Acute Renal Failure PDF

Acute renal failure Salwa Ibrahim MD Agenda Definition Aetiology Clinical presentation Investigations treatment definition Abrupt decline in renal functions overs or days Associated with rise in serum creatinine and blood urea aetiology Pre renal : hypovolemia, shock,...

Acute renal failure Salwa Ibrahim MD Agenda Definition Aetiology Clinical presentation Investigations treatment definition Abrupt decline in renal functions overs or days Associated with rise in serum creatinine and blood urea aetiology Pre renal : hypovolemia, shock, congestive heart failure Renal: acute tubular necrosis, acute cortical necrosis, acute glomerulonephritis, acute intersitial nephritis Post renal : prostatic hypertrophy, stone Pre-renal causes of ARF Haemorrhage Shock Congestive heart failure Renal causes Acute tubular necrosis Either ischemic or toxic or secondary to sepsis (diabetic foot, blood sepsis) Ischemic with prolonged hypoperfusion Toxic like garamycin, radiocontrast Pigments like myoglobin, hemoglobin , uric acid crystals, bilirubin Acute cortical necrosis Postpartum hemorrhage with cortical infaction If massive it causes irreversible ARF Acute post strept GN Sore throat with passage of coca cola urine Haematuria with red cell casts Positive ASOT Resolves within weeks  Usually associated with oligouria or anuria Post renal Bilateral ureteric stones ARF Bladder neck obstruction (BPH OR PROSTATE CANCER)  Change in urine volume (oliguria, anuria, polyuria Clinical with recovery) presentatio Symptoms of complications n (fluid overload, metabolic acidosis, uremic encephalopathy, bleeding tendency, muscle weakness) How to approach ARF case History taking : blood loss, diarrhoea, sepsis, exposure to drugs like aminoglycosides radiocontrast, symptoms suggestive of obstructive uropathy like passage of stones, Bladder neck obstruction symptoms, muscle injury, liver cirrhosis, hemolysis, gout Examination Assess Examine Check Assess for Examine for Check for hypovolemia : BP, supra pubic mass systemic disease PULSE RATE, (bladder) (rash, vasculitis SKIN TUGER, lesions) URINE VOLUME, IF NECCEAERY CVP MONITORING Investigations Kidney function tests ( blood urea, serum creatinine( Urine analysis (haematuria, RBCs casts) Electrolytes (sodium, potassium) Arterial blood gases( metabolic acidosis) CBC : Anaemia , leucocytosis in sepsis Ultrasound kidneys and bladder To differentiate ARF from CKD To rule out obstruction Management First rule out obstruction (examination of suprapubic dullness, US, insertion of urinary catheter) Check volume status ( BP, Pulse, CVP) Rule out sepsis (fever High CRP leucocytosis) D/C nephrotoxic agents (aminoglycosides, ACEI, ARBs, NSAIDs)  Hydrate if dehydrated Transfuse blood with haemorrhage Manageme Inotropes in cardiogenic shock nt Antibiotics in sepsis Adjust drug doses Treat the underlying aetiology Antibiotics in post strept GN, BP control, diuretics if overloaded Aggressive hydration in myoglobinuria with urinary alkalinization Relieve obstruction in obstructive uropathy Stop any offending drugs Treatment of complications Treatment of volume overload Salt and water restriction Diuretics like frusemide 125-250 mg daily Hemodialysis with pulmonary edema  Sodium bicarb IV 50 mEq every 8 Treatment hours if pH less of than 7.2 metabolic acidosis Haemodialysis If intractable metabolic acidosis (pH