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Peripheral veno-artertial extracorporeal membrane oxygenation (VA-ECMO) is commonly used in the paediatric population for intractable respiratory and cardiac failure. One of the devastating complications of VA-ECMO is severe brain damage due to ischemia or haemorrhage. We describe a case of peripheral cervical VA-ECMO complicated by evolving right cerebral ischemia which was rescued with rapid conversion from peripheral to central VA-ECMO support. Notably, the patient had a complete circle of Willis. Following conversion, we observed complete resolution of neurological symptoms with full functional recovery. [ABSTRACT FROM AUTHOR]

A refined model of fault structure in the active New Madrid Seismic Zone (NMSZ) is presented based on relocated hypocenters and application of a statistical clustering method to determine fault planes. Over 200 earthquakes are recorded in the NMSZ every year, but the three‐dimensional (3‐D) fault structure is difficult to determine because the zone is covered by thick, Mississippi Embayment sediment. The distribution of earthquakes in the NMSZ indicates four major arms of seismicity, suggesting the presence of a northeast‐southwest trending strike‐slip fault system with a major northwest trending, contractional stepover fault. Relocation of 4,131 earthquakes using HypoDD resulted in major improvement in the depiction of fault structure in the NMSZ including three‐dimensional structural variations along the along the Reelfoot fault (RF) and a well‐defined intersection of the Axial and RFs. Optimal Anisotropic Dynamic Clustering analysis of the relocated hypocenters produced a fault model consisting of 12, well resolved planes. The RF is continuous along strike from the northern end to the Ridgely fault, located south of the intersection with the Axial fault (AF). The crosscutting Ridgely fault may serve as a barrier to rupture propagation along the entire fault. The strike‐slip arms of seismicity are well resolved and correspond to near vertical planes. Three planes are resolved in the southern part of the AF and are associated with the Osceola igneous complex. Plain Language Summary: A refined fault model is determined for the active New Madrid seismic zone using earthquakes that occurred from 2000 to 2019. The seismic zone is located in the central United States and poses a hazard to critical infrastructure and numerous population centers. The major faults are the Reelfoot thrust fault and the strike‐slip Axial fault (AF). The first step in constructing the improved fault model involved relocation of the earthquakes to decrease location error. The second step involved fitting planes to the relocated earthquakes under the assumption that the earthquakes cluster along fault segments. The resulting model provides a three‐dimensional representation of the fault structure. A major fault disrupts the southern portion of the Reelfoot fault, making it discontinuous. The northern part of the AF is very well defined. Earthquakes are more scattered along the southern part of the AF, but three fault planes are resolved that are located along the side of a major intrusion. The fault model can be used in studies involving possible rupture length and magnitude of large earthquakes. Key Points: New Madrid Seismic Zone hypocenters for the years 2000–2019 are relocated and have a median relative location error of 65 mPlanes are fit to the relocated hypocenters producing a detailed three‐dimensional model of fault structureThe Reelfoot fault is segmented by the Ridgely fault [ABSTRACT FROM AUTHOR]

Importance: In children undergoing heart surgery, nitric oxide administered into the gas flow of the cardiopulmonary bypass oxygenator may reduce postoperative low cardiac output syndrome, leading to improved recovery and shorter duration of respiratory support. It remains uncertain whether nitric oxide administered into the cardiopulmonary bypass oxygenator improves ventilator-free days (days alive and free from mechanical ventilation).Objective: To determine the effect of nitric oxide applied into the cardiopulmonary bypass oxygenator vs standard care on ventilator-free days in children undergoing surgery for congenital heart disease.Design, Setting, and Participants: Double-blind, multicenter, randomized clinical trial in 6 pediatric cardiac surgical centers in Australia, New Zealand, and the Netherlands. A total of 1371 children younger than 2 years undergoing congenital heart surgery were randomized between July 2017 and April 2021, with 28-day follow-up of the last participant completed on May 24, 2021.Interventions: Patients were assigned to receive nitric oxide at 20 ppm delivered into the cardiopulmonary bypass oxygenator (n = 679) or standard care cardiopulmonary bypass without nitric oxide (n = 685).Main Outcomes and Measures: The primary end point was the number of ventilator-free days from commencement of bypass until day 28. There were 4 secondary end points including a composite of low cardiac output syndrome, extracorporeal life support, or death; length of stay in the intensive care unit; length of stay in the hospital; and postoperative troponin levels.Results: Among 1371 patients who were randomized (mean [SD] age, 21.2 [23.5] weeks; 587 girls [42.8%]), 1364 (99.5%) completed the trial. The number of ventilator-free days did not differ significantly between the nitric oxide and standard care groups, with a median of 26.6 days (IQR, 24.4 to 27.4) vs 26.4 days (IQR, 24.0 to 27.2), respectively, for an absolute difference of -0.01 days (95% CI, -0.25 to 0.22; P = .92). A total of 22.5% of the nitric oxide group and 20.9% of the standard care group developed low cardiac output syndrome within 48 hours, needed extracorporeal support within 48 hours, or died by day 28, for an adjusted odds ratio of 1.12 (95% CI, 0.85 to 1.47). Other secondary outcomes were not significantly different between the groups.Conclusions and Relevance: In children younger than 2 years undergoing cardiopulmonary bypass surgery for congenital heart disease, the use of nitric oxide via cardiopulmonary bypass did not significantly affect the number of ventilator-free days. These findings do not support the use of nitric oxide delivered into the cardiopulmonary bypass oxygenator during heart surgery.Trial Registration: anzctr.org.au Identifier: ACTRN12617000821392. [ABSTRACT FROM AUTHOR]

Purpose: Cardiopulmonary bypass induces an ischaemia-reperfusion injury and systemic inflammatory response, which contributes to low cardiac output syndrome following cardiac surgery. Exogenous nitric oxide during cardiopulmonary bypass has shown potential to ameliorate such injury. We undertook a large randomised controlled trial to investigate the clinical effects of administering nitric oxide to the cardiopulmonary bypass circuit in children.Methods: After written informed consent, children were randomised to receive 20 ppm nitric oxide to the gas inflow of the cardiopulmonary bypass oxygenator, or standard conduct of bypass.Results: 101 children received nitric oxide and developed low cardiac output syndrome less frequently (15 vs. 31 %, p = 0.007) than the 97 children who did not receive nitric oxide. This effect was most marked in children aged less than 6 weeks of age (20 vs. 52 %, p = 0.012) and in those aged 6 weeks to 2 years (6 vs. 24 %, p = 0.026), who also had significantly reduced ICU length of stay (43 vs. 84 h, p = 0.031). Low cardiac output syndrome was less frequent following more complex surgeries if nitric oxide was administered (17 vs. 48 %, p = 0.018). ECMO was used less often in the nitric oxide group (1 vs. 8 %, p = 0.014).Conclusions: Delivery of nitric oxide to the oxygenator gas flow during paediatric cardiopulmonary bypass reduced the incidence of low cardiac output syndrome by varying degrees, according to age group and surgery complexity.Clinical Trial Registration: ACTRN12615001376538. [ABSTRACT FROM AUTHOR]

We develop an automated strategy for discriminating deep microseismic events from shallow ones on the basis of thewaveforms recorded on a limited number of surface receivers. Machinelearning techniques are employed to explore the relationship between event hypocentres and seismic features of the recorded signals in time, frequency and time-frequency domains. We applied the technique to 440 microearthquakes-1.7w <1.29, induced by an underground cavern collapse in the Napoleonville Salt Dome in Bayou Corne, Louisiana. Forty different seismic attributes of whole seismograms including degree of polarization and spectral attributes were measured. A selected set of features was then used to train the system to discriminate between deep and shallow events based on the knowledge gained from existing patterns. The cross-validation test showed that events with depth shallower than 250 m can be discriminated from events with hypocentral depth between 1000 and 2000 m with 88 per cent and 90.7 per cent accuracy using logistic regression and artificial neural network models, respectively. Similar results were obtained using single station seismograms. The results show that the spectral features have the highest correlation to source depth. Spectral centroids and 2-D crosscorrelations in the time-frequency domain are two new seismic features used in this study that showed to be promising measures for seismic event classification. The used machine-learning techniques have application for efficient automatic classification of lowenergy signals recorded at one or more seismic stations. [ABSTRACT FROM AUTHOR]

Objective: The aim of this review is to highlight an emerging problem with anticoagulation-related complications in neonatal and paediatric ECMO, to explore for flaws in the currently recommended anticoagulation management responsible for these problems and to discuss possible strategies mitigating further escalation of the issue. Data Sources: Pertinent neonatal and paediatric literature on the topic of interest and international Extracorporeal Life Support Organisation (ELSO) registry data request. Conclusions: The international ELSO registry data reveals increasing rates of anticoagulation-related complications during neonatal and paediatric ECMO worldwide. The causes are multifactorial and the proposed solution to the problem is to match anticoagulation management to the pathophysiological complexity of haemostasis on ECMO. [ABSTRACT FROM AUTHOR]

This prospective, single-center cohort study aimed to evaluate the hemostatic response during and after Cardiopulmonary Bypass (CPB) surgery in a large cohort of children up to 6 years of age. Blood samples were drawn at eight time points: post-induction of anesthesia, pre-unfractionated heparin (UFH), post-UFH, post-initiation of bypass, pre-protamine, post-protamine, post-chest-closure, and 6 h post-chest-closure. As expected, all measures of the UFH effect increased significantly post-UFH bolus and decreased post-protamine administration. However, thrombin generation remained inhibited compared to baseline values despite the post-UFH reversal by protamine. We also demonstrate that residual UFH effect is not responsible for the ongoing inhibition of thrombin observed post-protamine administration. The significant increase in both free and total tissue factor pathway inhibitor levels during the CPB surgery might contribute to the persistent thrombin generation/endogenous thrombin potential inhibition post-protamine administration. This study makes a significant and novel contribution by investigating the physiological mechanisms behind the degree of thrombin inhibition by UFH and the residual levels of thrombin inhibition that continue despite protamine reversal and provides a new foundation for future interventional studies in the setting of paediatric CPB surgery. [ABSTRACT FROM AUTHOR]

During extracorporeal life support (ECLS), blood is exposed to a myriad of unphysiological factors that can affect outcome. One aspect of this is the sub-atmospheric pressure generated by the ECLS pump and imparted to blood elements along the pump inlet line. This pressure can be measured on the inlet line close to the pump head by adding a connector, or at the venous cannula connection site. We compared the two measurement sites located at both points; between the venous cannula-inlet tubing and inlet tubing-pump, with a range of cannulae and flows. We also investigated the effects on inlet pressure from pump afterload and increasing inlet tubing length. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to investigate ways to attract and retain knowledge workers in a globally successful knowledge city or a city aspiring to become one.Design/methodology/approach – The paper reviews the literature on knowledge work and workers and provides useful recommendations on the fundamentals of how to attract and retain knowledge workers.Findings – The paper sheds light on attracting and retaining knowledge workers that knowledge industries, knowledge-based development and knowledge cities rely on.Originality/value – The paper provides an in-depth discussion on the concepts of knowledge work, knowledge workers and what these workers want when they are not at work. [ABSTRACT FROM AUTHOR]

A 13-year-old girl presented to the emergency department with fatigue, headaches and muscle stiffness after returning from a family camping trip. Within 24 h, she was transferred to ICU with general oedema and low saturations, where she had a cardio-respiratory arrest and was placed on veno-arterial extracorporeal membrane oxygenation (ECMO). The patient was successfully supported with ECMO for profound myocardial dysfunction and haemofiltration for rhabdomyolysis and acute renal failure. Patients who present with profound myocardial dysfunction and myoglobinuria as a consequence of viral infection can be successfully supported with ECMO. [ABSTRACT FROM AUTHOR]

Increasing perioperative haemoglobin level by reducing priming volume and maintaining a safe cardiopulmonary bypass (CPB) system is the aim of every perfusionist. In this study, we have compared the two membrane oxygenators and pump systems used for paediatric bypass at the Royal Children's Hospital on a regular basis since 1988. We looked at all patients who had the Cobe VPCML (Cobe Laboratories, Denver, CO, USA) and Terumo RX-05 (Terumo Corporation, Tokyo, Japan) oxygenators used for flows from 800 mL/min up to the maximum rated flow for the respective oxygenator from January 2002 until March 2004. The VPCML refers to using only the 0.4-m2 section of the oxygenator. The pump systems used were the Stöckert CAPS (Stöckert Instrumente GmbH, Munich, Germany) and Jostra HL 30 (Jostra AB, Lund, Sweden). Changing from the VPCML to the RX-05 resulted in a 37% reduction in priming volume. The introduction of the Jostra HL 30 with a custom-designed mast system reduced the priming volume by another 15%. This change in priming volume allowed a significant increase, from 6 to 34%, in the percentage of patients who received bloodless primes, and for those patients who received blood primes, an increase in haemoglobin (Hb) on bypass from 8.2 to 9.6 g/dL, on average. [ABSTRACT FROM AUTHOR]

The Gambler conjures a world of myth: not as a fiction of human consciousness but as unconscious image-language. Its ambition is to write geography as material subject. In tracing the discourse written in the built environment the text ranges over the analyses of Marx and Freud and into the gestural worlds of Kafka and the blood sports of the ancient Colosseum. It discovers the myth of New Zealand horse racing, written in pictures in the local pub where virtual racing, abstracted from the living world, (dis)plays on the television screen. Here, finally, The Gambler comes to terms with loss. [ABSTRACT FROM AUTHOR]

There has been profound economic and political change in New Zealand in the last decade. It is therefore not surprising that since 1984 there have also been great changes in the urban government of New Zealand. The question posed by this essay is: what do these economic, political and administrative changes mean for urban policy? [ABSTRACT FROM PUBLISHER]