Kidney disease and renal failure

Question 1

What are the homeostatic functions of the kidney?

Answer 1

elimination of waste
Water homeostasis
Electrolyte homeostasis
acid base homeostasis
Blood pressure control

Question 2

What are the metabolic/endocrine functions of the kidney?

Answer 2

Synthesis of hormones - Vitamin D, Erythropoietin, Renin

Excretion of drugs and drug metabolites.

Question 3

What diseases can cause the kidneys to stop working?

Answer 3

Chronic kidney disease (CKD)

Acute Kidney Injury (AKI)

Question 4

What are common causes of CKD?

Answer 4

Diabetes and or hypertension but also many other causes.

Usually slow and progressive onset and is often irreversible.

Question 5

What are the common causes of AKI?

Answer 5

Rapid onset usually due to a combination of systemic illness and multiple risk factors and medication.

Usually reversible with treatment.

Question 6

What is likely to develop AKI?

Answer 6

Elderly
Diabetics
Hypertension patients
Heart disease patients
Liver disease Patients
CKD patients

Question 7

Who is likely to develop CKD?

Answer 7

Diabetics
hypertension
Drug users especially NSAIDs
Elderly

Question 8

What are the risk factors for CKD?

Answer 8

Increased age
Hypertension
Diabetes
Smoking
Poor education

Question 9

What are some consequences due to a loss of renal function?

Answer 9

High mortality rate
Problems with electrolyte and water homeostasis
Acid base homeostasis issues
Endocrine irregular functionality.

Question 10

what is the average cardiac output?

Answer 10

5L/min

Question 11

What is the average renal blood flow?

Answer 11

1.2L/min

Question 12

What is the average glomerular filtration rate?

Answer 12

125L/min (180-185 L/day)

Question 13

What is the average urine volume?

Answer 13

1mL/min

1.5L/day

Question 14

What controls water and electrolyte homeostasis?

Answer 14

ADH and renin-angiotensin system

Question 15

What happens if salt and water homeostasis fails?

Answer 15

Inability to concentrate urine

Inability to excrete water load (oedema)

Sodium retention - hypertension, CNS dysfunction

Question 16

What happens if potassium homeostasis fails?

Answer 16

Enormous functional reserve to excrete potassium

Severe Hyperkalaemia (when GFR <10ml/min)

Alterations in membrane excitability

Cardiac arrythmias

Question 17

What causes to problems with acid base dysregulation?

Answer 17

Failure to excrete acid
Increase in H+
Increase in CO2 produced
Removed by lungs to maintain pH

Question 18

What happens if acid base homeostasis fails?

Answer 18

Systemic acidosis

Symptoms of breathlessness (dyspnoea)

Physiological systems start to fail (enzyme function requires correct pH)

Cardiac muscle concentration is reduced

Acidosis drives Hyperkalaemia

Question 19

What happens if vitamin D is not activated?

Answer 19

Hypocalcaemia
Muscle Spasms
Cardiac Rhythm problems
Hyperparathyroidism

Question 20

What is hyperparathyroidism?

Answer 20

Bone fragility

Soft tissue calcifcation

Question 21

What is caused if erythropoietin is not made?

Answer 21

Anaemia

Question 22

What are the consequences of anaemia?

Answer 22

Impaired quality of life

reduced exercise capacity

impaired cognition

Transfusion requirement

Iron overload

Blood-borne infection

↑ risk of Left Ventricular Hypertrophy

↑ CV disease in patients with CKD

Question 23

What happens if metabolic waste products are not excreted?

Answer 23

Accumulation of toxic waste products.

Can lead to confusion and heart problems

May cause Gout

May cause cardiovascular disease

Question 24

Why are the metabolic waste products that would lead to heart problems, gout and confusion when accumulated?

Answer 24

Creatine rises after significant renal damage

Retention of nitrogenous waste

Retention of urate

Retention of phosphate

Question 25

What is the role of the kidneys in drug metabolism?

Answer 25

Many drugs excreted by the kidney  Metabolism of drugs may be impaired by renal failure Increased risk of toxicity due to accumulation of drug

Question 26

What are some complications caused by the loss of kidney function?

Answer 26

Anaemia  Hypertension  Disturbed calcium/phosphate homeostasis  Cardiovascular disease  Bone disease  Abnormal handling of drugs  Immune suppression  Bleeding tendency Complications of treatment

Question 27

Why would you give a patient renal replacement therapy?

Answer 27

If they have acute or chronic kidney disease If they are unable to maintain homeostasis functions of the kidney. Without treatment these are terminal illnessses

Question 28

What are some renal replacement therapies?

Answer 28

Dialysis Conservative (palliative) care Transplantation replaces all kidney functions

Question 29

What is dialysis?

Answer 29

Extracorporeal therapy where fluid and solutes are removed or added to the patients blood.

Question 30

How does dialysis work?

Answer 30

Works by separating the patients blood and the dialysis fluid with a semipermeable membrane

Question 31

What is dialysis used to replace?

Answer 31

Used to replace the kidneys function of water, electrolyte, acid/base homeostasis and excrete metabolic waste products.

Question 32

What are the types of dialysis?

Answer 32

Haemodialysis Peritoneal

Question 33

Where is peritoneal dialysis done?

Answer 33

At home needs a permanent peritoneal catheter Can be either continuous or overnight dialysis

Question 34

How long does peritoneal dialysis last for?

Answer 34

8-10 years

Question 35

What are the risk factors of peritoneal dialysis?

Answer 35

Risk of getting peritonitis

Question 36

How does peritoneal dialysis work?

Answer 36

Dialysate is injected into the abdomen through a catheter. This draws out the metabolic waste, electrolytes and excess fluid from the blood This fluid is then drained out of the abdomen into a collection bag back through the catheter.

Question 37

How does Haemodialysis work?

Answer 37

Preparation of an AV fistula or AV graft to connect a vein and artery together. Need is placed into the vein and the blood flows out and into a dialysing machine which filters and cleans the blood. The clean blood is then returned to the body through a needle into the artery.

Question 38

What does haemodialysis require?

Answer 38

Needs permanent access to the circulation via an AV fistula, AV graft or central venous catheter.

Question 39

How long does haemodialysis last for?

Answer 39

Must be done for 4 hours 3 times per week and can last indefinitely

Question 40

What immunosuppressants are used for a kidney transplantation?

Answer 40

Steroids Calcineurin inhibitors Azathioprine Mycophenolate

Question 41

What are the benefits of a kidney transplant?

Answer 41

Better life expectancy Better quality of life (no dialysis) Replaces all renal functions First choice treatment for CKD 5 (end stage kidney failure)

Question 42

Who should have a kidney transplant?

Answer 42

Everyone with CKD 5 unless they have an absolute contraindication

Question 43

What are absolute contraindications?

Answer 43

High peri-operative mortality Poor life expectancy Active malignancy

Question 44

Where do the donor kidneys for a transplant come from?

Answer 44

Cadaveric donor Living donor

Question 45

Explain the problem of transplant immunology

Answer 45

Organ transferred between non-genetically identical individuals Rejection of the graft Driven by an allogenic response Mechanisms that discriminate self from non-self

Question 46

How can transplant immunological problems be prevented?

Answer 46

ABO blood group matching HLA-A,B,DR matching Screening for anti donor antibodies in the recipient.