Renal Dysfunction Flashcards

1
Q

3 points of relevance for renal dysfunction…

A
  • All clients and patients are at risk of experiencing conditions resulting in a critically low BP therefore at risk of hypotensive induced actuate kidney injury
  • In adults, children and young people with chronic kidney disease and no obvious acute illness a rise in serum creatinine may indicate actuate kidney injury (NICE, 2019)
  • 20% of all admissions to hospital will have acquired AKI as part of that episode
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is acute kidney Injury (AKI)?

A
  • This is where your kidneys suddenly stop working properly.
  • It can range from minor loss of kidney function to complete failure
  • AKI normally happens as a complication of another illness (IE sepsi)
  • It is not the result of a physical blow to the kidneys
  • This type of kidney damage usually seen in older people who are unwell with other conditions in the kidneys are also affected.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the latest Acute injury definition?

A
  • Acute kidney Injury (AKI) for or lay known as renal failure should be easily recognised by the onset of oligurea (low urine output) and anuria (virtually no urine output) and or deteriorating biochemistry (NCEPOD, 2009)
  • AKI will result in uraemia (elevated levels of urea in the blood stream), Acidosis, hyperkalaemia (elevated potassium in the blood stream) and ultimately death (NCEPOD, 2009)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is Oligurea ?

A

Low urine output

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is anurea?

A
  • Virtually no urine output
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is Uraemia ?

A
  • elevated urea levels in the blood stream
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is hyerkalaemia?

A
  • Elevated potassium levels in the blood stream .
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Acute kidney injury can be diagnosed when one of the following criteria is met …..
What is this criteria?

A

1- Serum Creatine rise by greater then 26 umol/ L within 48 hours
2- Serum Creatine rise 1.5 x from the reference value which is know or presumed to have occurred within 1 week
3- Urine output is less then 0.5 mls per Kg an hour for the last 6 consecutive hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the functions of the kidneys?

A
  • Fluid balance
  • Acid base balance
  • Reabsorption or water, glucose, and amino acids
  • Potassium and other electrolyte balance
  • Excretion of creatine
  • Control of BP
  • Secretion of Erythropoietin
  • Prostaglandin and endothelium production
  • Produces the final enzyme to produce vit D
  • Glucose reabsorption and glucogenisis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

MEGA PRINCIPLE 6

Hoe is your renal system an indirect indicator of cardiovascular function?

A
  • If your heart is beating well if your BP is good if your cardiac output perfusion to your organs is good, you will deliver good volumes of blood to your kidneys and you will produce good quantities and good quality urine.
  • If your BP becomes compromised that can cause a reduction in your urine output.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How much potassium do your kidneys excrete?

A
  • Kidneys excrete 80% of the bodies potassium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the issues associated with high levels of potassium?

A
  • High potassium is always associated with potential cardiac arrest because it interferes with the function of the small arterial node
  • High potassium interferes with the sodium potassium pump for normal nervous function
  • High potassium can also cause seizures
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do kidneys maintain Ph balance?

A
  • Kidneys produce bicarbonate ions and that contributes to maintaining normal Ph balance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How can AKI make someone acidotic?

A
  • A person with AKI may become acidotic because they are not excreting hydrogen.
    This causes 2 thing to happen
  • The excess acid in the blood stream will start to use up the alkaline buffer ( the bicarbonate)
  • At the same time your kidneys wont be producing any alkaline buffer (bicarbonate)
    So in the blood stream sodium potassium pump increase due to renal failure along with calcium, chloride but not bicarbonate tends to fall because it is not being produced and is being used up very quickly.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the anatomy of the kidneys?

A
  • They are partially supported by the 11th and 12th rib
  • 2 bean shaped organs located in the retroportioneal area of the superior lumbar region
  • Weigh approx 150g
  • Easily damaged by trauma to lumbar region such as road traffic accidents or sporting injuries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does the glomerulus filter the blood?

A

There is high pressure in the glomerulus caused by the efferent arteriolar as it is smaller then the afferent arteriole therefore causing pressure to build up in the glomerulus.

  • This allows filtrate to leave the glomerulus and enter the bow mans capsule
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Why can people with renal failure not eat protein?

A
  • Protein is a vital nitrogen source
  • In order to use the amino acids from proteins as an energy source the liver has to remove the nitrogenous component the amine group
  • the process to remove the amine group is called deamination
    -The nitrogenous part of the amino acid (NH2) is converted to ammonia (NH3) among then converted into urea before being excreted by the kidneys.
    This is why people with renal failure cannot eat protein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is creatine?

A
  • This is a biological waste product formed by the degradation of creatine in the muscle cells
  • It is transported into the kidney through the blood and eliminated from the body in urine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the characteristics of normal urine?

A
  • Clear and amber coloured due to the presence of urobilinogen (a break down of haemoglobin
  • Specific Gravity (SG) = 1003-1030
  • Ph of around 6-6.5
  • A healthy adult passes 1000- 1500 mls/ day 0.5 mls/kg/hour minimum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the urine Specific Gravity Test?

A
  • It compares the density of urine to the density of water
  • Your urine is usually lighter and usually has a lower specific gravity when your well hydrated
  • Urine specific gravity will fall between 1003 and 1030 if your kidneys are functioning normally
  • If specific gravity results are above 1030 it can indicate mild dehydration
  • The higher the number the more dehydrated you are
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Causes of high specific gravity.

A
  • Increased Concentration of solutes
  • Dehydration
  • Sweating
  • Fast resp rate
  • Urinary tract infection
  • decreased renal blood flow
  • Excessive anti diuretic hormone ADH secretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

High urine specific gravity can also indicate that you have extra substances in your urine.
What substances are these?

A
  • Glucose
  • Protein
  • Bilirubin
  • Red blood cells
  • White blood cells
  • Nitrates
  • Bacteria
23
Q

What are the causes of low urine specific gravity?

A
  • Decreased concentration of solute
  • Renal failure
  • Pyelonephritis
  • Diabetes insipidus
  • Acute tubular necrosis
  • Interstitial nephrons
24
Q

What is urine osmolality?

A
  • Urine osmolality is used to measure the number of dissolved particles per unit of water in the urine.
  • As a measure of urine concentration it is more accurate the Then specific gravity.
  • Urine osmolality is useful in diagnosing disorders of urinary concentration such as diabetes insipidus and in assessing hydration status.
25
Q

Several conditions can cause HIGH urine osmolality.

Name 4 of them …. GO

A

1- Congestive heart failure
2- Dehydration
3- High glucose
4- Acute Kidney Injury

26
Q

Several conditions can cause LOW urine osmolality.

Name 3 of them… GO

A

1- Excessive fluid intake or over hydration
2- Kidney failure
3- Renal tubular necrosis

27
Q

Normal urine should not contain PROTEIN or ALBUMIN

If these are present in urine what is the medical terminology for this?

A

Protein = Proteinuria
Albumin = Albuminuria
These occur if you have a urine infection

28
Q

Normal urine should not contain glucose.

If this is present in urine what is the medical terminology for that?

A

Glucose = Glcosuria

This is associated with diabetes mellitus

29
Q

Normal urine should not contain red blood cells.

If this is present in urine what is the medical terminology for that?

A

Red blood cells = haematuria

Small amounts of blood colour urine great or a smokey colour large amounts will turn it red

30
Q

Normal urine should not contain white blood cells.

If this is present in urine what is the medical terminology for that?

A

White blood cells = Leukocyturia

Urinary tract infection

Infected urine will have an offensive smell due to the bacteria acting on the urea to increase the ammonia levels and cloudy in colour due to the exudate

31
Q

Normal urine should not be cloudy.

If it is what does that indicate?

A
  • May be due to an infection but may also be caused by elevated calcium levels
  • Can be caused by increased phosphates
32
Q

Normal urine should not contain ketones

If this is present in urine what is the medical terminology for that?

A

Ketones= Ketonuria

  • These are essential the waste product of lipid (fat) metabolism and are associated with diabetes mellitus
33
Q

Normal urine should not contain NITRITES.

What are nitrites.

A
  • Nitrites are the breakdown product of nitrates
  • Over 90% of UTI’s are caused by gram negative bacteria which produce Nitrate reductase which is an enzyme that breaks down nitrates.
  • A positive nitrate test result can indicate a UTI. However since not all bacteria are capable of converting nitrates into nitrites you can still have a UTI despite a negative nitrate test
34
Q

A blood test will help diagnose Acute Kidney Injury. What will show up in a blood test if someone has an Acute Kidney Injury?

A
  • Ph
  • Electrolyte
  • Urea
  • Creatine
35
Q

What is serum osmolality?

A
  • This is a measure of the number of dissolved particles per unit of water in serum.

Normal serum osmolality is 270-300 mOSm/kg

In a solution the fewer the particles of solute in proportion to the number of units of water (solvent), the less concentrated the solution

36
Q

What does low serum osmolality mean?

A
  • It means that that a higher then usual amount of water in relation to this amount of particles dissolved in it and accompanies over hydration or oedema.
37
Q

What does a high serum osmolality indicate?

A
  • If the body has a high osmolality serum. (Greater then 300mOSm/kg )
  • Then secretion of ADH is increased and more water is reabsorbed leading to highly concentrated ursine being entreated.
  • An example of this would be pre- renal failure
38
Q

Why are kidneys so sensitive to damage?

A
  • Energy required for tubular function comes from aerobic metabolism within the mitochondria of the tubular cells.
  • Tubular cells deep within the medulla operate at the limit of oxidative metabolism and are particularly sensitive to ischemia (restriction of blood supply)
39
Q

What does to much fluid lead to?

A
  • High BP
  • Fluid overload
  • Pulmonary oedema
40
Q

What does to little fluid lead to?

A
  • Low BP
  • weakness
  • Fainting
41
Q

What do the Proximal tubules do?

A
  • They reabsorb the bulk of the filtered solute required to maintain fluid + electrolyte balance.
  • The elimination of potassium, water and hydrogen ions is regulated by the distal tubule
  • As renal perfusion and glomerular filtration diminish reabsorption of water and sodium by the proximal tubules rises from 60%- 90% so that minimal fluids reach the distal tubule
42
Q

What are the 3 classifications of renal failure?

A
  • Pre- renal, renal failure (before)
  • Intra- renal, renal failure direct damage
  • Post renal, renal failure ( after)
43
Q

What are the causes of pre- renal, renal failure?

A

Things that happen before the kidney to reduce renal blood flow.

  • Hypovoalemic shock
  • Hypotension
  • Dehydration
  • Bleeding
  • Renal artery thrombosis (clot)
44
Q

What are the causes of Intra- renal, renal failure?

A

Affects the kidney tissue directly (E.G sepsis)

  • Nephrotoxic substances; - Drugs ( i.e Gentomycin)
  • X- ray contrast
  • Industrial solvents
  • Tumours of the kidney
45
Q

What causes Post renal, renal failure?

A
  • Blockage of the ureters or bladder
  • Kidney stones, tumour of the bladder
  • Enlarged prostate
  • Back pressure that damages kidney - hydronephrosis ( build up of urine in the kidneys causing swelling) is an example of this
46
Q

3 facts about the renal blood supply?

A

1- 20-25% w=of the total cardiac volume is directed to the kidney via the abdominal aorta and left and right renal arteries
2- Renal blood flow = 1200ml/min
3- More then 99% of the glomerular filtrate returns to the blood stream via tubular reabsorption

47
Q

What is glomerular filtration?

A
  • This is the process where by the plasma is filtered across the capillaries of the glomerulus into the Bowman’s capsule
  • On average this equates to 180 litres in a 24 hour period for men and 150 litres per 24 hours for women
  • The amount of glomerular filtrate formed is known as Glomerular filtration rate (GFR) which is approx 125mls/min
48
Q

What are the pharmacological treatment options for Acute Kidney Injury?

A
  • Insulin and glucose can be used to promote temporal transfer of extra cellular fluid into cells
  • Sodium bicarbonate can be administered to buffer acidosis
  • Calcium can be given ti correct the raised serum potassium
    Renal replacement therapy (Dialysis)
49
Q

What is hypovolaemic shock?

A
  • Refers to a medical or surgical condition in which rapid fluid loss results in multiple organ failure due to inadequate perfusion.
  • It can be defined as shock caused by a severe decline in circulating blood volume mostly caused by trauma or haemorrhage
50
Q

There are 2 forms of Hypovolaemic shock what are they?

A

1- Absolute- is due to lower circulatory blood volume for a given vascular capacitance (e.g haemorrhage)

2- Relative - Resulting from an expanded vascular capacitance for a given blood volume (e.g sepsis)

51
Q

Why is hypovalaemia so important?

A
  • Almost all medical and surgical emergencies, consider hypovalaemia to be the primary cause of shock until proved otherwise. (RCUK, 2015)
  • This is why urine output is frequently considered as a reflection of cardiac output.
52
Q

What does Aldosterone do?

A
  • The renal system responds to haemorrhagic shock by stimulating an increase in renin secretion from the juxtaglomerular apparatus.
  • Renin converts angiotensin to angiotensin 1 which is subsequently converted into angiotensin 2 by the lungs 🫁 and the liver
  • Angiotensin 2 has 2 main effects; vasoconstriction of arteriolar smooth muscles and stimulation of aldosterone secretion by the adrenal cortex
  • Aldosterone increases salt and water consentration
53
Q

What is anti-diuretic hormone(ADH)?

A
  • ADH is released form the posterior pituitary glad in response to a decrease in BP (detected by baroreceptors) and a decrease in sodium concentration.
  • ADH indirectly leads to an increased reabsorption of water and salt by the distal tubule, the collecting duct and the loop of henle.

-

54
Q

If your BP, tissue perfusion, and perfusion to the kidney is low what will happen to the blood plasma Ph ?

A
  • The Ph will go down and your resps will go up