Controversies in the Use of Lipid Injectable Emulsion in Hospitalized Patients

Soybean oil-based lipid injectable emulsion (SO-based ILE) is an 18-carbon, ω-6 macronutrient providing a concentrated source of calories, which can be administered in or with parenteral nutrition to patients unable to tolerate or consume adequate enteral nutrition. Beyond the provision of energy, SO-based ILE provides linoleic and linolenic acid, 2 essential fatty acids necessary for the prevention of essential fatty acid deficiency. However, SO-based ILE with its high levels of ω-6 fatty acids, long-chain triglycerides, phospholipid emulsifiers, and glycerin has been associated with worsening clinical outcomes, including increase of infections, lengthier intensive care and hospital stay, and prolonged mechanical ventilation. Recognizing this, studies have investigated omitting SO-based ILE in the critically ill patient for the first 7 days to observe if clinical outcomes are improved. Unfortunately, there is extremely limited research, and what is available is controversial. National guidelines have analyzed the studies, and they too are challenged to define a clear, high quality of evidence recommendation. It is important for the healthcare clinician to understand the research around this controversy to make best decisions for their patients.