Time trajectories and within-subject correlations of matrix metalloproteinases 3, 8, 9, 10, 12, and 13 serum levels and their ability to predict mortality in polytraumatized patients: a pilot study.

BACKGROUND: Managing polytrauma victims poses a significant challenge to clinicians since applying the same therapy to patients with similar injury patterns may result in different outcomes. Using serum biomarkers hopefully allows for treating each multiple injured in the best possible individual way. Since matrix metalloproteinases (MMPs) play pivotal roles in various physiological processes, they might be a reliable tool in polytrauma care. METHODS: We evaluated 24 blunt polytrauma survivors and 12 fatalities (mean age, 44.2 years, mean ISS, 45) who were directly admitted to our Level I trauma center and stayed at the intensive care unit for at least one night. We determined their MMP3, MMP8, MMP9, MMP10, MMP12, and MMP13 serum levels at admission (day 0) and on days 1, 3, 5, 7, and 10. RESULTS: Median MMP8, MMP9, and MMP12 levels immediately rose after the polytrauma occurred; however, they significantly decreased from admission to day 1 and significantly increased from day 1 to day 10, showing similar time trajectories and (very) strong correlations between each two of the three enzyme levels assessed at the same measurement point. For a two-day lag, autocorrelations were significant for MMP8 (- 0.512) and MMP9 (- 0.302) and for cross-correlations between MMP8 and MMP9 (- 0.439), MMP8 and MMP12 (- 0.416), and MMP9 and MMP12 (- 0.307). Moreover, median MMP3, MMP10, and MMP13 levels significantly increased from admission to day 3 and significantly decreased from day 3 to day 10, showing similar time trajectories and an (almost) strong association between every 2 levels until day 7. Significant cross-correlations were detected between MMP3 and MMP10 (0.414) and MMP13 and MMP10 (0.362). Finally, the MMP10 day 0 level was identified as a predictor for in-hospital mortality. Any increase of the MMP10 level by 200 pg/mL decreased the odds of dying by 28.5%. CONCLUSIONS: The time trajectories of the highly varying individual MMP levels elucidate the involvement of these enzymes in the endogenous defense response following polytrauma. Similar time courses of MMP levels might indicate similar injury causes, whereas lead-lag effects reveal causative relations between several enzyme pairs. Finally, MMP10 abundantly released into circulation after polytrauma might have a protective effect against dying.

Serum levels of matrix metalloproteinases 1, 2, and 7, and their tissue inhibitors 1, 2, 3, and 4 in polytraumatized patients: Time trajectories, correlations, and their ability to predict mortality.

There has been limited research on assessing metalloproteinases (MMPs) 1, 2, and 7, as well as their tissue inhibitors (TIMPs) 1, 2, 3, and 4 in the context of polytrauma. These proteins play crucial roles in various physiological and pathological processes and could be a reliable tool in polytrauma care. We aimed to determine their clinical relevance. We assessed 24 blunt polytrauma survivors and 12 fatalities (mean age, 44.2 years, mean ISS, 45) who were directly admitted to our Level I trauma center and spent at least one night in the intensive care unit. We measured serum levels of the selected proteins on admission (day 0) and days 1, 3, 5, 7, and 10. The serum levels of the seven proteins varied considerably among individuals, resulting in similar median trend curves for TIMP1 and TIMP4 and for MMP1, MMP2, TIMP2, and TIMP3. We also found a significant interrelationship between the MMP2, TIMP2, and TIMP3 levels at the same measurement points. Furthermore, we calculated significant cross-correlations between MMP7 and MMP1, TIMP1 and MMP7, TIMP3 and MMP1, TIMP3 and MMP2, and TIMP4 and TIMP3 and an almost significant correlation between MMP7 and TIMP1 for a two-day-lag. The autocorrelation coefficient reached statistical significance for MMP1 and TIMP3. Finally, lower TIMP1 serum levels were associated with in-hospital mortality upon admission. The causal effects and interrelationships between selected proteins might provide new insights into the interactions of MMPs and TIMPs. Identifying the underlying causes might help develop personalized therapies for patients with multiple injuries. Administering recombinant TIMP1 or increasing endogenous production could improve outcomes for those with multiple injuries. However, before justifying further investigations into basic research and clinical relevance, our findings must be validated in a multicenter study using independent cohorts to account for clinical and biological variability.

Serum Angiopoietin-2 level increase differs between polytraumatized patients with and without central nervous system injuries.

Since endothelial cells rapidly release Angiopoietin-2 (Ang-2) in response to vascular injury and inflammatory stimuli, we aimed to investigate if its serum levels increase in polytraumatized patients. Our cohort study evaluated 28 blunt polytrauma survivors (mean age, 38.4 years; median ISS, 34) who were directly admitted to our level I trauma center in 2018. We assessed the serum Ang-2 level at admission and on days 1, 3, 5, 7, and 10 during hospitalization. Ang-2 was released into the circulation immediately after polytrauma. At admission (day 0), it amounted to 8286 ± 5068 pg/mL, three-and-a-half times the reference value of 2337 ± 650 pg/mL assessed in a healthy control group. Subgroup analysis provided a higher mean Ang-2 level in the CNSI group combining all patients suffering a brain or spinal cord injury compared to the non-CNSI group solely on day 0 [11083 ± 5408 pg/mL versus 3963 ± 2062 pg/mL; p < 0.001]. Whereas the mean Ang-2 level increased only in the non-CNSI group from day 0 to day 3 (p = 0.009), the respective curves showed similar continuous decreases starting with day 3. Multivariate logistic regression analysis revealed an association between the Ang-2 day 0 level and the presence of a CNSI (OR = 1.885; p = 0.048). ROC analysis provided a cutoff level of 5352 pg/mL. In our study group, serum Ang-2 levels assessed at admission differed between polytraumatized patients with and without brain or spinal cord injuries. Based on our findings, we consider serum Ang-2 levels an effective biomarker candidate for indicating CNSI in these patients at admission, worthy of further evaluation in large multicenter studies.

Patellar Size Variation at the Quadriceps Tendon-Bone Block Harvest Site: A Magnetic Resonance Imaging Study to Evaluate the Safe Zone for Harvesting a Sufficient Bone Block.

BACKGROUND: Quadriceps tendon (QT) autografts with and without a bone block are the least studied and least used options for anterior cruciate ligament reconstruction surgery. In particular, there is a lack of literature describing patellar anatomy. Until now, guidelines for patellar bone block harvesting have been based solely on personal experience. In this study, we intended to derive recommendations from physical regularities and objective criteria. PURPOSE: To determine the maximal, individual-related length and depth of the bone block that can be safely harvested and to provide guidelines to help surgeons make decisions on graft choice. STUDY DESIGN: Descriptive laboratory study. METHODS: The study group consisted of 50 male participants and 50 female participants (mean age, 29.4 ± 7.9 years) who underwent 3.0-T magnetic resonance imaging of their knee. Patellar height was determined at the center of the middle third of the QT insertion on the patella and the medial and lateral endpoints; the depth was measured at the midpoints of the respective heights. RESULTS: The mean width of the QT and the mean thickness were 49.0 ± 7.6 and 7.3 ± 1.0 mm, respectively. The mean patellar thickness in reference to the medial endpoint, the center, and the lateral endpoint was 18.3 ± 2.4, 17.9 ± 2.3, and 15.1 ± 2.3 mm, respectively, whereas the mean patellar height was 35.1 ± 4.1, 36.7 ± 4.2, and 35.1 ± 3.9 mm. In general, the tendon and patellar dimensions were significantly larger in male participants than in female participants (P = .016). CONCLUSION: Bone block harvesting, with its depth not exceeding 50% of the patellar thickness and its length accounting for <50% of the patellar height, poses the least risk for a patellar fracture when located medial to midline. If the bone block is excised from the medial half of the central area (the latter is defined by the middle third of the QT insertion), with the outer edge of the saw positioned at the medial border of the central area, a graft of 15 mm length, 10 mm width, and 8 mm depth can be safely harvested in all White male participants and almost all female participants taller than 165 cm, according to our findings. CLINICAL RELEVANCE: This is the first study presenting recommendations for patellar bone block harvesting at the quadriceps tendon insertionbased on physical regularities and objective criteria and not on personal experience.

Impact of COVID-19 lockdown on suicide attempts : A retrospective analysis of the springtime admissions to the trauma resuscitation room at the Medical University of Vienna from 2015-2020.

BACKGROUND: In response to the current coronavirus disease 2019 (COVID-19) pandemic the Austrian government issued a lockdown from 16 March to 15 May 2020. As periods of economic and emotional burden have proven to detrimentally affect people's psychological health, healthcare officials warned that the strict measures could have a serious impact on psychological health, leading to an increase in suicide attempts. Thus, the objective was to provide evidence for this assumption. METHODS: All adult patients admitted to the trauma resuscitation room of the Medical University of Vienna during the lockdown period following a suicide attempt were included in this analysis, forming the study group. Suicidal patients treated during the same period in 2015, 2016, 2018, and 2019 were pooled to create the control group. The year 2017 was excluded because another major hospital in Vienna was partially closed due to a change in infrastructure, resulting in an increased number of severely injured patients treated at our department. As the lockdown caused a markedly decreased number of patients admitted due to other reasons than suicide the actual number was replaced with the average number of patients admitted in the relevant previous 4 years. RESULTS: By comparing the study and the control group based on this realistic estimate we revealed an increase in attempted suicides during the lockdown period (p = 0.001). Demographic, mental health-related, and injury specific patient data did not differ between the groups. CONCLUSION: The results strongly urge for an improvement in crisis intervention and suicide prevention measures in the event of a future lockdown.

Impact of Polytrauma and Acute Respiratory Distress Syndrome on Markers of Fibrinolysis: A Prospective Pilot Study.

Acute respiratory distress syndrome (ARDS), which is associated with major morbidity and high mortality, is commonly developed by polytraumatized patients. Its pathogenesis is complex, and its development is difficult to anticipate, as candidate biomarkers for the prediction of ARDS were found not to be reliable for clinical use. In this prospective study, we assessed the serum antigen levels of tissue plasminogen activator (tPA) and plasminogen activator inhibitor type-1 (PAI-1) of 28 survivors of blunt polytrauma (age ≥18 years; injury severity score ≥16) at admission and on days 1, 3, 5, 7, 10, 14, and 21 of hospitalization. Our results show that these patients presented high mean tPA and PAI-1 antigen levels at admission; despite their decline, these parameters remained elevated for 3 weeks. Over this period, the mean tPA antigen level was higher in polytrauma victims suffering from ARDS than in those without ARDS, whereas the mean PAI-1 level was higher in polytrauma victims sustaining pneumonia than in those without pneumonia. Moreover, in each individual developing ARDS, the polytrauma-related elevated tPA antigen level either continued to rise after admission or suffered a second increase up to the onset of ARDS, declining immediately thereafter. Therefore, our findings support the assessment of serum tPA antigen levels after the initial treatment of polytraumatized patients, as this parameter shows potential as a biomarker for the development of ARDS and for the consequent identification of high-risk individuals.

Systemic release of heat-shock protein 27 and 70 following severe trauma.

Trauma represents a major cause of morbidity and mortality worldwide. The endogenous inflammatory response to trauma remains not fully elucidated. Pro-inflammation in the early phase is followed by immunosuppression leading to infections, multi-organ failure and mortality. Heat-shock proteins (HSPs) act as intracellular chaperons but exert also extracellular functions. However, their role in acute trauma remains unknown. The aim of this study was to evaluate serum concentrations of HSP 27 and HSP 70 in severely injured patients. We included severely injured patients with an injury severity score of at least 16 and measured serum concentration of both markers at admission and on day two. We found significantly increased serum concentrations of both HSP 27 and HSP 70 in severely injured patients. Concomitant thoracic trauma lead to a further increase of both HSPs. Also, elevated concentrations of HSP 27 and HSP 70 were associated with poor outcome in these patients. Standard laboratory parameters did not correlate with neither HSP 27, nor with HSP 70. Our findings demonstrate involvement of systemic release of HSP 27 and HSP 70 after severe trauma and their potential as biomarker in polytraumatized patients.

IL-33 and its increased serum levels as an alarmin for imminent pulmonary complications in polytraumatized patients.

Background: According to recently published findings, we hypothesized that serum interleukin-33 (IL-33) may qualify for predicting pulmonary complications in polytraumatized patients. Methods: One hundred and thirty patients (age ≥ 18 years, ISS ≥ 16) were included in our prospective analysis after primary admission to our level I trauma center during the first post-traumatic hour. Serum samples immediately after admission and on day 2 after trauma were obtained and analyzed. Results: Median initial IL-33 levels (in picograms per milliliter) were higher in polytrauma victims (1) with concomitant thoracic trauma [5.08 vs. 3.52; p = 0.036], (2) sustaining parenchymal lung injury (PLI) [5.37 vs. 3.71; p = 0.027], and (3) developing acute respiratory distress syndrome (ARDS) [6.19 vs. 4.48; p = 0.003], compared to the respective rest of the study group. The median initial IL-33 levels were higher in patients experiencing both PLI and ARDS compared to those sustaining PLI and not developing ARDS [6.99 vs. 4.69; p = 0.029]. ROC statistics provided an AUC of 0.666 (p = 0.003) and a cut-off value of 4.77 (sensitivity, 71.8%; specificity, 75.7%) for predicting ARDS. Moreover, a higher initial median IL-33 level was revealed in the deceased compared to the survivors [12.25 vs. 4.72; p = 0.021]. ROC statistics identified the initial level of IL-33 as a predictor of death with 11.19 as cut-off value (sensitivity, 80.0%; specificity, 80.0%; AUC = 0.805; p = 0.021). Conclusions: Following tissue damage, IL-33 is abundantly released in the serum of polytraumatized patients immediately after their injuries occurred. As initial IL-33 levels were particularly high in individuals experiencing both PLI and ARDS, IL-33 release after trauma seems to be involved in the promotion of ARDS and might serve already at admission as a solid indicator of impending death in polytraumatized patients.

The impact of polytrauma on sRAGE levels: evidence and statistical analysis of temporal variations.

BACKGROUND: According to recently published findings, levels of the soluble receptor of advanced glycation end products (sRAGE) and its clearance from the blood may reflect the evolution of lung damage during hospitalization. Thus, the objective of this study was to reveal the course of sRAGE levels over the first three posttraumatic weeks, focusing on the severity of thoracic trauma and the development of acute respiratory distress syndrome (ARDS) and/or pneumonia. METHODS: Twenty-eight consecutive surviving polytraumatized patients suffering thoracic trauma, age ≥ 18 years, Injury Severity Score ≥ 16, and directly admitted to our level I trauma center were enrolled in this prospective study. Blood samples were taken initially and on days 1, 3, 5, 7, 10, 14, and 21 during hospitalization. Luminex multi-analyte-technology was used for biomarker analysis. RESULTS: Common to all our patients was an almost continuous decline of sRAGE levels within the first five posttraumatic days. Day 0 levels in polytrauma victims with severe thoracic trauma were more than twice as high than in those suffering mild thoracic trauma (p = 0.035), whereas the difference between the two groups did not reach significance from day 1. Neither the development of ARDS and/or pneumonia nor the necessity of secondary surgery did result in significant differences in sRAGE levels between the subgroups with and without the particular complication at any time point. CONCLUSIONS: sRAGE levels assessed immediately after hospital admission might serve as a diagnostic marker for the vehemence of impacts against the chest and thus might be applied as an additional tool in diagnosis, risk evaluation, and choice of the appropriate treatment strategy of polytraumatized patients in routine clinical practice.

Introduction of a new repair technique in bony avulsion of the FDP tendon: A biomechanical study.

The purpose of this study was to determine the biomechanical characteristics of an innovative surgical technique based on a tension banding principle using a suture anchor in the repair of bony avulsions of the flexor digitorum profundus tendon. After injury simulation in 45 fresh frozen distal phalanges from human cadavers, repair was performed with minifragment screws, interosseous sutures and the innovative technique (15 per group). All repairs were loaded for a total of 500 cycles. Subsequently the specimens were loaded to failure. Load at failure, load at first noteworthy displacement (>2 mm), elongation of the system, gap formation at the avulsion site, and the mechanism of failure were assessed. The new techniques' superior performance in load at failure (mean: 100.5 N), load at first noteworthy displacement (mean 77.4 N), and gap formation (median 0 mm) was statistically significant, which implies a preferable rigidity of the repair. No implant extrusion or suture rupture during cyclic loading were recorded when the new technique was applied. This innovative repair technique is superior biomechanically to other commonly used surgical tendon reattachment methods, particularly with respect to an early passive mobilisation protocol. Further, due to its subcutaneous position, reduction of complications may be achieved.

A Novel Approach to Identify Polytraumatized Patients in Extremis.

INTRODUCTION: Due to the fact that early objective identification of polytraumatized patients in extremis is crucial for carrying out immediate life-saving measures, our objectives were to provide and scrutinize a definition that results in a particularly high mortality rate and to identify predictors of mortality in this group. MATERIALS AND METHODS: A polytraumatized patient (ISS ≥ 16) was classified "in extremis" if five out of seven parameters (arterial paCO2 > 50 mmHg, hemoglobin < 9.5 g/dl, pH value < 7.2, lactate level > 4 mmol/l, base excess < -6 mmol/l, shock index > 1, and Horowitz index < 300) were met. By applying this definition, polytraumatized patients (age ≥ 18 years), admitted to our level I trauma center within a time period of three years, were retrospectively allocated to the "in extremis" group and to an age-, gender-, and ISS-matched "non-in extremis" group for comparison. RESULTS: Out of 64 polytraumatized patients (mean ISS, 43.6), who formed the "in extremis" group, 36 patients (56.3%) died, thus revealing a threefold higher mortality rate than in the matched group (18.9%). Within the "in extremis" group, age and ISS were identified as predictors of mortality. CONCLUSION: Our definition might serve as a valuable early warning score or at least an impetus for defining polytraumatized patients in extremis in clinical practice.

Increased serum concentrations of soluble ST2 are associated with pulmonary complications and mortality in polytraumatized patients.

BACKGROUND: We sought to evaluate the role of soluble ST2 (suppression of tumorigenicity) serum concentrations in polytraumatized patients and its potential role as biomarker for pulmonary complications. METHODS: We included severely injured patients (injury severity score≥16) admitted to our level I trauma center and analyzed serum samples obtained on the day of admission and on day 2. Furthermore, patients with isolated thoracic injury and healthy probands were included and served as control groups. Serum samples were analyzed for soluble ST2 concentrations with a commercially available ELISA kit. RESULTS: A total of 130 patients were included in the present study. Five patients with isolated thoracic injury and eight healthy probands were further included. Serum analyses revealed significantly elevated concentrations of soluble ST2 in polytraumatized patients compared to patients suffering from isolated thoracic trauma and healthy probands. In polytraumatized patients who developed pulmonary complications (acute respiratory distress syndrome and pneumonia) and in patients who died, significantly higher serum concentrations of soluble ST2 were found on day 2 (p<0.001). Serum concentrations of soluble ST2 on day 2 were of prognostic value to predict pulmonary complications in polytraumatized patients (area under the curve=0.720, 95% confidence interval=0.623-0.816). Concomitant thoracic trauma had no further impact on serum concentrations of soluble ST2. CONCLUSIONS: Serum concentrations of soluble ST2 are upregulated following polytrauma. Increased concentrations were associated with worse outcome.

Treatment of air leak in polytrauma patients with blunt chest injury.

INTRODUCTION: Precise diagnostics and an adequate therapeutic approach are mandatory in the treatment of air leak in polytrauma patients with blunt chest trauma. The aim of this study was to evaluate the incidence, characteristics, and management of air leak following this injury pattern. PATIENTS AND METHODS: Data from 110 polytrauma patients was collected retrospectively. Fifty-four patients received initial treatment by chest tube placement for pneumothorax. These patients were classified into two groups, one with severe air leak and one with minor air leak. An evaluation of injury pattern, chest wall injuries in particular, duration of air leak, reason for drainage maintenance in place, hospital length of stay, ICU stay, ventilator duration, type of treatment, and the delay to surgical intervention was performed. RESULTS: Whereas 4 patients showed severe air leak and were subsequently scheduled for timely surgical intervention, the remaining 50 patients only showed minor air leak. Only 7 patients with minor air leak suffered from prolonged air leak (>5days), which spontaneously resolved in all of them after a mean duration of 7.7days (range 6-12days). Absence of a prolonged air leak resulted in a shorter length of stay and a shorter duration of mechanical ventilation, although no statistical significance was observed. CONCLUSIONS: Early spontaneous cessation of most minor air leaks as well as early surgical intervention for severe air leak lead to very satisfactory patient outcomes with a relatively short hospital stay in our patients. We therefore advocate early surgery for lacerations of the pulmonary parenchyma resulting in severe air leak, whereas minor air leaks can usually be treated conservatively.

Results of 167 consecutive cases of acetabular fractures using the Kocher-Langenbeck approach: a case series.

BACKGROUND: Acetabular fractures are quite challenging injuries for the orthopedic surgeon because of their low incidence and their deep and complex anatomy. The objective of this study was to evaluate surgeon-independent parameters that might influence radiographic outcome and early complication rates of high-energy acetabular fractures treated by open reduction and internal fixation via the Kocher-Langenbeck approach, the golden standard for posterior access. METHODS: One hundred sixty-seven consecutive patients (111 males and 56 females) with a mean age of 41.8 years and a mean follow-up period of 10 months were surgically treated by one experienced surgeon at a level I trauma center within 10 years. To quantify the radiographic outcome, the Matta, Brooker, and Epstein grades were used. Posttraumatic arthritis and avascular necrosis of the femoral head (defined as Helfet grades 3 or 4 and Ficat/Arlet stages 3 or 4, respectively) were evaluated. Furthermore, subgroup analyses according to fracture type, age, and gender were performed for each outcome measure and complication (infection, hemorrhagic shock, revision surgery, nerve damage, and need of a total hip arthroplasty). RESULTS: 65 A1, 34 A2, 51 B1, and 17 B2 fractures were identified according to the AO/ASIF classification. Of all patients, reduction was rated anatomic in 63.5%, imperfect in 22.2%, and poor in 14.4%. Degenerative changes were observed in 49.7%; 37.9% were affected by heterotopic ossification, 21.6% by posttraumatic arthritis, and 5.4% by avascular necrosis of the femoral head. Fifteen percent were diagnosed with a nerve damage, and 4.8% sustained an infection. Total hip arthroplasty was performed in 10.2%. Revision surgery due to secondary loss of reduction, seroma/hematoma, and wound infection was indicated in 6.0%. CONCLUSIONS: Fracture type, age, and gender are prognostic factors for the surgical outcome after ORIF of high-energy acetabular fractures.

Thoracic trauma and acute respiratory distress syndrome in polytraumatized patients: a retrospective analysis.

BACKGROUND: Although thoracic trauma has often been associated with the development of acute respiratory distress syndrome (ARDS) in general, its impact on ARDS in combination with severe concomitant injuries has still to be elucidated. Therefore, the objective of this study was to determine the frequency of thoracic trauma and ARDS in polytraumatized patients, and to evaluate the impact of thoracic trauma on the occurrence and the onset of ARDS. METHODS: Included in this retrospective cohort study were all polytraumatized patients over 18 years of age, with an injury severity score (ISS) of at least 16, who were admitted to our level I trauma center over a three-year time period. RESULTS: Two hundred and eighty-eight patients met the inclusion criteria. 54.9% suffered from thoracic trauma, 51.7% developed ARDS, 21.5% pneumonia and 0.7% pulmonary embolism. Independent of the ISS, the presence of thoracic trauma increased the odds of ARDS occurrence (OR=2.242; 95% CI: 1.381-3.640; P<0.001) and resulted in a significantly earlier onset of ARDS (median, day 2 vs. day 3; P<0.01). Of those patients suffering from ARDS, ventilation time and length of stay at the ICU were longer if a concomitant thoracic injury was present (P<0.001). In general, ARDS was diagnosed prior to pneumonia and was therefore identified as its risk factor (OR=11.033; 95% CI: 4.812-25.299; P<0.001). Finally, an overall mortality rate of 21.2% was observed, which was neither affected by thoracic trauma nor ARDS. CONCLUSIONS: Thoracic trauma was identified as major risk factor for ARDS occurrence and earlier onset in polytrauma victims.

Club cell protein 16 and cytokeratin fragment 21-1 as early predictors of pulmonary complications in polytraumatized patients with severe chest trauma.

BACKGROUND: Acute respiratory distress syndrome (ARDS) and pneumonia have a great impact on the treatment regimen of polytraumatized patients with severe chest trauma. The objective of our study was to determine whether biomarker levels assessed shortly after multiple trauma may predict the occurrence of these conditions. METHODS AND FINDINGS: Our patient population included 71 men and 30 women (mean age, 40.3 ± 15.8 years) with an Injury Severity Score that ranged from 17 to 59 and an Abbreviated Injury Scale Thorax of at least 3. They were admitted to our level I trauma center within one post-traumatic hour and survived for at least 24 hours after the trauma occurred. Thirty-five patients developed ARDS, 30 patients pneumonia and 21 patients both. Five individuals died during hospitalization. The levels of five selected biomarkers, which were identified by a literature search, were assessed at admission (initial levels) and on day 2 after trauma. We performed comparisons of medians, logistic regression analyses and receiver operating characteristic analyses for initial and day-2 levels of each biomarker. With regard to ARDS, initial levels of cytokeratin fragment 21-1, the soluble fragment of cytokeratin 19 (CYFRA21-1) and of the club cell protein 16 (CC16) provided significant results in each statistical analysis. With regard to pneumonia, each statistical analysis supplied significant results for both initial and day-2 levels of CYFRA21-1 and CC16. Consistently, initial CYFRA21-1 levels were identified as the most promising predictor of ARDS, whereas day-2 CC16 levels have to be considered as most appropriate for predicting pneumonia. CONCLUSIONS: CYFRA21-1 levels exceeding cut-off value of 1.85 ng/ml and 2.49 ng/ml in the serum shortly after multiple injury occurred may identify polytraumatized patients at risk for ARDS and pneumonia, respectively. However, CC16 levels exceeding 30.51 ng/ml on day 2 may allow a firmer diagnosis for the development of pneumonia.

The clinical benefit of a follow-up thoracic computed tomography scan regarding parenchymal lung injury and acute respiratory distress syndrome in polytraumatized patients.

PURPOSE: To evaluate the increase of parenchymal lung injury (PLI) volume between the initial and a follow-up computed tomography (CT) scan and to ascertain which of the 2 scans was more appropriate to predict acute respiratory distress syndrome (ARDS). MATERIAL AND METHODS: From 2011 to 2015, polytraumatized patients (≥18 years; ISS ≥ 16) directly admitted to our level I trauma center were included in our prospective study if a follow-up CT scan was possible 24 to 48 hours after the trauma. The PLI volume was measured using volumetric analysis. Statistical calculations were performed to identify patients at risk for ARDS. RESULTS: One hundred thirty patients (mean age, 41.3 years; mean ISS, 31.9) met the inclusion criteria. Median relative PLI volume was higher in the follow-up than in the initial CTs (9.65% vs 4.84%; P = .001). The ARDS developed in 42 patients (32.3%). Their initial PLI volume was higher compared with those without ARDS (11.23% vs 2.14%; P < .0001). The ARDS incidence increased with increasing initial PLI volume. Receiver operating characteristic statistics identified initial (area under the curve = 0.753) and follow-up relative PLI volume as a predictor for ARDS (area under the curve = 0.725). CONCLUSIONS: The CT scans performed directly after admission are sufficient to define patients at risk for ARDS. Therefore, solely the incidence of PLI does not justify a routine follow-up CT scan.

Soluble Receptor for Advanced Glycation End Products Quantifies Lung Injury in Polytraumatized Patients.

BACKGROUND: Biomarkers caused by blunt chest trauma might leak into the vascular compartment and therefore reflect the severity of parenchymal lung injury (PLI). Five promising proteins were preselected after a literature scan. The objective of our study was to identify a biomarker that is released abundantly into the serum shortly after trauma and reliably quantifies the loss of functional lung tissue. METHODS: Polytraumatized patients (aged ≥18 years, Injury Severity Score [ISS] ≥16) were included in our prospective observational study if they were admitted directly to our level I trauma center during the first hour after trauma occurred. Immediately after stabilizing the patient's condition, blood samples were taken and a whole-body computed tomographic (CT) scan was obtained. Biomarker levels were measured directly after admission and on day 2. PLI volume was calculated using volumetric analysis. RESULTS: One hundred thirty patients met the inclusion criteria. Compared with a matched healthy control population, median levels of the soluble receptor for advanced glycation end products (sRAGE) was almost 3 times higher and decreased by 41% on day 2. Higher initial median sRAGE levels were detected in patients with PLI compared with patients without PLI and in individuals with severe PLI compared with those with mild PLI. Spearman correlation analysis and a univariate linear log regression model revealed a significant correlation/equation between initial sRAGE levels and relative PLI volume. Receiver operating characteristic (ROC) statistics identified the initial sRAGE level as an indicator of severe PLI. CONCLUSIONS: sRAGE levels measured shortly after trauma seem to be a promising diagnostic tool to assess the severity of PLI in polytraumatized patients.

Extensor mechanism ruptures of the knee: differences in demographic data and long-term outcome after surgical treatment.

UNLABELLED: Extensor mechanism ruptures are rare injuries. Until now, only few reports of medium or long-term outcomes have been published. PURPOSE: The objective of this study was to quantify differences in demographic data and complications referring to patients with either quadriceps tendon ruptures (QTR) or patellar tendon (PTR) ruptures and to evaluate if complete functional restitution can be achieved after surgical treatment. METHODS: A search was conducted through the database of our level I trauma center in order to identify all patients surgically treated for QTRs or PTRs within 15 years and with a follow-up period of at least three years. Demographic data were collected by scanning their medical records. Of all patients available for a final check-up, their outcomes were assessed using the Knee Society Clinical Rating System (KSS), the Oxford Knee Score (OKS) and the Reduced WOMAC Function Scale (rWOMAC). Furthermore, patient perception (PP) was evaluated. RESULTS: 130 patients (93 QTRs and 43 PTRs) met the inclusion criteria. 8% of the QTR- and 13% of the PTR-patients suffered wound healing disorders/septic complications. 8% in the QTR-group sustained a rerupture. 62% of all patients were available for clinical evaluation, the mean follow-up period was 10.3 years in the QTR-group and 9.0 years in the PTR-group. In both groups good to excellent outcomes were revealed. Of the KSS-Knee, the mean score value was 93.1 in the QTR-group and 91.4 in the PTR-group; KSS-Function: 89.7/96.4; OKS: 14.6/13.1; rWOMAC: 95.7/98.3; PP: 88.5/93.3. QTR-patients suffering a rerupture had a significantly worse outcome in all scores except for the KSS-Knee (p≤0.026), whereas PTR-patients with healing disorders/septic complications showed a significant inferior outcome solely in the PP-scale (p=0.02).