Total Parenteral Nutrition

Aka: Total Parenteral Nutrition, TPN

1. Indications
   1. Bowel Obstruction
   2. Enteral feeding not possible or failed trial
   3. Short bowel syndrome
   4. Mesenteric Ischemia
   5. High output gastrointestinal fistula
   6. Gut failure or Malabsorption
   7. Transitional-Supplemental
   8. Perioperatively
      1. Start TPN 7-10 days before surgery to make difference
2. Complications: Parenteral Nutrition
   1. Biliary disease
   2. Osteoporosis (and Osteopenia)
   3. Catheter-related infection
   4. Central Line Placement related complications (e.g. Pneumothorax)
   5. Electrolyte disorders
   6. Hyperglycemia
   7. Hyperlipidemia
   8. Hepatic Steatosis (adults)
   9. Thrombosis
   10. Cholestasis (children)
   11. End-stage liver disease (50% of adults and children on lon-term parenteral nutrition)
       1. Chan (1999) Surgery 126(1): 28-34
3. Evaluation: Adult Energy Requirements
   1. Lean body wt (LBW)
      1. Male: 110 + 5 x(number of inches> 60) lbs
      2. Female: 100 + 5 x(number of inches> 60) lbs
   2. IF Obese (>130% LBW) then use adjusted weight
      1. (Actual-LBW) x 0.25 + LBW
   3. Basal Energy Expenditure (BEE) per 24 hours
      1. M: BEE=66 + (13.7xWt) + (5xHt) - (6.8xAge) = KCal
      2. F: BEE=655 + (9.6xWt) + (1.7xHt) - (4.7xAge) = KCal
      3. Adjust for depletion or disease
         1. 120-130% BEE is Maintenance
         2. 150% for stress and depletion
   4. Calorie requirement (per kg/day)
      1. Usually 30-35 KCal/kg/day
      2. Range = 20-40 Kcal/kg/day
   5. Adult Protein
      1. RDA = 0.8 g/kg/day
      2. Stress Adjustment
         1. 0.7-0.8 g/kg/d Maintenance, healthy, no stress
         2. 1.0-1.2 g/kg/d Mild stress
         3. 1.3-1.5 g/kg/d Moderate stress, repletion
         4. 1.5-2.0 g/kg/d Severe stress, burns
   6. Essential Fatty Acid Requirement
      1. Estimate 4-10% (2-4% linoleic) of daily calorie need
   7. Intravenous Electrolyte Requirements
      1. Electrolytes
         1. Sodium: 60-100 meq per 24 hours
         2. Potassium: 60-100 meq per 24 hours
         3. Calcium 10-15 meq per 24 hours
         4. Phosphorus 20-45 mMol per 24 hours
         5. Magnesium 10-20 mEq per 24 hours
4. Preparation: Adult 2-in-1 Parenteral Nutrition
   1. Sodium: 1-2 meq/kg
   2. Potassium: 1-2 meq/kg
   3. Calcium: 10-15 mEq
   4. Magnesium: 8-20 meq
   5. Phosphorus: 20-40 mmol
   6. Chloride: Adjusted per acid-base status
   7. Acetate: Adjusted per acid-base status
   8. Trace elements not routinely added (e.g. zinc, copper, Selenium, chromium, iron)
   9. MultiVitamin 12: 10 ml
   10. Fat emulsions 250 ml, 5x/week
   11. Regular Insulin as needed
5. Preparation: Child 2-in-1 Parenteral Nutrition (up to 50 kg or 110 pounds, then use adult dosing)
   1. Sodium: 2-5 meq/kg
   2. Potassium: 2-4 meq/kg
   3. Calcium: 2-4 mEq/kg for preterm newborns, 0.5 to 4 meq/kg for infants and children
   4. Magnesium: 0.3-0.5 meq/kg
   5. Phosphorus: 1-2 mmol/kg for preterm newborns, 0.5 -2.0 mmol/kg for infants and children
   6. Chloride: Adjusted per acid-base status
   7. Acetate: Adjusted per acid-base status
   8. Trace elements not routinely added (e.g. zinc, copper, Selenium, chromium, iron)
   9. Children's MultiVitamin formulation (1.5 ml for <1kg, 3.25 ml for 1-3 kg, 5 ml for >3 kg)
   10. Fat emulsions: Start 1 g/kg; increase every 1-2 days in increments of 0.5 to 1 g/kg/day
   11. Regular Insulin as needed
6. Labs
   1. Baseline
      1. Complete Blood Count
      2. Glucose
      3. Electrolytes including Magnesium, phosphate, calcium
      4. Renal Function tests
      5. Liver Function Tests including albumin
      6. Serum Iron
      7. Vitamin B12
      8. Vitamin D
      9. Zinc
      10. Copper
      11. Serum Folate
      12. INR
   2. Monitoring: Initially daily and may transition to weekly checks when stable
      1. Complete Blood Count
      2. Glucose (several times daily)
      3. Electrolytes including Magnesium, phosphate, calcium
      4. Renal Function tests
      5. Liver Function Tests including albumin
         1. Expect 2-3 fold over baseline with 10-14 days TPN
   3. Monitoring: periodic recheck when on longterm parenteral nutrition
      1. Vitamin B12
      2. Vitamin D
      3. Zinc
      4. Copper
      5. Serum Folate
7. References
   1. Bristrian (2006) Crit Care Med 34(5): 1525-31
   2. Kulick (2011) Am Fam Physician 83(2): 173-83