P996Early experience of transnasal micro-transesophageal echocardiography to guide left atrium appendage closure under conscious sedation

Introduction

Percutaneous left atrial appendage closure (LAAC) is typically performed utilizing transesophageal echocardiography (TEE) and fluoroscopy under general anesthesia (GA) or intracardiac echocardiography (ICE) under conscious sedation. Transnasal microtransesophageal echocardiography (micro-TEE) is a recently described technique to guide structural heart interventions eliminating the need for GA, which is beneficial for all, especially older patients. In this series, we report our initial experience with this novel technique to guide LAAC.

Methods and results

Between June 2018 and January 2019, we performed 30 consecutives LAAC (mean age 80,2 years old) with the Amplatzer AMULET in whom we considered using transnasal micro-TEE under conscious sedation instead of TEE under GA. All patients had a CT prior to the procedure to assess anatomy suitability and to rule out thrombus as well as a follow-up CT performed at 3 months post-LAAC to confirm complete sealing. Three patients had TEE instead of micro-TEE for various reasons (patient preference, cognitive impairment, INR >2). We observed one cross-over to TEE+GA because of a failed esophageal intubation under conscious sedation. Device implantation success rate was 100%. Imaging quality was quoted either good or excellent in 25 of the 26 patients with the remaining being quoted as suboptimal. Patient tolerance was either good or excellent in 24 of the 26 cases. There were five epistaxis noticed, one requiring nasal packing. No device embolization, no significant peri-device leak, no tamponade occurred in any patient during this period. At 3 months, there was no prosthesis thrombosis observed and 23% (6/26) had partial opacification of the LAA behind the prosthesis.

Conclusion

In this series, transnasal micro-TEE was feasible, safe, well tolerated and provided sufficient imaging quality to guide LAAC with the Amplatzer AMULET under conscious sedation. The cheaper cost and the wider field of view of micro-TEE over ICE are potential advantages that could impact the organization of LAAC programs especially when these interventions are planned in the elderly in whom GA carries a significant risk.

Influence of Membranes on Generation of β2 M and Release of Leukocyte Lysosomal Enzymes

Normal leukocyte functional capacity was investigated by evaluation of phagocytosis of opsonised yeast cells in a radiometric test system. After incubation with dialysis membranes (different cellulosic membranes, polysulfon membrane (PS), polymethylmetacrylate membrane (PMMN), the phagocytosis index, expressed as percent decrease with respect to initial values without membrane, decreased by 10%–25%. The most pronounced effect was observed with PS, cuprophane, modified cellulose and PMMA. The results are not related to differences in the viability of PMN during the test procedure; dead PMN amounted to about 4–6.5%. A significant increase in β-NAG and β-Gluc activities was released in the supernatants of the phagocytosis suspensions. This increase activity can be explained by the phagocytosis of PMN but it was not influenced by membrane contact. There was no influence of membrane contact or phagocytosis activity of PMN on the β2M concentration in the supernatant demonstrating that no in vitro generation during incubation with either membrane exists.

Serum Vitamin E Levels in Patients with Chronic Renal Failure

27 patients with chronic renal failure, 21 patients on chronic intermittend dialysis treatment and 27 healthy controls were tested for serum level of vitamin E estimated spectrophotometrically. Both patient groups had significant higher mean values (12.1 ± 1.2 and 7.2 ± 0.8 μg/ml respectively) in comparison with normal controls (4.6 ± 0.7 μg/ml). No correlation was found to serum creatinine, hematologic values, protein and lipoprotein concentration, nor to mode and duration of treatment regimes. Vitamin E was not extracted from blood throughout dialysis.

Under normal conditions of conservative or dialysis treatment of chronic renal failure patients vitamin E seems not to be a factor concerning uremic symptoms and there is no need for supplementation.

Prediction of Cardiovascular Risk in Hemodialysis Patients by Data Mining

Objectives: The objective of this work was to contribute to the development, validation and application of data mining methods for prediction in decision support systems in medicine. The particular focus was on the prediction of cardiovascular risk factors in hemodialysis patients, specifically the interventricular septum (IVS) thickness of the heart of individual patients as an important quantitative indicator to diagnose left ventricular hypertrophy. The work was based on data from 63 long-term hemodialysis patients of the KfH Dialysis Centre in Jena, Germany.

Methods: The approach applied is based on data mining methods and involves four major steps: data based clustering, cluster based rule extraction, rulebase construction and cluster and rule based prediction. The methods employed include crisp and fuzzy algorithms. At each step, logical and medical validation of results was carried out. Different sets of randomly selected patient data were used to train, test and optimize the clusterbases and rulebases for prediction.

Results: Using the best clusterbase/rulebase combination designed, the IVS thickness cluster (‘small’ or ‘large’) was predicted correctly for 30 of the 35 patients with known IVS values in the training data set; no patient was predicted incorrectly and 5 were parity predicted. For the test data set, 4 of the 6 patients with known IVS values were predicted correctly, no patient incorrectly and 2 parity. These results did not substantially differ from those obtained using the second best clusterbase/rulebase combination which was finally recommended for use based on further performance criteria. The prediction of the IVS thickness clusters of the 22 patients with unknown IVS values also yielded good results that were (and could only be) validated by a medical individual risk assessment of these patients.

Conclusions: The approach applied proved successful for the cluster and rule based prediction of a quantitative variable, such as IVS thickness, for individual patients from other variables relevant to the problem. The results obtained demonstrate the high potential of the approach and the methods developed and validated to support decision-making in hemodialysis and other fields of medicine by individual risk prediction.

[3D Fluoroscopy-Navigated Magerl Fusion of the 1st and 2nd Cervical Vertebra]

Background: Treatment of type II fractures of the odontoid process is still controversial. Besides conservative treatment, there are surgical options, including anterior screw fixation, as first described by Böhler and Magerl, or procedures using a dorsal approach. Many authors prefer dorsal fusion of C1 and 2, due to the reliable, biomechanical stability. In this context, pedicle screw fixation, as described by Harms, and transarticular screw fixation of the atlantoaxial joints, as described by Magerl, have to be mentioned. With the use of intraoperative fluoroscopic navigation, the risk of neurovascular lesions caused by abortive drilling or malposition of screws has been significantly decreased. In 1993, Eysel and Roosen established a subclassification of type II fractures of the odontoid process and gave treatment recommendations for each of the three subtypes. While there was an outcome for type A and B fractures treated by anterior screw fixation, the authors recommended performing dorsal stabilisation at type C fractures. Indication: In accordance with the recommendations of Eysel and Roosen, an 82 year old man, suffering from a type II C fracture of the odontoid process, underwent navigated, transarticular screw fixation of C1 and C2. Method: Once the 3D-fluoroscopy scan had been performed, the correct drilling direction in the axial, coronary and sagittal views of C1 and 2 was found using the navigated drillguide. After K-wires had been inserted in this direction on both sides, a second 3D-scan was performed to recontrol placement of the K-wires. Cannulated screws were introduced and the rods were installed, bearing the atlas hook to fixate the posterior atlas. Conclusion: In summary, dorsal, transarticular fusion of C1 and C2 is a successful treatment option, rarely leading to complications and is accompanied by reduced radiation exposure to the operating team.

[3D-Navigated Implantation of Pedicle Screws in the Cervical Spine - Experience and Analysis of Complications]

Background: Placing transpedicular screws in the cervical spine is a special challenge for spine surgeons, due to the anatomical features of this part of the spine. During the last 15 years, computer-aided navigation systems have been developed to facilitate this procedure and to make it safer for patients. One option is navigation by intraoperatively acquired data sets with the use of an 3D C-arm. Patients/Material and methods: Our retrospective study evaluates transpedicular screws in the cervical spine placed by 3D C-arm navigation, within a 6 year period in a level 1 trauma centre. We recorded epidemiological data, operation time and especially general adverse events, as well as revision surgery, including reasons for revision. We used a C-arm Arcardis Orbic 3D (Siemens, Munich), connected to a navigation system (VectorVision, Brainlab, Munich). Results: Between July 2007 and July 2013, 207 transpedicular screws were placed in 58 patients. The main indications were trauma (69 %), rheumatic diseases (20.7 %) and tumour (8.6 %). The most commonly instrumented cervical spine segments were C2 (53.5 %)%), C7 (10.3 %) and C5 (8.6 %). In nearly 95 % of the cases, we performed an intraoperative 3D scan after screw or k-wire placement to control the screw position. We found unacceptable malposition in 7.2 % of patients. This was corrected at once. Ten patients had to be revised: seven times due to wound problems, twice because of implant failure and once for treatment of CSF leakage. Three screws (1.5 %) led to injuries of the vertebral artery, once with a lethal outcome. Analysis of these cases showed that the 3D scan gave reduced data quality, due to reduced bone density or anatomical factors. Conclusion: Intraoperative 3D C-arm navigation seems to be a reliable option for transpedicular screw placement in the cervical spine. Complication rates were comparable to published values. 7.2 % of all screws were corrected intraoperatively after a control scan. Therefore possible revisions could be avoided during primary surgery. Analysis of problematic cases led to a change in our treatment strategy: in patients with poor bone quality and/or anatomical problems which lead to 3D scans of poor quality, we avoid transpedicular screw placement in C6 or higher, in order to prevent injuries of the vertebral artery.

[The biomechanics of hyperextension injuries of the subaxial cervical spine]

Hyperextension injuries of the subaxial cervical spine are potentially hazardous due to relevant destabilization. Depending on the clinical condition, neurologic or vascular damage may occur. Therefore an exact knowledge of the factors leading to destabilization is essential. In a biomechanical investigation, 10 fresh human cadaver cervical spine specimens were tested in a spine simulator. The tested segments were C4 to 7. In the first step, physiologic motion was investigated. Afterwards, the three steps of injury were dissection of the anterior longitudinal ligament, removal of the intervertebral disc/posterior longitudinal ligament, and dissection of the interspinous ligaments/ligamentum flavum. After each step, the mobility was determined. Regarding flexion and extension, an increase in motion of 8.36 % after the first step, 90.45 % after the second step, and 121.67 % after the last step was observed. Testing of lateral bending showed an increase of mobility of 7.88 %/27.48 %/33.23 %; axial rotation increased by 2.87 %/31.16 %/45.80 %. Isolated dissection of the anterior longitudinal ligament led to minor destabilization, whereas the intervertebral disc has to be seen as a major stabilizer of the cervical spine. Few finite-element studies showed comparable results. If a transfer to clinical use is undertaken, an isolated rupture of the anterior longitudinal ligament can be treated without surgical stabilization.

Use and Effectiveness of Continuous Subcutaneous Insulin Infusion (CSII) and Multiple Daily Insulin Injection Therapy (MIT) in Children, Adolescents and Young Adults with Type 1 Diabetes Mellitus

Today continuous subcutaneous insulin infusion (CSII) is frequently used in children and adolescents with type 1 diabetes mellitus. The present cross-sectional trial aimed to document current practice, quality of diabetes control and incidence of acute complications in different age-groups under CSII vs. multiple daily insulin injection therapy (MIT). Moreover the survey analyzed socio-demographic backgrounds of the patients.

PATIENTS AND METHODS

A total of 901 patients (age 11.5±4.0, diabetes duration 4.0±3.6 years) was entered in the database. Clinical data, laboratory parameters and, using a standardized questionnaire, socio-demographic data were assessed. For age-related analyses patients were allocated to 4 groups: pre-school children (< 6 years), pre-adolescents (≥ 6 and<11 years), adolescents (≥ 11 and<16 years) and young adults (≥ 16 and<22 years).

RESULTS

Of the cohort n=194 had a CSII, n=707 had a MIT. Patients with CSII vs. MIT had a longer diabetes duration, they used more frequently insulin analogues, performed more frequently blood-glucose self-tests and had a lower insulin dosage per kilogram body weight. In respect of HbA1c, the mean amplitude of blood-glucose excursions, but also of lipids, creatinine, microalbuminuria and blood pressure, there were no differences in neither age-group between patients with CSII and MIT. In patients with CSII and MIT, there was a tendency (p<0.05) towards an increase in HbA1c in adolescents and young adults and there was a decrease (p<0.05 for tendency) in the frequency of hypoglycaemia from the age group of young adults to pre-school children. Adolescents and young adults with CSII had a higher educational level. Pre-adolescents, adolescents and young adults with CSII have also better diabetes-related knowledge. Moreover, in all age-groups, the parents of patients with CSII had mostly a lower unemployment rate and higher educational levels.

CONCLUSIONS

The present analyses demonstrate that in all age-groups CSII provides convenient and flexible insulin delivery during routine treatment of type 1 diabetes. There is reasonable quality of diabetes control accompanied by a low incidence of hypoglycaemia and ketoacidosis. However, under CSII and MIT there is an increase of HbA1c towards adolescence. It must also highlighted that CSII seems to be expansive and that CSII is more frequently used in patients with better educational levels and deriving from higher social classes.

Inhibition of Cellular Adhesion by Immunological Targeting of Osteopontin Neoepitopes Generated through Matrix Metalloproteinase and Thrombin Cleavage

Osteopontin (OPN), a secreted protein involved in inflammatory processes and cancer, induces cell adhesion, migration, and activation of inflammatory pathways in various cell types. Cells bind OPN via integrins at a canonical RGD region in the full length form as well as to a contiguous cryptic site that some have shown is unmasked upon thrombin or matrix metalloproteinase cleavage. Thus, the adhesive capacity of osteopontin is enhanced by proteolytic cleavage that may occur in inflammatory conditions such as obesity, atherosclerosis, rheumatoid arthritis, tumor growth and metastasis. Our aim was to inhibit cellular adhesion to recombinant truncated proteins that correspond to the N-terminal cleavage products of thrombin- or matrix metalloproteinase-cleaved OPN in vitro. We specifically targeted the cryptic integrin binding site with monoclonal antibodies and antisera induced by peptide immunization of mice. HEK 293 cells adhered markedly stronger to truncated OPN proteins than to full length OPN. Without affecting cell binding to the full length form, the raised monoclonal antibodies specifically impeded cellular adhesion to the OPN fragments. Moreover, we show that the peptides used for immunization were able to induce antisera, which impeded adhesion either to all OPN forms, including the full-length form, or selectively to the corresponding truncated recombinant proteins. In conclusion, we developed immunological tools to selectively target functional properties of protease-cleaved OPN forms, which could find applications in treatment and prevention of various inflammatory diseases and cancers.

[Management of Idiopathic Frozen Shoulder - Prospective Evaluation of Mobilisation under Anaesthesia and an Additional Subacromial Cortisone Injection]

BACKGROUND

Management of primary frozen shoulder is still controversial. Many authors tend to treat patients with an arthroscopic release, if conservative therapy fails. We aimed to demonstrate the efficiency of manipulation under anaesthesia (MUA) in patients with primary frozen shoulder and to contrast the outcome of single MUA with the results of MUA with an additional subacromial injection of cortisone.

MATERIAL AND METHODS

A prospective trial with a 1-year follow-up was performed. Between 2008 and 2011 30 patients with idiopathic frozen shoulder underwent MUA, 15 of them received an additional injection of triamcinolone and bupivacain. Thereafter all patients underwent a standardised physiotherapy treatment regime for three months. The patients were assessed for pain, function, range of motion and the Constant-Murley score (CMS) before MUA as well as 1, 6 and 12 months after the intervention.

RESULTS

Range of motion increased significantly (p < 0.05) in all planes at every point of follow-up. Preinterventional abduction improved from 65.80° ± 13.25 to 145.40° ± 18.50, preinterventional forward flexion from 90.20° ± 18.98 to 155.60° ± 13.51 at 1 month after MUA. At this point 80 % of patients had returned to work, 66.7 % were free of pain. One year after MUA abduction was improved to 173.07° ± 6.03, forward flexion to 175.47° ± 4.03. The CMS rose significantly (p < 0.05) from 24.53 ± 9.28/100 to 73.97 ± 10.77/100 after 1 month and up to 86.30 ± 5.62/100 after 1 year. Range of motion and function as described for a healthy shoulder were recognised in every patient during 1 year. However additional subacromial injections of triamcinolone and bupivacain did not lead to a significant improvement. There were no complications reported.

CONCLUSION

This study demonstrates that MUA is a safe and effective tool in the management of idiopathic frozen shoulder, if conservative therapy fails. An additional subacromial injection of cortisone however does not generate a significant improvement.

Reactions of the rat musculoskeletal system to compressive spinal cord injury (SCI) and whole body vibration (WBV) therapy

Traumatic spinal cord injury (SCI) causes a loss of locomotor function with associated compromise of the musculo-skeletal system. Whole body vibration (WBV) is a potential therapy following SCI, but little is known about its effects on the musculo-skeletal system. Here, we examined locomotor recovery and the musculo-skeletal system after thoracic (T7-9) compression SCI in adult rats. Daily WBV was started at 1, 7, 14 and 28 days after injury (WBV1-WBV28 respectively) and continued over a 12-week post-injury period. Intact rats, rats with SCI but no WBV (sham-treated) and a group that received passive flexion and extension (PFE) of their hind limbs served as controls. Compared to sham-treated rats, neither WBV nor PFE improved motor function. Only WBV14 and PFE improved body support. In line with earlier studies we failed to detect signs of soleus muscle atrophy (weight, cross sectional diameter, total amount of fibers, mean fiber diameter) or bone loss in the femur (length, weight, bone mineral density). One possible explanation is that, despite of injury extent, the preservation of some axons in the white matter, in combination with quadripedal locomotion, may provide sufficient trophic and neuronal support for the musculoskeletal system.

Vitamin status in patients with chronic renal failure

Many factors complicate the effort for a recommendation on individual vitamin requirements in CRF. On the basis of our present incomplete knowledge about the handling of vitamins in uremia, suggestions for appropriate supplementation only of water-soluble vitamins are given. Patients with advanced CRF without dialysis treatment should receive daily supplements of vitamin B6 (5 mg), ascorbic acid (70-100 mg), and the normal recommended daily allowance of the other water-soluble vitamins in addition to the vitamin intake from the diet. We give folic acid only in patients taking antifolate drugs or in combination with iron in iron deficiency state and anemia (1 tablet of Folicombin contains 0.5 mg folic acid and 0.4 g elemental iron). There is still a pressing need for more data on the vitamin status, on vitamin requirements, and on long-term effects of vitamin administration in CRF.

[Rotating physician in CHIR-Net. Evaluation of the curriculum]

BACKGROUND

Conduction of and participation in clinical trials is a major challenge for surgical departments especially as job performance in hospitals has increased immensely during the last few years due to economic aspects. Only 11.7 % of published clinical studies are randomized controlled trials. As more and more treatment procedures in medicine have an evidence-based design the aim must be to present randomized controlled trials with an evidence level 1 for an increasing number of surgical therapies. Since 2006 the German National Surgical Trial Network (CHIR-Net) has been established and funded by the Federal Ministry of Education and Research (BMBF) in order to promote the realization of clinical trials in surgery. Thus the basis for the execution of high quality clinical studies in surgery has been extended further. In the individual CHIR-Net centers clinical trials are planned, organized and supervised which requires extensive knowledge of prevalent international standards. Teaching them to rotating physicians is one of the tasks of CHIR-Net. Therefore, a special curriculum for physicians has been developed which is evaluated in this study.

MATERIALS AND METHODS

From December 2010 to March 2011 an online survey of physicians who had previously rotated in the CHIR-Net was conducted, starting from the Surgical Regional Center (CRZ) Witten-Herdecke/Cologne. A total of 19 partly open and partly closed questions concerning the person, training, duration of the rotation, the funding applied for and the generated scientific output were surveyed. In addition, the curriculum for physicians and rotation time was checked by means of 17 questions in an evaluation matrix.

RESULTS

In this article the results of the rotating physician evaluation are presented. The satisfaction of physicians with the training during the rotation is presented as well as an analysis of how many of the submitted publications were directly supported by CHIR-Net. It was also evaluated how many rotating physicians requested funding and what the type of funding was.

CONCLUSION

With the rotating physician model of CHIR-Net a working concept for the training of surgeons in clinical research and the realization of randomized surgical trials was established as a viable solution for the difficult situation of clinical research in the surgical disciplines with the double burden of research and clinical practice.

Traction radiography for the diagnosis of scapholunate ligament tears: an experimental cadaver study

The aim of this experimental cadaver study was to verify that thumb traction radiography can be used to diagnose scapholunate interosseous ligament (SLIL) injury. Eight cadaver forearms were positioned vertically so that the thumb could be held in a Chinese finger trap and traction force applied using a 5 kg weight. Fluoroscopy was performed with the thumb unloaded and under traction, and then unloaded and under traction after division of the SLIL. The scapholunate joint gaps were measured electronically. The difference between the unloaded and loaded wrists with sectioned SLIL was not statistically significant. These results suggest that thumb traction radiography might not reliably detect acute, complete SLIL tears.

[Appearance of complex regional pain syndrome after intramedullary nailing of a clavicle fracture]

After operative correction of a clavicle fracture using an elastic stable intramedullary nail the patient presented signs of delayed fracture healing after 2 months. During the sixth postoperative month the 28-year-old obviously pain-ridden female patient showed dystonia of the shoulder girdle and allodynia surrounding the operation field. Upon these findings, we decided - as a result of the complex regional pain syndrome that had not been previously described in this location - to treat the patient by administering bisphosphonates, multimodal analgetic therapy, physiotherapy and occupational therapy. Fourteen months after surgery, the patient showed no remaining symptoms, and the fracture had consolidated at that time.

[Revision arthroplasty of the elbow]

Total elbow arthroplasty (TEA) is gaining in popularity. An elbow prosthesis is nowadays no longer regarded as a salvage procedure for low demand patients but is increasingly used in younger, active patients with higher demands. In elderly patients TEA is more and more accepted as a primary treatment method for osteoporotic complex distal humerus fractures. Nevertheless, TEA is technically demanding and associated with a higher complication and revision rate compared to e.g. hip prostheses. Increasing implantation rates in a juvenescent population will lead to a considerable increase in revision rates. Most common causes are aseptic and septic loosening as well as implant failure and instability. Cemented semi-constrained prostheses are mostly used for revision elbow arthroplasty. This article deals with the causes of revision elbow arthroplasty and describes the operative technique of revision of total elbow arthroplasty.