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Shunt-related adverse events are frequent in infants after modified Blalock–Taussig despite use of acetylsalicylic acid prophylaxis. A higher incidence of acetylsalicylic acid-resistance and sub-therapeutic acetylsalicylic acid levels has been reported in infants. We evaluated whether using high-dose acetylsalicylic acid can decrease shunt-related adverse events in infants after modified Blalock–Taussig.
In this single-centre retrospective cohort study, we included infants ⩽1-year-old who underwent modified Blalock–Taussig placement and received acetylsalicylic acid in the ICU. We defined acetylsalicylic acid treatment groups as standard dose (⩽7 mg/kg/day) and high dose (⩾8 mg/kg/day) based on the initiating dose.
There were 34 infants in each group. Both groups were similar in age, gender, cardiac defect type, ICU length of stay, and time interval to second stage or definitive repair. Shunt interventions (18 versus 32%, p=0.16), shunt thrombosis (14 versus 17%, p=0.74), and mortality (9 versus 12%, p=0.65) were not significantly different between groups. On multiple logistic regression analysis, single-ventricle morphology (odds ratio 5.2, 95% confidence interval of 1.2–23, p=0.03) and post-operative red blood cells transfusion ⩾24 hours [odds ratio 15, confidence interval of (3–71), p<0.01] were associated with shunt-related adverse events. High-dose acetylsalicylic acid treatment [odds ratio 2.6, confidence interval of (0.7–10), p=0.16] was not associated with decrease in these events.
High-dose acetylsalicylic acid may not be sufficient in reducing shunt-related adverse events in infants after modified Blalock–Taussig. Post-operative red blood cells transfusion may be a modifiable risk factor for these events. A randomised trial is needed to determine appropriate acetylsalicylic acid dosing in infants with modified Blalock–Taussig.
Chloris spp. are warm-season grasses that outcompete crops for scarce resources throughout Australia. In Queensland, mild winters and increased adoption of conservation tillage practices have led to an increase of this warm-season grass family in winter crops. The objective of this study is to understand whether droplet size (nozzle type) effects herbicide efficacy of summer perennial grasses, as previous research found no effect of droplet size (nozzle type) on herbicide efficacy of winter annual grasses. A study to compare droplet-size (nozzle type) effects on control of windmillgrass and its domesticated relative, rhodesgrass, was conducted at the University of Queensland in Gatton, QLD, Australia. Results showed little difference in dry weight reductions for windmillgrass or rhodesgrass across droplet size (nozzle type). Paraquat applications with the TTI nozzle resulted in significantly lower dry weight reductions compared with other droplet-size sprays (nozzle types) for rhodesgrass. Glyphosate, imazamox plus imazapyr, and clodinafop resulted in commercially acceptable control for both species, regardless of the droplet size (nozzle type) selected, indicating droplet size (nozzle type) has relatively little impact on the efficacy of these herbicides. Proper nozzle selection can result in control of Chloris spp., a hard to control weed species, while reducing the occurrence of spray drift to nearby sensitive areas.
From a symmetric balanced incomplete block design we may construct a derived design by deleting a block and its varieties. But a design with the parameters of a derived design may not be embeddable in a symmetric design. Bhattacharya (1) has such an example with λ = 3 . When λ = 1, the derived design is a finite Euclidean plane and this can always be embedded in a corresponding symmetric design which will be a finite projective plane.
This case report illustrates an unusual case of a dural arteriovenous fistula and an associated encephalocele presenting as otitis media with effusion.
A 53-year-old man presented with right-sided hearing loss and aural fullness of 2 years’ duration. Examination revealed ipsilateral post-auricular pulsatile tenderness. Computed tomography showed transcalvarial channels suggestive of dural arteriovenous fistula. Further magnetic resonance imaging demonstrated the presence of a temporal encephalocele herniating through the tegmen tympani defect, as well as the abnormal vascularity. Angiography confirmed a Cognard type I dural arteriovenous fistula, which is being managed conservatively. Surgical repair of the encephalocele was recommended but declined by the patient.
Dural arteriovenous fistula is an uncommon intracranial vascular malformation rarely seen by otolaryngologists, with pulsatile tinnitus being the usual presentation. To our knowledge, this is the first reported case of dural arteriovenous fistula presenting with conductive hearing loss and otalgia.
Introduction: Recent reports suggest that up to 30% of medical interventions provide no benefit to patients. In a response to ED over-crowding, guidelines commonly exist to guide blood test ordering in patients waiting to see a physician. In many cases, this increases the use of tests without benefiting patients. We describe a quality improvement project designed to reduce the number of laboratory tests considered routine for waiting patients. Methods: A multidisciplinary group reviewed existing symptom-prompted nursing blood test guidelines for serum electrolytes and glucose, renal function tests, liver tests, lipase, toxicological tests and beta Human Chorionic gonadotrophin levels. Order sets were revised with tests eliminated from the routine panels that were not felt to routinely contribute to patient care. The new guidelines were communicated to nursing staff in a series of educational sessions, and the revised guidelines were posted at nursing stations. Physician ordering practice was not changed. A pre-post evaluation compared the period 1 December 2014, - 30 November 2015 with 1 December 2015 - 30 November 2016. Clinical outcomes and patient wait times were not evaluated. Results: The use of tests in these categories decreased 32% between the two periods, at a net saving of $210, 246c. The largest savings came from total protein (73% decrease), Creatine kinase (68%), chloride (64%), glucose (49%), and albumin (47%). Sodium/Potassium testing decreased by only 13%. The only increase in test ordering recorded was AST (3% increase). Conclusion: Simply changing symptom driven order sets resulted in significant savings to the system. In the era of Choosing wisely regular review of lab order sets is indicated. Further study is needed to assess the effect of these changes on patient flow and on clinical outcome.
Pressure ridges impact the mass, energy and momentum budgets of the sea-ice cover and present an obstacle to transportation through ice-infested waters. Quantifying ridge characteristics is important for understanding total sea-ice mass and for improving the representation of sea-ice dynamics in high-resolution models. Multi-sensor measurements collected during annual Operation IceBridge (OIB) airborne surveys of the Arctic provide new opportunities to assess the sea ice at the end of winter. We present a new methodology to derive ridge sail height from high-resolution OIB Digital Mapping System (DMS) visible imagery. We assess the efficacy of the methodology by mapping the full sail height distribution along 12 pressure ridges in the western and central Arctic. Comparisons against coincident Airborne Topographic Mapper (ATM) elevation anomalies are used to demonstrate the methodology and evaluate DMS-derived sail heights. Sail heights and elevation anomalies were correlated at 0.81 or above. On average mean and maximum sail height agreed with ATM elevation to within 0.11 and 0.49 m, respectively. Of the ridges mapped, mean sail height ranged from 0.99 to 2.16 m, while maximum sail height ranged from 2.1 to 4.8 m. DMS also delivered higher sampling along ridge crests than coincident ATM data.
Despite the early optical detection of the Crab pulsar in 1969, optical pulsars have become the poor cousin of the neutron star family. Only five normal pulsars have been observed to pulse in the optical waveband. A further three magnetars/SGRs have been detected in the optical/near IR. Optical pulsars are intrinsically faint with a first order luminosity, predicted by Pacini, to be proportional to P−10, where P is the pulsar’s period. Consequently they require both large telescopes, generally over-subscribed, and long exposure times, generally difficult to get. However optical observations have the benefit that polarisation and spectral observations are possible compared to X-ray and gamma-ray observations where polarisation measurements are limited. Over the next decade the number of optical pulsars should increase as optical detectors approach 100% quantum efficiency and as we move into the era of extremely large telescopes where limiting fluxes will be 30 to 100 times fainter compared to existing optical telescopes.
Auditory implantation into the inner ear is increasingly performed for a variety of indications. Infective complications are rare, but when they occur they can have devastating consequences.
This paper reports two cases where vestibular sequestration of the bony labyrinth developed following implantation into the middle ear.
To the authors' knowledge, these are the first reported cases where vestibular sequestration has resulted from auditory implant surgery. This paper outlines the radiological changes characteristic of this pathology. It also describes the surgical and conservative treatment options for this condition, challenging the previously accepted belief that affected patients always require aggressive surgical intervention.
In this paper we describe a perfect simulation algorithm for the stable M/G/c queue. Sigman (2011) showed how to build a dominated coupling-from-the-past algorithm for perfect simulation of the super-stable M/G/c queue operating under first-come-first-served discipline. Sigman's method used a dominating process provided by the corresponding M/G/1 queue (using Wolff's sample path monotonicity, which applies when service durations are coupled in order of initiation of service). The method exploited the fact that the workload process for the M/G/1 queue remains the same under different queueing disciplines, in particular under the processor sharing discipline, for which a dynamic reversibility property holds. We generalise Sigman's construction to the stable case by comparing the M/G/c queue to a copy run under random assignment. This allows us to produce a naïve perfect simulation algorithm based on running the dominating process back to the time it first empties. We also construct a more efficient algorithm that uses sandwiching by lower and upper processes constructed as coupled M/G/c queues started respectively from the empty state and the state of the M/G/c queue under random assignment. A careful analysis shows that appropriate ordering relationships can still be maintained, so long as service durations continue to be coupled in order of initiation of service. We summarise statistical checks of simulation output, and demonstrate that the mean run-time is finite so long as the second moment of the service duration distribution is finite.
This second edition has been comprehensively updated to reflect current clinical practice and the latest technical developments, including pre-implantation genetic diagnosis, array CGH, QF-PCR, non-invasive prenatal diagnosis and next generation sequencing amongst others. The first section covers basic principles, while the second outlines the more common situations where obstetrics and gynaecology interact with medical genetics. The third section contains real-life clinical case scenarios which have been selected to represent typical problems and to highlight areas which, if mismanaged, could have serious medico-legal consequences. Together with its accompanying website (www.essentialmedgen.com), it provides an invaluable guide to the use and selection of useful online genetic resources. This book is essential reading for candidates preparing for the MRCOG postgraduate examination, and any health professionals requiring a clear understanding of medical genetics and its increasingly frequent uses in obstetrics and gynaecology, where incorrect genetic advice can have serious consequences.