Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Nephrology PPT 2 Chronic Kidney Disease Lecture Notes
CHRONIC KIDNEY DISEASE
Staging
? Chronic kidney disease (CKD) encompasses a spectrum of different
pathophysiologic processes associated with abnormal kidney function and a
progressive decline in glomerular filtration rate (GFR), present for >3 months.
? PATHOPHYSIOLOGY OF CHRONIC KIDNEY DISEASE ?
? initiating mechanisms specific to the underlying etiology
? a set of progressive mechanisms, involving hyperfiltration and hypertrophy of
the remaining viable nephrons, that are a common consequence following
long-term reduction of renal mass, irrespective of underlying etiology
? Eventually, these short-term adaptations of hypertrophy and
hyperfiltration become maladaptive leading to sclerosis and dropout
of the remaining nephrons
RISK FACTORS
? smal for gestation birth weight
? childhood obesity
? hypertension
? diabetes mel itus
? autoimmune disease
? advanced age
? African ancestry
? a family history of kidney disease
? a previous episode of acute kidney injury
? presence of proteinuria
? abnormal urinary sediment
? structural abnormalities of the urinary tract.
? The normal annual mean decline in GFR with age from the peak GFR
(~120 mL/min per 1.73 m2) attained during the third decade of life is
~1 mL/min per year per 1.73 m2, reaching a mean value of 70 mL/min
per 1.73 m2 at age 70.
Etiology of CKD
? Diabetes
? Hypertension
? Glomerulonephritis
? Hereditary cystic and congenital renal disease
? Interstitial nephirits and pyelonephritis
Evaluation
? estimation of GFR ? only when creatinine levels are steady
? Measurement of albuminuria ?
? 24-h urine collection
? protein-to-creatinine ratio in a spot first-morning urine sample
Clinical features
? Stages 1 and 2 CKD - asymptomatic
? stages 3 and 4- clinical and laboratory complications of CKD
? most evident complications include
? anemia and associated easy fatigability;
? decreased appetite;
? abnormalities in calcium, phosphorus, and mineral-regulating hormones, such as
1,25(OH)2D3 (calcitriol), parathyroid hormone (PTH), and fibroblast growth factor 23
(FGF-23);
? and abnormalities in sodium, potassium, water, and acid-base homeostasis.
Clinical manifestations
Uremia
? Syndrome that incorporates all signs and symptoms seen in various
systems throughout the body
Uremic symptoms
Urinary system
? Polyuria
? Results from inability of kidneys to concentrate urine
? Occurs most often at night
? Specific gravity fixed around 1.010
? Oliguria
? Occurs as CKD worsens
Metabolic disturbance
? Waste product accumulation
? As GFR , BUN and serum creatinine levels
? BUN
? Not only by kidney failure but by protein intake, fever, corticosteroids, and catabolism
? N/V, lethargy, fatigue, impaired thought processes, and headaches occur
Electrolyte/acid?base imbalances
? Sodium
? May be normal or low
? Because of impaired excretion, sodium is retained
? Water is retained
? Edema
? Hypertension
? CHF
? Potassium
? Hyperkalemia
? Most serious electrolyte disorder in kidney disease
? Fatal dysrhythmias
? Calcium and phosphate alterations
? Magnesium alteration
? Metabolic acidosis
? Results from -Inability of kidneys to excrete acid load (primary ammonia)
Hematologic system
? Anemia
? Due to production of erythropoietin
? From of functioning renal tubular cells
? Bleeding tendencies
? Defect in platelet function
? Infection
? Changes in leukocyte function
? Altered immune response and function
? Diminished inflammatory response
? Anemia treatment
? Erythropoietin
? Administered IV or subcutaneously
? Increased hemoglobin and hematocrit in 2 to 3 weeks
? Side effect: Hypertension
? Iron supplements
? If plasma ferritin <100 ng/ml
? Side effect: Gastric irritation, constipation
? May make stool dark in color
? Folic acid supplements
? Needed for RBC formation
? Removed by dialysis
? Avoid blood transfusions
Cardiovascular system
? Hypertension
? Heart failure
? Left ventricular hypertrophy
? Peripheral edema
? Dysrhythmias
? Uremic pericarditis
Respiratory system
? Kussmaul respiration
? Dyspnea
? Pulmonary edema
? Uremic pleuritis
? Pleural effusion
? Predisposition to respiratory infections
? Depressed cough reflex
? "Uremic lung"
Gastrointestinal system
? Mucosal ulcerations
? Stomatitis
? Uremic fetor (urinous odor of the breath)
? GI bleeding
? Anorexia
? N/V
Neurologic system
? Expected as renal failure progresses
? Attributed to
? Increased nitrogenous waste products
? Electrolyte imbalances
? Metabolic acidosis
? Demyelination of nerve fibers
? Altered mental ability
? Seizures and Coma
? Dialysis encephalopathy
? Peripheral neuropathy
Restless leg syndrome
? Muscle twitching
? Irritability
? Decreased ability to concentrate
Reproductive system
? Infertility
? Experienced by both sexes
? Decreased libido
? Low sperm counts
? Sexual dysfunction
Musculoskeletal system
? Renal osteodystrophy
? Syndrome of skeletal changes
? Result of alterations in calcium and phosphate metabolism
? Weaken bones, increase fracture risk
? Two types associated with ESRD:
? Osteomalacia
? Osteitis fibrosa
? Phosphate intake restricted to <1000 mg/day
? Phosphate binders
? Calcium carbonate
? Bind phosphate in bowel and excreted
? Sevelamer hydrochloride
? Should be administered with each meal
? Side effect: Constipation
? Supplementing vitamin D
? Calcitriol l)
? Serum phosphate level must be lowered before administering calcium or
vitamin D
? Controlling secondary hyperparathyroidism
? Calcimimetic agents
? Sensitivity of calcium receptors in parathyroid glands
? Subtotal parathyroidectomy
Integumentary system
? Most noticeable change
? Yellow-gray discoloration of the skin
? Due to absorption/retention of urinary pigments
? Pruritus
? Uremic frost
? Dry, pale skin
? Dry, brittle hair
? Thin nails
? Petechiae
? Ecchymoses
Nutritional therapy
? Protein restriction
? 0.6 to 0.8 g/kg body weight/day
? Water restriction
? Intake depends on daily urine output
? Sodium restriction
? Diets vary from 2 to 4 g depending on degree of edema and hypertension
? Potassium restriction up to 2 to 4 g
? Phosphate restriction up to 1000 mg/day
Hemodialysis
? Artificial replacement in case of renal failure for removing excess
waste in form of solutes like urea and creatinine and water from the
blood.
GOALS
? Solute clearance
? Diffusive transport(countercurrent mechanism between blood flow
and diasylate)
? Convective transport (solvent drag and ultrafiltration)
? Fluid removal
Types of Dialysis
? continuous renal replacement therapies (CRRTs)
? slow low-efficiency dialysis (SLED)
? intermittent hemodialysis session
? Peritoneal dialysis
? continuous ambulatory peritoneal dialysis (CAPD)
? continuous cyclic peritoneal dialysis (CCPD)
ACCESS
? ARTERIOVENOUS FISTULA
? ARTERIOVENOUS GRAFT
? CENTRAL VENOUS CATHETER
COMPLICATIONS DURING HEMODIALYSIS
? Hypotension
? Increase the risk of hypotension,
? Including excessive ultrafiltration with inadequate compensatory vascular
filling,
? Impaired vasoactive or autonomic responses,
? Osmolar shifts,
? Overzealous use of antihypertensive agents,
? Reduced cardiac reserve.
? high-output cardiac failure due to shunting of blood through the dialysis
access in AVF patients
? Muscle cramps during dialysis are also a common complication
? excessively rapid volume removal (e.g., >10?12 mL/kg per hour)
? Anaphylactoid reactions to the dialyzer
? Type A reactions - IgE mediated intermediate hypersensitivity
reaction to ethylene oxide ,
? within minutes
? The type B reactions- complement activation and cytokine release
? symptom complex of nonspecific chest and back pain typically
occur several minutes into the dialysis run
This post was last modified on 07 April 2022