Diet in renal diseases

Diet for patients with renal issues

1. Dietary Considerations
NURS3018
RENAL DISEASES

2. Learning Objectives
At the end of the lesson students should be able to:
Explain the principles involved in dietary management of
individuals with renal diseases
Identify nutrients, which are commonly restricted in renal
diseases
Utilize the food exchange list to plan a diet restricted in
sodium, potassium and protein
Plan a calcium and phosphorous modified diet

3. What is Renal Disease
“Renal failure results when the kidneys cannot adequately excrete
nitrogenous and metabolic wastes, either acutely, as a part of a clinical
illness, or chronically over years of declining renal function.”
(Brown, Compher, & ASPEN Board Directors, 2010)
Renal failure can occur rapidly because of sudden compromise in
renal function (vascular damage or infection) or more insidiously
because of chronic conditions such as HTN and DM.
(Tucker & Dauffenbach, 2011)
Renal Disease is reported to affect more than 26 million
Americans yearly.
The annual mortality for chronic dialysis patients exceeds 20%
making the mortality rate very high

4. Introduction
The kidneys are responsible for filtering the blood and
removing wastes for excretion in urine, maintains
homeostasis, produces enzymes and hormones that regulate
blood pressure, stimulate blood cell production and activate
Vitamin D.
Kidney failure will result will result in adverse health
conditions for which dietary interventions are important
The kidneys role in nutrition include-
Excreting end-products of protein metabolism
Fluid and electrolyte balance- excretion and conservation
Micronutrient metabolism

5. Types of Renal Failure
There are two types of renal failure: Acute and Chronic
Causes of acute renal failure: Illness, injury and surgery.
Further classified as prerenal, intrarenal (intrinsic) and postrenal.
The Acute Dialysis Quality Initiative Group recommended a
change in terminology from acute renal failure to acute kidney
injury (AKI).
The major causes of AKI include sepsis, trauma, hypotension,
intravenous contrast dye, & medications.
(Brown, Compher, & ASPEN Board Directors, 2010)

6. Causes of Acute Renal Failure- AKI
Prerenal factors: those that cause a sudden reduction on blood
flow to the kidney; they often involve severe stress such as heart
failure, shock or blood loss. Sepsis & hypotension may also cause
the condition
Intrarenal factors: those that damage kidney tissues, such as
infection, HTN, toxins, drugs and direct trauma. The
parenchyma- functional unit- including glomeruli, proximal
tubules and Loop of Henle are affected
Post renal factors :those that prevent excretion of urine due to
urinary tract obstructions- may be ureteral or bladder obstruction

7. Causes of Acute Renal Failure
Prerenal Factors
60-70 %of cases
Intrarenal Factors
25-40% of cases
Postrenal Factors
5-10% of cases
Low blood volume or pressure:
Hemorrhage, burns, sepsis or
shock, anaphylactic reactions,
nephrotic syndrome,
gastrointestinal losses, diuretics,
antihypertensive medications
Renal artery disorders: Blood
clots or emboli, stenosis,
aneurysm, trauma
Heart disorders: congestive
heart failure, heart attack,
arrhythmias
Vascular disorders: Sickle-cell
disease, diabetes mellitus,
transfusion reactions
Obstructions(within kidney):
Inflammation, tumors, stones,
scar tissue
Renal injury: Infections,
environmental contaminants,
drugs, medications, E coli food
poisoning
Obstuctions (ureter or bladder):
strictures, tumors, stones,
trauma
Prostate disorders: cancer or
hyperplasia
Renal vein thrombosis
Bladder disorders: Neurological
conditions, bladder rapture
Pregnancy

8. Chronic Renal Failure(CRF)
Characterized by gradual and irreversible deterioration in renal
function. The disease generally progress over many years without
symptoms.
Patients are usually diagnosed late in the course of illness after
kidney function has been lost.
Currently referred to as Chronic Kidney Disease (CKD).
The decline in renal function is measured by the Glomerular
Filtration Rate (GFR) that assesses the volume of ultrafiltrate
produced by the nephrons of both kidneys.
It can progress into uremia.
Has 5 stages- 1-4 relates to GFR decline but 5- relates to need for
renal replacement therapy.

9. Causes of Chronic Renal Failure
Diabetes mellitus- 43%
Hypertension- 26%
Other conditions include: inflammatory, immunological or
hereditary diseases
In a few case chronic renal failure follows acute renal failure.

10. Stages of Chronic Kidney Disease
Stage Description GFR(mL/min/1.73 m2)
I Kidney damage (protein in the urine) and
normal GFR
≥ 90
II Kidney damage and mild decrease in GFR60 – 89
III Moderate decrease in GFR 30 – 59
IV Severe decrease in GFR 15 – 30
V Kidney failure (dialysis or kidney
transplant needed)
< 15
GFR, glomerular filtration
rate

11. Macro/micronutrient changes in renal disease
Essentials of Diet Modification

12. Essentials of Diet Modification
Uraemia
Reduced kidney function can cause the body’s
nitrogen containing waste products to accumulate in
the blood. Catabolic patients will have additional
nitrogen waste.
Uraemic Patients usually display the following
symptoms:
fatigue, lethargy, confusion, headache, anorexia,
metallic taste in the mouth, nausea, vomiting and
diarrhea. In more serious cases rapid pulse, elevated
blood pressure, seizures and delirium or coma may
occur.

13. Essentials of Diet Modification
Prevention of Edema
Edema is a condition in which there is fluid accumulation in
tissues causing swelling. It may occur due to electrolyte
imbalances and inflammation. In AKI and CKD whole body
edema (anasarca) may occur.
Albumin is the major protein lost in urine.

14. Essentials of Diet Modification
Management of Edema
•Protein intake should fall between 0.8 and 1.0 gram per kg body
weight per day; in some cases the recommendation is as low as
0.6g/kg/d when GFR is -55 or lower
• e.g. a patient weighing 178 lb/81 kg would consume 64.8-82g
protein per day
•Energy intake s
•In patients with acute kidney injury, protein intake should be
adjusted according to catabolic rate, renal function, and dialysis
losses. (sustains weight and spares proteins)
•(Brown, Compher, & ASPEN Board Directors, 2010)

15. Acute Renal Failure
Principles of Diet Modification

16. Principles in Diet Modification (ARF)
Fluid restriction
Fluid status can be monitored by checking the following:
weight fluctuation,
blood pressure,
pulse rates
 appearance of the skin and mucous membrane
Another method is to measure serum sodium concentration: a
low sodium level suggests excessive fluid intake while a high
sodium level indicates inadequate intake.

17. Principles of Diet Modification
Fluid restriction
Fluid allowance is based on the presence of oliguria-urine less
than 500ml/d or anuria- urine less than 100ml/d
Generally fluid intake is limited to 1L per day- including
insensible losses, plus the total volume of any daily urine
Client teaching is important
Weight gain of more than 2-3 kg between dialysis may cause
overload
Including measuring units and containers
Include foods that are liquid at room temperature
Teach about thirst management

18. Principles in Diet Modification
Sodium/Potassium- Sodium restriction may prevent fluid
retention and hypertension. Oliguric patients may need to
limit sodium intake to 1-3g per day, lower intakes might be
necessary.
Potassium and phosphorus are restricted as well. Serum
electrolyte levels are monitored to determine appropriate
intake. K- 1-3g/d and P- 800mg- 1g/d. Dialyzed patients
can consume electrolytes more freely. This is recommended
with caution as the client may have challenges between
dialysis.

19. Principles in Diet Modification
Protein and Energy
ARF is a catabolic condition associated with hypermetabolism and
muscle wasting. Sufficient protein and energy must be provided to
preserve the body’s protein content. Where calorimetry is
unavailable, a patient is initially provided with 35kcal per kg (range
30-40kcal/kg/d) body weight per day, and body weight is monitored
to determine if adjustments are needed.
“Energy requirements in patients with renal disease should be
evaluated using indirect calorimetry when possible. If indirect
calorimetry is not possible, individualized assessment of energy intake
goals, as with other nutrition support patients, is recommended.”
(Brown, Compher, & ASPEN Board Directors, 2010)

20. Principles in Diet Modification
Protein contributes nitrogen, increasing the kidney’s workload
but it is needed to prevent negative nitrogen balance and
additional wasting. Dietary recommendation depends on the
degree of catabolism, kidney function and whether treatment
includes dialysis.
Overall nutritional status is to be measured including serum BUN
and Cr and adjustments made.
Dialysis may cause loss of amino acids and increased
requirements- assessing frequency of RRT is important
50% of protein intake should be from HBV proteins
(Tucker & Dauffenbach, 20110

21. Chronic Renal Failure
Principles of Diet Modification

22. Principles of Diet Modification
(Chronic Renal Failure)
Protein
A low protein diet is often prescribed for predialysis patients to
help slow down the progression of renal failure. An intake
between 0.6-0.8 g/kg body weight daily , just below RDA is
recommended.
Low protein diet produces fewer nitrogenous waste and
supplies less phosphorus than high-protein diets thus reducing
the risks associated with uremia and hyperphosphatemia
respectively.
To ensure that the low protein diet provides adequate amount
of amino acids, about 50% of the protein should be from high-
quality sources.

23. Principles of Diet Modification
(Chronic Renal Failure)
Lipids
Saturated fats and cholesterol should be restricted to help control
elevated blood lipids.
Unsaturated fatty foods should be utilized, eg. from nuts and
seeds, avocado, and soya bean products
Oily fish should be include to ensure adequate supply of essential
fatty acids.
The population has a characteristic high lipid profile and may be
associated with increased cardiovascular disease.
The management mirrors the management of any other client with
hyperlipidemia

24. Principles of Diet Modification
(Chronic Renal Failure)
Fluids and Sodium
As the disease progresses, the patient excretes less urine and cannot
handle a large amount of sodium and fluids. Suggested intakes are
based on total urine output, changes in body weight and blood
pressure and serum sodium levels. Foods with high water content
eg. Soups and frozen desserts contributes to fluid allowance in fluid
restricted diets

25. Principles of Diet Modification- CRF
Fluid restriction
Fluid allowance is based on the presence of oliguria-urine less
than 500ml/d or anuria- urine less than 100ml/d
Generally fluid intake is limited to 1L per day- including
insensible losses, plus the total volume of any daily urine
Client teaching is important, should include the following:
Weight gain of more than 2-3 kg between dialysis may cause
overload
Including measuring units and containers
Include foods that are liquid at room temperature
Teach about thirst management

26. Principles of Diet Modification
(Chronic Renal Failure)
Energy intake should be high enough to maintain a healthy
weight and prevent wasting. Foods and beverages of high
energy density are recommended. Malnourished patients
may require oral supplements or tube feeding to maintain
weight.
Peritoneal dialysis can contribute as much as 800kcal daily.
This should be accounted for when calculating intake. This
is because the solution used (monohydrous dextrose
contains carbohydrates)
The net absorption is 60% to 70% of dextrose from
peritoneal dialysis

27. Principles of Diet Modification
(Chronic Renal Failure)
Potassium- Before dialysis treatment begins, renal patients can
handle typical intake of potassium.
Allowances may be adjusted according to serum potassium levels.
Some people with diabetic nephropathy are at risk of
hyperkalemia and may need to limit potassium during the early
stages of the disease.
Supplementation may be required for patients using potassium
wasting diuretics.

28. Micronutrients and Renal Disease
The requirements are not well established.
Zinc, selenium and chromium are excreted by the kidneys,
Adequate diets should negate the need for supplementation
Iron and Zn status need to be assessed.
Blood loss during heamodialysis and loss of erythropoietin(EPO)
production may cause Fe def. anaemia. Iron profile is important-
treatment is synthetic EPO- recombinant human erythropoietin; oral
or IV iron may also be prescribed

29. Micronutrients and Renal Disease
High or normal Zn may be seen in CKD but low levels may be in
dialysis.
Supplementation should not be done unless deficiency is
demonstrated.
Carnitine is important of AA in Fatty acid metabolism and transport-
deficiency may occur with dialysis.
Carnitine supplementation benefits the client as it- reduces EPO
needs, reduces fatigue, improves exercise tolerance.

30. Dietary Recommendations for Chronic Renal Failure
Nutrients Predialysis Hemodialysis Peritoneal Dialysis
Energy (adult)(kcal/kg) <60 years ols:35
> 60 years old:30-35
<60 years ols:35 > 60 years
old:30-35
<60 years ols:35 > 60 years
old:30-35 (total kcal should
include those absorbedfrom
dialysate)
Protein (g/kg) (50% from high
quality protein
0.6-0.75 1.2 1.2-1.3
Fat As needed to maintain a healthy
lipid profile
As needed to maintain a healthy
lipid profile
As needed to maintain a healthy
lipid profile
Fluid (mL/day) Unrestricted if urine output is
normal
1000 plus urine output 1500-2000: monitoor closely
Sodium (mg/day) 2000 2000 2000
Potassium (mg/day) Individualized according to
laboratory values
2000-3000 3000-4000
Calcium (mg/day) 1200 <2000 from diet to medication<2000 from diet to medication
Phosphorus (mg/day) Individualized according to
laboratory values
800-1000 800-1000

31. Renal Calculi
An increase in fluid intake is recommended to maintain urine
volume between 2-3 litres. Fluids keep urine dilute so that
solutes cannot crystallize and form stones.
Twelve to sixteen (12-16) cups of fluid recommended per
day. More fluids for hot weather or for extremely active
persons.

32. Dietary strategies to manage: Renal
Calculi
Calcium Oxalate
Stones
Adjustment of calcium, oxalate, protein and sodium.
Calcium800-1000mg/day, Oxalate rich foods restricted,
moderate protein consumption, sodium restriction applies
Uric Acid StonesDiets restricted in purines may help to control urinary uric acid
levels. Dietary restriction of foods containing purines might be
difficult over a long term. All meats, seafood and poultry
contain purines.
Cystine and Struvite
Stones
High fluid intake can prevent the formation of cystine stones in
patients who excrete relatively low levels of cystine.
Preventing urinary tract infection is important in preventing
struvite stones.

33. References
Brown, R. O. , Compher, C., & ASPEN Board Directors.
(2010). A.S.P.E.N. Clinical guidelines: Nutrition support in adult
acute and chronic renal failure. Journal of Parenteral and Enteral
Nutrition.34: 366. DOI: 10.1177/0148607110374577
Rolfes S.R, Pinna K, &Whitney E. (2006) Understanding Normal
and Clinical Nutrition. 7
th
Ed. Thomson:Belmont , CA
Tucker, S. & Dauffenbach, V. (2011). Nutrition and diet therapy for
nurses. Boston, USA: Pearson.