Fifteen-minute consultation: Is this umbilical venous catheter safe to use?

Umbilical venous catheters are widely used in neonatal practice, therefore promoting safe use of such catheters to reduce complications remains a healthcare priority. This report will equip the reader with essential knowledge for successful catheter insertion and maintenance, which is key to better outcomes. Recent advances in safe localisation of catheter tip and the development of a red flag system will enhance the clinician's ability to predict potential complications related to these catheters as they remain in situ.

Therapeutic hypothermia for mild neonatal encephalopathy: a systematic review and meta-analysis.

OBJECTIVES: To examine if therapeutic hypothermia reduces the composite outcome of death, moderate or severe disability at 18 months or more after mild neonatal encephalopathy (NE). DATA SOURCE: MEDLINE, Cochrane database, Scopus and ISI Web of Knowledge databases, using 'hypoxic ischaemic encephalopathy', 'newborn' and 'hypothermia', and 'clinical trials' as medical subject headings and terms. Manual search of the reference lists of all eligible articles and major review articles and additional data from the corresponding authors of selected articles. STUDY SELECTION: Randomised and quasirandomised controlled trials comparing therapeutic hypothermia with usual care. DATA EXTRACTION: Safety and efficacy data extracted independently by two reviewers and analysed. RESULTS: We included the data on 117 babies with mild NE inadvertently recruited to five cooling trials (two whole-body cooling and three selective head cooling) of moderate and severe NE, in the meta-analysis. Adverse outcomes occurred in 11/56 (19.6%) of the cooled babies and 12/61 (19.7%) of the usual care babies (risk ratio 1.11 (95% CIs 0.55 to 2.25)). CONCLUSIONS: Current evidence is insufficient to recommend routine therapeutic hypothermia for babies with mild encephalopathy and significant benefits or harm cannot be excluded.

Therapeutic hypothermia initiated within 6 hours of birth is associated with reduced brain injury on MR biomarkers in mild hypoxic-ischaemic encephalopathy: a non-randomised cohort study.

OBJECTIVE: To examine the effect of therapeutic hypothermia on MR biomarkers and neurodevelopmental outcomes in babies with mild hypoxic-ischaemic encephalopathy (HIE). DESIGN: Non-randomised cohort study. SETTING: Eight tertiary neonatal units in the UK and the USA. PATIENTS: 47 babies with mild HIE on NICHD neurological examination performed within 6 hours after birth. INTERVENTIONS: Whole-body cooling for 72 hours (n=32) or usual care (n=15; of these 5 were cooled for <12 hours). MAIN OUTCOME MEASURES: MRI and MR spectroscopy (MRS) within 2 weeks after birth, and a neurodevelopmental outcome assessment at 2 years. RESULTS: The baseline characteristics in both groups were similar except for lower 10 min Apgar scores (p=0.02) in the cooled babies. Despite this, the mean (SD) thalamic NAA/Cr (1.4 (0.1) vs 1.6 (0.2); p<0.001) and NAA/Cho (0.67 (0.08) vs 0.89 (0.11); p<0.001) ratios from MRS were significantly higher in the cooled group. Cooled babies had lower white matter injury scores than non-cooled babies (p=0.02). Four (27%) non-cooled babies with mild HIE developed seizures after 6 hours of age, while none of the cooled babies developed seizures (p=0.008). Neurodevelopmental outcomes at 2 years were available in 40 (85%) of the babies. Adverse outcomes were seen in 2 (14.3%) non-cooled babies, and none of the cooled babies (p=0.09). CONCLUSIONS: Therapeutic hypothermia may have a neuroprotective effect in babies with mild HIE, as demonstrated by improved MRS biomarkers and reduced white matter injury on MRI. This may warrant further evaluation in adequately powered randomised controlled trials.

Enhanced derivation of osteogenic cells from murine embryonic stem cells after treatment with ionic dissolution products of 58S bioactive sol-gel glass.

Embryonic stem (ES) cells represent a potentially useful cell source for tissue regeneration. Previously, using factors known to enhance differentiation and mineralization of primary osteoblasts, we were able to generate cell populations enriched with osteoblasts from a murine ES cell source. Dexamethasone was a potent inducer of osteoblast differentiation and the timing of stimulation markedly increased the proportion of osteoblast lineage cells. This study examined whether inorganic stimuli derived from bioactive glasses could affect the differentiation of osteoblasts in an ES-cell based system. Previous work has demonstrated the ability of soluble ions released from bioactive glasses undergoing dissolution in vitro to stimulate gene expression characteristic of a mature phenotype in primary osteoblasts. We report here on the potential of soluble extracts prepared from 58S sol-gel bioactive glass to further enhance lineage-specific differentiation in murine ES cells. Differentiation of ES cells into osteogenic cells was characterized by the formation of multilayered, mineralized nodules. These nodules contained cells expressing the transcription factor runx2/cbfa-1, and deposition of osteocalcin in the extracellular matrix was detected by immunostaining. When differentiating cells were placed in an osteoblast maintenance medium supplemented with soluble extracts prepared from bioactive glass powders, we observed increased formation of mineralized nodules (98 +/- 6%, mean +/- SEM) and alkaline phosphatase activity (56 +/- 14%, mean +/- SEM) in a pattern characteristic of osteoblast differentiation. This effect of the glass extracts exhibited dose dependency, with alkaline phosphatase activity and nodule formation increasing with extract concentrations. Compared with medium supplemented with dexamethasone, which had previously been used to enhance osteoblast lineage derivation, the glass extracts were as effective at inducing formation of mineralized nodules by murine ES cells. When glass extracts were used in combination with dexamethasone, a further increase in the number of nodules was observed (110 +/- 16%; cf. 83 +/- 7% for dexamethasone alone). This study demonstrates the capacity of an entirely inorganic material to stimulate differentiation of ES cells toward a lineage with therapeutic potential in tissue-engineering applications.

Time- and concentration-dependent effects of dissolution products of 58S sol-gel bioactive glass on proliferation and differentiation of murine and human osteoblasts.

Bone loss is a significant clinical problem, and treatments utilizing donated graft material are limited. To meet future demands in the healthcare industry, there has been a shift of outlook toward the use of bioactive materials for tissue regeneration. A number of in vivo and in vitro studies have highlighted the potential of the bioactive glass ceramic 45S5 Bioglass as a synthetic regenerative scaffold. The application of sol-gel processing techniques has led to the synthesis of mesoporous bioactive glasses with greater textural and compositional variety. In this study, we evaluated the effects of supplemented tissue culture medium containing up to 203 ppm silica prepared by static soaking of particles of 58S sol-gel bioactive glass (58% SiO(2), 33% CaO, 9% P(2)O(5)) on the in vitro proliferation and differentiation of murine and human primary osteoblasts. These extracts had a higher silica content than those used previously in studies of 45S5 Bioglass, because of the faster rates of ion exchange permitted by the higher surface area-to-volume ratio of mesoporous glass. We found that osteoblasts from both species increased their proliferation in response to the glass-conditioned medium. In addition, the extent to which supplemented medium could alter cell differentiation varied with time in culture. Proliferation induced by supplemented medium paralleled effects induced by treatment with basic fibroblast growth factor, a known mitogenic growth factor for osteoblasts. Bone nodule formation was also increased by exposure to the glass-conditioned medium and this effect was positively correlated with the dose of glass used to prepare the medium. Apoptosis was stimulated by glass-conditioned medium in murine osteoblasts, but inhibited in human osteoblasts. These data demonstrate the bioactive effects of dissolution products derived from sol-gel materials on primary osteoblasts and complements in vivo studies that indicate the suitability of this material as a bone graft substitute.

Bioactivity of gel-glass powders in the CaO-SiO2 system: a comparison with ternary (CaO-P2O5-SiO2) and quaternary glasses (SiO2-CaO-P2O5-Na2O).

Bioactive glasses react chemically with body fluids in a manner that is compatible with the repair processes of the tissues. This results in the formation of an interfacial bond between the glasses and living tissue. Bioactive glasses also stimulate bone-cell proliferation. This behavior is dependent on the chemical composition as well as the surface texture of the glasses. It has been recently reported that gel-derived monolith specimens in the binary SiO2 - CaO are bioactive over a similar molar range of SiO2 content as the previously studied ternary CaO-P2O5-SiO2 system. In this report, the preparation and bioactivity of the binary gel-glass powder with 70 mol % SiO2 is discussed and its bioactivity is compared with the melt-derived 45S5 (quaternary) Bioglass and sol-gel-derived 58S (ternary) bioactive gel-glass compositions. Dissolution kinetic parameters K(1) and K(2) were also computed based on the silicon release for all glass powders. It was shown that the simple two-component SiO2-CaO gel-glass powder is bioactive with comparable dissolution rates as the clinically used melt-derived 45S5 Bioglass powder and extensively studied sol-gel-derived 58S gel-glass powder.