CKD Flashcards
how common is CKD?
1/8 people will have CKD
50% of people aged over 75 years will have CKD
What is the definition of CKD?
CKD is defined as abnormalities of kidney structure or function present for >3 months with implications for health.
Criteria for CKD: any of the following present for > 3 months
1) markers of kidney damage:
- albuminuria (ACR greaterthanequal to 30 mg/g)
- urine sediment abnormalities
- electrolyte and other abnormalities due to tubular disorders
- abnormalitites detected by histology
- structural abnormality detected by imaging
- history of kidney transplatation
2) decreased GFR –> Less than 60 ml/ min/ 1.73 m2
What investigations are required to confirm CKD?
Urine dip –> proteinuria
bloods –> u and E’s, eGFR
Imaging –> renal USS, structural abnormalities
Special tests –> urine ACR (albumin creatinine ratio, PCR protein creatinine ratio, lab confirmed protein or albuminuria, renal biopsy, histology of renal disease).
What are we looking for in the U and E’s for renal function?
what is the main component in U and E’s that is of importance?
How can muscle mass affect this component?
How can this component be used to estimate GFR?
What is normal GFR?
Renal function blood test = U and E’ s –> urea, creatinine, sodium, potassium
creatinine is looked at for chronic kidney disease.
Creatinine is a waste product of muscle breakdown; exclusively excreted by the kidneys.
Normal creatine levels are altered by age, weight, race and gender which all affect muscle bulk
(i.e. body builder will have high creatinine in the blood purely due to muscle breakdown, could falsely give the appearance of malfunctioning kidneys, vs amputee with low muscle mass and injured kidney masking kidney injury).
Creatinine = marker of renal function: if kidney’s arent clearing it then nobody else is
Glomerular filtration rate calculated from creatinine with age/ race/ weight and gender.
Normal GFR = greater than 90
How CKD staged?
- Stage 1 –> kidney damage with normal kidney function, GFR 90 or higher, 90-100% normal kidney function
- Stage 2–> kidney damage with mild loss of kidney function, GFR 60-89, % of kidney function 89-60%
- Stage 3A –> mild to moderate loss of kidney function, GFR 59 to 45 and % of kidney function
- Stage 3B –> moderate to severe loss of kidney function; GFR/ renal function 44-30%
- Stage 4 –> severe loss of kidney function; GFR/ kidney function 29-15%
- Stage 5 –> kidney failure –> GFR/ Kidney function less than 15%
What are the causes of CKD?
Most common cause if Type 2 diabetes
HBP
Glomerular diseases
Type 1 diabetes
Cystic hereditary
nephritis
tumours
What investigations should be done when identifiying the cause of CKD?
- Bedside investigations:
- urine dipstick
- protein or blood
- query nephritis or nephropathy
- blood pressure –> query HTN
- Bloods:
- HBA I C (HbA1c is your average blood glucose (sugar) levels for the last two to three months) –> diabetes
- Imaging:
- renal USS —> structural abnormality or tumour
- Special tests:
- Renal screen –> PSA (prostate may obstruct bladder), protein electrophoresis/serum light chains (myeloma) , vasculitis –> ANA, complement, MPO/PR3/ANCA antibodies (antineutrophil cytoplasmic AB’s for vascular inflammatory disorder), anti GBM (antiglomerular basement membrane) and blood borne viruses e.g. hep A/ HIV.
- renal biopsy –> histology to confirm other investigations
signs and symptoms of chronic kidney disease:
- aches and pains/ anorexia/ arrythmia
- encephalopathy
- fraactures
- HTN
- lethargy
- nausea
- pruritus (severe itching of skin) / pericarditis
Approach to kidney disease?
- function of kidney
- what happens when this goes wrong –> signs, symptoms, investigations to confirm
- how can we put this right –> management
What are the functions of the kidney?
A WET BED
A –> acid base balance
W -> water removal
E –> erythropoetin production
T -> toxin removal
B -> blood pressure control
E –> electrolyte balance
D –> vitamin D activation
What are the signs/ sx/ investigations/ management when water removal function goes wrong?
Signs –> peripheral oedema, pulmonary oedema
Symptoms –> swelling, SOB, nocturia
Investigations –> N/A
Management –> fluid restriction, diuretics, renal replacement therapy
What are the signs and symptoms of toxin removal gone wrong?
(main sx being Uraemia, High blood urea/ other nitrogenous waste compounds normally removed by kidneys )
Signs –> encephalopathy, pericarditis, bleeding tendency
Symptoms –> nausea, vomiting, hiccups (irritative), neuropathy, pruritis (itching) , malaise (tiredness)
investigations –> U and E ‘s
Management – >renal replacement therapy
What are the signs/ sx/ investigations/ management when BP control is lost?
Signs –> HTN urgency
Symptoms –> headache, visual disturbance
investigations –> blood pressure monitoring
management –> antihypertensives, renal replacement therapy
What are signs/ sx/ investigations/ management of acid base balance loss?
Signs –> N/A
symptoms –> anorexia, lethargy
Investigations –> metabolic acidosis: pH on ABG, HCO3-
management –> PO or IV sodium bicarbonate
Renal replacement therapy
What are the signs/ sx/ investigations/ management of of EPO production loss?
Signs –> pallor
Sx –> SOB, chest pain, lethargy
Investigations –> Full blood count : low Hb
Management : EPO replacement, blood transfusion
What are the signs/ symptoms/ investigations and management of loss of electrolyte balance (hyperkaleamia)?
Signs –> pulse –> irregularly irregular
Symptoms – >palpitations
Investigations –> ECG, U and E’s
Management –> Low potassium diet, renal replacement therapy
what are the signs, symptoms, investigations and management of loss of vitamin D activation?
Signs –> osteomalacia, high phosphate, hypocalcaemia
Symptoms -> aches and pains, bone deformities, fractures
Investigations -> calcium, phosphate, vitamin D, parathyroid hormone
Management –> phosphate binders, calcium replacement, vitamin D replacement, calcitonin
What bedside tests could you do to look for the complications of CKD?
- Blood pressure –> HTN
- Fundoscopy –> hypertensive retinopathy?
- ECG –> arrythmias?
What should you look for in bloods to check for complications of CKD?
- U & E’s –> eGFR to check severity of kidney decline, hyperkalemia, uraemia
- FBC –> anaemia
- clotting –> ureamia
- bicarb and pH –> acid base balance
- calcium, phopshate, vitamin D, PTH
what imaging can be done to look for complications of CKD?
Xrays – >fractures and osteomalacia
What are some of the management steps for CKD?
- low potassium diet - damaged kidneys allows potassium to build up
- fluid restriction - both due to fluid build up and to allow haemodialysis, as dialysis machine will not be able to remove excess fluid from the blood if the individual drinks too much. Amount allowed to drink is based on weight (1000-1500ml/day)
- Renal replacement:
- haemodialysis
- peritoneal dialysis
- renal transplant
What is included in renal replacement therapy?
When is this done?
- haemodialysis
- periotoneal dialysis
- renal transplant
Done when eGFR is below 15 = kidney failure
What is haemodialysis?
Filtration of the blood - creation of an ateriovenous fistula (connection between artery and vein), fast running blood running through a vein on the surface of the skin. For dialysis need access to blood supply that is quite fast running, hence why they create arteriovenous fistula.
Blood is diverted through two needles inserted into the AV fistula, one needle removes blood and transfers it to the dialysis machine which filters waste products from the blood, the filtered blood is then passed back into the body via a second needle.
Most individuals need 3-4 sessions of haemodialysis a week.
Can also be done through a dialysis line or central line (type of central venous catheter) which is tunned out to the skin.
What is periotoneal dialysis?
- This is less commonly seen, done at home.
- uses the periotenoeum as the filter, fluid is put into the perioteneal cavity, peritoneum acts as a filter all the excess fluid and electrolytes/ waste cross the periteoneum into the peritoneal cavity, then is drained and removed.
- Need access to the perioteoneum via periteonal access catheter - surgery
- need peritoneal dialysis machine, normally done at nightime at home
*
Renal transplant - where can kidneys come from?
Where does the transplanted kidney go?
What does a patient need to go on after?
- Kidney may come from deceased donor or living donor
- Tranplanted kidneys go into the pelvic cavity
- Good thing about living donor is you can plan in advance
- negatives - surgery which always carries risk, can become unwell post surgery or it could be rejected/not work
- need to be on lifelong immunosuppression (risk of infection and cancer)
What are the advantages/ disadavantges of renal replacement therapies?
