Stat Consult: Parenteral Nutrition Issues

Mechanical complications

• catheter or venous thrombosis
  • incidence varies (3.9% with peripherally inserted central catheters (PICC) to 38% with hemodialysis)
  • prophylactic heparin does not significantly reduce risk of thrombosis
  • PICC associated with higher rates of thrombophlebitis and difficulty of insertion compared with standard subclavian catheters.
• catheter occlusion 
  
  • more common with PICC than non-PICC increased risk with addition of syrups, medications with low pH, or oleaginous liquid medication
  • treatments include
    • 70% ethanol may clear lipid-related occlusion
    • 0.1-N sodium hydroxide for mineral or drug occlusion
    • issue plasminogen activator (tPA) for thrombus-related obstruction
• catheter-related infection (higher risk than enteral nutrition or IV dextrose)
• catheter dislodgement or fracture (rare)

Central vascular access complications

• pneumothorax
• hemothorax
• air embolism
• arterial puncture
• line malposition

Compatibility issues

• formation of precipitates (calcium gluconate may decrease risk)
• if high-dose vitamin C (up to 2,000 mg per day) needed, use separate infusion
• many medications not compatible with 3-in-1 parenteral nutrition solutions

Stability (degradation of nutritional components over time)

• not typically seen in acute care settings due to daily compounding of solutions
• more commonly seen in home care settings with bulk home delivery of solutions
• avoid degradation by adding vitamins just prior to infusions

Hyperglycemia

• primary cause is excess dextrose infusion
• balanced regimen should include 50%-60% of total calories from dextrose (infusion 4-5 mg/kg/minute optimal) 
• critically ill patients at increased risk
• advance dextrose concentration slowly to meet caloric goal with insulin adjustments per blood glucose levels
• consider using IV insulin drip instead of sliding scale in ICU

From the May 01, 2018 Issue of Clinical Advisor