Computer generated transcript

Warning!
The following transcript was generated automatically from the content and has not been checked or corrected manually.

Y4 RENAL TUTORIAL Jane Yi Chiam, Y5 Medical StudentLearning Objectives ● Renal Physiology ● AKI ● CKD ● Fluid Balance & PrescriptionRENAL PHYSIOLOGYWhat do the kidneys do? A WET BED A Acid-base balance W Water balance E Electrolyte balance T Toxin removal B Blood pressure control E Erythropoietin production D Vitamin D metabolismACUTE KIDNEY INJURYAcute Kidney Injury (AKI) ● Abrupt reduction in renal function due to insult to kidneys ○ Rise in serum creatinine ≥26 µmol/l within 48 hours ○ Rise in serum creatinine ≥50% (1.5x baseline) in last 7 days ○ Urine output <0.5ml/kg/hr for ≥6 hours ● Common in hospitalised patients Sudden rise in Low urine output serum creatinineKDIGO Staging of AKI Staging Serum creatinine Urine output Stage 1 1.5-1.9x baseline <0.5ml/kg/hr fo≥6 hours or Increase by≥26 µmol/l Stage 2 2.0-2.9x baseline <0.5ml/kg/hr fo≥12 hours Stage 3 ≥3.0x baseline <0.3ml/kg/hr fo≥24 hours or or Increase by ≥353.6 µmol/l Anuria fo≥ 12 hoursRisk Factors ● Age >65 years ● Comorbidity ○ CKD ○ Hypertension ○ Diabetes ○ Heart failure ○ Liver disease ● Medications ○ ACEi/ ARBs ○ NSAIDs ○ Diuretics ○ Antibiotics & antimicrobials (e.g. aminoglycosides)Causes ● Hypotension - infection/ sepsis ● Hypovolaemia - GI losses, haemorrhage, diuretics Pre-renal ● Reduced cardiac output - e.g. heart failuresion ● Renovascular disease - e.g. renal artery stenosis, aortic dissection ● Acute tubular necrosis - pre-renal injury (prolonged), rhabdomyolysis, drugs (aminoglycosides, vancomycin, contrast) ● Acute interstitial nephritis - drugs (NSAIDs, PPI, pe icillin) Renal ● Glom-ruglomeruli/ r nal tubules/ interstitium ● Intrarenal vascular injury - vasculitis, SLE, emboli ● Myeloma ● Bladder outflow obstruction - BPH, tumour/ malignancy ● Ureteric obstruction (usually bilateral) ○ Kidney stones Post-renal Anything that blocks urine flow ○ Intrinsic tumour ○ Ureteral strictures No specific symptoms/ signs! Symptoms Signs ● Oliguria/ anuria ● Peripheral oedema ● Confusion/ delirium ● Pulmonary oedema - chest ● Nausea crackles ● Symptoms of underlying cause ● Raised JVP ○ Vomiting ● Haematuria ○ Diarrhoea ● ProteinuriaInvestigations ● U&E - urea, creatinine, electrolytes (Na, K) ● FBC, CRP, infection screen (cultures/ swabs/ sputum) ● Urine output Raised urea:cr ratio = pre-renal AKI ● Urine dip + urinalysis ○ Urea : creatinine ratio Brown casts = Acute tubular necrosis ○ Microscopy Red casts = Glomerulonephritis White casts = Acute interstitial nephritis ● Imaging ○ Ultrasound - renal tract, bladder scan ○ CT scan ● Specific blood tests ○ Autoantibodies - ANCA, dsDNA, anti-GBM ○ Myeloma screen - serum & urine electrophoresisManagement (1) ● Manage fluid balance ○ Catheterise & fluid balance chart ○ Replace fluids if hypovolaemic - 500ml 0.9% NaCl IV over 15mins ● Manage hyperkalaemia (K+ >6.5 or ECG changes) - risk of arrhythmias! ○ IV calcium chloride/ gluconate - stabilise cardiac membrane ○ IV insulin-dextrose - intracellular uptake of K+ ○ Oral calcium resonium - removes K+ from body ● Review medications! ○ Stop nephrotoxic drugs - NSAIDs, ACEi/ARBs, diureticsManagement (2) ● Treat underlying cause ○ Pre-renal: correct volume depletion/ improve renal perfusion ○ Renal: refer for specialist treatment of intrinsic renal disease ○ Post-renal: catheter, refer to urology ● Refer to renal for RRT (e.g. haemodialysis) if indicated ○ AKI not improving ○ Refractory hyperkalaemia/ acidosis ○ Oedema, volume overload (& not responsive to initial Rx) ○ Uraemia - encephalopathyCHRONIC KIDNEY DISEASEChronic Kidney Disease (CKD) Definition ● Abnormalities of kidney structure/ function for >3 months ○ GFR <60 ○ OR markers of kidney damage, including albuminuriaCKD Classification 1. GFR Stage eGFR (ml/min/1.73m ) Notes 1 >90 Normal GFR. CKD only if other evidence of kidney damage: abnormal urinalysis/ histological changes on biopsy 2 60-89 Mild CKD. CKD only if other evidence of kidney damage: abnormal urinalysis/ histological changes on biopsy 3 30-59 Moderate CKD 4 15-29 Severe CKD 5 <15 End-stage renal damageCKD Classification 2. Cause (see next slide) 3. Albumin : creatinine ratio (ACR) Normoalbuminuria <30 Microalbuminuria 30-300 Macroalbuminuria >300Causes of CKD ● Diabetes (commonest!) ● Hypertension ● Incomplete recovery from AKI ● Polycystic kidney disease ● Chronic interstitial nephritis - many causes ● Chronic glomerular disease - many causesSymptoms & Signs ● Often asymptomatic until advanced CKD - picked up incidentally ● Polyuria, nocturia ● Fluid retention - ankle swelling ● Symptoms/ signs of anaemia ● Fatigue ● Pruritus, nausea, loss of appetite (secondary to uraemia) ● Encephalopathy (secondary to uraemia) → flapping tremor - Kidney transplant scar (RIF/LIF) - Palpable mass near/ under scar AV fistula for dialysis - looks like a lumpInvestigations 2+ 3- ● Bloods - U&E, Hb, glucose, ↓Ca , ↑PO , 4PTH ○ Specific bloods - ANA, ANCA, anti-GBM ● Urine - dipstick, MC&S, albumin:creatinine ratio, Bence Jones (myeloma) ● Imaging ○ USS - size, symmetry, anatomy of kidneys ● Renal biopsy if indicatedManagement of CKD ● Treatment to slow CKD progression ● Treat complications of CKD ● Monitor rate of CKD progression - eGFR & A:CR at least annually ● Refer to nephrology ○ Stage 4 or 5 CKD ○ Moderate proteinuria (A:CR >70)/ A:CR >30 with haematuria ○ Declining eGFR/ rapid rise in creatinine ○ Poorly controlled hypertension despite being on 4 antihypertensives ○ Known/ suspected genetic or rare causes of CKD ● (Dialysis) ● (Kidney transplant)Management to slow CKD progression ● BP control ○ If A:CR <70, target <140/90; if A:CR >70, target <130/80 ● Glycaemic control ○ Target HbA1c of 53 mmol/mol, unless risk of hyopglycaemia ● ACEi/ ABRs ○ DM & A:CR >3 ○ Hypertension & A:CR >30 ○ Any CKD with A:CR >70 ● Cardiovascular health ○ Statins ● Lifestyle ○ Exercise, healthy weight, smoking cessation, salt intake <2g/dayComplications of CKD ● Hypertension - maladaptive RAAS ● Hyperkalaemia - managed same as AKI ● Acidosis - consider sodium bicarbonate ● Anaemia ● Bone disease (renal osteodystrophy) ● Cardiovascular disease - statins ● MalnutritionComplications of CKD - Anaemia ● Reduced erythropoietin production → reduced RBC production ● Management ○ Target Hb 100-120 g/L (cutoff is usually 110 g/L) ○ Oral iron ○ IV iron if target Hb not reached within 3 months ○ EPO/ ESA (erythropoietin stimulating agent)Complications of CKD - Bone Disease ● Reduced vitamin D (reduced 1-alpha hydroxylation of calcifediol to vit D) ○ Low vit D → reduced Ca absorption in gut → increased PTH release (secondary hyperparathyroidism) ○ PTH causes osteoclast-mediated bone resorption → increased fracture risk ○ Renal oesteodystrophy ● Reduced phosphate excretion → high phosphate → reduced calcium ● Management ○ Reduced dietary intake of phosphate ± phosphate binders ○ Vitamin D supplements if deficientFLUID BALANCEFluid Balance Assessment ● History Euvolaemic ● BP, pulse, respiratory rate, O2saturation, temp. ● Capillary refill time ● Skin turgor - back of hands, sternum Hypovolaemic ● Mucous membranes - lips, tongue ● JVP - normal is 2-3cm ● Heart sounds - HS III may indicate fluid overload ● ?pleural effusion, ascites, oedema Hypervolaemic ● Drug chart ● Fluid chart - input, output, weightFluid Balance Assessment Hypovolaemic Hypervolaemic ● Thirst ● Ankle swelling ● Tachycardia ● Pulmonary oedema ● Low BP, dizziness ● Pleural effusion ● Prolonged CRT ● Breathlessness ● Reduced skin turgor ● Abdominal swelling/ ascites ● Dry mucous membranes ● Raised JVP ● JVP not visible ● Hypertension ● Oliguria ● Weight gain ● Weight loss ● Elevated urea & creatinineFluid Types Resuscitation Fluids Maintenance Fluids ● 0.9% sodium chloride ● 0.18% sodium chloride/ 4% glucose ● Plasmalyte ● 5% glucose ● 0.9% sodium chlorideNormal Requirements ● Fluid requirement = 25-30 ml/kg/day ● Sodium requirement = 1 mmol/kg/day ● Potassium requirement = 1 mmol/kg/day ● Glucose requirement = 50-100 g/dayMaintenance Fluid Regimen 1000 ml 0.18% NaCl/4% glucose with 40 mmol/L K+, alternating with 1000 ml 0.18% NaCl/4% glucose with 20 mmol/L K+ *Run at 1.25 ml/kg/hour and NOT >100 ml/hour Check U&Es, creatinine daily if giving IV fluids! Notes: ● Risk of hyponatraemia with 0.18% NaCl/4% glucose ○ Do NOT use as sole maintenance therapy if Na <132 mmol/L ● Do NOT add K+ if serum K+ >5.0 mmol/LMCQsQuestion 1 You receive a phone call from the lab confirming that a patient on your ward has a potassium level of 7.1 (normal: 3.5-5.3) and an AKI with a creatinine level that has risen from 130 to 450 in 72 hours. What is the single most appropriate next step? A. 250 ml of crystalloid fluid IV B. 10 ml of 10% calcium chloride IV C. Insert a dialysis line D. Insert a urinary catheter E. Repeat U&EsQuestion 1 - Answer You receive a phone call from the lab confirming that a patient on your ward has a potassium level of 7.1 (normal: 3.5-5.3) and an AKI with a creatinine level that has risen from 130 to 450 in 72 hours. What is the single most appropriate next step? A. 250 ml of crystalloid fluid IV B. 10 ml of 10% calcium chloride IV C. Insert a dialysis line D. Insert a urinary catheter E. Repeat U&EsQuestion 2 An 88 year old man is admitted to hospital, having been found on the floor by his carer this morning. There are no signs of infection. He is being treated with IV fluids. Urea 17 mmol/L (normal: 2.5-7.8) Creatinine 368 µmol/L (normal: 59-104) Which single further test would support the most likely diagnosis? A. Calcium B. ESR C. INR D. Creatine kinase E. TroponinQuestion 2 - Answer An 88 year old man is admitted to hospital, having been found on the floor by his carer this morning. There are no signs of infection. He is being treated with IV fluids. Urea 17 mmol/L (normal: 2.5-7.8) Creatinine 368 µmol/L (normal: 59-104) Which single further test would support the most likely diagnosis? A. Calcium B. ESR C. INR D. Creatine kinase E. TroponinQuestion 3 An 82 year old man has been confused and coughing for the past week. He is admitted to hospital and started on IV antibiotics as his renal function is markedly worse than usual. Urea 22 mmol/L (normal: 2.5-7.8) Creatinine 210 µmol/L (normal: 59-104) Which of the following drug from his regular medications would be most appropriate to withhold? A. Aspirin B. Calcium 600 mg/ colecalciferol 10µg C. Levothyroxine D. Ramipril E. TamsulosinQuestion 3 - Answer An 82 year old man has been confused and coughing for the past week. He is admitted to hospital and started on IV antibiotics as his renal function is markedly worse than usual. Urea 22 mmol/L (normal: 2.5-7.8) Creatinine 210 µmol/L (normal: 59-104) Which of the following drug from his regular medications would be most appropriate to withhold? A. Aspirin B. Calcium 600 mg/ colecalciferol 10µg C. Levothyroxine D. Ramipril E. TamsulosinQuestion 4 A 69 year old woman has repeat blood tests arranged by her general practitioner after commencing ramipril for the treatment of hypertension. She weighs 70kg. Blood tests prior to starting ramipril: Blood tests 2 weeks after starting ramipril: Urinalysis How should this patient’s renal function be classified?Question 4 - Answer A 69 year old woman has repeat blood tests arranged by her general practitioner after commencing ramipril for the treatment of hypertension. She weighs 70kg. Blood tests prior to starting ramipril: Blood tests 2 weeks after starting ramipril: Urinalysis How should this patient’s renal function be classified? A: No kidney disease presentCKD Classification 1. GFR Stage eGFR (ml/min/1.73m ) Notes 1 >90 Normal GFR. CKD only if other evidence of kidney damage: abnormal urinalysis/ histological changes on biopsy 2 60-89 Mild CKD. CKD only if other evidence of kidney damage: abnormal urinalysis/ histological changes on biopsy 3 30-59 Moderate CKD 4 15-29 Severe CKD 5 <15 End-stage renal damageQuestion 5 A 77 year old woman on your ward has chronic kidney disease. Blood results are below. Phosphate: 1.8 mmol/L (normal: 0.8-1.4) PTH: 85 pg/ml (normal: 14-65) Which of the following would be the most appropriate therapy for this patient? A. Sando-K B. Calcium carbonate C. Phosphate sandoz D. Thiamine E. AlfacalcidolQuestion 5 - Answer A 77 year old woman on your ward has chronic kidney disease. Blood results are below. Phosphate: 1.8 mmol/L (normal: 0.8-1.4) PTH: 85 pg/ml (normal: 14-65) Which of the following would be the most appropriate therapy for this patient? A. Sando-K B. Calcium carbonate C. Phosphate sandoz D. Thiamine E. AlfacalcidolQuestion 6 A 23 year old female patient is admitted onto the general surgical ward is being fasted overnight for 12 hours prior to an elective procedure. She has no significant past medical history and takes no regular medication. You have been asked by the nurse-in-charge to prescribe maintenance fluids for her during this fasting period and are told that the patient weighs 60kg. What is the correct fluid prescription over 12 hours for this patient? A. 1 litre 0.9% NaCl with 30 mmol potassium B. 1 litre 0.9% NaCl with 60 mmol potassium C. 2 litres 0.9% NaCl with 120 mmol potassium D. 2 litres 0.9% NaCl with 30 mmol potassium E. 2 litres 0.9% NaCl with 60 mmol potassiumQuestion 6 - Answer A 23 year old female patient is admitted onto the general surgical ward is being fasted overnight for 12 hours prior to an elective procedure. She has no significant past medical history and takes no regular medication. You have been asked by the nurse-in-charge to prescribe maintenance fluids for her during this fasting period and are told that the patient weighs 60kg. What is the correct fluid prescription over 12 hours for this patient? A. 1 litre 0.9% NaCl with 30 mmol potassium B. 1 litre 0.9% NaCl with 60 mmol potassium C. 2 litres 0.9% NaCl with 120 mmol potassium D. 2 litres 0.9% NaCl with 30 mmol potassium E. 2 litres 0.9% NaCl with 60 mmol potassiumNormal Requirements ● Fluid requirement = 25-30 ml/kg/day ● Sodium requirement = 1 mmol/kg/day ● Potassium requirement = 1 mmol/kg/day ● Glucose requirement = 50-100 g/dayFeedback Please take a minute now before you leave to fill in a quick feedback form: AIM Facebook Page ▶Give our Facebook page a like for updates and opportunities,just search @AIMEdinburghThank you for coming! ▶If you have any more questions, feel free to email me at s1902761@ed.ac.uk, or email accessibilityinmedicine@gmail.com