Healthy donor effect and satisfaction with health: The role of selection effects related to blood donation behavior

The objective of this paper is to quantify selection effects related to blood donation behavior and their impact on donors' perceived health status. We rely on data from the 2009 and 2010 survey waves of the German socio-economic panel (N = 12,000), including information on health-related, demographic and psychographic factors as well as monetary donation behavior and volunteer work. We propose a propensity score matching approach to control for the healthy donor effect related to the health requirements for active blood donations. We estimate two separate models and quantify selection biases between (1) active and inactive blood donors and (2) active donors and non-donors. Our results reveal that active donors are more satisfied with their health status; after controlling for selection effects, however, the differences become non-significant, revealing selection biases of up to 82% compared with non-donors. These differences also exist between active and inactive donors, but the differences are less distinct. Our methodological approach reveals and quantifies selection biases attributable to the healthy donor effect. These biases are substantial enough to lead to erroneous statistical artifacts, implying that researchers should rigorously control for selection biases when comparing the health outcomes of different blood donor groups.

Increased gene expression of the cardiac endothelin system in obese mice

Obesity is a well-known risk factor of atherosclerosis and heart failure. In the human heart, a local endothelin system containing prepro-endothelin-1, endothelin-converting enzyme-1, and endothelin receptors A and B has been described. The endothelin system is activated in heart failure; however, the impact of obesity on the cardiac endothelin system is unknown. In this study, 18-week-old male C57BL/6 mice fed either a control diet or a high-fat diet for 10 weeks were analyzed. High-fat diet significantly increased the body weight of the animals and augmented low-density lipoprotein, high-density lipoprotein, and cholesterol plasma levels, compared to control. The animal groups showed no significant differences in left ventricular size or function (heart rate, ejection fraction, fractional shortening, left ventricular posterior wall thickness, cardiac output) after control or high-fat diet. We did not observe signs of cardiac hypertrophy or changes in markers of cardiac fibrosis in these heart samples. The cardiac expression of prepro-endothelin-1 mRNA, endothelin-converting enzyme-1 mRNA, and protein and endothelin receptors A and B mRNA was increased in 18-week-old obese C57BL/6 mice compared to animals with normal weight (p<0.05 vs. control). Furthermore, endothelin-1 plasma levels showed an increasing trend. In conclusion, an increased expression of genes of the endothelin system was observed in the hearts of 18-week-old mice after high-fat diet, possibly contributing to later cardiovascular complications of obesity.

Prevention of parastomal hernias with 3D funnel meshes in intraperitoneal onlay position by placement during initial stoma formation

PURPOSE

In patients with terminal ostomies, parastomal hernias (PSHs) occur on a frequent basis. They are commonly associated with various degrees of complaints and occasionally lead to life-threatening complications. Various strategies and measures have been tested and evaluated, but to date there is a lack of published evidence with regard to the best surgical technique for the prevention of PSH development.

METHODS

We conducted a retrospective analysis of prospectively collected data of eighty patients, who underwent elective permanent ostomy formation between 2009 and 2014 by means of prophylactic implantation of a three-dimensional (3D) funnel mesh in intraperitoneal onlay (IPOM) position.

RESULTS

PSH developed in three patients (3.75%). No mesh-related complications were encountered and none of the implants had to be removed. Ostomy-related complications had to be noted in seven (8.75%) cases. No manifestation of ostomy prolapse occurred. Follow-up time was a median 21 (range 3-47) months.

CONCLUSION

The prophylactical implantation of a specially shaped, 3D mesh implant in IPOM technique during initial formation of a terminal enterostomy is safe, highly efficient and comparatively easy to perform. As opposed to what can be achieved with flat or keyhole meshes, the inner boundary areas of the ostomy itself can be well covered and protected from the surging viscera with the 3D implants. At the same time, the vertical, tunnel-shaped part of the mesh provides sufficient protection from an ostomy prolapse. Further studies will be needed to compare the efficacy of various known approaches to PSH prevention.

Fragility fractures of the sacrum: how to identify and when to treat surgically?

The increasing prevalence of fragility fractures of the sacrum (FFS) occurring predominantly in osteoporotic individuals poses a diagnostic and therapeutic challenge. The clinical presentation varies from longstanding low back pain without the patient remembering a traumatic event to immobilized patients after suffering a low-energy trauma. FFS are often combined with a fracture of the anterior pelvic ring; hence they are classified as a part of fragility fractures of the pelvis (FFP). If not displaced, the patients are treated with weight bearing as tolerated and analgesics; however, we advocate to treat displaced fractures surgically according to the fracture personality and the patient’s comorbidities. Surgical options include minimal invasive sacro-iliac screws, trans-sacral bar osteosynthesis, open reduction and internal fixation, or spinopelvic stabilization. In the light of the high complication rate associated with immobilized patients, an operative approach often is indicated to accelerate the patient’s mobility.

Fragility fractures of the pelvis: should they be fixed?

Due to the aging population, there is an increasing number of fragility fractures of the pelvis (FFP). They are the result of low energy trauma. The bone breaks but the ligaments remain intact. Immobilizing pain at the pubic region or at the sacrum is the main symptom. Conventional radiographs reveal pubic rami fractures, but lesions of the dorsal pelvis are hardly visible and easily overlooked. CT of the pelvis with multiplanar reconstructions show the real extension of the lesion. Most patients have a history of osteoporosis or other fragility fractures. The new classification distinguishes between four categories of different and increasing instability. FFP Type I are anterior lesions only, FFP Type II are non-displaced posterior lesions, FFP Type III are displaced unilateral posterior lesions and FFP Type IV are displaced bilateral posterior lesions. Subgroups discriminate between the localization of the dorsal instability. FFP Type I lesions are treated non-operatively. FFP Type II lesions are fixed in a percutaneous procedure when a trial of conservative treatment was not successful. FFP Type III lesions are treated with open reduction and internal fixation (ORIF). FFP Type IV lesions are treated with bilateral ORIF or with a bridging osteosynthesis. Iliosacral screw osteosynthesis is widely used, but has an elevated risk of screw loosening due to diminished bine mineral density. Transsacral bar osteosynthesis enable interfragmentary compression and does not have this danger of loosening. Bridging plate osteosynthesis is used as an additional fixation to iliosacral screw osteosynthesis. Lumbopelvic fixation is restricted to highly unstable lumbopelvic dissociations. More studies are needed to find the optimal treatment for each type of instability. Key words: pelvis, fragility fracture, diagnosis, classification, treatment.

Intramedullary nailing after external fixation of the femur and tibia: a review of advantages and limits

PURPOSE AND METHODS

External fixation is a safe option for stabilisation of extremity lesions in the polytraumatised patient as well as in fractures with severe soft tissue damage. Nevertheless, long-term-complications are to be expected when external fixation is chosen as a definitive treatment. The purpose of this review article is twofold: primarily, to define the rationale of a procedural change from an external fixator to an intramedullary nail; secondarily, to assess the possible advantages and pitfalls of a single- or two-staged procedure.

RESULTS AND CONCLUSIONS

External fixation of the femur is recommended in multiply injured patients who are critically ill to avoid an additional inflammatory response caused by the surgical trauma of primary nailing. The conversion towards nailing must be done as soon as the clinical condition of the patient has been stabilised. Stable polytraumatised patients do not benefit from initial stabilisation with an external fixator and should immediately be treated with a definitive osteosynthesis. In tibial fractures, external fixation followed by intramedullary nailing is recommendable in fractures with severe soft tissue injuries. Conversion should be done as soon as the soft tissues allow before pin-tract infections occur and performed in a one-staged procedure.

[Curriculum for Practical Surgical Education during Internships - with a Strategy for New Perspectives]

BACKGROUND

It seems that the experience gained in the courses of surgical training in medical education does not really motivate students for surgery in Germany. Inspired by this problem the Department of Surgery of the Klinikum rechts der Isar, Technical University of Munich has developed a substantial reform for the internship since 2009 with the aim of not only improving the quality of education significantly, but also the attractiveness and thus the fascination for the subject.

METHODS

Based on the slogan "We want to awaken your fascination for surgery" a structured and standardised training of all students in their internship regardless of the ward or section and local conditions was developed. For this purpose a completely new curriculum was steadily implemented into clinical practice, based on the following four basic principles: (i) integration and perception in the clinic, (ii) central and peripheral maintenance, (iii) systematic and individual training, (iv) evaluation and feedback at all levels. To analyse the effectiveness of the reform, standardised evaluations by students and faculty were carried out regularly.

RESULTS

To date, since the beginning of the reform in 2009, there has been an approximately linear increase in the number of students in the PJ surgery. The daily systematic courses showed a good to excellent rating in all formats. The comparison showed a clear increasing trend in all the values, in particular, the "integration into the overall hospital" significantly improved (mean, 4.7 vs. 5.5, p = 0.003). However, the point "motivating for surgery" (mean, 3.3) remains at a low level. But also medical educators were satisfied with the new curriculum for the internship students (mean, 4.5).

CONCLUSION

The reform was adopted universally in a very positive manner and the current data support the need for such a reform. Overall, the reform showed a positive development of the internship training in the surgical department of the faculty. The satisfaction of the students and teachers could be increased by gradual implementation of the reform. Even if a lot of individual aspects gain a higher acceptance, the main concern, the inspiration of the "fascination" of the central surgical field, the training in the operating room, seems to succeed only partially.

[Patient Blood Management : three pillar strategy to improve outcome through avoidance of allogeneic blood products]

Blood transfusions are commonly viewed as life-saving interventions; however, current evidence shows that blood transfusions are associated with a significant increase of morbidity and mortality in a dose-dependent relationship. Not only explanatory models of basic research but also the results from randomized controlled trials suggest a causal relationship between blood transfusion and adverse outcome. Therefore, it can be claimed that the current state of science debunks the long held belief in the so-called life-saving blood transfusion by exposing the potential for promoting disease and death. Adherence to the precautionary principle and also the fact that blood transfusions are more costly than previously assumed require novel approaches in the treatment of anemia and bleeding. Patient Blood Management (PBM) allows transfusion rates to be dramatically reduced through correcting anemia by stimulating erythropoiesis, minimization of perioperative blood loss and harnessing and optimizing the physiological tolerance of anemia. A resolution of the World Health Assembly has endorsed PBM and therefore morbidity and mortality should be significantly reduced by lowering of the currently high blood utilization rate of allogeneic blood products in Austria, Germany and Switzerland.

Duplications in RB1CC1 are associated with schizophrenia; identification in large European sample sets

Schizophrenia (SCZ) is a severe and debilitating neuropsychiatric disorder with an estimated heritability of ~80%. Recently, de novo mutations, identified by next-generation sequencing (NGS) technology, have been suggested to contribute to the risk of developing SCZ. Although these studies show an overall excess of de novo mutations among patients compared with controls, it is not easy to pinpoint specific genes hit by de novo mutations as actually involved in the disease process. Importantly, support for a specific gene can be provided by the identification of additional alterations in several independent patients. We took advantage of existing genome-wide single-nucleotide polymorphism data sets to screen for deletions or duplications (copy number variations, CNVs) in genes previously implicated by NGS studies. Our approach was based on the observation that CNVs constitute part of the mutational spectrum in many human disease-associated genes. In a discovery step, we investigated whether CNVs in 55 candidate genes, suggested from NGS studies, were more frequent among 1637 patients compared with 1627 controls. Duplications in RB1CC1 were overrepresented among patients. This finding was followed-up in large, independent European sample sets. In the combined analysis, totaling 8461 patients and 112 871 controls, duplications in RB1CC1 were found to be associated with SCZ (P=1.29 × 10(-5); odds ratio=8.58). Our study provides evidence for rare duplications in RB1CC1 as a risk factor for SCZ.