Standardization of urinary tract infection diagnosis in the neonatal ICU: Experience at a tertiary care center.

BACKGROUND: Urinary tract infections (UTIs) and antibiotic overexposure are common neonatal problems. Recently, evidence has emerged that a standardized approach to neonatal UTI can reduce unnecessary diagnosis without complications. This quality improvement project aimed to achieve those goals in our neonatal intensive care unit (NICU). METHODS: A UTI diagnosis guideline was adapted from the literature with the goal of maximizing the proportion of diagnosed UTIs that conform to accepted diagnostic criteria: >10,000 CFU/mL of one organism with pyuria, or >50,000 CFU/mL of one organism regardless of pyuria. The guideline was implemented in a level III NICU. Adherence, results, and complications were monitored for 12 months. RESULTS: Guideline adherence after implementation was favorable, as evidenced by increased adoption of urinalysis with microscopy. There was a non-significant increase in diagnostic adherence to criteria, 87% to 93%, and non-significant decrease in the rate of UTI diagnosis, 39% to 36%. Complications were not significantly changed. Most UTIs were due to gram-negative rods, especially E. coli; Enterococcus was a common contaminant. CONCLUSIONS: A guideline for diagnosing UTIs can safely increase uniformity. In contrast to previously published results, no significant changes were seen in the rate of UTI or the proportion of diagnoses conforming to the criteria for UTI. It is likely that guideline effects depend on the established practices of NICU providers. Additionally, a consistent pattern was seen in which organisms were more likely to be judged the source of true UTIs or contaminated cultures, meriting further study.

Optimizing antibiotic use for early onset sepsis: A tertiary NICU experience.

BACKGROUND: Neonatal antibiotic use is associated with a greater risk of nosocomial infection, necrotizing enterocolitis, and mortality. It can induce drug-resistant pathogens that contribute to increased neonatal morbidity/mortality, healthcare costs, and length of stay. Prior to the antibiotic stewardship program, decisions to obtain blood cultures and empiric antibiotics for possible Early-onset Sepsis (EOS) in late preterm and term infants upon NICU admission were provider-dependent rather than algorithm-based. We aimed to decrease empiric antibiotic prescription from 70% to 56% (20% decrease) in infants ≥34 weeks gestation admitted to the NICU. METHODS: The stewardship initiative comprised the following practice changes: (1) use of the Neonatal Sepsis Risk Calculator (SRC); and (2) a 36-hour time-out for prescribed empiric antibiotics. Data was retrospectively collected and analyzed for inborn infants pre-intervention (January 2015-December 2015; n = 263) and post-intervention (August 2016-September 2017; n = 279). Data regarding compliance with the new antibiotic guideline were collected and disseminated to the team every week. Overlap between CDC guidelines and calculator recommendations were studied. RESULTS: Pre-and post-intervention outcomes were analyzed using chi-square tests. There was a significant post-intervention reduction in the rate of both antibiotic prescriptions (29.4% decline; 70.3% vs. 49.6%; p < 0.001) and sepsis evaluations (24.3% decline; 90.9% vs. 68.8%; p < 0.001). No difference (p = 0.271) in culture-positive EOS cases was observed. There was 92% overlap in blood culture recommendations and 95% overlap between antibiotic recommendations when current CDC guidelines were compared to the SRC. CONCLUSION: A significant reduction in antibiotic use and sepsis evaluations was achieved for late preterm and term infants upon NICU admission. No clinical deterioration occurred in post-intervention infants who did not receive antibiotics. There is significant overlap between CDC guidelines and SRC recommendations.

The effects of human milk fortification on nutrients and milk properties.

OBJECTIVE: To investigate the effects of fortification and storage on nutrients and properties of various human milk (HM) types. STUDY DESIGN: Mother's own milk (MOM) and pasteurized donor human milk (DHM; n=118) were analyzed pre- and post fortification with Enfamil and Similac human milk fortifier (EHMF and SHMF) before and after 24 h of refrigerated storage. RESULTS: Milk fortified with SHMF had significantly greater osmolality, pH and lipase activity than EHMF. Changes in protein, pH and osmolality following refrigerated storage differed between fortifiers. When milk type was factored into the analysis, protein and lipase activity changes in fresh MOM differed significantly from DHM and frozen MOM. Analysis of UNF HM found higher protein levels in preterm vs term samples and in MOM vs DHM. CONCLUSION: Nutrient composition of HM varies significantly by milk type. Although fortifiers enhance select nutrients, each has the potential to affect HM properties in a unique way and these affects may vary by milk type.

Selective Endothelin-B Receptor Stimulation Increases Vascular Endothelial Growth Factor in the Rat Brain during Postnatal Development.

Endothelin, vascular endothelial growth factor and nerve growth factor play important roles in development of the central nervous system. ET(B) receptors have been shown to promote neurovascular remodeling in the adult ischemic brain through an increase in VEGF and NGF. It is possible that ET(B) receptors may be involved in postnatal development of the brain through VEGF and NGF. In the present study, the brains of male rat pups on postnatal days 1, 7, 14 and 28 were analyzed for expression of ET(B) receptors, VEGF and NGF. In order to determine the effect of ET(B) receptor stimulation, a separate group of pups were administered saline or ET(B) receptor agonist, IRL-1620, on day 21, and their brains were analyzed on day 28. The intensity of ET(B) receptor and VEGF staining in the vasculature as well as the number of blood vessels of normal pups increased with age and was significantly higher on postnatal day 14 compared to day 1 and day 7. In contrast, both ET(B) and NGF staining intensity in the cortex and subventricular zones decreased (P<0.01) at postnatal day 14 compared to earlier time points. Stimulation of ET(B) receptors resulted in a significant increase in VEGF and ET(B) intensity both in the vasculature and the brain (P<0.05), however, IRL-1620 did not produce any change in NGF expression. Results indicate that ET(B) receptors appear to play a role in the development of the CNS and selective stimulation of ET(B) receptors enhances VEGF but not NGF in the postnatal rat brain.

Emission of volatile organic compounds from medical equipment inside neonatal incubators.

OBJECTIVE: To determine emission of volatile organic compounds (VOCs) from plastic medical equipment within an incubator. STUDY DESIGN: Air samples from incubators before and after adding medical equipment were analyzed using EPA TO-15 methodology. Headspace analysis was used to identify VOC emissions from each medical equipment item. Air changes per hour (ACH) of each incubator were determined and used to calculate the emission rate of identified VOCs. RESULTS: Cyclohexanone was identified in all incubator air samples. At 28 °C, the mean concentration before and after adding medical equipment items was 2.1 ± 0.6 and 57.2 ± 14.9 µg m(-3),respectively (P<0.01). Concentrations increased to a mean of 83.8 ± 23.8 µg m(-)(3) (P<0.01) at 37(o)C and 93.0 ± 45.1 µg m(-)(3) (P=0.39) after adding 50% humidity. Intravenous tubing contributed 89% of cyclohexanone emissions. ACH were determined with access doors closed and open with means of 11.5 ± 1.7 and 44.1 ± 6.7 h(-1), respectively. Cyclohexanone emission rate increased from a mean of 102.2 µg h(-1) at 28(°C to 148.8 µg h(-1) (P<0.01) at 37 °C. CONCLUSION: Cyclohexanone was quantified in all incubator air samples containing plastic medical equipment. The concentration of cyclohexanone within the incubator was inversely related to ACH in the closed mode. The cyclohexanone concentration as well as the emission rate increased with higher temperature.

Airborne concentrations of volatile organic compounds in neonatal incubators.

OBJECTIVE: To identify and quantify airborne volatile organic compounds (VOCs) inside neonatal incubators during various modes of operation within the neonatal intensive care unit (NICU) environment. STUDY DESIGN: Air samples were taken from 10 unoccupied incubators in four operational settings along with ambient air samples using air sampling canisters. The samples were analyzed following EPA TO-15 using a Tekmar AutoCan interfaced to Agilent 6890 Gas Chromatograph with a 5973 Mass Spectrometer calibrated for 60 EPA TO-15 method target compounds. Non-target compounds were tentatively identified using mass spectral interpretation and with a mass spectral library created by National Institute for Standards and Technology. RESULT: Two non-target compounds, 2-heptanone and n-butyl acetate, were found at elevated concentrations inside the incubators compared with ambient room air samples. Increase in temperature and addition of humidity produced further increased concentrations of these compounds. Their identities were verified by mass spectra and relative retention times using authentic standards. They were quantified using vinyl acetate and 2-hexanone as surrogate standards. CONCLUSION: The emission pattern of these two compounds and background measurements indicate that they originate inside the incubator. There is evidence that exposure to some VOCs may adversely impact the fetal and developing infants' health. Currently, as there is no definitive information available on the effects of acute or chronic low-level exposure to these compounds in neonates, future studies evaluating the health effects of neonatal exposure to these VOCs are needed.