Culture-Negative Early-Onset Neonatal Sepsis - At the Crossroad Between Efficient Sepsis Care and Antimicrobial Stewardship

Sepsis is a leading cause of mortality and morbidity in neonates. Presenting clinical symptoms are unspecific. Sensitivity and positive predictive value of biomarkers at onset of symptoms are suboptimal. Clinical suspicion therefore frequently leads to empirical antibiotic therapy in uninfected infants. The incidence of culture confirmed early-onset sepsis is rather low, around 0.4-0.8/1000 term infants in high-income countries. Six to 16 times more infants receive therapy for culture-negative sepsis in the absence of a positive blood culture. Thus, culture-negative sepsis contributes to high antibiotic consumption in neonatal units. Antibiotics may be life-saving for the few infants who are truly infected. However, overuse of broad-spectrum antibiotics increases colonization with antibiotic resistant bacteria. Antibiotic therapy also induces perturbations of the non-resilient early life microbiota with potentially long lasting negative impact on the individual's own health. Currently there is no uniform consensus definition for neonatal sepsis. This leads to variations in management. Two factors may reduce the number of culture-negative sepsis cases. First, obtaining adequate blood cultures (0.5-1 mL) at symptom onset is mandatory. Unless there is a strong clinical or biochemical indication to prolong antibiotics physician need to trust the culture results and to stop antibiotics for suspected sepsis within 36-48 h. Secondly, an international robust and pragmatic neonatal sepsis definition is urgently needed. Neonatal sepsis is a dynamic condition. Rigorous evaluation of clinical symptoms ("organ dysfunction") over 36-48 h in combination with appropriately selected biomarkers ("dysregulated host response") may be used to support or refute a sepsis diagnosis.

Growth and neurodevelopment in very preterm infants receiving a high enteral volume-feeding regimen - a population-based cohort study

AIM

The aim of this study is to evaluate a feeding regimen routinely providing >180 ml/kg/d fortified human milk to very preterm infants and impact on in-hospital growth, osteopenia, and neurodevelopment.

METHOD

Retrospective population-based descriptive study of infants <30-week gestation admitted within 24 h of birth and discharged during the 6-year period 2005-2010. Growth and neurodevelopment was assessed until 2 years corrected age, and cerebral palsy up to 4 years corrected age Results: Ninety-nine infants below 30-week gestation were admitted within 24 h of birth during the 6-year period, of which 84 (85%) survived to discharge. Two infants had surgical necrotizing enterocolitis, both survived to 2 years follow up. Seventy-eight infants (mean 27 weeks) had complete growth data until discharge. Full enteral feeds were tolerated after mean 10 d. Average milk volumes were 193 ml/kg/d from 15 to 42 d of life. Rates of weight below 10th centile were 10% at birth and 14% at discharge. Head circumference Z-scores were stable from birth to discharge. Blood values did not indicate osteopenia. Increasing head circumference Z-scores were associated with improved language development.

CONCLUSIONS

This high enteral feeding volume regimen was associated with low rates of in-hospital growth restriction and good head growth. High enteral volume intake seems safe and may improve nutritional status of very preterm infants.

The presence of anaemia negatively influences survival in patients with POLG disease

BACKGROUND

Mitochondria play an important role in iron metabolism and haematopoietic cell homeostasis. Recent studies in mice showed that a mutation in the catalytic subunit of polymerase gamma (POLG) was associated with haematopoietic dysfunction including anaemia. The aim of this study was to analyse the frequency of anaemia in a large cohort of patients with POLG related disease.

METHODS

We conducted a multi-national, retrospective study of 61 patients with confirmed, pathogenic biallelic POLG mutations from six centres, four in Norway and two in the United Kingdom. Clinical, laboratory and genetic data were collected using a structured questionnaire. Anaemia was defined as an abnormally low haemoglobin value adjusted for age and sex. Univariate survival analysis was performed using log-rank test to compare differences in survival time between categories.

RESULTS

Anaemia occurred in 67% (41/61) of patients and in 23% (14/61) it was already present at clinical presentation. The frequency of anaemia in patients with early onset disease including Alpers syndrome and myocerebrohepatopathy spectrum (MCHS) was high (72%) and 35% (8/23) of these had anaemia at presentation. Survival analysis showed that the presence of anaemia was associated with a significantly worse survival (P = 0.004).

CONCLUSION

Our study reveals that anaemia can be a feature of POLG-related disease. Further, we show that its presence is associated with significantly worse prognosis either because anaemia itself is impacting survival or because it reflects the presence of more serious disease. In either case, our data suggests anaemia is a marker for negative prognosis.

Volume-targeted versus pressure-limited ventilation in neonates

BACKGROUND

Damage caused by lung overdistension (volutrauma) has been implicated in the development of bronchopulmonary dysplasia (BPD). Modern neonatal ventilation modes can target a set tidal volume as an alternative to traditional pressure-limited ventilation (PLV) using a fixed inflation pressure. Volume-targeted ventilation (VTV) aims to produce a more stable tidal volume in order to reduce lung damage and stabilise the partial pressure of carbon dioxide (pCO2).

OBJECTIVES

To determine whether VTV compared with PLV leads to reduced rates of death and death or BPD in newborn infants and to determine whether use of VTV affected outcomes including air leak, cranial ultrasound findings and neurodevelopment.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2016, Issue 12), MEDLINE via PubMed (1966 to 13 January 2017), Embase (1980 to 13 January 2017) and CINAHL (1982 to 13 January 2017). We also searched clinical trials databases, conference proceedings and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. We contacted the principal investigators of studies to obtain supplementary information.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing VTV versus PLV in infants of less than 44 weeks' postmenstrual age and reporting clinically relevant outcomes.

DATA COLLECTION AND ANALYSIS

We assessed risk of bias for each trial using Cochrane methodology. We evaluated quality of evidence for each outcome using GRADE criteria. We tabulated mortality, rates of BPD, short-term clinical outcomes and long-term developmental outcomes.

STATISTICS

for categorical outcomes, we calculated typical estimates for risk ratios (RR), risk differences (RD) and number needed to treat for an additional beneficial outcome (NNTB). For continuous variables, we calculated typical estimates for mean differences (MD). We used 95% confidence intervals (CI) and assumed a fixed-effect model for meta-analysis.

MAIN RESULTS

Twenty randomised trials met our inclusion criteria; 16 parallel trials (977 infants) and four cross-over trials (88 infants). No studies were blinded and the quality of evidence for outcomes assessed varied from moderate to low.We found no difference in the primary outcome, death before hospital discharge, between VTV modes versus PLV modes (typical RR 0.75, 95% CI 0.53 to 1.07; low quality evidence). However, there was moderate quality evidence that the use of VTV modes resulted in a reduction in the primary outcome, death or BPD at 36 weeks' gestation (typical RR 0.73, 95% CI 0.59 to 0.89; typical NNTB 8, 95% CI 5 to 20) and the following secondary outcomes: rates of pneumothorax (typical RR 0.52, 95% CI 0.31 to 0.87; typical NNTB 20, 95% CI 11 to 100), mean days of mechanical ventilation (MD -1.35 days, 95% CI -1.83 to -0.86), rates of hypocarbia (typical RR 0.49, 95% CI 0.33 to 0.72; typical NNTB 3, 95% CI 2 to 5), rates of grade 3 or 4 intraventricular haemorrhage (typical RR 0.53, 95% CI 0.37 to 0.77; typical NNTB 11, 95% CI 7 to 25) and the combined outcome of periventricular leukomalacia with or without grade 3 or 4 intraventricular haemorrhage (typical RR 0.47, 95% CI 0.27 to 0.80; typical NNTB 11, 95% CI 7 to 33). VTV modes were not associated with any increased adverse outcomes.

AUTHORS' CONCLUSIONS

Infants ventilated using VTV modes had reduced rates of death or BPD, pneumothoraces, hypocarbia, severe cranial ultrasound pathologies and duration of ventilation compared with infants ventilated using PLV modes. Further studies are needed to identify whether VTV modes improve neurodevelopmental outcomes and to compare and refine VTV strategies.

Staphylococcus aureus enterotoxin sensitization is associated with allergic poly-sensitization and allergic multimorbidity in adolescents

BACKGROUND

Staphylococcus aureus (S. aureus) carriage and sensitization to S. aureus enterotoxins (SEs) have been associated with allergic diseases. From the Tromsø Study Fit Futures 2, we have previously shown an association between S. aureus carriage and severe allergic disease and allergic multimorbidity. However, the role of S. aureus carriage and SE sensitization on allergic multimorbidity and allergic sensitization is unclear.

OBJECTIVE

To study associations of both nasal S. aureus carriage and SE sensitization to allergic disease and allergic sensitization.

METHODS

A cross-sectional study of a school-based cohort in late adolescence (aged 18-19 years: The Tromsø Study Fit Futures 2). Self-reported allergic diseases were assessed using the Mechanisms of the Development of ALLergy questionnaire (MeDALL). Participants were tested for nasal S. aureus carriage, serum total IgE and specific IgE to SEs, and food and inhalant allergens.

RESULTS

A total of 868 participants were studied. Sensitization to at least one food or inhalant allergen was found in 319 of 765 (41.7%), and to at least one SE in 173 of 656 (26.2%) participants. SE sensitization, but not S. aureus carriage, was associated with poly-sensitization to food and inhalant allergens. SE-sensitized participants had higher median specific IgE to inhalant allergens (41.4 kU_A /L, IQR 10.1-118.4) compared to non-SE-sensitized participants (18.0 kU_A /L, IQR 5.5-48.6, P=.004), but not to food allergens. SE sensitization was associated with allergic multimorbidity.

CONCLUSION

Sensitization to SEs may play a role in the development of allergen poly-sensitization and allergic multimorbidity.

Coagulase-negative staphylococci in Southern Brazil: looking toward its high diversity

INTRODUCTION

Coagulase-negative staphylococci (CoNS) are the most prevalent pathogens in nosocomial infections and may serve as a reservoir of mobile genetic elements such as the staphylococcal cassette chromosome mec (SCCmec) encoding methicillin resistance. Molecular characterization of SCCmec types combined with advanced molecular typing techniques may provide essential information for understanding the evolution and epidemiology of CoNS infections. We therefore aimed to investigate the SCCmec distribution, multidrug-resistance (MDR), and biofilm formation in CoNS blood culture isolates from a hospital in Southern Brazil.

METHODS

We analyzed 136 CoNS blood culture isolates obtained during 2002-2004 from patients admitted to a tertiary care hospital in Brazil. SCCmec types I to V were determined using multiplex PCR. The clonal relationship of Staphylococcus epidermidis was determined using pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Molecular epidemiological data were interpreted along with data on biofilm formation, presence of the icaD gene, and MDR.

RESULTS

The most prevalent species were S. epidermidis, Staphylococcus haemolyticus, and Staphylococcus hominis harboring mainly SCCmec types II, III, and V. Overall, the presence of multiple SCCmec was associated with non-MDR, except for S. epidermidis. S. epidermidis isolates showed a high prevalence of icaD, but had low phenotypic biofilm formation. PFGE and MLST revealed high genetic diversity in the S. epidermidis population.

CONCLUSIONS

Our results suggest a major shift in SCCmec types within a short period and reveal a different behavior of S. epidermidis with regard to the association between the presence of multiple SCCmec types and MDR profile.

Neonatal Morbidity and 1-Year Survival of Extremely Preterm Infants

OBJECTIVE

To determine 1-year survival and major neonatal morbidities (intracranial hemorrhage grade >2, cystic periventricular leukomalacia, retinopathy of prematurity grade >2, necrotizing enterocolitis, severe bronchopulmonary dysplasia) among extremely preterm infants in Norway in 2013-2014, and to compare the results to the first Norwegian Extreme Prematurity Study 1999-2000 and similar contemporary European population-based studies.

METHODS

Population-based study of all infants born at 22 through 26 weeks' gestation in Norway in 2013-2014. Prospectively collected data were obtained by linking data in the Norwegian Neonatal Network to the Medical Birth Registry of Norway.

RESULTS

Of 420 infants (incidence 3.5 per 1000 births), 145 were stillborn (34.5%), 275 were live-born (82.3% of the 334 fetuses alive at admission for obstetrical care), and 251 (91.3% of live-born infants) were admitted to a neonatal unit. The survival among live-born infants was 18% at 22 weeks, 29% at 23 weeks, 56% at 24 weeks, 84% at 25 weeks and 90% at 26 weeks (for each week increment in gestational age: odds ratio 3.3; 95% confidence interval, 2.4-4.4). Among infants surviving to 1 year of age, major neonatal morbidity was diagnosed in 55%. Decreasing gestational age was moderately associated with rates of major morbidity (odds ratio 1.6; 95% confidence interval, 1.2-2.2).

CONCLUSIONS

Compared to the previous 1999-2000 cohort, the rate of stillbirth before admission to an obstetrical unit increased, whereas the survival rate among live born infants was similar in our 2013-2014 cohort. Neonatal morbidity rates remain high among extremely preterm infants.

Management of early-onset neonatal sepsis differs in the north and south of Scandinavia

AIM

This study compared the management and outcomes of early-onset neonatal sepsis (EONS) in two tertiary neonatal units in Denmark and Norway.

METHODS

We retrospectively studied all infants diagnosed with EONS between April 2010 and March 2013 and managed at Odense University Hospital, Denmark, and the University Hospital of North Norway, Norway. Clinical and laboratory data were collected from patient records.

RESULTS

We identified 137 EONS cases in Denmark and 101 in Norway. There were 35 culture-confirmed EONS cases: 16% of the Danish cases and 13% of the Norwegian cases. Staphylococcus aureus was the most frequently detected pathogen in 11 cases (31%), followed by Group B streptococci in nine (26%) and Escherichia coli in six (17%). In 85% of the 238 cases, the empiric therapy comprised gentamicin and a beta-lactam, namely ampicillin in Denmark and benzylpenicillin in Norway. Patients with positive blood cultures had higher C-reactive protein levels than patients with negative blood cultures and higher sepsis-attributable mortality. Lumbar punctures were performed more frequently in Denmark.

CONCLUSION

There were marginal differences in the management of EONS between units in Denmark and Norway, mainly in their choice of antibiotics and the use of lumbar punctures. Staphylococcus aureus was the most common pathogen.

Allergic disease and Staphylococcus aureus carriage in adolescents in the Arctic region of Norway

BACKGROUND

Allergic diseases are common chronic diseases in children and adolescents, but limited epidemiological data are available during transition into adulthood. Nasal Staphylococcus aureus carriage has been linked to increased prevalence of allergic disease. The objective of this study was to define the prevalence of allergic diseases in adolescents above the Arctic Circle in Northern Norway and to study the associations of S. aureus carriage with allergic diseases.

METHODS

A school-based cohort in late adolescence (18-19 years) was invited to participate in a cross-sectional study on lifestyle and health, and 868 attended (71.9%). Self-reported allergic disease and severity of eczema were assessed by Mechanisms of the Development of Allergy and Patient-Oriented Eczema Measure questionnaires. Participants were tested with spirometry and exhaled nitric oxide (FeNO) and swabbed for bacterial culture from nose and eczematous skin.

RESULTS

We found asthma, eczema, allergic rhinitis (AR), and nasal S. aureus carriage among 11.9%, 10.4%, 26.0%, and 51.3% of the participants, respectively, and 10.2% had allergic multimorbidity. Lifetime prevalence for any allergic disease was 45.1%. Reduced lung function and increased FeNO were found in 11.6% and 22.1% in participants with asthma, respectively. Nasal S. aureus carriage was associated with eczema, severe asthma, and severe AR. FeNO > 25 ppb was associated with both asthma and nasal S. aureus carriage.

CONCLUSION

Asthma, eczema, and AR are common among adolescents above the Arctic Circle in Norway. Allergic disease is associated with S. aureus carriage, but its role in the pathogenesis and severity is not established.

Antimicrobial susceptibility and body site distribution of community isolates of coagulase-negative staphylococci

The primary aim of this study was to determine antimicrobial resistance in coagulase-negative staphylococci (CoNS) from healthy adults in the community. Healthy adults (n = 114) were swabbed on six body sites; both armpits, both knee pits and both sides of the groin. Species determination was performed using Matrix Assisted Laser Desorption Ionization - Time of Flight (MALDI-TOF) and susceptibility testing for 11 relevant antimicrobials was performed by the disc diffusion method and minimal inhibitory concentration gradient test. In total, 693 CoNS isolates were identified. Susceptibility testing was done on 386 isolates; one CoNS from each species found on each participant from the different body sites. The prevalence of antimicrobial resistance in the CoNS isolates were; erythromycin (24.6%), fusidic acid (19.9%), tetracycline (11.4%), clindamycin (7.8%), gentamicin (6.2%) and cefoxitin (4.1%). Multidrug resistance was observed in 5.2% of the isolates. Staphylococcus epidermidis and S. hominis were the first and second most prevalent species on all three body sites. We conclude that CoNS isolates from healthy adults in the community have a much lower prevalence of antimicrobial resistance than reported in nosocomial CoNS isolates. Still, we believe that levels of resistance in community CoNS should be monitored as the consumption of antimicrobials in primary care in Norway is increasing.

Newborn manikin study shows that physicians often fail to detect correct lung compliance when using a self-inflating bag

AIM

Recognising changes in lung compliance can help clinicians to adjust initial inflations during resuscitation at birth. We examined whether physicians sensed low and normal compliance with a self-inflating bag before and after an educational intervention that used a manikin connected to a newborn lung simulator.

METHODS

We asked 43 physicians with neonatal duties to perform two low compliance ventilation attempts and two normal-compliance ventilation attempts in a randomised order at baseline and after the educational intervention, with 34 taking part in a retest three months later.

RESULTS

The physicians correctly recognised low and normal compliance in 71% and 66% of the ventilations at baseline, 80% and 66% of the ventilations after the intervention and 74% and 81% at retest. Correct recognition of normal compliance improved from baseline to retest (p = 0.04). Ventilations in low- vs normal-compliance settings resulted in lower tidal volumes (4.4 vs 23.0 mL, p < 0.001), lower ventilation rates (42 vs 51, p < 0.001) and higher peak inflating pressure (35.2 vs 31.4 cmH2 O, p < 0.001).

CONCLUSION

Around one in four physicians failed to recognise correct compliance levels when using a self-inflating bag and showed limited improvement after an educational intervention. Ventilations in a low-compliance setting resulted in suboptimal ventilation.

Single Sustained Inflation followed by Ventilation Leads to Rapid Cardiorespiratory Recovery but Causes Cerebral Vascular Leakage in Asphyxiated Near-Term Lambs

Background

A sustained inflation (SI) rapidly restores cardiac function in asphyxic, bradycardic newborns but its effects on cerebral haemodynamics and brain injury are unknown. We determined the effect of different SI strategies on carotid blood flow (CaBF) and cerebral vascular integrity in asphyxiated near-term lambs.

Methods

Lambs were instrumented and delivered at 139 ± 2 d gestation and asphyxia was induced by delaying ventilation onset. Lambs were randomised to receive 5 consecutive 3 s SI (multiple SI; n = 6), a single 30 s SI (single SI; n = 6) or conventional ventilation (no SI; n = 6). Ventilation continued for 30 min in all lambs while CaBF and respiratory function parameters were recorded. Brains were assessed for gross histopathology and vascular leakage.

Results

CaBF increased more rapidly and to a greater extent during a single SI (p = 0.01), which then decreased below both other groups by 10 min, due to a higher cerebral oxygen delivery (p = 0.01). Blood brain barrier disruption was increased in single SI lambs as indicated by increased numbers of blood vessel profiles with plasma protein extravasation (p = 0.001) in the cerebral cortex. There were no differences in CaBF or cerebral oxygen delivery between the multiple SI and no SI lambs.

Conclusions

Ventilation with an initial single 30 s SI improves circulatory recovery, but is associated with greater disruption of blood brain barrier function, which may exacerbate brain injury suffered by asphyxiated newborns. This injury may occur as a direct result of the initial SI or to the higher tidal volumes delivered during subsequent ventilation.

How doctors learn and perform sustained inflations with a self-inflating bag: a manikin study with a newborn lung simulator

AIM

Sustained inflations during initial resuscitation may help a depressed infant make a more efficient transition to air-filled lungs. This study examined whether doctors could perform sustained inflations with a self-inflating bag in high and low compliance settings and with an open or blocked pressure-relief valve.

METHODS

We asked 43 doctors to carry out sustained inflations for more than 5-sec in a manikin connected to a newborn lung simulator with randomised compliance settings. Tidal volume, inflation time, peak and mean inflating pressure were measured, and 34 were retested 3 months later.

RESULTS

The majority of the doctors - 72% in the initial study and 62% in the retest - managed sustained inflations within three ventilation attempts, irrespective of lung compliance setting and years of work experience. Using a blocked pressure-relief valve produced higher tidal volume (27.8 versus 22.6 mL, p < 0.001), inflation time (8.9 versus 8.1 sec, p = 0.025), peak inflating pressure (34.0 versus 28.0 cmH2O; p = 0.012) and mean inflating pressure (28.1 versus 22.8 cmH2O; p < 0.001).

CONCLUSION

The majority of doctors could deliver sustained inflation with a self-inflating bag in a newborn lung simulator for more than 5-sec. Using a blocked pressure-relief valve resulted in higher inflation time, tidal volume and inflation pressure.

Circulatory responses to asphyxia differ if the asphyxia occurs in utero or ex utero in near-term lambs

Background

A cornerstone of neonatal resuscitation teaching suggests that a rapid vagal-mediated bradycardia is one of the first signs of perinatal compromise. As this understanding is based primarily on fetal studies, we investigated whether the heart rate and blood pressure response to total asphyxia is influenced by whether the animal is in utero or ex utero.

Methods

Fetal sheep were instrumented at ∼139 days of gestation and then asphyxiated by umbilical cord occlusion until mean arterial blood pressure decreased to ∼20 mmHg. Lambs were either completely submerged in amniotic fluid (in utero; n = 8) throughout the asphyxia or were delivered and then remained ex utero (ex utero; n = 8) throughout the asphyxia. Heart rate and arterial blood pressure were continuously recorded.

Results

Heart rate was higher in ex utero lambs than in utero lambs. Heart rates in in utero lambs rapidly decreased, while heart rates in ex utero lambs initially increased following cord occlusion (for ∼1.5 min) before they started to decrease. Mean arterial pressure initially increased then decreased in both groups.

Conclusions

Heart rate response to asphyxia was markedly different depending upon whether the lamb was in utero or ex utero. This indicates that the cardiovascular responses to perinatal asphyxia are significantly influenced by the newborn's local environment. As such, based solely on heart rate, the stage and severity of a perinatal asphyxic event may not be as accurate as previously assumed.

Whole-genome sequencing reveals clonal expansion of multiresistant Staphylococcus haemolyticus in European hospitals

OBJECTIVES

Staphylococcus haemolyticus is an emerging cause of nosocomial infections, primarily affecting immunocompromised patients. A comparative genomic analysis was performed on clinical S. haemolyticus isolates to investigate their genetic relationship and explore the coding sequences with respect to antimicrobial resistance determinants and putative hospital adaptation.

METHODS

Whole-genome sequencing was performed on 134 isolates of S. haemolyticus from geographically diverse origins (Belgium, 2; Germany, 10; Japan, 13; Norway, 54; Spain, 2; Switzerland, 43; UK, 9; USA, 1). Each genome was individually assembled. Protein coding sequences (CDSs) were predicted and homologous genes were categorized into three types: Type I, core genes, homologues present in all strains; Type II, unique core genes, homologues shared by only a subgroup of strains; and Type III, unique genes, strain-specific CDSs. The phylogenetic relationship between the isolates was built from variable sites in the form of single nucleotide polymorphisms (SNPs) in the core genome and used to construct a maximum likelihood phylogeny.

RESULTS

SNPs in the genome core regions divided the isolates into one major group of 126 isolates and one minor group of isolates with highly diverse genomes. The major group was further subdivided into seven clades (A-G), of which four (A-D) encompassed isolates only from Europe. Antimicrobial multiresistance was observed in 77.7% of the collection. High levels of homologous recombination were detected in genes involved in adherence, staphylococcal host adaptation and bacterial cell communication.

CONCLUSIONS

The presence of several successful and highly resistant clones underlines the adaptive potential of this opportunistic pathogen.

Colonisation and interaction between S. epidermidis and S. aureus in the nose and throat of healthy adolescents

Nasal colonisation with Staphylococcus aureus is a risk factor for developing nosocomial infections. It has been reported that S. epidermidis may produce a serine protease (Esp) inhibiting S. aureus biofilm formation and nasal colonisation. We aimed to analyse the correlation between S. aureus nasal and/or throat carriage and co-colonisation with S. epidermidis strains carrying esp, and the inhibitory effects of S. epidermidis culture supernatants on S. aureus biofilm formation and growth. We obtained 114 S. epidermidis isolates from the nose and 74 S. aureus from the nose and/or throat of healthy adolescents. S. aureus biofilm formation was analysed in a microtitre plate assay and the prevalence of ica, encoding biofilm formation, and esp was analysed with polymerase chain reaction (PCR). Inhibitory effects of S. epidermidis culture supernatants on S. aureus biofilm formation and growth was analysed in vitro. esp prevalence and expression was correlated with inhibitory effects. We detected biofilm formation in 45/74 (61%) S. aureus strains. The ica operon was more prevalent in isolates colonising the nose (12/15; 80%) versus isolates colonising the throat only (8/46; 17%). Almost two-thirds of S. epidermidis culture supernatants displayed high (≥ 50%) S. aureus biofilm inhibitory activity, without affecting growth. We found no correlation between the level of inhibitory activity and S. aureus colonisation. esp was ubiquitous in S. epidermidis, but esp expression did not correlate with biofilm inhibitory activity. S. epidermidis culture supernatants inhibit S. aureus biofilm formation, but do not affect bacterial growth. esp expression was not correlated with the inhibitory effects observed.

Patient comfort during treatment with heated humidified high flow nasal cannulae versus nasal continuous positive airway pressure: a randomised cross-over trial

OBJECTIVE

To compare patient comfort in preterm infants treated with heated humidified high flow nasal cannulae (HHHFNC) versus nasal continuous positive airway pressure (NCPAP).

DESIGN

Randomised cross-over trial (2×24 h).

SETTING

Single tertiary neonatal unit.

PATIENTS

20 infants less than 34 weeks postmenstrual age treated with NCPAP due to mild respiratory illness.

INTERVENTIONS

After parental consent, infants were randomised to 24 h of treatment with NCPAP or HHHFNC followed by 24 h of the alternate therapy.

MAIN OUTCOME MEASURES

Primary outcome was patient comfort assessed by the EDIN (neonatal pain and discomfort) scale. Secondary outcomes were respiratory parameters (respiratory rate, FiO2, SpO2, TcPCO2), ambient noise, salivary cortisol and parental assessments of their child.

RESULTS

We found no differences between HHHFNC and NCPAP in mean cumulative EDIN score (10.7 vs 11.1, p=0.25) or ambient noise (70 vs 74 dBa, p=0.18). Parents assessed HHHFNC treatment as significantly better in the three domains, 1) child satisfied, 2) parental contact and interaction and 3) possibility to take part in care. Mean respiratory rate over 24 h was lower during HHHFNC than CPAP (41 vs 46, p=0.001). Other respiratory parameters were similar.

CONCLUSIONS

Using EDIN scale, we found no difference in patient comfort with HHHFNC versus NCPAP. However, parents preferred HHHFNC, and during HHHFNC respiratory rate was lower than during NCPAP.

CLINICALTRIALSGOV, NUMBER

NCT01526226.

Umbilical cord clamping at birth--practice in Norwegian maternity wards

BACKGROUND

The timing and practice used for umbilical cord clamping of neonates are controversial internationally as well as in Norway. We therefore wished to investigate routines and practices for umbilical cord clamping of neonates in Norway.

MATERIAL AND METHOD

A web-based questionnaire was sent to heads of departments of all maternity wards in Norway (n = 52). They were asked about their practice with regard to umbilical cord clamping of neonates and whether written routines had been prepared for this purpose. We defined early umbilical cord clamping as immediate or within 30 seconds and late clamping as ≥ 1 minute or not until pulsation in the umbilical cord had ceased.

RESULTS

Fifty (96%) of the maternity institutions returned a completed questionnaire. Twelve institutions (24%) reported to clamp the umbilical cord of full-term neonates early, and 38 (76%) reported to practise late clamping. Nineteen maternity wards (38%) followed written routines for umbilical cord clamping of full-term neonates, and among these, early umbilical cord clamping was practised in nine (47%). In the 31 maternity wards that had no written routines, early umbilical cord clamping was practised in three (10%). Twenty-seven of the maternity wards reported that the child is placed on the maternal abdomen before clamping of the umbilical cord, 14 reported that the child commonly is held below the introitus before umbilical cord clamping, and the rest did not report any consistent practice.

INTERPRETATION

There is wide variation in the practice for umbilical cord clamping in Norwegian maternity wards, many of which have no written guidelines. We argue that national guidelines for umbilical cord clamping of neonates should be established.