Predicting postoperative day 1 hematocrit levels after uncomplicated hysterectomy

ObjectiveTo develop a model for predicting postoperative hematocrit levels after uncomplicated hysterectomy.MethodsIn a retrospective study, data were analyzed from the Michigan Surgery Quality Collaborative for non‐emergent hysterectomies performed for benign indications among women aged at least 18 years between January 1, 2012, and April 4, 2014. Linear mixed models were used for univariate and multivariate analyses.ResultsThe model was developed with data from 4747 hysterectomies and validated on 1184 cases. In the mixed multivariate analysis, higher postoperative day 1 (POD1) hematocrit levels were associated with higher weight (B = 0.03222, P < 0.001), higher preoperative hematocrit (B = 0.6587, P < 0.001), and non‐vaginal hysterectomy (B = 0.2815, P = 0.0055). Lower POD1 hematocrit was associated with higher preoperative platelet count (B = − 0.00457, P < 0.001), greater estimated blood loss (B = − 0.00652, P < 0.001), and larger intraoperative crystalloid volume (B = − 0.3303, P < 0.001). The final model predicted POD1 hematocrit within 4% points of the actual value for 91.7% of cases in the validation set.ConclusionUse of the model after uncomplicated hysterectomy might help to support the practice of selectively conducting postoperative hematocrit tests after hysterectomy in a clinically thoughtful and cost‐effective manner.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135182/1/ijgo19.pd

Rates of colpopexy and colporrhaphy at the time of hysterectomy for prolapse Q1

BACKGROUND: It has Q8 been shown that addressing apical support at the time of hysterectomy for pelvic organ prolapse (POP) reduces recurrence and reoperation rates. In fact, national guidelines consider hysterectomy alone to be inadequate treatment for POP. Despite this, anterior and posterior colporrhaphy are frequently performed without a colpopexy procedure and hysterectomy alone is often utilized for treatment of prolapse. OBJECTIVE: The objectives of this study were to: (1) determine rates of concomitant procedures for POP in hysterectomies performed with POP as an indication, (2) identify factors associated with performance of a colpopexy at the time of hysterectomy for POP, and (3) identify the influence of surgical complexity on perioperative complication rates. STUDY DESIGN: This is a retrospective cohort study of hysterectomies performed for POP from Jan. 1, 2013, through May 7, 2014, in a statewide surgical quality database. Patients were stratified based on procedures performed: hysterectomy alone, hysterectomy with colporrhaphy and without apical suspension, and hysterectomy with colpopexy with or without colporrhaphy. Demographics, medical history and intraoperative care, and perioperative care were compared between the groups. Multivariable logistic regression models were created to identify factors independently associated with use of colpopexy and factors associated with increased rates of postoperative complications. RESULTS: POP was an indication in 1557 hysterectomies. Most hysterectomies were vaginal (59.6%), followed by laparoscopic or robotic (34.1%), and abdominal (6.2%). Hysterectomy alone was performed in 43.1% (95% confidence interval [CI], 40.6e45.6) of cases, 32.8% (95% CI, 30.4e35.1) had a colporrhaphy without colpopexy, and 24.1% (95% CI, 22e26.3) had a colpopexy with or without colporrhaphy. Use of colpopexy was independently associated with patient age &gt;40 years, POP as the only indication for surgery (odd ratio [OR], 1.6; 95% CI, 1.185e2.230), laparoscopic surgery (OR, 3.2; 95% CI, 2.860e5.153), and a surgeon specializing in urogynecology (OR, 8.2; 95% CI, 5.156e12.923). The overall perioperative complication rate was 6.6%, with the majority being considered minor. Complications were more likely when the procedure was performed with an abdominal approach (OR, 2.3; 95% CI, 1.088e4.686), with the use of a colpopexy procedure (OR, 3.1; 95% CI, 1.840e5.194), and by a surgeon specializing in urogynecology (OR, 2.2; 95% CI, 1.144e4.315). CONCLUSION: Colpopexy and colporrhaphy may be underutilized and are potential targets for quality improvement. Performance of additional procedures at the time of hysterectomy increased the rate of perioperative complications. Long-term consequences of these surgical practices deserve additional study

Writhe in the Stretch-Twist-Fold Dynamo

This is an Author's Original Manuscript of an article whose final and definitive form, the Version of Record, has been published in Geophysical and Astrophysical Fluid Dynamics (2008) Copyright © 2008 Taylor & Francis, available online at: http://www.tandfonline.com/10.1080/03091920802531791This article looks at the influence of writhe in the stretch-twist-fold dynamo. We consider a thin flux tube distorted by simple stretch, twist, and fold motions and calculate the helicity and energy spectra. The writhe number assists in the calculations, as it tells us how much the internal twist changes as the tube is distorted. In addition it provides a valuable diagnostic for the degree of distortion. Non mirror-symmetric dynamos typically generate magnetic helicity of one sign on large-scales and the opposite sign on small scales. The calculations presented here confirm the hypothesis that the large-scale helicity corresponds to writhe and the small scale corresponds to twist. In addition, the writhe helicity spectrum exhibits an interesting oscillatory behavior. The technique of calculating Fourier spectra for the writhe helicity may be useful in other areas of research, for example, the study of highly coiled molecules

Role of intergrowths in the properties of the naturally layered manganites.

The structural and magnetic properties of the two-layered Ruddlesden-Popper phase SrO(La{sub 1{minus}x}Sr{sub x}MnO{sub 3}){sub 2} with x = 0.3 and x = 0.4 are investigated. These naturally layered manganites exhibit a colossal magnetoresistance, a magnetic anisotropy which is strongly composition-dependent, almost no remanence, and a non-vanishing magnetization in an extended temperature range above the Curie temperature (T{sub c}). The magnetization in this temperature range is not intrinsic to the crystal, but is attributed to intergrowths. These two-dimensional lattice imperfections consist of additional or missing SrO layers and have been observed in transmission electron micrographs. The magnetic properties of the intergrowths differ from the bulk crystal which results in unusual magnetic behavior

Magnetization relaxation in (Ga,Mn)As ferromagnetic semiconductors

We describe a theory of Mn local-moment magnetization relaxation due to p-d kinetic-exchange coupling with the itinerant-spin subsystem in the ferromagnetic semiconductor (Ga,Mn)As alloy. The theoretical Gilbert damping coefficient implied by this mechanism is calculated as a function of Mn moment density, hole concentration, and quasiparticle lifetime. Comparison with experimental ferromagnetic resonance data suggests that in annealed strongly metallic samples, p-d coupling contributes significantly to the damping rate of the magnetization precession at low temperatures. By combining the theoretical Gilbert coefficient with the values of the magnetic anisotropy energy, we estimate that the typical critical current for spin-transfer magnetization switching in all-semiconductor trilayer devices can be as low as $\sim 10^{5} {\rm A cm}^{-2}$.Comment: 4 pages, 2 figures, submitted to Rapid Communication

Convergence of AMR and SPH simulations - I. Hydrodynamical resolution and convergence tests

We compare the results for a set of hydrodynamical tests performed with the adaptive mesh refinement finite volume code, MG, and the smoothed particle hydrodynamics (SPH) code, SEREN. The test suite includes shock tube tests, with and without cooling, the non-linear thin-shell instability and the Kelvin–Helmholtz instability. The main conclusions are the following. (i) The two methods converge in the limit of high resolution and accuracy in most cases. All tests show good agreement when numerical effects (e.g. discontinuities in SPH) are properly treated. (ii) Both methods can capture adiabatic shocks and well-resolved cooling shocks perfectly well with standard prescriptions. However, they both have problems when dealing with under-resolved cooling shocks, or strictly isothermal shocks, at high Mach numbers. The finite volume code only works well at first order and even then requires some additional artificial viscosity. SPH requires either a larger value of the artificial viscosity parameter, αAV, or a modified form of the standard artificial viscosity term using the harmonic mean of the density, rather than the arithmetic mean. (iii) Some SPH simulations require larger kernels to increase neighbour number and reduce particle noise in order to achieve agreement with finite volume simulations (e.g. the Kelvin–Helmholtz instability). However, this is partly due to the need to reduce noise that can corrupt the growth of small-scale perturbations (e.g. the Kelvin–Helmholtz instability). In contrast, instabilities seeded from large-scale perturbations (e.g. the non-linear thin shell instability) do not require more neighbours and hence work well with standard SPH formulations and converge with the finite volume simulations. (iv) For purely hydrodynamical problems, SPH simulations take an order of magnitude longer to run than finite volume simulations when running at equivalent resolutions, i.e. when they both resolve the underlying physics to the same degree. This requires about two to three times as many particles as the number of cells

Integrative Genomics Viewer

Author Manuscript 2012 May 07.To the Editor: Rapid improvements in sequencing and array-based platforms are resulting in a flood of diverse genome-wide data, including data from exome and whole-genome sequencing, epigenetic surveys, expression profiling of coding and noncoding RNAs, single nucleotide polymorphism (SNP) and copy number profiling, and functional assays. Analysis of these large, diverse data sets holds the promise of a more comprehensive understanding of the genome and its relation to human disease. Experienced and knowledgeable human review is an essential component of this process, complementing computational approaches. This calls for efficient and intuitive visualization tools able to scale to very large data sets and to flexibly integrate multiple data types, including clinical data. However, the sheer volume and scope of data pose a significant challenge to the development of such tools.National Institute of General Medical Sciences (U.S.) (R01GM074024)National Cancer Institute (U.S.) (R21CA135827)National Human Genome Research Institute (U.S.) (U54HG003067

The formation of professional identity in medical students: considerations for educators

&lt;b&gt;Context&lt;/b&gt; Medical education is about more than acquiring an appropriate level of knowledge and developing relevant skills. To practice medicine students need to develop a professional identity – ways of being and relating in professional contexts.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Objectives&lt;/b&gt; This article conceptualises the processes underlying the formation and maintenance of medical students’ professional identity drawing on concepts from social psychology.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Implications&lt;/b&gt; A multi-dimensional model of identity and identity formation, along with the concepts of identity capital and multiple identities, are presented. The implications for educators are discussed.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Conclusions&lt;/b&gt; Identity formation is mainly social and relational in nature. Educators, and the wider medical society, need to utilise and maximise the opportunities that exist in the various relational settings students experience. Education in its broadest sense is about the transformation of the self into new ways of thinking and relating. Helping students form, and successfully integrate their professional selves into their multiple identities, is a fundamental of medical education