Total Parenteral Nutrition (TPN)


General Nutritional Guidelines

Enteral Nutrition vs Total Parenteral Nutrition (TPN)

  • Clinical Efficacy
    • Systematic Review of Enteral vs Parenteral Nutrition in the ICU (Nutrition, 2004) [MEDLINE]
      • Enteral Nutrition Decreases Infectious Complications, as Compared to Parenteral Nutrition
      • Enteral Nutrition is Less Expensive than Parenteral Nutrition
    • British CALORIES Trial Comparing Early Enteral vs Parenteral Nutrition in the ICU (NEJM, 2014) [MEDLINE]: randomized trial in 33 English ICU’s comparing enteral vs parenteral nutrition (n = 2388)
      • No Difference in 30-day Mortality Between the Groups
      • Caloric Intake was Similar in the Groups, with the Target Intake Not Achieved in Most Patients
      • Significant Reduction in the Parenteral Group in Rates of Hypoglycemia (44 patients [3.7%] vs. 74 patients [6.2%]; P=0.006) and Vomiting (100 patients [8.4%] vs. 194 patients [16.2%]; P<0.001), as Compared to the Enteral Group
      • No Difference in Rate of Infectious Complications or Other Adverse Events
  • Recommendations (Society of Critical Care Medicine (SCCM) and American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) 2016 Guidelines) [MEDLINE]
    • Enteral Nutrition Should Be Used Over TPN (Quality of Evidence: Very Low-Low): enteral nutrition is associated with decreased infectious complications (pneumonia and central line infections in most patients/abdominal abscess in trauma patients) and decreased ICU length of stay
    • In Patients with Low Nutrition Risk (NRS 2002 ≤3 or NUTRIC score ≤5), Exclusive TPN Should Be Withheld for the First 7 Days Following ICU Admission, if PO Intake and Enteral Nutrition are Not Adequate/Possible (Quality of Evidence: Very Low)
    • In Patients with High Nutrition Risk (NRS 2002 ≥5 or NUTRIC score ≥5) or Severely Malnourished, Exclusive TPN Should Be Started as Soon as Possible Following ICU Admission, if PO Intake and Enteral Nutrition are Not Adequate/Possible (Quality of Evidence: Expert Consensus)
    • In Patients with Low or High Nutrition Risk, Supplemental TPN Should Be Considered AFter 7-10 Days if Unable to Meet >60% of Energy and Protein Requirements by Enteral Route Alone (Quality of Evidence: Moderate): initiating supplemental TPN prior to 7-10 days may be harmful

Indications for Total Parenteral Nutrition (TPN)


Administration

Caloric Content of Total Parenteral Nutrition Formulations

  • D5 (Peripheral/Central): 170 kcal/L
  • D10 (Peripheral/Central): 340 kcal/L
  • D25 (Central): 850 kcal/L
  • D30 (Central): 1020 kcal/L
  • D35 (Central): 1190 kcal/L

Typical Total Parenteral Nutrition (TPN) Formulations

  • NaCl: 40 mEq/L
  • KCl: none
  • Trace Elements: 3 mEq/L
  • NaAcet: 10 mEq/L
  • MVI: 1 amp/L
  • Protein Content of Amino Acids
    • 3.5% AA: 35 g protein/L
    • 4.25% AA: 42.5 g protein/L (170 kcal/L)
    • 5% AA: 50 g protein/L (200 kcal/L)
  • Calorie Content of Lipid Formulations
    • 10% Intralipid: 1100 kcal/L
    • 20% Intralipid: 2000 kcal/L

Initiating Total Parenteral Nutrition (TPN) in the High Risk or Severely Malnourished Patient

  • Recommendations (Society of Critical Care Medicine (SCCM) and American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) 2016 Guidelines) [MEDLINE]
    • Hypocaloric TPN Dosing (≤20 kcal/ kg/d or 80% of Estimated Energy Needs) with Adequate Protein (≥1.2 g Protein/kg/day) is Suggested Initially Over the First Week of Hospitalization in the ICU (Quality of Evidence: Low)

Trials Examining Use of Total Parenteral Nutrition (TPN) in the Intensive Care Unit

  • EPaNIC Trial Comparing Early vs Late Initiation of TPN (NEJM, 2011) [MEDLINE]: Belgian randomized multi-center trial comparing early initiation of TPN (European guidelines: within 48 hrs of ICU admission; n = 2312) with late initiation (American and Canadian guidelines: within 8 days of ICU admission; n = 2328) in adults in the ICU
    • No Difference in ICU Mortality Rate, Hospital Mortality, and 90-Day Mortality Rate Between the Groups
    • Late-Initiation Group Had a 6.3% Increase in Likelihood of Being Discharged Alive Earlier from the ICU and Hospital
    • Late-Initiation Group Had Fewer ICU Infections (22.8% vs. 26.2%, p = 0.008)
    • Late-Initiation Group Had a Lower Incidence of Cholestasis (p < 0.001)
    • Late-Initiation Group Had a Relative Reduction of 9.7% in the Proportion of Patients Requiring >2 Days of Mechanical Ventilation (p = 0.006)
    • Late-Initiation Group Had a Median Reduction of 3 Days in the Duration of Renal Replacement Therapy (p = 0.008)
    • Late-Initiation Group Had a Mean Reduction in Health Care Costs of About $1,600 (p = 0.04)
    • Late-Initiation Group Had No Decrease in Functional Status at Hospital Discharge
  • Study of Early Parenteral Nutrition in Critically Ill Patients with Short-Term Relative Contraindications to Early Enteral Nutrition (JAMA, 2013) [MEDLINE]: n = 1372 patients
    • No Impact on 60-Day Mortality Rate, as Compared to Standard Care
    • Early Parenteral Nutrition Strategy Resulted in Fewer Invasive Ventilation Days, But Had No Effect on ICU or Hospital Stay
  • Swiss Randomized Trial of Supplemental TPN in Critically Ill Patients (Lancet, 2013) [MEDLINE]: n = 305 patients
    • Supplemental TPN (in Addition to Enteral Nutrition) Starting 4 Days After ICU Admission Decreased Nosocomial Infection Rates
  • British CALORIES Trial Comparing Early Enteral vs Parenteral Nutrition in the ICU (NEJM, 2014) [MEDLINE]: randomized trial in 33 English ICU’s comparing enteral vs parenteral nutrition (n = 2388)
    • No Difference in 30-day Mortality Between the Groups
    • Caloric Intake was Similar in the Groups, with the Target Intake Not Achieved in Most Patients
    • Significant Reduction in the Parenteral Group in Rates of Hypoglycemia (44 patients [3.7%] vs. 74 patients [6.2%]; P=0.006) and Vomiting (100 patients [8.4%] vs. 194 patients [16.2%]; P<0.001), as Compared to the Enteral Group
    • No Difference in Rate of Infectious Complications or Other Adverse Events

Recommendations


Adverse Effects of Total Parenteral Nutrition (TPN)

Endocrinologic Adverse Effects

Infectious Adverse Effects

  • Increased Risk for Candidemia (see xxxx, [[Candida]])

Gastrointestinal Adverse Effects

  • Acalculous Cholecystitis (see Acalculous Cholecystitis, [[Acalculous Cholecystitis]])
    • Epidemiology: associated with opiate administration
  • Elevated Liver Function Tests (LFT’s) (see xxxx, [[xxxx]])

Other Adverse Effects

  • xxxx

References