Post on 17-Jan-2018
description
transcript
CHRONIC KIDNEY DISEASE
Dr. Gerrard Uy
CHRONIC KIDNEY DISEASE Encompasses a spectrum of different
pathophysiologic process associated with abnormal kidney function and progressive decline in glomerular filtration rate
CHRONIC RENAL FAILURE Process of continuing significant irreversible
reduction in nephron number Corresponds to CKD stages 3-5 Regardless of the cause: Decreased: GFR,
tubular function & tubular reabsorption capabilities. Dysfunction fluids & electrolytes, acid base disturbances, & systemic problems develops
END STAGE RENAL RISEASE (ESRD) Represents a stage of CKD where the
accumulation of toxins, fluid, and electrolytes normally excreted by the kidneys result in uremic syndrome
Corresponds to CKD stage 5
PATHOPHYSIOLOGY OF CKD 2 mechanisms:
Initiating mechanisms specific to the underlying etiology (immune complex, toxins, etc)
Progressive mechanisms involving hyperfiltration and hypertrophy of the remaining viable nephrons
RISK FACTORS hypertension, diabetes mellitus, autoimmune disease, older age, African ancestry, a family history of renal disease, a previous
episode of acute renal failure presence of proteinuria, abnormal urinary
sediment, or structural abnormalities of the urinary tract
STAGES OF CKD Normal annual decline in GFR with age from
peak GFR (120 ml/min) attained during the 3rd decade of life is ~ 1ml/min per year
Mean GFR is lower in women than in men Measurement in albuminuria is helpful in
monitoring nephron injury > 17 mg of albumin per gram of creatinine in
males and > 25 mg of albumin per gram of creatinine in females signifies chronic renal damage
STAGES OF CKD Stage 1 and stage 2 CKD are usually
asymptomatic Stages 3 and 4 will show prominent clinical
and laboratory complications of CKD Stage 5, toxins accumulate and patients
experience a marked disturbance in their activities
ETIOLOGY Diabetic nephropathy – the most frequent
cause of CKD Hypertensive nephropathy – common cause
of CKD in the elderly
CLINICAL AND LABORATORY MANIFESTATIONS OF CKD AND UREMIA Fluid, Electrolyte and Acid Base Disorders Cardiovascular abnormalities Hematologic abnormalities Abnormal Hemostasis Neuromuscular abnormalites Gastrointestinal and Nutritional abnormalities Endocrine abnormalities Dermatologic abnormalities
FLUID, ELECTROLYTE, AND ACID BASE DISORDERS Sodium and Water Homeostasis
Total body content of sodium and water is modestly increased
Potassium Homeostasis Potassium secretion diminishes as the GFR
declines Metabolic Acidosis Disorders of Ca and Phosphate metabolism
Declining GFR leads to reduced excretion of phosphate
Decreased levels of ionized calcium 2 to decreased calcitriol production
CARDIOVASCULAR ABNORMALITIES Leading cause of morbidity and mortality in
patients at every stage of CKD Presence of any stage of CKD is a major risk
factor for ischemic cardiovascular disease Inflammatory state associated with CKD
accelerates vascular occlusive disease LVH and microvascular disease augment
myocardial ischemia Diminished availability of nitric oxide Hemodialysis with episodes of hypotension
and hypovolemia may further aggravate coronary ischemia
CARDIOVASCULAR ABNORMALITIES Increased permeability of alveolar capillary
membranes as a manifestation of the uremic state
Hypertension – most common complication of CKD
LVH and dilated cardiomyopathy are among the strongest risk factors for cardiovascular morbidity and mortality
HEMATOLOGIC ABNORMALITIES Normocytic, normochromic anemia is
observed as early as stage 3 CKD Universal by stage 4 Primary cause is insufficient production of
EPO Other causes: iron deficiency and chronic
inflammation
ABNORMAL HEMOSTASIS Prolonged bleeding time Decreased activity of platelet factor III Abnormal platelet aggregation Impaired prothrombin consumption Clinical manifestations:
Increased tendency of bleeding Prolonged bleeding from surgical procedures Menorrhagia Spontaneous GI bleeding Greater susceptibility to thromboembolism
NEUROMUSCULAR ABNORMALITIES CNS, peripheral, and autonomic neuropathy Due to retained nitrogenous metabolites and
middle molecules including PTH Clinical manifestations of uremic
neuromuscular disease usually become evident at stage 3 CKD
Symptoms: Disturbances in memory and concentration Sleep disturbance Hiccups, cramps and fasciculations
NEUROMUSCULAR ABNORMALITIES Peripheral neuropahty becomes evident at
stage 4 CKD Sensory nerves are involved more than motor Lower extremity > upper extremity “restless leg syndrome” Evidence of peripheral neuropathy without
another cause (e.g DM) is a firm indication for starting renal replacement therapy
GASTROINTESTINAL ABNORMALITIES Uremic fetor – urine like odor on the breath Gastritis and peptic ulcer disease Prone to constipation Retention of uremic toxins also lead to
anorexia, nausea, and vomiting Protein – energy malnutrition common in
advanced CKD and is an indication for starting renal replacement therapy
Assessment of PEM should begin in stage 3 CKD
ENDOCRINE METABOLIC DISTURBANCES Impaired glucose metabolism Increased postprandial glucose, normal
fasting glucose In women with CKD, estrogen levels are low Presence of menstrual abnormalities and
infertility GFR < 40 ml/min, associated with
spontaneous abortions In men, testosterone levels are low leading to
sexual dysfunction and oligospermia
DERMATOLOGIC ABNORMALITIES Pruritus is common Hyperpigmentation – due to deposition of
retained pigment molecules, urochromes First line of management is to rule out
scabies and control phosphate concentrations
APPROACH TO PATIENT Identify if it is ACUTE RENAL FAILURE or
CHRONIC. Identify co-morbidities such as hypertension,
diabetes mellitus, cardiovascular disease, etc Evaluate uremic syndrome Findings that suggest chronic kidney disease
include anemia, evidence of renal osteodystrophy (radiologic or laboratory), and small scarred kidneys
APPROACH TO PATIENT Most useful imaging study is renal ultrasound
– presence of bilaterally small kidney (<8.5 cm) supports diagnosis of CKD
Hypophosphatemia, hypocalcemia, and elevated PTH and ALP suggests chronicity
Normochromic, normocytic anemia
MANAGEMENT Slowing the progression of CKD
ECFV depletion, uncontrolled hypertension, urinary tract infection, obstructive uropathy, exposure to nephrotoxic agents
Protein restriction – slow the rate of renal decline at earlier stages of renal disease Daily protein intake of 0.6 – 0.75 gm/kg/day At least 50% = high biologic value protein Sufficient energy intake, 35 kcal/kg
Reducing intraglomerular hypertension and proteinuria Control of systemic and glomerular hypertension
MANAGEMENT Slowing the progression of diabetic renal
disease Prognosis of diabetic patients on dialysis is poor
with survival comparable to many forms of cancer
Recommended preprandial glucose <90-130 mg/dl
Hba1c <7% Testing for microalbumin is recommended in all
diabetic patients at least annually
MANAGEMENTDecrease fluid 1000ml/dayDecrease protein (.5-1kg body weight)Decrease sodium (1-4gm variable)Decrease potassiumDecrease phosphorous (<1000mg/day)Dialysis (peritoneal, hemodialysis)RBC, Vitamin D (calcitrol replacement) etc
DIALYSISDr. Gerrard Uy
DIALYSIS Leading cause of ESRD:
Diabetes mellitus hypertension
Other causes of ESRD: Glomerulonephritis Polycystic kidney disease Obstructive uropathy
2 types of dialysis Hemodialysis Peritoneal Dialysis
CRITERIA FOR INITIATING DIALYSIS Presence of uremic symptoms Hyperkalemia unresponsive to conservative
measures Persistent extracellular volume expansion
despite diuretic therapy Acidosis unresponsive to medical therapy Bleeding diasthesis Creatinine clearance or estimated GFR
<10ml/min
GENERAL PRINCIPLE Movement of fluid and molecules across a
semi permeable membrane from one compartment to another
Hemodialysis – Move substances from blood through a semi permeable membrane and into a dialysis solution (dialysate –bath) (synethetic membrane)
Peritoneal – Peritoneal membrane is the semi permeable membrane
GOALS OF DIALYSIS To remove both low and high molecular
weight solutes Majority of patients with ESRD require 9-12
hrs of dialysis each week, usually divided into 3 equal sessions
COMPLICATIONS DURING HEMODIALYSIS Hypotension – most common acute
complication Muscle cramps Anaphylactoid reactions
Type A reactions – IgE mediated hypersensitivity reaction
Type B reaction – nonspecific chest and back pain
COMPLICATIONS OF PERITONEAL DIALYSIS Peritonitis
Elevated peritoneal fluid leukocyte Typical presentation: pain and cloudy dialysate Most common etiology: gram positive cocci
Catheter associated nonperitonitis infections Weight gain Residual uremia hyperglycemia
DISEQUALIBRIUM SYNDROME
Fluid removal and decrease in BUN during hemodilaysis which cause changes in blood osmolarity.These changes trigger a fluid shift from the vascular compartment into the cells. In the brain, this can cause cerebral edema, resulting in increase intracranial pressure and visible signs of decreasing level of consciousness. Symptoms: Sudden onset of headache, nausea and vomiting, nervousness, muscle twitching, palpitation, disorientation and seizures
Treatment: Hypertonic saline, Normal saline
HEMO ADVANTAGES & DISADVANTAGES
Rapid fluid removalRapid removal of urea
& creatinineEffective K+ removalLess protein lossLower triglyceridesHome dialysis possibleTemporary access at
the bedside
Vascular access problems
Dietary & fluid restrictions
HeparinizationExtensive equipmentHypotensionAdded blood lostTrained specialist
Advantages Disadvantages
PD ADVANTAGES AND DISADVANTAGES
Immediate initiationLess complicatedPortable (CAPD)Fewer dietary
restrictionsShort training timeLess cardio stressChoice for diabetics
Bacterial/chemical periotonitis
Protein lossExit site of catheterSelf imageHyperglycemiaSurgical placement of
catheterMultiple abdominal
surgery
Advantages Disadvantages
TRANSPLANTATION Treatment of choice for advanced chronic
renal failure Mortality rates after transplantation are
highest in the first year and are age related 2% for 18-34 yrs 3% for 35-49 yrs 6.8% for > 50 yrs
COMMON PROBLEMS IN TRANSPLANTATION Infections Tissue Rejection Malignancy (skin and lip carcinoma,
lymphomas, cervical carcinoma) Hypercalcemia Hypertension Chronic hepatitis anemia