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In this study, a new hybrid PET/MRI method for quantitative regional cerebral blood flow (rCBF) measurements in healthy newborn infants was assessed and the low values of rCBF in white matter previously obtained by arterial spin labeling (ASL) were tested. Four healthy full-term newborn subjects were scanned in a PET/MRI scanner during natural sleep after median intravenous injection of 14 MBq 15O-water. Regional CBF was quantified using a one-tissue-compartment model employing an image-derived input function (IDIF) from the left ventricle. PET rCBF showed the highest values in the thalami, mesencephalon and brain stem and the lowest in cortex and unmyelinated white matter. The average global CBF was 17.8 ml/100 g/min. The average frontal and occipital unmyelinated white matter CBF was 10.3 ml/100 g/min and average thalamic CBF 31.3 ml/100 g/min. The average white matter/thalamic ratio CBF was 0.36, significantly higher than previous ASL data. The rCBF ASL measurements were all unsuccessful primarily owing to subject movement. In this study, we demonstrated for the first time, a minimally invasive PET/MRI method using low activity 15O-water PET for quantitative rCBF assessment in unsedated healthy newborn infants and found a white/grey matter CBF ratio similar to that of the adult human brain.

Cerebral near-infrared spectroscopy (NIRS) oximetry may help clinicians to improve patient treatment. However, the application of NIRS oximeters is increasingly causing confusion to the users due to the inconsistency of tissue oxygen haemoglobin saturation (StO2) readings provided by different oximeters. To establish a comparability of oximeters, in our study we performed simultaneous measurements on the liquid phantom mimicking properties of neonatal heads and compared the tested device to a reference NIRS oximeter (OxiplexTS). We evaluated the NIRS oximeters FORE-SIGHT, NIRO and SenSmart, and reproduced previous results with the INVOS and OxyPrem v1.3 oximeters. In general, linear relationships of the StO2 values with respect to the reference were obtained. Device specific hypoxic and hyperoxic thresholds (as used in the SafeBoosC study, www.safeboosc.eu) and a table allowing for conversion of StO2 values are provided.

AIM: Necrotising enterocolitis contributes considerably to the mortality of preterm infants, but most questions remain unsolved after decades of extensive research. This Danish study investigated the validity of necrotising enterocolitis diagnoses at discharge according to Bell's staging system.METHODS: We conducted a retrospective single-centre cohort study of 714 preterm infants with a gestational age of less than 30 weeks born in 2006-2013. The infants were diagnosed with necrotising enterocolitis according to Bell's stages 2-3 at discharge and in retrospect by an expert panel, which served as our gold standard.RESULTS: The sensitivity of necrotising enterocolitis diagnosed at discharge was 0.72-0.75 depending on whether spontaneous intestinal perforation was included as necrotising enterocolitis or not. The positive predictive value of the diagnosis was 0.49-0.61. The incidence was significantly higher when diagnosed at discharge than when diagnosed by the expert panel (11.1 versus 9.0%, p = 0.03). The mortality rate for infants who were underdiagnosed at discharge was 50.0%, and it was 25.8% for infants who were overdiagnosed (p = 0.10).CONCLUSION: We found poor validity for the discharge diagnosis of necrotising enterocolitis. In future, a better way of defining the disease is needed for large-scale epidemiologic research.

AIM: This study investigated whether a correlation existed between surgical findings during the first laparotomy for necrotising enterocolitis (NEC) and death and, or, disease progression.METHODS: We included infants admitted within one day of birth to our tertiary neonatal department at Rigshospitalet, Denmark, from 2006 to 2015, who underwent a laparotomy for acute NEC. They were classified according to the locality and extent of intestinal necrosis by a paediatric surgeon, based on the surgical findings. We correlated the surgical findings with postoperative outcomes, namely death and, or, progression of NEC.RESULTS: The first laparotomy showed that 48 infants had NEC, including 21 who demonstrated postoperative progression. Of these, six died before undergoing another laparotomy and 14 of the 15 infants who underwent relaparotomy also died. There was a significant association between surgical findings and NEC-related mortality (p = 0.03). The association between surgical findings and the progression of NEC was also significant (p < 0.0001).CONCLUSION: Surgical findings during laparotomy for NEC were strongly correlated with mortality, which was close to 100% after relaparotomy. Considering the discouraging outcome, further studies should focus on alternative surgical approaches, such as proximal diverting jejunostomy and the clip and drop technique for the treatment of severe NEC.

The interpretation of cerebral tissue oxygen saturation values (StO2) in clinical settings is currently complicated by the use of different near-infrared spectrophotometry (NIRS) devices producing different StO2 values for the same oxygenation due to differences in the algorithms and technical aspects. The aim was to investigate the effect of changes in scattering and absorption on the StO2 of different NIRS devices in a liquid optical phantom. We compared three continuous-wave (CW) with a frequency domain (FD) NIRS device. Responsiveness to oxygenation changes was only slightly altered by different intralipid (IL) concentrations. However, alterations in haematocrit (htc) showed a strong effect: increased htc led to a 20-35% increased response of all CW devices compared to the FD device, probably due to differences in algorithms regarding the water concentration.

Item does not contain fulltext, The American Academy of Pediatrics recently released its new Technical Report and Policy Statement on male circumcision, concluding that current evidence indicates that the health benefits of newborn male circumcision outweigh the risks. The technical report is based on the scrutiny of a large number of complex scientific articles. Therefore, while striving for objectivity, the conclusions drawn by the 8 task force members reflect what these individual physicians perceived as trustworthy evidence. Seen from the outside, cultural bias reflecting the normality of nontherapeutic male circumcision in the United States seems obvious, and the report's conclusions are different from those reached by physicians in other parts of the Western world, including Europe, Canada, and Australia. In this commentary, a different view is presented by non-US-based physicians and representatives of general medical associations and societies for pediatrics, pediatric surgery, and pediatric urology in Northern Europe. To these authors, only 1 of the arguments put forward by the American Academy of Pediatrics has some theoretical relevance in relation to infant male circumcision; namely, the possible protection against urinary tract infections in infant boys, which can easily be treated with antibiotics without tissue loss. The other claimed health benefits, including protection against HIV/AIDS, genital herpes, genital warts, and penile cancer, are questionable, weak, and likely to have little public health relevance in a Western context, and they do not represent compelling reasons for surgery before boys are old enough to decide for themselves.

Premature birth increases a child's risk of cerebral palsy and death. The aim of this work is to investigate the association between treatment with magnesium sulphate during premature deliveries and infants' cerebral palsy and mortality through a meta-analysis of observational studies. A comprehensive search of the Cochrane Library, EMBASE and the PubMed database from their inceptions to 1 October, 2010 using the keywords 'magnesium sulphate, children/infant/pre-term/premature and cerebral palsy/mortality/morbidity/adverse effects/outcome' identified 11 reports of observational studies. Two authors working independently extracted the data. A meta-analysis of the data found an association between magnesium sulphate treatment and a significantly reduced risk of mortality (RR 0.73; 95% CI 0.61-0.89) and cerebral palsy (OR 0.64; 95% CI 0.47-0.89). Antenatal treatment with magnesium sulphate during premature deliveries seems to be associated with health benefits for the infants. The effective dose and timing, however, is not defined and given the lack of mechanistic understanding of the effect of MgSO(4), a reasonable alternative is a large-scale pragmatic clinical trial.

Several instruments implementing spatially resolved near-infrared spectroscopy (NIRS) to monitor tissue oxygenation are now approved for clinical use. The neonatal brain is readily assessible by NIRS and neurodevelopmental impairment is common in children who were in need of intensive care during the neonatal period. It is likely that an important part of the burden of this handicap is due to brain injury induced by hypoxia-ischaemia during intensive care. In particular, this is true for infants born extremely preterm. Thus, monitoring of cerebral oxygenation has considerable potential benefit in this group. The benefit, however, should be weighed against the disturbance to the infant, against the limitations imposed on clinical care and against costs. The ultimate way of demonstrating the 'added value' is by a randomized controlled trial. Cerebral oximetry must reduce the risk of a clinically relevant endpoint, such as death or neurodevelopmental handicap. We estimate that such a trial should recruit about 4000 infants to have the power to detect a reduction in brain injury by one-fifth. This illustrates the formidable task of providing first-grade evidence for the clinical value of diagnostic methods. Is it a window of opportunity for the establishment of a rational basis before another technology is added to an already overly complex newborn intensive care?

1 maart 2010, Item does not contain fulltext, The most important cerebrovascular injuries in newborn infants, particularly in preterm infants, are cerebral haemorrhage and ischemic injury. The typical cerebral vascular anatomy and the disturbance of cerebral haemodynamics play important roles in the pathophysiology. The term 'cerebral haemodynamics' includes cerebral blood flow (CBF), cerebral blood flow velocity, and cerebral blood volume (CBV). Therapy aimed at changing vascular anatomy is not available. Therefore, prevention of disturbances in CBF and CBV is pivotal. However, continuous monitoring of CBF and CBV is still unavailable for clinical use. Tissue oxygenation may be used as a surrogate for CBF, although precision is still questionable. General knowledge of the regulation of CBF and CBV is important. Although this knowledge is still incomplete, especially regarding autoregulation and the exact role of CBV, it is still useful. Using it even without knowing the exact level of CBF and CBV, it is possible to aim to keep CBF and CBV stable. Future research should focus on development of monitoring tools, gaining more insight in neonatal cerebral autoregulation, and demonstrating clinical benefits of a 'cerebral perfusion-oriented' therapy.

Coherence between spontaneous fluctuations in arterial blood pressure (ABP) and the cerebral near-infrared spectroscopy signal can detect cerebral autoregulation. Because reliable measurement depends on signals with high signal-to-noise ratio, we hypothesized that coherence is more precisely determined when fluctuations in ABP are large rather than small. Therefore, we investigated whether adjusting for variability in ABP (variabilityABP) improves precision. We examined the impact of variabilityABP within the power spectrum in each measurement and between repeated measurements in preterm infants. We also examined total monitoring time required to discriminate among infants with a simulation study. We studied 22 preterm infants (GA<30) yielding 215 10-min measurements. Surprisingly, adjusting for variabilityABP within the power spectrum did not improve the precision. However, adjusting for the variabilityABP among repeated measurements (i.e., weighting measurements with high variabilityABP in favor of those with low) improved the precision. The evidence of drift in individual infants was weak. Minimum monitoring time needed to discriminate among infants was 1.3–3.7 h. Coherence analysis in low frequencies (0.04–0.1 Hz) had higher precision and statistically more power than in very low frequencies (0.003–0.04 Hz). In conclusion, a reliable detection of cerebral autoregulation takes hours and the precision is improved by adjusting for variabilityABP between repeated measurements.

Udgivelsesdato: 2009