Pulmonary arterial pulsus alternans secondary to primary pulmonary hypertension.

Pulsus alternans of the pulmonary artery without systemic pulsus alternans is uncommon and is associated with multiple diseases. Two cases of pulmonary hypertension with pulmonary arterial pulsus alternans and right-sided heart failure are described. Primary pulmonary hypertension was demonstrated at autopsy in both cases. These two case reports constitute another previously unreported cause for pulsus alternans in the pulmonary circuit.     

Double-scope per oral endoscopic myotomy (POEM): a prospective randomized controlled trial

Background

Since its introduction in 2010, per oral endoscopic myotomy (POEM) has offered an alternative to laparoscopic Heller myotomy for the treatment of achalasia. A gastric myotomy length of 3 cm has been recommended; however, it can be difficult to ensure that adequate submucosal dissection has been performed during the procedure. Commonly accepted endoscopic markers of the gastric side can be inaccurate, particularly in patients with prior endoscopic treatments, such as balloon dilation or Botox injection of the lower esophageal sphincter. We hypothesized that the use of a second endoscope would result in a more complete gastric myotomy.

Methods

One hundred consecutive achalasia patients were randomized into single- and double-scope POEM groups. In the treatment group, a second endoscope was used to obtain a retroflexed view of the gastric cardia, while the dissecting scope transilluminated from the end of the submucosal tunnel. Prospectively collected data were analyzed, including myotomy lengths, procedure times, adverse events, and clinical outcomes.

Results

POEM was completed with high rates of technical (98–100 %) and clinical success (93–97 %) in both groups, with a low rate of serious adverse events (2 %). The second endoscope resulted in a 17 min increase in procedure time (94 vs. 77 min), myotomy extension in 34 % of cases, and an increase in the average gastric myotomy length from 2.6 to 3.2 cm (p = 0.01).

Conclusion

A second endoscope is useful for ensuring a complete gastric myotomy during POEM. With minimal increase in procedure time and no increase in morbidity, it may be particularly useful in cases of sigmoid esophagus or otherwise altered anatomy that makes identification of the gastroesophageal junction difficult.

     

Cost-Effectiveness in Global Surgery: Pearls,Pitfalls, and a Checklist

Introduction

Cost-effectiveness analysis can be a powerful policy-making tool. In the two decades since the first cost-effectiveness analyses in global surgery, the methodology has established the cost-effectiveness of many types of surgery in low- and middle-income countries (LMICs). However, with the crescendo of cost-effectiveness analyses in global surgery has come vast disparities in methodology, with only 15% of studies adhering to published guidelines. This has led to results that have varied up to 150-fold.

Methods

The theoretical basis, common pitfalls, and guidelines-based recommendations for cost-effectiveness analyses are reviewed, and a checklist to be used for cost-effectiveness analyses in global surgery is created.

Results

Common pitfalls in global surgery cost-effectiveness analyses fall into five categories: the analytic perspective, cost measurement, effectiveness measurement, probability estimation, valuation of the counterfactual, and heterogeneity and uncertainty. These are reviewed in turn, and a checklist to avoid these pitfalls is developed.

Conclusion

Cost-effectiveness analyses, when done rigorously, can be very useful for the development of efficient surgical systems in LMICs. This review highlights the common pitfalls in these analyses and methods to avoid these pitfalls.

     

Three-dimensional volume rendering of spiral CT data: theory and method.

Three-dimensional (3D) medical images of computed tomographic (CT) data sets can be generated with a variety of computer algorithms. The three most commonly used techniques are shaded surface display, maximum intensity projection, and, more recently, 3D volume rendering. Implementation of 3D volume rendering involves volume data management, which relates to operations including acquisition, resampling, and editing of the data set; rendering parameters including window width and level, opacity, brightness, and percentage classification; and image display, which comprises techniques such as "fly-through" and "fly-around," multiple-view display, obscured structure and shading depth cues, and kinetic and stereo depth cues. An understanding of both the theory and method of 3D volume rendering is essential for accurate evaluation of the resulting images. Three-dimensional volume rendering is useful in a wide variety of applications but is just now being incorporated into commercially available software packages for medical imaging. Although further research is needed to determine the efficacy of 3D volume rendering in clinical applications, with wider availability and improved cost-to-performance ratios in computing, 3D volume rendering is likely to enjoy widespread acceptance in the medical community.     

Cost-effectiveness of Surgery in Low- and Middle-income Countries: A Systematic Review

Background

There is increasing interest in provision of essential surgical care as part of public health policy in low- and middle-income countries (LMIC). Relatively simple interventions have been shown to prevent death and disability. We reviewed the published literature to examine the cost-effectiveness of simple surgical interventions which could be made available at any district hospital, and compared these to standard public health interventions.

Methods

PubMed and EMBASE were searched using single and combinations of the search terms “disability adjusted life year” (DALY), “quality adjusted life year,” “cost-effectiveness,” and “surgery.” Articles were included if they detailed the cost-effectiveness of a surgical intervention of relevance to a LMIC, which could be made available at any district hospital. Suitable articles with both cost and effectiveness data were identified and, where possible, data were extrapolated to enable comparison across studies.

Results

Twenty-seven articles met our inclusion criteria, representing 64 LMIC over 16 years of study. Interventions that were found to be cost-effective included cataract surgery (cost/DALY averted range US$5.06–$106.00), elective inguinal hernia repair (cost/DALY averted range US$12.88–$78.18), male circumcision (cost/DALY averted range US$7.38–$319.29), emergency cesarean section (cost/DALY averted range US$18–$3,462.00), and cleft lip and palate repair (cost/DALY averted range US$15.44–$96.04). A small district hospital with basic surgical services was also found to be highly cost-effective (cost/DALY averted 1 US$0.93), as were larger hospitals offering emergency and trauma surgery (cost/DALY averted US$32.78–$223.00). This compares favorably with other standard public health interventions, such as oral rehydration therapy (US$1,062.00), vitamin A supplementation (US$6.00–$12.00), breast feeding promotion (US$930.00), and highly active anti-retroviral therapy for HIV (US$922.00).

Conclusions

Simple surgical interventions that are life-saving and disability-preventing should be considered as part of public health policy in LMIC. We recommend an investment in surgical care and its integration with other public health measures at the district hospital level, rather than investment in single disease strategies.     

Sex Disparities in Risk of Mortality Among Children With ESRD

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Neural functional and structural correlates of childhood maltreatment in women with intimate-partner violence-related posttraumatic stress disorder

Childhood maltreatment (CM) is a strong risk factor for development of posttraumatic stress disorder (PTSD) upon adult exposure to extreme adverse events. However, the neural underpinnings of this relationship are not well understood. Here, we test the hypothesis that severity of CM history is positively correlated with emotion-processing limbic and prefrontal brain activation/connectivity and negatively correlated with prefrontal gray matter volumes in women with PTSD due to intimate-partner violence (IPV-PTSD). Thirty-three women with IPV-PTSD underwent structural and functional magnetic resonance imaging while completing a facial emotion processing task. Multivariate regressions examined the relationship of CM to patterns of activation, connectivity, and gray matter volumes. CM severity was: (a) positively correlated with ventral ACC activation while processing angry faces; (b) negatively correlated with dorsal ACC and insula activation while processing fear and angry faces, arising from positive correlations with the shape-matching baseline; (c) positively correlated with limbic–prefrontal connectivity while processing fear faces but negatively correlated with amygdalo–insular connectivity while processing fear and angry; and (d) negatively correlated with prefrontal gray matter volumes. These results suggest CM exposure may account for variability in limbic/prefrontal brain function and prefrontal structure in adulthood PTSD and offer one potential mechanism through which CM confers risk to future development of PTSD.     

Clinical predictors of early second event in patients with clinically isolated syndrome

This study aimed to determine the predictors of increased risk of a second demyelinating event within the first year of an initial demyelinating event (IDE) suggestive of early multiple sclerosis (MS). Patients with MS or clinically isolated syndrome (CIS) seen at the UCSF MS Center within one year of the IDE were studied. Univariate and multivariate Cox models were used to analyze predictors of having a second event within 1 year of the IDE. Of 330 patients with MS/CIS, 111 had a second event within 1 year. Non-white race/ethnicity (HR = 2.39, 95% CI [1.58, 3.60], p < 0.0001) and younger age (HR for each 10-year decrease in age = 1.51, 95% CI [1.28, 1.80], p < 0.0001) were strongly associated with an increased risk of having a second event within one year of onset. Having a lower number of functional systems affected by the IDE was also associated with an increased risk of early second event (HR for every one less FS involved = 1.31, 95% CI [1.06, 1.61], p = 0.011). These results were similar after adjusting for treatment of the IDE with steroids and disease-modifying therapy. Non-white race/ethnicity, younger age, and a lower number of FS affected by the IDE are associated with a substantially increased hazard ratio for a second demyelinating event within 1 year. Since early relapse is predictive of worse long-term outcome, identifying and treating such patients after the IDE may be of benefit to them.