Prevention of gram-positive sepsis in neonates weighing less than 1500 grams

Vancomycin Use in Children and Neonates across Three Decades: A Bibliometric Analysis of the Top-Cited Articles

Vancomycin is frequently prescribed in pediatrics, especially in intensive care unit settings, to treat Gram-positive bacterial infections. This work aims to collect the top-cited articles of pediatric and infectious diseases areas to gather the current evidence and gaps of knowledge on the use of vancomycin in these populations. The most relevant journals reported in the "pediatrics" and "infectious diseases" categories of the 2019 edition of Journal Citation Reports were browsed. Articles with more than 30 citations and published over the last three decades were collected. A bibliometric analysis was performed and 115 articles were retrieved. They were published in 21 journals, with a median impact factor of 4.6 (IQR 2.9-5.4). Sixty-eight of them (59.1%) belonged to "infectious diseases" journals. The most relevant topic was "bloodstream/complicated/invasive infections", followed by "antibiotic resistance/MRSA treatment". As for population distribution, 27 articles were on children only and 27 on neonates, most of which were from intensive care unit (ICU) settings. The current literature mainly deals with vancomycin as a treatment for severe infections and antibiotic resistance, especially in neonatal ICU settings. Lately, attention to new dosing strategies in the neonatal and pediatric population has become a sensible topic.

Guideline for Prevention of Intravascular-Device–Related Infections

The “Guideline for Prevention of Intravascular Device-Related Infections” is designed to reduce the incidence of intravascular device-related infections by providing an over view of the evidence for recommendations considered prudent by consensus of Hospital Infection Control Practices Advisor y Committee (HICPAC) members. This two-part document updates and replaces the previously published Centers for Disease Control's (CDC) Guideline for Intravascular Infections (Am J Infect Control1983;11:183-199). Part I, “Intravascular Device-Related Infections: An Over view” discusses many of the issues and controversies in intravascular-device use and maintenance. These issues include definitions and diagnosis of catheter-related infection, appropriate barrier precautions during catheter insertion, inter vals for replacement of catheters, intravenous (IV) fluids and administration sets, catheter-site care, the role of specialized IV personnel, and the use of prophylactic antimi-crobials, flush solutions, and anticoagulants. Part II, “Recommendations for Prevention of Intravascular Device-Related Infections” provides consensus recommendations of the HICPAC for the prevention and control of intravascular device-related infections. A working draft of this document also was reviewed by experts in hospital infection control, internal medicine, pediatrics, and intravenous therapy. However, all recommendations contained in the guideline may not reflect the opinion of all reviewers.

Effect of Nurse Staffing and Antimicrobial-Impregnated Central Venous Catheters on the Risk for Bloodstream Infections in Intensive Care Units

Background:

Defining risk factors for central venous catheter (CVC)-associated bloodstream infections (BSIs) is critical to establishing prevention measures, especially for factors such as nurse staffing and antimicrobial-impregnated CVCs.

Methods:

We prospectively monitored CVCs, nurse staffing, and patient-related variables for CVC-associated BSIs among adults admitted to eight ICUs during 2 years.

Results:

A total of 240 CVC-associated BSIs (2.8%) were identified among 4,535 patients, representing 8,593 CVCs. Antimicrobial-impregnated CVCs reduced the risk for CVC-associated BSI only among patients whose CVC was used to administer total parenteral nutrition (TPN, 2.6 CVC-associated BSIs per 1,000 CVC-days vs no TPN, 7.5 CVC-associated BSIs per 1,000 CVC-days;P= .006). Among patients not receiving TPN, there was an increase in the risk of CVC-associated BSI in patients cared for by “float” nurses for more than 60% of the duration of the CVC. In multivariable analysis, risk factors for CVC-associated BSIs were the use of TPN in non-antimicrobial-impregnated CVCs (P= .0001), patient cared for by a float nurse for more than 60% of CVC-days (P= .0019), no antibiotics administered to the patient within 48 hours of insertion (P= .0001), and patient unarousable for 70% or more of the duration of the CVC (P= .0001). Peripherally inserted central catheters (PICCs) were associated with a lower risk for CVC-associated BSI (P= .0001).

Conclusions:

Antimicrobial-impregnated CVCs reduced the risk of CVC-associated BSI by 66% in patients receiving TPN. Limiting the use of float nurses for ICU patients with CVCs and the use of PICCs may also reduce the risk of CVC-associated BSI.

Duration of vancomycin treatment for coagulase-negative Staphylococcus sepsis in very low birth weight infants

AIM

Vancomycin is widely used to treat late onset coagulase-negative Staphylococcus (CoNS) sepsis in very low birth weight (VLBW) infants. Although vancomycin is associated with a risk of toxicity and bacterial resistance, the appropriate duration of use has not been established. This study sought to investigate the association between the duration of vancomycin therapy and clinical outcome in VLBW infants with CoNS sepsis.

METHODS

The files of all VLBW infants treated for CoNS sepsis at a tertiary paediatric medical centre from 1995-2003 were reviewed for clinical data, laboratory variables and outcome. Only patients with two positive diagnostic blood cultures were included. The findings were analyzed by duration of vancomycin treatment after the last positive blood culture.

RESULTS

The study cohort included 126 infants, 48 treated for 5 days, 32 for 6-7 days, 31 for 8-10 days and 15 for >10 days. There were no differences among the groups in perinatal characteristics, central catheter dwell time, laboratory data including haematologic, renal and liver function tests, or rate of complications of prematurity. Five infants were diagnosed with infective endocarditis or aortic thrombi and were treated for >10 days. CoNS sepsis recurred in two infants (1.6%). No toxicity of vancomycin treatment was observed.

CONCLUSIONS

In VLBW infants with uncomplicated CoNS sepsis, treatment with vancomycin for 5 days after the last positive blood culture appears to be associated with a satisfactory outcome and no adverse effects. A well-controlled prospective multicentre study is needed to confirm these findings.

Bench-to-bedside review: Challenges of diagnosis, care and prevention of central catheter-related bloodstream infections in children

Central venous catheters (CVCs) are indispensable in modern pediatric medicine. CVCs provide secure vascular access, but are associated with a risk of severe complications, in particular bloodstream infection. We provide a review of the recent literature about the diagnostic and therapeutic challenges of catheter-related bloodstream infection (CRBSI) in children and its prevention. Variations in blood sampling and limitations in blood culturing interfere with accurate and timely diagnosis of CRBSI. Although novel molecular testing methods appear promising in overcoming some of the present diagnostic limitations of conventional blood sampling in children, they still need to solidly prove their accuracy and reliability in clinical practice. Standardized practices of catheter insertion and care remain the cornerstone of CRBSI prevention although their implementation in daily practice may be difficult. Technology such as CVC impregnation or catheter locking with antimicrobial substances has been shown less effective than anticipated. Despite encouraging results in CRBSI prevention among adults, the goal of zero infection in children is still not in range. More high-quality research is needed in the field of prevention, accurate and reliable diagnostic measures and effective treatment of CRBSI in children.

Modulation of ENaC, CFTR, and iNOS expression in bronchial epithelial cells after stimulation with Staphylococcus epidermidis (94B080) and Staphylococcus aureus (90B083)

Bacteria affect the respiratory epithelium, which is covered by airway surface liquid (ASL) and mucus. Ion concentrations in the ASL are determined by the cystic fibrosis transmembrane conductance regulator (CFTR) and the epithelial Na(+) channel (ENaC). Neonatal sepsis is a major risk factor for subsequent pulmonary disease in preterm newborns. Predominating are coagulase-negative staphylococci (e.g., Staphylococccus epidermidis and Staphylococccus aureus). The aim of this study was to investigate modulation of CFTR, ENaC, mucins, proinflammatory cytokines, and inducible nitric oxide synthase (iNOS) in respiratory epithelial cells after S. epidermidis 94B080 and S. aureus 90B083 exposure. Bronchial epithelial cells were incubated with S. epidermidis 94B080 and S. aureus 90B083 (neonatal blood isolates) for 1-36 h. Expression of CFTR, ENaC, iNOS, and mucins was analyzed by real-time PCR and Western blotting. Release of cytokines was analyzed by ELISA, and production of NO by the Griess assay. Expression of CFTR significantly decreased after 36 h incubation with S. epidermidis and more prominently with S. aureus, whereas S. epidermidis caused a significant increase in the expression of β- and γ-ENaC. Expression of iNOS increased, but NO was not detected. Both staphylococci caused a decrease in the intracellular Ca(2+) concentration. S. aureus induced increased secretion of IL-6, IL-8, and transforming nuclear factor (TNF)-α in a time-dependent manner as compared with S. epidermidis. In conclusion, expression of ENaC, CFTR, and iNOS is modulated by exposure to S. aureus 90B083 and S. epidermidis 94B080. S. aureus is more potent in causing release of IL-6, IL-8, and TNF-α by bronchial epithelial cells as compared with S. epidermidis. The mRNA expression for the mucus proteins MUC2, MUC5AC, and MUC5B could not be measured, neither in the presence nor in the absence of bacteria.

Persistent coagulase-negative staphylococci bacteremia in very-low-birth-weight infants

This study sought to expand current knowledge on the clinical and epidemiological characteristics of persistent coagulase-negative Staphylococcus (CoNS) bacteremia in very-low-birth-weight (VLBW) infants. Background and disease-related data were collected prospectively on 143 VLBW infants diagnosed with CoNS bacteremia at a pediatric tertiary medical center in 1995-2003. Findings were compared between those with persistent (positive blood cultures for >72 h under appropriate treatment ) and nonpersistent disease. Fifty-eight infants (40.6%) were found to have persistent bacteremia. There were no between-group differences in maternal characteristics, mode of delivery, newborn characteristics, dwell time of central venous and umbilical catheters, complications of prematurity, or mean hospital stay. The persistent bacteremia group had significantly higher rates of hypothermia at presentation (37.9% vs. 17.6%, p < 0.04), creatinine >1.2 mg% on treatment day 7 (13.7% vs. 2.4%, p < 0.02; transient phenomenon), and endocarditis (p < 0.03); one infant had an aortic thrombus. Predominantly breast-fed infants had a higher rate of negative cultures within 72 h of appropriate treatment than predominantly formula-fed infants (60% vs. 19%, p < 0.02). In conclusion, persistence of CoNS bacteremia is common in VLBW infants. Endocarditis should be excluded in all infants with persistent disease. Breast-feeding is associated with a shorter disease duration.

Prevention of neonatal late-onset sepsis associated with the removal of percutaneously inserted central venous catheters in preterm infants

OBJECTIVES

Indwelling central venous catheters are the most important risk factors for the development of sepsis attributable to coagulase-negative staphylococci among preterm infants admitted to neonatal intensive care units. In addition, removal of a central venous catheter also may cause coagulase-negative staphylococci sepsis, which may be prevented by the short-term administration of an anti-staphylococcal agent during the procedure of removal. The administration of a specific anti-staphylococcal agent (cefazolin) was evaluated for the prevention of central venous catheter removal-associated coagulase-negative staphylococci sepsis.

DESIGN

A prospective, open, randomized, controlled intervention study.

SETTING

Twenty-eight-bed neonatal intensive care unit at a tertiary care children's hospital.

PATIENTS

Eighty-eight preterm infants (gestational age <37 wks) admitted to the neonatal intensive care unit with indwelling percutaneously inserted central venous catheters.

INTERVENTION

From April 2007 to January 2010, infants were randomized to receive two doses of cefazolin during removal of the percutaneously inserted central venous catheter (intervention group, n = 44) or no antimicrobial agent (control group, n = 44). Percutaneously inserted central venous catheter removal-associated sepsis was defined as sepsis occurring <48 hrs after removal of the percutaneously inserted central venous catheter.

MEASUREMENTS AND MAIN RESULTS

Clinical characteristics and central venous catheter duration did not show differences between both groups. Five infants (11%) of the control group developed coagulase-negative staphylococci sepsis <48 hrs after removal of the percutaneously inserted central venous catheter compared to none (0%) in the intervention group (p = .021).

CONCLUSIONS

Two doses of the anti-staphylococcal agent cefazolin during the procedure of removal of a percutaneously inserted central venous catheter were effective in the prevention of coagulase-negative staphylococci sepsis. It is recommended to include this regimen in the guidelines on management of central venous catheters in very-low-birth-weight infants.

Recently tested strategies to reduce nosocomial infections in the neonatal intensive care unit

Recent years have witnessed a renewed interest in reducing hospital-acquired infections in critically ill patients. We review three recently tested strategies to decrease nosocomial infections specifically in the neonatal intensive care unit. These include improvement of hand hygiene, the incorporation of hand-hygiene practices into broader care bundles, and the prophylactic administration of antimicrobials, especially fluconazole, to infants at high risk prior to the onset of infection. The effectiveness of the first two interventions is well supported, particularly in older patient populations, while the effectiveness of the third is counterbalanced by the threat of the emergence of resistant-organism infections.

Removal of percutaneously inserted central venous catheters in neonates is associated with the occurrence of sepsis

BACKGROUND

Clinical signs of sepsis are frequently observed after removal of a percutaneously inserted central venous catheter (PCVC) in neonates admitted at our Neonatal Intensive Care Unit (NICU). To substantiate this finding and to evaluate the effect of antibiotics administered at the time of removal of a PCVC, we conducted a retrospective study among all infants with a PCVC, admitted at our NICU during 2002 and 2005.

METHODS

Clinical data, infectious complications and use of antibiotics were studied retrospectively.

RESULTS

A PCVC was inserted in 345 infants. Sepsis occurred in 90/345 (26%) infants, in 50/90 (56%) during indwelling PCVC and in 40/90 (44%) after removal of the PCVC. Of the latter 40 sepsis episodes, 24 (60%) occurred within 5 days after removal of a PCVC with a clustering of 21 cases of sepsis within 72 h after the removal. The remaining 16 episodes occurred after 7 days. Administration of antibiotics during removal of the PCVC significantly reduced the incidence of sepsis: 22/213 (10.3%) cases of sepsis occurred when no antibiotics were administered versus 2/132 (1.5%) cases of sepsis when antibiotics were administered (p = 0.002).

CONCLUSION

Our study suggests that peripherally inserted central venous catheters are associated with sepsis not only during the indwelling period of the catheter, but also after removal. Administration of antibiotics targeted at the time of removal of the catheter significantly reduced the incidence of sepsis. Future prospective studies are warranted to confirm this observation.

Vancomycin prophylaxis for late-onset sepsis in very low and extremely low birth weight neonates

LATE-ONSET SEPSIS AMONG very low birth weight (VLBW) and extremely low birth weight (ELBW) neonates is a troubling occurrence. The most recently published data from the National Nosocomial Infection Surveillance system documents 5.4 umbilical- and central line–related bloodstream infections (BSIs) per 1,000 catheter days in infants weighing between 1,001 and 1,500 g.1 For infants weighing 1,000 g or less, the rate is 9.1 infections per 1,000 catheter days. A variety of factors, including prematurity and related relative immunocompromise, altered skin integrity, and multiple invasive procedures, places VLBW and ELBW neonates at risk for infection. Tunneled central catheters or peripherally inserted central catheters (PICCs) clearly add to the risk of infection in these vulnerable patients. In a point prevalence survey of a network of 29 NICUs, researchers found that coagulase-negative Staphylococcus (CoNS) was the causative organism in nearly half (48.3 percent) of the documented bloodstream infections.2 Vancomycin prophylaxis is a potential strategy for the prevention of late-onset sepsis associated with CoNS. This column explores the efficacy and safety of this strategy.

Prophylactic systemic antibiotics to reduce morbidity and mortality in neonates with central venous catheters

BACKGROUND

The use of central venous catheters is recognised as a risk factor for nosocomial infection. Prophylactic antibiotics may be effective in preventing catheter-related blood stream infection in newborns but may also have the undesirable effect of promoting the emergence of resistant strains of micro-organisms.

OBJECTIVES

To determine the effect of prophylactic antibiotics on mortality and morbidity in neonates with central venous catheters.

SEARCH STRATEGY

Searches were done of the Cochrane Neonatal Review Group Specialised Register, MEDLINE from 1950 to April 2007, CINAHL from 1982 to April 2007, and the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 2 2007). Previous reviews (including cross references) were also searched.

SELECTION CRITERIA

Randomised controlled trials or quasi-randomised controlled trials of adequate quality in which either individual newborn infants or clusters of infants were randomised to receive prophylactic antibiotics (not including antifungals) versus placebo or no treatment. Infants must have had central venous catheters, been full term infants less than 28 days old or preterm infants up to 44 weeks (postmenstrual) corrected age.

DATA COLLECTION AND ANALYSIS

Criteria and methods used to assess the methodological quality of the trials: standard methods of the Cochrane Collaboration and its Neonatal Review Group were used. The review authors extracted data independently. Attempts were made to contact study investigators for additional information as required.

MAIN RESULTS

Three small studies have been included in this review. Prophylactic antibiotics in neonates with central venous catheters had no effect on overall mortality (typical RR 0.68, 95% confidence interval 0.31, 1.51). Prophylactic antibiotics in neonates with central venous catheters decreased the rate of proven bacterial sepsis (typical RR 0.38, 95% confidence interval 0.18, 0.82). Prophylactic antibiotics in neonates with central venous catheters decreased the rate of suspected or proven bacterial septicaemia (typical RR 0.40, 95% confidence interval 0.20, 0.78). No resistant organisms colonising infants were identified in any of the studies. No pooled data were available for other important outcome measures such as chronic lung disease or neurodevelopmental outcome.

AUTHORS' CONCLUSIONS

Prophylactic systemic antibiotics in neonates with a central venous catheter reduces the rate of proven or suspected septicaemia. However, this may not be clinically important in the face of no significant difference in overall mortality and the lack of data on long-term neurodevelopmental outcome. Furthermore, there is a lack of data pertaining to the potentially significant disadvantages of this approach such as the selection of resistant organisms. The routine use of prophylactic antibiotics in infants with central venous catheters in neonatal units cannot currently be recommended.

Fusidic acid and heparin lock solution for the prevention of catheter-related bloodstream infections in critically ill neonates: a retrospective study and a prospective, randomized trial

OBJECTIVE

Catheter-related bloodstream infections (CRBSIs) are one of the main morbidities in critically ill neonates. The objective of the present study was to assess the efficacy of a fusidic acid-heparin lock in the prevention of CRBSIs.

DESIGN

A preliminary retrospective study showed that staphylococcal infections were largely prevalent. We planned a prospective, randomized trial to ascertain whether fusidic acid and heparin lock of central venous catheters would reduce the incidence of CRBSIs.

SETTING

Level III neonatal intensive care unit.

PATIENTS

One hundred three neonates were enrolled and randomly assigned to a treatment group (n = 50) or control group (n = 53).

INTERVENTIONS

Fusidic acid (4 mg/mL) and heparin (10 IU/mL) lock in the treatment group.

MEASUREMENTS AND MAIN RESULTS

The treatment group showed significantly lower incidence of CRBSIs (6.6 vs. 24.9 per 1000 catheter days; p < .01; relative risk 0.28; 95% confidence interval 0.13-0.60). No staphylococcal infections occurred in the treatment group, while in the control group Staphylococcus remained the main agent of CRBSI. Cost analysis comparing the present study and for the treatment of CRBSIs proved that antibiotic lock is financially favorable.

CONCLUSIONS

Fusidic acid-heparin lock solution reduced the incidence of CRBSIs in our neonatal intensive care unit. However, we recommend basing antibiotic lock on local CRBSI epidemiology. With regard to fusidic acid, further and broader studies could be useful to confirm our results.

Risk factors for central venous catheter-related infections in pediatric intensive care

OBJECTIVES

To identify risk factors for short-term percutaneously inserted central venous catheter-related infections in children and to evaluate the accuracy of a mortality score in predicting the risk of infection.

METHOD

After reviewing the charts of patients who developed catheter-related infection in a university hospital's pediatric intensive care unit, we conducted a case-controlled study with 51 pairs. Variables related to patients and to catheter insertion and use were analyzed. Risk factors were defined by logistic regression analysis. The accuracy of the Pediatric Risk of Mortality score to discriminate the risk for infection was tested using the Receiver Operating Characteristic curve.

RESULTS

Infection was associated with respiratory failure, patient's length of stay, duration of tracheal intubation, insertion of catheter in the intensive care unit and parenteral nutrition. Insertion site (femoral or internal jugular) was unimportant. Multivariate logistic regression analysis identified the following variables. Risk factors included more than one catheter placement (p=0.014) and duration of catheter use (p=0.0013), and protective factors included concomitant antibiotic use (p=0.0005) and an intermittent infusion regimen followed by heparin filling compared to continuous infusion without heparin (p=0.0002). Pediatric Risk of Mortality did not discriminate the risk of infection.

CONCLUSIONS

Central parenteral nutrition and central venous catheters should be withdrawn as soon as possible. Femoral vein catheterization carries a risk of infection similar to internal jugular catheterization. The Pediatric Risk of Mortality score should not be used to predict the risk of central catheter-related infections.

Study of virulence factors in coagulase-negative staphylococci isolated from newborns

Coagulase-negative staphylococci (CNS) have been identified as the etiological agent in various infections and are currently the microorganisms most frequently isolated in nosocomial infections. However, little is known about the virulence factors produced by CNS that contribute to the pathogenesis of infections caused by these microorganisms. The study of CNS isolated from infectious processes of newborns hospitalized in the Neonatal Unit of the Hospital of the Botucatu Medical School, UNESP, indicated Staphylococcus epidermidis as the most frequently isolated species (77.8%), which was also associated with clinically significant situations. The analysis of virulence factors revealed the production of slime in 20 (17.1%) of all CNS samples isolated and the synthesis of a broad spectrum of enzymes and toxins, including hemolysins (19.6%), lipase (17.1%), lecithinase (3.4%), DNAse (15.4%), thermonuclease (7.7%), and enterotoxin A, B or C (37.6%). Taking into consideration that the etiological importance of CNS has often been neglected, the present investigation confirmed that these microorganisms should not be ignored or classified as mere contaminants.

In-line filters in central venous catheters in a neonatal intensive care unit

Nosocomial sepsis remains an important cause of morbidity in neonatal intensive care units. Central venous catheters (CVCs) and parenteral nutrition (TPN) are major risk factors. In-line filters in the intravenous (IV) administration sets prevent the infusion of particles, which may reduce infectious complications. We randomized infants to in-line filter (for clear fluids and lipid emulsions) or no filter placement. Sepsis, nursing time and costs were assessed. IV sets without filters were changed every 24 h, IV-sets with filters every 96 h. Of 442 infants with a CVC, 228 were randomized to filter placement, 214 to no filter. No differences were found in clinical characteristics, CVC-use, and catheter days. Nosocomial sepsis occurred in 37 (16.2%) infants with filters, in 35 (16.3%) in the group without filter (NS). Nursing time to change the IV-administration sets was 4 min shorter in the filter-group (P<0.05). Costs of materials used were comparable. In conclusion, the incidence of sepsis when using filters was not reduced but the nursing time for changing the intravenous sets was reduced without a difference in costs.

Use of Vancomycin-Containing Lock or Flush Solutions for Prevention of Bloodstream Infection Associated with Central Venous Access Devices: A Meta-Analysis of Prospective, Randomized Trials

BACKGROUND

Prolonged exposure to central venous access devices carries significant risk of device-associated bloodstream infection (BSI), which is associated with morbidity, added health care costs, and attributable mortality. We aimed to determine the efficacy of vancomycin-heparin lock or flush solution in preventing BSI in patients being treated with long-term central venous intravascular devices (IVDs).

METHODS

We collected data from January 1966 to January 2006 from multiple computerized databases and compiled reference lists of identified articles. We identified prospective, randomized controlled trials comparing a vancomycin-heparin lock or flush solution with heparin alone for prevention of BSI associated with long-term central venous IVDs. Using a standardized form, we abstracted data regarding study quality, patient characteristics, and incidence of BSI.

RESULTS

Seven randomized, controlled trials involving a total of 463 patients being treated with IVDs met the inclusion criteria; 5 studies were conducted among patients with cancer, 1 among a critically ill neonatal population, and 1 among patients with cancer or who required parenteral nutrition. We could not detect publication bias. The summary risk ratio with a vancomycin heparin-lock solution for IVD-associated BSI was 0.49 (95% confidence interval [CI], 0.26-0.95; P = .03). Results of the test for heterogeneity were statistically significant; however, when a single study was removed from the analysis, heterogeneity was no longer present. Use of vancomycin as a true lock solution--instilling it for a defined period, rather than simply flushing it directly through the device--conferred a much greater benefit, with a risk ratio of 0.34 (95% CI, 0.12-0.98; P = .04). The 2 studies that performed prospective surveillance cultures to identify colonization or infection by vancomycin-resistant organisms did not find an increased risk.

CONCLUSIONS

Use of a vancomycin lock solution in high-risk patient populations being treated with long-term central IVDs reduces the risk of BSI. The use of an anti-infective lock solution warrants consideration for patients who require central access but who are at high risk of BSI, such as patients with malignancy or low-birthweight neonates.

Pediatric catheter-related bloodstream infections: latest strategies to decrease risk

Central venous catheters are often mandatory devices when caring for critically ill children. They are required to deliver medications, nutrition, and blood products, as well as for monitoring hemodynamic status and drawing laboratory samples. Any foreign object that is introduced to the body is at risk for infection. Central venous catheters carry a particularly high risk of infection and these infections can be life threatening. Advanced practice nurses possess the power to influence catheter-related line infections in their critical care units. Understanding current recommendations for catheter material selection, site selection, site preparation, and site care can affect rates of catheter-related bloodstream infections. This article discusses risk factors for developing catheter-related bloodstream infections in critically ill children, as well as measures to decrease incidence of catheter-related bloodstream infections, including a review of recommendations from the Centers for Disease Control and Prevention.

A vancomycin-heparin lock solution for prevention of nosocomial bloodstream infection in critically ill neonates with peripherally inserted central venous catheters: a prospective, randomized trial

OBJECTIVE

Critically ill neonates are at high risk for vascular catheter-related bloodstream infection (CRBSI), most often caused by coagulase-negative staphylococci. Most CRBSIs with long-term devices derive from intraluminal contaminants. The objective of this study was to ascertain the safety and the efficacy of a vancomycin-heparin lock solution for prevention of CRBSI.

METHODS

A prospective, randomized double-blind trial was conducted during 2000-2001 at a community hospital level III NICU. Very low birth weight and other critically ill neonates with a newly placed peripherally inserted central venous catheter were randomized to have the catheter locked 2 or 3 times daily for 20 or 60 minutes with heparinized normal saline (n = 43) or heparinized saline that contained vancomycin 25 microg/mL (n = 42). The origin of each nosocomial bloodstream infection (BSI) was studied by culturing skin, catheter hubs, and implanted catheter segments and blood cultures, demonstrating concordance by restriction-fragment DNA subtyping. Surveillance axillary and rectal cultures were performed to detect colonization by vancomycin-resistant organisms. The main outcome measures were (1) CRBSIs and (2) colonization or infection by vancomycin-resistant Gram-positive bacteria.

RESULTS

Two (5%) of 42 infants in the vancomycin-lock group developed a CRBSI as compared with 13 (30%) of 43 in the control group (2.3 vs 17.8 per 1000 catheter days; relative risk: 0.13; 95% confidence interval: 0.01-0.57). No vancomycin-resistant enterococci or staphylococci were recovered from any cultures. Vancomycin could not be detected in the blood of infants who did not receive systemic vancomycin therapy. Twenty-six neonates (8 vancomycin-lock group, 18 control group) had at the end of a catheter-lock period asymptomatic hypoglycemia that resolved promptly when glucose-containing intravenous fluids were restarted.

CONCLUSIONS

Prophylactic use of a vancomycin-heparin lock solution markedly reduced the incidence of CRBSI in high-risk neonates with long-term central catheters and did not promote vancomycin resistance but was associated with asymptomatic hypoglycemia. The use of an anti-infective lock solution for prevention of CRBSI with long-term intravascular devices has achieved proof of principle and warrants selective application in clinical practice.

Catheter-related infections in children treated with hemodialysis

Infectious complications of the central venous catheter (CVC) are a major source of morbidity among children treated with hemodialysis (HD), with catheter-related bloodstream infections (CRBSI) being the most important clinical manifestations. As only a few studies of children on HD have been published, the management of CVC-related infections in this population is mainly based on data derived from adults or occasionally from children not affected by end-stage renal disease (ESRD). The aim of this review is to discuss current knowledge concerning the epidemiology, prevention, and treatment of catheter-related infections in children on HD. Catheters impregnated with antibiotics/antiseptics, lock antibiotic prophylaxis, nasal mupirocin, and the application of ointments at the exit-site have all been proposed as means of reducing the risk of CVC infections, but their real efficacy in the pediatric population has not yet been demonstrated. Furthermore, it is not clear how long antibiotic therapy should be continued, and there is still debate as to whether the catheter has to be removed. We propose some practical guidelines for the management of CRBSI in children with percutaneously inserted and surgically implanted HD catheters, but a number of unresolved clinical issues still remain, which will require prospective clinical trials specifically performed in pediatric patients with ESRD.

Vancomycin usage in central venous catheters in a neonatal intensive care unit

BACKGROUND

We previously reported that vancomycin in hyperalimentation solution reduces catheter-related infections in the neonatal intensive care unit. Since June 1993 vancomycin (25 microg/ml) was routinely added to central venous catheter solutions, primarily hyperalimentation solution. Because the prophylactic use of vancomycin could lead to the emergence of resistant organisms, the decision to discontinue this practice was made in April of 1999. The use of vancomycin was reserved for documented infections with vancomycin-susceptible organisms.

OBJECTIVE

To compare catheter longevity, rate of laboratory-confirmed blood stream infections and total vancomycin exposure between two 18-month periods before and after the cessation of prophylactic vancomycin use.

METHODS

Data were evaluated for every neonate in whom a percutaneous central venous catheter was placed.

RESULTS

There were 394 neonates enrolled. No statistically significant difference was identified between the two periods regarding the mean catheter days or number of catheters per patient. There was a higher rate of Gram-negative laboratory-confirmed blood stream infections during Period I in patients with percutaneous central venous catheters in place. There were more isolates of coagulase-negative staphylococci in Period II, resulting in more frequent vancomycin therapy institution and thus an overall increase in the amount of vancomycin used in that period

CONCLUSION

Discontinuing the use of prophylactic vancomycin resulted in exposure of fewer neonates to vancomycin but a higher total amount of vancomycin used. The impact of low dose widespread exposure to vancomycin vs. high dose limited exposure on the microbiologic flora in the neonatal intensive care unit should be further examined.

Vancomycin

This review describes the use of vancomycin in neonates over the last three decades. Given the relation of late-onset neonatal septicaemia to outcome and the increase in coagulase-negative staphylococcal infection as causative organism, vancomycin remains an important antibacterial in the neonatal intensive care unit. The pharmacokinetic behaviour of vancomycin in neonates can be adequately described by a one- or two-compartment model and is mainly determined by postconceptional age and renal function. In neonates, a patent ductus arteriosus as well as treatment with indomethacin or extracorporeal membrane oxygenation (ECMO) leads to an increase in volume of distribution and a decrease in clearance. Microbiological studies in vitro have shown that an increase in vancomycin concentrations above the minimum inhibitory concentration does not result in more effective killing. The microbiological and clinical efficacy of vancomycin in neonates has only been studied explicitly in a restricted number of patients. There are no definitive data relating serum concentrations to effect in this patient group. Vancomycin-related nephrotoxicity and ototoxicity in neonates is rare, and no clear relation to serum concentrations has been demonstrated. Based on the pharmacokinetic profile of vancomycin in neonates, several administration regimens have been constructed. Recent guidelines have suggested that dosage can be independent of gestational age or postconceptional age in neonates without renal failure. In patients with renal failure, therapy can be adequately tailored by using a regimen based on serum creatinine. The usefulness of routine monitoring of peak serum concentrations is doubtful based on the current literature. Recent research demonstrates a shift towards taking only routine trough serum concentrations in order to optimise efficacy. Patients with renal failure and other special subpopulations, such as patients exposed to ECMO or indomethacin, need to be monitored more closely.

Guidelines for the Prevention of Intravascular Catheter–Related Infections

These guidelines have been developed for practitioners who insert catheters and for persons responsible for surveillance and control of infections in hospital, outpatient, and home health-care settings. This report was prepared by a working group comprising members from professional organizations representing the disciplines of critical care medicine, infectious diseases, health-care infection control, surgery, anesthesiology, interventional radiology, pulmonary medicine, pediatric medicine, and nursing. The working group was led by the Society of Critical Care Medicine (SCCM), in collaboration with the Infectious Disease Society of America (IDSA), Society for Healthcare Epidemiology of America (SHEA), Surgical Infection Society (SIS), American College of Chest Physicians (ACCP), American Thoracic Society (ATS), American Society of Critical Care Anesthesiologists (ASCCA), Association for Professionals in Infection Control and Epidemiology (APIC), Infusion Nurses Society (INS), Oncology Nursing Society (ONS), Society of Cardiovascular and Interventional Radiology (SCVIR), American Academy of Pediatrics (AAP), and the Healthcare Infection Control Practices Advisory Committee (HICPAC) of the Centers for Disease Control and Prevention (CDC) and is intended to replace the Guideline for Prevention of Intravascular Device–Related Infections published in 1996. These guidelines are intended to provide evidence-based recommendations for preventing catheter-related infections. Major areas of emphasis include 1) educating and training health-care providers who insert and maintain catheters; 2) using maximal sterile barrier precautions during central venous catheter insertion; 3) using a 2% chlorhexidine preparation for skin antisepsis; 4) avoiding routine replacement of central venous catheters as a strategy to prevent infection; and 5) using antiseptic/antibiotic impregnated short-term central venous catheters if the rate of infection is high despite adherence to other strategies (i.e., education and training, maximal sterile barrier precautions, and 2% chlorhexidine for skin antisepsis). These guidelines also identify performance indicators that can be used locally by health-care institutions or organizations to monitor their success in implementing these evidence-based recommendations.

Guidelines for the prevention of intravascular catheter-related infections. The Hospital Infection Control Practices Advisory Committee, Center for Disease Control and Prevention, U.S

These guidelines have been developed for practitioners who insert catheters and for persons responsible for surveillance and control of infections in hospital, outpatient, and home health-care settings. This report was prepared by a working group comprising members from professional organizations representing the disciplines of critical care medicine, infectious diseases, health-care infection control, surgery, anesthesiology, interventional radiology, pulmonary medicine, pediatric medicine, and nursing. The working group was led by the Society of Critical Care Medicine (SCCM), in collaboration with the Infectious Disease Society of America (IDSA), Society for Healthcare Epidemiology of America (SHEA), Surgical Infection Society (SIS), American College of Chest Physicians (ACCP), American Thoracic Society (ATS), American Society of Critical Care Anesthesiologists (ASCCA), Association for Professionals in Infection Control and Epidemiology (APIC), Infusion Nurses Society (INS), Oncology Nursing Society (ONS), Society of Cardiovascular and Interventional Radiology (SCVIR), American Academy of Pediatrics (AAP), and the Healthcare Infection Control Practices Advisory Committee (HICPAC) of the Centers for Disease Control and Prevention (CDC) and is intended to replace the Guideline for Prevention of Intravascular Device-Related Infections published in 1996. These guidelines are intended to provide evidence-based recommendations for preventing catheter-related infections. Major areas of emphasis include 1) educating and training health-care providers who insert and maintain catheters; 2) using maximal sterile barrier precautions during central venous catheter insertion; 3) using a 2% chlorhexidine preparation for skin antisepsis; 4) avoiding routine replacement of central venous catheters as a strategy to prevent infection; and 5) using antiseptic/antibiotic impregnated short-term central venous catheters if the rate of infection is high despite adherence to other strategies (ie, education and training, maximal sterile barrier precautions, and 2% chlorhexidine for skin antisepsis). These guidelines also identify performance indicators that can be used locally by health-care institutions or organizations to monitor their success in implementing these evidence-based recommendations.

The promise of novel technology for the prevention of intravascular device-related bloodstream infection. II. Long-term devices

Intravascular devices (IVDs) are widely used for vascular access but are associated with a substantial risk of IVD-related bloodstream infection (BSI). The development of novel technologies based on our understanding of pathogenesis promises a quantum reduction in IVD-related infections in an era of growing nursing shortage. Infections of long-term IVDs (most are in place for > or =10 days), including cuffed and tunneled central venous catheters (CVCs), implanted subcutaneous central venous ports, and peripherally inserted central catheters (PICCs), are primarily due to microorganisms that gain access to the catheter hub and lumen. Novel securement devices and antibiotic lock solutions have been shown to reduce the risk of IVD-related BSI in prospective randomized trials. The challenge for the future will be to identify new preventative technologies and to begin to more-widely adapt those technologies that have already been shown to be efficacious and cost effective.

Management of intravascular devices to prevent infection

Intravenous therapy is an essential part of clinical care used in a wide variety of healthcare settings. Thus, intravenous catheters have become indispensable to clinical practice. However, catheter-related-bloodstream infections (CR-BSIs) are a major source of morbidity and mortality, especially in hospital patients. Strategies to prevent infection need to change and develop to reflect the advances in technology and delivery of health care. Current guidance recommends a number of strategies to reduce the incidence of CR-BSIs. These include applying the principles of asepsis, the choice of catheter material, the site of insertion and when to replace equipment used. This article reviews the guidelines for current clinical practice.

Risk factors for central vascular catheter-associated bloodstream infections among patients in a neonatal intensive care unit

The aim of this study was to identify risk factors for catheter-associated bloodstream infection (CABSI) in neonates. We undertook a prospective investigation of the potential risk factors for CABSI (patient-related, treatment-related and catheter-related) in a neonatal intensive care unit (NICU) using univariate and multivariate techniques. We also investigated the relationship between catheter hub and catheter exit site colonization with CABSI.Thirty-five episodes of CABSI occurred in 862 central catheters over a period of 8028 catheter-days, with a cumulative incidence of 4.1/100 catheters and an incidence density of 4.4/1000 catheter days. Factors independently associated with CABSI were: catheter hub colonization (odds ratio [OR] = 44.1, 95% confidence interval [CI] = 14.5 to 134.4), exit site colonization (OR = 14.4, CI = 4.8 to 42.6), extremely low weight (< 1000 g) at time of catheter insertion (OR = 5.13, CI = 2.1 to 12.5), duration of parenteral nutrition (OR=1.04, CI=1.0 to 1.08) and catheter insertion after first week of life (OR = 2.7, CI = 1.1 to 6.7). In 15 (43%) out of the 35 CABSI episodes the catheter hub was colonized, in nine (26%) cases the catheter exit site was colonized and in three (9%) cases colonization was found at both sites. This prospective cohort study on CABSI in a NICU identified five risk factors of which two can be used for risk-stratified incidence density description (birthweight and time of catheter insertion). It also emphasized the importance of catheter exit site, hub colonization and exposure to parenteral nutrition in the pathogenesis of CABSI.

Microbiology and risk factors for catheter exit-site and -hub colonization in neonatal intensive care unit patients

OBJECTIVE

To identify risk factors and describe the microbiology of catheter exit-site and hub colonization in neonates.

DESIGN

During a period of 2 years, we prospectively investigated 14 risk factors for catheter exit-site and hub colonization in 862 central venous catheters in a cohort of 441 neonates. Cultures of the catheter exit-site and hub were obtained using semiquantitative techniques at time of catheter removal.

SETTING

A neonatal intensive care unit at a university hospital.

RESULTS

Catheter exit-site colonization was found in 7.2% and hub colonization in 5.3%. Coagulase-negative staphylococci were predominant at both sites. Pathogenic flora were found more frequently at the catheter hub (36% vs 14%; P<.05). Through logistic regression, factors associated with exit-site colonization were identified as umbilical insertion (odds ratio [OR], 8.1; 95% confidence interval [CI95], 2.35-27.6; P<.001), subclavian insertion (OR, 54.6; CI95, 12.2-244, P<.001), and colonization of the catheter hub (OR, 8.9; CI, 3.5-22.8; P<.001). Catheter-hub colonization was associated with total parenteral nutrition ([TPN] OR for each day of TPN, 1.056; CI95, 1.029-1.083; P<.001) and catheter exit-site colonization (OR, 6.11; CI95, 2.603-14.34; P<.001). No association was found between colonization at these sites and duration of catheterization and venue of insertion, physician's experience, postnatal age and patient's weight, ventilation, steroids or antibiotics, and catheter repositioning.

CONCLUSION

These data support that colonization of the catheter exit-site is associated with the site of insertion and colonization of the catheter hub with the use of TPN. There is a very strong association between colonization at both catheter sites.

Nosocomial coagulase negative staphylococcal (CoNS) catheter-related sepsis in preterm infants: definition, diagnosis, prophylaxis, and prevention

Nosocomial infections with coagulase negative staphylococcus (CoNS) are a frequent and significant cause of morbidity in the preterm infant. Infections diagnosed after the first 72 hours of life are arbitrarily deemed to be "nosocomial." There are many difficulties encountered in efforts to evaluate and compare nosocomial sepsis in the NICU. An issue of primary concern is the lack of uniformity in the definition of sepsis in the NICU. Based on the frequency of positive blood cultures in infants less than 1000 g, it appears reasonable to evaluate methods for the prevention of nosocomial sepsis. These include prophylactic antibiotic administration, antiseptic impregnated catheters, and the use of an antibiotic lock technique.

National guidelines for the judicious use of glycopeptides in Belgium

OBJECTIVE

The 'HICPAC guidelines', published in the USA in 1995 stressed the crucial role of restrictive usage of glycopeptides in the strategy to limit the emergence and spread of resistant enterococci. Because controversy still remains in Belgium on the necessity and feasability of restricting glycopeptide usage, the infectious diseases advisory board (IDAB) developed a consensus statement on the judicious use of glycopeptides in Belgium.

METHODS

The literature on the indications for glycopeptide treatment was reviewed, categorized and discussed by a working party of the IDAB.Consequently, the IDAB reached consensus on the warranted indications for glycopeptide use in Belgium.

RESULTS

The opinion of the IDAB-members is reported in a consensus statement specifying the indications for treatment and for prophylaxis with glycopeptide antimicrobials, as well as the situations where glycopeptides should not be used, taking into account the specific epidemiology of bacterial resistance, the availability of antibiotics and the common prescribing practices in Belgium.

CONCLUSIONS

The IDAB concludes that restrictive usage of glycopeptides must also be a priority in Belgium. Guidelines on the judicious use of these antibiotics adapted to the national situations must contribute to this objective.

Vancomycin for prophylaxis against sepsis in preterm neonates

BACKGROUND

Nosocomial, late onset sepsis occurs in up to 50% of infants of less than 1000gm at birth. The commonest organism isolated is coagulase negative staphylococcus (CoNS). A number of studies have evaluated the efficacy or prophylactic low dose vancomycin given either as a continuous infusion added to the infant's hyperalimentation fluid or by intermittent intravenous administration and these studies in very low birth weight infants are the subject of this review.

OBJECTIVES

To evaluate the safety and efficacy of vancomycin prophylaxis for the prevention of late-onset sepsis, coagulase negative staphylococcal sepsis, mortality, and effects on length of stay, total vancomycin exposure, evidence of vancomycin toxicity, and the development of vancomycin resistant organisms in the preterm neonate.

SEARCH STRATEGY

Searches were made of Medline, (MeSH terms: Vancomycin and Sepsis; limits: age groups, newborn infants), HealthStar and EMBase, electronic abstracts, personal files and conference proceedings.

SELECTION CRITERIA

Randomized controlled trials which compared the incidence of sepsis and mortality in preterm neonates receiving vancomycin prophylaxis versus a control group receiving no prophylaxis.

DATA COLLECTION AND ANALYSIS

Data regarding clinical outcomes including the overall incidence of sepsis, the incidence of coagulase negative staphylococcal sepsis, mortality, length of stay, total vancomycin exposure, evidence of vancomycin toxicity, and the development of vancomycin resistant organisms were excerpted from previous clinical trials. Data analysis was done in accordance with the standards of the Cochrane Neonatal Review Group.

MAIN RESULTS

The administration of prophylactic vancomycin reduced the incidence of both total neonatal nosocomial sepsis and coagulase negative staphylococcal sepsis in eligible preterm infants. Mortality, length of stay, and evidence of vancomycin toxicity were not significantly different between the two groups. There was insufficient evidence to ascertain the risks of development of vancomycin resistant organisms in the nurseries involved in these trials.

REVIEWER'S CONCLUSIONS

The use of prophylactic vancomycin in low doses reduces the incidence of nosocomial sepsis in the neonate. The methodologies of these studies may have contributed to the low rate of sepsis in the treated groups, as the blood cultures drawn from central lines may have failed to grow due to the low levels of vancomycin in the infusate. Although there is a theoretical concern regarding the development of resistant organisms with the administration of prophylactic antibiotic, there is insufficient evidence to ascertain the risks of development of vancomycin resistant organisms. Few clinically important benefits have been demonstrated for very low birth weight infants treated with prophylactic vancomycin. It therefore appears that routine prophylaxis with vancomycin should not be undertaken at present.

Clinical outcome of cephalothin versus vancomycin therapy in the treatment of coagulase-negative staphylococcal septicemia in neonates: relation to methicillin resistance and mec A gene carriage of blood isolates

OBJECTIVE

Coagulase-negative staphylococci (CONS) are the most common causative agents in neonatal nosocomial septicemia. Because of widespread methicillin resistance among CONS, empiric therapy with vancomycin is recommended as the primary antibiotic regimen for these infections. In our unit, empiric treatment of nosocomially acquired septicemia consists of cephalothin and gentamicin, which are adjusted subsequently according to the determined bacterial susceptibility profile. Vancomycin is initiated only when the patient has been treated recently with cephalothin or when intravascular lines or endotracheal tube are colonized with oxacillin/cephalothin-resistant CONS strains. The aim of the present study was to evaluate the efficacy of our antibiotic regimen for CONS septicemia, in relation to methicillin-resistance and the carriage of mec A gene, encoding methicillin resistance, among CONS blood isolates from our unit.

METHODS

Clinical symptoms of septicemia, clinical outcome, and laboratory parameters of septicemia (C-reactive protein) were studied retrospectively in 66 patients with CONS septicemia. The diagnosis of septicemia was made by the attending neonatologist and was defined by clinical symptoms of septicemia in the presence of a positive finding of a blood culture test, which was performed using a defined protocol. All CONS blood isolates were included to determine mec A gene carriage.

RESULTS

In the 66 patients, three treatment categories were distinguished: treatment with cephalothin (25 patients, 38%); with vancomycin (15 patients, 23%); and primary treatment with cephalothin, switched subsequently to vancomycin (26 patients, 39%). It was found that 92% of all CONS blood isolates (61/66) were mec A-positive. Concordance of mec A gene carriage with methicillin/oxacillin resistance was found in 56 of 66 isolates (85%); 10 of 61 (16%) isolates that were mec A-positive were determined as oxacillin-susceptible. Although 22 of the 25 blood isolates of the cephalothin-treated patients were mec A-positive, clinical recovery was uneventful. In the 26 patients in whom antibiotic therapy was switched from cephalothin to vancomycin, two strains were cephalothin-susceptible and 8 patients already had recovered clinically before the switch, which was based solely on susceptibility test results.

CONCLUSIONS

Cephalothin was found to be clinically efficacious in the treatment of neonatal CONS septicemia, despite a steadily increasing mec A gene carriage of CONS blood isolates in our neonatal intensive care unit and a corresponding high methicillin/oxacillin resistance. Hence, cephalothin remained the antibiotic of first choice in the treatment of CONS septicemia in our unit, with vancomycin selected exclusively for cases not responding to initial cephalothin treatment, or for patients developing CONS septicemia during or after recent cephalothin treatment. By applying this approach in our unit, we were able to reduce vancomycin use from 62% in 1994 to 1995 to 21% in 1997. This shows that such a policy may result in an important reduction of vancomycin use, which may aid in postponing the threatening emergence of vancomycin resistance among Gram-positive cocci.

Emergence of vancomycin resistance in Staphylococcus aureus. Glycopeptide-Intermediate Staphylococcus aureus Working Group

BACKGROUND

Since the emergence of methicillin-resistant Staphylococcus aureus, the glycopeptide vancomycin has been the only uniformly effective treatment for staphylococcal infections. In 1997, two infections due to S. aureus with reduced susceptibility to vancomycin were identified in the United States.

METHODS

We investigated the two patients with infections due to S. aureus with intermediate resistance to glycopeptides, as defined by a minimal inhibitory concentration of vancomycin of 8 to 16 microg per milliliter. To assess the carriage and transmission of these strains of S. aureus, we cultured samples from the patients and their contacts and evaluated the isolates.

RESULTS

The first patient was a 59-year-old man in Michigan with diabetes mellitus and chronic renal failure. Peritonitis due to S. aureus with intermediate resistance to glycopeptides developed after 18 weeks of vancomycin treatment for recurrent methicillin-resistant S. aureus peritonitis associated with dialysis. The removal of the peritoneal catheter plus treatment with rifampin and trimethoprim-sulfamethoxazole eradicated the infection. The second patient was a 66-year-old man with diabetes in New Jersey. A bloodstream infection due to S. aureus with intermediate resistance to glycopeptides developed after 18 weeks of vancomycin treatment for recurrent methicillin-resistant S. aureus bacteremia. This infection was eradicated with vancomycin, gentamicin, and rifampin. Both patients died. The glycopeptide-intermediate S. aureus isolates differed by two bands on pulsed-field gel electrophoresis. On electron microscopy, the isolates from the infected patients had thicker extracellular matrixes than control methicillin-resistant S. aureus isolates. No carriage was documented among 177 contacts of the two patients.

CONCLUSIONS

The emergence of S. aureus with intermediate resistance to glycopeptides emphasizes the importance of the prudent use of antibiotics, the laboratory capacity to identify resistant strains, and the use of infection-control precautions to prevent transmission.

Low-dosage prophylactic vancomycin in central-venous catheters for neonates

Neonatal infectious pathology remains one of the main causes of morbidity and mortality in this age group. The introduction of plasticized catheters for the administration of medication, fluidotherapy and parenteral nutrition was a significant advance in treatment of patients at risk, but also led to the appearance of infectious complications. Negative coagulase staphylococcus is the principal pathogen in most neonatal intensive care units. Recent studies have examined the prophylactic use of vancomycin in preterm babies receiving parenteral nutrition. We have evaluated the efficacy of this procedure, applied via the central venous catheters employed for all neonates, within the intensive care unit over a period of one year. Prophylactic vancomycin administered via the catheters significantly reduced the incidence of Gram-positive infections, despite the presence within this group of a greater number of septic risk factors than in the control group.

Incidence, presenting features, risk factors and significance of late onset septicemia in very low birth weight infants. The National Institute of Child Health and Human Development Neonatal Research Network

BACKGROUND

Septicemia is a major antecedent of morbidity and mortality in very low birth weight (501- to 1500-g) infants. Our purpose was to determine prospectively the incidence, clinical presentation, laboratory features, risk factors, morbidity and mortality associated with late onset septicemia in infants 501 to 1500 g.

METHODS

Clinical data were prospectively collected for 2416 infants enrolled in a multicenter trial to determine the efficacy of intravenous immunoglobulin in preventing nosocomial infections. Septicemia was confirmed by positive blood culture in 395 symptomatic infants. Multivariate analyses of factors associated with septicemia were performed.

RESULTS

Sixteen percent of VLBW infants developed septicemia at a median age of 17 days. Factors associated with septicemia by logistic regression included male gender, lower gestational age and birth weight and decreased baseline serum IgG concentrations. Increasing apnea (55%), feeding intolerance, abdominal distension or guaiac-positive stools (43%), increased respiratory support (29%), lethargy and hypotonia (23%) were the dominant presenting features of septicemia. An abnormal white blood cell count (46%), unexplained metabolic acidosis (11%) and hyperglycemia (10%) were the most common laboratory indicators. Septicemic infants, compared with nonsepticemic infants, had significantly increased mortality (21% vs. 9%), longer hospital stay (98 vs. 58 days) and more serious morbidity, including severe intraventricular hemorrhage, bronchopulmonary dysplasia and increased ventilator days (P < 0.001).

CONCLUSIONS

Late onset septicemia is common in very low birth weight infants, and the rate is inversely proportional to gestational age and birth weight. Septicemia is more common in males and those with low initial serum IgG values. A set of clinical signs (apnea, bradycardia, etc.) and laboratory values (leukocytosis, immature white blood cells and neutropenia) increase the probability of late onset sepsis, but they have poor positive predictive value.

Selective use of vancomycin to prevent coagulase-negative staphylococcal nosocomial bacteremia in high risk very low birth weight infants

OBJECTIVE

To determine whether vancomycin added to parental nutrition (PN) fluids could prevent nosocomial infections in very low birth weight newborns and which infants would benefit most from prophylaxis.

DESIGN

Double blind, randomized controlled study.

SETTING AND STUDY POPULATION

Very low birth weight infants receiving PN in a tertiary neonatal intensive care unit.

METHODS

Thirty-eight infants with and without central vascular catheters were randomized to receive no medication or 25 microg/ml vancomycin added to PN for the duration of the infant's PN requirements.

RESULTS

The addition of 25 microg/ml vancomycin to PN prevented bacteremia in very low birth weight infants receiving PN. There was a significant reduction in the number of coagulase-negative staphylococcal (CONS) bacteremias (defined as isolation of the same organism from two positive blood cultures) during PN (5 vs. 0; P = 0.037) as well as the total number of bacteremias and fungemias (9 vs. 1; P = 0.036). The total number of hospital days (108 +/- 13 vs. 76 +/- 6; P = 0.039) were reduced in infants receiving vancomycin. Infants with birth weights of < 1000 g who received corticosteroids for treatment of chronic lung disease benefitted most from treatment. No vancomycin-resistant strains of CONS or enterococci were detected during the study period.

CONCLUSIONS

Prophylactic treatment with vancomycin effectively prevented CONS bacteremia under the conditions of the study. Its use was most effective in infants with birth weights of <1000 g.

Positive blood cultures for coagulase-negative staphylococci in neonates: does highly selective vancomycin usage affect outcome?

The implication of highly-selective vancomycin usage on the outcome for infants with positive blood cultures for coagulase-negative staphylococci (CONS) was assessed retrospectively. The analysis was performed on partly prospective collected data from infants under 3 months of age with a least one CONS-positive blood culture in the neonatal intensive care unit at the Soroka University Medical Center between 1990 and 1996. During the study period, 239 episodes of CONS-positive blood cultures were identified from among 64,226 live births (3.7 per 1,000). Vancomycin was administered in 22 (9%) episodes, in all cases only after identification of the bacteria. The remaining 217 episodes were managed either without antibiotics or with continuation or initiation of empiric antibiotic therapy (usually ceftazidime +/- ampicillin) for suspected sepsis. Severity of the initial illness, subsequent morbidity and mortality were low regardless of the treatment administered. Only a single case of a blood-borne vancomycin resistant gram-positive organism was observed during the study period. The approach to CONS-positive blood cultures in neonates used here was associated with low morbidity and mortality. These findings support a policy of highly selective vancomycin usage in an era of emerging vancomycin resistance.

Low-dose vancomycin prophylaxis reduces coagulase-negative staphylococcal bacteraemia in very low birthweight infants

Very low birthweight (VLBW) infants undergoing neonatal intensive care are at risk of infection with coagulase-negative staphylococci (CONS). This study investigates the efficacy of twice daily, 1 h infusions of vancomycin (5 mg kg) in reducing CONS infection in VLBW infants receiving parenteral nutrition. Of 72 infants in the study, 37 were randomized to vancomycin and 35 to the control group. Clinical variables and mortality were similar in both groups. In the vancomycin group, 11 infants had one or more episodes of CONS bacteraemia compared with 17 in the control group. Two babies in the treatment group had more than one episode of CONS bacteraemia, compared with nine in the control group (P = 0.02). There were 13 episodes of CONS bacteraemia in the vancomycin group compared with 29 in the control group. When only positive blood-cultures associated with a rise in C-reactive protein were considered, there were six episodes of CONS bacteraemia in the vancomycin group compared with 18 in the control group. Similarly there were five infants with one or more CONS infections compared with 11 in controls and one with more than one episode compared with six in the control group (P = 0.05). Prophylaxis with intermittent low-dose vancomycin infusions may help reduce recurrent CONS bacteraemia in VLBW infants receiving parenteral nutrition.

Comparison of vancomycin and teicoplanin for prophylaxis of sepsis with coagulase negative staphylococci (CONS) in very low birth weight (VLBW) infants

A prospective randomized study was performed to evaluate the efficacy of a low dose (5 mg/kg/day bid) vancomycin compared with a low dose (5 mg/kg/day once daily) teicoplanin therapy to prevent CONS sepsis in VLBW-infants. All infants received this therapy after their 4th day of life or after an eventual therapy of early onset sepsis as long as an i.v. line was in place or 1500 g body weight. Twenty-seven infants were treated with vancomycin (birth weight 1103 +/- 286 g, gest. age 28.8 +/- 1.9 weeks), 28 with teicoplanin (birth weight 1133 +/- 226 g, gest. age 29.04 +/- 2.2 weeks). The infants were observed for clinical and laboratory signs of sepsis. On day 4 of therapy and every 3rd day during therapy serum creatinine levels, tracheal aspirates, stool cultures and vancomycin/teicoplanin peak and trough levels were obtained. We could not detect any case of blood culture positive sepsis and 1 case of suspected sepsis (neg. blood cultures) in both groups, as compared with a former CONS sepsis rate of 24% in our institution's VLBW infants without antibiotic prophylaxis. Nine patients in the vancomycin and five in the teicoplanin group had tracheal colonization with CONS. In both groups peak and trough levels of antibiotics were in the bactericidal range. Serum creatinine was not normal in both groups. We conclude that teicoplanin is preventing CONS sepsis as well is vancomycin. The minimal inhibitory concentrations of both antibiotics against grampositive isolates in units using this strategy have to be observed carefully to detect emerging resistance.

Nosocomial sepsis in neonates with single lumen vascular catheters

Catheter-related sepsis is commonly encountered in the neonatal intensive care unit. We retrospectively studied infants with vascular catheters at 2 NICUs. Data were obtained from the computerised admission records available at both the hospitals. Our aims were to describe the clinical and microbial profile of nosocomial sepsis in infants with vascular catheters [umbilical artery (UA), umbilical venous (UV), central venous Broviac (CV), percutaneously placed central venous (PC), peripheral artery (PA)], and to determine the association between catheter type, duration and sepsis in a subset of the population. Nosocomial sepsis (positive blood culture after the 3rd postnatal day) occurred in 217 of 2091 (10.4%) infants. Infected infants, in contrast to non-infected, had a significantly (P < 0.001) greater number of multiple catheters (2.3 vs 1.4) had lower birth weights (1.2 vs 2.1 kg), were younger (28 vs 33 weeks) and had lower 1 and 5 minute Apgar scores (4.3 and 6.7 vs 5.5 and 7.4). The most common organism was coagulase negative Staphylococcus. In a subset population as analyses revealed, longer duration of UA use was associated with higher infection rates [13.6% with UA use for > or = 8 days vs 1.3% for < or = 7 days (P < 0.0001)]. PC use had a lower rate of sepsis than CV use (5.1% vs 15.2%; P < 0.05). Use of intravascular catheters should be balanced between the need for vascular access and the risk of sepsis.

Epidemiology of vancomycin usage at a children's hospital, 1993 through 1995

OBJECTIVE

To describe the epidemiology of vancomycin usage at a children's hospital.

METHODS

A cohort study of patients at Egleston Children's Hospital who were charged for the receipt of vancomycin from October, 1992, through October, 1995, was performed. Data were obtained from pharmacy charge records in the hospital's medical records information system.

RESULTS

During the study period there were 3589 patient hospitalizations in which vancomycin was used. Patients receiving vancomycin were predominantly male (56.6%) and white (62.4%), ranged in age from 0 to 31 (median, 3.8) years and had an average length of stay of 6.0 days. The total number of vancomycin doses was 105,704; the median number of vancomycin doses during each patient hospitalization was 11.0 (range, 1 to 1215). The total charge for vancomycin used was $2,009,746; the median charge for vancomycin per patient was $297.50 (range, $11 to 19,864). The majority (75.7%) of vancomycin doses were given on the hematology (27.6%), neurosurgery (17.9%), cardiothoracic surgery (13.4%), neonatology (9.7%) or general pediatrics (7.1%) services. Overall surgery service patients were significantly more likely to receive vancomycin than were medicine service patients (1267 doses/6221 admissions vs. 1954/19,446; relative risk, 2.03; P < 0.001). During the study period the number of vancomycin doses decreased significantly (P < 0.001).

CONCLUSIONS

This study shows the value of evaluating antimicrobial use through a pharmacy database. Although vancomycin use decreased during the study period, large amounts of vancomycin are still being prescribed primarily on subspecialty service patients. Interventions to reduce vancomycin use should focus on these groups.

Prevention of catheter sepsis: the hub

The prevention of catheter sepsis lies in a sound understanding of the routes through which catheters get contaminated. The catheter hub has been recognized as a portal for microorganisms causing catheter sepsis, particularly in central venous catheters inserted for > 1 wk. Bacteria and fungi may reach the internal surface of the catheter connector during manipulation by hospital staff and then colonize the entire lumen of the catheter. Endoluminal contamination has diagnostic, therapeutic, and preventive implications. Some traditional preventive approaches (site care, subcutaneous cuffs and tunnels, maximal aseptic barriers at the time of catheter insertion, and external antiseptic or antibiotic coating) may fail because they focus solely on the skin as a source of bacteria. Hub-related catheter sepsis can be prevented by aseptic hub manipulation, appropriate junction protection, and by reducing the number of catheter lumens, side ports, three-way stopcocks, and changes of the infusion sets. Needleless systems must be evaluated in terms of their safety in preventing endoluminal contamination. A new disinfecting catheter hub incorporating an antiseptic barrier has been developed and reduced hub-related catheter sepsis by more than 90%. The endoluminal route of intravascular catheter contamination must be taken into account when designing strategies for the diagnosis and prevention of catheter-related sepsis.

Efficacy of a vancomycin solution to prevent bacteremia associated with an indwelling central venous catheter in neutropenic and non-neutropenic cancer patients

We evaluated the efficacy of a vancomycin solution in the prevention of bacteremia caused by vancomycin-sensitive organisms (VSO) in cancer patients with a tunneled central venous catheter (CVC). Eighty-three patients who had a single lumen CVC were randomized to use a heparin solution (25 U/ml) for daily catheter flush with (HepVan) or without (Hep) vancomycin, 25 mcg/ml. Febrile episodes were recorded, and central and peripheral blood cultures were drawn before beginning antibiotic therapy. Patients participated in follow-up to 16,677 catheter days (8,666 Hep and 8,011 HepVan), and 143 febrile episodes were recorded (82 Hep and 61 HepVan). Forty-four episodes of bacteremia occurred, 23 of them due to VSO (16 occurred in the Hep group and 7 in the HepVan group (P = 0.19). VSO bacteremia occurred in 14 neutropenic (absolute neutrophil count < 500 x 10(9)/l) episodes (7 Hep vs. 7 HepVan) and in 9 non-neutropenic episodes (9 Hep vs. O HepVan; P = 0.013). Vancomycin effectively prevented bacteremia by VSO in non-neutropenic patients, supporting the idea that intraluminal colonization of indwelling CVCs contributes to bacteremia only in these patients.