Michael Nerlich

Development of new reconstructive techniques: use of Integra in combination with fibrin glue and negative-pressure therapy for reconstruction of acute and chronic wounds.

Large wounds resulting from severe injuries are generally treated with extended reconstructive operations (e.g., free flaps), which are accompanied by long hospitalizations and risks of infection, thrombosis, and flap loss. Integra is a collagen template that can be used for reconstruction of defects. The take rate and the rate of infection are essential for the successful use of Integra (Johnson and Johnson, Hamburg, Germany). Whether the take rate and integration of Integra could be improved with the use of fibrin glue and negative-pressure therapy was assessed. Between January of 2002 and December of 2002, patients with large defects who underwent Integra grafting for reconstruction were randomly divided into groups receiving either a new treatment with fibrin glue-anchored Integra and postoperative negative-pressure therapy or conventional treatment. Demographic features, cause of the wound, location of the wound, take rate, complications of Integra coverage, time from Integra coverage to skin transplantation, and functional and aesthetic results were assessed. Twelve patients (with similar group distributions with respect to sex, age, and location and cause of the injury) were included in the study. The take rate was 78 ± 8 percent in the conventional treatment group and 98 ± 2 percent in the fibrin/negative-pressure therapy group (p < 0.003). The mean period from Integra coverage to skin transplantation was 24 ± 3 days in the conventional treatment group but only 10 ± 1 days in the fibrin/negative-pressure therapy group (p < 0.002). The decrease in the interval between coverage with Integra and skin transplantation resulted in shorter hospital stays. The use of fibrin glue and negative-pressure therapy in combination with Integra could shorten the period from coverage to integration, which would be beneficial in terms of decreased risks of infection, thrombosis, and catabolism. Therefore, it is suggested that Integra be used in combination with fibrin glue and negative-pressure therapy to improve clinical outcomes and shorten hospital stays, with decreased risks of accompanying complications.

Are Applied Growth Factors Able to Mimic the Positive Effects of Mesenchymal Stem Cells on the Regeneration of Meniscus in the Avascular Zone

Meniscal lesions in the avascular zone are still a problem in traumatology. Tissue Engineering approaches with mesenchymal stem cells (MSCs) showed successful regeneration of meniscal defects in the avascular zone. However, in daily clinical practice, a single stage regenerative treatment would be preferable for meniscus injuries. In particular, clinically applicable bioactive substances or isolated growth factors like platelet-rich plasma (PRP) or bone morphogenic protein 7 (BMP7) are in the focus of interest. In this study, the effects of PRP and BMP7 on the regeneration of avascular meniscal defects were evaluated. In vitro analysis showed that PRP secretes multiple growth factors over a period of 8 days. BMP7 enhances the collagen II deposition in an aggregate culture model of MSCs. However applied to meniscal defects PRP or BMP7 in combination with a hyaluronan collagen composite matrix failed to significantly improve meniscus healing in the avascular zone in a rabbit model after 3 months. Further information of the repair mechanism at the defect site is needed to develop special release systems or carriers for the appropriate application of growth factors to support biological augmentation of meniscus regeneration.

Diagnostic value of a hand-carried ultrasound device for free intra-abdominal fluid and organ lacerations in major trauma patients

Background Technological progress has led to the introduction of hand-carried ultrasound (HCU) imagers in clinical workflow. The aim of this study is to analyse whether examination with a HCU device is a rapid and reliable alternative to contrast-enhanced multidetector CT (MDCT) scans in diagnosis of free intra-abdominal fluid and organ lacerations in major trauma patients. Methods 31 major trauma patients with an injury severity score >15 and the necessity of a MDCT scan (standard of reference) were enrolled prospectively to this study, and additionally examined with a HCU, according to ‘focused assessment with sonography for trauma’ principles for the assessment of organ lacerations and free intra-abdominal fluid. The HCU device employed was of the latest generation. Statistical analysis was performed using PASW V.18. Results Four patients were diagnosed with free intra-abdominal fluid (prevalence 12.9%). HCU showed a sensitivity and specificity of 75% and 100%, respectively. Positive predictive value and negative predictive value were 100% and 96%, respectively. Five patients had organ lacerations (prevalence 16.1%). In these cases, the HCU was able to detect organ lacerations with a sensitivity and specificity of 80% and 100%, respectively. Therefore, a positive predictive value and negative predictive value of 100% and 96%, respectively, were calculated. Conclusion In major trauma patients, examination with HCU according to the ‘focused assessment with sonography for trauma’ principles for the diagnosis of organ lacerations and free intra-abdominal fluid is a reliable and rapid alternative to MDCT scans and can help save precious time in emergency situations, and should, additionally, be evaluated in the pre-clinical workflow.

Continuous lateral rotational therapy and systemic inflammatory response in posttraumatic acute lung injury: Results from a prospective randomised study

BACKGROUND The incidence of posttraumatic acute lung injury is high and may result in increased mortality. Changes in the body position are additional measures to improve pulmonary gas exchange and to prevent pulmonary complications. We investigated the effect of a continuous lateral rotational therapy (CLRT) on the inflammatory response in patients with posttraumatic lung failure. METHODS After admission to the intensive care unit (ICU) and after randomisation, 13 patients were placed in a special motor-driven bed and CLRT was performed for 5 days. In the control group (n=14), patients were positioned conventionally. Samples from blood and from broncho-alveolar lavage fluid (BAL) were collected in both groups before study began and on day 5. The levels of cytokines (Tumour Necrosis Factor, Interleukin 6, Interleukin 8 or Intercellular Adhesion Molecule-1) were assessed and haemodynamic, pulmonary, and laboratory values were documented. RESULTS On day 5, no significant differences were found in cytokine levels between groups, but a significant decrease in IL-8 (p<0.01) and TNF-α (p<0.05) serum levels and an increase in IL-8 BAL levels was found in the CLRT-group, but not for conventionally managed patients. In general cytokine BAL levels tended to be increased in both groups, but more pronounced during CLRT. Daily assessment of the severity of disease (SAPS-II, SOFA) was significantly reduced in the study group on days 2-4 (p<0.05) in comparison to control group. CONCLUSIONS CLRT may attenuate the inflammatory response to posttraumatic acute lung injury. The exact mechanism of such an effect is unknown.

Qualitätszirkel im TraumaNetzwerkD der DGU

ZusammenfassungKomplexe Abläufe und vielschichtige Probleme benötigen umfassende Lösungsansätze. Die Wirtschaft, speziell die Automobilindustrie, konnte zeigen, wie Qualitätsmanagement und Qualitätszirkel zu einer Verbesserung des Outcomes, insbesondere bei komplexen Problemen, beitragen können.Die Versorgung des Schwerverletzten (Polytrauma) stellt innerhalb der Medizin einen höchst komplexen Ablauf dar. Im Jahr 2006 forderte die Deutsche Gesellschaft für Unfallchirurgie durch das Weißbuch der Schwerverletztenversorgung, in dem die Strukturqualität der Polytraumata versorgenden Häuser festgeschrieben ist, dazu auf, TraumaNetzwerkeD zu bilden. Die traumatologisch aktiven Chefärzte der Kliniken Ostbayerns (einem Flächenstaat) schlossen sich, dem Ruf des Weißbuches folgend, zum Traumanetzwerk Ostbayern (TNO) zusammen. Während anfangs das Hauptaugenmerk darauf ruhte, die Zertifizierung zu erlangen (also die Strukturqualität in den jeweiligen Häusern den Vorgaben des Weißbuches anzugleichen), wandelte sich im Verlauf das Ziel mehr und mehr dahingehend, die Versorgungsqualität des polytraumatisierten Patienten über die Statuten hinaus innerhalb des Netzwerkes zu verbessern. Die Treffen der Chefärzte wurden zu einem Qualitätszirkel. Über ein standardisiertes Schockraumprotokoll, ein Feedback-Formular, einen Notarztfragebogen und insbesondere durch die Besprechungen von besonderen Fällen konnte nachhaltig die Qualität der Traumaversorgung in Ostbayern verbessert werden. Unstrittig ist, dass ein solcher, aus Chefärzten bestehender Qualitätszirkel, nur auf der Basis des Vertrauens und eines modernen Fehlermanagements bestehen kann.AbstractIn industry, especially in the automobile industry, improvements in efficiency could be demonstrated by quality management and quality circles. There is no doubt that in medicine, major trauma is also a very complex challenge.The German Association for Trauma Surgery published the White Paper on the Management of the Seriously Injured in 2006. The White Paper specifies the demand for quality of care, sets the level of structural requirements for trauma care and postulates the cooperation of regional hospitals within a network of dedicated trauma centres. The Trauma Network Eastern Bavaria (TNO) was the first certified trauma network in Germany. One of the reasons for this success is the fact that cooperation between trauma surgeons has already had a long tradition in this geographic area. The key factor is communication which is supported by all technical and organisational means. The formal installation of quality circles on each level of trauma care, e.g. within and across institutions, was accepted by all partners within the network. The goal is the improvement of patient care in trauma above and beyond the guidelines of the White Paper. This paper shows the instruments used to enhance the quality of trauma care within a network.In industry, especially in the automobile industry, improvements in efficiency could be demonstrated by quality management and quality circles. There is no doubt that in medicine, major trauma is also a very complex challenge.The German Association for Trauma Surgery published the White Paper on the Management of the Seriously Injured in 2006. The White Paper specifies the demand for quality of care, sets the level of structural requirements for trauma care and postulates the cooperation of regional hospitals within a network of dedicated trauma centres. The Trauma Network Eastern Bavaria (TNO) was the first certified trauma network in Germany. One of the reasons for this success is the fact that cooperation between trauma surgeons has already had a long tradition in this geographic area. The key factor is communication which is supported by all technical and organisational means. The formal installation of quality circles on each level of trauma care, e.g. within and across institutions, was accepted by all partners within the network. The goal is the improvement of patient care in trauma above and beyond the guidelines of the White Paper. This paper shows the instruments used to enhance the quality of trauma care within a network.

Post-traumatic fulminant paradoxical fat embolism syndrome in conjunction with asymptomatic atrial septal defect: a case report and review of the literature

IntroductionFat embolism syndrome with respiratory failure after intramedullary nailing of a femur fracture is a rare but serious complication in trauma patients.Case presentationWe present the case of a 20-year-old Caucasian man who experienced paradoxical cerebral fat embolism syndrome with fulminant progression after intramedullary nailing of a femur fracture, in conjunction with a clinically asymptomatic atrial septal defect in a high position resulting in a right-to-left shunt.ConclusionFat embolism syndrome may occur as a fulminant complication following femoral fracture repair in the presence of a concomitant atrial septal defect with right-to-left shunt. Thus, in patients with cardiac right-to-left shunts, femurs should not be nailed intramedullary, not even in cases of isolated injuries.

Operative Versorgung einer Acetabulumfraktur in der Schwangerschaft

ZusammenfassungWir berichten über eine Patientin, die sich, in der 23.Woche schwanger, im Rahmen eines Verkehrsunfalls eine Acetabulumfraktur zuzog, die 6 Tage nach Trauma operativ versorgt wurde; 1 1/2 Jahre nach dem Unfall ist die Mutter klinisch beschwerdefrei, das Kind entwickelte sich unauffällig und es besteht keinerlei Anhalt für eine Schädigung.Aufgrund dieses Falls sowie der entsprechenden Literatur sehen wir die operative Versorgung einer Acetabulumfraktur in der Schwangerschaft bei bestehender Indikation als die Methode der Wahl an, da sie für die Mutter zweifellos die beste Behandlung darstellt und gleichzeitig für Mutter und Kind mit nur minimalem Risiko einhergeht.AbstractWe report about a case of a pregnant women in the 23rd gestation week who sustained an isolated acetabular fracture in a car accident. The fracture was treated surgically by open reduction and internal fixation 6 days after trauma.The outcome for the mother and the baby was excellent; both could be followed up for 1.5 years.The baby did not suffer from any disease related to the diagnostic or surgical procedures.We conclude from this case and from reviewing the literature that the operative fixation of an acetabular fracture during pregnancy is the appropriate treatment with minimal risk for the unborn child and best outcome for the mother.

Autologous mesenchymal stem cells or meniscal cells: what is the best cell source for regenerative meniscus treatment in an early osteoarthritis situation?

BackgroundTreatment of meniscus tears within the avascular region represents a significant challenge, particularly in a situation of early osteoarthritis. Cell-based tissue engineering approaches have shown promising results. However, studies have not found a consensus on the appropriate autologous cell source in a clinical situation, specifically in a challenging degenerative environment. The present study sought to evaluate the appropriate cell source for autologous meniscal repair in a demanding setting of early osteoarthritis.MethodsA rabbit model was used to test autologous meniscal repair. Bone marrow and medial menisci were harvested 4 weeks prior to surgery. Bone marrow-derived mesenchymal stem cells (MSCs) and meniscal cells were isolated, expanded, and seeded onto collagen-hyaluronan scaffolds before implantation. A punch defect model was performed on the lateral meniscus and then a cell-seeded scaffold was press-fit into the defect. Following 6 or 12 weeks, gross joint morphology and OARSI grade were assessed, and menisci were harvested for macroscopic, histological, and immunohistochemical evaluation using a validated meniscus scoring system. In conjunction, human meniscal cells isolated from non-repairable bucket handle tears and human MSCs were expanded and, using the pellet culture model, assessed for their meniscus-like potential in a translational setting through collagen type I and II immunostaining, collagen type II enzyme-linked immunosorbent assay (ELISA), and gene expression analysis.ResultsAfter resections of the medial menisci, all knees showed early osteoarthritic changes (average OARSI grade 3.1). However, successful repair of meniscus punch defects was performed using either meniscal cells or MSCs. Gross joint assessment demonstrated donor site morbidity for meniscal cell treatment. Furthermore, human MSCs had significantly increased collagen type II gene expression and production compared to meniscal cells (p < 0.05).ConclusionsThe regenerative potential of the meniscus by an autologous cell-based tissue engineering approach was shown even in a challenging setting of early osteoarthritis. Autologous MSCs and meniscal cells were found to have improved meniscal healing in an animal model, thus demonstrating their feasibility in a clinical setting. However, donor site morbidity, reduced availability, and reduced chondrogenic differentiation of human meniscal cells from debris of meniscal tears favors autologous MSCs for clinical use for cell-based meniscus regeneration.

Platelet-Rich Plasma as an Autologous and Proangiogenic Cell Delivery System

Angiogenesis is a key factor in early stages of wound healing and is crucial for the repair of vascularized tissues such as the bone. However, supporting timely revascularization of the defect site still presents a clinical challenge. Tissue engineering approaches delivering endothelial cells or prevascularized constructs may overcome this problem. In the current study, we investigated platelet-rich plasma (PRP) gels as autologous, injectable cell delivery systems for prevascularized constructs. PRP was produced from human thrombocyte concentrates. GFP-expressing human umbilical vein endothelial cells (HUVECs) and human bone marrow-derived mesenchymal stem cells (MSCs) were encapsulated in PRP gels in different proportions. The formation of cellular networks was assessed over 14 days by time-lapse microscopy, gene expression analysis, and immunohistology. PRP gels presented a favorable environment for the formation of a three-dimensional (3D) cellular network. The formation of these networks was apparent as early as 3 days after seeding. Networks increased in complexity and branching over time but were only stable in HUVEC-MSC cocultures. The high cell viability together with the 3D capillary-like networks observed at early time points suggests that PRP can be used as an autologous and proangiogenic cell delivery system for the repair of vascularized tissues such as the bone.

Trauma care inside and outside business hours: comparison of process quality and outcome indicators in a German level-1 trauma center

BackgroundOptimal care of multiple trauma patients has to be at a high level around the clock. Trauma care algorithms and guidelines are available, yet it remains unclear if the time of admission to the trauma room affects the quality of care and outcomes. Hence the present study intends to compare the quality of trauma room care of multiple severely injured patients at a level-1 trauma center depending on the time of admission.MethodsA total of 394 multiple trauma patients with an ISS ≥ 16 were included into this study (observation period: 52 months). Patients were grouped by the time and date of their admission to the trauma room [business hours (BH): weekdays from 8:00 a.m. to 4:00 p.m. vs. non-business hours (NBH): outside BH]. The study analysed differences in patient demographics, trauma room treatment and outcome.ResultsThe study sample was comparable in all basic characteristics [mean ISS: 32.3 ± 14.3 (BH) vs. 32.6 ± 14.4 (NBH), p = 0.853; mean age: 40.8 ± 21.0 (BH) vs. 37.7 ± 20.2 years (NBH), p = 0.278]. Similar values were found for the time needed for single interventions, like arterial access [4.8 ± 3.9 min (BH) vs. 4.9 ± 3.4 min (NBH), p = 0.496] and quality-assessment parameters, like time until CT [28.5 ± 18.7 min (BH), vs. 27.3 ± 9.5) min (NBH), p = 0.637]. There was no difference for the 24 h mortality and overall hospital mortality in BH and NBH, with 13.5% vs. 9.1% (p = 0.206) and, 21.9% vs. 15.4% (p = 0.144), respectively. The Glasgow Outcome Scale (GOS) comparison revealed no difference [3.7 ± 1.6 (BH) vs. 3.9 ± 1.5 (NBH), p = 0.305]. In general, the observed demographic, injury severity, care quality and outcome parameters revealed no significant difference between the two time periods BH and NBH.ConclusionsThe study hospital provides multiple trauma patient care at comparable quality irrespective of time of admission to the trauma room. These results might be attributable to the standardization of the treatment process using established principles, algorithms and guidelines as well as to the resources available in a level-1 trauma center.