Vascular Access, Nutrition, and Pharmacotherapy
Vascular Access
Umbilical artery/vein catheters At birth, the umbilical cord contains two arteries and one vein — blood vessels that, in a premature or critically ill newborn, provide a remarkably convenient and relatively painless route for placing small plastic tubes (catheters) directly into the baby’s central circulation. An umbilical vein catheter can be used to deliver fluids, nutrition, and medications directly into the large vein near the heart, while an umbilical artery catheter allows continuous blood pressure monitoring and easy blood sampling without repeated needle sticks. These catheters can typically be placed within hours of birth and remain usable for days to weeks.
Peripheral artery/vein catheters When central access through the umbilical vessels is not available or appropriate, small catheters can be placed in the tiny veins or arteries visible at the surface of a baby’s hands, feet, scalp, or inner wrists. A peripheral intravenous (IV) catheter in a vein is the most common route for giving fluids and medications to any hospitalized patient, including newborns. A peripheral arterial catheter, placed in a small artery (often at the wrist), allows continuous beat-by-beat blood pressure measurement and painless blood sampling, similar in function to an umbilical artery catheter but placed in a limb rather than the umbilical cord.
Central venous catheters Some medications and concentrated nutritional solutions are too irritating to be safely given through small peripheral veins and must be delivered through a catheter whose tip sits in one of the large veins near the heart. In newborns. A common approach is the PICC line (peripherally inserted central catheter), a very fine, flexible tube threaded from a surface vein in the arm or leg all the way up into the central circulation. Central lines allow the safe delivery of high-concentration nutrition (TPN), certain drugs, and blood products over extended periods, and are a cornerstone of care for premature infants who cannot yet absorb enough nutrition through their digestive systems.
Infusion and syringe pumps Electronic pumps are used in the NICU to deliver fluids, nutrition, and medications at extremely precise rates — often measured in fractions of a milliliter per hour — that would be impossible to achieve by gravity drip or manual injection. Syringe pumps hold a standard syringe and push the plunger forward at a programmed rate, while larger infusion pumps manage bags of fluid. Because premature babies are so small, even tiny errors in fluid delivery can have significant consequences, and these pumps provide the accuracy and consistency that safe NICU care demands around the clock.
Nutritional Support
Parenteral nutrition Parenteral nutrition (PN) — sometimes called TPN, for total parenteral nutrition — refers to the delivery of a complete nutritional solution directly into the bloodstream through a central venous catheter, bypassing the digestive system entirely. The solution contains precisely calculated amounts of sugar (glucose), protein (amino acids), fats (lipid emulsion), vitamins, minerals, and trace elements. This is essential for extremely premature infants, who are too immature for their intestines to absorb adequate nutrition, and for infants recovering from intestinal surgery. While lifesaving, prolonged PN carries risks including liver disease, infection, and metabolic complications, so the goal is always to transition to feeding through the gut as quickly as possible.
Enteral feeding techniques Enteral feeding means delivering nutrition directly into the stomach or intestine through a tube, even when an infant cannot yet coordinate the suck-swallow-breathe sequence necessary for bottle or breast feeding. A thin, soft feeding tube passed through the nose or mouth and into the stomach allows measured volumes of breast milk or formula to be delivered continuously or in periodic small boluses. Beginning enteral feeds — even in tiny amounts called “trophic feeds” or “gut priming” — as early as possible promotes intestinal maturation, reduces complications of prolonged parenteral nutrition, and helps the gut develop the capacity to absorb progressively larger volumes of nutrition.
Special formulas While breast milk is strongly preferred for premature and sick newborns whenever possible, commercial formulas designed specifically for premature infants are available and are used when breast milk is unavailable or insufficient. These formulas are engineered to provide higher concentrations of protein, calories, calcium, phosphorus, and other nutrients than standard infant formula, reflecting the greater nutritional requirements and the smaller stomach volumes of premature babies. Some specialized formulas are also designed for infants with specific medical conditions, such as poor fat absorption, cow’s milk protein allergy, or rare metabolic disorders.
Breast milk supplements (fortifiers) Even human breast milk — while ideal in many ways — does not contain sufficient protein, calcium, phosphorus, and certain other nutrients to support the rapid growth demands of a very premature infant. Breast milk fortifiers are powdered or liquid supplements added directly to expressed breast milk before it is given to the baby, boosting its nutritional density while preserving the many immune and developmental benefits of human milk. This allows premature infants to receive the best of both worlds: the biological advantages of mother’s milk and the additional nutrients needed to grow at rates approaching those achieved in the womb.
Vitamins Newborns — particularly premature ones — are born with limited vitamin stores and have ongoing needs that their immature digestive systems may not be able to meet through feeds alone. Vitamin D is essential for bone development and calcium absorption, and deficiency causes rickets; vitamin K is necessary for normal blood clotting and is routinely given by injection to all newborns at birth; vitamins A, C, E, and the B vitamins serve a variety of metabolic and developmental functions. Supplemental vitamins are a routine part of the NICU nutritional regimen, with doses and formulations adjusted for gestational age and the volume of feeds a baby is tolerating.
Minerals Calcium and phosphorus are the primary building blocks of bone, and premature infants — who miss the period of maximum mineral transfer from mother to fetus that occurs in the last trimester — are at significant risk for metabolic bone disease (sometimes called rickets of prematurity) if not provided adequate mineral supplementation. Sodium, potassium, and chloride are electrolytes essential for maintaining normal fluid balance, nerve function, and countless cellular processes, and their levels are carefully monitored and supplemented based on laboratory results. Iron is essential for red blood cell production and brain development and is routinely supplemented in premature infants.
Trace elements In addition to major minerals, the body requires tiny amounts of numerous other elements — zinc, copper, selenium, manganese, iodine, chromium, and others — that serve as components of enzymes and other critical molecules involved in metabolism, immune function, antioxidant defense, and growth. These trace elements must be included in parenteral nutrition solutions for infants receiving IV nutrition and are present in human breast milk and supplemented formulas for those receiving enteral feeds. Deficiencies of specific trace elements can cause distinct and recognizable medical syndromes, making their provision an important but often overlooked aspect of neonatal nutritional care.
Blood Products
Red blood cells Red blood cells (RBCs) carry oxygen from the lungs to all the body’s tissues, and premature infants are particularly prone to anemia (low red blood cell count) for several reasons: they are born with lower reserves than term infants, their red cells have a shorter lifespan, their bone marrow produces new cells slowly, and blood drawn for laboratory testing — though minimized — still represents a significant loss relative to their tiny blood volumes. When anemia becomes severe enough to compromise oxygen delivery, a transfusion of packed red blood cells can rapidly restore the blood’s oxygen-carrying capacity, typically producing a visible improvement in the baby’s clinical status within hours.
White blood cells (granulocytes) Transfusions of white blood cells — specifically the infection-fighting cells called granulocytes or neutrophils — have been explored as a treatment for newborns with severe bacterial infections and critically low white cell counts, a condition called neutropenia that leaves the immune system nearly defenseless. In theory, transfusing functional white cells could bolster the infant’s ability to fight infection until the bone marrow can respond. In practice, granulocyte transfusions are rarely used and remain controversial because the evidence of benefit is limited, the cells are difficult to collect and must be used very quickly, and transfusion reactions are possible.
Platelets Platelets are the tiny blood cell fragments responsible for initiating clot formation when a blood vessel is injured. Premature infants frequently have low platelet counts (thrombocytopenia) due to infection, medications, or conditions affecting the bone marrow’s production capacity. When platelet counts fall to levels associated with a significant risk of spontaneous bleeding — particularly bleeding into the brain — a platelet transfusion can rapidly replenish the supply and restore the blood’s ability to clot.
Plasma Plasma is the liquid component of blood — the fluid in which red cells, white cells, and platelets are suspended — and it contains the proteins responsible for blood clotting (coagulation factors), as well as albumin, antibodies, and many other substances. Fresh frozen plasma (FFP) is administered to newborns who have deficiencies of multiple clotting factors, causing abnormal bleeding or clotting test results. It may also be used to treat certain rare metabolic or immune conditions, or to expand the circulating blood volume in specific clinical situations, though other solutions are more commonly used for volume replacement.
Cryoprecipitate Cryoprecipitate is a concentrated blood product derived from plasma that is particularly rich in fibrinogen and Factor VIII — two proteins that play central roles in the final stages of clot formation. It is used when a baby has severely low fibrinogen levels, which can occur during serious infections (sepsis), liver failure, or a condition called disseminated intravascular coagulation (DIC), in which the clotting system becomes abnormally activated throughout the body, consuming clotting factors faster than they can be replaced. Because it is more concentrated than plasma, cryoprecipitate delivers more fibrinogen in a smaller volume — an important advantage in tiny patients.
Coagulation factors Specific concentrated preparations of individual clotting factors are available for treating rare inherited bleeding disorders. The most relevant in the newborn period is Factor VIII concentrate for hemophilia A and Factor IX concentrate for hemophilia B — X-linked disorders that almost exclusively affect boys and that can first come to clinical attention through unexpected or excessive bleeding in the neonatal period. Using concentrated factor products rather than plasma or cryoprecipitate delivers the specific missing factor in a much smaller volume and with greater precision, reducing the risk of fluid overload and transfusion reactions.
Neonatal Pharmacotherapeutics
Diuretics Diuretics are medications that increase urine production by the kidneys, causing the body to excrete excess fluid. In the NICU, they are most commonly used to manage fluid overload — a situation where too much fluid has accumulated in the body, which can worsen lung function by causing pulmonary edema (fluid in the air sacs) or contribute to a condition called bronchopulmonary dysplasia in premature infants who have required prolonged mechanical ventilation. Furosemide (Lasix) is the most widely used diuretic in neonates, but it must be monitored carefully because it also causes loss of electrolytes such as potassium and calcium, which must be replaced.
Caffeine and Theophylline Xanthine medications — primarily caffeine, and historically theophylline — stimulate the respiratory center in the brain and increase the sensitivity of the breathing drive, making premature infants less prone to apnea (pauses in breathing). Caffeine citrate has become the standard treatment for apnea of prematurity because it is highly effective, safe, has a long and predictable duration of action, and remarkably, has also been shown to reduce rates of bronchopulmonary dysplasia and improve long-term developmental outcomes. It is one of the most evidence-supported medications used in neonatal medicine.
Steroids (corticosteroids) Corticosteroids — most commonly dexamethasone (DecadronTM) or hydrocortisone — have multiple uses in neonatal care. Before birth, betamethasone or dexamethasone given to a mother facing premature delivery dramatically accelerates fetal lung maturation and reduces the severity of respiratory distress syndrome, as well as reducing the risk of brain hemorrhage. After birth, low-dose hydrocortisone may be used to support blood pressure in infants with adrenal insufficiency, while postnatal dexamethasone can reduce lung inflammation in ventilator-dependent infants — though concerns about its effects on brain development have led to much more cautious use than was practiced in earlier decades.
Indomethacin Indomethacin is a medication belonging to the class of drugs called NSAIDs (non-steroidal anti-inflammatory drugs, related to ibuprofen) that, in the context of neonatal care, is used primarily to close a blood vessel called the ductus arteriosus. In fetal life, the ductus arteriosus is a normal connection between the aorta and the pulmonary artery that allows blood to bypass the fluid-filled lungs — but it should close within the first day or two after birth. In premature infants, it often remains open (patent ductus arteriosus, or PDA), causing abnormal blood flow that can worsen lung disease and other complications. Indomethacin (or the related drug ibuprofen) triggers the ductus to close without surgery in many cases.
Antimicrobials Given the vulnerability of newborns — particularly premature infants — to life-threatening bacterial, viral, and fungal infections, antimicrobial medications (antibiotics, antifungals, and antivirals) are among the most frequently prescribed drugs in the NICU. Broad-spectrum antibiotic combinations (typically ampicillin and gentamicin as a first-line regimen) are often started empirically (before culture results are available) when infection is suspected, then narrowed or discontinued based on culture results. Antifungal agents such as fluconazole are used to treat or prevent invasive fungal infections, which are particularly dangerous in extremely premature infants. The antiviral acyclovir is the treatment for herpes simplex virus infection, which can be devastating in newborns.
Heparin Heparin is an anticoagulant — a medication that prevents blood from clotting — and it is used routinely in the NICU in very low doses to keep catheters and IV lines from becoming obstructed by small clots. It can also be used in therapeutic doses to treat or prevent significant blood clots (thromboses) in veins or arteries, when they are a complication of the catheters that are essential for NICU care. Heparin acts quickly and can be rapidly reversed, which makes it valuable in the NICU setting where clinical status can change rapidly. Careful dosing and monitoring are important because both under-treatment (clotting) and over-treatment (bleeding) carry serious risks.
Vasopressors Vasopressors are medications that raise blood pressure and support the circulation in infants whose hearts and blood vessels are not maintaining adequate perfusion of vital organs. Dopamine and dobutamine are the most commonly used agents, working by stimulating the heart to beat more forcefully and/or by causing blood vessels to constrict, raising blood pressure. Epinephrine (adrenaline) is used in more severe situations, including cardiac arrest. Hydrocortisone is sometimes added when vasopressors alone are insufficient, as adrenal insufficiency can contribute to refractory low blood pressure (hypotension) in sick premature infants.
Sedatives and analgesics Premature and critically ill newborns experience pain and stress from many sources — including endotracheal tubes, needle sticks, surgical procedures, and the general discomfort of illness — and managing this pain humanely and effectively is an ethical imperative as well as a clinical priority, since unrelieved pain and stress have measurable adverse effects on the developing brain. Opioid analgesics such as morphine and fentanyl are used for moderate to severe pain and during ventilation. Non-opioid analgesics such as acetaminophen (TylenolTM) provide milder analgesia. Sedatives such as midazolam (VersedTM, a benzodiazepine) may be used during procedures, though their routine use in ventilated premature infants has been tempered by concerns about neurological effects.
Last Updated on 04/06/26