Diseases of the Renal System

KNH 413

CKD - Renal Replacement Therapy

Hemodialysis (HD) or Peritoneal Dialysis (PD)Type based on underlying kidney disease and co-

morbid factors

Both require selective, permeable membrane Allows passage of water and small molecules

CKD - Renal Replacement Therapy

Hemodialysis (HD)Membrane is manmade dialyzer Preferred access site – AVF, AVG Typical regimen

CKD - Renal Replacement Therapy

Peritoneal dialysis (PD)Lining of patient’s peritoneal wall is the

selective membrane Types

CAPD CCPD

Access via catheter into peritoneal cavity

Dwell time and number of exchanges

CKD - Stages 1 & 2Nutrition Therapy

Focus on co-morbid conditions: diabetes, hypertension, hyperlipidemia, progression of CVD

K/DOQI guidelines for GFR ≤ 20 SGA every 1–3 mo. Dietary interviews and food intake

Protein: .6-.75 g/kgEnergy: 30-35 kcal/kg

CKD - Stages 3 & 4Nutrition Therapy

See ADA guidelinesNutrition assessment recommendations Nutrient recommendations

Protein, energy, sodium, potassium, phosphorus, calcium, vitamins, minerals, fluid may need adjustment

Emphasize usual foods

CKD - Stages 3 & 4Outcome measures

Clinical Biochemical Anthropometrics Clinical signs and symptoms

Behavioral Meal planning, meeting nutrient needs, awareness of

food/drug interactions, exercise

CKD - Stage 5Nutrition Assessment

On dialysis – measures not different Dietary intake Biochemical: serum albumin

Goals: meet nutritional requirements, prevent malnutrition, minimize uremia, minimize complications

Maintain blood pressure, fluid status

© 2007 Thomson - Wadsworth

CKD - Stage 5Nutrition Intervention

HD – high in protein, control intake of potassium, phosphorus, fluids and sodium

PD – more liberalized; higher in pro., sodium, potassium and fluid, limit phosphorus

nutrients to monitor

CKD - Stage 5Nutrition Intervention

Protein - 1.2 g/kg (HD), at least 50% HBV

PD same except during peritonitis

CKD - Stage 5Nutrition Intervention

Energy to prevent catabolism; needs slightly higherPD - account for kcal in dialysateCaloric load 24-27 kcal/kg/day average intake

CKD - Stage 5Nutrition Intervention

Adjusted Edema-Free Body Weight should be used to calculate body weight for calculating protein and kcal For those < 95% or > 115% median standard weight

NHANESII For maintenance in HD and PD pts. Obtained postdialysis for HD pts., and after drainage for

PD patients

CKD - Stage 5Nutrition Intervention

Fat - increased risk for CAD and strokeHD typically have normal LDL, HDL, TGPD higher TC, LDL, TGRecommend TLC diet guidelines for both

CKD - Stage 5Nutrition Intervention

Fluid and Sodium highly individualized based on residual urine output and dialysis modality Interdialytic weight gain (HD) should not exceed 5% of

body weight 2 gram sodium diet Not more than 1 L fluid daily If urine output > 1 L/day sodium and fluid can be

liberalized to 2-4 g and 2 L

CKD - Stage 5Nutrition Intervention

Fluid and Sodium PD – based on ultrafiltration; 2 -2.5 kg fluid/day Fluid 2 L Sodium 2-4 g Fluid overload: shortness of breath, htn., CHF, edema

CKD - Stage 5Nutrition Intervention

PhosphorusHyperphospatemia - GFR 20-30 mL/minDietary phosphorus restriction: 800-1000 mg/day, <

17 mg/kg body IBWPhosphate binders; calcium saltsLimit calcium intake

© 2007 Thomson - Wadsworth

CKD - Stage 5Nutrition Intervention

Calcium requirements higher in CKDRestrict foods high in calciumTake supplements on empty stomachLimit to 2000 mg/day from all sources

CKD - Stage 5Nutrition Intervention

Vitamin SupplementationWater-soluble vitaminsDaily requirements “Renal” vitamins include B12, folic acid, vitamin C

Avoid high doses of vitamins A & CMay need vitamin K if on antibiotics

CKD - Stage 5Nutrition Intervention

Mineral supplementationAvoid Mg-containing phosphate binders, antacids, and

supplements IronZinc