Do you need to hold feeding during Sustained Low-Efficiency Dialysis (SLED)?

Feeding During SLED: No Need to Hold

You do not need to hold enteral feeding during Sustained Low-Efficiency Dialysis (SLED). In fact, maintaining nutrition during SLED is associated with improved outcomes, and the extended duration of SLED treatments (typically 8-12 hours) makes continuous nutritional support particularly important for critically ill patients.

Evidence Supporting Continued Feeding During SLED

The strongest evidence comes from a study of 199 critically ill cancer patients on continuous SLED (C-SLED), which demonstrated that administration of total parenteral nutrition (TPN) was associated with lower mortality 1. In the subset of 129 patients who received C-SLED for at least 48 hours, those with higher blood urea nitrogen levels—which were associated with higher TPN infusion—had a lower mortality risk, suggesting a direct link between nutrition and survival during SLED 1.

Practical Feeding Approach During SLED

Continuous Feeding is Preferred

• Use continuous pump feeding rather than bolus feeding during SLED sessions, as continuous feeding reduces gastrointestinal discomfort and maximizes nutrition absorption when absorptive capacity is diminished 2
• Continuous feeding is particularly appropriate for critically ill patients to prevent enteral nutrition-related complications 3
• The 8-12 hour duration of typical SLED treatments (median 50 hours total therapy) allows for substantial nutritional delivery without interruption 1, 4

Hemodynamic Considerations

• SLED maintains mean arterial pressure despite higher ultrafiltration rates and actually allows for reduced vasopressor use 1
• Hemodynamic stability is maintained during most SLED treatments, with prescribed ultrafiltration goals achieved in most cases 4
• Only 24.3% of SLED sessions required therapeutic intervention for hypotension (fluids and/or vasopressor increase), and only 2 sessions required interruption for refractory hypotension 5

Monitoring Requirements During Combined SLED and Feeding

Electrolyte Surveillance

Close monitoring of fluid, glucose, sodium, potassium, magnesium, calcium, and phosphate status is essential in the first few days after starting enteral tube feeding, particularly in critically ill patients 6, 2

SLED-Specific Electrolyte Losses

• Mild hypophosphatemia and/or hypokalemia requiring supplementation were observed in 25 SLED treatments, with mean phosphate removal of 1.5 g per treatment 4
• Water-soluble vitamin losses occur in approximately 90% of patients within 5-7 days of continuous renal replacement therapy (CRRT), and SLED shares similar characteristics 6
• Micronutrient supplementation should be initiated after 5-7 days in patients receiving SLED, with adequate amounts of all essential trace elements and vitamins supplied to prevent deficiencies 6

Nutritional Targets During SLED

Energy and Protein Goals

• Target 25-30 kcal/kg/day for energy and 1 g/kg/day for protein 6
• If no expert advice is available, 30 ml/kg/day of standard 1 kcal/ml feed is often appropriate, though this may be excessive in undernourished or metabolically unstable patients 6
• Avoid high-dose protein provision (>1.2 g/kg/day) in patients with acute kidney injury and high SOFA scores (≥9) 6

Refeeding Syndrome Risk

• Very undernourished patients should start at rates of <10 kcal/kg/day to prevent refeeding syndrome 6
• For patients at risk of refeeding syndrome, energy provision should be reduced to 15-20 non-protein kcal/kg per day 2
• Life-threatening problems due to refeeding syndrome are particularly common in the very malnourished, with risks also from overfeeding shortly after major surgery or during major sepsis and/or multiorgan failure 6

Common Pitfalls to Avoid

Do not interrupt feeding unnecessarily during SLED sessions. The only absolute contraindications to enteral nutrition in critically ill patients are uncontrolled shock, uncontrolled hypoxemia and acidosis, uncontrolled upper GI bleeding, gastric aspirate >500 ml/6 hours, bowel ischemia, bowel obstruction, abdominal compartment syndrome, and high-output fistula without distal feeding access 6.

Do not assume SLED requires the same feeding restrictions as intermittent hemodialysis. SLED's extended duration and hemodynamic stability make it more compatible with continuous nutritional support than traditional intermittent hemodialysis 1, 4.