Nosocomial infections on the rise in NICUs

Zafar, N., et al. Improving survival of vulnerable infants increases neonatal intensive care unit nosocomial infection rate. Archives of Pediatrics and Adolescent Medicine, 155(10): 1098-1104. October 2001.

Nosocomial infections among preterm infants are on the rise, possibly because technology now allows very low birth weight infants-who are at great risk for infection-to survive.

This retrospective chart review studied 1,085 preterm infants weighing less than 1,500 grams who were born between January 1991 and December 1997 at a St. Louis, Mo., hospital. The group was subdivided into those born between 1991-95 and those born in 1996 and 1997. Data were collected on the babies' birth weight, gestational age, length of stay in the unit, whether they lived or died, number of infections, age at infection, microorganisms suspected or verified, use of corticosteroids, use of mechanical ventilation, and use of long-term vascular access.

Nosocomial infections were reported in the bloodstream (53%), respiratory tract (27%), urinary tract (14%), GI tract (4%), and cerebrospinal fluid (1%). There was no difference between the groups' infection rates based on their demographic variables, except for birth weight-the smaller the infant, the more likely he or she had an infection. Infants who received postnatal corticosteroid therapy were more likely to get an infection, but were less likely to die from it. Although more infants in the later-born group required mechanical ventilation or vascular access, no difference was found in their infection rates over time, suggesting that problems with ventilator and catheter management practices did not contribute to the increase in infections.

Researchers concluded that the increase in infection rates was probably due to individual factors relating to either the mother or the baby.

Janet T. Ihlenfeld RN PhD

Professor of Nursing, D'Youville College, Buffalo, N.Y.

Extra vitamins may help preterm infants

Lucas A, et al. Randomized trial of nutrient-enriched formula versus standard formula for postdischarge preterm infants. Pediatrics, 108(3):703-11. September 2001.

Preterm infants often remain smaller than full-term infants months after they are discharged home. This study investigated whether the use of a nutritionally enhanced formula in preterm infants increased their weight and length after discharge.

The study followed 206 preterm infants with birth weights less than 1,750 grams who were born in 5 different neonatal units in England between 1993 and 1995. The infants were randomly assigned to receive either the nutritionally enhanced formula or a standard formula for preterm infants.

The nutritionally enhanced formula had higher levels of calories, protein, carbohydrates, fats, minerals, and vitamins. Both groups were followed for growth and development variables for 18 months post-discharge. A third group of 65 breastfed preterm infants was also recruited to serve as a reference group.

At 9 months, the infants given the special formula were heavier and longer than those who had received the regular formula. This difference persisted to 18 months but was smaller than at the 9 month measurement. Head circumference measurements between the groups did not differ. Surprisingly, the breastfed infants were consistently smaller than either of the formula-fed groups.

Developmentally, there was no difference between the groups in motor, language, and social skills at 9 and 18 months corrected age.

Although the researchers believe that all preterm infants should receive nutritionally enhanced formula, based on this study's results, other studies are needed before nutritional guidelines for preterm infants are drastically changed.

Janet T. Ihlenfeld RN PhD

Professor of Nursing, D'Youville College, Buffalo, N.Y.