Frank Hildebrand

Ten years of helicopter emergency medical services in Germany: Do we still need the helicopter rescue in multiple traumatised patients?

BACKGROUND Helicopter emergency medical service (HEMS) has been established in the preclinical treatment of multiple traumatised patients despite an ongoing controversy towards the potential benefit. Celebrating the 20th anniversary of TraumaRegister DGU(®) of the German Trauma Society (DGU) the presented study intended to provide an overview of HEMS rescue in Germany over the last 10 years analysing the potential beneficial impact of a nationwide helicopter rescue in multiple traumatised patients. PATIENTS AND METHODS We analysed TraumaRegister DGU(®) including multiple traumatised patients (ISS ≥ 16) between 2002 and 2012. In-hospital mortality was defined as main outcome. An adjusted, multivariate regression with 13 confounders was performed to evaluate the potential survival benefit. RESULTS 42,788 patients were included in the present study. 14,275 (33.4%) patients were rescued by HEMS and 28,513 (66.6%) by GEMS. Overall, 66.8% (n=28,569) patients were transported to a level I trauma centre and 28.2% (n=12,052) to a level II trauma centre. Patients rescued by HEMS sustained a higher injury severity compared to GEMS (ISS HEMS: 29.5 ± 12.6 vs. ISS GEMS 27.5 ± 11.8). Helicopter rescue teams performed more on-scene interventions, and mission times were increased in HEMS rescue (HEMS: 77.2 ± 28.7 min. vs. GEMS: 60.9 ± 26.9 min.). Linear regression analysis revealed that the frequency of HEMS rescue has decreased significantly between 2002 and 2012. In case of transportation to level I trauma centres a decrease of 1.7% per year was noted (p<0.001) while a decline of 1.6% per year (p<0.001) was measured for level II trauma centre admissions. According to multivariate logistic regression HEMS was proven a positive independent survival predictor between 2002 and 2012 (OR 0.863; 95%-CI 0.800-0.930; Nagelkerkes-R(2) 0.539) with only little differences between each year. CONCLUSIONS This study was able to prove an independent survival benefit of HEMS in multiple traumatised patients during the last 10 years. Despite this fact, a constant decline of HEMS rescue missions was found in multiple trauma patients due to unknown reasons. We concluded that HEMS should be used more often in case of trauma in order to guarantee the proven benefit for multiple traumatised patients.

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.

Development of a scoring system based on conventional parameters to assess polytrauma patients: PolyTrauma Grading Score (PTGS).

BACKGROUND The impact of conventional laboratory data to identify polytrauma patients at risk of complications is established. However, it has not been assessed in terms of prognostic accuracy for systemic complications (ARDS, organ failure). We therefore assessed the most predictive parameters for systemic complications and developed a scoring system for early grading of polytrauma patients. METHODS A population based trauma registry was used. INCLUSION CRITERIA age >16 years, Abbreviated Injury Score (AIS) of the abdomen or chest ≥ 3 points and treatment in an intensive care unit, or Injury Severity Score (ISS) ≥ 16 points. The primary endpoint was hospital mortality. Patients were graded according their risk of death: low risk of death (5-14% mortality), intermediate risk patients (15-39% mortality) and high risk (>40%). Routine clinical and laboratory parameters on admission were assessed to determine their specific relevance to describe the risk profile of the patient. Based on these data, a scoring system for the description of the clinical status was developed. Statistical analysis included uniand multivariate analysis. RESULTS 11.436 patients were included, the mean ISS was 22.7 ± 11.2 points, 73% were male, and 95.6% had blunt injuries. The most sensitive parameters were found to be the following ones: systolic blood pressure, INR, thrombocytes, base deficit, NISS, packed red blood cells administered. The multivariate analysis revealed the following threshold levels: BP 76-90 mmHg: r = 0.249, OR 1.283: Base deficit 8-10 r = 0.474, OR 1.606; INR 1.4-2 r = 0.160, OR 1.174; NISS 35-39 r = 0.9, OR 2.46; pBRC 3-14: r = 0.671, OR 1.957. The following ranges of score values were found to be associated with different patient status: <6 points: stable patients; 6-11 points: borderline condition; >11 points: unstable patients. When using this score, 80.6% were stable, 14.6% in a borderline condition and 4.8% unstable. CONCLUSION We developed a scoring system to discriminate polytrauma patients on admission that are at risk of systemic complications. Systolic blood pressure, INR, thrombocytes, base deficit, NISS, packed red blood cells administered are able to provide a prognosis of patients at risk of posttraumatic complications. Further prospective studies should be performed to verify this new scoring system.

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.

Relevance of induced and accidental hypothermia after trauma-haemorrhage-what do we know from experimental models in pigs?

Recent experimental research has either focused on the role of accidental hypothermia as part of the lethal triad after trauma or tried to elucidate the effects of therapeutically induced hypothermia on the posttraumatic course. Induced hypothermia seems to reduce the mortality in experimental models of trauma-haemorrhage. As potential mechanisms, a decrease of cellular metabolism, beneficial effects on haemodynamic function and an attenuation of the inflammatory response have been described. However, negative side effects of hypothermia have to be considered, such as impairment of the coagulatory function and immunosuppressive effects. Furthermore, the optimal strategy for the induction of hypothermia (magnitude, duration, timing, cooling rate, etc.) and subsequent rewarming remains unclear. Nevertheless, this piece of information is essential before considering hypothermia as a treatment strategy for severely injured patients. This review aims to elaborate the differences between accidental and induced hypothermia and to summarize the current knowledge of the potential therapeutic use of induced hypothermia suggested in porcine models of trauma-haemorrhage.

Classification of soft-tissue injuries in open femur fractures- Relevant for systemic complications?

BACKGROUND A broad range of systemic complications has been described to occur in patients with open major fractures. Various causes have been claimed to play a role. We therefore surveyed a nationwide trauma registry to assess risk factors associated with closed and various types of open femur fractures. METHODS This was a cohort study in a nationwide population-based prospective database. Inclusion criteria for selection from database are as follows: individuals with femur fracture, age 16 years or older, and survival until primary admission. Main groups included closed and open femur fracture. Patient demographics, injury severity (New Injury Severity Score), surgical fracture management, length of stay, and systemic complications (e.g., multiple organ failure [MOF], sepsis, mortality) were collected and statistically analyzed using SPSS statistics. Multivariate regression analysis was performed to stratify subgroups for the degree of open soft-tissue injury according to Gustilo and Anderson. RESULTS Among 32,582 documented trauma victims (January 1, 2002, to December 31, 2010), a total of 5,761 met the inclusion criteria. Main groups: 4,423 closed (76.8%) and 1,338 open femur fractures (23.2%). Open fractures subgroups were divided into I° (334, 28.1%), II° (526, 44.3%), and III° (328, 27.6%). Open fractures were associated with an increased risk of prehospital hemorrhagic shock (p = 0.01), higher resuscitation requirements (p < 0.001), MOF (p = 0.001), and longer in-hospital (p < 0.001) and intensive care stay (p = 0.001). While New Injury Severity Score values showed a minor increase per subgroup, the prevalence of MOF, sepsis, and mortality multiplied with the degree of open soft-tissue injury. Especially patients with Type III open femur fractures received mass transfusions (28.2%, p < 0.001), and mass transfusions were identified as independent predictor for sepsis (odds ratio [OR], 2.393; 95% confidence interval [CI], 1.821–3.143; p < 0.001) and MOF (OR, 2.966; 95% CI, 2.409–3.651; p < 0.001). Our data also indicate an increased mortality in patients with open femur managed outside Level I trauma centers (OR, 1.358; 95% CI, 1.018–1.812; p = 0.037). CONCLUSION Open femur fractures are associated with higher in-hospital complications related to incidence of MOF, associated intensive care unit stay, and hospital days when compared with closed femur fractures. For prevention of in-hospital complications, prompt hemorrhage control, surgical fracture fixation, cautious blood management, and triage to a Level I trauma center must be considered. LEVEL OF EVIDENCE Epidemiologic/prognostic study, level II.

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.

Detecting severe injuries of the upper body in multiple trauma patients

BACKGROUND The clavicle limits the upper thoracic cage and connects the body and upper extremities. The clavicle is easy to examine and is visible on standard emergency room radiographs. We hypothesized that clavicular fracture in polytrauma patients would indicate the presence of further injuries of the upper extremities, head, neck, and thorax. METHODS A population-based trauma registry was used. All patients were documented between 2002 and 2013. Inclusion criteria were age ≥16 y and injury severity score (ISS) ≥16. Patients were divided into two groups according to the presence or absence of a clavicular fracture (group C+ and group C-). Scoring was based on the abbreviated injury scale, ISS, and new injury severity score. Trauma mechanisms, demographics, and the posttraumatic clinical course were compared. RESULTS In total, 4790 patients with clavicular fracture (C+) and 41,775 without (C-) were included; the mean ISS was 30 ± 11 (C+) versus 28 ± 12 (C-). Patients with clavicular fracture had a longer stay on the intensive care unit with 12 ± 14 versus 10 ± 13 d. Injuries to the thoracic wall, severe lung injuries as well as injuries to the cervical spine were significantly increased in C+ patients. Thoracic injuries as well as injuries of the shoulder girdle and/or arm showed an increased abbreviated injury scale in the C+ group. CONCLUSIONS A clinically relevant coincidence of clavicular fractures with injuries of the chest and upper extremity was found. As clavicular fractures can be diagnosed easily, it might also help to reduce the incidence of missed injuries of the chest and upper extremity. Therefore, special attention should be paid on thoracic as well as upper extremity injures during the second and tertiary surveys in case of clavicular fractures.

External fixation in the elderly

Orthopaedic trauma is an increasingly common problem in geriatric patients. As demands of daily life and recreational activities are increasing in these patients, surgeons need to be able to manage geriatric fractures to achieve good functional results. Reduced bone quality in the elderly presents a considerable challenge and may preclude the use of established surgical stabilisation techniques that are performed in younger trauma patients. Furthermore, pre-existing medical conditions and considerable comorbidities in the elderly could complicate standard surgical procedures that younger patients would be offered. In this respect, application of external fixators represents a validated, minimally-invasive treatment opportunity. This review article summarises the use of external fixation in geriatric trauma patients for wrist fractures, proximal femoral fractures, pelvic fractures, and ankle fractures. Modern modifications, like pin coating with hydroxyapatite, and aspects of pin care will be discussed.