Linda J. Reubens

Prevention of central venous catheter-related coagulase-negative staphylococcal sepsis in neonates

A randomized, double-blind, controlled trial was conducted to determine whether vancomycin added to parenteral alimentation solution given via a central venous catheter would decrease the incidence of catheter-related coagulase-negative staphylococcal sepsis. Seventy infants with a central venous catheter (CVC) in place were randomly selected to receive total parenteral nutrition--either the standard solution or a solution containing 25 micrograms of vancomycin per milliliter. Catheter-related sepsis was defined as the isolation of the same bacterial species from specimens of both peripheral and CVC blood with the concentration of bacteria at least tenfold greater in the specimen obtained from the CVC. Specimens from the CVCs were cultured on removal of the catheters to determine colonization. The colonization of catheters by coagulase-negative staphylococci was reduced from 40% to 22% (p = 0.03) in the vancomycin group; catheter-related sepsis was reduced from 15% to no cases (p = 0.004). Fewer infants required CVC reinsertion in the vancomycin-treated group (p = 0.02), who also regained birth weight earlier (13.4 vs 17.1 days (p = 0.014)). Adverse effects of vancomycin infusion were not observed. We conclude that vancomycin added to the solution used for total parenteral nutrition effectively reduces catheter-related sepsis in the neonatal intensive care unit and offers other potential benefits such as the need for fewer catheters and earlier weight gain. However, we do not recommend widespread implementation of this technique until there are data regarding the emergence of vancomycin-resistant organisms.

A Randomized Trial Comparing Long-term and Short-term Use of Umbilical Venous Catheters in Premature Infants With Birth Weights of Less Than 1251 Grams

BACKGROUND. Umbilical vein and percutaneous central venous catheters are often used in preterm infants, but they can lead to complications, including infection. OBJECTIVE. We hypothesized that long-term umbilical vein catheter use would result in fewer infections than short-term umbilical vein catheter use followed by percutaneous central venous catheter placement. DESIGN/METHODS. Infants ≤1250 g with umbilical vein catheters placed at admission were randomly assigned to a long-term (umbilical vein catheter up to 28 days) or short-term (umbilical vein catheter for 7–10 days followed by percutaneous central venous catheter) group. Catheter infection was defined as symptoms and ≥1 positive blood culture for definite pathogens or >1 positive culture for other organisms, with a catheter in place. Clinically significant echocardiogram findings were defined as thrombi threatening vascular occlusion, crossing/blocking heart valves, or otherwise felt to be significant by the cardiologist. The primary outcome was time from birth to catheter infection, analyzed by the log-rank test. RESULTS. There were 106 subjects in the short-term group and 104 in the long-term group with birth weights of 915 ± 198 and 931 ± 193 g and gestational ages of 27.8 ± 2.0 and 27.7 ± 2.2 weeks, respectively. The distribution of time to catheter infection did not differ between the groups. The overall incidence of catheter infection was 13% in the short-term group and 20% in the long-term group. Median age at catheter infection was 11.5 days in the short-term group and 14 days in the long-term group. There were 7.4 infections per 1000 catheter-days in the short-term group and 11.5 per 1000 in the long-term group. Seven infections in the short-term group were in umbilical vein catheters, and 18 infections in the long-term group were in umbilical vein catheter. Echocardiograms detected 4 infants in the short-term group and 7 infants in the long-term group with significant thrombosis. All significant thrombi were at the site of the umbilical vein catheter tip. No thrombus caused hemodynamic compromise, no child had clinical symptoms of thrombosis, and none required therapy. Of the 45 small-for-gestational-age infants in the study, 9 developed thrombi (short-term group, 4; long-term group, 5). The incidence of thrombi was higher in the small-for-gestational-age group (20%) versus other study subjects (9%). There were no differences in time to full feedings or to regain birth weight or in the incidence of necrotizing enterocolitis or death. CONCLUSIONS. Infection and complication rates were similar between infants managed with an umbilical vein catheter in place for up to 28 days compared with infants managed with an umbilical vein catheter replaced by a percutaneous central venous catheter after 7 to 10 days. Umbilical vein catheter durations beyond the current Centers for Disease Control and Prevention–recommended limit of 14 days may be reasonable.

Frequency of Elevations in Markers of Cardiomyocyte Damage in Otherwise Healthy Newborns

Myocardial damage in infancy is a risk factor for eventual cardiac disease. Given that myocardial stress is greatest during the perinatal period and that the neonatal period is when most pediatric heart failure occurs, the aim of this study was to determine whether even otherwise healthy neonates might have subclinical myocardial damage and, if so, what characteristics might identify them. Umbilical cord and neonatal serum samples from 32 normal neonates were assayed for biomarkers of myocardial injury. No neonate had clinical evidence of cardiac or other abnormalities. Serum cardiac troponin T was elevated in 19 of 25 cords (76%) and in 16 of 17 neonates (94%); levels indicating myocardial infarction (> or =0.2 ng/ml) were found in 2 patients (1 umbilical cord and 1 neonatal sample). Creatine kinase-MB was elevated in 6 of 16 cords (38%) and in 8 of 15 neonates (53%). Cardiac troponin I was elevated in 11% and 17% of samples, myoglobin in 4% and 17%, and high-sensitivity C-reactive protein in 9% and 40%. Measures of myocardial injury were associated with longer hospitalization (r = 0.50, p = 0.04), non-Caucasian race (p = 0.012), lower birth weights (p = 0.014), positive maternal cervical cultures (r = 0.41, p = 0.046), and elevated high-sensitivity C-reactive protein (r = 0.66, p = 0.005). In conclusion, clinically occult myocardial injury appears to occur in some healthy newborns, although whether it is pathologic or not remains to be determined.