8Classifications Acute versus chronic Pre-renal, renal, post-renal Anuric, oliguric, polyuric
9Acute Versus Chronic Acute Chronic sudden onsetrapid reduction in urine outputUsually reversibleTubular cell death and regenerationChronicProgressiveNot reversibleNephron loss75% of function can be lost before its noticeable
10Acute Renal Failure Definition Renal function is diminished to the point where body fluid hemostasis can no longer be maintained.
13Prerenal Causes The most common cause of acute renal failure. HypovolemiaHemorrhageGastroenteritisHypoproteinemiaBurnsRenal or adrenal disease with salt wastingHypotensionSepticemiaDICHypothermiaCongestive heart failureHypoxiaRDS and pneumoniaAortic calmping
14Prerenal Azotemia In severe cases hypovolemic shock. Oliguria is present in most individuals.Normal or increased urine output indicates eitherAminogycoside or ATNnephrotoxicity
15Prerenal ARF of Newborns and Infants CausesPeri-natal hemorrhage - Twin-twin transfusion, complications of amniocentesis, birth traumaNeonatal hemorrhage - Severe intra-ventricular hemorrhage, adrenal hemorrhage.Perinatal asphyxia and hyaline membrane disease.Other causes as NIC &renal vein thrombosis
16Prerenal ARF of Children The most common cause of ARFPrerenal ARF:The most common cause of hypovolemia in children is gastroenteritis.Congenital and acquired heart diseases are important causes of ARF in this age group.
18Intrinsic Renal Failure Glomerular diseases: The most common causes in older childrenNephritic syndrome of hematuria and edema is synonymous with a glomerular etiology of ARF.
19Intrinsic Renal Failure *Localized intravascular coagulationAcute dehydration HUSThe most common causes of ARF in toddlers
20Acute Tubular Necrosis Tubular diseases:Acute tubular necrosis(Absence of arterial or glomerular lesions).There are major histologic changes that take place in ATN:(1) tubular necrosis with sloughing of the epithelial cells(2) occlusion of the tubular lumina by casts and by cellular debris(3)Back leak of filtrate
21Major Causes of Acute Tubular Necrosis Renal Ischemia:* Severe pre-renal disease from any cause.Exposure to Nephrotoxins:* Amphotericin BAminoglycosides * Heme Pigments * NSAID's (hemoglobinuria/myoglobinura)Require a period of dialysis before spontaneous resolution occurs.
23Intrinsic ARF of Children Hemolytic uremic syndrome (HUS) is the most common cause of ARF in children.The disease is associated with a diarrheal prodrome caused by Escherichia coliChildren usually present with microangiopathic anemia, thrombocytopenia, colitis, mental status changes, and renal failure.
26Diagnostic Evaluation: Urinalysis shows proteinuria, hematuria, casts.Serum creatinine and BUN levels are elevated; arterial blood gas levels, serum electrolytes may be abnormal.Renal untrasonography rules out treatable obstructive uropathy.
27Laboratory Findings in the Differential Diagnosis of Acute Renal Failure:
29Therapeutic and Pharmacologic Interventions: Surgical relief of obstruction .Correction and control of biochemical imbalances.Restoration and maintenance of blood pressureLow protein diet with supplemental amino acids and vitamins.Initiation of dialysis, or continuous renal replacement therapy for patients with progressive azotemia .
30Continuous Hemofiltration (HF) It is useful in patients with ARF.Continuous AVHF Continuous VV HFBlood is pumped By a pumpthrough fillterby patient heart
31ARF: Life Threatening Conditions HyperkalemiaVolume overloadVascular access
39Problems Related to ESRD Metabolic – K/CaVolume overloadAnemia, platelet disorder, GI bleedPericarditisPeripheral neuropathy, dialysis dementiaAbnormal immune function
40Dialysis ½ of patients with CRF eventually require dialysis Diffuse harmful waste out of bodyControl BPKeep safe level of chemicals in body2 typesHemodialysisPeritoneal dialysis
41Hemodialysis 3-4 times a week Takes 2-4 hours Machine filters blood andreturns it tobody
42Types of Access Temporary site AV fistula AV graft Surgeon constructs by combining an artery and a vein3 to 6 months to matureAV graftMan-made tube inserted by a surgeon to connect artery and vein2 to 6 weeks to mature
45What This Means For You No BP on same arm as fistula Protect arm from injuryControl obvious hemorrhageBleeding will be arterialMaintain direct pressureNo IV on same arm as fistulaA thrill will be felt – this is normal
46Access Problems AV graft thrombosis AV fistula or graft bleeding AV graft infectionSteal PhenomenonEarly post-opIschemic distallyApply small amount of pressure to reverse symptoms
48Dialysis Related Problems Lightheaded –give fluidsHypotensionDysrhythmiasDisequilibration SyndromeAt end of early sessionsConfusion, tremor, seizureDue to decrease concentration of blood versus brain leading to cerebral edema