[Deployment and efficacy of ground versus helicopter emergency service for severely injured patients. Analysis of a nationwide Swiss trauma center]. / Status quo der Boden- und Luftrettung schwerverletzter Patienten. Analyse eines überregionalen Schweizer Traumazentrums.

The influence of the transport mode, i.e. Helicopter Emergency Medical Service (HEMS) versus ground-based Emergency Medical Service (EMS) on the mortality of multiple trauma patients is still controversially discussed in the literature. In this study a total of 333 multiple trauma patients treated over a 1-year period in a level I trauma center in Switzerland were analyzed. Using the newly established revised injury severity classification (RISC) score there was a tendency towards a better outcome for patients transported by HEMS (standardized mortality ratio 1.06 for HEMS versus 1.29 for EMS). Overall a short preclinical time and the presence of an emergency physician (EP) were associated with a better outcome.

Successful rotational thromboelastometry-guided treatment of traumatic haemorrhage, hyperfibrinolysis and coagulopathy.

Transfusion of allogeneic blood products is associated with increased morbidity and mortality. Therefore, strategies for reducing transfusion of these products during trauma management are valuable. We report a case of severe blunt abdominal trauma, successfully treated with antifibrinolytic medication and fibrinogen concentrate. Rotational thromboelastometry (ROTEM) was used to identify hyperfibrinolysis and afibrinogenaemia. In order to achieve haemostasis, over a 3-h period, the patient received a total of 1 g of tranexamic acid, 7 U of packed red blood cells, 16 g of fibrinogen concentrate (Haemocomplettan P), 3500 ml of colloids and 5500 ml of lactated Ringer's solution. Together with surgical measures, this treatment stopped the bleeding and stabilised the patient. There was no transfusion of either fresh-frozen plasma or platelets. The limited need for allogeneic blood products is of particular interest, and clinical studies of the approach used here appear to be warranted.

The influence of standardisation and task load on team coordination patterns during anaesthesia inductions.

BACKGROUND: The use of different forms of coordination according to situational demands plays a crucial role in teams working in complex environments. This study aimed to describe patterns of coordinative actions (CAs) as they occur during anaesthesia induction and to analyse the influence of two crucial situational factors on these patterns, namely the amount of existing standards and the level of task load. METHODS: 23 anaesthesia inductions were videotaped, and CAs of the anaesthesia teams were coded. The coding system distinguished between implicit and explicit coordination, coordination via leadership and heedful inter-relating as the individual effort to reach smooth coordination. Five phases within anaesthesia inductions were determined according to their level of standardisation and task load. RESULTS: Overall, 67.7% of all CAs were rated as explicit CA and 32.3% as implicit CAs. When we considered the duration of those CAs, we found the reverse tendency (coordination was explicit 40% of the time and implicit 60% of the time). In highly standardised phases, we observed less explicit coordination, less leadership behaviour and less heedful interrelating compared with less standardised phases. In high-task-load phases, we observed more heedful interrelating than in low-task-load phases. CONCLUSIONS: The anaesthesia teams relied greatly on implicit coordination, which contrasts with findings indicating a performance benefit through explicit coordination in other work settings. Standardisation in the form of written departmental directives may have a supportive effect on coordination by partially substituting for other forms of coordination. The effect of high task load should be tested further in a simulator setting, where high task load can be induced in a more controlled fashion.

[Participation--oriented analysis of the anesthesia workplace. A work system for anesthesia in a multidisciplinary operating room]. / Beteiligungsorientierte Arbeitsplatzanalyse. Schwachstellen im Arbeitssystem der Anästhesie in einem multidisziplinären OP-Trakt.

INTRODUCTION: The aim of this study was the detection and understanding of weak points in the ergonomic design of anaesthesia workplaces in a multidisciplinary operating room facility. METHODS: Analysis of workplaces and of working processes by means of observations, computer-supported task recording and video-photo documentation. During guided interviews the participants were provided with material for naming-by-pointing and drawing. Subsequently, the background of the problems encountered and possible improvements were visualised. RESULTS: Important deficits were devices not positioned within reach and view, difficulties in operating the lines connecting the patient and the devices, and inconsistent workplace layouts. These were caused by erroneous planning of the facility and disregarding ergonomic principles in equipment design. The initial improvements implemented were the development of a new concept for a flexible equipment positioning and the design of a tool for cable handling. DISCUSSION AND CONCLUSION: Although from the very beginning of the study the anaesthesia personnel quoted the handling of the lines connecting patients and devices as the main cause for working difficulties, the external ergonomist could contribute to a broader view of the problems. The method presented here initiated a mutual learning process between ergonomist and users and resulted in a common understanding of the problems and their causes. Compared to the traditional consulting process, more time and efforts were necessary but were offset by the users' acceptance of the improvements and the prevention of design errors.

[Epidemiology of internal knee injuries in Alpine skiing]. / Epidemiologie von Kniebinnenverletzungen beim alpinen Skisport.

The incidence of sport injuries in Switzerland is twice as high compared to traffic injuries. Soccer and alpine skiing play the most important role in sport injuries. For the last twenty winter seasons all winter sport injuries were analysed at the hospital of Davos. About 85% are injuries caused by alpine skiing resulting in a total of 24,684 for the last twenty years. There is a great decline in the incidence of lower leg fractures with a contrary development of knee injuries. The treatment-quotient (amount of knee injuries in alpine skiers per 10(4) kilometers of vertical drop skied) has increased over the last seasons. Nowadays one part of four skiing injuries is an injury of the knee ligaments. In skiing areas favored by beginners, we have observed an incidence of knee ligament injuries three times as high compared to other areas. Since 1986 we have evaluated 206 patients operated for knee ligament injuries, 44% with unidirectional and 56% with multidirectional instabilities. We report about the preoperative data.

[Epidemiology, treatment and follow-up of acute ligamentous knee injuries in Alpine skiing]. / Epidemiologie, Behandlung und Verlaufsbeobachtung frischer ligamentärer Kniebinnenverletzungen im alpinen Skisport.

In Switzerland the incidence of sport injuries is twice as high as traffic injuries. Soccer and alpine skiing are the major reasons for such injuries. Nowadays one out of four skiing injuries is an injury of the knee ligaments. Especially in skiing areas favored by beginners, we observed an incidence of knee ligament injuries three times as high compared to other areas. Since 1986 we evaluated 206 patients which were operated for knee ligament injuries. In 44% the direction of instability was unidirectional, most of them in the anterior direction. 115 patients had combined instabilities, 86% of those were anteromedial. 179 patients (87%) were followed up for at least 20 months. The knee was evaluated with the scoring system of the OAK (Orthopädische Arbeitsgruppe Knie der Schweizerischen Gesellschaft für Orthopädie) and judged by four criterias (pain/swelling; movement/force; stability and function). As expected, unidirectional instabilities show better results than multidirectional. The mean value of the total score for isolated medial collateral injuries was 95.3 of 100, for isolated anterior instabilities 90.4 and for combined antero-medial instabilities 86.7 Altogether 2/3 of the patients showed very good results in stability but, 4/5 showed good results in function, so 4/5 of the patients and their physicians considered the final result as good to very good and 2/3 of those patients are back to sports, only two percent do no more sports at all.

[Incidence and treatment of fresh connective tissue injuries of the knee in winter sports]. / Häufigkeit und Behandlung frischer Kniebinnenverletzungen im Wintersport.

For the last 18 years 21,808 alpine skiing injuries have been treated at the hospital of Davos. There is a great decline in the incidence of lower leg fractures with a contrary development of knee ligament injuries. Today half of the lower leg injuries are knee injuries. To ameliorate the documentation of all patients with acute injuries of the knee ligaments we are using a detailed questionnaire, including the mechanism of injury, release of the safety binding, skiing ability, pattern of instability and the techniques of treatment. We report of the evaluation of 145 patients with knee ligament injuries. It is the aim of that protocol to follow up all these cases up to 5 years.

Plasminogen activator in normal and tumor-bearing mice.

The plasminogen activator levels of a series of murine tumors commonly used in cancer drug screening were determined and compared to the levels found in normal mouse tissues. Tumors high in plasminogen activator included the B16 and colon 26. The Lewis lung and M5076 carcinoma showed an intermediate level of activity, while the plasminogen activator activity in the L1210 leukemia and colon 38 was barely elevated above background. The specific activity of the enzyme (per micrograms protein) in extracts of B16 and colon 26 was three or four times higher than in the most active normal organs surveyed (kidney, lung, brain and intestine). The high level of plasminogen activator activity measured in extracts of the B16 tumor was reflected in a substantial elevation of the levels of fibrin degradation products in the serum of mice carrying this tumor. This result suggests that the tumor-associated plasminogen activator activity is less subject to inhibitory controls in vivo than is the plasminogen activator of most normal tissues, since the total mass of the tumor was far less than the total mass of the fibrinolytically active tissues, and yet the bulk of the fibrin degradation products were caused by the tumor. We conclude that the high levels of plasminogen activator activity which are observed in many human tumors are found only in some of the transplantable murine tumors. Since this enzyme is active at an increased level in vivo in mice carrying the B16 tumor, plasminogen activator may be a suitable target for selective, enzyme-activated chemotherapy with this tumor test system.