Most Common Complications of Enteral and Parenteral Feeding
The most common complication of parenteral nutrition is catheter-related sepsis (Answer A), while diarrhea is the most common complication of enteral nutrition (Answer E).
Parenteral Nutrition Complications
Catheter-Related Sepsis: The Primary Concern
Central line-associated bloodstream infections (CLABSIs) represent the most common and serious complication of parenteral nutrition, causing significant morbidity and mortality 1, 2. The evidence consistently demonstrates this across multiple guidelines:
- Incidence rates range from 3.8-11.3 infections per 1000 catheter days in pediatric patients 1
- In home parenteral nutrition patients, rates vary between 0.34-3.94 episodes per catheter year 1
- Catheter-related sepsis is explicitly identified as "the most prevalent complication" inherent to the parenteral route 1
The major pathogens include Gram-positive coagulase-negative staphylococci (30-40%), Gram-positive staphylococci (7.7-15%), Gram-negative bacteria (30-40%), and fungi (4.6-6%) 1.
Other Significant Parenteral Nutrition Complications
Metabolic complications occur frequently, particularly hyperglycemia, which is more common with parenteral than enteral nutrition 1. Overfeeding represents a major risk factor for metabolic disturbances 1.
Elevated liver transaminases and hepatobiliary complications (Answer C) are indeed prevalent, affecting 20-75% of adults on long-term parenteral nutrition 3. However, these are secondary in frequency to catheter-related sepsis 1, 2.
Enteral Nutrition Complications
Diarrhea: The Most Frequent Issue
Gastrointestinal disturbances, particularly diarrhea, are the most frequently encountered complications of enteral feeding 4. Multiple factors contribute to diarrhea in tube-fed patients:
- Concomitant drug therapy 4
- Malnutrition/hypoalbuminemia 4
- Formula-related factors (lactose content, osmolality) 4
- Bacterial contamination 4
Mechanical complications follow as the second most common category, then metabolic complications 4.
Comparative Risk Profile
Parenteral nutrition-related morbidity is consistently higher than enteral feeding 1. The evidence demonstrates:
- Higher in-hospital mortality with parenteral nutrition (OR 2.5; 95% CI: 1.93-3.24) 1
- Increased length of stay (13.7 vs. 5.7 days) 1
- Significantly higher hospital charges 1
Addressing the Other Answer Choices
Intestinal villous atrophy (Answer B) occurs with parenteral nutrition due to lack of enteral stimulation 3, but this is not the most common complication—it is a structural change that develops over time rather than an acute complication.
Hyperosmolar non-ketotic coma (Answer D) is a rare metabolic complication that can occur with overfeeding and severe hyperglycemia 1, but it is far less common than catheter-related sepsis or diarrhea.
Clinical Pitfalls to Avoid
- Do not assume all infections in parenteral nutrition patients are catheter-related—always rule out alternative sources before diagnosing CLABSI 1
- Prevention protocols can reduce catheter infection rates to less than 1 per 1000 catheter-days, emphasizing the importance of proper catheter care 1
- For enteral nutrition, do not automatically attribute diarrhea to the formula—systematically evaluate medications, albumin levels, and contamination 4