Bielefeld, Germany
Bielefeld, Germany

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Rahe-Meyer N.,Franziskus Hospital | Rahe-Meyer N.,Hannover Medical School | Solomon C.,Salzburger Landeskliniken SALK | Solomon C.,Hannover Medical School | And 9 more authors.
Anesthesiology | Year: 2013

Background: Fibrinogen is suggested to play an important role in managing major bleeding. However, clinical evidence regarding the effect of fibrinogen concentrate (derived from human plasma) on transfusion is limited. The authors assessed whether fibrinogen concentrate can reduce blood transfusion when given as intraoperative, targeted, first-line hemostatic therapy in bleeding patients undergoing aortic replacement surgery. METHODS: In this single-center, prospective, placebo-controlled, double-blind study, patients aged 18 yr or older undergoing elective thoracic or thoracoabdominal aortic replacement surgery involving cardiopulmonary bypass were randomized to fibrinogen concentrate or placebo, administered intraoperatively. Study medication was given if patients had clinically relevant coagulopathic bleeding immediately after removal from cardiopulmonary bypass and completion of surgical hemostasis. Dosing was individualized using the fibrin-based thromboelastometry test. If bleeding continued, a standardized transfusion protocol was followed. RESULTS: Twenty-nine patients in the fibrinogen concentrate group and 32 patients in the placebo group were eligible for the efficacy analysis. During the first 24 h after the administration of study medication, patients in the fibrinogen concentrate group received fewer allogeneic blood components than did patients in the placebo group (median, 2 vs. 13 U; P < 0.001; primary endpoint). Total avoidance of transfusion was achieved in 13 (45%) of 29 patients in the fibrinogen concentrate group, whereas 32 (100%) of 32 patients in the placebo group received transfusion (P < 0.001). There was no observed safety concern with using fibrinogen concentrate during aortic surgery. CONCLUSIONS: Hemostatic therapy with fibrinogen concentrate in patients undergoing aortic surgery significantly reduced the transfusion of allogeneic blood products. Larger multicenter studies are necessary to confirm the role of fibrinogen concentrate in the management of perioperative bleeding in patients with life-threatening coagulopathy. Copyright © 2012, the American Society of Anesthesiologists, Inc. Lippincott Williams & Wilkins.


Solomon C.,Salzburger Landeskliniken SALK | Solomon C.,Hannover Medical School | Rahe-Meyer N.,Hannover Medical School | Rahe-Meyer N.,Franziskus Hospital | Sorensen B.,King's College London
Thrombosis Research | Year: 2011

Introduction: Cardiac surgery performed on cardio-pulmonary bypass (CPB) may be complicated by coagulopathy and bleeding. This prospective observational study investigated the CPB-induced changes in thrombin generation, fibrin formation, and in the platelet component of the whole blood clot elasticity. The effects of haemostatic therapy with fresh frozen plasma (FFP) and platelet concentrate on these parameters were also evaluated. Materials and Methods: In 90 cardiac surgery patients, thrombin generation was measured using the calibrated automated thrombogram, fibrin formation was assessed as the maximum clot elasticity of the fibrin-based clot in the thromboelastometry FIBTEM test (MCE FIBTEM), and the platelet component was defined as the difference in maximum elasticity between the whole blood clot obtained through extrinsic activation and the fibrin-based clot (MCE EXTEM-MCE FIBTEM). Blood samples were collected before surgery, immediately after CPB, and after administration of FFP or FFP and platelet concentrate. Results: Following CPB, the endogenous thrombin potential decreased to 93%, from median 1485 (interquartile range 1207, 1777) to 1382 (1190, 1533) nM*min (P > 0.05), MCE FIBTEM decreased to 62%, from 21 (19, 29) to 14 (12, 19) (P < 0.001), and the platelet component to 73%, from 139 (119, 174) to 101 (87, 121) (P < 0.001). Administration of 11 (10, 13) ml per kg of bodyweight (ml/kgbw) FFP (40 patients), or of 13 (10, 18) ml/kgbw FFP and 7 (5, 9) ml/kgbw platelet concentrate (18 patients) brought no statistically significant changes in these parameters. Conclusions: Fibrin formation is more impaired than thrombin generation and the platelet component of the whole blood clot immediately after cardiopulmonary bypass. © 2011 Published by Elsevier Ltd.


Wojcinski S.,Hannover Medical School | Degenhardt F.,Franziskus Hospital | Peisker U.,Hermann Joseph Hospital | Beussel S.,Albert Ludwigs University of Freiburg | Hahn M.,University Hospital of Tuebingen
Ultraschall in der Medizin | Year: 2014

Purpose: Sonoelastography of the breast is an emerging technology with evident data in the literature suggesting diagnostic advantages. Our study investigates the current usage of sonoelastography among German DEGUM-certified breast ultrasound specialists. Materials and Methods: We used a standardized questionnaire with 18 items. In 2012, the survey was sent to all members of the breast ultrasound section of the DEGUM (n=654). Results: The group of survey participants (n=208) performs 193025 breast ultrasound examinations and examines 20110 breast cancers per year. 21.2% of the participants in the survey use sonoelastography, mainly for diagnostic purposes in BI-RADS®-US 3 and 4 lesions, less often for other categories or under study conditions. The most commonly applied criteria for the evaluation of the elastogram are the Tsukuba Elasticity Score (43.2%), the fat-lesion ratio (29.5%) and the determination of tissue stiffness with shear wave elastography expressed in kilopascal (25.0%). The majority of non-users of elastography (58.6%) would like to have the option of using sonoelastography in the future. Conclusion: Sonoelastography is a feasible and helpful method in the evaluation of breast lesions. A significant number of German ultrasound specialists already apply this technology today. We expect a growing number of sonographers to perform sonoelastography in the near future, provided that they have the necessary ultrasound system and that they are trained in the method. Evidence from the literature and the recommendations of the medical societies support this development. © Georg Thieme Verlag KG Stuttgart. New York.


Thomas A.,Charité - Medical University of Berlin | Degenhardt F.,Franziskus Hospital | Farrokh A.,Franziskus Hospital | Wojcinski S.,Franziskus Hospital | And 2 more authors.
Academic Radiology | Year: 2010

Rationale and Objectives: Initial data suggest that elastography can improve the specificity of ultrasound in differentiating benign and malignant breast lesions. The aim of this study was to compare elastography and B-mode ultrasound to determine whether the calculation of strain ratios (SRs) can further improve the differentiation of focal breast lesions. Materials and Methods: A total of 227 women with histologically proven focal breast lesions (113 benign, 114 malignant) were included at two German breast centers. The women underwent a standardized ultrasound procedure using a high-end ultrasound system with a 9-MHz broadband linear transducer. B-mode scans and sonoelastograms were analyzed by two experienced readers using the Breast Imaging Reporting and Data System criteria. SRs were calculated from a tumor-adjusted region of interest (mean color pixel density) and a comparable region of interest placed in the lateral fatty tissue. Sensitivity, specificity, and cutoff values were calculated for SRs (receiver-operating characteristic analysis). Results: The women had a mean age of 54 years (range, 19-87 years). The mean lesion diameter was 1.6 ± 0.9 cm. Sensitivity and specificity were 96% and 56% for B-mode scanning, 81% and 89% for elastography, and 90% and 89% for SRs. An SR cutoff value of 2.45 (area under the curve, 0.949) allowed significant differentiation (P < .001) of malignant (mean, 5.1 ± 4.2) and benign (mean, 1.6 ± 1.0) lesions. The quantitative method of SR calculation was superior to subjective interpretation of sonoelastograms and B-mode scans, with a positive predictive value of 89% compared to 68% and 84% for the other two methods. Conclusions: Calculation of SRs contributes to the standardization of sonoelastography with high sensitivity and allows significant differentiation of benign and malignant breast lesions with higher specificity compared to B-mode ultrasound but not elastography. © 2010 AUR.


Rahe-Meyer N.,Franziskus Hospital | Rahe-Meyer N.,Hannover Medical School | Hanke A.,Hannover Medical School | Schmidt D.S.,CSL Behring | And 3 more authors.
Journal of Thoracic and Cardiovascular Surgery | Year: 2013

Objectives: We assessed whether fibrinogen concentrate as targeted first-line hemostatic therapy was more effective than placebo or a standardized transfusion algorithm in controlling coagulopathic bleeding in patients undergoing major aortic surgery. Methods: In this single-center, prospective, double-blind study, adults undergoing elective thoracic or thoracoabdominal aortic replacement surgery involving cardiopulmonary bypass were randomized to intraoperative fibrinogen concentrate (n = 29) or placebo (n = 32). Study medication was given if patients had clinically relevant coagulopathic bleeding, measured by 5-minute bleeding mass, after cardiopulmonary bypass removal, protamine administration, and surgical hemostasis. Fibrinogen concentrate dosing was individualized using the thromboelastometric FIBTEM test. If bleeding continued, a standardized transfusion algorithm was followed. In the placebo group, all 32 patients received 1 transfusion cycle of fresh-frozen plasma/platelets, and 30 patients required a second transfusion cycle; none of these patients received any other procoagulant therapy. Change in bleeding rate after treatment was compared using t tests. Results: Mean change in bleeding rate after fibrinogen concentrate was -48.3 g/5 min, compared with 0.4 g/5 min after placebo (P < .001), -16.1 g/5 min after 1 transfusion cycle (fresh-frozen plasma or platelets; P =.003), and -28.0 g/5 min after 2 transfusion cycles (fresh-frozen plasma and platelets; P =.11). Reductions in bleeding rate were greater for patients with higher bleeding rates before treatment, especially with fibrinogen concentrate. Conclusions: FIBTEM-guided intraoperative hemostatic therapy with fibrinogen concentrate is more effective than placebo in controlling coagulopathic bleeding during major aortic replacement surgery. Fibrinogen concentrate is also more effective than 1 cycle of fresh-frozen plasma/platelets and is more rapid than - and at least as effective as - 2 cycles of fresh-frozen plasma/platelets. Copyright © 2013 Published by Elsevier Inc. on behalf of The American Association for Thoracic Surgery.


Solomon C.,University of Salzburg | Hagl C.,Hannover Medical School | Hagl C.,Ludwig Maximilians University of Munich | Rahe-Meyer N.,Hannover Medical School | Rahe-Meyer N.,Franziskus Hospital
British Journal of Anaesthesia | Year: 2013

Background There is currently a contrast between the demonstrated benefits of fibrinogen concentrate in correcting bleeding and reducing transfusion, and its perceived thrombogenic potential. This analysis evaluates the effects of fibrinogen concentrate on coagulation up to 12 days after administration during aortic surgery. Methods We performed a post hoc analysis of a prospective, randomized, double-blind, controlled trial of fibrinogen concentrate as first-line haemostatic therapy in aortic surgery. After cardiopulmonary bypass (CPB) and protamine administration, subjects with coagulopathic bleeding received fibrinogen concentrate or placebo. The placebo group received allogeneic blood products, including fresh-frozen plasma (FFP; n=32); the fibrinogen concentrate group received fibrinogen concentrate alone (FC; n=14), or fibrinogen concentrate followed by allogeneic blood products (FC+FFP; n=15). Plasma fibrinogen, fibrin-based clotting (ROTEM®-based FIBTEM assay), and peri- and postoperative haematological and coagulation parameters were compared. Results Plasma fibrinogen and FIBTEM maximum clot firmness (MCF) decreased ∼50% during CPB but were corrected by FC or FC+FFP. At last suture, the highest values for plasma fibrinogen (360 mg dl-1) and FIBTEM MCF (22 mm) were within normal ranges - below the acute phase increases observed after surgery. In patients receiving only FFP as a source of fibrinogen, these parameters recovered marginally by last suture (P<0.001 vs FC and FC+FFP). All groups displayed comparable haemostasis at 24 h post-surgery. Fibrinogen concentrate did not cause alterations of other haemostasis parameters. Conclusions Fibrinogen concentrate provided specific, significant, short-lived increases in plasma fibrinogen and fibrin-based clot firmness after aortic surgery. © 2013 The Author. Published by Oxford University Press on behalf of the British Journal of Anaesthesia.


Wojcinski S.,Hannover Medical School | Brandhorst K.,Franziskus Hospital | Sadigh G.,Emory University | Hillemanns P.,Hannover Medical School | Degenhardt F.,Franziskus Hospital
Ultrasound in Medicine and Biology | Year: 2013

Acoustic radiation force impulse imaging (ARFI) with Virtual Touch tissue quantification (VTTQ) enables the determination of shear wave velocity in meters per second (m/s). We investigated shear wave velocity in normal breast tissue and analyzed the influence of the degree of pre-compression on the measurements. In repeated measurements and with normal pre-compression, the mean shear wave velocity in breast parenchyma was significantly higher than that in breast adipose tissue (3.33±1.18m/s vs. 2.90±1.10m/s; p < 0.001; 712 measurements in 89 patients). Furthermore, we found a significant positive correlation between degree of pre-compression and velocity measurements. Shear wave velocities with low, moderate and high pre-compression were 1.89, 3.18 and 4.39m/s in parenchyma, compared with 1.46, 2.55 and 3.64m/s in adipose tissue, respectively (p<0.001; 360 measurements in 60 patients). VTTQ of breast tissue is a feasible method with high accuracy; however, the degree of pre-compression applied may significantly influence the measurements. © 2013 World Federation for Ultrasound in Medicine & Biology.


Wojcinski S.,Hannover Medical School | Boehme E.,Franziskus Hospital | Farrokh A.,Franziskus Hospital | Soergel P.,Hannover Medical School | And 2 more authors.
BMC Cancer | Year: 2013

Background: Lesions of the breast that are classified BI-RADS®-US 3 by ultrasound are probably benign and observation is recommended, although malignancy may occasionally occur. In our study, we focus exclusively on BI-RADS®-US 3 lesions and hypothesize that sonoelastography as an adjunct to conventional ultrasound can identify a high-risk-group and a low-risk-group within these patients. Methods: A group of 177 breast lesions that were classified BI-RADS®-US 3 were additionally examined with real-time sonoelastography. Elastograms were evaluated according to the Tsukuba Elasticity Score. Pretest and posttest probability of disease (POD), sensitivity (SE), specificity (SP), positive (PPV) and negative predictive values (NPV) and likelihood-ratios (LR) were calculated. Furthermore, we analyzed the false-negative and false-positive cases and performed a model calculation to determine how elastography could affect the proceedings in population screening. Results: In our collection of BI-RADS®-US 3 cases there were 169 benign and eight malignant lesions. The pretest POD was 4.5% (95% confidence interval (CI): 2.1-9.0). In patients with a suspicious elastogram (high-risk group), the posttest POD was significantly higher (13.2%, p = 0.041) and the positive LR was 3.2 (95% CI: 1.7-5.9). With a benign elastogram (low-risk group), the posttest POD decreased to 2.2%. SE, SP, PPV and NPV for sonoelastography in BI-RADS®-US 3 lesions were 62.5% (95% CI: 25.9-89.8), 80.5% (95% CI: 73.5-86.0), 13.2% (95% CI: 5.0-28.9) and 97.8% (95% CI: 93.3-99.4), respectively. Conclusions: Sonoelastography yields additional diagnostic information in the evaluation of BI-RADS®-US 3 lesions of the breast. The examiner can identify a low-risk group that can be vigilantly observed and a high-risk group that should receive immediate biopsy due to an elevated breast cancer risk. © 2013 Wojcinski et al.; licensee BioMed Central Ltd.


Purpose: The aim of this study was to evaluate the strain ratio measurement of breast lesions, to calculate the diagnostic value and to provide practically oriented recommendations concerning execution. Materials and Methods: 117 breast lesions in 98 patients were included in the study. All lesions were examined by B-mode ultrasound and elastography using strain ratio measurement. The preinterventional findings of the different methods were compared to the final histopathological results. The sensitivity, specificity, positive and negative predictive value and the diagnostic accuracy were calculated for each method. Results: There was a significant difference between the strain ratio of malignant (mean 6.50; sd 3.03; 95 %-CI 5.68 7.33) and benign (mean 1.79; sd 3.83; 95 %-CI 0.92 2.75) lesions. The strain ratio showed a sensitivity of 92.6 % (95 %-CI 82.1 97.9) and a specificity of 95.2 % (95 %-CI 86.7 99.0). The positive and negative predictive values were 94.3 % and 93.7 %. B-mode ultrasound achieved a sensitivity of 94.4 % (95 %-CI 84.6 98.8) and a specificity of 87.3 % (95 %-CI 76.5 94.3). The positive and negative predictive values were 86.4 % and 94.8 %. Conclusion: Strain ratio measurement of breast lesions is a standardized fast method for analyzing the stiffness inside the examined areas. Used as an additional tool to B-mode ultrasound, it helps to increase the specificity of the examination. © Georg Thieme Verlag KG Stuttgart - New York.


Bahm J.,Franziskus hospital
Journal of Brachial Plexus and Peripheral Nerve Injury | Year: 2013

We present two children with a diagnosis of upper limb arthrogryposis and report on findings about brachial plexus exploration and a nerve transfer procedure to reanimate elbow flexion. Although the etiology of arthrogryposis multiplex congenita remains unknown and multifactorial, it can be worthful to explore the brachial plexus in the affected upper limb and to perform selective motor nerve transfers on morphologically well developed but not sufficiently innervated target muscles, like the biceps brachialis, brachialis, deltoid and supra-/infraspinatus muscles. This strategy may reduce the necessity of later muscle transfers and improves the overall functional status of the affected limb(s). © 2013 Bahm; licensee BioMed Central Ltd.

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