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BACKGROUND AND OBJECTIVES: Data from clinical trials support the use of continuous positive airway pressure (CPAP) for initial respiratory management in preterm infants, but there is concern regarding the potential failure of CPAP support. We aimed to examine the incidence and explore the outcomes of CPAP failure in Australian and New Zealand Neonatal Network data from 2007 to 2013. METHODS: Data from inborn preterm infants managed on CPAP from the outset were analyzed in 2 gestational age ranges (25-28 and 29-32 completed weeks). Outcomes after CPAP failure (need for intubation <72 hours) were compared with those succeeding on CPAP using adjusted odds ratios (AORs). RESULTS: Within the cohort of 19 103 infants, 11 684 were initially managed on CPAP. Failure of CPAP occurred in 863 (43%) of 1989 infants commencing on CPAP at 25-28 weeks' gestation and 2061 (21%) of 9695 at 29-32 weeks. CPAP failure was associated with a substantially higher rate of pneumothorax, and a heightened risk of death, bronchopulmonary dysplasia (BPD) and other morbidities compared with those managed successfully on CPAP. The incidence of death or BPD was also increased: (25-28 weeks: 39% vs 20%, AOR 2.30, 99% confidence interval 1.71-3.10; 29-32 weeks: 12% vs 3.1%, AOR 3.62 [2.76-4.74]). The CPAP failure group had longer durations of respiratory support and hospitalization. CONCLUSIONS: CPAP failure in preterm infants is associated with increased risk of mortality and major morbidities, including BPD. Strategies to promote successful CPAP application should be pursued vigorously. [ABSTRACT FROM AUTHOR]

Aim: The study aims to compare three commonly used neonatal resuscitation devices, the Laerdal self-inflating bag with a positive end expiratory pressure (PEEP) valve, a T-piece resuscitator (T-piece) and a flow-inflating bag to provide peak inflation pressure (PIP) and PEEP. Methods: Participants were asked to use each device to give positive pressure ventilation to a modified neonatal mannequin via a face mask to achieve 40-60 inflations per minute, aiming for a PIP/PEEP of 30/5 cm H2O. A manometer was visible to participants with each device. PIP, PEEP, percentage leak at the face mask and expired tidal volume were measured using a hot-wire anemometer. We analysed 20 inflations from each participant for each device. Results: Fifty participants provided PIP and PEEP with each device. The T-piece was the most accurate and consistent. The flow-inflating bag had the most variation. The leak was lowest with the self-inflating bag and PEEP and highest with the flow-inflating bag, but all had wide variation. Conclusion: Each device was able to provide PIP and PEEP when used appropriately. When compared with other resuscitation devices, the T-piece provided the most accurate and consistent PIP and PEEP. [ABSTRACT FROM AUTHOR]

We report a patient with continuously recurring hemolytic-uremic syndrome due to factor H deficiency. First at the age of 3 months he showed signs of hemolytic anemia, thrombocytopenia and renal insufficiency, often recurring concomitantly with respiratory tract infections, despite weekly to twice weekly plasma substitution (20 ml/kg body weight). Now at the age of 3.5 years glomerular filtration rate is approximately 50 ml/min/1.73 m[sup 2] and psychomotoric development is normal. Since factor H is mainly synthesized in the liver, hepatic transplantation has been proposed as curative treatment. Before justification of liver transplantation as the ultimate treatment for these patients, an international registry should be developed to optimize and standardize therapeutic alternatives. [ABSTRACT FROM AUTHOR]

Hemolytic-uremic syndrome (HUS) is mainly associated with foodborne infections by Shiga toxin-producing Escherichia coli (STEC). From January 1997 through December 2000, 394 children with HUS were evaluated in a prospective multicenter surveillance study in Germany and Austria (incidences, 0.7/100,000 and 0.4/100,000 children <15 years old, respectively). Blood leukocytosis was associated with increased detection of STEC in stool cultures (P .01) and a more severe disease course. Risk of death was associated with cerebral involvement (P < .01). Most strikingly, non-O157:H7 STEC were detected in 43% of stool cultures of patients with HUS: 026 was detected in 15%, sorbitol-fermenting O157:H- in 10%, O145 in 9%, O103 in 3%, and O111 in 43%. Patients with O157:H7 serotypes required dialysis for a longer time and had bloody diarrhea detected more frequently, compared with patients with nonO157:H7 serotypes (P < .05). This large study in children with HUS underlines the rising importance of non-O157:H7 serotypes, and, despite increased public awareness, the number of patients remained unchanged. [ABSTRACT FROM AUTHOR]

Background: Some national resuscitation guidelines advocate using sustained initial inflations (2-3 s) for babies requiring resuscitation. Inflation times ≥10 s have been used for preterm infants. Objectives: This study examines the ability of operators of varying experience to provide a sustained inflation using three different manual ventilation devices. Methods: We compared a self-inflating bag, a flow-inflating bag and a pressure-limited T-piece device. Fifty clinical staff members from five professional groups gave a sustained inflation with a target peak pressure of 30 cm H2O and target duration of 10 s to an internal leak-free manikin. We measured peak inflating pressure (PIP) and mean inflating pressure (MIP) during the sustained inflation, and the duration of inflating pressure (IP) >20 and 25 cm H2O. Results: Median (IQR) duration of IP >25 cm H2O was: self-inflating bag 2.5 s (0.8-5.7), flow-inflating bag 10.6 s (8.4-12.9) and the T-piece 10.7 s (8.9-11.9). There was a weak correlation between experience using a self-inflating bag and longer inflation times (R = 0.290, p = 0.041). When compared with the T-piece, the flow-inflating bag had lower mean MIP (27.0 ± 1.8 vs. 28.8 ± 2.0 cm H2O) and higher mean PIP (32.3 ± 3.7 vs. 29.8 ± 1.8 cm H2O). There were no differences in performance between operator groups. Conclusion: The T-piece provided consistent PIP during a single 10 s sustained inflation with less variation in pressure compared with the flow-inflating bag. Sustained inflations >3 s were difficult to achieve with a self-inflating bag. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Staphylococcal α-toxin forms heptameric pores that render membranes permeable for monovalent cations. The pore is formed by an amphipathic βbarrel encompassing amino acid residues 118-140 of each subunit of the oligomer. Human fibroblasts are susceptible to α-toxin but are able to repair the membrane lesions. Thereby, toxin oligomers remain embedded in the plasma membrane and exposed to the extracellular medium. In this study, we sought to detect structural changes occurring in the poreforming sequence during lesion repair. Single cysteine substitution mutants were labelled with the environmentally sensitive fluorochrome acrylodan and, after mixing with wild-type toxin, incorporated into hybrid heptamers on fibroblast membranes. Formation of the lipid-inserted β-barrel was accompanied by characteristic fluorescence emission shifts. After lesion repair, the environment of the residues at the outer surface of the β-barrel remained unchanged, indicating continued contact with lipids. However, the labelled residues oriented towards the channel lumen underwent a green to blue shift in fluorescence, indicating reduced exposure to water. Pore closure proceeded in the presence of calmodulin inhibitors and of microtubule disruptors; however, it was prevented by cytochalasin D and by inhibitors of lipid metabolism. Our findings reveal the existence of a novel mechanism of membrane repair that may consist in constriction of the inserted proteinaceous pore within the lipid bilayer. [ABSTRACT FROM AUTHOR]