Renal Failure PDF

INTRODUCTION Kidneys are vital organs for maintaining internal homeostasis Kidneys have many functions Regulating the acid-base & electrolyte balances of body by filtering the blood Selectively reabsorbing water & electrolyt...

INTRODUCTION Kidneys are vital organs for maintaining internal homeostasis Kidneys have many functions Regulating the acid-base & electrolyte balances of body by filtering the blood Selectively reabsorbing water & electrolytes Excreting urine Excreting metabolic waste products including urea, creatine, uric acid & foreign chemicals Classification Disorders of kidney can be classified into following diseases /stages Acute renal failure Chronic renal failure End stage renal failure / uremic syndrome DIAGNOSTIC PROCEDURES IN RENAL DISEASES SERUM CHEMISTRY – includes Na,Cl, K , BUN(8to18mg/dl) Creatine(o.6to1.2mg/dl) Glucose, phosphates & calcium levels For GFR serum creatine & BUN levels are imp In advancing renal dysfunction – increase in serum creatine &BUN Decrease in serum calcium URINALYSIS – Detection of blood in urine Determination of specific gravity /osmality Microscopic examination Halmark of renal dysfunction detected by urinalysis ie, Hematuria & Protinuria Hematuria is presence of blood in the urine Causes are neoplasm, proliferative glomerulonephritis & prostatic Hypertrophy Investigations are urine cytology, intravenous pyelography to rule out intrinsic abnormalities PROTEINURIA is a sensitive sign for renal dysfunction Benign conditions include exercise, fever & stress produce elevated proteins Pts who excrete >3gm of protein/day suggests nephrotic syndrome CREATINE CLEARANCE TEST INTRAVENOUS PYELOGRAPHY (IVP) RENAL ULTRASONOGRAPHY distinguish solid tumors from fluid filled cysts Useful for pts with severe renal failure who are not candidates for IVP Indicated to determine kidney size or to view any obstruction CT – detection of retroperitoneal mass MRI – does not use ionising radiation BIOPSY Percutenous needle biopsy guided by ultrasonography Performed in supine position RENAL FAILURE classified according to onset (acute/chronic) Location ( pre renal/renal/post renal ) ACUTE RENAL FAILURE characterized by rapid decline in kidney function over a period of days to weeks leading to severe azotemia ( increase in nitrogenous waste products in blood ) Clinical course of ARF progress through 3 stages OLIGURIA – urine volume 400ml/day RECOVERY ARF divided into 3 diagnostic categories PRE RENAL FAILURE- Any condition that comprimises renal function without permenant physical injury to the kidney reffered to as pre renal azotemia renal failure associated with volume depletion cardiovascular diseases decrease cardiac output changes in fluid volume due to sepsis POST RENAL FAILURE Conditions that obstruct the flow of urine at any level of the urinary tract and that subsequently decreases the GFR Obstruction results from prostatic enlargement (benignhypertrophy/malignant neoplasm ) or cervical cancer Seen in older men as a result of enlargement of prostate Renal ultrasonography shows a dilated collecting system (hydronephrosis ) ACUTE INTRINSIC RENAL FAILURE Pathogenesis appear to be related to immune complex & complement mediated damage to the kidney Etiology are glomerular disease ,vascular disease & tubulo interstitial diseases Other causes are infiltrative diseases like lymphoma or sarcoidosis Infections like syphilis or toxoplasmosis Medications cause hypersensitivity reactions & eosinophils in the urine Chronic Renal Failure involve diffuse bilateral destruction of the renal parenchyma. caused by many diseases that devastate the nephron mass. Etiology of End-Stage Renal Disease Diabetes mellitus Hypertension Glomerulonephritis Interstitial nephritis, pyelonephritis and polycystic kidney disease CLINICAL PROGRESSION The clinical course of CRF is divided into three progressive stages: (1)Diminished renal reserve, (2) Renal insufficiencey (3) End-stage renal failure or uremia. Diminished renal reserve is characterized by normal serum creatinine and BUN levels. The second clinical stage, renal insufficiency, occurs when the GFR drops to 25% of normal As nephron destruction progresses, the GFR falls, and the BUN level rises The third and final stage of chronic renal failure is end-stage renal failure or uremia. With continued destruction of nephrons (destruction of > 90% of nephron mass), frank renal disease follows, with associated polyuria. The complex biochemical changes, include anemia, hypocalcemia, hyperphosphatemia, and metabolic acidosis. Oral and Radiographic Manifestations of Renal Disease Oral manifestations Enlarged (asymptomatic) salivary glands Decreased salivary flow & Dry mouth Odor of urea on breath & Metallic taste Increased calculus formation & Low caries rate Enamel hypoplasia & Dark brown stains on crowns Extrinsic (secondary to liquid ferrous sulfate therapy) Intrinsic (secondary to tetracycline staining) Dental malocclusions Pale mucosa with diminished color demarcation Low-grade gingival inflammation Petechiae and ecchymosis Bleeding from gingiva & Prolonged bleeding Candidal infections Burning and tenderness of mucosa with Erosive glossitis Tooth erosion (secondary to regurgitation associated with dialysis) Dehiscence of wounds Radiographic manifestations Demineralization of bone Loss of bony trabeculation Ground-glass appearance Loss of lamina dura Giant cell lesions, “brown tumors” Socket sclerosis Pulpal narrowing and calcification Tooth mobility Arterial and oral calcifications MEDICAL MANAGEMENT OF CHRONIC RENAL FAILURE Conservative Therapy managing diet, fluid, electrolytes, and calcium- phosphate balance and also the prevention and treatment of complications.Dietary regulation of protein(20 to 40 g per day) may improve acidosis, azotemia. The restriction of protein not only reduces BUN levels but reduces potassium and phosphate intake and hydrogen ion production. low-protein intake reduces the excretory load of the kidney, thereby reducing glomerular hyperfiltration, intraglomerular pressure, and secondary injury of nephrons This restricted diet is often supplemented with multivitamins Recently, BEANS, has gained popularity. B - Blood pressure should be maintained in a target range lower than 130/85 mm Hg. E - Hemoglobin levels should be maintained at 10 to 12 g/dL with Erythropoietin. A - Access for dialysis should be created when the serum creatinine reaches > 4.0 mg/dL or the GFR falls to < 20 mL/min. N - Nutritional status is important to avoid protein malnutrition, S - Specialty evaluation by a nephrologist should be instituted when serum creatinine is > 3.0 mg/dL.  Dental Considerations and Management of the Patient with Renal Disease Before treatment Determine dialysis schedule and treat one day after dialysis. Consult with patient’s nephrologist for recent laboratory tests and discussion of antibiotic prophylaxis. Identify arm and avoid taking blood pressure measurement/injection/ medication on this arm. Evaluate patient for hypertension/hypotension. Institute preoperative hemostatic aids when appropriate. Determine underlying cause of renal failure (underlying disease may affect provision of care). Obtain routine annual dental radiographs to establish presence and follow manifestations of renal osteodystrophy. Consider routine serology for HBV, HCV, and HIV antibody. Consider antibiotic prophylaxis when appropriate. Consider sedative premedication for patients with hypertension. During treatment Perform a thorough history and physical examination for presence of oral manifestations. Aggressively eliminate potential sources of infection/bacteremia. Use adjunctive hemostatic aids during oral/periodontal surgical procedures. Maintain patient in a comfortable un cramped position in the dental chair. Allow patient to walk or stand intermittently during long procedures. After treatment Use post surgical hemostatic agents. Encourage meticulous home care. Institute therapy for xerostomia when appropriate. Consider use of postoperative antibiotics for traumatic procedures. Avoid use of respiratory-depressant drugs in presence of severe anemia. Adjust dosages of postoperative medications according to extent of renal failure. Ensure routine recall maintenance.