Sodium | Protein | Energy | Phosphate | Potassium | Fluid | Post-transplant | Malnutrition | Further info | QUIZ
Notes for students. Read in conjunction with the comprehensive Edren patient information pages on diet which include all that staff need to know - they need to be full if it's your diet for years. They also have more photos and cartoons than this page does. Download a pdf document of this page. Or go straight to the QUIZ
Plays vital role in regulation of fluid balance and blood pressure. Restriction is essential for compliance in fluid restricted patients.
Guidelines for general population= max 6g NaCl per day - but this is much more than is essential. An estimated 75% of salt intake comes from processed foods. All renal patients advised on a 'No Added Salt' (NAS) diet: 80-100mmols/day.
Essential for the growth and repair of body tissues
Protein-rich foods include: Meat, chicken, fish, eggs, cheese, yoghurts, nuts, pulses, meat substitutes (Note: some high protein foods contain high levels of phosphate and potassium)
Recommendation for protein varies according to stage of renal disease/ type of renal replacement therapy
Pre dialysis/ Conservative Management
Controlled protein intake (0.8-1g/kg/IBW)
- Helps to reduce phosphate load
- Prevents acidosis
- May reduce ureamic symptoms
- But must maintain nutritional status
- Use of low protein diets is controversial
Haemodialysis
Moderate protein requirements (1-1.2g/kg/IBW)
- Haemodialysis is a catabolic process
- Aim to replace protein lost during dialysis (~4g per session)
Peritoneal Dialysis
High protein requirements (1.1-1.5g/kg/IBW)
- Average peritoneal losses of 5-15g protein per day
- Increased losses in peritonitis
Adequate energy intake essential to optimise nutritional status
Pre dialysis/ Conservative Management
High energy requirements (30-35 kcal/kg/IBW)
- Can have raised metabolic rate
Haemodialysis
High-energy requirements (30-35 kcal/kg/IBW)
- Catabolic process raises metabolic rate
Peritoneal Dialysis
Moderate energy requirements (25-30/kg/IBW)
Account for calories absorbed from dialysis fluid (can be 70-270kcal/day)
Phosphate control essential for prevention and management of renal bone disease, arterial stiffening and vascular calcification.
Phosphate in the diet generally associated with intake of protein: Meat, fish, chicken, eggs, yoghurts, cheese, milk
Typical UK intakes of phosphate: - Men: 47mmol/day - Women: 36mmol/day
When GFR deteriorates to 25-30ml/min, phosphate retention can occur. Level of restriction depends on treatment mode, residual renal function, dietary intake, and biochemistry. Phosphate not very well dialysed - relatively large ion, with small gradient as plasma concentration low (1-2mmol/l).
Aim to maintain serum phosphate <1.8mmol/l. Control can be achieved via combination of:
Low phosphate diet
- Limit high phosphate foods (Cheese, yoghurt, eggs, nuts, milk, oily fish)
- May have to restrict phosphate intake to approx 30mmol/day.
- However, must maintain adequate protein intake
Phosphate binding medication:
Work in the stomach by binding the phosphate in foods - so should not be taken without food as will have no benefit
- Calcichew, Phosex (Calcium containing)
- Renagel, Alucap, Fosrenol, Lanthanum carbonate (Non-calcium containing)
Average intakes in the UK: - Men 84mmol/day -Women 66mmol/day
Restriction often required in renal patients for prevention and management of hyperkalaemia. Level of restriction based on treatment mode, dietary intake and biochemistry.
High Potassium Foods (more info on high potassium foods)
- Milk
- Potatoes and green vegetables (boiling reduces K+ content) , Potato crisps (Maize/corn better)
- Fruit (limit all fruit, fruit juice, dried fruit) and nuts
- Salt substitutes
- AND unfortunately: milk chocolate, coffee, toffee, liquorice, wine, beer, cider. But spirits are low in K+.
Restriction may be needed to prevent excessive fluid retention, depending on urine output. Impossible if salt intake high. Must count foods with a high fluid content (e.g. soup, ice cream, custard, gravy, jelly) in allowance. Difficult; aim to give practical tips: using smaller cups, sucking ice-cubes
Pre-dialysis
- Ensure adequate fluid intake (2-2.5L per day)
- May require restriction when nearing ESRF
Haemodialysis
- Varies depending on residual renal function
- Usually 500mls + PDUO
- Intradialytic weight gains of >2kg indicate excessive fluid intakes
Peritoneal Dialysis
- Varies depending on residual renal function and ultra filtration
- Tends to be less restricted than in haemodialysis
Post-op
- Ensure adequate nutritional intake post-op
- Ensure adequate intake of fluid and electrolytes during polyuric phase
- Dietary restrictions can usually be relaxed as function improves
Education on discharge
- Healthy eating
- Food safety, drug interactions
- Adequate calcium for bone preservation
- Potential to develop obesity, hyperlipideamia and steroid induced diabetes.
40-50% of HD and PD patients are malnourished. Affects morbidity and mortality rates. Very difficult to reverse once evident. Causes:
| Increased hospital admissions Infections Inadequate dialysis/ acidosis High nutritional requirement Limited fluid intake Intra-abdominal pressure in CAPD Social/ lifestyle |
Concurrent illness Uraemia Drugs Anaemia Restrictive diets Depression Economic factors |
Ascending scale of intervention:
Must also optimise medical management (dialysis adequacy, acidosis, infection)