Lecture 10 - renal diseases Flashcards
What is the primary function of the kidneys?
Regulation of water and electrolytes, acid/Base balance, waste excretion, blood pressure control, and hormone secretion (erythropoietin, vitamin d, renin)
List the major factors associated with CKD progression according to the 2021 NICE guideline
increasing age, cardiovascular disease, proteinuria, previous AKI, hypertension, diabetes, smoking, African/african-caribbean or asian family origin, chronic NSAIDs, untreated urianry outflow tract obstruction
How is renal function commonly measured?
cockcroft gauld - uses IBW, age, and weight. use correction factor 0.4 + IBWif obese. limitatiosn are if patient is in catabolic stress, extensive oedema, very poor or good renal fucntion, rapidly changign rena fucntion, pregannt women or children and icnreased creatine consumption.
eGFR - uses age, race, BSA, gender, albumin. limitations are if patient has a transplant, serious comorbidiotes eg diabetes, all races, very poor or good renal fucntion, rapidly changign renal fucntion, pregnant women or children and icnreased creatine consumption
what is renal disease ?
renal disease can be acute or chronic kidney disease. eGFR, CrCl and CKD-EPI can all be used to estimate the severity. we don’t just look at the current serum CR - need to look at a trend for what is normal for the patient
chronic kidney disease - what is it, who is at risk and how do we manage it ?
chronic kidney disease is deteriorating progression, irreversible loss of kidney function, that may require renal replacement therapy. people at risk are: diabetes, HTN, AKI, CVD, structural renal disease tract, Polycystic kidney disease, Glomerulonephritis, family history of ESRD, opportunistic detection of haematuria, longterm nephrotoxic medication - ciclosbrin, NSAID etc, covid 19 infection.
what can we do - Accurate diagnosis, monitor & treat underlying causes
✅ Prevent progression:
ACE inhibitors, ARBs, SGLT2 inhibitors
Lifestyle advice
Aggressive BP control
✅ Preserve kidney function: avoid nephrotoxins
✅ Control symptoms
✅ Manage cardiovascular risk:
BP target <140/90 (<130/80 if diabetic/proteinuria)
Consider statin
what should be considered when starting an ace inhibitor in renal of CKD
ACE inhibitors or an ARB slows renal function even in advanced CKD. there may be an initial fall in eGFR up to 30%. check the bloods initially and after dose changes. there is more likely to be a decline in GFR due to volume depletion eg on high dose diuretic. the main caution is bilateral renal artery stenosis and hyperkalaemia. Must remember SICK day rules.
describe SGLT2 inhibitors in renal disease and safety advice
SGLT2 inhibitors improve cardiac control, renal outcomes and glycemic control.
safety advice - the tibial fall in eGFR can be up to 30%. SGLT2 inhibitors have a risk of diabetic ketoacidosis, and mycotic genital infections. requires caution if patient is dehydrated, has UTIs or peripheral vascular disease.
what are they intervention for CKD management
Accurate diagnosis, preventing progression with ACE inhibitors, ARBs, and SGLT2 inhibitors, symptom control, and lifestyle modifications.
What are some biological actions altered in CKD that impact medication management?
Hypovalameia: enhanced antihypertensive effects. start at low dose and increase to max.
Hyperkalaemia: increased side effects with ace inhibitors and potassium salts
uraemia: can cause excess bleeding
enhanced sensitivity to centrally acting eg analgesics especially morphine - start at lower doses.
variation in electrolytes eg digoxin toxicity
what are drugs used to treat hyperkalaemia ?
Patiromer 16.8 g once daily or Lokelma – 5-10 g x 1-3 daily
Calcium Resonium – 15 g x 3 daily (o), 30 g (PR)
Salbutamol Nebules – 5 mg x 4 daily
Calcium Gluconate 10% - 30 mls over 5-10 mins
Insulin/Dextrose – 8 units actrapid in 100 mls 20% dextrose over 15 - 30 mins
Sodium Bicarbonate 1.26%, 500 mls - over 1 hour
what are drugs that you must take care with
Low therapeutic window drugs
Drugs that are really excreted for example, aminoglycosides and vancomycin
Active metabolites which are really excreted for eg morphine
antibiotics especially cephalasporins and penicillins. lower dose is required as nephrotoxic. ciprofloxacin and macrolides can cause nausea if the dose is too high.
antiviral eg acyclovir need to be drastically reduced otherwise very nephrotoxic and will cause nausea
what are hyperparathyroidism causes
reduced phosphate excretion, reduced calcium absorption, reduced calcitriol production by the kidney, uraemia reduces sensitivity of parathyroid gland to calcium, inhibitors of binding oc calitriol to receptor in parathyroid gland
what are CKD mineral and bone disorders?
hyperparathyroidism, osteomalacia, dynamic bone disease, osteoporosis
what are secondary causes of hyperparathyroidism?
Secondary causes of hyperparathyroidism are reduced phosphate excretion, reduced calcium excretion, reduced calcitriol production from the kidneys, uraemia reduces sensitivity of parathyroid gland to calcium, and inhibiting of binding of calcitriol to receptors to the parathyroid gland.
what are symptoms of raised calcium or phosphate product
pruritic, conjunctival calcification, bone pain, skeletal deformity, increased risk of fractures
what are treatment option of raised phosphate or calcium
diet - food rich in protein
phosphate binders, vitamin D and cinacelet
control of aluminium levels
Surgery
give examples of phosphate binders
calcium based - calcichew , calcium acetate
heavy metal based - lanthanum carbonate
iron based - velphoro
polymer based - sevelamer carbonate and hydrochloride
What are the treatment options for CKD-related Mineral and Bone Disorder (CKD-MBD)?
Vitamin D analogues: Alfacalcidol (1α-hydroxycholecalciferol, oral/IV), Calcitriol (1,25-dihydroxycholecalciferol, oral), Paricalcitol (vitamin D analogue, oral/IV).
Calcimimetics: Cinacalcet (oral), Etelcalcetide (IV).
what are the causes of renal anaemia ?
Lack of erythropoietin production
Iron deficiency (TSATS > 20, Ferritin: 200-500)
Increased red blood cell breakdown due to uraemia
Blood loss
Hyperparathyroidism
Aluminium toxicity
Infection or Inflammation
Inadequate dialysis
what are symptoms of anaemia ?
Fatigue
Breathlessness
LVH
Impaired cognitive function
Loss of libido
Decreased cold tolerance
Treatment of anaemia
ESA’s e.g. Epoetin alfa, beta & zeta, Darbepoetin, Mircera – SC/IV
HIF-Inhibitors e.g. Roxadustat – oral option
IV Iron: e.g. iron sucrose, iron dextran, Ferinject, ferric derrisomaltose
Oral iron (not at same time as phosphate binders)
Renal Replacement Therapy Modalities
Haemodialysis (HD) / Haemodiafiltration (HDF)
Haemofiltration – mainly done in ICU
Peritoneal dialysis – CAPD, APD
Transplantation
Conservative care
What are some common problems associated with HDF (Hemodiafiltration)?
Hypotension (“crash”) - 25-60%
Cramps - 5-25%
Itch - 1-5%
Clotting & blocked lines
Nausea & vomiting - 5-15%
Exhaustion
Anaemia
Hair loss
Infections
Issues with dementia patients - confusion, pulling needles/lines out
Restless legs
Boredom
what are risk factors for AKI
Increasing age
Diabetes
CKD
Cardiac failure
Dehydrated
On more than 1 nephrotoxin
Chronic liver disease
People with reduced renal blood flow
what are signs and symptoms of an Aki ?
reached urinary output, dehydration or thirst, SOB, fatigue, confusion or drowsiness, coma if severe, abdominal pain, nausea or vomiting, swelling in legs, ankles or around eyes
what is are physiological and nephrotoxins of pre renal failure
type of AKI
physiological causes are
volume depletion,fluid loss, reduced CO, vascular insufficiency and hepatic failure
nephrotoxicity - drugs
ciclosphpirs, laxative, ace inhibitors, diuretics, NSAIDs, beta blockers high dose dopamine
what is pre renal failure ?
