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- Klinik und Poliklinik für Chirurgie Abt. für Unfall- und Wiederherstellungschirurgie (3) (remove)
Compared to gun control legislation in Germany, which is supposed to be one of the most stringent in Europe, gun control legislation in Vietnam is by far stricter. Private possession of guns is not possible in Vietnam. One key point in the German weapons act is the allowance for certain facilitations for airguns that impart kinetic energy of less than 7.5 J to the projectile. These airguns are freely available for purchase by persons 18 years of age or older. The 7.5 J limit is applied to airguns without further efinition of projectile characteristics like projectile head, projectile shape or projectile mass. In the course of a possible relaxation of gun control and facilitation of private gun ownership (especially of airguns) in Vietnam, an implementation of a kinetic energy limit, similar to the German 7.5 J limit, is conceivable. It was the aim of this cumulative doctoral thesis to investigate if this energy limit was a sufficient threshold to estimate the dangerousness of a weapon or projectile, especially in cases where the characteristics of the projectiles are fundamentally different from the “standard” projectiles which were basis for the implementation of this energy threshold in the German weapons act in 1968. The first study investigated basic ballistic parameters of plastic-sleeved composite projectiles in comparison to standard diabolo pellets. Although overall results were inconsistent, for some projectile–weapon combinations (particularly for spring-piston air guns), a significant change of the kinetic energy (− 53 up to + 48 %) to the reference projectile was observed. For some projectile types the legal limit of 7.5 J was exceeded by far. The second study focused on an uncommon discarding sabot airgun projectile (SUSSEX SABO). It was demonstrated, that the sabot principle works properly in high power airguns (E > 17 J), but separation of the core projectile from the sabot cup was also observed in mid- (E = 12.5 J) and low-energy (E < 7.5 J) airguns. While muzzle velocity and kinetic energy values of discarded sabot projectiles are comparable to conventional diabolo pellets, energy density (ED) and penetration capacity are significantly higher. Finally, the ballistic performance of a carbon dioxide-actuated arrow pistol (Arcus Arrowstar) was investigated. Compared to conventional diabolo pellets of a similar kinetic energy level, the penetration depth of this arrow projectile was increased by approximately 35 %. This high penetration capacity was mainly caused by the uncommon projectile characteristics (high cross-sectional density q and pointed arrow head). The findings of this work reveal that special projectile types, like the plastic-sleeved composite pellets, might substantially increase the muzzle energy of airguns. Other uncommon projectile types (like the SUSSEX SABO projectile or the Arcus Arrowstar projectile) exert a higher penetration capacity whereas kinetic energy is similar to standard diabolo pellets and is still beneath the legal limit. For these uncommon projectile types, the 7.5 J limit implemented in the German weapons act is not a sufficient threshold. As demonstrated, next to kinetic energy E and energy density ED, the characteristics of the projectile influence their ballistic parameters. So it is strongly recommended to specify legal kinetic energy limits in gun control legislation in greater detail. The design characteristics of the projectiles (cross-sectional density q and design of the projectile head) should be appropriately taken into consideration.
Primary Pan-CT is associated with improved clinical course and outcome in polytrauma patients
(2012)
The early clinical management of patients with polytrauma remains challenging. Clinical examination is unreliable in identifying the presence and severity of injuries, and diagnostic imaging plays a central role in the evaluation of the injury pattern. In the last decade, whole body multi slice computed tomography (Pan-CT) performed immediately after admission gained recognition in Europe and United States. Its utility and value, given the lack of accuracy data and concerns about unnecessary exposure to radiation, is undefined. The primary objective of this retrospective cohort study was to compare survival of multiple trauma (polytrauma) patients (Injury Severity Score [ISS] ≥ 16) prior to (1999 - 2002) and after (2002 - 2004) the introduction of a Pan-CT-based trauma resuscitation algorithm at a maximum care university medical centre. Secondary objectives were to compare the complication rates and duration of intensive care treatment. The study included 123 patients (mean age 34.6 years [SD 16.8], mean ISS 26.7 [SD 8.7]) in the control and 104 (mean age 39.8 years [SD 20.0], mean ISS 28.6 [SD 10.5]) patients in the intervention period. Die Baseline criteria were well balanced amongst both cohorts except for age (34.6 versus 39.8 years, p = 0.034). Both cohorts had a similar predicted probability of survival using the TRISS method (77.5 versus 77.6%, p = 0.979). Raw mortality decreased markedly but not statistically significantly in Pan-CT cohort (17.9 versus 11.5%, risk ratio (RR) 0.65, 95% confidence interval (CI) 0.34 - 1.24). However, after adjustment for injury severity, by mortality odds ratio of 0.40 (95% CI 0.17 – 0.95, p = 0.038) Pan-CT patients were 2.5 times more likely to survive. The mean difference in the duration of ICU treatment (5.1, 95% CI 1.2 – 9.0 days), days on respirator (5.3, 95% CI 2.0 - 8.6), and number of complications (0.4, 95% CI 0.2 – 0.8) was statistically significant and in favour of the Pan-CT-period.
Severe trauma results in alterations in immune functions, correlated with a dysbalanced cytokine synthesis. This imbalance endangers severely injured patients for post-traumatic complications such as MODS, liver failure, renal dysfunction and ARDS. IL-10, a powerful immunosuppressive cytokine, plays a central role in the immune response after severe trauma. The relevance of IL-10 for single and multiple organ failure was studied in a prospective study at a level I trauma center. Blood was systematically obtained from a total of 118 severely injured [median (IQR) ISS=34 (27-34)] patients. IL-10 plasma levels were measured by ELISA. Patients showed elevated IL-10 levels throughout the whole observation period of 5 days. IL-10 plasma levels rose rapidly after trauma and gradually declined towards day 5. Patients who developed complications demonstrated significantly elevated IL-10 levels compared with patients who did not. The odds of developing MODS were 9.6 times greater in patients with IL-10 plasma levels higher than 124 pg/mL 6 hours after arrival at the ICU. Multivariate analysis showed that IL-10 plasma levels >124 pg/mL at time-point 6h, severe head injury and an arterial pH <7.34 were simultaneously significant predictors of the development of MODS in severely injured patients. The dynamic with rapid increase and gradual decline in IL-10 plasma levels indicated that IL-10 is a marker of the initial damage to the organism caused by trauma, rather than a marker of somatic dysregulations.