Operative Volume of Newborn Surgery in German University Hospitals: High Volume Versus Low Volume Centers

Introduction Adequate patient volume is essential for the maintenance of quality, meaningful research, and training of the next generation of pediatric surgeons. The role of university hospitals is to fulfill these tasks at the highest possible level. Due to decentralization of pediatric surgical care during the last decades, there is a trend toward reduction of operative caseloads. The aim of this study was to assess the operative volume of the most relevant congenital malformations at German academic pediatric surgical institutions over the past years. Methods Nineteen chairpersons representing university-chairs in pediatric surgery in Germany submitted data on 10 index procedures regarding congenital malformations or neonatal abdominal emergencies over a 3-year period (2015 through 2017). All institutions were categorized according to the total number of respective cases into “high,” “medium,” and “low” volume centers by terciles. Some operative numbers were verified using data from health insurance companies, when available. Finally, the ratio of cumulative case load versus prevalence of the particular malformation was calculated for the study period. Results From 2015 through 2017, a total 2,162 newborns underwent surgery for congenital malformations and neonatal abdominal emergencies at German academic medical centers, representing 51% of all expected newborn cases nationwide. The median of cases per center within the study period was 101 (range 18–258). Four institutions (21%) were classified as “high volume” centers, four (21%) as “medium volume” centers, and 11 (58%) as “low volume” centers. The proportion of patients operated on in high-volume centers varied per disease category: esophageal atresia/tracheoesophageal fistula: 40%, duodenal atresia: 40%, small and large bowel atresia: 39%, anorectal malformations: 40%, congenital diaphragmatic hernia: 56%, gastroschisis: 39%, omphalocele: 41%, Hirschsprung disease: 45%, posterior urethral valves: 39%, and necrotizing enterocolitis (NEC)/focal intestinal perforation (FIP)/gastric perforation (GP): 45%. Conclusion This study provides a national benchmark for neonatal surgery performed in German university hospitals. The rarity of these cases highlights the difficulties for individual pediatric surgeons to gain adequate clinical and surgical experience and research capabilities. Therefore, a discussion on the centralization of care for these rare entities is necessary.

Evaluation of Low-kVp Low-Volume Iodinated Contrast Protocol for Coronary CT Angiography Using Retrospective ECG Gating

Objective The aim of this study was to evaluate the use of low peak kilovoltage (kVp) low-volume iodinated contrast protocol for performing coronary computed tomography (CT) angiography (CCTA) in patients using retrospective electrocardiogram (ECG) gating. Materials and Methods Hundred prospective patients undergoing CCTA were studied in two groups, A and B, using 70 kilovoltage (kV) and 120 kV protocols with half and standard intravenous volumes of injected iodinated contrast, respectively. All patients had heart rates less than 100 beats/min and body mass index (BMI) less than 31 kg/m2. Both the groups were evaluated for signal-to-noise (S/N) and contrast-to-noise (C/N) ratios along with radiation dose delivered in millisievert (mSv), and for image quality (IQ), on per patient and per segment basis. Results Patients with group A showed statistically reduced radiation dose of 1.86 mSv compared with 6.86 mSv in group B patients. Marked reduction in image noise with statistically improved S/N and C/N ratios in all coronary vessels was seen in group A. S/N ratios in group A were 20.25, 18.68, 19.04, 17.41, and 18.69 for aorta, left main, left anterior descending, right coronary, and left circumflex arteries while they were 13.34, 11.12, 10.96, 9.74, and 8.67 in group B patients. C/N ratios were also higher in all vessels in group A patients, that is, 19.48, 19.48, 19.04, 19.48, and 17.68, compared with group B patients, who had 12.43, 10.03, 9.23, 9.57, and 8.23 ratios (p < 0.0001). No significant difference in IQ per patient and per vessel was seen between both the groups. Discussion Retrospective ECG-gated low-kVp low-volume iodinated contrast protocol provides good diagnostic quality angiograms in patients with BMI up to 31 kg/m2 and with heart rates of less than 100 beats/min with three times reduced radiation dose. The reduced volume of contrast reduces the cost as well as the chance of contrast-induced nephropathy.

Towards Semi Automated Pre-assembly for Aircraft Interior Production

The growing aviation market puts first tier suppliers of aircraft interior under great pressure. Cabin monuments, not only consist of various assemblies with a wide range of parts, they are also highly customized by the airliners. Historically grown, poorly optimized manual processes offer the required flexibility, but limit the production rate of the individual products. The aviation industry responds with an increased use of automation technology. Recent standardization and automation approaches for efficient manufacturing, lead to an increase in productivity of these low volume products. However, complementary approaches to increase the degree of automation during assembly of aircraft interior components are missing. To reach a higher degree of automation this paper presents a derivation of cabin specific assembly processes with a varying degree of automation. First the range of components and processes in pre-assembly is analyzed with respect to automation. Based on the analysis, components and processes are classified in standardized groups. Fully automated and flexible automation processes are introduced to develop a semi-automated system. Furthermore, the required flow of information is described. Discussion of the results shows that the presented solution allows a flexible pre-assembly of low-volume interior parts and sets a baseline for further digitalization approaches.

Integrated Battery Chargers

Integrated battery chargers (IBCs) have been proposed as a low-weight, low-volume, and high-power solution to conventional conductive chargers. However, the design of such chargers is complicated, requiring special components or control techniques to solve inherent issues (such as galvanic isolation, torque generation, and system reconfiguration) associated with their design. Solutions vary based on charging power, drive topology, and motor technology. This chapter introduces designs for IBCs, including solutions as proposed in the literature. It also presents challenges in their industrial adoption. Finally, the chapter presents opportunities for fleet charging applications using IBCs.

Outcome of Aneurysmal Subarachnoid Hemorrhage in a Population‐Based Cohort: Retrospective Registry Study

BACKGROUND Studies of aneurysmal subarachnoid hemorrhage report an association between higher patient volumes and better outcomes. In regions with dispersed settlement, this must be balanced against the advantages with shorter prehospital transport times and timely access. The aim of this study is to report outcome for unselected aneurysmal subarachnoid hemorrhage cases from a well‐defined rural population treated in a low‐volume neurosurgical center. METHODS This is a retrospective, population‐based, observational cohort study from northern Norway (population 486 450). The University Hospital of North Norway provides the only neurosurgical service. We retrieved data for all aneurysmal subarachnoid hemorrhage cases (n=332) admitted during 2007 through 2019 from an institution‐specific register. The outcome measures were mortality rates and functional status assessed with the modified Rankin scale. RESULTS The mean annual number of cases was 26 (range, 16–38) and the mean crude incidence rate 5.4 per 100 000 person‐years. Two hundred seventy‐nine of 332 (84%) cases underwent aneurysm repair, 158 (47.5%) with endovascular techniques and 121 (36.4%) with microsurgical clipping, while 53 (15.9%) did not. The overall mortality rate was 16.0% at discharge and 23.8% at 12 months. The proportion with a favorable outcome (modified Rankin scale scores 0–2) was 36.1% at discharge and 51.5% at 12 months. In subgroup analysis of cases who underwent aneurysm repair, the mortality rate was 4.7% at discharge and 11.8% at 12 months, and the proportion with a favorable outcome 42.3% at discharge and 59.9% at 12 months. CONCLUSIONS We report satisfactory outcomes after treatment of aneurysmal subarachnoid hemorrhage in a low‐volume neurosurgical department serving a rural population. This indicates a reasonable balance between timely access to treatment and hospital case volume

Comparison of the activation capabilities of hemosorbents by adhesion rate of blood cells in vitro

Background: The relevance of the work lies in the search for new hemocontact drugs with hemocompatibility and a pronounced activation effect on the cellular and humoral blood systems for their possible use in clinical practice during low-volume hemoperfusion.The aim of this work was to assess the activation capabilities of three granular hemosorbents by the rate of adhesion of blood cellular elements to the surface of granules in vitro.Materials and methods. When using the method of low-volume hemoperfusion (LVH) in the clinic it is important to take into account the activation properties of solid-phase granular drugs. Blood-contact interaction was carried out in bench conditions with the use of donated blood in rotary mode. Blood samples were taken before the experiment and after 5, 20, 40 and 60 minutes. Changes in blood cell and subcellular populations were evaluated using the Sysmex XT 1800i hematological analyzer (26 parameters), which made it possible to indirectly judge the activation of blood cells. 30 experiments were conducted. To analyze the activation functions of the hemocontact preparations the speed-time adhesive profile of blood cells on the sorbent was used.Results. The effect of using the preparations Silochrome S-120 and SPS in comparison with SСT-6A HP as contact hemoactivators can be more pronounced, since the activation potential of these sorbents for blood cells is much higher. Silochrome S-120 has the highest activation capabilities compared to SPS and SKT-6A HP.Conclusion. Adhesion rate indicators can be indicators of the activation of blood cells upon contact with foreign surfaces and serve as a criterion for assessing the activation capabilities of these surfaces when using the LVH method in the clinic.