Risk factors for nosocomial infection in a high-risk nursery

Trends in the incidence and associated factors of late-onset sepsis associated with improved survival in extremely preterm infants born at 23-26 weeks' gestation: a retrospective study

Background

To investigate the trends in the incidence and associated factors of late-onset sepsis (LOS) associated with improved survival in extremely preterm infants.

Methods

Medical records of 364 infants who were born at 23–26 weeks’ gestation from 2000 to 2005 (period I, n = 124) and from 2006 to 2011 (period II, n = 240) were retrospectively reviewed. The infants were stratified into subgroups of 23–24 and 25–26 weeks’ gestation within each period, and survival, LOS rate, and clinical characteristics were analyzed. Multivariate logistic regression analyses were completed to identify the clinical factors associated with LOS.

Results

The survival rate of 75.8% during period I significantly improved to 85.4% during period II, especially in infants at 23–24 weeks’ gestation (55.1% vs. 78.1%, respectively). The LOS rate of 33.1% during period I significantly reduced to 15.8% during period II, especially in infants at 25–26 weeks’ gestation (32.0% vs. 8.9%, respectively). The LOS rate per 1000 hospital days of 4.0 during period I significantly reduced to 1.8 during period II. Candida presence reduced from 21.3% during period I to 4.7% during period II. In multivariate analyses, during period I, prolonged intubation, especially in infants at 25–26 weeks’ gestation, and necrotizing enterocolitis, especially in infants at 23–24 weeks’ gestation, were significantly associated with LOS.

Conclusions

Improved survival of infants at 23–24 weeks’ gestation was associated with a simultaneous reduction of LOS incidence in infants at 25–26 weeks’ gestation. Less-invasive assisted ventilation may be one of the details of improved perinatal and neonatal care that has contributed to lowering risk of infection or death among periviable infants.

Electronic supplementary material

The online version of this article (10.1186/s12887-018-1130-y) contains supplementary material, which is available to authorized users.

Risk factors for bronchopulmonary dysplasia in neonates born at ≤ 1500 g (1999-2009)

BACKGROUND

Advances in perinatal care have improved the survival rate for very low-birthweight (VLBW) infants in China. The incidence of bronchopulmonary dysplasia (BPD), however, has not been reduced. The objective of the present study was to identify the perinatal risk factors for BPD in neonates born at ≤ 1500 g.

METHODS

A retrospective analysis of data for neonates born at ≤ 1500 g between 1999 and 2009 in the neonatal intensive care unit (NICU) of Second Affiliated Hospital of Sun Yat-Sen University, Guangzhou city, China, was carried out.

RESULTS

Out of a total of 11,506 live births, 3538 infants were admitted to level II nursery and NICU (level III nursery). Among 149 preterm infants born at ≤ 1500 g, 77.8% survived until day 28, and the incidence of BPD was 48.3%. Logistic regression analysis showed that gestational age (GA) ≤ 30 weeks (odds ratio [OR], 9.507; 95% confidence intervals [95%CI]: 2.604-34.707), maternal chorioamnionitis (OR, 41.987; 95%CI: 6.048-291.492), ventilation-associated pneumonia (OR, 11.600; 95%CI: 2.847-47.268), and more than three blood transfusions (OR, 10.214; 95%CI: 2.191-47.623) were associated with the development of BPD.

CONCLUSION

Clinical evidence has been provided for possibly significant risk factors associated with BPD in neonates born at ≤ 1500 g, which can provide useful information for further research to improve survival of VLBW infants and decrease the incidence of BPD.

Determinants of nosocomial infection in 6 neonatal intensive care units: an Italian multicenter prospective cohort study

BACKGROUND

Nosocomial infections are still a major cause of morbidity and mortality among neonates admitted to neonatal intensive care units (NICUs).

OBJECTIVE

To describe the epidemiology of nosocomial infections in NICUs and to assess the risk of nosocomial infection related to the therapeutic procedures performed and to the clinical characteristics of the neonates at birth and at admission to the NICU, taking into account the time between the exposure and the onset of infection.

DESIGN

A multicenter, prospective cohort study.

PATIENTS AND SETTING

A total of 1,692 neonates admitted to 6 NICUs in Italy were observed and monitored for the development of nosocomial infection during their hospital stay.

METHODS

Data were collected on the clinical characteristics of the neonates admitted to the NICUs, their therapeutic interventions and treatments, their infections, and their mortality rate. The cumulative probability of having at least 1 infection and the cumulative probability of having at least 1 infection or dying were estimated. The hazard ratio (HR) for the first infection and the HR for the first infection or death were also estimated.

RESULTS

A total of 255 episodes of nosocomial infection were diagnosed in 217 neonates, yielding an incidence density of 6.9 episodes per 1,000 patient-days. The risk factors related to nosocomial infection in very-low-birth-weight neonates were receipt of continuous positive airway pressure (HR, 3.8 [95% confidence interval {CI}, 1.7-8.1]), a Clinical Risk Index for Babies score of 4 or greater (HR, 2.2 [95% CI, 1.4-3.4]), and a gestational age of less than 28 weeks (HR, 2.1 [95% CI, 1.2-3.8]). Among heavier neonates, the risk factors for nosocomial infection were receipt of parenteral nutrition (HR, 8.1 [95% CI, 3.2-20.5]) and presence of malformations (HR, 2.3 [95% CI, 1.5-3.5]).

CONCLUSIONS

Patterns of risk factors for nosocomial infection differ between very-low-birth-weight neonates and heavier neonates. Therapeutic procedures appear to be strong determinants of nosocomial infection in both groups of neonates, after controlling for clinical characteristics.

Evidence-based algorithms for diagnosing and treating ventilator-associated pneumonia

BACKGROUND

Ventilator-associated pneumonia (VAP) is widely recognized as a serious and common complication associated with high morbidity and high costs. Given the complexity of caring for heterogeneous populations in the intensive care unit (ICU), however, there is still uncertainty regarding how to diagnose and manage VAP.

OBJECTIVE

We recently conducted a national collaborative aimed at reducing health care-associated infections in ICUs of hospitals operated by the Hospital Corporation of America (HCA). As part of this collaborative, we developed algorithms for diagnosing and treating VAP in mechanically ventilated patients. In the current article, we (1) review the current evidence for diagnosing VAP, (2) describe our approach for developing these algorithms, and (3) illustrate the utility of the diagnostic algorithms using clinical teaching cases.

DESIGN

This was a descriptive study, using data from a national collaborative focused on reducing VAP and catheter-related bloodstream infections.

SETTING

The setting of the study was 110 ICUs at 61 HCA hospitals.

INTERVENTION

None.

MEASUREMENTS AND RESULTS

We assembled an interdisciplinary team that included infectious disease specialists, intensivists, hospitalists, statisticians, critical care nurses, and pharmacists. After reviewing published studies and the Centers for Disease Control and Prevention VAP guidelines, the team iteratively discussed the evidence, achieved consensus, and ultimately developed these practical algorithms. The diagnostic algorithms address infant, pediatric, immunocompromised, and adult ICU patients.

CONCLUSIONS

We present practical algorithms for diagnosing and managing VAP in mechanically ventilated patients. These algorithms may provide evidence-based real-time guidance to clinicians seeking a standardized approach to diagnosing and managing this challenging problem.

[Incidence of nosocomial infections at a neonatal intensive care unit: a six-year surveillance study]

INTRODUCTION

Nosocomial infection is a frequent complication in neonatal intensive care units (NICUs) attending patients who require lengthy hospitalization and frequent invasive techniques.

PATIENTS AND METHODS

This study is part of a prospective surveillance program for nosocomial infection in Spain. All patients admitted to NICUs between June 1999 and March 2005 were observed. CDC criteria were used as the standard definition for nosocomial infection.

RESULTS

A total of 1236 neonates (58% male) were admitted during the surveillance period, involving 19,420 days in the NICU. The average birth weight was 1947.6 +/- 1009.5 g and average gestational age was 32.9 +/- 5.4 weeks. The most frequent associated pathology was respiratory distress (23.06%). A total of 316 nosocomial infections were diagnosed in 226 neonates, 76.7% affecting premature neonates (< 1500 g). The most frequent location was bacteremia (56.3%), and there was a predominance of coagulase-negative staphylococci (46.05%). Gram-negative microorganisms were isolated in 32.1% of the cases (Escherichia coli and Pseudomonas aeruginosa were the most frequent pathogens). Overall incidence of nosocomial infection was 25.6%. Overall mortality was 6.6%, with higher mortality in the group with nosocomial infections (8.7%).

CONCLUSIONS

Nosocomial infection rates are acceptable, with a typical epidemiological pattern for these units. Presence of a central catheter increased the risk. A program to promote proper hand washing should be considered. We do not recommend a continuing surveillance strategy in these units.

The efficacy of clinical strategies to reduce nosocomial sepsis in extremely low birth weight infants

The aim of this study was to evaluate the efficacy of clinical strategies to reduce nosocomial sepsis (NS) in extremely low birth weight infants (ELBWI) less than 1,000 g. Data from the period before (P1, 1995-2000) and after (P2, 2001-2002) implementation of the strategies were collected and analyzed. The intervention strategies included restriction of antibiotic therapy, less use of invasive procedures such as umbilical vessel catheterization and endotracheal intubation, establishment of guidelines for hand-washing, infant handling, and central intravascular line management. NS was defined as positive blood cultures in symptomatic patients after the third day of life with the use of antibiotics for more than 5 days. Although the gestational age (GA) and birth weight (BW) were significantly lower in P2 (GA 26.7 +/-2.1 wk; BW 796 +/-130 g) compared to P1 (GA 27.2 +/-1.6 wk; BW 857 +/-121 g), the incidence of NS decreased significantly from 70% (69/99) in P1 to 17% (24/71) in P2 with the implementation of the intervention strategies. The coagulase negative Staphylococcus infection was also significantly reduced from 34% in P1 to 11% in P2. The implementation of the clinical strategies was quite effective in reducing the incidence of NS in ELBWI.

Ventilator-associated pneumonia in extremely preterm neonates in a neonatal intensive care unit: characteristics, risk factors, and outcomes

OBJECTIVE

To determine the rates, characteristics, risk factors, and outcomes of ventilator-associated pneumonia (VAP) in extremely preterm neonates in a neonatal intensive care unit (NICU).

METHODS

A prospective cohort study was conducted at the St Louis Children's Hospital on all patients who had birth weight <or=2000 g and were admitted to the NICU for >or=48 hours from October 2000 to July 2001. Extremely preterm neonates were defined as neonates with estimated gestational age (EGA) <28 weeks. The primary outcome was the development of VAP. Secondary outcomes were death and NICU length of stay (LOS). Multiple logistic regression was performed to determine independent predictors for VAP and mortality.

RESULTS

A total of 229 patients were enrolled. Sixty-seven (29%) had EGA <28 weeks. Nineteen episodes of VAP occurred in 19 (28.3%) of 67 mechanically ventilated patients. VAP rates were 6.5 per 1000 ventilator days for patients with EGA <28 weeks and 4 per 1000 ventilator days for EGA >or=28 weeks. By multivariate analysis, bloodstream infection before VAP (adjusted odds ratio: 3.5; 95% confidence interval [CI]: 1.2-10.8) was an independent risk factor for VAP after adjustment for the duration of endotracheal intubation. Ventilator-associated pneumonia (adjusted odds ratio: 3.4; 95% CI: 1.2-12.3) was an independent predictor of mortality. A strong association between VAP and mortality was observed in neonates who stayed in the NICU >30 days (relative risk: 8.0; 95% CI: 1.9-35.0). Patients with VAP also had prolonged NICU LOS (median: 138 vs 82 days).

CONCLUSIONS

VAP occurred at high rates in extremely preterm neonates and was associated with increased mortality. Additional studies are needed to develop interventions to prevent VAP in NICU patients.

Intercenter variability and time of onset: two crucial issues in the analysis of risk factors for nosocomial sepsis

BACKGROUND

Nosocomial sepsis is one of the most important causes of morbidity and mortality in neonatal intensive care units (NICUs).

OBJECTIVE

To assess the impact of clinical conditions, exposure to invasive procedures and NICU characteristics on late (3 to 10 days) nosocomial sepsis (LNS) and very late (>10 days) nosocomial sepsis (VLNS) and to describe the variability among NICUs.

METHODS

Multicenter prospective study in 21 NICUs including all newborns admitted in a 18-month period, weighing </=1750 g at birth or suffering major illness. Infections were diagnosed according to Centers for Disease Control and Prevention clinical criteria. Kaplan-Meyer curves and Cox models were used to identify major determinants of LNS and VLNS and its intercenter variability.

RESULTS

Of the 2160 neonates admitted to the 21 NICUs, 196 neonates developed a LNS, and 137 developed a VLNS. Some selected neonatal characteristics were independently associated with LNS, but not with VLNS (i.e. respiratory distress syndrome or patent ductus arteriosus), and the opposite was true for other conditions (i.e., necrotizing enterocolitis or high maximum base excess at admission). Exposure to mechanical ventilation and central venous catheter increased the risk of LNS and VLNS. Being admitted to specific NICUs independently increased the risk of both LNS and VLNS.

CONCLUSIONS

To analyze risk factors correctly for hospital-acquired infections in multicenter studies in NICUs, Cox modeling and stratification by time of infection onset should be used, and the existing intercenter variability should be taken into account.

Prevention of nosocomial infections in the neonatal intensive care unit

Nosocomial infections are responsible for significant morbidity and late mortality among neonatal intensive care unit patients. The number of neonatal patients at risk for acquiring nosocomial infections is increasing because of the improved survival of very low birthweight infants and their need for invasive monitoring and supportive care. Effective strategies to prevent nosocomial infection must include continuous monitoring and surveillance of infection rates and distribution of pathogens; strategic nursery design and staffing; emphasis on handwashing compliance; minimizing central venous catheter use and contamination, and prudent use of antimicrobial agents. Educational programs and feedback to nursery personnel improve compliance with infection control programs.

Nosocomial infections in the neonatal intensive care unit

Nosocomial infections are significant causes of morbidity and mortality in patients who require newborn intensive care. The most common bacterial pathogens are Gram-positive bacteria, including Staphylococcus epidermidis, Staphylococcus aureus, and Enterococcus species. Gram-negative enteric bacilli and Gram-negative environmental bacteria are involved in outbreaks and occasional cases of nosocomial infection. The incidence of fungal infection has increased over the past 10 years; fungemia is the most commonly recognized infection. Surveillance for nosocomial infection is essential to identify outbreaks and detect unsuspected reservoirs of pathogens. A variety of molecular techniques can be used to determine the genetic relatedness of pathogens. Prevention of infection requires the identification of contaminated equipment, education regarding infection control methods including hand washing, and the judicious use of antimicrobial agents.