Chronic kidney disease Flashcards
Define CKD
DEFINITION: progressive loss of kidney function over a period of months or years
The definition is based on the presence of kidney damage or decreased kidney function (i.e. eGFR < 60 ml/min per 1.73 m2) for three months or more .
BMJ; Proteinuria or haematuria, and/or a reduction in the glomerular filtration rate, for more than 3 months’ duration.
Classify CKD by stages
○ Stage 1: Normal
• eGFR > 90 ml/min per 1.73 m2 with other evidence of CKD (microalbuminuria, proteinuria, haematuria, structural abnormalities, biopsy showing glomerulonephritis)
○ Stage 2: Mild Impairment
• eGFR 60-89 ml/min per 1.73 m2 with other evidence of CKD
○ Stage 3a: Moderate Impairment
• eGFR 45-59 ml/min per 1.73 m2
○ Stage 3b: Moderate Impairment
• eGFR 30-44 ml/min per 1.73 m2
○ Stage 4: Severe Impairment
• eGFR 15-29 ml/min per 1.73 m2
○ Stage 5: Established Renal Failure
• eGFR < 15 ml/min per 1.73 m2 or on Dialysis
Note; it can be classified by eGFR or by ACR (albumin creatinine ratio) -> above 3 is moderate. above 30 is severe
Explain the aetiology/risk factors of CKD
• In developed countries it is mainly associated with: ○ Age ○ Diabetes mellitus ○ Hypertension ○ Obesity ○ Cardiovascular disease
• Other risk factors: ○ Arteriopathic renal disease ○ Nephropathies ○ Family history ○ Neoplasia ○ Myeloma ○ Systemic disease (e.g. SLE) ○ Smoking ○ Chronic use of NSAIDs
Summarise the epidemiology of CKD
- COMMON
- Risk increases with age
- Often associated with other diseases (e.g. cardiovascular disease)
What are the causes of oedema in CKD?
Oedema is caused by reduction in GFR
Peripheral oedema is caused by reduction in serum albumin due to protein uria
What are the most common causes of CKD?
The most common causes are diabetes mellitus and hypertension.
What are the presenting symptoms of CKD?
The majority of people are asymptomatic, and the diagnosis is determined only by laboratory studies.
-> Presence of risk factors
-> Weakness and Fatigue
Headaches
Oedema
Oliguria
Incresed serum BUN:Creatinine ratio
Mild anaemia
Additional symptoms suggesting progression;
-> Anorexia (not eating)
-> Nausea with or without vomiting
- Pruritus
○ Peripheral oedema
○ Muscle cramps
○ Pulmonary oedema
• Sexual dysfunction is common
Recognise the signs of CKD on physical examination
- Physical examination rarely reveals many clues
- May show signs of underlying disease (e.g. SLE)
- May show complications of CKD (e.g. anaemia)
• Signs of CKD: ○ Skin pigmentation ○ Excoriation marks ○ Pallor ○ Hypertension ○ Peripheral oedema ○ Peripheral vascular disease
Investigations for CKD?
Serum creatinine - elevated Urinalysis - haematuria and or proteinuria Urine microalbumin - microalbuminuria Renal ultrasound - renal calculi eGFR estiomate - < 60ml/min
Renal biopsy - glomerulonephritis Serology ; - ANA - SLE • c-ANCA - granulomatosis with polyangiitis (Wegener's) • Anti-GBM - Goodpasture's syndrome Hepatitis and HIV serology
Got most of above from BMJ best practice - really good as it tells you expected outcome of result too (use for other conditions)
What are the principals of managing CKD?
Stage 1-4 no uraemia/anaemia;
- ACE inhibitor eg lisinopril OR ARB
- Statin
- 2nd line is CCB
Stage 5
- RRT eg Dialysis
- transplant
add furosemide if they develop fluid overload later
What is cystatin C and its use in CKD diagnosis?
Cystatin C is an alternative biomarker of renal function; due to muscle mass, it displays less variation than creatinine and offers greater accuracy of GFR estimation, which improves the relationship between eGFR and subsequent risk of CKD-related outcomes, such as cardiovascular death and end-stage renal failure.
You would prefer to use it over creatinine in;
stage 3a+ disease so egfr 59 and below
when do we consider referal to renal team in a pt with a reduced egfr?
complications of CKD?
Electrolyte disturbance; acidosis hypokalamia hyperphosphataemia -> cramps hypocalcaemia -> tetany, parasthesias
Bone profile:
2nd Hyper PTH
osteomalacia
Anaemia
Uraemia -> causes pericarditis and encephalitis
Fluid overload
Hypertension - due to innapropriate RAS activation
how do we manage uraemia in CKD?
depends on symptoms (not level of uraemia)
often just present with itching
if pericarditis or encephalitis -> dialysis
how would we manage hypertension in CKD?
ACEi - eg ramipril
usually need 2 of them
see y6 dropbox slides
https://www.dropbox.com/s/qza91tx6972atzw/Y6%20Renal%20History%20taking%20and%20Examination.pptx?dl=0
How does haemodialysis work? How often does it need to be done?
blood pumped out of the body via the vein in the AV fistula
blood circulates through the dialysis machine which has semi permeable membrane allowing exchange of toxins with the dialysate solution
this takes 4hours
should be done 3x per week
What is a Tesio line and how is it different to a normal central venous line?
A Tesio line is a double lumen central line. One lumen enters the right atrium, the other
sits outside the RA in the vena cava. The line is tunneled under the skin to the lateral
right chest where it exits the skin.
The main difference can be seen clinically at the skin
exit point. With a central line, only 1 line enters the skin, it bifurcates into two lumens
outside the body. With the Tesio, there is no bifurcation, two lumens enter the skin.
When removed, it leaves a scar that looks like a vampire fang bite
two circles next to each other or a straight scar if the two holes merge when pulling it out.
3) What is an arteriovenous fistula and how does it work?
AV fistulas are a connection between an artery and a vein. Usually done by a vascular
surgeon in the forearm.
After being formed, they take upwards of six weeks to mature. This process is known as
fistula maturation. The turbulent blood in the fistula also generates the palpable pulsatile thrill
and bruit than can be auscultated. The presence of both thrill and bruit indicates fistula
patency
4) How does peritoneal dialysis work? How often does it need to be done?
dialysis solution introduced into the peritoneal cavity and left for some time
this allows natural exchange of toxins into the dialysate
the fluid is then removed
done daily -> 1-4 times depending on type - in sleep or during day.
continuous ambulatory PD (CAPD) - 4x pd
This is different to automated PD - 1x at night
5) What are the risks/benefits of each type of dialysis?
Haemodialysis;
Risks; blood infection, thrombosis, done in clinical setting
Note; must make dietary changes
Peritoneal dialysis;
Better tolerated, less expensive, can be done at home
Risks; abdominal infections,
Note; patient has to be able to care for themselves or have family/carers to help. If hx of lots of abdominal surgery, cant have this.
https://www.dropbox.com/s/t825yy3acgupqu3/Y6%20Renal%20Exercises%20-%20Qs%20and%20Answers.docx?dl=0
6) What are the risks of a fistula vs a Tesio line
Fistula;
may not mature, may fail, may stenose or lose patency, low risk of
infection, can be damaged, unsightly, takes time to mature 6-8wks
Tesio; needs replacing every few years, risk of line sepsis/infection, easier to
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