PN Overview

Introduction

  • Presenter: Jordan Burton, Pediatric and Neonatal Clinical Pharmacy Specialist at UTMB Health, Galveston, Texas.

  • Focus of Presentation: Overview of Total Parenteral Nutrition (TPN), including proteins, carbohydrates, and fats.

  • Target Audience: Students preparing for rotations and future clinical practice.

Overview of Nutrition

  • Nutritional Needs: Essential for all individuals, regardless of age (pediatrics or adults).

  • Situations Arising for Parenteral Nutrition:

    • Patients unable to consume food due to illness or gastrointestinal complications.

    • Commonly used method for providing nutritional support is through intravenous nutrition (parenteral nutrition).

Total Parenteral Nutrition (TPN)

  • Definition: TPN is a method of supplying all nutritional needs of patients intravenously.

  • Continuous or Short-Term Use:

    • Can sustain life for an extended period or short duration as necessary.

    • Risk associated with long-term use opted against when possible.

  • Indications for Parenteral Nutrition (examples):

    • Neonates and pediatric patients:

    • Long-term NPO status.

    • Failure to thrive, prematurity, short gut syndrome, etc.

    • Adult patients:

    • Paralytic ileus, small bowel obstruction, GI fistulas, etc.

Components of TPN

Macronutrients

  • Definition: Nutrients required in larger quantities for energy (macronutrients) and include:

    1. Proteins (Amino Acids):

    • Available concentrations: 3.5% to 15%.

    • Energy content: Each gram provides 4 calories.

    • Importance in pediatrics: Critical for enhancing net protein accretions and reducing protein catabolism.

    1. Dextrose:

    • Function: Major source of calories in TPN.

    • Energy content: 1 gram yields 3.4 calories.

    • Concentration availability: Up to 70%.

    • Customized dosing based on glucose levels and patency of infusion line.

    1. Lipids (Fats):

    • Role: Provide concentrated calories and essential fatty acids.

    • Concentration: Supplies approximately 30% of non-protein calories; 10 calories per gram.

    • Caution with Soybean oil: Typically used but can lead to cholestasis and liver disease with long-term use.

  • Formulations:

    • Three-in-One TPN: Contains all three macronutrients in one solution.

    • Two-in-One TPN: Separates lipids from dextrose and amino acids, often used in pediatric and neonatal cases.

Micronutrients

  • Importance: Vital for metabolic processes and cellular functions.

  • Key Micronutrients:

    1. Electrolytes:

    • Essential examples include sodium, potassium, calcium, magnesium, phosphorus, chloride, and acetate.

    • Critical for acid-base balance, nerve function, and hydration.

    1. Trace Elements:

    • Include zinc, copper, manganese.

    • Necessary for enzymatic reactions and metabolic functions.

    • Dosing may depend on patient-specific conditions and needs.

    • Example: Limit or omit copper in patients with hepatic issues.

Administration Considerations

  • Individualization: TPN formulations require customization based on patient age and clinical condition.

  • Volume and Caloric Needs:

    • General principles for caloric intake may vary (e.g., burn patients requiring increased calories).

  • Osmolarity Calculation:

    • Solutions up to 900 milliosmoles per liter can be given peripherally.

    • Above this concentration, central line administration is recommended.

  • Compatibility Issues:

    • Specific timing for adding components (e.g., calcium and phosphorus) to avoid precipitation.

    • Changes in amino acids, pH, and temperature influence TPN stability.

  • Monitoring Considerations:

    • Essential for infusion sites to avoid infiltration.

    • Regular evaluation of metabolic panels for electrolyte and organ functions (renal and hepatic) necessary.

Guidelines and Recommendations

  • ASPEN Guidelines: The American Society for Parenteral and Enteral Nutrition provides established guidelines specific to patient populations and disease conditions.

  • Importance of Continued Learning: These guidelines serve as critical resources for clinicians to optimize patient care relating to parenteral nutrition.