1. |
- Fouhy, Fiona, et al.
(författare)
-
High-throughput sequencing reveals the incomplete, short-term recovery of infant gut microbiota following parenteral antibiotic treatment with ampicillin and gentamicin
- 2012
-
Ingår i: Antimicrobial Agents and Chemotherapy. - Washington, USA : American Society for Microbiology. - 0066-4804 .- 1098-6596. ; 56:11, s. 5811-5820
-
Tidskriftsartikel (refereegranskat)abstract
- The infant gut microbiota undergoes dramatic changes during the first 2 years of life. The acquisition and development of this population can be influenced by numerous factors, and antibiotic treatment has been suggested as one of the most significant. Despite this, however, there have been relatively few studies which have investigated the short-term recovery of the infant gut microbiota following antibiotic treatment. The aim of this study was to use high-throughput sequencing (employing both 16S rRNA and rpoB-specific primers) and quantitative PCR to compare the gut microbiota of nine infants who underwent parenteral antibiotic treatment with ampicillin and gentamicin (within 48 h of birth), 4 and 8 weeks after the conclusion of treatment, relative to that of nine matched healthy controls. The investigation revealed that the gut microbiota of the antibiotic-treated infants had significantly higher proportions of Proteobacteria (P = 0.0049) and significantly lower proportions of Actinobacteria (P = 0.00001) (and the associated genus Bifidobacterium [P = 0.0132]) as well as the genus Lactobacillus (P = 0.0182) than the untreated controls 4 weeks after the cessation of treatment. By week 8, the Proteobacteria levels remained significantly higher in the treated infants (P = 0.0049), but the Actinobacteria, Bifidobacterium, and Lactobacillus levels had recovered and were similar to those in the control samples. Despite this recovery of total Bifidobacterium numbers, rpoB-targeted pyrosequencing revealed that the number of different Bifidobacterium species present in the antibiotic-treated infants was reduced. It is thus apparent that the combined use of ampicillin and gentamicin in early life can have significant effects on the evolution of the infant gut microbiota, the long-term health implications of which remain unknown.
|
|
2. |
- Hyttel-Sorensen, Simon, et al.
(författare)
-
A phase II randomized clinical trial on cerebral near-infrared spectroscopy plus a treatment guideline versus treatment as usual for extremely preterm infants during the first three days of life (SafeBoosC) : study protocol for a randomized controlled trial
- 2013
-
Ingår i: Trials. - : Springer Science and Business Media LLC. - 1745-6215. ; 14, s. 120-
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Every year in Europe about 25,000 infants are born extremely preterm. These infants have a 20% mortality rate, and 25% of survivors have severe long-term cerebral impairment. Preventative measures are key to reduce mortality and morbidity in an extremely preterm population. The primary objective of the SafeBoosC phase II trial is to examine if it is possible to stabilize the cerebral oxygenation of extremely preterm infants during the first 72 hours of life through the application of cerebral near-infrared spectroscopy (NIRS) oximetry and implementation of an clinical treatment guideline based on intervention thresholds of cerebral regional tissue saturation rStO(2). Methods/Design: SafeBoosC is a randomized, blinded, multinational, phase II clinical trial. The inclusion criteria are: neonates born more than 12 weeks preterm; decision to conduct full life support; parental informed consent; and possibility to place the cerebral NIRS oximeter within 3 hours after birth. The infants will be randomized into one of two groups. Both groups will have a cerebral oximeter monitoring device placed within three hours of birth. In the experimental group, the cerebral oxygenation reading will supplement the standard treatment using a predefined treatment guideline. In the control group, the cerebral oxygenation reading will not be visible and the infant will be treated according to the local standards. The primary outcome is the multiplication of the duration and magnitude of rStO(2) values outside the target ranges of 55% to 85%, that is, the 'burden of hypoxia and hyperoxia' expressed in '%hours'. To detect a 50% difference between the experimental and control group in %hours, 166 infants in total must be randomized. Secondary outcomes are mortality at term date, cerebral ultrasound score, and interburst intervals on an amplitude-integrated electroencephalogram at 64 hours of life and explorative outcomes include neurodevelopmental outcome at 2 years corrected age, magnetic resonance imaging at term, blood biomarkers at 6 and 64 hours after birth, and adverse events. Discussion: Cerebral oximetry guided interventions have the potential to improve neurodevelopmental outcome in extremely preterm infants. It is a logical first step to test if it is possible to reduce the burden of hypoxia and hyperoxia.
|
|
3. |
- Hyttel-Sorensen, Simon, et al.
(författare)
-
Clinical use of cerebral oximetry in extremely preterm infants is feasible
- 2013
-
Ingår i: Danish Medical Journal. - 2245-1919. ; 60:1, s. A4533-
-
Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: The research programme Safeguarding the Brains of our smallest Children (SafeBoosC) aims to test the benefits and harms of cerebral near-infrared spectroscopy (NIRS) oximetry in infants born before 28 weeks of gestation. In a phase II trial, infants will be randomised to visible cerebral NIRS oximetry with pre-specified treatment guidelines compared to standard care with blinded NIRS-monitoring. The primary outcome is duration multiplied with the extent outside the normal range of regional tissue oxygen saturation of haemoglobin (rStO(2)) of 55 to 85% in percentage hours (burden). This study was a pilot of the Visible Oximetry Group. MATERIAL AND METHODS: This was an observational study including ten infants. RESULTS: The median gestational age was 26 weeks + three days, and the median start-up time was 133 minutes after delivery. The median recording time was 69.7 hours, mean rStO(2) was 64.2 +/- 4.5%, median burden of hyper- and hypoxia was 30.3% hours (range 2.8-112.3). Clinical staff responded to an out of range value 29 times - only once to values above 85%. In comparison, there were 83 periods of more than ten minutes with an rStO(2) below 55% and four episodes with an rStO(2) above 85%. These periods accounted for 72% of the total hypoxia burden. A total of 18 of the 29 interventions were adjustments of FiO(2) which in 13 of the 18 times resulted in an out-of-range SpO(2). Two infants suffered second-degree burns from the sensor. Five infants died. In all cases, this was unrelated to NIRS monitoring and treatment. CONCLUSION: The intervention of early cerebral NIRS monitoring proved feasible, but prolonged periods of hypoxia went untreated. Thus, a revision of the treatment guideline and an alarm system is required.
|
|
4. |
|
|
5. |
- Pacheco, Andrea, et al.
(författare)
-
Numerical investigation of the influence of the source and detector position for optical measurement of lung volume and oxygen content in preterm infants
- 2022
-
Ingår i: Journal of Biophotonics. - : Wiley. - 1864-063X .- 1864-0648. ; 15:7
-
Tidskriftsartikel (refereegranskat)abstract
- There is an urgent need for improved respiratory surveillance of preterm infants. Gas in scattering media absorption spectroscopy (GASMAS) is emerging as a potential clinical cutaneous monitoring tool of lung functions in neonates. A challenge in the clinical translation of GASMAS is to obtain sufficiently high signal-to-noise ratios in the measurements, since the light attenuation is high in human tissue. Previous GASMAS studies on piglets have shown higher signal quality with an internal source, as more light propagates through the lung and the loss due to scattering and absorption is less. In this article we simulated light propagation with an intratracheal and a dermal source, and investigated the signal quality and lung volume probed. The results suggest that GASMAS has the potential to measure respiratory volumes; and the sensitivity is higher for an intratracheal source which also enables to probe most of the lung.
|
|
6. |
- Pacheco, Andrea, et al.
(författare)
-
Simulation of near-infrared light propagation through the thorax of a neonate : Addressing the optimisation of source and detector positions for measuring lung oxygen content in preterm infants
- 2019
-
Ingår i: Optics in Health Care and Biomedical Optics IX. - : SPIE. - 0277-786X .- 1996-756X. - 9781510630970 ; 11190
-
Konferensbidrag (refereegranskat)abstract
- Gas in scattering media absorption spectroscopy shortly called GASMAS, is a tunable diode laser spectroscopic technique developed for the measurement of gas present in turbid media. The technique relies on the sharp and specific absorption lines of gases which enables sensitive measurements of gas concentrations in the presence of a scattering solid medium with much broader absorption features. The Biophotonics laboratory at Tyndall National Institute (Biophotonics@Tyndall) is currently exploring the clinical translation of GASMAS technology into the respiratory healthcare of neonates. In this study, we use computational tools to assess the potential gain in gas absorption signal. One of the challenges in the development of the GASMAS technique is to obtain a sufficiently good signal in the measurements, as the light attenuation is high in tissue and the lungs are interior organs. To have an estimation of the capabilities and limitations in this specific application of gas spectroscopy, we model the transmission of near infrared (NIR) light in tissue when a 760 nm source and a set of 68 detectors are placed in different locations over the thorax. We segmented the main organs of the thorax from anonymized DICOM images of a neonate. This is followed by the creation of 3D computational models to solve light propagation with the diffusion equation, and the modelling of light propagation through the thorax of an infant including optical properties of lung, heart, arteries, bone, muscle, trachea, fat and skin. Finally, we calculate a map of the optimal light source - detector configurations to obtain the highest signal from oxygen gas imprint in the lungs. The use of computational tools such as NIRFAST Slicer 2.0 for investigation and further understanding of the advantages and limitations of the technology is fundamental. Such simulations enable the recreation of different clinical scenarios and identification of the minimum requirements necessary to further improve the application and develop a bedside clinical device that can potentially be used for continuous monitoring of lung function and control of ventilator settings. The potential capability of measuring non-invasively oxygen, water vapour and carbon dioxide in the lungs, would reduce the need for intubation and extracorporeal membrane oxygenation, as well as lower the incidences of chronic lung disease.
|
|
7. |
- Pellicer, Adelina, et al.
(författare)
-
The SafeBoosC Phase II Randomised Clinical Trial : A Treatment Guideline for Targeted Near-Infrared-Derived Cerebral Tissue Oxygenation versus Standard Treatment in Extremely Preterm Infants
- 2013
-
Ingår i: Neonatology. - : S. Karger AG. - 1661-7800 .- 1661-7819. ; 104:3, s. 171-178
-
Tidskriftsartikel (refereegranskat)abstract
- Near-infrared spectroscopy-derived regional tissue oxygen saturation of haemoglobin (rSto(2)) reflects venous oxygen saturation. If cerebral metabolism is stable, rSto(2) can be used as an estimate of cerebral oxygen delivery. The SafeBoosC phase II randomised clinical trial hypothesises that the burden of hypo- and hyperoxia can be reduced by the combined use of close monitoring of the cerebral rSto(2) and a treatment guideline to correct deviations in rSto(2) outside a predefined target range. Aims: To describe the rationale for and content of this treatment guideline. Methods: Review of the literature and assessment of the quality of evidence and the grade of recommendation for each of the interventions. Results and Conclusions: A clinical intervention algorithm based on the main determinants of cerebral perfusion-oxygenation changes during the first hours after birth was generated. The treatment guideline is presented to assist neonatologists in making decisions in relation to cerebral oximetry readings in preterm infants within the SafeBoosC phase II randomised clinical trial. The evidence grades were relatively low and the guideline cannot be recommended outside a research setting.
|
|
8. |
- Seidler, Anna Lene, et al.
(författare)
-
Systematic review and network meta-analysis with individual participant data on cord management at preterm birth (iCOMP) : Study protocol
- 2020
-
Ingår i: BMJ Open. - : BMJ. - 2044-6055. ; 10:3
-
Forskningsöversikt (refereegranskat)abstract
- Introduction: Timing of cord clamping and other cord management strategies may improve outcomes at preterm birth. However, it is unclear whether benefits apply to all preterm subgroups. Previous and current trials compare various policies, including time-based or physiology-based deferred cord clamping, and cord milking. Individual participant data (IPD) enable exploration of different strategies within subgroups. Network meta-analysis (NMA) enables comparison and ranking of all available interventions using a combination of direct and indirect comparisons. Objectives: (1) To evaluate the effectiveness of cord management strategies for preterm infants on neonatal mortality and morbidity overall and for different participant characteristics using IPD meta-analysis. (2) To evaluate and rank the effect of different cord management strategies for preterm births on mortality and other key outcomes using NMA. Methods and analysis: Systematic searches of Medline, Embase, clinical trial registries, and other sources for all ongoing and completed randomised controlled trials comparing cord management strategies at preterm birth (before 37 weeks' gestation) have been completed up to 13 February 2019, but will be updated regularly to include additional trials. IPD will be sought for all trials; aggregate summary data will be included where IPD are unavailable. First, deferred clamping and cord milking will be compared with immediate clamping in pairwise IPD meta-analyses. The primary outcome will be death prior to hospital discharge. Effect differences will be explored for prespecified participant subgroups. Second, all identified cord management strategies will be compared and ranked in an IPD NMA for the primary outcome and the key secondary outcomes. Treatment effect differences by participant characteristics will be identified. Inconsistency and heterogeneity will be explored. Ethics and dissemination: Ethics approval for this project has been granted by the University of Sydney Human Research Ethics Committee (2018/886). Results will be relevant to clinicians, guideline developers and policy-makers, and will be disseminated via publications, presentations and media releases.
|
|