Total Parenteral Nutrition
TPN is a nutrient source that may be used in pregnant women who suffer from severe hyperemesis or when there is a lack of absorption of adequate nutrients. The severe nutritional deprivation caused by hyperemesis is preferably treated with enteral hyperalimentation, but if the patient cannot tolerate this and vomits after feeding, the risk of aspiration increases. TPN has been used in other conditions to sustain pregnancies, such as jejunoileal bypass, diabetes, and Crohn disease. TPN is a nonprotein calorie source, usually glucose or lipid emulsions, that provides utilizable nitrogen, electrolytes, trace elements, water, and fat-soluble vitamins. This source of calories prevents ketosis, which develops from fatty acid metabolism and may have adverse effects on the fetus.