bluuebunny/crossref_metadata_2025 huggingface dataset:
Insight into enhanced field-effect mobility of 4H-SiC MOSFET with Ba incorporation studied by Hall effect measurements
Authors: Fujita Eigo , Sometani Mitsuru , Hatakeyama Tetsuo , Harada Shinsuke , Yano Hiroshi , Hosoi Takuji , Shimura Takayoshi , Watanabe Heiji
Published: August 2018

Improved performance in 4H-SiC metal-oxide-semiconductor field-effect transistors (MOSFETs) by incorporating Ba into insulator/SiC interfaces was investigated by using a combination of the Hall effect and split capacitance-voltage measurements. It was found that a moderate annealing temperature causes negligible metal-enhanced oxidation, which is rather beneficial for increments in field-effect mobility (μFE) of the FETs together with suppressed surface roughness of the gate oxides. The combined method revealed that, while severe μFE degradation in SiC-MOSFETs is caused by a reduction of effective mobile carriers due to carrier trapping at the SiO2/SiC interfaces, Ba incorporation into the interface significantly increases mobile carrier density with greater impact than the widely-used nitrided interfaces.
Short time helium annealing for solution-processed amorphous indium-gallium-zinc-oxide thin-film transistors
Authors: Lee Seung-Un , Jeong Jaewook
Published: August 2018

In this paper, the short time annealing effects on the solution-processed amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) were studied as a function of different ambient conditions. By comparing the effects of various inert gases as He, Ar, and N2 on the a-IGZO TFTs, it was found that the He-annealed TFTs prepared over a short annealing time of 30 min performed comparably to the 120 min N2-annealed samples. Similarities in the temperature dependency of the electrical characteristics of the He-annealed TFTs and the N2-annealed TFTs were also observed. These similarities are attributed to the high thermal speed of the He atoms, leading to a fast annealing effect. X-ray photoelectron spectroscopy results indicate that the superior performance of the short time He-annealed TFT does not originate from the difference in chemical residue such as OH-, but from the difference in active layer density.
Microstructure of Cu2S nanoprecipitates and its effect on electrical and thermal properties in thermoelectric Cu2Zn0.2Sn0.8S3 ceramics
Authors: Li Chao , Shen Yawei , Song Haili , Wang Yifeng , Chen Shiyou , Qi Ruijuan , Cheng Yan , Duan Chun-Gang , Huang Rong
Published: August 2018

The microstructures of Cu2Zn0.2Sn0.8S3 ceramics with high electrical conductivity and low thermal conductivity were investigated by a combination of selected area electron diffraction, high-resolution transmission electron microscopy, X-ray energy dispersive spectroscopy and atom force microscopy techniques. The plate-like tetragonal metastable Cu2S nanoprecipitates with elongated and equiaxed shape were embedded in a distinctive mosaic nanostructure with roughly 10 nm wide facetted domains (fully disordered phase) surrounded by a ∼5 nm wide connective phase (a semi-ordered monoclinic-Cu4ZnSn2S7 phase) were observed. These metastable Cu2S nanoprecipitates show clear orientation relationships with the matrix that the plates align with three crystal axes of cubic lattice. A combination of conductive atomic force microscopy and Kelvin probe force microscopy reveals that the nanoprecipitates have higher electrical conductivity than the matrix due to the higher carrier density, which can inject into the matrix and enhance the total electric conductivity of the sample. Furthermore, a mechanism of phonon scattering is proposed based on the effects of the occupation disorder of Cu atoms in Cu2S nanoprecipitates, coherent heterointerfaces between Cu2S and matrix, and the extended strain field in the matrix regions adjacent to the Cu2S nanoprecipitates.
Thermal stress distribution in a laser array structure selectively grown on V-groove-patterned silicon
Authors: Yin Haiying , Wang Jun , Yang Zeyuan , Cheng Zhuo , Wang Wei , Huang Yongqing , Ren Xiaomin
Published: August 2018

The thermal stress due to the thermal expansion mismatch could induce crystallographic defects such as buckling and cracking and degrade device performance. In this paper, the thermal stress distribution in a laser array structure selectively grown on V-groove-patterned Si substrates was investigated by two-dimension finite-element method. Surprisingly, unexpected results are observed that the top of the InGaAs active layer and the most region of the InP cap layer are in compression, which is far different from the thermal stress distribution in planar structures. Two mechanisms have been proposed and modeled to explain the difference—(i) the width of uncoalesced layers is smaller than that of the Si substrate, which causes thermal stress to change in epitaxial layers, and (ii) thermal stress in the InGaAs and InP layers is affected by the V-groove structure. The results show that whether or not the epitaxial layers are coalesced has significant effect on the thermal stress distribution. The effect of the height of the V-groove, the height and the width of the SiO2 mask on the thermal stress distribution was also studied. It is found that the height of V-groove and the height of SiO2 mask play a critical role in the stress distribution. These findings are useful for the optimal designs for the laser array and provide an important step towards the realization of photonic integration circuits on silicon.
Activated sludge foaming: can phage therapy provide a control strategy?
Authors: Petrovski Steve , Seviour Robert
Published: August 2018

Foaming in activated sludge systems is a global problem leading to environmental, cosmetic and operational problems. Proliferation of filamentous hydrophobic bacteria (including the Mycolata) are responsible for the stabilisation of foams. Currently no reliable methods exist to control these. Reducing the levels of the filamentous bacteria with bacteriophages below the threshold supporting foaming is an attractive approach to control their impact. We have isolated 88 bacteriophages that target members of the foaming Mycolata. These double stranded DNA phages have been characterised and are currently being assessed for their performance as antifoam agents.
Intraspecific variation in space use of a coastal population of lace monitors (Varanus varius)
Authors: Lei Juan , Booth David T.
Published: August 2018

The lace monitor (Varanus varius) is a carnivorous scavenger that inhabits lowland forests and coastlines throughout south-eastern Australia. Here we used global positioning system (GPS) devices to remotely monitor adult lace monitor behaviour across two summer seasons in a coastal habitat adjacent to a sea turtle nesting beach at Wreck Rock, Queensland, Australia. GPS tracking showed that lace monitors spent most of their time in woodland habitat away from the seafront dune areas. Both adult males and females occupied relatively large home ranges (0.005 to 1.467 km2 calculated by the Kernel Brownian Bridge method) and individual home ranges overlapped each other to a large extent. The space use patterns of individual lace monitors could be classified as ‘linear’ or ‘clumped’, indicating plasticity in this species’ movement behaviour. Because lace monitors rarely visited the frontal dune area where sea turtles nest, they do not pose a significant threat to sea turtle nests.
The Impact of Vaccination and Prior Exposure on Stool Shedding of Salmonella Typhi and Salmonella Paratyphi in 6 Controlled Human Infection Studies
Authors: Gibani Malick M , Voysey Merryn , Jin Celina , Jones Claire , Thomaides-Brears Helena , Jones Elizabeth , Baker Philip , Morgan Marcus , Simmons Alison , Gordon Melita A , Cerundolo Vincenzo , Pitzer Virginia E , Angus Brian , Levine Myron M , Darton Thomas C , Pollard Andrew J
Published: August 2018

Six Salmonella Typhi or Paratyphi human challenge studies were conducted, and daily stool cultures performed. Vi-containing vaccines reduced bacterial shedding, Ty21a or an experimental vaccine did not. Higher Vi immunoglobulin G titers were associated with reduced shedding.
Relationship between extralaryngeal endoscopic findings, proton pump inhibitor (PPI) response, and pH measures in suspected laryngopharyngeal reflux
Authors: Agrawal N , Yadlapati R , Shabeeb N , Price C PE , Lidder A , Shintani-Smith S , Bové M , Pandolfino J , Tan B
Published: August 2018

Laryngopharyngeal reflux (LPR) is a clinical entity diagnosed by history laryngoscopic findings that has a variable response to empiric proton-pump inhibitor (PPI) therapy. While the reflux finding score (RFS), an endoscopic scoring scheme, has been advanced as a measure of LPR, it has not been externally validated against symptom severity in practice. Extralaryngeal pharyngeal endoscopic findings may have diagnostic utility but remain underexplored. This study assesses the correlation between extralaryngeal findings and (1) 24-hour oropharyngeal pH & (2) PPI response in patients with suspected LPR. Subjects presented to a tertiary care center with laryngeal symptoms ≥1 month and reflux symptom index (RSI) ≥13. Following baseline questionnaires, laryngoscopy, and a 24-hour oropharyngeal pH probe study, subjects were prescribed 8–12 week omeprazole trials. Baseline endoscopic findings were scored in a blinded fashion using the RFS and extralaryngeal score criteria, summatively the ‘ELS.’ PPI response was defined as ≥50% improvement in RSI. Thirty-three subjects with flexible endoscopic recordings completed baseline and follow-up questionnaires. The cohort's baseline mean RSI was 23.0 ± 7.2 with a ΔRSI = 9.8 after PPI therapy. The baseline RFS score averaged 5.3 ± 2.7. 45% of our subjects was found to be PPI responsive. The Cohen's kappa for the ELS but not the RFS was significant. There were no significant differences between the RFS (P = 0.10) or ELS (P = 0.07) for PPI responders & nonresponders. Oropharyngeal pH measures did not correlate with the RFS or ELS. In conclusion, endoscopic scores of laryngeal and extralaryngeal findings did not predict PPI response or oropharyngeal acid exposure in suspected LPR.
Challenging violence against women: a Scottish critical health literacy initiative
Authors: Fage-Butler Antoinette Mary
Published: August 2018

Violence against women constitutes a significant public health problem affecting an estimated 35% of women worldwide (WHO, 2013); the scale of the problem and its ongoing intransigence indicate the need for critical and transformative approaches that confront the cultures that support gender violence and lead to change. The present paper analyses a program run in Scottish primary schools for 10–12 year olds called RESPECT that was successful in making pupils alert to and critical of gendering norms and practices. Analysis reveals that the teaching plans and activities of RESPECT are highly consistent with a critical pedagogical approach (Freire, 2005; Matthews, 2014), and indicates the value of combining the theoretical approaches of critical pedagogy, feminism and critical health literacy in public health campaign materials aimed at challenging the cultural bases of gender violence in ways that promote health in an educational setting.
Comprehending practitioners’ assessments of community-led total sanitation
Authors: Ficek František , Novotný Josef
Published: August 2018

Around 2.3 billion people in developing countries still lack access to improved sanitation facilities and almost one billion practice open defecation (OD). The Community-Led Total Sanitation (CLTS) has recently become a particularly popular approach used in more than 60 countries. CLTS is a behavior-change approach that aims to ignite community action and make OD socially unacceptable without providing any external financial or material support to individual households. CLTS is sometimes perceived as a revolutionary approach that has proven to be highly cost-effective in abolishing OD. However, it has been criticized for its use of unethical practices and questioned with respect to the sustainability of its outcomes and the limited health benefits it can generate. Based on semi-structured interviews with development workers experienced in the implementation of CLTS in 14 different countries, this paper seeks to examine practical views on the issues surrounding this approach. We found that despite acknowledging some of the controversies and the possibly limited sustainability of results, CLTS is generally considered an effective and satisfactory tool for improving sanitation conditions. Practitioners first of all accentuate the normative importance of the elimination of OD attained through CLTS without weighting on (the absence of) evidence on the longer term effects or impacts on health. However, a need for various modifications of CLTS according to local social and natural environments was strongly expressed, including changes that go against the core principles of CLTS like no subsidies and no technical assistance principles.
ODE observers for DAE systems
Authors: Berger Thomas , Reis Timo
Published: August 2018

We consider linear time-invariant differential-algebraic systems which are not necessarily regular. The following question is addressed: when does an (asymptotic) observer which is realized by an ordinary differential equation (ODE) system exist? In our main result we characterize the existence of such observers by means of a simple criterion on the system matrices. To be specific, we show that an ODE observer exists if, and only if, the completely controllable part of the system is impulse observable. Extending the observer design from earlier works we provide a procedure for the construction of (asymptotic) ODE observers.
Sovereign Bond Contracts: Flaws in the Public Data?
Authors: Kropp Andrea E , Weidemaier W Mark C , Gulati Mitu
Published: August 2018

Commercial databases now make available to paying clients information about the legal terms in sovereign loan contracts. This information is important to academic researchers, to policy institutions such as the International Monetary Fund, and to investors and other market actors. For a random sample of 10 countries, the authors compare this data to a hand-coded sample of bond terms. They find significant error rates in the commercial databases, which vary significantly by country and by the legal term at issue. In some cases, they document error rates well over 75 per cent. They also describe important limitations in the data, especially the use of binary coding schemes that obscure important differences in the rights conferred by different sovereign loan contracts.
General Principles for Preoperative Planning and Microsurgical Treatment of Pediatric Brain Arteriovenous Malformations: 2-Dimensional Operative Video
Authors: Penn David L , Wu Kyle C , Presswood Kayla R , Riordan Coleman P , Scott R Michael , Smith Edward R
Published: August 2018

Children with arteriovenous malformations (AVMs) are at cumulative, life-long risk of debilitating and fatal intracranial hemorrhage, especially with syndromes such as hereditary hemorrhagic telangiectasia. Cerebral angiography is the gold standard for diagnosis and allows simultaneous adjunctive embolization limiting radiation and contrast exposure and intraoperative blood loss, important in pediatric patients with low blood volume. Microsurgical resection of low-grade AVMs offers cure with minimal morbidity. The plasticity of the pediatric brain may allow resection of AVMs near eloquent regions. Multidisciplinary care offers the best outcomes in these cases. Discussion of the operative plan with all team members at the start of surgery is carried out. Confirmation that blood products are present and that the microscope, additional suction, and surgical clips are available is performed. A generous craniotomy is created, adequately exposing the lesion. The dura is carefully opened to avoid injury to draining veins. Circumferential dissection and isolation of the AVM is performed, coagulating small arterial feeders, dissecting to the lesion's apex to coagulate, and divide major deep feeders. Once all feeders have been obliterated, venous drainage is disconnected. Indocyanine green distinguishes arterial feeders from arterialized veins and confirms complete resection. Since 2008, all of our patients undergo perioperative angiography in our dedicated suite, greatly improving resection rates. Strict blood pressure control and close neurological monitoring in the intensive care unit is performed postoperatively. In conclusion, microsurgical resection of AVMs can be performed safely with low rates of morbidity. Protocols for preoperative evaluation and planning appear to improve outcomes.

 Anonymous video is permitted when done without identifying patient related information.
Interhemispheric Approaches to Arteriovenous Malformations: 3-Dimensional Operative Video
Authors: Agarwal Vijay , Barrow Daniel L
Published: August 2018

We present 2 illustrative cases of interhemispheric approaches to right sided arteriovenous malformations (AVMs). The first patient is a healthy 54-yr-old female who presented with left-sided hearing loss and pulsatile tinnitus, and was neurologically intact. Imaging demonstrated a right sided interhemispheric AVM, fed by the anterior cerebral artery with superficial venous drainage to the superior sagittal sinus. The AVM was thought to be asymptomatic and the patient chose to have her AVM treated surgically to eliminate future risk of hemorrhage. We elected to approach this lesion via a contralateral interhemispheric approach to avoid retraction of the right hemisphere. Intraoperative angiogram demonstrated complete obliteration of the malformation and the patient was neurologically intact postoperatively. The second patient is a 41-yr-old healthy male who presented with progressive bifrontal headaches and was also neurologically intact. Imaging revealed a right interhemispheric AVM fed by the anterior cerebral artery and with superficial venous drainage to the superior sagittal sinus. Although the patient's headaches may have been related, the patient's decision to undergo surgical resection was primarily to eliminate future risk of hemorrhage. The difference with this patient was that imaging revealed the presence of two draining veins on the left side that would potentially be injured via a contralateral approach. As a result, we elected to approach this lesion ipsilaterally. Intraoperative angiogram showed complete obliteration of the malformation with intact venous drainage, and the patient was neurologically intact postoperatively. Contralateral vs ipsilateral interhemispheric approaches are compared and contrasted.
Integrating Social Media Into an Online Academic Program
Authors: Smith Shelly , Buchanan Holly
Published: August 2018

There is a noticeable gap in the literature regarding the programmatic integration of social media into health sciences education. Networked participatory scholarship theory supports the use of social media in higher education; associated benefits include promoting student engagement and real-time dissemination. This article describes the integration of social media use in a graduate online doctoral nursing program; specifically, blogging, microblogging, and ePortfolio integration are presented. The purpose is to improve students' utilization of social media as a professional tool.
HIV update
Authors: Shannon Mary
Published: August 2018

Although there have been many advances in the past 30 years, HIV remains a healthcare concern throughout the world. Nurses play a critical role in educating patients about HIV transmission, treatment, and prevention, as well as identifying at-risk patients for preexposure prophylaxis.
Evaluating Adherence to Guideline-Based Quality Indicators for Postpartum Hemorrhage Care in the Netherlands Using Video Analysis
Authors: Woiski Mallory , de Visser Suzan , van Vugt Helena , Dijkman Anneke , Schuitemaker Nico , van Meir Claudia , Middeldorp Johanna , Huisjes Anjoke , Mol Ben W. , Molkenboer Jan , Moonen-Delarue Desiree , Oudijk Martijn , van Rheenen-Flach Leonie , Rijnders Robert , Pernet Paula , Porath Martina , de Wit Sander , Grol Richard , Scheepers Hubertina , Hermens Rosella
Published: August 2018

OBJECTIVE:

To assess adherence to the national postpartum hemorrhage guideline and Managing Obstetric Emergencies and Trauma course instructions and its determinants in the Netherlands.

METHODS:

A prospective observational multicenter study in 16 Dutch hospitals analyzing data from medical records of 398 women at high risk for postpartum hemorrhage, of which 293 were supplemented with data from prospective video recordings. Adherence to guideline-based quality indicators for prevention, management, and organization of postpartum hemorrhage care was measured. Indicators for prevention and management of postpartum hemorrhage were categorized according to the amount of blood loss (less than 500, greater than 500, greater than 1,000, and greater than 2,000 mL).

RESULTS:

Overall, a lack of adherence was observed, particularly for the actions to be undertaken with blood loss greater than 1,000 mL (69 patients). Actions were not or only taken in a later stage when the blood loss had already increased to greater than 2,000 mL (21 patients). In almost 41% (n=119/293) of the deliveries, no active management was performed, and in almost 80% (n=89/112), vital signs were not monitored (blood loss greater than 500 mL) or monitored too late with respect to blood loss. The video recordings showed that in general the actual care given was considerably underreported in medical records. Postpartum hemorrhage care in the hospitals was well organized. Fifteen hospitals had a local postpartum hemorrhage protocol, and in 12 hospitals, team trainings were organized. Regarding the determinants, high-risk patient identification and type of hospital (university vs nonuniversity hospital) were mostly associated with better adherence.

CONCLUSION:

This study showed low adherence to the guideline-based quality indicators, indicating a problem with Dutch quality care. The unique video observations provided additional, valuable information at which level improvement can be made. A tailor-made implementation strategy to improve quality of postpartum hemorrhage care has been developed.

CLINICAL TRIAL REGISTRATION:

ClinicalTrials.gov, NCT00928863.
Maternal and Fetal Risk Associated With Assisted Reproductive Technology
Authors: Kawwass Jennifer F. , Badell Martina L.
Published: August 2018

Infertility is a disease that affects up to 15.5% of reproductive-aged couples. Until the birth of the first neonate born from in vitro fertilization (IVF) in 1978, many infertile couples did not have an opportunity to conceive a biological child. Over the past 40 years, access to and effectiveness of IVF have increased; currently 1.7% of births in the United States result from IVF. As with any medical intervention, potential risk exists. In the case of IVF, both maternal risks (ovarian stimulation, oocyte retrieval, and subsequent pregnancy) and fetal risks that vary based on maternal age and fetal number must be considered. Importantly, risk quantification varies by comparison group, which is typically either spontaneous conception in a fertile couple or assisted non-IVF conception in an infertile couple. It must also be considered compared with the alternative of not undergoing IVF, which may mean not having a biological child. Although increased compared with spontaneous conception, absolute maternal–fetal-assisted reproductive technology risks are low and can be minimized by optimizing ovarian stimulation and transferring a single embryo. In this article, we aim to summarize maternal and fetal risk associated with use of assisted reproductive technology. The review focuses on ovarian stimulation and procedural risks as well as adverse perinatal outcomes among resultant singleton and twin pregnancies in young women and women of advanced maternal age.
Implementation of a Quality Improvement Initiative to Decrease Opioid Prescribing After Cesarean Delivery
Authors: Prabhu Malavika , Dubois Heloise , James Kaitlyn , Leffert Lisa R. , Riley Laura E. , Bateman Brian T. , Henderson Marie
Published: August 2018

OBJECTIVE:

To assess whether a multiphase, departmental quality improvement effort decreases opioid prescribing and increases multimodal analgesic use after cesarean delivery.

METHODS:

This is a prospective quality improvement study. In phase 1 of the protocol, discharge providers implemented counseling regarding expectations for pain, typical need for opioids, and importance of multimodal nonopioid analgesic use and used shared decision-making to determine the number of opioids prescribed. Patients could select up to a maximum of 30 tablets of 5 mg oxycodone (or equivalent opioid), lower than the previous routine discharge prescription of 40 opioid tablets. The primary outcome was the mean (SD) number of opioid tablets prescribed on discharge with secondary outcomes including opioid refill rate within 30 days of discharge and rates of nonopioid analgesic prescriptions on discharge. In phase 2, using these results, we adjusted the protocol's maximum opioid prescription to 25 opioid tablets, but no other aspects of the protocol were changed. All data were analyzed with t test and χ2 analyses.

RESULTS:

Data from 624 women who underwent cesarean deliveries were analyzed. Opioids, most commonly oxycodone, were prescribed after 95% of all cesarean deliveries. The mean (SD) number of opioid tablets prescribed decreased from 33.2 (9.3) to 26.5 (6.7; P<.01) with the implementation of phase 1 having no effect on the opioid refill rate, 8.9% vs 8.1% (P=.79). These results allowed adjustment of the maximum recommended prescription to 25 opioid tablets, introducing phase 2 of the study, during which the mean (SD) number of opioid tablets prescribed further decreased from 24.9 (7.5) to 21.5 (6.3; P<.01) with no effect on the opioid refill rate, 6.3% vs 5.1% (P=.72). Overall, this represents a 35% decrease in opioid prescribing (P<.01). Rates of ibuprofen prescribing were 98% or higher throughout the study, but rates of acetaminophen prescribing increased from 32.6% before phase 1 to 92.0% after phase 2 (P<.001).

CONCLUSION:

Implementation of a multiphase quality improvement protocol to decrease opioid prescribing, combined with iterative review of discharge data, resulted in a significant decrease in the number of opioid tablets prescribed after cesarean delivery.
Paracervical Block for Intrauterine Device Placement Among Nulliparous Women
Authors: Mody Sheila K. , Farala John Paul , Jimenez Berenice , Nishikawa Moena , Ngo Lynn L.
Published: August 2018

OBJECTIVE:

To investigate whether a 20-mL buffered 1% lidocaine paracervical block decreases pain during intrauterine device (IUD) placement.

METHODS:

In a randomized, single-blind, placebo-controlled trial, women were assigned to receive either a 20-mL buffered 1% lidocaine paracervical block or no block before IUD placement. The primary outcome was pain with IUD placement measured on a 100-mm visual analog scale. Our sample size had 80% power (α=0.05) to detect a 20-mm difference in visual analog scale scores with a SD of 28 mm. Secondary outcomes included pain with speculum placement, paracervical block administration, tenaculum placement, 5 minutes postprocedure, and overall pain perception.

RESULTS:

From October 7, 2014, through October 26, 2017, 64 women were enrolled and analyzed (33 in the paracervical block arm, 31 in the no-block arm). There were no differences in baseline demographics between the groups. Women who received the paracervical block reported less pain with IUD placement compared with women who received no block (median visual analog scale score of 33 mm vs 54 mm, P=.002). Pain was significantly less in the intervention group for uterine sounding (30 mm vs 47 mm, P=.005), 5 minutes after placement (12 mm vs 27 mm, P=.005), and overall pain perception (30 mm vs 51 mm, P=.015). Participants who received the paracervical block experienced more pain with block administration compared with placebo (30 mm vs 8 mm, P=.003). There was no perceived pain difference for speculum insertion (10 mm vs 6 mm, P=.447) or tenaculum placement (15 mm vs 10 mm, P=.268).

CONCLUSION:

A 20-mL buffered 1% lidocaine paracervical block decreases pain with IUD placement (primary outcome), uterine sounding (secondary outcome), and 5 minutes after placement (secondary outcome). Although paracervical block administration can be painful, perception of pain for overall IUD placement procedure is lower compared with no block.

CLINICAL TRIAL REGISTRATION:

ClinicalTrials.gov, NCT02219308.
Association of a Health Care Provider Review Meeting With Cesarean Delivery Rates
Authors: Skeith Ashley E. , Valent Amy M. , Marshall Nicole E. , Pereira Leonardo M. , Caughey Aaron B.
Published: August 2018

OBJECTIVE:

To examine the association of a quality improvement effort that was mediated through weekly review of all criteria for cesarean delivery on cesarean delivery prevalence and indications.

METHODS:

We conducted a retrospective cohort study using a natural experiment model that compared two timeframes, from 2009 to 2013, at a single institution. We introduced a weekly retrospective review conference to discuss all cesarean deliveries in 2010 that continued over time. The conferences were attended by obstetric care providers, anesthesiology, and labor and delivery nurses. Date of delivery was dichotomized by those delivering before July 1, 2010, and those delivering after. We included women with term singleton vertex gestations in our study population and then examined the rates of cesarean delivery by date of delivery. We then examined indications for the cesarean deliveries during the study period based on surgeon documentation. χ2 tests were used for statistical comparisons and a P value of <.05 was used to indicate statistical significance.

RESULTS:

There were 5,541 term singleton cephalic births during the study period. The rate of cesarean delivery declined significantly after our intervention in all women (22.2% vs 27.4%, P<.001) and nulliparous women (23.3% vs 30.9%, P<.001). The adjusted odds ratio of cesarean delivery in all women as related to time cohort is 0.68 (95% CI 0.58–0.79) and 0.56 (95% CI 0.44–0.70) in nulliparous women. We examined indications for the 1,315 cesarean deliveries during the study period by date of delivery. The indications of active-phase arrest, second-stage arrest, failed induction, repeat cesarean delivery, and maternal request decreased significantly between delivery cohorts in all women (P<.001) and in nulliparous women specifically (P<.001). Between delivery cohorts, we found that the prevalence of labored indications for cesarean delivery decreased more than nonlabored indications.

CONCLUSION:

Implementation of a weekly review conference was associated with a reduction in both overall cesarean delivery prevalence and labored indications at our institution.
Timing of Delivery in Women With Chronic Hypertension
Authors: Ram Maya , Berger Howard , Geary Michael , McDonald Sarah D. , Murray-Davis Beth , Riddell Catherine , Hasan Haroon , Barrett Jon , Melamed Nir ,   for the Diabetes, Obesity and Hypertension in Pregnancy Research Network (DOH-NET) and the Southern Ontario Obstetrical Network (SOON) Investigators
Published: August 2018

OBJECTIVE:

To assess whether routine induction of labor at 38 or 39 weeks in women with chronic hypertension is associated with the risk of superimposed preeclampsia or cesarean delivery.

METHODS:

We conducted a retrospective population-based study of women with chronic hypertension who had a singleton hospital birth at 38 0/7 weeks of gestation of gestation in Ontario, Canada, between 2012 and 2016. Women who underwent induction of labor at 38 0/7 to 38 6/7 weeks of gestation for chronic hypertension (n=281) were compared with those who were managed expectantly during that week and remained undelivered at 39 0/7 weeks of gestation (n=1,606). Separately, women who underwent induction of labor at 39 0/7 to 39 6/7 weeks of gestation for chronic hypertension (n=259) were compared with women who remained undelivered at 40 0/7 weeks of gestation (n=801).

RESULTS:

Of 534,529 women gave birth during the study period, 6,054 (1.1%) had chronic hypertension and 2,420 met the inclusion criteria. Women managed expectantly at 38 or 39 weeks of gestation were at risk of new-onset superimposed preeclampsia (19.2% [308/1,606] and 19.0% [152/801], respectively) and eclampsia (0.6% [10/1,606] and 0.7% [6/801], respectively), and more than half underwent induction of labor later in gestation (56.8% and 57.8%, respectively). The risk of cesarean delivery in the induction groups was lower (38 weeks of gestation) or similar (39 weeks of gestation) to that observed in women managed expectantly at the corresponding weeks (38 weeks of gestation: 17.1% vs 24.0%, adjusted relative risk 0.74 [95% CI 0.57–0.95]; 39 weeks of gestation: 20.1% vs 26.0%, adjusted relative risk 0.90 [95% CI 0.69–1.17]).

CONCLUSION:

Our findings suggest that in women with isolated chronic hypertension, induction of labor at 38 or 39 weeks of gestation may prevent severe hypertensive complications without increasing the risk of cesarean delivery.
Disparities in Human Papillomavirus Vaccine Completion Rates Among Females in an Integrated Health Care System
Authors: Freeman Alexandra (Jana) H. , Gamboa Cristina , Darbinian Jeanne A. , Littell Ramey D. , Torrente Sandra
Published: August 2018

OBJECTIVE:

To estimate the rate of human papillomavirus (HPV) vaccine completion by race and ethnicity.

METHODS:

In this retrospective cohort study, we analyzed females aged 11–26 years who initiated HPV vaccination from 2008 through 2012 in a community-based health care system in California. Vaccine completion was defined as having received at least three injections. Demographic data including age, race, ethnicity, and language preferences were obtained. Among Hispanic patients, acculturation was categorized as low or high using written and spoken Spanish vs English language as a proxy. Age groups were defined as younger adolescents (11–14 years), teens (15–17 years), and young adults (18–26 years). Bivariate analyses using χ2 tests and age-adjusted logistic regression were performed.

RESULTS:

Among 102,052 females who initiated HPV vaccination, a total of 41,847 (41%) completed the series. Younger adolescents had the highest completion rates (43.4%, P<.001) vs teens and young adults (37.4% and 38.0%, respectively). By race and ethnicity, Asian patients had the highest completion rates (49.5%, 95% CI 48.8–50.2), and the lowest rates were seen among black and Hispanic patients (28.7% [95% CI 27.8–29.6] and 38.9% [95% CI 38.3–39.5], respectively). Among Hispanic patients, the adjusted odds for vaccine completion was 1.2-fold higher for the low acculturated vs the highly acculturated group (adjusted odds ratio 1.23 [95% CI 1.16–1.31]).

CONCLUSION:

More than half of the females who initiated HPV vaccination did not complete the series, and black and Hispanic patients were least likely to have completed the series. Among Hispanic patients, the highest acculturated group had the lowest completion rate. These disparities emphasize the need for cancer prevention across all racial and ethnic groups.
Prevalence of Maternal Hepatitis C Virus Infection in Ohio
Authors: Rossi Robert M. , Warshak Carri R.
Published: August 2018

OBJECTIVE:

To quantify the rising prevalence of maternal hepatitis C virus (HCV) infection in Ohio during the peak of the opioid epidemic and to identify maternal characteristics and obstetric outcomes associated with maternal HCV infection.

METHODS:

We conducted a population-based retrospective cohort study of all live births in Ohio (2006–2015). Frequency of maternal HCV infection as reported on birth certificates was compared across each year of the study period. Maternal, obstetric, and neonatal characteristics were compared between women with HCV infection in pregnancy with those without HCV infection. Multivariate logistic regression estimated the relative association between HCV infection and various maternal characteristics and obstetric outcomes.

RESULTS:

During the 10-year study period, there were 7,069 reported cases of maternal HCV infection at the time of delivery among 1,463,506 (0.5%) live births in Ohio. The rate of maternal HCV infection increased 631% between 2006 and 2015, from 1.6 to 11.7 cases per 1,000 live births (relative risk [RR] 7.6, CI 6.6–8.7, P<.001). After adjusting for various confounders, demographic characteristics associated with HCV infection included cigarette smoking (adjusted RR 8.6, CI 8.0–9.1), Medicaid insurance (adjusted RR 3.6, CI 3.3–3.8), and white, non-Hispanic race (adjusted RR 3.2, 95% CI 2.9–3.5). Coinfection during pregnancy with hepatitis B, gonorrhea, chlamydia, syphilis, and herpes simplex virus infection was also associated with maternal HCV infection. Obstetric and neonatal outcomes associated with maternal HCV infection included cesarean delivery, fetal intolerance of labor, preterm birth, maternal intensive care unit admission, blood transfusion, small for gestational age (less than the 10th percentile), neonatal intensive care unit admission, need for assisted neonatal ventilation, and infant death.

CONCLUSION:

Maternal HCV infection has increased more than sevenfold over the past decade in Ohio. Our findings highlight a dramatic rise in maternal HCV infection that parallels the opioid epidemic within Ohio and in neighboring Appalachian states.
Safety and Complications Associated With MRI-Conditional External Fixators in Patients With Tibial Plateau Fractures: A Case Series
Authors: Gillig Jonathan D. , Goode Russell D. , Campfield Brian , Crim Julia R. , Crist Brett D.
Published: August 2018

Objectives:

To address the safety of obtaining magnetic resonance imaging (MRI) in patients with temporary knee-spanning external fixators placed for tibial plateau fractures.

Design:

Institutional Review Board–approved retrospective review.

Setting:

Level 1 trauma center.

Patients/Participants:

Records were reviewed on patients with knee-spanning external fixators applied during staged management of tibial plateau fractures from 2009 to 2015 and who also had an MRI performed.

Main Outcome Measurements:

Complications associated with the MRI; secondary outcomes were pain scores, narcotic requirements, and fracture healing.

Results:

A total of 56 patients with 57 fractures were included, and 55 scans (96.5%) were completed without complication. Two scans (3.5%) were stopped prematurely for patient-reported pain and subjective warmth of the external fixator. For all 57 studies, pain scores and narcotic usage were unchanged, and all fractures healed without complication.

Conclusions:

Knee-spanning external fixator placement does not preclude MRI for patients with tibial plateau fractures. MRIs can be safely performed on patients with external fixators if patients are educated before imaging. Even in the small percentage of patients who experienced discomfort, there were no long-term complications.

Level of Evidence:

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Intramedullary Fixation Techniques for the Anterior Pelvic Ring
Authors: Eastman Jonathan G. , Chip Routt Milton L.
Published: August 2018

The superior ramus is an irregularly shaped, undulating, and curvilinear osseous structure that can provide an osseous conduit for intramedullary screws. A wide spectrum of variability between the curve and obliquity of the superior ramus osseous fixation pathway (OFP) exists in both the anteroposterior and the coronal planes. A detailed understanding of the osseous topography and how it correlates with fluoroscopic imaging is mandatory. Obtaining the correct intraoperative inlet and combined obturator oblique–outlet fluoroscopic views specific to each patient's anatomy is necessary for safe implant insertion. Intramedullary screws can be inserted in either an antegrade or a retrograde direction depending on a number of variables, including fracture location, the proximity of patient's external genitalia to the skin insertion side, and the possible impact of thigh girth on the surgeons hand position. Multiple screw insertion techniques are possible, but a simple and reproducible technique is described. The size and number of screws that can be inserted is variable, differs between surgeons, but is ultimately dependent on the cortical limits of the superior ramus OFP. Standard screw insertion techniques are successful in most patients. If the osseous corridor or external anatomy impedes standard insertional techniques, several modifications exist that can allow successful screw insertion. A thorough understanding of each patient's anatomy, injury, and precise surgical technique with the appropriate fluoroscopic views are required to safely place intraosseous intramedullary implants into the superior ramus OFP.
Long Segment Blocking Screws Increase the Stability of Retrograde Nail Fixation in Geriatric Supracondylar Femur Fractures: Eliminating the “Bell-Clapper Effect”
Authors: Auston Darryl , Donohue David , Stoops Kyle , Cox Jacob , Diaz Miguel , Santoni Brandon , Mir Hassan
Published: August 2018

Objectives:

To determine the change in stiffness and horizontal translations of a geriatric supracondylar femur fracture model with the addition of distal segment blocking screws versus proximal (long) segment blocking screws to the standard retrograde intramedullary nail construct.

Methods:

Unstable supracondylar femur fractures (OTA/AO 33-A3) were created; all specimens were instrumented with a retrograde intramedullary nail. Specimens were divided into 2 groups (6 matched pairs per group). Group 1 compared the standard construct (1 proximal screw and 3 distal screws) to a distally augmented construct, with blocking screws placed in the distal metaphyseal segment. Group 2 compared the distally augmented construct to one in which blocking screws were placed just proximal to the fracture (long segment blocking screws). Specimens were then axially loaded and cycled to failure or run-out.

Results:

There was no significant difference in baseline stiffness, survival through cyclic loading, stiffness after cyclic loading, or cycles to failure between femurs treated with distal blocking screws and femurs treated without blocking screws (group 1). Femurs with blocking screws in the long proximal segment had significantly greater baseline stiffness, stiffness after cyclic loading, and less horizontal translation at the fracture site (group 2). There was no difference in survival through cyclic loading or cycles to failure.

Conclusion:

Long segment blocking screws are biomechanically superior to blocking screws in the distal segment or no blocking screws initially and after cyclic loading in an unstable geriatric supracondylar femur fracture model treated with intramedullary nail.

Clinical Relevance:

Surgeons may use blocking screws to aid in fracture alignment during retrograde nail fixation. In addition, the placement of long segment blocking screws can help resist failure of fixation in geriatric patients by eliminating the “Bell-clapper effect.”
Posterior Spinal Fusion in a Scoliotic Patient With Congenital Heart Block Treated With Pacemaker
Authors: Wong Tat Seng , Abu Bakar Jaseemuddeen , Chee Kok Han , Hasan Mohd Shahnaz , Chung Weng Hong , Chiu Chee Kidd , Chan Chris Yin Wei , Kwan Mun Keong
Published: August 2018

Study Design.

Case report.

Objective.

To describe the technical difficulties on performing posterior spinal fusion (PSF) on a pacemaker-dependent patient with complete congenital heart block and right thoracic scoliosis.

Summary of Background Data.

Congenital complete heart block requires pacemaker implantation at birth through thoracotomy, which can result in scoliosis. Corrective surgery in this patient was challenging. Height gain after corrective surgery may potentially cause lead dislodgement. The usage of monopolar electrocautery may interfere with the function of the implanted cardiac device.

Methods.

A 17-year-old boy was referred to our institution for the treatment of right thoracic scoliosis of 70°. He had underlying complete congenital heart block secondary to maternal systemic lupus erythematosus. Pacemaker was implanted through thoracotomy since birth and later changed for four times. PSF was performed by two attending surgeons with a temporary pacing inserted before the surgery. The monopolar electrocautery device was used throughout the surgery.

Results.

The PSF was successfully performed without any technical issues and complications. Postoperatively, his permanent pacemaker was functioning normally. Three days later, he was recovering well and was discharged home from hospital.

Conclusion.

This case indicates that PSF can be performed successfully with thoughtful anticipation of technical difficulties on a pacemaker-dependent patient with underlying congenital heart block.

Level of Evidence: 5
Sources of Patients’ Expectations of Lumbar Surgery
Authors: Mancuso Carol A. , Duculan Roland , Cammisa Frank P. , Sama Andrew A. , Hughes Alexander P. , Lebl Darren R. , Girardi Federico P.
Published: August 2018

Study Design.

A cross-sectional, mixed methods analysis of sources of expectations of lumbar surgery.

Objective.

The aim of this study was to ascertain sources of expectations and compare them to clinical characteristics.

Summary of Background Data.

Understanding where patients obtain expectations of lumbar surgery is necessary in order to develop interventions to foster appropriate expectations.

Methods.

This was a qualitative-quantitative study of 428 patients interviewed preoperatively with a 20-item validated survey, which asks patients how much improvement they expect per item. Patients then were asked open-ended questions about how they came to have these expectations and, using qualitative analysis, responses were grouped into themes representing different sources of expectations. The likelihood of citing various sources was then assessed with odds ratios (ORs) based on demographic and clinical characteristics.

Results.

Patients’ mean age was 55 years, 80% had degenerative diagnoses and 24% had prior lumbar surgery. Patients volunteered multiple sources; most prevalent were current surgeon (83%), internet resources (55%), social network contacts (26%), other physicians (22%); and previous experience (65%) for the subgroup who had prior lumbar surgery. Patients were more likely to cite their surgeon if they had less disability [OR 2.8, confidence interval (CI) 1.3–5.8, P = 0.007], were treated with conservative care, such as physical therapy (OR 2.7, CI 1.6–4.7, P = 0.0003), and had symptoms for ≤12 months (OR 1.8, CI 1.1–3.0, P = 0.03). Patients who cited the internet were employed (OR 2.2; CI 1.5–3.3; P < 0.0001), were treated with physical therapy (OR 1.9; CI 1.2–3.1; P = 0.006), had a negative screen for depression (OR 1.8; CI 1.2–2.8; P = 0.004), and were younger (OR 1.6; CI 1.1–2.4; P = .02). Patients were less likely to expect complete improvement for most items of the survey if they had prior lumbar surgery (P = 0.002) or other orthopedic surgery (P = 0.02).

Conclusion.

Patients derive their expectations of lumbar surgery from multiple sources. Some sources are modifiable through enhanced communication with surgeons and potentially through novel modes of education, such as web-based resources that are specifically designed to address expectations.

Level of Evidence: 2