Upload
gilbert-reynolds
View
216
Download
1
Embed Size (px)
Citation preview
Chronic Kidney
Disease
Heidi AndersonErica Bailey
Anai Villalobos Katie Pearce
Anatomy of the Kidney
2 major parts: Cortex Medulla
Functional Unit Nephrons
Renal Pyramid
Renal Pelvis
Ureter
Nephrons
1.) Glomerular Filtration
Fluids and solutes in the blood plasma of the glomerulus pass into the glomerular capsule (glomerular filtrate) Mechanisms to cause this fluid to be filtered is
High hydrostatic pressure of the blood in the glomerulus
Large number of pores
Substances present in the glomerular filtrate: water, electrolytes, glucose, AA, urea, hormones, and vitamins. -exclude large molecules that are in the blood.
GFR
The best way to measure levels of kidney function. GFR= urine volume x inulin conc. In urine
inulin conc. In plasma (mg/ml)
Best estimates of GFR: Inulin clearance Creatine clearance Plasma creatinine concentration Blood urea nitrogen (BUN)
2.) Tubular Reabsorption
Trans-epithelial transport
Most solutes reabsorped
completely
Urine volume is regulated by
the needs of the body
Active vs. Diffusion
Tm
3.) Tubular Secretion
Movement from the peritubular capillaries into the lumen of the tubule.
Main Substances secreted H+ K+ Some organic anions
http://ccn.aacnjournals.org/cgi/content/full/26/4/17/F1
Functions of the Kidney
Elimination of wastes, excess water and solutes, and conserves nutrients
Acid-base balance
Renin-angiotensin system
Erythropoietin release
Activation of Vitamin D
Elimination of Waste
Kidney receives 20% of cardiac output, which allows the filtering of approximately 1600 L/day of blood.
This is translated into 1.5 L of urine a day to be excreted, on average
The fluid filtered from the blood plasma is modified and reabsorbed as it travels along the tubules. The remainder finds its way into the ureter, which carries the urine to the bladder from each kidney.
Acid-Base Balance
Kidney is responsible for 2 major activities: Reabsorption of filtered bicarbonate Excretion of the fixed acids (acid anion and
associated H+)
Both of these processes involve secretion of H+ into the lumen by the renal tubule cells
Only the 2nd one leads to excretion of H+ from the body.
Acidosis vs. Alkalosis
Renin-
Angiotensin
System
Regulation
Of Blood
Pressure
Erythropoietin Release
EPO is a hormone primarily produced by the kidney
Occurs when a drop in blood oxygen level is perceived.
Used to treat anemia.
Glycosylated erythropoietin comes in 3 forms:
alpha (the most commonly used type in veterinary medicine),
beta (of similar clinical efficacy to alpha)
Darbepoetin (which is particularly heavily glycosylated and lasts the longest).
Vitamin D Activation
Parathyroid hormone is able to drive stored calcium and phosphorus from the bones as is vitamin D so these hormones are able to work in concert here but in the kidney they have different functions. In the kidney, while vitamin D saves both calcium and phosphate, parathyroid hormone causes only calcium to be saved and phophate to be dumped. There is a third hormone called “calcitonin” that keeps the blood calcium level from indefinitely rising. When blood calcium starts to get too high, calcitonin is released to begin storing calcium and phosphate back in the bones until it is needed again.
At Risk Populations
Racial Groups: African Americans Native Americans Hispanics Pacific Islanders
Risk Factors: Diabetes Hypertension Family history of kidney failure
Looking at Geographics
Hypertension
CKD
Genetics
The angiotensinogen promotor G(-6) allele lowers transcription and is inversely associated with hypertension.
the A1166C 3'-UTR variant of angiotensin II type 1 receptor (AT1R) has been associated with CKD.
The AT1R C1166 allele may increase susceptibility but only in the presence of hypertension.
What is CKD? CKD is the gradual loss of the kidney’s ability
to filter waste and fluid from the bloodstream.
Nephrons filter waste out of the blood.
Nephrons become damaged and lose their filtering ability overtime.
As more nephrons are damaged, the healthy ones work harder.
Kidneys become scarred or may shrink in size.
Etiology
• Diabetes is the number one cause of kidney disease, responsible for about 40% of all kidney failure.
• High blood pressure is the second cause, responsible for about 25%.
• About 12.2% of Native Americans over the age of 19 have type 2 diabetes.
Diabetes and high blood pressure are the leading causes of CKD.
Etiology-cont.
Other causes include:
- Glomerulonephritis (kidney inflammation)
- Genetic diseases (i.e. polycystic kidney disease)
- Autoimmune diseases (i.e. lupus)
- Birth defects
- Obstructions caused by problems like kidney stones or tumors
Pathophysiology
As the renal tissue loses function, the remaining tissue increases its performance
↓ renal function interferes with the ability to maintain fluid and electrolyte homeostasis.
↓ability to concentrate urine
↓ability to excrete phosphate, acid and K
↑creatinine and urea and ↓GFR
Heart failure can result from Na and water overload
Pathophysiology-cont.
↓production of calcitriol leads to hypocalcemia→osteopenia or osteomalacia.
↓excretion of phosphate leads to hyperphosphatemia
Secondary hyperparathyrodism is common→renal osteodystrophy.
Normochromic-normocytic anemia (Hct of 20-30%) caused by ↓erythropoietin production due to ↓functional renal mass.
Phosphorus Pathophysiology
Decreased renal function
Increased blood phosphorus
Decreased active vitamin D
Increase blood calcium levels
Decreased bone mass
Increased blood PTH
Cacliphylaxis
Cacliphylaxis
Deposition of calcium phosphate in soft tissues This occurs when the phosphorus-calcium
product is too high (greater than 4.5 (mmol/l)2
Cacliphylaxis is associated with CVD Calcium phosphate is deposited on heart
valves and blood vessels
Diagnosis
Based on laboratory testing of renal function:
- Creatinine
- GFR
- BUN
Urinalysis (check for protein, blood and WBC in urine-which should not be there).
Sometimes renal biopsy.
MRI or ultrasound to check the size.
LABS
Glomerular filtration rate (GFR) is the best measure of kidney function.
A doctor will order a blood test to measure the serum creatinine level. As kidney function ↓, blood levels of creatinine ↑.
Creatinine
It is a waste product that is passed through the kidneys.
A by-product formed by muscle contractions. It also comes from protein foods we eat.
↑creatinine may signal that the kidneys aren’t eliminating this waste, leaving it in the body.
Normal range: 0.8-1.4mg/dL
Glomerular Filtration Rate (GFR)
Measures the kidney function and the stage of CKD.
As the kidneys become more damaged, the GFR will decrease.
Normal range: >90, with little or no protein or albumin in the urine.
Blood Urea Nitrogen (BUN)
The BUN test measures the amount of urea in your bloodstream.
Urea is a waste product left over from the protein we eat, which is normally eliminated through the kidneys.
↑urea mean the kidneys are not getting rid of waste and it remains in the body.
Normal range: 7-20 mg/dL
S/SCKD is a silent, but devastating
disease. Azotemia
Uremia
↑↓urination (nocturia)
Fatigue/weakness
Nausea and vomiting
Bruising/bleeding
Uremic frost (crystals in and on skin)
S/S – cont.
Loss of appetite
Edema in feet, ankles, hands, or face
Back pain
Itching
Shortness of breath (fluid can build up I lungs)
Ammonia breath or taste in the mouth
5 Stages of CKD
Help doctors give the best treatment to patients
Each stage requires different tests and treatments
Stage GFR Level Description
Stage 1 90 mL/min or more
Healthy kidneys or kidney damage with normal or high GFR
Stage 2 60 to 89 mL/min Kidney damage and mild decrease in GFR
Stage 3 30 to 59 mL/min Moderate decrease in GFR
Stage 4 15 to 29 mL/min Severe decrease in GFR
Stage 5 Less than 15 mL/min or on dialysis
Kidney failure
Stage 1
GFR > 90 ml/min
Kidney damage
Normal or increased function
No symptoms of damaged kidney
People aren’t usually diagnosed unless they are being tested for something else
Stage 2
GFR 60-89 ml/min
Mild decrease in kidney function
This GFR is normal for some people
People with GFR >60 are still considered to have Chronic Kidney Disease if they have some kind of damage to their kidney
Stage 3
GFR 30-59 ml/min
Moderate decrease in kidney function
Uremia
Symptoms may start to develop
Stage 4
GFR 15-29 ml/min
Severe decrease in kidney function
Patients will start thinking about dialysis or transplant
Think about getting a fistula so it has time to mature
Stage 5
Less than 15 ml/min
Kidney failure with treatment
End stage renal disease
Kidneys are unable to remove waste and fluid from the body
Complications of CKD
Cardiovascular disease
Anemia
High blood pressure
Bone disease
Can CKD be Halted or Reversed?
Cannot be reversed
No known cure (other than kidney transplant)
Can be halted! Use preventative techniques to halt the
progression.
Prevention
Prevent and control high blood pressure
Prevent and control diabetes
Early diagnosis Routine physical examinations
Stop smoking
Decrease alcohol consumption
Hypertension Prevention/Control
Most important thing to prevent of CKD
Maintain Healthy weight
Exercise to raise your heart rate
Reduce Sodium in diet
Take Medication Can slow rate of kidney damage by 50%!
Diabetes prevention
Eat a healthy Diet Fiber, whole grains Fruits and vegetables
Maintain normal blood glucose levels
Exercise
Obtain and maintain healthy weight
Prevention Programs
National Kidney Foundation’s KEEP Free screening Educational materials Designed to raise awareness
Need a better global effort
Require a lot of man power and funds
Diabetes and Birth
Can lead to complications for the fetus as soon as the first 6-8 weeks of life CNS deformities Musculoskeletal deformities Congenital heart disease Spontaneous abortion
Large birth weights
Shoulder dystocia
Diabetes and Birth
Large birth weight If diabetes is not controlled Baby gets high blood sugar Baby makes more insulin Stores the extra calories as fat “overfed”
Compliance with Diabetes treatments and development of CKD
Study done showing that intensely treated diabetics were 21% less likely to have nephropathy.
Patients who more tightly control their blood sugar are less likely to have renal complications
The longer a patient is noncompliant with diabetes treatments, the greater risk he/she has of developing CKD.
Quality of Life
Physical Function
Social Activity
Energy
Cognition
Emotion (anxiety, fear, denial, anger, depression, etc)
Sleep patterns-sleep apnea
Health Perception
General Life Satisfaction
Life Expectancy
Mortality increases as kidney function decreases.
Leads to increased risk of CVD
Life expectancy of a 40- to 44-year-old white male in the general population in the US is more than 35 years.
Long Term Dialysis can add about 8 more years
Organizations/Support Groups
Organizations National Kidney Foundation American Kidney Fund
Support Groups Renal Support Network American Association of Kidney Patients
Medical Treatment
There is no cure to CKD, but there are ways to slow the progression of the disease: Control blood glucose
Insulin therapy Metformin Other diabetes medications
Medical Treatment—cont.
Control blood pressure ACE inhibitors ARBs Diuretics
MNT Decrease protein intake Decrease phosphorus intake
Phosphorus binders Decrease sodium intake
Effect of diet on progression
For diabetic patients, management of their diabetes can prevent or decrease the progression of CKD.
Managing blood pressure can also help to control the progression of CKD.
Cochrane Database study found that lower protein diets reduced “renal death” by 32% in non diabetic adults
MNT
Energy 30-35 kcal/kg IBW
Protein 0.6-1.0 g/kg IBW
Fluid Ad libitum
Sodium Variable, 2-3 g/day
Potassium Variable, usually ad libitum or increased to cover losses with diuretics
Phosphorus 0.8-1.2 g/day or 8-12 mg/kg IBW
MNT--ProteinUrine Output Percent HBV Protein
Recommendations
> 55 ml/min 60% 0.8 g/kg/day
25-55 ml/min 60% 0.8 g/kg/day
<25 ml/min 50% 0.6 g/kg/day *
*This can increase to 0.75 g/day if the patient cannot get 35 cal/kg IBW.
MNT—ProteinExcess protein in the diet
Excess ammonia in the blood
Increased stress on the kidney
More rapid kidney failure
MDRD Study
Kidney Failure Death Kidney Failure or Death
Low protein diet (.58 g/kg/day) 90.7% 23.3% 96.1%
Very low protein diet (.28 g/kg/day with .28 g/kg/day EAA)
87.3% 38.9% 95.2%
MNT—Sodium
Restriction of sodium to 2-3 grams/day. This may help decrease blood pressure . It may also decrease proteinuria.
MNT--potassium
In stages I-IV CKD, potassium intake may need to be increased or decreased depending on the lab values for the specific patient.
Fruits and vegetables are generally high in potassium. The potassium content can be decreased by
soaking vegetables in water.
MNT--Phosphorus
Phosphorus is normally excreted in the kidneys. In CKD, phosphorus can build up in the blood.
Depending on lab values, it may be necessary to decrease dietary intake of phosphorus.
High-Phosphorus Foods Dairy products Meat Nuts
MNT—Vitamin D
When serum active vitamin D is low, PTH is secreted. This causes increases in calcium and phosphorus which can lead to calciphylaxis.
Vitamin D supplementation is still controversial.
MNT--Carbohydrates
It is important for diabetic patients to manage their diabetes: Spread carbohydrates throughout the day. Eat at consistent times throughout the day.
Case Study--ET
24 YOF
Pima Indian
Dx with type 2 DM at 13 years old, poorly compliant
GFR decreasing over the past year
1 + pitting generalized edema
Lab ValuesParameter Normal Value Patient’s Value Rationale
Albumin 3.6-5.0 3.2 Albumin is being lost in the urine
Osmolality 275-295 400 Glucose is high
BUN 8-26 80 Indicates kidney dysfunction
Creatinine 0.6-1.3 1.5 Indicates kidney dysfunction
Cholesterol 140-199 443 High sat fat diet
HDL 40-85 37 High sat fat diet
LDL <130 132 High sat fat diet
Triglyceride 35-160 300 High sat fat diet
HbA1C 4.8-7.8 8.2 Glucose has been consistently too high
PES Statement
Excessive fat intake relating to eating too many high fat foods as evidenced by 24 hour recall and high blood lipid levels (chol: 443 mg/dl, LDL: 132 mg/dl, TG: 300 mg/dl).
Sample Diet
Pt weighs 63.6 kg
Recommended amounts:
.8 g protein/kg = 51 g
30-35 kcal/kg = 1908-2226 kcals
8-12 mg/kg phosphorus = 509-763 mg
3 g sodium restriction
Sample Diet
Breakfast Lunch
Apple juice - Taco: Toast w/ butter ground beef,
tortilla, Margarine onion, tomato, lettuce Peach - Grapes Rice krispies Milk
Sample Diet
Dinner Penne pasta Marinara Green beans Caesar salad
Romaine lettuce, croutons, tomato, dressing Rolls with butter
Sample Diet
Actual from Diet: Protein: 46 g Calories: 1954 kcals Phosphorus: 785 mg Sodium: 3111 mg