14 - Renal Medicine Flashcards
What are the different ways that renal disease can present?
1. Asymptomatic: non visible haematuria, asymptomatic proteinuria, abnormal eGFR, HTN, electrolyte abnormalities
2. Renal tract symptoms: urinary symptoms, loin poin, visible haematuria, nephrotic syndrome, symptomatic CKD
3. Systemic disorder with renal involvement: DM, sickle cell, SLE, infection, malignancy, pregnancy, drugs
How do you take a renal history?
- If being dialysed ask them what mode, what access and when they were last dialysed
- Important to ask if NSAIDs being taken OTC
How do you perform a renal examination on a patient?
https: //www.youtube.com/watch?v=PPhwQgsebKY
- General inspection
- Hands
- Arms
- Face
- Chest
- Abdomen
- Legs and Sacrum
- Further tests
What are some of the different modes of renal replacement therapy?
- APD (Automated peritoneal dialysis via peritoneal catheter)
- CAPD (Continuous ambulatory peritoneal dialysis)
- Assisted PD (Can perform at home with help of district nurses)
- UHD (Unit based haemodialysis)
- HHM (Home haemodialysis)
What are the different ways of access for dialysis? (both peritoneal and haemodialysis)
- PD catheter
- AV fistula
- Tunelled (Perm-Cath)
- Non-Tunelled (Vas-Cath)
What are some signs on examination of advanced renal disease?
- Brown nails
- Yellow brown uraemic skin
- Uraemic frost from sweat on skin
- Hyperreflexia
- Pericardial rub
What are some different renal function tests?
Bloods: FBC, U+Es, bone profile, CRP, HbA1c
Urine: dipstick, protein-creatinine ratio, albumin-creatnine ration, urine culture
Imaging: US KUB
How does a metabolic alkalosis show on a VBG and what are some causes of this?
- GI losses: vomiting and diarrhoea
- Renal losses: primary hyperaldosteronisms, diuretics
- Intracellular shift: hypokalaemia
How does a metabolic acidosis show on VBG and how can you work out the cause?
Anion Gap!!!!
Na - (Cl + HCO3)
Normal is 8-12
What is the cause of the derangment of this patients blood gas?
What are some of the symptoms of hypernatraemia and what is the number one cause of this electrolyte abnormality?
Thirst, irritability, weakness, confusion, seizures, hyperreflexia, spasticity, coma
Usually due to dehydration which causes cellular dehydration and vascular shear stress so bleeding and thrombosis
What are some causes of hypovolemic, euvolemic and hypervolemic hypernatraemia?
Hypovolemic: vomiting, diarrhoea, diuretics, osmotic diuresis
Euvolemic: diabetes insipidus, hypodipsia, inadequate water intake, heatstroke
Hypervolemic: hypertonic dialysis, sodium bicarbonate administration, hypertonic saline administration, hyperaldosteronism, Cushing’s
What are some causes of central and nephrogenic diabetes insipidus?
Central (impaired release of ADH)
- Trauma
- Tumours
- Cerebral sarcoid/TB
- Infection e.g meningitis
- Cerebral vasculitis e.g SLE
Nephrogenic: (resistance to ADH)
- Congenital
- Drugs (lithium, amphotericin)
- Hypokalaemia
- Hypercalcaemia
How is hypernatraemia managed?
Free water
What are some of the symptoms of hyponatraemia?
- Headache
- Decreased perception
- Confusion
- Seizures
- Gait disturbance
- Reversible ataxia
- Nausea
What is pseudohyponatraemia?
- Sodium <135 but with a normal serum osmolality
- Due to either high lipids, myeloma, hyperglycaemia, uraemia
What are some causes of hypovolemic, euvolemic and hypervolemic hyponatraemia?
Hypovolemic: diuretics (thiazides), osmotic diuresis, Addison’s disease due to mineralcorticoid deficiency, diarrhoea
Euvolemic: Hypothyroidism, Glucocorticoid deficiency, SIADH
Hypervolemic: CCF, nephrotic syndrome, liver cirrhosis, renal failure
What are some investigations you should do when a patient has hyponatraemia?
- Plasma osmolality: rule out pseudohyponatraemia
- K+ and Mg2+: hypoK and hypoMg can potentiate ADH release
- Urine Na: if <20 then non-renal salt losses, if >40 then SIADH
- TSH and 9am Cortisol
- Calcium, Albumin, Glucose, LFTs
- CT head if suspect SIADH
How do you diagnose SIADH?
- Hyponatraemia with low serum osmolality
- Urine osmolality >100 with urine Na>20
- Euvolemia
- Not on diuretics
PROCESS OF ELIMINATION: normal renal, thyroid and adrenal function
What are some causes of SIADH?
- Malignancy
- Meningitis
- Subarachnoid haemorraghe
- Drugs e.g SSRIs, morphine, amitriptylline
- Hypothyroidism
What is the management for SIADH?
- Fluid restrict: <800mls day
- Furosemide
- Demelocycline or Tolvaptan to induce ADH release (can reverse too far to DI)
- PO NaCl
What is the management of hypovolemic and hypervolemic hyponatraemia?
Hypovolaemic: (renal or GI losses of Na) IV fluids 0.9% NaCl at 1-3ml/kg/hr and add K+ if needed
Hypervolaemic: (increased water lowering Na) fluid restrict and consider furosemide
Why should you not correct hyponatraemia rapdily?
Risk of central pontine myelinolysis, correct by <12 mmol/day
How should acute and chronic hyponatraemia be managed?
Acute and Symptomatic (<48hours)
- 3% HYPERTONIC SALINE BOLUSES +/- Furosemide)
Chronic and Symptomatic (>48 hours)
- If seizures hypertonic saline boluses
- Otherwise isotonic saline and furosemide
Chronic and Asymptomatic
- Water restriction
- Stop offending drug
- If dehydrated give water
- If fluid overloaded give water restriction, furosemide and Na
What drugs can cause hyperkalaemia?
- ACEi/ARBs
- Spironolactone
- Amiloride
- NSAIDs
- Heparin
- Trimethoprim
- Betablockers
What are some causes of hyperkalaemia?
- CKD/AKI
- Drugs (ACEi, spironolactone, NSAIDs, etc)
- Hypoaldosteronism
- Addison’s disease
- Rhabdomyolysis
- Metabolic acidosis e.g DKA
- Hyperkalaemic periodic paralysis
What are some causes of artifact hyperkalaemia?
- Haemolysis
- Raised WCC
- Raised platelets
What can hyperkalaemia do to the pH of the blood?
Metabolic acidosis
When is a patient having Type IV RTA and what are some common causes of this?
Due to issue with distal tubule not being able to respond to aldosterone
- Hyperkalemia
- Hypochloraemic metabolic acidosis
- HTN
Causes: hyporeinaemic hypoaldosteronism, diabetic nephropathy, hypertension, NSAIDs, lupus nephritis
How is hyperkalaemia due to type 4 RTA treated?
- Low K diet
- Fluid restrict
- Loop diuretic if overloaded
What are some ECG changes with hyperkalaemia?
- Tented T’s
- Prolonged QRS
- Slurring ST segment
- Loss of p waves
- Sine then asytole
What is the first investigation you should do when a patient has hyperkalaemia on their blood results?
- VBG to check correct
- ECG to look for changes
How is hyperkalaemia with ECG changes treated?
Stabilise myocardium to prevent arrhythmias: 10mls of 10% Calcium Gluconate over 5-10 minutes
Shift potassium back into extracellular space: IV fast acting insulin with glucose or Salbutamol neb
Eliminate potassium from body: Calcium resonium
Dialysis: if treatment resistant
What are some of the symptoms of hypokalaemia?
- Fatigue
- Constipation
- Proximal muscle weakness
- Poor glucose control
- Cardiac arrhythmias
What are some of the causes of hypokalaemia?
- Poor intake
- Gut losses e.g vomiting, NG losses, ileostomy
- Drugs e.g alpha blockers, beta agonists, insullin, theophylline
- Refeeding syndrome
- Conn’s syndrome (Primary hyperaldosteronism)
- Cushing’s syndrome
- Diuretics
- Hypomagnesiumaemia