renal failure

Question 1

role of the kidneys

Answer 1

• elimination of waste
• control of fluid balance
• regulate acid/base balance
• produce hormones
• regulate electrolytes

Question 2

types of acute kidney injury

Answer 2

• pre-renal
• renal
• post-renal

Question 3

managing AKI

Answer 3

approach

• identify high-risk patients
• assess & optimise volume status
• stop all nephrotoxic drugs
• review medications cleared by kidneys & adjust dose
• monitor creatinine & urine output
• non-invasive and invasive diagnostics
• daily weighing
• diet
• targeted therapy

Question 4

risk factors for AKI

Answer 4

• CKD
• age >75yrs
• diabetes
• CHF
• liver failure
• nephrotoxic medications (NSAIDs, gentamicin, ACEi)
• past history of AKI

Question 5

diagnostic for different types of AKI

Answer 5

pre-renal = assessment of volume status

renal = biopsy

post-renal = ultrasound (obstruction etc)

Question 6

define chronic kidney disease

Answer 6

a decline in function as defined by an increase in creatinine or the presence of albuminuria that’s been present for 3 months or more

Question 7

risk factors for CKD

Answer 7

• age
• sex
• obesity
• smoking
• ethnicity
• low income

Question 8

different ways of calculating GFR

Answer 8

1. clearance of artificially injected substances

2. creatinine clearance

Question 9

inulin clearance

Answer 9

• sugar, filtered by glomerulus & no tubular secretion or reabsorption
• gold standard - inject inulin into blood and measure clearance in urine

Question 10

creatine clearance

Answer 10

• produced by creatinine metabolism (reflects body size, m mass)
• freely filtered at glomerulus thus used to estimate eGFR
• as kidney function & GFR declines, creatine secretion from tubules increases

Question 11

determining prognosis in CKD

Answer 11

• GFR & albumin used to give risk for developing ESKD

- also marker of mortality, CVD, hospital admission

Question 12

causes of CKD

Answer 12

• diabetic nephropathy
• glomerulonephritis
• hypertensive nephrosclerosis
• polycystic kidney disease

Question 13

secondary factors (don’t cause it but contribute to progression)

Answer 13

• hypertension
• glomerular hypertrophy
• Ca, P abnormalities
• dyslipidaemia
• proteinuria

Question 14

hypertension treatment

Answer 14

• aim for <140/80
• lifestyle changes = weight loss, salt restriction, exercise, smoking, alcohol moderation
• most CKD patients need multiple drugs for hypertension
  - diuretics (inducing naturesis)
  - RAAS blockers (e.g. ACEi)
  - sympathetic blockers

Question 15

proteinuria treatment

Answer 15

• weight loss
• BP <150/70
• drugs:
  - ACEi or AIIA
  - spironolactone
  - statins
  - moderate protein restriction

Question 16

Ca & P abnormalities

Answer 16

• increased Ca2+ & P associated with progressive renal impairment
• phosphate restriction, phosphate barriers

Question 17

consequences of CKD

Answer 17

• more prone to both dehydration & fluid overload (avoid volume depletion)
• anemia from EPO insufficiency
• metabolic acidosis due to lack of acid excretion

Question 18

describe uremia and its symptoms

Answer 18

• symptomatic ESKD
• due to lack of toxin clearance
• fatigue, lethargy, sleep disturbances, headaches, seizures

Question 19

systemic effects of uremia

Answer 19

haematological = anemia, bleeding, prone to infection
CVS = hypertension, HF, cardiomyopathy, CVA, PVD
pulmonary = pleuritis
GI = anorexia, nausea, vomiting

Question 20

management of uremia

Answer 20

• treat primary disease, secondary factors
• avoid nephrotoxins
• correct abnormalities = Hb, Ca, P, acid/base, volume
• renal replacement therapy

Question 21

ESKD treatment

Answer 21

• dialysis (peritoneal, haemodialysis)
• renal transplant
• palliative