2.08 - CKD and AKI Flashcards
How is CKD classified according to GFR
G1: GFR>90
G2: GFR 60-89
G3a: GFR 45-59
G3b: GFR 30-44
G4: GFR 15-29
G5: GFR <15
How is CKD classified according to albumin : creatinine ratio
A1: ACR<3
A2: ACR 3-30
A3: ACR >30
What are the major causes of CKD
Hypertensive/diabetic/ischaemic neuropathy
Glomerulopathies
Inherited kidney disorders
Obstructive uropathy
Tubulointerstitial diseases
Nephrotoxic medications
What are the symptoms of CKD
Anorexia
Nausea
Fatigue + weakness
Muscle cramps
Pruitus
Dyspnoea
Oedema
What are the clinical signs of CKD
Pallor (Anaemia)
Hypertension
Fluid overload (JVP, oedema)
Skin pigmentation
Excoriation marks
Peripheral neuropathy
What are the indications for CKD testing
Diabetes
Hypertension
AKI
Obesity WITH metabolic syndrome
Cardiovascular disease
Structural renal tract disease
Proteinuria or persistent haematuria
Family history
What urine tests should be done to investigate CKD
Urine dipstick
Urine microscopy
ACR spot test
ACR 24 hour collection
Electrophoresis
What blood tests should be done to investigate CKD
FBC
U+E
Bone profile
PTH
Bicarbonate
LFT
Lipid profile
Autoimmune screen
Myeloma screen
What imaging should be done to investigate CKD
Renal ultrasound
MRangio
Echo
ECG
Why might a renal biopsy be performed in CKD
Identify intrinsic cause
What is the aim of renoprotective therapy
Slow CKD progression
Independent of aetiology
How is renoprotective therapy performed
Blood pressure control (<140/90)
Reduce proteinuria
Which patients should be offered a RAAS antagonist
Diabetic and have an ACR >= 3mg/mmol
Hypertensive and have an ACR >30mg/mmol
ACR>70mg/mmol
Why are RAAS antagonists not routinely used in CKD
ACE inhibitors are nephrotoxic
Why is dapagliflozin (SGL2 Inhib) used in CKD
Prevents reabsorption of filtered glucose in nephron
Reduces glucose in blood -> Reduces blood pressure
Inhibits RAAS -> Reduces blood pressure
When is dapagliflozin (SGL2 Ihib) recommended in CKD
eGFR 25-75 AND
T2DM OR ACR > 22.6
What other therapies are renoprotective
Statins
Smoking cessation
Antiplatelets (if secondary to CVS disease)
What are the common complications of CKD
Anaemia
Mineral + Bone disorders
Fluid overload
Acidosis
Hyperkalaemia
Why does CKD cause anaemia
Reduction in EPO production -> Decrease in erythropoiesis
What is the management for CKD induced anaemia
Erythropoietin stimulating agents (ESA) such as epoetin alfa
Patient must have adequate iron for it to be effective
Why should blood transfusions be avoided in CKD management
To minimise the risk of sensitisation to HLA in preparation for renal replacement therapy
Which medications most commonly cause hyperkalaemia in CKD
Potassium sparing diuretics
NSAIDS
What other CKD complication may worsen hyperkalaemia
Metabolic acidosis
How is acute hyperkalaemia treated
Calcium gluconate -> stabilise myocardium
Insulin / dextrose -> drive insulin into intracellular compartment
How is chronic hyperkalaemia managed
Low potassium diet
Potassium-binding resins
Correction of acidosis
Do i even need to ask you how CKD causes fluid overload robin is this really necessary
kidney fucked
blood not filtered right
too much gunk in the goo
fat legs
How is fluid overload managed in CKD
Oral diuretics
Reduced sodium intake
Fluid restriction
Why does CKD cause Acidosis
Retention of hydrogen ions due to abnormalities in acid-base homeostasis
May also exacerbate hyperkalaemia
How do you know someone has acidosis
Low pH and lo bicarb levels
What are the 3 forms of Renal Replacement Therapy
Haemodialysis
Peritoneal dialysis
Renal transplant
What is haemodyalisis
Blood passes through dialysis machine to filter it instead of the kidneys
Requires IV access via arteriovenous fistula or artificial line
What is peritoneal dialysis
The peritoneal cavity is used as the site of ultrafiltration
A catheter is used to insert dialysate into the peritoneal cavity
Peritoneum is used as semipermeable membrane
Dialysate is removed after a certain amount of time and procedure repeated
How often is haemodialysis performed
Multiple times per week for 3-4 hours
What are the two types of peritoneal dialysis
Continuous ambulatory (CAPD) - exchanges are made each day
Automated (APD) - exchange is done overnight while pt sleeps
What are the three types of donors who are able to give kidneys for RRT
Living donors
Donors after Cardiac Death (DCD)
Donors after Brain Death (DBD)
What must patients who receive renal transplants also be given
Long term immunosuppressive therapy to prevent rejection of donor tissue
Define Acute Kidney Injury (AKI)
Sudden decline of renal function over hours or days
What are the main causes of pre-renal AKI
Decreased circulating vol
Decreased cardiac output
Systemic vasodilation
Arteriolar changes
What are the main vascular causes of intrinsic renal AKI
Atherosclerotic disease
Thromboembolism
Renal artery stenosis
Malignant HTN
What are the two types of glomerular pathology associated with AKI
Primary - not associated with systemic disease, eg - glomerulopathy
Secondary - associated with systemic disease
What can cause tubulointerstitial pathology leading to AKI
Prolonged renal hypoperfusion
Medications (NSAIDs, PPIs, Penicillin)
Infections
What is the most common cause of post-renal AKI
Obstruction of the urinary tract
What are the risk factors for AKI
Age (>65)
Hx of AKI, CKD, HF, DM, Urological issues (infection, stones), Sepsis
Hypovolaemia
Nephrotoxic drug use
Contrast agents
What are the clinical features of pre-renal AKI
Reduced cap refill
Dehydration
Thirst
Dizziness
Reduced UO
Low BP
HF signs
What are the clinical features of intrinsic renal AKI
Depends on cause
Glomerular -> Sx of nephritic or nephrotic syndromes
Tubulointerstitial -> arthralgia, rashes, fever, eosinophilia
What are the clinical features of post-renal AKI
Loin-to-groin pain
Pain at site of obstruction
Haematuria
N+V
Prostatic obstruction -> dysuria
Bladder neck obstruction -> palpable bladder
What blood tests should be done to investigate AKI
Creatinine kinase
Vasculitis screen
Clotting
Blood film
Complement
Immunoglobulins
Serum electrophoresis
Virology (HepB and HepC)
What imaging should be done to investigate AKI
CXR - Heart failure
Renal dopplers - vascular assessment
MRI - vascular assessment
How is AKI managed
Stop nephrotoxic drugs
Fix volume dysregulation
Fix electrolyte abnormalities
List the nephrotoxic drugs
O DAMN
O - Opiates
D - Diuretics
A - ACEi + Antibiotics
M - Metformin
N - NSAIDs
