Post Contents List
- 1 Acute Renal Failure (ARF)
- 2 ARF (Acute renal failure) is characterized by :
- 3 ARF may be of 3 types:
- 4 PRERENAL ARF
- 5 Hepatorenal syndrome
- 6 INTRINSIC RENAL ARF
- 7 Common causes of intrinsic ARF
- 8 Acute tubular necrosis
- 9 POST RENAL ARF
- 10 MAJOR CAUSES OF ARF PRERENAL
- 11 Renal Causes of ARF
- 12 Pathophysiology
- 13 FEATURES TO DIFFERENTIATE ACUTE AND CHRONICChronic Hepatitis Classification viral hepatitis Clinical features and Treatment. Read more ... » RENAL FAILURE ARF
- 14 Clinical features of ARF
- 15 Interstitial nephritis suggested by
- 16 Urinary obstruction suggested by –
- 17 Prostate enlargement suggested by
- 18 Acute tubular necrosis (ATN) i.e. Ischemic ARF, Nephrotoxic ARF
- 19 BLOOD
- 20 ULTRASOUND
- 21 PYELOGRAPHY –
- 22 COMPLICATIONS
- 23 Causes of Hypocalcemia in ARF
- 24 TREATMENT OF ARF
Acute Renal Failure (ARF)
AcuteCOMMUNITY ACQUIRED PNEUMONIA Signs and Symptoms with Treatment. Read more ... » renalDiabetic Nephropathy and Renal complications of DM (Diabetes Mellitus). Read more ... » failure due to intratubular crystal precipitation can be seen in a variety of clinicalCOMMUNITY ACQUIRED PNEUMONIA Signs and Symptoms with Treatment. Read more ... » settings, the most common being acute uric acid nephropathyDiabetic Nephropathy and Renal complications of DM (Diabetes Mellitus). Read more ... »
Acute renal failure (ARF) is defined as a sudden decrease of normal kidneyDiabetic Nephropathy and Renal complications of DM (Diabetes Mellitus). Read more ... » function that compromises the normal renal regulation of fluid, electrolyte, and acid–base homeostasis.
ARF (Acute renal failure) is characterized by :
- · Decrease in GFR (reversible).
- · Retention of nitrogenous wastes.
- · Disturbance of balance of fluid volume, electrolytes and acid-base.
- Oliguria: Urine output <0.5 mL/kg/h in infants or <500 mL/1.73 m2/d in older children
- Anuria: Total cessation of urinary output
- Polyuria: Urine output >2 L/m2/d in infants and children or 3 L/d in adults
- ·Oliguria – i.e. urine output <400 ml/day.
- Pre-renal and post-renal failure may be reversible by prompt and appropriate treatment.
- ARF is usually asymptomatic. It is diagnosed by a recent increase in blood urea and creatinine.
ARF may be of 3 types:
- 1. Prerenal
- 2. Renal
- 3. Post renal.
- Pre-renal –
- There is renal hypoperfusion. Renal parenchyma is normal.
- Renal –
- Renal parenchymal diseaseCOMMUNITY ACQUIRED PNEUMONIA Signs and Symptoms with Treatment. Read more ... » is present.
- Post renal –
- There is urinary tract obstruction leading to renal failure.
- ARF is mostly reversible.
- It is reversible by proper perfusion of kidneys so that glomerular ultrafiltration pressure becomes normal. Renal parenchymal tissue is normal.
- If tissue hypoperfusion persists there is damage of renal parenchyma.
- Due to hypoperfusion there is :
- Activation of sympathetic nervous systemCOMMUNITY ACQUIRED PNEUMONIA Signs and Symptoms with Treatment. Read more ... ».
- Activation of renin angiotensin – aldosteroneAldosteronism Clinical features Causes and Treatment. Read more ... » system .
- Release of AVP / ADH (arginine vasopressinVasopressin. Read more ... » / antidiuretic hormone).
- Norepinephrine, angiotensin II and AVP cause vasoconstriction in non-essential areas, inhibit salt loss through sweat glands, stimulate thirst, promote salt and water retention.
- Prostaglandin E2and prostacyclin cause dilatation of afferent arterioles.
- Angiotensin II causes preferential constriction of efferent arterioles.
- Thus glomerular filtration pressure is increased and glomerular filtration rate is increased.
- All these processes help to counter the renal hypoperfusion.
- GFR (Glomerular filtration rate) is maintained only if systemic pressure is above 80 mmHg.
- In advanced cirrhosis and other liver diseases there is severe form of ARF, called hepatorenal syndrome.
- Mortality is very high.
INTRINSIC RENAL ARF
- This may be due to :
- 1. Disease of larger renal vessels
- 2. Disease of glomeruli
- 3. Ischemic and nephrotoxic ARF
- 4. Tubulointerstitial disease.
Common causes of intrinsic ARF
- · Ischemia (Acute tubular necrosis)
- · Nephrotoxins.
Acute tubular necrosis
- Acute tubular necrosis or Ischemic ARF occurs in trauma, haemorrhage, sepsisSepsis (Septic Shock) Definition Diagnosis and Pathophysiology. Read more ... », volume depletion. It can occur on preexisting renal disease.
POST RENAL ARF
- Post renal ARF is usually due to obstructive causes and are fully reversible with surgical treatment .
MAJOR CAUSES OF ARF PRERENAL
- Vomiting and diarrhea
- Diabetes mellitusHyperglycemic Hyperosmolar State (HHS) Acute Complication Of DM. Read more ... » (osmotic diuresis)
- Pancreatitis Peritonitis
- Low cardiacMANAGEMENT of Acute Myocardial Infarction (AMI) -1. Read more ... » output Pulmonary hypertensionAldosteronism Clinical features Causes and Treatment. Read more ... » Sepsis
- Anti hypertensives
- Norepinephrine Epinephrine
- Cirrhosis and ascites (Hepatorenal)
- ACE inhibitorsHeart Failure Treatment Heart Failure GENERAL PRINCIPLES. Read more ... »
- Multiple meyloma.
Renal Causes of ARF
- Renal artery obstruction by thrombus, embolism Renal vein thrombosis
- Thrombotic thrombocytopeniac purpura Toxaemia of pregnancy
- DIC (Disseminated intravascular coagulation) SLE (Systemic lupus erythematosus) Scleroderma
- Acute tubular necrosis (Ischemia or hypoperfusi6n)
- PPH (Post Partum Haemorrhage) Abruptio placentae
- Drugs Cyclosporin
- Radiocontrast dye
- Interstitial nephritis Infections.
- Calculi Cancer
- Stricture Bladder neck obstruction
- Urethral obstruction.
- ARF is commonly precipitated by an ischemic or nephrotoxic event.
- Initial vasodilatation is followed by intense vasoconstriction, with blood redistributed from the cortex to the juxtamedullary nephrons
- Intratubular debris and cast formation develop.
- Tubular fluid leaks backward across the injured tubular membrane, which, in addition to tubular obstruction, causes further hemodynamic changes.
- Recent increase in urea and creatinine.
- There is history suggestive of the cause of ARF like diarrhoea, vomiting, burns etc.
- Anaemia Neuropathy
- Rena I osteodystrophy Small, scarred kidneys
- Kidney size may be increased or normal in CRF due to :
- Diabetic nephropathy AmyloidosisAmyloidosis Symptoms Diagnosis Prognosis and Treatment. Read more ... »
- Polycystic kidney diseaseTubular Diseases of the Kidney Types Clinical Features Diagnosis with Treatment. Read more ... »
- Usually the kidney size is reduced in CRF .
Clinical features of ARF
- Orthostatic hypotensionHyperglycemic Hyperosmolar State (HHS) Acute Complication Of DM. Read more ... »
- Systemic hypotension (BP <90 mmHg) –v TachycardiaHyperglycemic Hyperosmolar State (HHS) Acute Complication Of DM. Read more ... » (Pulse rate >100 Imin)
- Raised JVP
- Dry skin and mucous membrane
- Reduced sweating
- History of NSAIDs, ACE-I (ACE inhibitors), ARBs
- (Angiotensin receptor blockersHeart Failure Treatment Heart Failure GENERAL PRINCIPLES. Read more ... ») v Decreased urine output
- Decreased body weig ht
- Hlo Radiocontrast dye
- Flank painChronic pancreatitis Causes Symptoms Diagnosis and Treatment. Read more ... »
- Atheroembolization suggested by Sic nodules, ischemia of fingers, toes
- Glomerulonephritis suggested by oliguria, edema, hypertension, active urine sediment.
Interstitial nephritis suggested by
- pruritic (that itch) red rash.
Urinary obstruction suggested by –
- Colicky pain
- Suprapubic and flank pain
- oFlank pain – loin tropain.
Prostate enlargement suggested by
- Oliguria or Anuria.
- · Urine is acellular
- · Inactive sediments or hyaline casts present.
Post renal ARF
- · Inactive sediment
- · HematuriaDIAGNOSIS and Investigations OF SECONDARY HYPERTENSION. Read more ... »
- · Pyuria.
Acute tubular necrosis (ATN) i.e. Ischemic ARF, Nephrotoxic ARF
- · Pigmented, muddy brown granular casts with tubule epithelial cells in urine.
- · Mild proteinuria « 19/day
- Tubulointerstitial disease – RBC casts in urine.
- · WBC casts in urine.
- · Nonpigmented granular casts in urine.
Chronic renal disease
- Broad granufar casts in urine.
- Eosinophils -in urine – allergic interstitial nephritis. Uric a~id crystal~ in – acute urate nephropathy.
Proteinuria >1g/day suggests gIomerular disease.
Heavy proteinuria> 1 g/day also seen in patients on NSAIDs, ampicillin, rifampicin, interferon alpha.
Bilirubin in urine in hepatorenal syndrome.
Fractional excretion of sodium
- FE Na < 1 % in prerenal ARF
- FE Na > 1 % in ischemic, nephrotoxic (tubular disease).
- Serum creatinine: increases progressively in renal failure and is a very good indicator of renal failure.
- Ultrasonography is useful for post renal ARF to diagnose causes like – urinary tract obstruction, pelvicalyceal dilatation, retroperitoneal fibrosis, neoplasia.
PLAIN X-RAY ABDOMEN
- For nephrolithiasis.
retrograde, antegrade –
- for localization of site of obstruction.
- For patency of renal arteries and veins.
- Non-invasive renal vascular study. CONTRAST ANGIOGRAPHY
RENAL BIOPSY –
- For definitive diagnosisCOMMUNITY ACQUIRED PNEUMONIA Signs and Symptoms with Treatment. Read more ... ».
- For intrinsic renal ARF e.g. glomerulonephritis, vasculitis, thrombocytopenic purpura, interstitial nephritis.
- There is impairment of renal excretion of sodiurtl, potassium and water.
- · Volume overload
- · Raised JVP
- · Hyponatrem ia
- · Hyperkalemia
- · Hyperphosphatemia
- · Hypocakemia
- · Hypermagnesemia
- · Metabolic acidosis
- · Uremia
- · Weight gain
- · Basal lung rales
- · Dependent edema
- · Pulmonary edemaPulmonary Edema Causes Diagnosis with Treatment. Read more ... »
- · Cerebral edema
- · Seizures
- · Arrhythmias
- · Metabolic acidosis
- · Lactic acidosis
- · Hemolysis
- · Leucocytosis
- · GI bleeding and bleeding from other sites
- · Infections
- Pericarditis Pericat”dial effusion Pulmonary embolism Uremic syndrome.
Causes of Hypocalcemia in ARF
- Metastatic deposition of calcium phosphate when the serum calcium X phosphate in mgjdl is > 70.
- Tissue resistance to parathyroid hormone. Decreased 1,25 dihydroxyvitamin D.
Effects of hypocalcemia
- Muscle cramps Seizures Hallucinations Confusion
- Prolonged QT.
TREATMENT OF ARF
- Prevention of pre-renal and post-renal causes Avoid drugs causing ARF
- Low drugCOMMUNITY ACQUIRED PNEUMONIA Signs and Symptoms with Treatment. Read more ... » dosage of nephrotoxic drugs Maintain fluid balance
- Maintain sodiumRenin and Hypertension Low renin and High Renin essential hypertension with Treatment. Read more ... », potassium, phosphate, calcium levels
- Invasive and noninvasive hemodynamic monitoring
- Low dose dopamineDopamine. Read more ... »
- Loop diureticsAcetazolamide. Read more ... » (frusemide, torsemide) Antihyperte~sives like CCB (Calcium channel blockers) and Alpha-blockers
- Atrial natriuretic peptide
- Antioxidants GlucocorticoidsSome Facts about Glucocorticoid & Major side effects. Read more ... » Alkylating agents Plasmapharesis
- Relief of obstruction of urinary tract
- Oral or IV sodium bicarbonateSodium Bicarbonate. Read more ... » if arterial pH <7.2 or serum bicarbonate < 15 meq/L
- Restriction of dietary phosphate
- Oral aluminum hydroxide
- Calcium carbonateCalcium Carbonate. Read more ... »
- Vitamin D
- Restriction of dietary protein 0.6 g/kg/day Carbohydrate 100 g/day
- Blood transfusion if required
- Rarely erythropoietin for anemia
- PPI (proton pump inhibitor) and H2blockers Anti biotics
- Dialysis – if hemodynamically unstable peritoneal dialysisDialysis Indications Complications and Dialysis for Renal Failure. Read more ... » is done
- HemodialysisDialysis Indications Complications and Dialysis for Renal Failure. Read more ... » – in uremic syndrome, refractory hyperkalemia, acidosis
- Continuous renal replacement therapy (CRRT) Continuous arteriovenous hemodiafiltration (CAVHD)
- Continuous venovenous hemodiafiltration (CVVHD).