Chronic Kidney Disease

Question 1

Describe the distribution of body fluid

Answer 1

2/3s: Intracellular fluid
Volume = 28L
1/3: Extracellular fluid
11L Interstitial fluid (80% of ECF)
3L Plasma volume (20%)

Question 2

Determinants of fluid movement

Answer 2

Hydrostatic pressure (into IF)
Osmotic pressure (salt and electrolytes)
Oncotic pressure (protein)

Question 3

Hormones involved in fluid balance

Answer 3

Angiotensin II
Aldosterone (from adrenal cortex by angiotensin II)
ADH

Question 4

Functions of ADH in fluid balance

Answer 4

Vasoconstriction of blood vessels

Increased reabsorption of water in kidney

Question 5

Functions of Aldosterone in fluid balance

Answer 5

Increases water reabsorption and decreases urine volume

Increased BP

Question 6

Function of Angiotensin II on blood vessels

Answer 6

Vasoconstriction (increased BP)

Question 7

What is daily fluid intake for adults on a relatively sedentary lifestyle

Answer 7

1.5-2.5L

Question 8

Examples of fluid losses from body

Answer 8

Urination
Sweating
D+V
Surgery

Question 9

5 functions of kidney

Answer 9

Blood Volume/Fluid status
Waste/Toxin/Drug excretion
Vitamin D metabolism (Vitamin D to 1-hydroxyvitamin D)
Generates erythropoietin (red cell production)
Acid-Base Regulation (excretes H+ ions and reabsorbed HCO3- ions)

Question 10

Measurement of kidney function

Answer 10

Creatinine:
Waste product of muscle metabolism (but not good measurement in people with abnormal muscle mass)
Purely excreted by kidneys
Longstanding measure of kidney function

Question 11

DEscribe relationship between sCreatinine (y) and GFR (x)

Answer 11

Reciprocal or as GFR increases, sCr decreases (rapidly at start then decreases less rapidly)

Question 12

What is taken into account when calculating persons eGFR

Answer 12

Age
Gender
Race
(estimate how well the kidney is working)

Question 13

How to detect protein in the urine

Answer 13

Dipstick

Question 14

Give example of something that is excreted by the kidney on a constant rate

Answer 14

Creatinine

Question 15

How can you measure proteinuria/albuminuria

Answer 15

Albumin Creatinine Ratio
Albumin in urine can be diluted or concentrated depending on urine volume
Creatinine is excreted in the urine at a constant rate (irrespective of urine volume)
Therefore the ratio of albumin to creatinine should be constant irrespective of urine volume

Question 16

Describe staging of CKD

Answer 16

Good - GFR At least 60 and albuminuria <3mg/mmol;
Less good - GFR 45-59 and albuminuria <3mg/mmol; GFR at least 60 and moderatlly increased albuminuria 3-30mg/mmol
Quite bad - GFR 30-44 and albuminuria <3mg/mmol; GFR 45-59 and albuminuria 3-30mg/mmol; GFR at least 60 and albuminuria >30mg/mmol
Bad - all others (v low GFR and v high albuminuria)

Question 17

Aetiology of CKD

Answer 17

Any renal disease
Diabetes Mellitus
Glomerulonephritis
Cystic disease
AKI
Hypertension
Malignancy
Anatomical abnormality of renal tract
Hereditary disease e.g. polycystic kidney disease

Question 18

Management of hypertension in adults (pharmacological)

Answer 18

ACE inhibitor or Angiotensin Receptor Blocker (<55 years)
Calcium channel blocker (>55 or black)
->Both if no effect
->+Diuretic
Add another diuretic or alpha blocker or beta blocker

Question 19

Management of Cardiovascular risk - hypertension

Answer 19

Hypertension:
Treat systolic BP 140 or 130 if ACR >30g/g
RASi if ACR >30mg/g (diabetes) or 300mg/g (non-diabetes)
Consider <120 mmHg based on SPRINT

Question 20

Management of Cardiovascular risk - Dyslipidemia

Answer 20

Lipid lowering with statins

Treat as per high risk population guidelines

Question 21

Management of Cardiovascular risk - CKD specific

Answer 21

Phosphate
Vascular calcification
LVH
Inflammation
Vit D deficiency
Sodium/water excess
Electrolyte imbalance

Question 22

Management of Cardiovascular risk - other than CKD, dylipidemia or hypertension

Answer 22

Address lifestyle

Question 23

What causes anaemia in CKD

Answer 23

Iron deficiency
Liver produces Hepcidin
When kidney function is poor, the hepcidin builds up and inhibits iron absorption from the duodenum
Therefore iron levels are low

Question 24

One of the first important things to do in CKD is get iron levels up, how would you do this

Answer 24

Not oral as cant absorb iron through the duodenum

IV iron + Erythropoietin

Question 25

Examples of Renal Replacement Therapy

Answer 25

Haemodialysis
Peritoneal dialysis
Kidney transplant

Question 26

Peritoneal dialysis - what is it

Answer 26

Involves infusing a sugary solution into the abdomen which draws off toxins

Question 27

Transplanted kidneys

Answer 27

New kidneys not in same place as old kidneys (put lower down)
Put in iliac fossa

Question 28

How do you assess volume/fluid status

Answer 28

Urine volume (not great for dialysis patients)
JVP
Stethoscope to listen to bottom of lungs (fluid in lungs, may be crackly)

Question 29

Why do you see oedema more in the ankles

Answer 29

Oedema generally seen in ankles where hydrostatic pressure would be greater thus fluid is more likely to leak out despite similar oncotic pressure in the vessel
Hydrostatic pressure also increases when you’re fluid overloaded

Question 30

Give examples of drugs that could be contraindicated in case of dehydration

Answer 30

ACE inhibitors
ARBs
Diuretics
Metformin
NSAIDs (vasoconstriction of small arteries entering kidney)

Question 31

What can you give to treat dehydration

Answer 31

IV fluid

Question 32

When would you give less fluid for dehydration

Answer 32

Renal impairment

Cardiac failure