Intravenous fat emulsion

Approved Indications:

• Parenteral Nutrition (PN):
• As a concentrated source of calories and essential fatty acids for patients who cannot receive adequate nutrition orally or enterally.
• Used as part of Total Parenteral Nutrition (TPN) with amino acids, dextrose, electrolytes, vitamins, and trace elements.
• Prevention and Treatment of Essential Fatty Acid Deficiency (EFAD):
• In long-term PN-dependent patients to avoid EFAD.
• Pediatric Nutrition:
• For term and preterm neonates, infants, and children requiring parenteral nutrition.

Clinically Accepted Off-Label Uses:

• Critical Care Caloric Support:
• For critically ill patients unable to tolerate enteral feeding.
• Specialized Lipid-Based Drug Carriers:
• As a vehicle for certain lipid-soluble drugs in hospital settings.

Route:
Intravenous infusion only — central or peripheral vein (depending on osmolarity and formulation).

Adults:

• Initial: 1 g/kg/day
• Titration: Increase by 0.5–1 g/kg/day as tolerated.
• Usual Maintenance: 1–2 g/kg/day
• Maximum: 2.5 g/kg/day (infusion rate ≤0.11 g/kg/hour)

Pediatric:

• Preterm & Term Neonates: Start at 0.5–1 g/kg/day; increase gradually to max 3 g/kg/day.
• Children >1 Year: 1–3 g/kg/day

Elderly:

• Same as adults but initiate at lower end of dosing range; monitor metabolic tolerance.

Special Populations:

• Hepatic/Renal Impairment: Start at reduced dose; monitor triglycerides, liver enzymes.
• Critically Ill: Start lower; titrate slowly to caloric target.

Administration Guidelines:

• Mix aseptically if combined in PN admixtures.
• Use in-line filters when part of a PN mixture.
• Infuse over 12–24 hours; avoid rapid bolus.
• Do not use if emulsion shows separation, discoloration, or particles.

Intravenous fat emulsions deliver triglycerides (long-chain and/or medium-chain), which are hydrolyzed by lipoprotein lipase to free fatty acids and glycerol. These fatty acids are rapidly oxidized in cells to produce energy (9 kcal/g) or incorporated into cell membranes. They also provide essential fatty acids — linoleic acid (omega-6) and α-linolenic acid (omega-3) — necessary for eicosanoid synthesis and maintaining membrane fluidity, thereby preventing EFAD and supporting metabolic and structural cellular functions.

• Absorption: Direct IV delivery; no gastrointestinal absorption required.
• Distribution: Incorporated into plasma lipoproteins; distributed to muscle, adipose tissue, and liver.
• Metabolism: Hydrolyzed by lipoprotein lipase; fatty acids oxidized in mitochondria or stored.
• Elimination: Oxidized fatty acids released as CO₂ via respiration; minimal urinary excretion.
• Onset: Immediate metabolic availability upon infusion.
• Half-life: ~30–60 minutes for triglyceride clearance in healthy individuals.

• Pregnancy: No formal FDA category; human data limited. Use only if benefits outweigh risks and under specialist supervision.
• Lactation: Unknown if excreted in breast milk when administered intravenously; likely minimal. May be used if clinically indicated, with infant monitoring for lipid tolerance.

• Primary Class: Parenteral Nutritional Supplement
• Subclass: Intravenous Lipid Emulsion

• Hypersensitivity to egg, soybean, fish, or peanut proteins (depending on formulation).
• Severe hyperlipidemia or disorders of lipid metabolism.
• Acute severe shock or unstable hemodynamic status.
• Pathological hyperbilirubinemia in neonates without monitoring.
• Known allergy to formulation components.

• Metabolic Risks: Hypertriglyceridemia, fat overload syndrome (fever, hepatosplenomegaly, anemia, coagulopathy, coma).
• Liver Effects: May cause or worsen cholestasis, steatosis.
• Infection Risk: PN admixtures can be a bacterial growth medium; maintain aseptic technique.
• Respiratory Caution: Avoid over-infusion to prevent pulmonary fat embolism.
• Neonates: Monitor for hyperbilirubinemia and cholestasis.
• Regularly monitor triglycerides, liver function, coagulation profile, and blood glucose.

Common:

• Fever, chills
• Nausea, vomiting
• Headache
• Flushing

Less Common:

• Elevated liver enzymes
• Hypertriglyceridemia
• Local phlebitis

Serious (Rare):

• Anaphylaxis (protein allergy)
• Fat overload syndrome
• Acute respiratory distress
• Pulmonary embolism
• Coagulopathy

• Heparin: Increases lipoprotein lipase release, enhancing lipid clearance temporarily.
• Insulin: Alters lipid metabolism, promoting fat storage.
• Other PN Components: Must ensure compatibility; physical separation of phases can occur.
• Alcohol (chronic use): May impair lipid metabolism.
• No major CYP450 enzyme-mediated interactions reported.

• PN guidelines recommend initiating lipid emulsions within 24–48 hours of PN initiation in patients without contraindications.
• Fish oil–containing emulsions increasingly used to reduce liver complications and inflammation in long-term PN.
• Emphasis on weekly triglyceride monitoring for stable PN patients; daily in unstable or critically ill patients.

• Store at 20°C–25°C (68°F–77°F).
• Do not freeze — discard if frozen.
• Protect from light.
• After spiking or mixing, use immediately or refrigerate (2°C–8°C) and use within 24 hours.
• Shake gently; discard if phase separation, oil droplets, or particles are visible.