Biochemical Parameters in Extremely Preterm Infants Receiving Mixed Lipid Emulsions.

OBJECTIVE

A mixture of soybean, medium-chain triglycerides, olive, and fish oils (SMOF) contains higher α-tocopherol and n-3 polyunsaturated fatty acids and lower phytosterol content compared with conventional soybean oil lipid emulsions (SOLE). We sought to characterize plasma total fatty acid profiles (FAPs) and assess the tolerability of long-term SMOF therapy in extremely preterm infants.

METHODS

We retrospectively evaluated infants born <28 weeks gestational age who received at least 30 consecutive days of SMOF between July 2016 and June 2019. We evaluated monthly FAPs and biochemical tolerance to SMOF using direct bilirubin (DB) and triglyceride (TG) levels. Growth parameters were evaluated longitudinally until discharge.

RESULTS

Sixteen patients with median gestational age 24 weeks (IQR, 23-25 weeks) received SMOF for median 76 days (IQR, 52-130 days). Fourteen patients had necrotizing enterocolitis (NEC) requiring surgical intervention and 15 patients received SOLE for median 19 days (IQR, 14-26 days) prior to switching to SMOF. Median docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels were elevated, whereas the remaining fatty acid levels fell within reported reference ranges. There were no incidents of essential fatty acid deficiency (triene to tetraene ratio >0.2) or hypertriglyceridemia (TG >200 mg/dL) with a general downtrend in DB after the first month on SMOF. All growth Z-scores declined throughout hospital stay.

CONCLUSIONS

Infants who received SMOF had a more pronounced elevation in DHA than EPA, of which the clinical significance remains unknown. Growth Z-scores declined with SMOF but were confounded by a high prevalence of surgically treated NEC.