Klemens Horst

The long-term clinical outcome after pelvic ring injuries

We report the functional and socioeconomic long-term outcome of patients with pelvic ring injuries. We identified 109 patients treated at a Level I trauma centre between 1973 and 1990 with multiple blunt orthopaedic injuries including an injury to the pelvic ring, with an Injury Severity Score (ISS) of ≥ 16. These patients were invited for clinical review at a minimum of ten years after the initial injury, at which point functional results, general health scores and socioeconomic factors were assessed. In all 33 isolated anterior (group A), 33 isolated posterior (group P) and 43 combined anterior/posterior pelvic ring injuries (group A/P) were included. The mean age of the patients at injury was 28.8 years (5 to 55) and the mean ISS was 22.7 (16 to 44). At review the mean Short-Form 12 physical component score for the A/P group was 38.71 (22.12 to 56.56) and the mean Hannover Score for Polytrauma Outcome subjective score was 67.27 (12.48 to 147.42), being significantly worse compared with the other two groups (p = 0.004 and p = 0.024, respectively). A total of 42 patients (39%) had a limp and 12 (11%) required crutches. Car or public transport usage was restricted in 16 patients (15%). Overall patients in groups P and A/P had a worse outcome. The long-term outcome of patients with posterior or combined anterior/posterior pelvic ring injuries is poorer than of those with an isolated anterior injury.

Indications for bullet removal: overview of the literature, and clinical practice guidelines for European trauma surgeons

PurposeThe incidence of gunshot wounds from civilian firearms is increasing. Despite this fact, guidelines on indications for bullet removal are scarce. In this analysis, we combine an overview of the available literature in these rare entities with our experiences in our own clinical practices.MethodsWe conducted a systematic literature search of computerized bibliographic databases (Medline, EMBASE, and the Cochrane Central Register). The local experience of the authors was reviewed in light of the available literature.Results145 full-text articles were suitable for further evaluation. Only six retrospective studies were available, and no prospective study could be retrieved. Most of the articles were case reports. In the South African co-author’s own clinical practice, approximately 800 patients are treated per year with gunshot wounds.ConclusionsIn summary, there are only a few clear indications for bullet removal. These include bullets found in joints, CSF, or the globe of the eye. Fragments leading to impingement on a nerve or a nerve root, and bullets lying within the lumen of a vessel, resulting in a risk of ischemia or embolization, should be removed. Rare indications are lead poisoning caused by a fragment, and removal that is required for a medico-legal examination. In all other cases the indication should be critically reviewed.

Impact of Helicopter Emergency Medical Service in Traumatized Patients: Which Patient Benefits Most?

Introduction The Helicopter Emergency Medical Service (HEMS) was established for the prehospital trauma care of patients. Improved rescue times and increased coverage areas are discussed as specific advantages of HEMS. We recently found evidence that HEMS exerts beneficial effects on outcomes for severely injured patients. However, it still remains unknown which group of trauma patients might benefit most from HEMS rescue. Consequently, the unique aim of this study was to reveal which patients might benefit most from HEMS rescue. Methods Trauma patients (ISS ≥9) primarily treated by HEMS or ground emergency medical services (GEMS) between 2002 and 2012 were analysed using the TraumaRegister DGU. A multivariate regression analysis was used to reveal the survival benefit between different trauma populations. Results The study included 52 281 trauma patients. Of these, 68.8% (35 974) were rescued by GEMS and 31.2% (16 307) by HEMS. HEMS patients were more severely injured compared to GEMS patients (ISS: HEMS 24.8±13.5 vs. GEMS 21.7±18.0) and more frequently suffered traumatic shock (SBP sys <90mmHg: HEMS 18.3% vs. GEMS 14.8%). However, logistic regression analysis revealed that HEMS rescues resulted in an overall survival benefit compared to GEMS (OR 0.81, 95% CI [0.75–0.87], p<0.001, Nagelkerkes R squared 0.526, area under the ROC curve 0.922, 95% CI [0.919–0.925]). Analysis of specific subgroups demonstrated that patients aged older than 55 years (OR 0.62, 95% CI [0.50–0.77]) had the highest survival benefit after HEMS treatment. Furthermore, HEMS rescue had the most significant impact after ‘low falls’ (OR 0.68, 95% CI [0.55–0.84]) and in the case of minor severity injuries (ISS 9–15) (OR 0.66, 95% CI [0.49–0.88]). Conclusions In general, trauma patients benefit from HEMS rescue with in-hospital survival as the main outcome parameter. Focusing on special subgroups, middle aged and older patients, low-energy trauma, and minor severity injuries had the highest survival benefit when rescued by HEMS. Further studies are required to determine the potential reasons of this benefit.

Long-Term Effects of Induced Hypothermia on Local and Systemic Inflammation - Results from a Porcine Long-Term Trauma Model

Background Hypothermia has been discussed as playing a role in improving the early phase of systemic inflammation. However, information on the impact of hypothermia on the local inflammatory response is sparse. We therefore investigated the kinetics of local and systemic inflammation in the late posttraumatic phase after induction of hypothermia in an established porcine long-term model of combined trauma. Materials & Methods Male pigs (35 ± 5kg) were mechanically ventilated and monitored over the study period of 48 h. Combined trauma included tibia fracture, lung contusion, liver laceration and pressure-controlled hemorrhagic shock (MAP < 30 ± 5 mmHg for 90 min). After resuscitation, hypothermia (33°C) was induced for a period of 12 h (HT-T group) with subsequent re-warming over a period of 10 h. The NT-T group was kept normothermic. Systemic and local (fracture hematoma) cytokine levels (IL-6, -8, -10) and alarmins (HMGB1, HSP70) were measured via ELISA. Results Severe signs of shock as well as systemic and local increases of pro-inflammatory mediators were observed in both trauma groups. In general the local increase of pro- and anti-inflammatory mediator levels was significantly higher and prolonged compared to systemic concentrations. Induction of hypothermia resulted in a significantly prolonged elevation of both systemic and local HMGB1 levels at 48 h compared to the NT-T group. Correspondingly, local IL-6 levels demonstrated a significantly prolonged increase in the HT-T group at 48 h. Conclusion A prolonged inflammatory response might reduce the well-described protective effects on organ and immune function observed in the early phase after hypothermia induction. Furthermore, local immune response also seems to be affected. Future studies should aim to investigate the use of therapeutic hypothermia at different degrees and duration of application.

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.

The synthetic antimicrobial peptide 19-2.5 attenuates septic cardiomyopathy and prevents down-regulation of SERCA2 in polymicrobial sepsis

An impairment of cardiac function is a key feature of the cardiovascular failure associated with sepsis. Although there is some evidence that suppression of sarcoplasmic reticulum Ca2+-ATP-ase (SERCA2) contributes to septic cardiomyopathy, it is not known whether prevention of the down-regulation of SERCA2 improves outcome in sepsis. Thus, we investigated whether the administration of the synthetic antimicrobial peptide Pep2.5 may attenuate the cardiac dysfunction in murine polymicrobial sepsis through regulating SERCA2 expression. We show here for the first time that the infusion of Pep2.5 reduces the impaired systolic and diastolic contractility and improves the survival time in polymicrobial sepsis. Preservation of cardiac function in sepsis by Pep2.5 is associated with prevention of the activation of NF-κB and activation of the Akt/eNOS survival pathways. Most notably, Pep2.5 prevented the down-regulation of SERCA2 expression in a) murine heart samples obtained from mice with sepsis and b) in cardiomyocytes exposed to serum from septic shock patients. Thus, we speculate that Pep2.5 may be able to prevent down-regulation of cardiac SERCA2 expression in patients with sepsis, which, in turn, may improve cardiac function and outcome in these patients.

Standards of external fixation in prolonged applications to allow safe conversion to definitive extremity surgery: the Aachen algorithm for acute ex fix conversion

External fixation has become an important tool in orthopedic surgery. Technology has improved the design and material as well as the construct of the fixator. As most patients are converted from external fixation to definite stabilization during later clinical course, prevention of complications such as infection is of high importance. Based on the current literature, principles of temporary external fixation were summarized. We focused on minimizing the risk of infection and introduce a standardized algorithm how to proceed when converting from external to internal fixation, which also was examined for effectiveness.

A Meta-Analysis of Operative Versus Nonoperative Treatment In 463 Scapular Neck Fractures

Background and Aims: Treatment of scapular neck fractures remains controversial. Advantages of surgical treatments, such as anatomical restoration of fracture displacement, are counterbalanced by approach morbidity. We conducted a meta-analysis of 463 scapular neck fractures and compared clinical, functional, and radiographical outcomes in operatively and nonoperatively treated scapular neck fractures. Material and Methods: A literature search was conducted, including the databases PubMed/MEDLINE, Embase, and the Cochrane Database of Systematic Reviews. Manuscripts were included if they reported a precise description of treatment, complications, functional outcomes, and/or radiographic evaluation. Data about day-to-day activities, level of pain-freeness, range of motion, functional grading, and radiographical assessment were pooled and compared using fixed effects models. Results and Conclusions: A total of 22 manuscripts were relevant, including 1 prospective cohort study and 21 retrospective studies. The studies showed a high heterogeneity in the result assessment. Most patients had concomitant injuries. In total, 234 out of the 463 fractures were treated operatively. Pain-freeness and radiographic outcome measurements were significantly better in the operatively treated group, whereas range of motion was significantly improved in the nonoperative treated patients. Complication rate for surgical treatment was about 10%. From the achievable data, there was no bias detected when comparing the two treatment groups. However, those data could not be analyzed for all included studies. For the same reason, the role of additional surgical treatment for concomitant injuries to the shoulder girdle could not be cleared completely. Caution should be exercised, and individual injury patterns have to be taken into consideration when considering the best treatment options.

Microcirculation in open vs. minimally invasive dorsal stabilization of thoracolumbar fractures

Standard open and percutaneous minimally invasive surgical procedures co-exist in the treatment of fractures of the thoracolumbar spine. Shorter skin incisions just above the pedicles are used in minimally invasive procedures. Full-length skin incisions and invasive preparations are applied in the standard open approach. While both methods show equivalent rates of intraoperative surgical complications and comparable clinical and radiological outcomes, blood loss and operation time have shown to be decreased in minimally invasive treatment. However, no study so far has investigated differences in microcirculation. This study hypothesized less impairment of microcirculation in the minimally invasive approach compared to the open approach and an improvement of microcirculation over time. A prospective cohort study was conducted using non-invasive laser-Doppler spectrophotometry (an O2C “oxygen to see” device) for measurement of cutaneous and subcutaneous blood oxygenation (SO2), haemoglobin concentration (Hb), and blood flow at depths of 2, 8, and 15 mm at six locations on the skin. Measurements were performed before surgery, 8 and 24 h after surgery, and 2, 4, 7, 12 and 20 days after surgery, however the number of patients measured decreased towards the later time points. Forty patients were included in the study, 20 with each approach (18 females and 22 males). Pair-wise comparison of the types of surgical procedure for each measurement point revealed a significantly higher flow value in the minimally invasive group at one of the measurement points located between the incisions (P = .041). The point-wise analyses of SO2 and Hb did not show significant differences between the approaches. In conclusion, significantly albeit moderately higher flow values could be found in minimally invasive procedures compared to open operations of thoracolumbar fractures in the area of skin that is spared by the incisions.

Development of a standardized trauma-related lung injury model

BACKGROUND The pathophysiology of acute lung injury is multifactorial, and the mechanisms are difficult to prove. We have devised a study of two known and standardized animal models (hemorrhagic shock [HS] and oleic acid [OA]) to more closely reproduce the pathophysiology of posttraumatic acute lung injury. MATERIAL AND METHODS Pressure-controlled HS (group HS) was performed by withdrawing blood over 15-min until mean arterial pressure reached 35 mm Hg for 90 min. In an additional group, HS and standardized lung injury induced by OA were combined (group lung injury [HS + OA]). After the shock period, both groups were resuscitated over 15 min by transfusion of the removed blood and an equal volume of lactate Ringer solution. The end point was 6 h. Plasma interleukin (IL)-6, keratinocyte chemoattractant (KC), IL-10, monocyte chemoattractant protein-1 (MCP-1), and lung histology were carried out. RESULTS The posttraumatic lung injury group demonstrated significantly higher IL-6 levels when compared with HS group (744.8 ± 104 versus 297.7 ± 134 pg/mL; P = 0.004). Histologic analysis confirmed diffuse alveolar congestion and moderate-to-severe lung edema in animals with HS + OA. Lung injury was mild in mice with isolated HS or OA injection. CONCLUSIONS We established a posttraumatic lung injury model combining two different standardized protocols (HS and OA). This model leads to pronounced inflammation and lung injury. This model allows the analysis of the dynamics of sterile lung injury and associated organ dysfunction.