Chronic renal failure

Question 1

Management overview

Answer 1

1. Diet: Protein restriction with adequate calories K+ restriction Na and water restriction Phosphate restriction Avoid extra-dietary magnesium (antacids)
2. Medical: Treat secondary hyperPTH Calcium supplements Calcitriol Phosphate binder Vitamin D analogues Cinacalcet for hyperparathyroidism (sensitizes parathyroid to Ca2+, decreasing PTH) Sodium bicarbonate EPO ejections ACEi Statins Adjust medications Stop nephrotoxic medications. Statin therapy. Optimise diabetes management.
3. Dialysis
4. Renal translpant

Question 2

Prevention of progression

Answer 2

1. As management 2. Control HTN, DM, smoking cessation, physical activity, weight loss 3. Avoid neprhotoxins 4. Address reversible causes of AKI

Question 3

Presentation of renal failure

Answer 3

1. Volume overload 2. Electrolyte abnormalities 3. Uremic syndrome

Question 4

Complications of renal failure

Answer 4

Complications

• CNS: decreased LOC, stupor, seizure
• CVS: cardiomyopathy, CHF, arrhythmia, pericarditis, atherosclerosis
• GI: peptic ulcer disease, gastroduodenitis, AVM
• hematologic: anemia, bleeding tendency (platelet dysfunction), infections
• endocrine: ƒƒdecreased testosterone, estrogen, progesterone ƒƒ increased FSH, LH
• metabolic: ƒƒ renal osteodystrophy: secondary increased PTH due to decreased Ca2+, high PO4 3- and low active vitamin D ŠŠosteitis fibrosa cystica, ƒƒhypertriglyceridemia, accelerated atherogenesis, ƒƒdecreased insulin requirements, increased insulin resistance
• dermatologic: pruritus, ecchymosis, hematoma, calciphylaxis (vascular Ca2+ deposition)

Question 5

Indications for dialysis

Answer 5

HAVE PEE or AE IOU

Hyperkalemia (refractory)

Acidosis (refractory)

Volume overload (refractory)

Elevated urea (>35-50 mM)

Pericarditis

Encephalopathy

Edema (pulmonary)

Question 6

Number of people on RRT, number at risk of CKD, number of people with CKD

Answer 6

1. 1 in 1500 on RRT
2. 1 in 9 CKD
3. 1 in 3 at risk of CKD

Question 7

Risk factors

Answer 7

1. >60
2. ATSI
3. Diabetes
4. CVD
5. hypertension
6. smoking,
7. diabetes FHx,
8. obesity–>screen in adults >35 with
   risk

Question 8

Screening for CKD in ATSI

Answer 8

1. Screen for risk factors annually in 18-29 yo
2. All >30, 18-29 w/ risk factor: urine ACR, eGFR, BP every 1-2 years

Question 9

Systemic manifestations

Answer 9

1. Fluids and electrolytes: +K, deH, edema, metabolic acidosis, +Urea/Creatinine
2. Calcium, Phosphate and bone: renal osteodystrophy, secondary hyperPTH, hypocalcemia (-ve conversion vit D, -ve absorption in GIT, acidosis), hyperphosphatemia
3. Sexual dysfunction
4. Hematological: anemia (-ve EPO, blood loss due to defective PLTs), hemolytic
5. Cardiopulmonary: Pulmonary edema, cardiomyopathy, pericarditis, HTN
6. GIT: NVD, esophagitis, gastritic, colitis
7. Neuromuscular: myopathy, peripheral neuropathy, encephalopathy
8. Dermatologic: Sallow colour, dermatitis, pruritis, nodules

Question 10

Renal replacement therapy in acute setting indications

Answer 10

1. Metabolic acidosis
2. +K >6 despite other management
3. +plasma urea and creatinine
   > 30 mmol/L (180 mg/dL) and creatinine
   > 600 μmol/L (6.8 mg/dL)
4. Fluid overload w/ complications->pulmonary edema, heart failure
5. Uremic pericarditis/encephalopathy

Hemofiltration or hemodialysis

Question 11

Renal replacement therapy chronic: reasons for one over the other

Answer 11

1. Hemodialysis: more hemodynamically stable, more time consuming, must be in hospital, time away. Needs increased compliance with diet and fluids.

Risks: hemodynamic instability, bleeding, sepsis, hypersensitivity, air embolus, arrythmias

2. Peritoneal: more comfort, in own home, diet less restrictive. May not have suitable living, not stable household, non compliance, infection risk

Question 12

Complications and associated management: HTN, bone, albuminuria, glycemic control, anemia

Answer 12

1. HTN: a) Lifestyle b) ACEi first line, aim <130/80 in diabetic, 140/90 in others. Monitor eGFR/K. Cease if eGFR drop >25% in 2 months and reconsider/refer. If K 6-6.5 lower, K wasting diuretic, K diet restricting. If then X<6->stop and consider BB, CCB, thiazide. >6.5= emergency
2. Bone: Keep Phosphate and Ca in normal range, PTH 2-9 X upper limit, vitamin D.

Phosphate diet restriction (get dietician help)-> cheese, milk, eggs, use phosphate binders (Calcium carbonate)

Consider calcitriol in later stages.

If phosphate controlled, calcium leves usually improve.

3. Albuminuria: ACEi, ARB, reduce salt, use spirinolactone cautiously
4. Glycemic: Pre-prandial BSL 4.0-6.0 mmol/L
   HbA1c <7.0%/53mmol/mol

Hypoglycemics, diet, insulin, incretins, gliptins

5. Anemia:
   Hb 100 – 115 g/L
   Prior to commencement of epoetin: Ferritin > 100 μg/L
   TSAT >20%
   Once epoetin commenced: Ferritin 200-500 μg/L
   TSAT 30-40%

Need neprhologist.

Iron supplement

Rule out other causes->Vit B12, folate, TSH

Question 13

Mangement of complications: uremia, restless leg, hyperkalemia, sleep apnea, depression, acidosis

Answer 13

1. Uremia

Dialysis when urea ++

Low protein diet, fluid control

Antiemetics have limited value

2. Restless leg

Iron supplementation, baths and massages, compresses, levodopa, benzodiazepines

3. Hyperkalemia

Low K diet, correct acidosis, K wasting diuretics, resonium A powder, cease ACEi/ARB/Spirinolacton if >6.

4. Acidosis

?Sodium bicarbonate

5. Sleep apnea

Weight loss

Avoid CNS depressants

CPAP

6. Depression

Psychosocial intervention

Antidepressants at low dose

Question 14

Medications in CKD: drugs needing reduction, affects on kidney

Answer 14

1. Dose reduction

Anticoagulants–>dabigatran
Antivirals
Benzodiazepines, gabapentin, lithium
Colchicine
Digoxin
Exenatide, insuin, metformin
Sotolol, spirinolactone

Sulfonylureas
Opioid analgesics
Digoxin, fenofibrate
Saxagliptin (DPP-4 inibitors)

2. Adverse effects

Contrast

NSAIDs, COX 2 i, ACE, diuretics->tripple whammy

Aminoglycosides

Lithium

Calcinuerin

Question 15

Definition

Answer 15

1. eGFR <60 w/o signs of kidney disease or evidence of kidney damage-> albuminuria, hematuria, structural, pathalogical
2. Present for >3 months

Question 16

Screening test for CKD

Answer 16

1. urinary ACR measurement in a first void spot specimen=
   best measure for albuminuria,.not possible: can use
   random spot test–> repeat to confirm persistence
2. if abnormal need 2 of 3 abnormal readings over 3 months

Question 17

DIfferential for +ACR

Answer 17

UTI- dipstick, Acute febrile illness - T
+Dietary protein- Hx, ++exercise last
24 hours- Hx
Mensturation/vaginal discharge- Hx
NSAIDS- Hx, Congestive, cardiac failure

Question 18

Is eGFR clinically reliable

Answer 18

1. No, dependent on age
2. +muscle under, -ve muscle over
3. +Protein, vegetarian, creatine supplements interfere
4. Extremes of body size

Question 19

If abnormal eGFR

Answer 19

1. Urine ACR
2. eLFTs
3. Serum creatinine
4. FBC
5. Lipids, glucose
6. Urine MCS
7. Refer to neprhologist when GFR <30, drop in baseline 60
   by >5 over 6 months confirmed by 3 readings
   Glomerular hematuria w/ macroA
   CKD + HTN not ocntrolled despite three antihypertensive

Question 20

Management action plans: yellow, orange, red

Answer 20

1. Yellow >60 w/ microA, >40-59

Annual review:

a) exclude treatable, adress CVD, avoid nephrotoxic drugs
b) BP, lifestyle
c) Urine ACR, UEC, BUN, eGFR, HbA1C, statins
2. Orange 30-60 w/ micro >30-44

3-6 monthly

a) Same as yellow + detect complications, adjust medication doses, refer when indicated
b) +FBC, CMP, PTH when <45 + Urine ACR, UEC, BUN, eGFR, HbA1C, statins
3. Red action plan

MacroA, eGFR <30

1-3 monthly review

a) Same goals, + referall + prepare for dialysis + AHD
b) Same investigations + edema, +advanced care planning

Question 21

Stages

Answer 21

Stage 1: kidney damage with normal or increased GFR, ≥90 mL/minute/1.73m^2

Stage 2: kidney damage with mild decrease in GFR, 60 to 89 mL/minute/1.73m^2

Stage 3a: kidney damage with moderate decrease in GFR, 45 to 59 mL/minute/1.73m^2

Stage 3b: kidney damage with moderate decrease in GFR, 30 to 44 mL/minute/1.73m^2

Stage 4: kidney damage with severe decrease in GFR, 15 to 29 mL/minute/1.73m^2

Stage 5: kidney failure (end-stage kidney disease), with GFR <15 mL/minute/1.73m^2

Question 22

Define acute renal failure

Answer 22

Acute kidney injury is defined by a rise in the serum creatinine of ≥23 micromol/L (≥0.3 mg/dL) from baseline, a 50% increase in serum creatinine from baseline, or a reduction in urine output of <0.5 mL/kg/hour for more than 6 hours that occurs over a period of days to weeks.

Question 23

Counselling use of ACEi

Answer 23

1. Used to treat hypertension, block conversion of angiotensinogen to angiotensic 2, also inhibit bradykinin breakdown.
2. Avoid in pregnancy.
3. Common adverse effects: hypotension, headache, dizziness and cough. Also hyperkalemia, fatigue, nausea, renal impairment
4. Infrequently cause rash, angioedema, diarrhea and elevated LFTs
5. Cough is a persistent, non-productive. Not dose dependent, unlikely to respond. Some may need to stop.
6. May feel dizzy, get up slowly
7. Do not take potassium supplements, unless required.
8. when starting an ACE inhibitor:

stop potassium supplements and potassium-sparing diuretics

in heart failure, consider reducing dose or withholding other diuretics for 24 hours before starting an ACE inhibitor

review use of NSAIDs (including selective COX‑2 inhibitors)

start with a low dose

check renal function and electrolytes before starting an ACE inhibitor and review after 1–2 weeks