convoluted tubule

What is the second step of urine formation?

Reabsorption

Here the nutrients, gasses, and hormones contained in the filtrate in the proximal convoluted tubule are reabsorbed back into the circulation via the peritubular capillary which is connected to the proximal convoluted tubule.

The second step of urine formation is Reabsorption

Here the nutrients, gasses, and hormones contained in the filtrate in the proximal convoluted tubule are reabsorbed back into the circulation via the peritubular capillary which is connected to the proximal convoluted tubule.

Take note that they are small particles, and these small particles are needed by the body. This is why they need to be reabsorbed back and not excreted. 

Kaya merong reabosoprtion since hindi lahat need itapon. Ngayon, yung mga di na-reabsorb is yun yung urine.

Now, as you go through along the proximal convoluted tubule, the filtrate is plasma minus protein. Hindi pa urine yun, but the filtrate contains a lot of nutrients, gasses, and hormones—at hindi mo yun pede mailabas sa urine. That’s why the second step of urine formation is reabsorption.

Ang karugtong ng efferent arteriole ay isang peritubular capillary. Everything that needs to be reabsorbed in the proximal convoluted tubule, returns to the peritubular capillary and is reabsorbed because you need to bring that to the systemic circulation

What is the third step of urine formation?

Tubular Secretion

wherein all waste products not reabsorbed in the filtrate are excreted out of the body via the collecting duct.

The third step of urine formation is Tubular Secretion

wherein all waste products not reabsorbed in the filtrate are excreted out of the body via the collecting duct.

Lastly, lahat ng kailangan itapon — remember may mga hindi nafilter initally

(Ex: drug waste products) — kailangan yun matapon pabalik sa renal tubules.

This is the third step of urine formation, tubular secretion.

• Nafilter, nireabsorb, sinecrete hanggang pagdating sa dulo urine nalang siya. It’s ready to come out.

• Ang mga diuretics, along the way, nandodoon yung mechanism of action nila. Usually by preventing reabsorption. Kaya dumadami yung water as it is being excreted in the urine.

• Kasi yung kidney nag-rereabsorb din sya nung water and sodium, so by taking a diuretic, hindi nirereabsorb ng kidney yung water and sodium, so dumadami yung urine at bumababa yung blood volume (since water and sodium contribute to blood volume in the body)

These are diuretics effective for edema which acts on distal convoluted tubule, beyond the loop of Henle, to promote Na, Cl, and H2O excretion.

Thiazides

This are diuretics that can also be used as an antihypertensive which actions directly on arterioles to cause vasodilation, but only for mild hypertension 

Thiazides .

This is a diuretic that can cause loss of K which is why you should not give it with digitalis since it can cause toxicity.

Apart from that, you should also cautiously give it to patients with diabetes since it can increase glucose in the blood.

Thiazides ..

These are high-ceiling diuretics that act on thick ascending loop of Henle to inhibit chloride transport of sodium into circulation.

Loop or Furosemide

This should not be used in conjunction with digitalis because it promote K loss.

However, in cases of severe congestion of the heart, it can be administered initially for it can make diuresis fast which would lead to rapid decrease of congestion of the heart.

Furosemide

Again it is not used in conjunction with digitalis, why?

Because of potassium loss, increasing digitalis toxicity, pero, because furosemide is a high ceiling loop diuretic, mabilis sya magpaihi.

Sometimes you will see in the clinicals that even with digitalis, binibigyan pa din ng furo initially, kasi ang goal is to make the diuresis fast (mabilis mawala ang congestion) so, pwedeng bigyan initially ng furosemide pero kailangan imonitor maigi na hindi aabot sa digitalis toxicity.

So again,just because of the reason that furosemide is a very potent diuretic lalo na pag may sever congestion ang heart.

This is given as IV push, but do not give it too quickly, you have to give furosemide it as a slow IV push.

The ideal is 1 cc per minute.

Because if you give it too quickly, it will increase the risk of ototoxicity.

Furosemide .

This is used to prevent renal failure, decrease ICP, and decrease IOP.

But most of the time, it is used for cerebral edema to decrease intraocular pressure. 

Osmotic or Mannitol

This is a diuretic given using an IV filter because you need to warm it so that no crystals will enter the circulation once given IV.

But to futher ensure that no crystals will enter it is given as an IV filter.

Mannitol

Furthermore, Mannitol increase osmolality and inhibits Na reabsorption in the proximal tubule and loop of Henle.

Again, ano yung naeexcrete from the human body because of this?

○ Na, Cl, K, and H2O all are excreted from the human body

This is a diuretic that block the action of carbonic anhydrase needed to maintain acid and base balance, which then causes increased Na, K, and HCO3 (bicarbonate) excretion.

Acetazolamide

This is a diuretic mostly used to decrease intraocular pressure in clients with open-angle (chronic) glaucoma. 

Acetazolamide .

T/F: Potassium Sparing is the only diuretic that does not excrete potassium. 

TRUE

This is a diuretic that blocks aldosterone receptors (which is an important hormone that regulates fluid electrolyte balance) and acts primarily on distal convoluted tubule and collecting duct to promote Na and H2O excretion and K retention.

Potassium Sparing