Special Oligoelement Requirements in Acute Liver Failure
In patients with acute liver failure, trace elements should be monitored and supplemented, with special attention given to selenium, zinc, and copper due to increased requirements and potential deficiencies that can impact morbidity and mortality. 1
Key Trace Element Requirements
Critical Trace Elements to Monitor and Supplement
- Selenium: Often depleted in acute liver failure
- Zinc: Frequently deficient and associated with worsened encephalopathy
- Copper: Requires monitoring as effluent losses can exceed nutritional intake 1
Recommended Supplementation Approach
- Selenium: Consider supplementation of up to 100 μg/day 1
- Zinc: Supplementation of 50 mg/day elemental zinc may be required 1
- Copper: Approximately 3 mg/day intravenously when continuous kidney replacement therapy (CKRT) is required for more than two weeks 1
Water-Soluble Vitamins
Water-soluble vitamins should also be monitored and supplemented, with particular attention to:
- Vitamin C: Consider supplementation of 100 mg/day 1
- Folate: Monitor and replace due to potential losses
- Thiamine: Critical to administer before initiating nutritional therapy to prevent Wernicke's encephalopathy 1, 2
Nutritional Support Considerations
Protein Requirements
- Do not restrict protein in acute liver failure patients 2
- Provide 1.2-1.5 g/kg body weight per day of protein 1, 2
- For obese patients (BMI ≥30), consider 2.0 g/kg body weight per day 2
Energy Requirements
- Target 25-35 kcal/kg body weight per day 2
- For obese patients, aim for 25 kcal/kg body weight per day 2
Monitoring Protocol
- Trace Elements: Monitor serum levels, particularly when kidney replacement therapy is used 1
- Electrolytes: Monitor phosphorus, potassium, and magnesium every 6-12 hours initially 2
- Arterial Ammonia: Monitor when initiating protein administration, especially in severe hyper-acute disease 2
Special Considerations
Kidney Replacement Therapy
Patients on continuous kidney replacement therapy (CKRT) are at particularly high risk for trace element deficiencies due to:
- Increased utilization in critical illness
- Losses in effluent fluid
- Adsorption to hemofilters 1
These patients require additional supplementation beyond standard amounts provided in parenteral nutrition 1.
Refeeding Risk
Patients with acute liver failure are at risk for refeeding syndrome due to:
- Pre-existing malnutrition
- Altered metabolism
- Electrolyte imbalances
Administer thiamine before initiating nutritional therapy and closely monitor electrolytes 1, 2.
Practical Approach to Supplementation
- Initial Assessment: Evaluate nutritional status and determine route of nutrition (oral, enteral, or parenteral)
- Baseline Supplementation: Provide water-soluble and fat-soluble vitamins as well as trace elements from the beginning of nutritional support 1
- Monitoring: Check serum levels of trace elements, particularly in prolonged illness or when CKRT is used
- Adjustment: Individualize supplementation based on serum levels and clinical response
By addressing trace element requirements early and aggressively in acute liver failure, you can help mitigate complications and potentially improve outcomes in this critically ill population.