Ten-year follow-up and clinical outcome of a metaphyseal anchoring short hip stem prosthesis: a retrospective single-centre analysis.

PURPOSE: Short stems for total hip arthroplasty are an alternative to traditional conventional long stems. Short stems are designed to facilitate minimal-invasive surgery, improve bone-stock preservation, and mimic a physiological load distribution. However, there is little evidence of the long-term outcome of short stems. This study aims to analyze the ten year survival rates and clinical outcome of one specific metaphyseal short hip stem implant. METHODS: We retrospectively analyzed the patient records of the patients who underwent a total hip arthroplasty with a monoblock partial collum sparing metaphyseal short hip stem prosthesis in 2008 and 2009 in our clinic. Patients were contacted, and clinical follow-up was recorded using the German version of the modified Harris Hip Score. Furthermore, complications, revision surgery, and post-operative radiographs were analyzed. RESULTS: Data from 339 primary implantations in 322 patients were retrieved. The mean follow-up was 10.6 years. Seven patients underwent a revision. The ten year survival rate with any revision surgery as the endpoint was 97.5%. The mean modified Harris Hip Score was 86 points (range 30 to 91 points). Five patients had an intraoperative fracture of the femur (1.6%). Two patients (0.6%) had a dislocation of the hip. The stem tip-to-cortex distance, measured in the anterior posterior view, was 2.6 mm (range 0 to 8.3 mm). CONCLUSION: The ten year survival rate of our used monoblock partial collum sparing metaphyseal short hip stem implant is comparable to traditional stems for total hip arthroplasty.

Non-invasive assessment of muscle compartment elasticity by pressure-related ultrasound in pediatric trauma: a prospective clinical study in 25 cases of forearm shaft fractures.

BACKGROUND: Soft-tissue swelling after limb fractures in pediatric patients is well known to be a risk factor for developing acute compartment syndrome (ACS). Clinical assessment alone is uncertain in specific cases. Recently, we proposed a non-invasive ultrasound-based method to objectify muscle compartment elasticity for monitoring. We hypothesize a strong correlation between the soft-tissue swelling after stabilization of upper limb fractures and the compartment elasticity objectified with a novel ultrasound-based approach in pediatric trauma. PATIENTS AND METHODS: In a prospective clinical study, children suffering forearm fractures but not developing an ACS were included. The muscle compartment elasticity of the m. flexor carpi ulnaris was assessed after surgical intervention by a non-invasive, ultrasound-based method resulting in a relative elasticity (RE in %) in both the control (healthy limb) and study group (fractured limb). Soft-tissue swelling was categorized in four different levels (0-3) and correlated with the resulting RE (%). RESULTS: The RE in the study group (15.67%, SD ± 3.06) showed a significantly decreased level (p < 0.001) compared with the control (22.77%, SD ± 5.4). The categorized grade of soft-tissue swelling resulted in a moderate correlation with the RE (rs = 0.474). CONCLUSIONS: The presented study appears to represent a novel approach to assess the posttraumatic pressure changes in a muscle compartment after fracture stabilization non-invasively. In this first clinical study in pediatric cases, our measurement method represents a low-cost, easy, and secure approach that has the potential to substitute invasive measurement of suspected ACS in muscle compartment conditions. Further investigations in lager cohorts are required to prove its daily clinical practicability and to confirm the expected reliability.

The timing of tether breakage influences clinical results after VBT.

INTRODUCTION: Tether breakage is a frequent mechanical complications after vertebral body tethering (VBT), but not all patients with a breakage show loss of correction. The reason of this clinical finding has not yet been clarified. We hypothesized that the integrity of the tether is relevant only in the early stages after VBT, when it drives growth modulation and tissue remodelling. After these mechanisms have taken place, the tether loses its function and a breakage will not alter the new shape of the spine. Thus, tether breakage would have a greater clinical relevance when occurring shortly after surgery. METHODS: All consecutive patients who underwent VBT and had a min. 2-year follow-up were included. The difference in curve magnitude between the 1st standing x-ray and the last follow-up was calculated (ΔCobb). For each curve, the presence and timing of tether breakage were recorded. The curves were grouped according to if and when the breakage was observed (no breakage, breakage at 0-6 months, 6-12 months, > 12 months). The ΔCobb was compared among these groups with the analysis of variance (ANOVA). RESULTS: Data from 152 curves were available: 68 with no breakage, 12 with a breakage at 0-6 months, 37 at 6-12 months and 35 > 12 months. The ANOVA found significant difference in the ΔCobb among the groups (Sum of square 2553.59; degree of freedom 3; mean of square 851.1; Fisher test 13.8; P < 0.0001). Patients with no breakage or breakage at > 12 months had similar ΔCobb (mean 4.8° and 7.8°, respectively, P = 0.3), smaller than the 0-6 or 6-12 groups (15.8° and 13.8°, respectively). CONCLUSION: Tether breakage leads to a consistent loss of correction when occurring within the first 12 months, while it has limited clinical relevance when occurring later on.

[Treatment strategies for pathological fractures of the spine]. / Versorgungsstrategien bei pathologischen Frakturen der Wirbelsäule.

BACKGROUND: Pathological fractures and instabilities of the spine are most often caused by primary tumors that hematogenously metastasize into the spine. In this context breast, prostate, kidney cell and bronchial carcinomas are the most relevant causative diseases. Furthermore, multiple myeloma is another frequent entity. Primary tumors of the spine are correspondingly rare and only make up a small proportion of all malignant processes in the spine. DECISION MAKING: The main symptom of pain is prognostically unfavorable in this context and is often associated with progressive instability or pathological fractures. To objectify the treatment approach the neurological status, an oncological assessment, the biomechanical stability and (systemic) general condition (NOMS criteria) of the patient have to be considered. Another major factor is the radiation sensitivity of the tumor. The spinal instability neoplastic (SIN) score is recommended to assess stability. Regardless of whether conservative or surgical treatment is carried out, interdisciplinary cooperation between the specialist departments must be guaranteed in order to achieve adequate treatment for the patient. TREATMENT: If a curative approach is followed an individualized and interdisciplinary surgical strategy must be performed to achieve an R0 resection, usually as a spondylectomy. In the case of palliative treatment, the goal of surgical treatment must be pain reduction, stability and avoidance or restoration of neurological deficits. This requires stabilization in a percutaneous or open technique, possibly in combination with decompression and local tumor debulking.

Non-invasive and reliable assessment of compartment elasticity by pressure related ultrasound: An in-vitro study.

PURPOSE: The development of acute compartment syndrome is a serious threat to trauma patients. The clinical assessment alone is not reliable enough to determine the need for fasciotomy in many cases. The Physician´s assessment of the elasticity of the muscle compartment might be particularly important to objectively evaluate the pressure in this enclosed space. The purpose of this study was to determine the observer´s reproducibility, of compartment elasticity measurements by a novel ultrasonic approach. METHODS: Increasing intra-compartmental pressures (ICP) were simulated in a water filled in-vitro model. Pressure related ultrasound was used to determine the relative elasticity (RE) of soft tissue compartments. A pressure transducing probe head was combined with the ultrasonic probe to obtain cross section views of the simulated compartment and to detect the amount of applied pressure by the observer. In this model, the compartment depth without compression (P0) was set to be 100%. Changes of the compartment depth due to a probe pressure of 80 mmHg (P80) were correlated to P0 and an elasticity quotient as a value for RE (%) was calculated. Twelve blinded observers performed measurements for RE determination (%) under three pressure conditions. Reproducibility was calculated using intraclass correlation coefficient (ICC). RESULTS: Measurements (n = 432) revealed that the RE (%) in the control group was 17,06% (SD+/-2,13), whereas the RE of the group ICP30 significantly decreased to 12,66% (SD+/- 1,19) (p<0,001). The ICP50 group revealed a further significant decrease to 8,43% (SD+/- 0,67) (p<0,001). Repeated measurement of RE and ICP showed a high level of correlation (spearman correlation coefficient: roh=0,922). A RE <14% resulted in a sensitivity of 96% and a specificity of 90,3% for diagnosis of an ICP >30 mmHg. ICCinter was 0,986; 95%, CI: 0,977-0,992 (p<0,001). DISCUSSION: The presented ultrasound-based approach reliably assesses the elasticity in a simulated compartment model. In this pioneer study investigating the inter- and intra-observer reproducibility, this method of measurement appears to be of low cost in addition to being an easy and secure approach that may have the potential to substitute invasive measurement. Further investigations are required to improve its feasibility and to confirm the reliability under clinical conditions.

[Medical ID and emergency apps: A useful tool in emergency situations or a waste of time?] / Notfall-Apps: vergeudete Zeit oder sinnvolles Instrument in der präklinischen Versorgung von Traumapatienten?

BACKGROUND: In order to provide safe care to a patient in an emergency situation, it is useful to know something about the patient's previous medical conditions and medication. For this very reason smartphones have been equipped with so-called emergency apps (e.g. medical-ID, emergency-ID). The aim of our study was to find out whether the owners of smartphones are using the apps and whether medical professionals are trying to access this information. METHODS: We conducted a survey among patients in our outpatient clinic at a level one trauma center. We collected data over 3 months regarding the usage behavior of the aforementioned apps. We simultaneously asked emergency physicians at various hospitals about their experiences with these apps. RESULTS: We were able to interview 192 patients and 103 emergency physicians. The emergency apps were unknown to 45% (n = 79) of the respondents; only 10% (n = 19) of the respondents had the app with data stored. Furthermore, it was found that a total of 21% (n = 41) of the persons carried a note on themselves with previous illnesses and medication. Of the surveyed physicians, 42% (n = 44) stated that they had heard of the app before; however, only 6% (n = 5) routinely searched the smartphone for relevant information in the case of nonresponsive patients. Only 14% of physicians (n = 14) have successfully used the app so far. CONCLUSION: The collected data show that the emergency apps are still unknown to many patients and emergency physicians alike. Due to the low distribution it does not seem to be recommendable to search the smartphone for the apps in time-critical situations after accidents. For patients over 55 years of age, it currently seems more promising to search their wallets for information regarding their previous illnesses.

Non-invasive measurement of muscle compartment elasticity in lower limbs to determine acute compartment syndrome: Clinical results with pressure related ultrasound.

PURPOSE: Close monitoring of patients at risk to develop an acute compartment syndrome (ACS) is well known to be essential. There is a relevant risk that clinical assessment alone is not reliable enough. Reliable assessment of the elasticity of the muscle compartment might represent a helpful tool to assess the pressure in this enclosed space. Therefore, the purpose of this study was to determine the feasibility of muscle elasticity measurements by a non-invasive device. METHODS: In a prospective study, patients with elevated intra-compartmental pressure (ICP) were included. An ultrasound-based measurement approach was used to determine the relative elasticity (RE) of both, the affected and unaffected limb. A pressure transducing ultrasonic probe head was combined with the probe to obtain cross section views of the anterior tibial compartment and to detect the observer´s amount of pressure applied on the limb surface. The compartment depth without compression (P0) corresponds to 100%. The difference to the compartment depth with a probe pressure of 80mmHg (P80) on the limb (delta) related to P0 resulted in a value of relative elasticity (%). These values were compared with the invasive needle measurement (mmHg) regarding their intra-individual difference and correlation of the compartmental pressure. RESULTS: In six trauma patients the relative elasticity in their paired limbs showed a significant difference. The RE in the healthy compartments revealed a level of 17.95% (SD+/-5,4), whereas the RE of the affected limbs significantly decreased to a mean of 5,14% (SD+/-2,1) (p < 0,0001). The average values of the repetitively measured RE and the ICP showed a high level of correlation (spearman correlation coefficient: roh = 0,929). The RE less than 10,5% of the anterior tibial compartment had a sensitivity of 95,8% and a specificity of 87,5% to an appropriate diagnosis of ACS. DISCUSSION: The presented study appears to represent a promising approach to reliably assess the pressure in a muscle compartment. In this first clinical study, our measurement method represents a low cost, easy and secure approach that has the potential to substitute invasive measurement. Further investigations and development in lager cohorts are required to improve its practicality and to confirm the reliability.

Plasmid DNA contaminant in molecular reagents.

Background noise in metagenomic studies is often of high importance and its removal requires extensive post-analytic, bioinformatics filtering. This is relevant as significant signals may be lost due to a low signal-to-noise ratio. The presence of plasmid residues, that are frequently present in reagents as contaminants, has not been investigated so far, but may pose a substantial bias. Here we show that plasmid sequences from different sources are omnipresent in molecular biology reagents. Using a metagenomic approach, we identified the presence of the (pol) of equine infectious anemia virus in human samples and traced it back to the expression plasmid used for generation of a commercial reverse transcriptase. We found fragments of multiple other expression plasmids in human samples as well as commercial polymerase preparations. Plasmid contamination sources included production chain of molecular biology reagents as well as contamination of reagents from environment or human handling of samples and reagents. Retrospective analyses of published metagenomic studies revealed an inaccurate signal-to-noise differentiation. Hence, the plasmid sequences that seem to be omnipresent in molecular biology reagents may misguide conclusions derived from genomic/metagenomics datasets and thus also clinical interpretations. Critical appraisal of metagenomic data sets for the possibility of plasmid background noise is required to identify reliable and significant signals.

[The gut microbiome in Parkinson's disease]. / Das Darmmikrobiom bei der Parkinson-Krankheit.

The vast majority of Parkinson's disease (PD) cases are of sporadic origin and despite extensive research in recent years, the etiology still remains unclear. Several current case control studies are aiming to characterize a putative PD-specific composition of the gut microbiome, reflecting the potential relevance of microbiota in the pathogenesis of PD. Although methodologies and cohort sizes differed, the currently available studies showed reproducible or consistent results in terms of PD-specific alterations to the intestinal bacteria. By applying metagenomic sequencing procedures, it is even possible to distinguish PD cases from healthy individuals at a very early disease stage by means of individually modified microbiota. Among others, microbiota that are associated with an altered intestinal barrier or immune function, such as Akkermansia, Lactobacillus, Faecalibacterium and Prevotella were significantly over-represented or under-represented. There may even be a prodromal microbiome, as a comparable microbial shift is also found in patients with rapid eye movement (REM) sleep behavior disorder (RBD), a risk factor for the later development of synucleinopathies, such as PD.

The gut microbiome is associated with behavioural task in honey bees.

The gut microbiome is recognised as playing an integral role in the health and ecology of a wide variety of animal taxa. However, the relationship between social behavioural traits and the microbial community has received little attention. Honey bees are highly social and the workers perform different behavioural tasks in the colony that cause them to be exposed to different local environments. Here we examined whether the gut microbial community composition of worker honey bees is associated with the behavioural tasks they perform, and therefore also the local environment they are exposed to. We set up five observation hives, in which all workers were matched in age and observed the behaviour of marked bees in each colony over 4 days. The gut bacterial communities of bees seen performing predominantly foraging or predominantly in nest tasks were then characterised and compared based on amplicon sequencing of the 16S rRNA gene. Our results show that some core members of the unique honey bee gut bacterial community are represented in different relative abundances in bees performing different behavioural tasks. The differentially represented bacterial taxa include some thought to be important in carbohydrate metabolism and transport, and also linked to bee health. The results suggest an influence of task-related local environment exposure and diet on the honey bee gut microbial community and identify focal core taxa for further functional analyses.

Hypothermia does not influence liver damage and function in a porcine polytrauma model.

BACKGROUND: Previous studies revealed evidence that induced hypothermia attenuates ischemic organ injuries after severe trauma. In the present study, the effect of hypothermia on liver damage was investigated in a porcine long term model of multi-system injury, consisting of blunt chest trauma, penetrating abdominal trauma, musculoskeletal injury, and hemorrhagic shockMETHODS: In 30 pigs, a standardized polytrauma including blunt chest trauma, penetrating abdominal trauma, musculoskeletal injury, and hemorrhagic shock of 45% of total blood volume was induced. Following trauma, hypothermia of 33∘C was induced for 12 h and intensive care treatment was evaluated for 48 h. As outcome parameters, we assessed liver function and serum transaminase levels as well as a histopathological analysis of tissue samples. A further 10 animals served as controls. RESULTS: Serum transaminase levels were increased at the end of the observation period following hypothermia without reaching statistical significance compared to normothermic groups. Liver function was preserved (p⩽ 0.05) after the rewarming period in hypothermic animals but showed no difference at the end of the observation period. In H&E staining, cell death was slightly increased hypothermic animals and caspase-3 staining displayed tendency towards more apoptosis in hypothermic group as well. CONCLUSIONS: Induction of hypothermia could not significantly improve hepatic damage during the first 48 h following major trauma. Further studies focusing on multi-organ failure including a longer observation period are required to illuminate the impact of hypothermia on hepatic function in multiple trauma patients.

Impact of pelvic fractures on the early clinical outcomes of severely injured trauma patients.

BACKGROUND: Pelvic fractures contribute to morbidity and mortality following injury. We sought to study the impact of pelvic fractures on the clinical course and outcomes of trauma patients with a pelvic fracture in comparison to patients with similar injury severity without pelvic fracture to identify potential parameters to track patients' clinical course post-injury. METHODS: A cohort of 206 consecutive blunt trauma survivors, studied over a 5-year period in a level I trauma center of which 75 patients (36.4%) had a pelvic fracture, was included in the study. To perform a retrospective cohort study with matched controls, 60 patients of the pelvic fracture group [(PF), 41 males and 19 females; age: 40 ± 17; injury severity score (ISS): 26.6 ± 9.3] were compared to 60 patients without pelvic fracture (non-PF) trauma as controls (41 males and 19 females; age: 40 ± 13; ISS: 26.9 ± 7.7), both with matching age (±5 years), sex, and ISS (±5 points). RESULTS: Statistically significant differences were observed in Intensive Care Unit (ICU) length of stay (LOS), total LOS, and Marshall MOD score between PF and non-PF groups, respectively. Acid-base markers such as pH, lactate, LDH, and base deficit were all significantly altered in PF compared to non-PF cohort upon admission. Moreover, our analysis showed significant differences in inflammatory biomarkers (Prolactin, CRP, and IL-6), and clinical parameters (CPK, Hgb, Platelets count, and WBC) over the 7-day clinical course in patients with PF when compared to non-PF cohort. CONCLUSION: In this matched cohort, patients with pelvic fractures exhibited biochemical and physiological alterations upon admission. Furthermore, our results suggest that pelvic fracture affects the clinical outcomes in severely injured patients, independently of injury severity, mechanism of injury, age or gender.

Cardiac Depression in Pigs after Multiple Trauma - Characterization of Posttraumatic Structural and Functional Alterations.

The purpose of this study was to define the relationship between cardiac depression and morphological and immunological alterations in cardiac tissue after multiple trauma. However, the mechanistic basis of depressed cardiac function after trauma is still elusive. In a porcine polytrauma model including blunt chest trauma, liver laceration, femur fracture and haemorrhage serial trans-thoracic echocardiography was performed and correlated with cellular cardiac injury as well as with the occurrence of extracellular histones in serum. Postmortem analysis of heart tissue was performed 72 h after trauma. Ejection fraction and shortening fraction of the left ventricle were significantly impaired between 4 and 27 h after trauma. H-FABP, troponin I and extracellular histones were elevated early after trauma and returned to baseline after 24 and 48 h, respectively. Furthermore, increased nitrotyrosine and Il-1ß generation and apoptosis were identified in cardiac tissue after trauma. Main structural findings revealed alteration of connexin 43 (Cx43) and co-translocation of Cx43 and zonula occludens 1 to the cytosol, reduction of α-actinin and increase of desmin in cardiomyocytes after trauma. The cellular and subcellular events demonstrated in this report may for the first time explain molecular mechanisms associated with cardiac dysfunction after multiple trauma.

Functional implications of microbial and viral gut metagenome changes in early stage L-DOPA-naïve Parkinson's disease patients.

BACKGROUND: Parkinson's disease (PD) presently is conceptualized as a protein aggregation disease in which pathology involves both the enteric and the central nervous system, possibly spreading from one to another via the vagus nerves. As gastrointestinal dysfunction often precedes or parallels motor symptoms, the enteric system with its vast diversity of microorganisms may be involved in PD pathogenesis. Alterations in the enteric microbial taxonomic level of L-DOPA-naïve PD patients might also serve as a biomarker. METHODS: We performed metagenomic shotgun analyses and compared the fecal microbiomes of 31 early stage, L-DOPA-naïve PD patients to 28 age-matched controls. RESULTS: We found increased Verrucomicrobiaceae (Akkermansia muciniphila) and unclassified Firmicutes, whereas Prevotellaceae (Prevotella copri) and Erysipelotrichaceae (Eubacterium biforme) were markedly lowered in PD samples. The observed differences could reliably separate PD from control with a ROC-AUC of 0.84. Functional analyses of the metagenomes revealed differences in microbiota metabolism in PD involving the ẞ-glucuronate and tryptophan metabolism. While the abundances of prophages and plasmids did not differ between PD and controls, total virus abundance was decreased in PD participants. Based on our analyses, the intake of either a MAO inhibitor, amantadine, or a dopamine agonist (which in summary relates to 90% of PD patients) had no overall influence on taxa abundance or microbial functions. CONCLUSIONS: Our data revealed differences of colonic microbiota and of microbiota metabolism between PD patients and controls at an unprecedented detail not achievable through 16S sequencing. The findings point to a yet unappreciated aspect of PD, possibly involving the intestinal barrier function and immune function in PD patients. The influence of the parkinsonian medication should be further investigated in the future in larger cohorts.

[The rotationally stable screw-anchor with trochanteric stabilizing plate (RoSA/TSP) : First results in unstable trochanteric femur fractures]. / Der Rotationsstabile Schraubanker mit winkelstabiler Stützplatte (RoSA/TAP) : Erste klinische Evaluation bei instabilen trochantären Frakturen.

BACKGROUND: In unstable trochanteric fractures, the extramedullary rotationally stable screw-anchor (RoSA) combines the benefits of the load and rotational stability of the blade with the advantages of the screw (pull-out resistance, compression capability) in a single load carrier, and was designed to prevent femoral neck shortening by using an additional locked trochanteric stabilizing plate (TSP). OBJECTIVES: The aim of the current prospective cohort study was the clinical evaluation of the RoSA/TSP system regarding the mechanical re-operation rate and the amount of postoperative femoral neck shortening. METHODS: From September 2011 to January 2014 80 patients with unstable trochanteric fractures underwent internal extramedullary fixation with the RoSA/TSP (Königsee Implantate GmbH, Allendorf, Germany). Due to fracture stability and after induction of compression, additional long locked antitelescoping screws (AT, n = 1-4) were placed reaching the femoral head. Radiological (femoral neck shortening) and clinical re-examination of patients (n = 61) was performed 6-10 weeks and 6-10 months later. RESULTS: In the 61 re-examined patients (76 %) femoral neck shortening was very low with 2 mm 6-10 months after operation. Re-operations occurred in 8 % (n = 6) and in 4 % (n = 3) as prophylactic surgical intervention. Whereas one-third (4 %) of re-operations occurred due to iatrogenic surgical problems from the first operation two-thirds of patients (8 %) had a re-operation due to delay of bone union (3× nonunion, 3 planned removals of AT-screws to improve healing). The in-hospital mortality was 3 % (n = 2). CONCLUSIONS: The fixation of unstable trochanteric femur fractures using the RoSA/TSP in a first clinical setting led to a great primary stability, with significant advantages with regard to limited femoral neck shortening. However, the rigidity of the construct with its consequences regarding bone healing can be challenging for the surgeon. Nevertheless, in some cases of revision it could be beneficial for stability.

Sera from severe trauma patients with pneumonia and without infectious complications have differential effects on neutrophil biology.

BACKGROUND: Major trauma patients (TP) developing imbalanced immune response are at high risk for infectious post-injury complications including pneumonia. Neutrophils play a central role in the host defense against bacteria and thereby pathogenesis of infections. While there are numerous studies about neutrophil function after trauma, data about their biology in patients who suffer from pneumonia following trauma are sparse. Here, we studied the effect of serum isolated from patients who do and do not develop infection (inf.) on the biology of neutrophils from healthy volunteers. METHODS: Sera samples from eighteen TP with an injury severity score above 16 were obtained. Nine patients were grouped to no inf. group (TP without pneumonia), and nine to inf. group (TP with pneumonia). Samples were obtained at admission to emergency department (ED), a day prior pneumonia diagnosis (1 d prior inf) or at the day of diagnosis (1 d prior inf). Samples from the equal post-injury days in the corresponding no inf. group were used. Neutrophils from nine healthy volunteers were isolated. Effects for sera isolated from infected and non-infected patients on neutrophil biology were analyzed. Migratory capacity of neutrophils towards TP's serum, their CD11b and CD62L membrane receptor expression and oxidative burst activity after stimulation with TP's serum were determined and compared between groups. RESULTS: Migratory capacity of neutrophils was significantly increased after trauma and persisted during the study period. CD11b expression in all groups was significantly increased. CD62L expression decreased generally in samples from ED and recovered later to baseline. Stratifying no inf. and inf. groups showed significantly decreased migratory capacity, increased CD11b and significantly decreased CD62L expression in the no inf. group. These differences persisted during the complete observational period. ROS production was strongly reduced in the no inf. group compared to the inf. group at later experimental time points. CONCLUSIONS: This data indicate that patients at risk for pneumonia development have differentially and early activated neutrophils following trauma compared to patients who are not at risk for post-injury complication. Studies about the differential biology of neutrophils and their immediately after trauma modified activity depending on the post-injury clinical course are warranted, and may deliver predictive or even therapeutic strategies to control inflammation.

Characterization of blunt chest trauma in a long-term porcine model of severe multiple trauma.

Chest trauma has a significant relevance on outcome after severe trauma. Clinically, impaired lung function typically occurs within 72 hours after trauma. However, the underlying pathophysiological mechanisms are still not fully elucidated. Therefore, we aimed to establish an experimental long-term model to investigate physiological, morphologic and inflammatory changes, after severe trauma. Male pigs (sus scrofa) sustained severe trauma (including unilateral chest trauma, femur fracture, liver laceration and hemorrhagic shock). Additionally, non-injured animals served as sham controls. Chest trauma resulted in severe lung damage on both CT and histological analyses. Furthermore, severe inflammation with a systemic increase of IL-6 (p = 0.0305) and a local increase of IL-8 in BAL (p = 0.0009) was observed. The pO2/FiO2 ratio in trauma animals decreased over the observation period (p < 0.0001) but not in the sham group (p = 0.2967). Electrical Impedance Tomography (EIT) revealed differences between the traumatized and healthy lung (p < 0.0001). In conclusion, a clinically relevant, long-term model of blunt chest trauma with concomitant injuries has been developed. This reproducible model allows to examine local and systemic consequences of trauma and is valid for investigation of potential diagnostic or therapeutic options. In this context, EIT might represent a radiation-free method for bedside diagnostics.