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1.
Arch Orthop Trauma Surg ; 143(10): 6177-6192, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37314526

ABSTRACT

BACKGROUND: Traumatic hemipelvectomies are rare and serious injuries. The surgical management was described in several case studies, with primary amputation often performed to save the patient's life. METHODS: We report of two survivors with complete traumatic hemipelvectomy resulting in ischemia and paralyzed lower extremity. Due to modern emergency medicine and reconstructive surgery, limb salvage could be attained. Long-term outcome with quality of life was assessed one year after the initial accident. RESULTS AND CONCLUSIONS: The patients were able to mobilize themselves and live an independent life. The extremities remained without function and sensation. Urinary continence and sexual function were present and the colostomy could be relocated in both patients. Both patients support limb salvage, even having difficulties and follow-up treatments. Concomitant cases are required to consolidate the findings. LEVEL OF EVIDENCE: IV.


Subject(s)
Hemipelvectomy , Plastic Surgery Procedures , Humans , Hemipelvectomy/methods , Limb Salvage , Quality of Life , Amputation, Surgical , Retrospective Studies , Treatment Outcome
2.
BMC Musculoskelet Disord ; 23(1): 1008, 2022 Nov 23.
Article in English | MEDLINE | ID: mdl-36419124

ABSTRACT

INTRODUCTION: Traumatic lacerations of the prepatellar (PB) and olecranon bursa (OB) are common injuries. The aim of this study was to gain descriptive data and to identify risk factors associated with complications that made revision surgery after primary bursectomy necessary. MATERIAL AND METHODS: In this retrospective monocentric study at a level I trauma center, all patients with traumatic lacerations of the PB or OB who were treated with primary surgical bursectomy from 2015 to 2020 were analyzed. RESULTS: 150 consecutive patients were included. In 44% of cases, the PB was affected (n = 66), in 56% the OB (n = 84). The reoperation rate after surgical bursectomy was 10.7% (n = 16). The main cause of reoperation was wound infection (50%; n = 8). The most common pathogen of postoperative infections was Staphylococcus aureus (87.5%). Several comorbidities have been identified as risk factors for reoperation after primary surgical bursectomy, such as heart diseases, arterial hypertension, the use of antihypertensives and anticoagulation. In contrast, surgical expertise, use of drains, postoperative immobilization, and postoperative antibiotics had no statistically significant effect. A significantly higher postoperative infection rate (17.6%) was observed in patients who were operated more than 48 h after initial trauma. CONCLUSIONS: Given the limited recommendations for therapy of these common injuries, further investigations should focus on standardized therapeutic options for lacerations of the PB or OB. Delayed surgical interventions after trauma were associated with higher complication rates. Therefore, urgent surgery within 48 h after trauma may help to prevent revisions. LEVEL OF EVIDENCE: Level of evidence IV.


Subject(s)
Bursitis , Lacerations , Olecranon Process , Humans , Olecranon Process/surgery , Reoperation , Lacerations/surgery , Retrospective Studies , Bursitis/surgery , Risk Factors
3.
An Acad Bras Cienc ; 94(suppl 4): e20210434, 2022.
Article in English | MEDLINE | ID: mdl-36477818

ABSTRACT

Aiming to test the capacity of retention of carotenoids in tissues, Lophiosilurus alexandri juveniles were fed diets containing 0, 25, 50, 100, 200, and 400 mg/kg of synthetic astaxanthin for 62 days. The inclusion of astaxanthin did not result in significant differences in growth, weight gain, apparent feed conversion, and feed efficiency of the fish. Blood biochemistry and liver histology did not change with the different treatments. At the level of 100 mg/kg of inclusion, there were the highest levels of carotenoids in the blood, and muscle and the smallest difference between the muscle x integument ratio.

4.
Am J Otolaryngol ; 42(5): 103014, 2021.
Article in English | MEDLINE | ID: mdl-33873048

ABSTRACT

BACKGROUND: Smell dysfunction has been recognized as an early symptom of SARS-CoV-2 infection, often occurring before the onset of core symptoms of the respiratory tract, fever or muscle pain. In most cases, olfactory dysfunction is accompanied by reduced sense of taste, is partial (microsmia) and seems to normalize after several weeks, however, especially in cases of virus-induced complete smell loss (anosmia), there are indications of persisting deficits even 2 months after recovery from the acute disease, pointing towards the possibility of chronic or even permanent smell reduction for a significant part of the patient population. To date, we have no knowledge on the specificity of anosmia towards specific odorants or chemicals and about the longer-term timeline of its persistence or reversal. METHODS: In this longitudinal study, 70 participants from a community in Lower Austria that had been tested positive for either IgG or IgM SARS-CoV-2 titers in June 2020 and a healthy control cohort (N = 348) underwent smell testing with a 12-item Cross-Cultural Smell Identification Test (CC-SIT), based upon items from the University of Pennsylvania Smell Identification Test (UPSIT). The test was performed in October 2020, i.e. 4 months after initial diagnosis via antibody testing. Results were analyzed using statistical tests for contingency for each smell individually in order to detect whether reacquisition of smell is dependent on specific odorant types. RESULTS: For all odorants tested, except the odor "smoke", even 4 months or more after acute SARS-CoV-2 infection, participants with a positive antibody titer had a reduced sense of smell when compared to the control group. On average, while the control cohort detected a set of 12 different smells with 88.0% accuracy, the antibody-positive group detected 80.0% of tested odorants. A reduction of accuracy of detection by 9.1% in the antibody-positive cohort was detected. Recovery of the ability to smell was particularly delayed for three odorants: strawberry (encoded by the aldehyde ethylmethylphenylglycidate), lemon (encoded by citronellal, a monoterpenoid aldehyde), and soap (alkali metal salts of the fatty acids plus odorous additives) exhibit a sensitivity of detection of an infection with SARS-CoV-2 of 31.0%, 41.0% and 40.0%, respectively. CONCLUSION: Four months or more after acute infection, smell performance of SARS-CoV-2 positive patients with mild or no symptoms is not fully recovered, whereby the ability to detect certain odors (strawberry, lemon and soap) is particularly affected, suggesting the possibility that these sensitivity to these smells may not only be lagging behind but may be more permanently affected.


Subject(s)
COVID-19/complications , Odorants , Olfaction Disorders/epidemiology , Olfaction Disorders/virology , Adult , Austria , COVID-19/diagnosis , COVID-19/therapy , Case-Control Studies , Female , Humans , Longitudinal Studies , Male , Middle Aged , Olfaction Disorders/diagnosis , Recovery of Function , Symptom Assessment , Time Factors
5.
Unfallchirurg ; 123(9): 711-723, 2020 Sep.
Article in German | MEDLINE | ID: mdl-32140814

ABSTRACT

BACKGROUND: Prehospital resuscitative thoracotomy (PHRT) is a controversially discussed measure for the acute treatment of traumatic cardiac arrest (TCA) recommended by the current guidelines of the European Resuscitation Council (ERC). The aim of this work is the comprehensive presentation and summary of the available literature with the underlying hypothesis that the available publications show the feasibility and survival following PHRT in patients with TCA with a good neurological outcome. METHOD: A systematic literature search was performed in the databases PubMed, EMBASE, Google Scholar, Springer LINK and Cochrane. The study selection, data extraction and evaluation of bias potential were performed independently by two authors. The outcome of patients with TCA after PHRT was selected as the primary endpoint. RESULTS: A total of 4616 publications were found of which 21 publications with a total of 287 patients could be included in the analyses. For a detailed descriptive analysis, 15 publications with a total of 205 patients were suitable. The TCA of these patients was most commonly caused by pericardial tamponade, thoracic vascular injuries and severe extrathoracic multiple injuries. In 24% of the cases TCA occurred in the presence of the emergency physician. Clamshell thoracotomy (53%) was used preclinically more often than anterolateral thoracotomy (47%). Of the PHRT patients after TCA 12% (25/205) left the hospital alive, 9% (n = 19/205) with good neurological outcome and 1% (n = 3/205) with poor neurological outcome (according to the Glasgow outcome scale, GOS). CONCLUSION: The prognosis of TCA seems to be much better than has long been assumed. Decisive for the success of resuscitation efforts in TCA seems to be the immediate, partly invasive treatment of all reversible causes. The measures for TCA recommended by the ERC resuscitation guidelines, seem to be poorly implemented, especially in the preclinical setting. A controversy regarding the recommendations of the guidelines is the question of whether a PHRT can be successfully implemented and if the comprehensive introduction in Germany seems to be meaningful. Despite the recommendation of the guidelines, this systematic review and meta-analysis underlines the lack of high-quality evidence on PHRT, whereby a survival probability to hospital discharge of 12% was reported, of which 75% had a good neurological outcome. The risk of bias of the results in individual publications as well as in this review is high. Further systematic research in the field of preclinical trauma resuscitation is particularly necessary also for acceptance of the guidelines.


Subject(s)
Emergency Service, Hospital , Resuscitation , Thoracic Injuries , Thoracotomy , Germany , Humans , Mesothelin
6.
Arch Gynecol Obstet ; 299(2): 585-591, 2019 02.
Article in English | MEDLINE | ID: mdl-30607595

ABSTRACT

PURPOSE: Alterations in renal dimensions may be an early manifestation of deviation from normality, with possible repercussions beyond intrauterine life. The objective of this study was to establish reference curves for fetal kidney dimensions and volume from 14 to 40 weeks of gestation. METHODS: This is a prospective longitudinal study of 115 Brazilian participants in the "WHO multicentre study for the development of growth standards from fetal life to childhood: the fetal component". Pregnant women with clinical and sociodemographic characteristics allowing the full potential fetal growth were followed up from the first trimester until delivery. These women underwent serial sonographic evaluation of fetal kidneys. The longitudinal, anteroposterior and transverse diameters of both fetal kidneys were measured, in addition to calculation of kidney volume. By quantile regression analysis, reference curves of renal measurements related to gestational age were built. RESULTS: Standard normal sonographic values of renal biometry were defined during pregnancy. Reference values for the 10th, 50th and 90th centiles of different fetal kidney measurements (longitudinal, anteroposterior, transverse and volume) from the 14th to the 40th week of gestation were fitted. CONCLUSION: The reference curves presented should be of the utmost importance for screening and diagnosis of alterations in renal development during the intrauterine period.


Subject(s)
Fetal Development/physiology , Ultrasonography, Prenatal/methods , Adult , Child , Cohort Studies , Female , Humans , Longitudinal Studies , Pregnancy , Prospective Studies , Reference Values , Ultrasonography
7.
Molecules ; 24(19)2019 Sep 25.
Article in English | MEDLINE | ID: mdl-31557893

ABSTRACT

The Transitivity function, defined in terms of the reciprocal of the apparent activation energy, measures the propensity for a reaction to proceed and can provide a tool for implementing phenomenological kinetic models. Applications to systems which deviate from the Arrhenius law at low temperature encouraged the development of a user-friendly graphical interface for estimating the kinetic and thermodynamic parameters of physical and chemical processes. Here, we document the Transitivity code, written in Python, a free open-source code compatible with Windows, Linux and macOS platforms. Procedures are made available to evaluate the phenomenology of the temperature dependence of rate constants for processes from the Arrhenius and Transitivity plots. Reaction rate constants can be calculated by the traditional Transition-State Theory using a set of one-dimensional tunneling corrections (Bell (1935), Bell (1958), Skodje and Truhlar and, in particular, the deformed ( d -TST) approach). To account for the solvent effect on reaction rate constant, implementation is given of the Kramers and of Collins-Kimball formulations. An input file generator is provided to run various molecular dynamics approaches in CPMD code. Examples are worked out and made available for testing. The novelty of this code is its general scope and particular exploit of d -formulations to cope with non-Arrhenius behavior at low temperatures, a topic which is the focus of recent intense investigations. We expect that this code serves as a quick and practical tool for data documentation from electronic structure calculations: It presents a very intuitive graphical interface which we believe to provide an excellent working tool for researchers and as courseware to teach statistical thermodynamics, thermochemistry, kinetics, and related areas.


Subject(s)
Models, Chemical , Models, Theoretical , Algorithms , Kinetics
8.
Anaesthesist ; 68(Suppl 1): 15-24, 2019 02.
Article in English | MEDLINE | ID: mdl-28798972

ABSTRACT

BACKGROUND: Regarding survival and quality of life recent mass casualty incidents again emphasize the importance of early identification of the correct degree of injury/illness to enable prioritization of treatment amongst patients and their transportation to an appropriate hospital. The present study investigated existing triage algorithms in terms of sensitivity (SE) and specificity (SP) as well as its process duration in a relevant emergency patient cohort. METHODS: In this study 500 consecutive air rescue missions were evaluated by means of standardized patient records. Classification of patients was accomplished by 19 emergency physicians. Every case was independently classified by at least 3 physicians without considering any triage algorithm. Existing triage algorithms Primary Ranking for Initial Orientation in Emergency Medical Services (PRIOR), modified Simple Triage and Rapid Treatment (mSTaRT), Field Triage Score (FTS), Amberg-Schwandorf Algorithm for Triage (ASAV), Simple Triage and Rapid Treatment (STaRT), Care Flight, and Triage Sieve were additionally carried out computer based on each case, to enable calculation of quality criteria. RESULTS: The analyzed cohort had an age of (mean ± SD) 59 ± 25 years, a NACA score of 3.5 ± 1.1 and consisted of 57% men. On arrival 8 patients were deceased. Consequently, 492 patients were included in the analysis. The distribution of triage categories T1/T2/T3 were 10%/47%/43%, respectively. The highest diagnostic quality was achieved with START, mSTaRT, and ASAV yielding a SE of 78% and a SP ranging from 80-83%. The subgroup of surgical patients reached a SE of 95% and a SP between 85-91%. The newly established algorithm PRIOR exerted a SE of 90% but merely a SP of 54% in the overall cohort thereby consuming the longest time for overall decision. CONCLUSION: Triage procedures with acceptable diagnostic quality exist to identify the most severely injured. Due to its high rate of false positive results (over-triage) the recently developed PRIOR algorithm will cause overload of available resources for the severely injured within mass casualty incident missions. Non-surgical patients still are poorly identified by the available algorithms.


Subject(s)
Algorithms , Mass Casualty Incidents/statistics & numerical data , Triage/methods , Adult , Aged , Aged, 80 and over , Cohort Studies , Disaster Planning/methods , Emergency Medical Services , Emergency Service, Hospital , Female , Humans , Male , Middle Aged , Physicians , Quality of Life
9.
Unfallchirurg ; 122(5): 381-386, 2019 May.
Article in German | MEDLINE | ID: mdl-30789998

ABSTRACT

A mass casualty event (MCE) poses an enormous challenge for rescue services and hospitals. In addition to a hospital emergency plan, employee training and practice exercises are essential to be prepared for such an event. The organizational and financial burden of MCE exercises in a hospital is extraordinarily high. In a retrospective analysis of several large hospital exercises, the magnitude of the necessary financial means for the preparation and execution of such drills is outlined. Depending on the size (number of patients) and scope (extent of departments involved) of the MCE exercise in a hospital, a full-size MCE drill may entail costs between 10,000 and 100,000€. Since the execution of such exercises is essential in the sense of preparedness and considering quality management aspects, possibilities of refinancing and more cost-efficient training must be developed.


Subject(s)
Disaster Planning , Mass Casualty Incidents , Emergency Service, Hospital , Exercise Therapy , Hospitals , Humans , Retrospective Studies
10.
Unfallchirurg ; 122(4): 299-308, 2019 Apr.
Article in German | MEDLINE | ID: mdl-30178110

ABSTRACT

BACKGROUND: The incidence and character of civil mass casualty incidents (MCI) has changed in the last decades, in particular because of the rising number of terrorist attacks. As a result, the question arises whether commonly used tools of prevention and prehospital planning, including the distribution of triage categories (T1 severely injured/T2 seriously injured/T3 slightly injured) with 15%/20%/60% have to be modified. The rescue workers make the classification of the triage categories in MCIs at the scene. The aim of this article is to verify the planning size of variable distribution of the triage categories. MATERIAL AND METHODS: A total of 244 MCI with >9 casualties from 1 January 1985 to 31 May 2017 in Europe and Turkey were identified by a systematic literature search and analyzed with respect to the distribution of T in the first 24 h. RESULTS: An incidence of 10% T1, 17% T2, 49% T3 and 5% deaths was detected (median). Due to the previously use of the average of the triage categories in the contingency plan, the calculation showed a slightly different distribution from 15%/30%/55%. Of the events 7 were natural disasters, 227 terrorist attacks, 9 accidents and 1 mass panic. Natural disasters showed a higher than average death rate (11%), especially landslide incidents (67%). Civilian accidents showed a distribution of T of 10%/17%/55%, with train derailments having twice as many T1 patients and plane crashes just under twice as many T2 patients. In the case of terrorist attacks, the expected planning parameters were not quite achieved with 14%/15%/39%. Especially "combined hits" and amok driving had high incidences of T1 patients (18% and 21%, respectively). In addition, the T2 patients with 42% in amok driving and 48% in mass panics were well above the planning size of 20% and 30%, respectively. Calculation of the severity factor according to deBoer for amok driving and the result that at S ≥ 1.5 many seriously injured persons can be suspected, amok driving showed the highest degree of severity (S = 1.8) in our study. This indicates the severity of a disaster depending on the number of casualties per triage category.


Subject(s)
Disaster Planning , Mass Casualty Incidents , Triage/classification , Disaster Planning/methods , Europe , Humans , Terrorism
11.
J Comput Chem ; 38(3): 178-188, 2017 01 30.
Article in English | MEDLINE | ID: mdl-27859380

ABSTRACT

A formulation is presented for the application of tools from quantum chemistry and transition-state theory to phenomenologically cover cases where reaction rates deviate from Arrhenius law at low temperatures. A parameter d is introduced to describe the deviation for the systems from reaching the thermodynamic limit and is identified as the linearizing coefficient in the dependence of the inverse activation energy with inverse temperature. Its physical meaning is given and when deviation can be ascribed to quantum mechanical tunneling its value is calculated explicitly. Here, a new derivation is given of the previously established relationship of the parameter d with features of the barrier in the potential energy surface. The proposed variant of transition state theory permits comparison with experiments and tests against alternative formulations. Prescriptions are provided and implemented to three hydrogen transfer reactions: CH4 + OH → CH3 + H2 O, CH3 Cl + OH → CH2 Cl + H2 O and H2 + CN → H + HCN, widely investigated both experimentally and theoretically. © 2016 Wiley Periodicals, Inc.


Subject(s)
Hydrogen/chemistry , Quantum Theory , Thermodynamics
12.
Anaesthesist ; 66(10): 762-772, 2017 Oct.
Article in German | MEDLINE | ID: mdl-28710612

ABSTRACT

BACKGROUND: Regarding survival and quality of life, recent mass casualty incidents have once more emphasized the importance of early identification of the correct degree of injury or illness, to enable prioritizing treatment of patients and transportation to an appropriate hospital. The present study investigated international triage algorithms in terms of sensitivity (SE) and specificity (SP) as well as the process duration in a relevant emergency patient cohort. METHODS: A total of 500 consecutive air rescue missions were evaluated by means of standardized patient records. Interdisciplinary classification of patients was accomplished by 19 emergency physicians. Every case was independently classified according to the triage category by at least three physicians without considering any triage algorithm. The available triage algorithms PRIOR (Primary Ranking for Initial Orientation in Emergency Medical Services), mSTaRT (modified Simple Triage and Rapid Treatment), FTS (Field Triage Score), ASAV (Amberg-Schwandorf Algorithm for Triage), STaRT (Simple Triage and Rapid Treatment), CareFlight triage and Triage Sieve were additionally carried out for each patient in a computer-based procedure, to enable calculation of test quality criteria for all procedures. RESULTS: The analyzed cohort had a mean age of 59 ± 25 years (±SD), a National Advisory Committee for Aeronautics (NACA) score of 3.5 ± 1.1 and consisted of 57% men. On arrival 8 patients were already deceased, consequently 492 patients were included in the analysis. The distributions of triage categories I/II/III were 10%/47%/43%, respectively. The highest diagnostic quality was achieved with START, mSTaRT, and ASAV with 78% SE and 80-83% SP. The subgroup of surgical patients achieved 95% SE and 85-91% SP. The newly established algorithm PRIOR exerted an SE of 90% but an SP of only 54% in the overall cohort thereby taking the longest overall time for decisions. CONCLUSION: Triage procedures with acceptable diagnostic quality exist to identify the most severely injured. Due to its high rate of false positive results (overtriage) in this study, the recently developed PRIOR algorithm could result in exhaustion of available resources for the severely injured and therefore to undertreatment of correctly assigned triage category I cases within mass casualty incidents. Non-surgical patients are still poorly allocated by the available algorithms. Contribution available free of charge by "Free Access".


Subject(s)
Algorithms , Mass Casualty Incidents/statistics & numerical data , Triage/methods , Adult , Aged , Aged, 80 and over , Civil Defense , Clinical Decision-Making , Cohort Studies , Disaster Planning , Emergency Medical Services , Female , Humans , Male , Middle Aged , Physicians , Predictive Value of Tests , Reproducibility of Results , Rescue Work , Triage/statistics & numerical data
13.
Anaesthesist ; 66(12): 924-935, 2017 Dec.
Article in German | MEDLINE | ID: mdl-29143074

ABSTRACT

INTRODUCTION: More than half of all traumatic deaths happen in prehospital settings. Until now, there have been no long-term studies examining the actual additive treatment during trauma-associated cardiopulmonary resuscitation (tCPR), including pleural decompression, pericardiocentesis, tourniquets and external stabilization of the pelvis. The present cohort study evaluated forensic autopsy reports of trauma deaths occurring at the scene with respect to additive actions in preclinical tCPR as well as the potentially preventable nature of the individual death cases. MATERIAL AND METHODS: All autopsy protocols from the Institutes of Legal Medicine in Leipzig and Chemnitz, Germany within the years 2011-2017 were retrospectively examined and all trauma deaths with professional prehospital tCPR at the scene, during transport or shortly after arriving at the emergency room were analyzed. In addition to epidemiological parameters all forms of medical procedure performed by emergency physicians and the injury patterns were recorded. Thus, the questions whether any of the trauma deaths were preventable and if failures in work-flow management were evident could be retrospectively answered through a structured Delphi method. RESULTS: Overall, 3795 autopsy protocols were listed containing 154 trauma cases (4.1%) with various preclinical tCPR attempts (male patients 70.1%; mean age 48 ± 21 years). Most of them died at the accident site (84.4%), some during transport (2.6%) or directly after admission to a hospital (13.0%). Only 23 patients (14.9%) received 25 additional interventions exceeding the normal scope (pleural decompression 80.0%, pericardiocentesis 8.0% and external stabilization of the pelvis 12.0%). A relevant number of potentially reversible causes for trauma-associated cardiac arrest was determined. There were deficits in the performance of pleural decompression in cases of tension pneumothorax. Even if isolated traumatic hemopericardium was a rare occurrence in the examined cases, the rate of pericardiocentesis was still too low. Also, more focus needs to be placed on provisional external pelvic stabilization of trauma patients which was performed too rarely even though an instable pelvic ring was apparent during the postmortem external examination. None of the cases received a rescue thoracotomy even if a few patients might have derived benefit from this and none of the cases showed injury patterns with tourniquet indications. Furthermore, no single case of death due to incorrect or missing airway management was determined. Errors in work-flow management were found in 37.0% and potentially preventable deaths occurred cumulatively in 12.3% of the cases. The potentially preventable deaths were particularly related to penetrating chest injuries caused by a sharp force. DISCUSSION: The percentage of patients who might benefit from additive treatment implemented in tCPR efforts was shown to be equal between the local situations in Leipzig and Chemnitz compared to previous reports in Berlin. A need for optimizing the professional resuscitation process still remains as not all reversible causes were appropriately addressed. Further training and education should intensively address the mentioned deficits and continuous awareness of necessary additional medical procedures in the preclinical setting in cases of traumatic cardiac arrest is inevitable. Cooperation with forensic institutes can help to impart particular issues and treatment options of emergency medicine in cases of potentially reversible causes of traumatic cardiac arrest.


Subject(s)
Heart Arrest/etiology , Heart Arrest/therapy , Wounds and Injuries/complications , Wounds and Injuries/therapy , Adult , Aged , Airway Management , Autopsy , Cardiopulmonary Resuscitation , Cause of Death , Cohort Studies , Emergency Medical Services , Female , Humans , Male , Middle Aged , Pneumothorax/etiology , Pneumothorax/therapy , Retrospective Studies , Thoracic Injuries/complications , Thoracic Injuries/therapy
14.
J Phys Chem A ; 120(27): 5408-17, 2016 Jul 14.
Article in English | MEDLINE | ID: mdl-27205872

ABSTRACT

Among four-atom processes, the reaction OH + HBr → H2O + Br is one of the most studied experimentally: its kinetics has manifested an unusual anti-Arrhenius behavior, namely, a marked decrease of the rate constant as the temperature increases, which has intrigued theoreticians for a long time. Recently, salient features of the potential energy surface have been characterized and most kinetic aspects can be considered as satisfactorily reproduced by classical trajectory simulations. Motivation of the work reported in this paper is the investigation of the stereodirectional dynamics of this reaction as the prominent reason for the peculiar kinetics: we started in a previous Letter ( J. Phys. Chem. Lett. 2015 , 6 , 1553 - 1558 ) a first-principles Born-Oppenheimer "canonical" molecular dynamics approach. Trajectories are step-by-step generated on a potential energy surface quantum mechanically calculated on-the-fly and are thermostatically equilibrated to correspond to a specific temperature. Here, refinements of the method permitted a major increase of the number of trajectories and the consideration of four temperatures -50, +200, +350, and +500 K, for which the sampling of initial conditions allowed us to characterize the stereodynamical effect. The role is documented of the adjustment of the reactants' mutual orientation to encounter the entrance into the "cone of acceptance" for reactivity. The aperture angle of this cone is dictated by a range of directions of approach compatible with the formation of the specific HOH angle of the product water molecule; and consistently the adjustment is progressively less effective the higher the kinetic energy. Qualitatively, this emerging picture corroborates experiments on this reaction, involving collisions of aligned and oriented molecular beams, and covering a range of energies higher than the thermal ones. The extraction of thermal rate constants from this molecular dynamics approach is discussed and the systematic sampling of the canonical ensemble is indicated as needed for quantitative comparison with the kinetic experiments.

15.
Anaesthesist ; 65(8): 601-8, 2016 Aug.
Article in German | MEDLINE | ID: mdl-27358076

ABSTRACT

There are considerable similarities and intersections between forensic medicine and emergency medicine. This applies especially to frustraneously resuscitated patients or other lethal clinical courses of traumatized patients who are subject to latter forensic autopsy. Cooperation between departments of emergency and forensic medicine not only has emergency medical training potential, but also the possibility of retrospective evaluation of medical emergency measures - both in individual cases and with regard to epidemiological aspects. In particular, the widespread registration of autopsied pre-hospital trauma deaths that occurred despite on-scene resuscitation attempts is useful. The pre-hospital situation represents a hotspot, but also a blind spot in the overall trauma mortality. In recent clinical registers, preclinical deaths go mostly unrecorded, despite the undisputed benefits of clinical registers.


Subject(s)
Emergency Medicine , Forensic Medicine , Autopsy , Cause of Death , Emergency Medicine/education , Germany , Humans , Resuscitation , Wounds and Injuries/mortality , Wounds and Injuries/therapy
16.
Phys Chem Chem Phys ; 17(11): 7443-8, 2015 Mar 21.
Article in English | MEDLINE | ID: mdl-25704594

ABSTRACT

Recent studies have reported surprising results related to the rearrangement of carbenes under ultracold conditions, making use of sophisticated models of quantum tunnelling to explain the observed phenomena. Here, we demonstrate that a methylhydroxycarbene (H3C-C-OH) rearrangement is possible by making changes in molecularity (i.e., through cooperative effects), owing to intermolecular hydrogen bond/H-transfer. The model used for accomplishing these changes in molecularity suggests the occurrence of two chemical species during the rearrangement and preferential formation of acetaldehyde. We propose an alternative interpretation for the methylhydroxycarbene rearrangement, as well as for a bimolecular isomerization mechanism for acetaldehyde formation with an activation barrier, Ea, of +0.25 kcal mol(-1), relative to 1a' (−8.06 kcal mol(-1) relative to 1a); this barrier is lower than that required by H-tunnelling as proposed by Schreiner et al. We also note that the mechanism for obtaining vinyl alcohol leads to the simultaneous formation of acetaldehyde through an Ea of +13.53 kcal mol(-1), relative to 1a (+0.93 kcal mol(-1) relative to 1b), again confirming the predominant presence of acetaldehyde.

17.
An Acad Bras Cienc ; 87(1): 529-35, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25806995

ABSTRACT

In aquaculture, activities with anesthetic compounds are usually used in order to ensure the welfare of farmed fish, allowing handling out of water with decreased trauma by stress. Presently, there is no information about anesthetic action of eugenol in early life stages of Nile tilapia (Oreochromis niloticus). The objective of this study was to evaluate different concentrations of eugenol for larvae and juveniles of Nile tilapia. Sixty animals were used for each group of weight, group I = 0.02 g; group II = 0.08 g; group III = 0.22 g; group IV = 2.62 g; and group V = 11.64 g. The eugenol concentrations tested were 50, 75, 100, 125, 150 and 175 mg L-1. No mortality was reported during the tests with eugenol. Tilapia larvae with 0.02 g and juveniles around 11.64 g can be anesthetized with eugenol concentrations between 150 and 175 mg L-1, since they determine the shortest sedation time (23 and 72 seconds, for the group of lowest and highest weights, respectively).


Subject(s)
Anesthetics/administration & dosage , Aquaculture/methods , Cichlids , Eugenol/administration & dosage , Animals , Dose-Response Relationship, Drug , Larva , Time Factors
18.
Anaesthesist ; 64(7): 520-6, 2015 Jul.
Article in German | MEDLINE | ID: mdl-26036317

ABSTRACT

Tension pneumothorax can occur at any time during cardiopulmonary resuscitation (CPR) with external cardiac massage and invasive ventilation either from primary or iatrogenic rib fractures with concomitant pleural or parenchymal injury. Airway injury can also cause tension pneumothorax during CPR. This article presents the case of a 41-year-old woman who suffered cardiopulmonary arrest after undergoing elective mandibular surgery. During CPR the upper airway could not be secured by orotracheal intubation due to massive craniofacial soft tissue swelling. A surgical airway was established with obviously unrecognized iatrogenic tracheal perforation and subsequent development of tension pneumomediastinum and tension pneumothorax during ventilation. Neither the tension pneumomediastinum nor the tension pneumothorax were decompressed and accordingly resuscitation efforts remained unsuccessful. This case illustrates the need for a structured approach to resuscitate patients with ventilation problems regarding decompression of tension pneumomediastinum and/or tension pneumothorax during CPR.


Subject(s)
Cardiopulmonary Resuscitation/adverse effects , Mediastinal Emphysema/etiology , Mediastinal Emphysema/therapy , Pneumothorax/etiology , Pneumothorax/therapy , Trachea/injuries , Adult , Airway Management , Fatal Outcome , Female , Heart Arrest/complications , Heart Arrest/therapy , Heart Massage , Humans , Iatrogenic Disease , Intubation, Intratracheal , Mandible/surgery
19.
Orthopade ; 43(1): 70-8, 2014 Jan.
Article in German | MEDLINE | ID: mdl-24414232

ABSTRACT

BACKGROUND: Periprosthetic infections (PPI) represent one of the most complex complications in arthroplasty concerning both, diagnosis and therapy. The incidence of PPI of the hip is approximately 1 % after primary procedures and 4 % after revision surgery. About two thirds of PPIs occur via intraoperative contamination and the remaining PPIs are acquired by hematogenous seeding. AIM: This article presents an overview of up to date evidence-based diagnostics and therapy of PPI of the hip with the establishment of a clear algorithm. METHODS: A selective literature search was carried out with the inclusion of own work. RESULTS: A PPI must be actively excluded in cases of a painful prosthesis or signs of loosening within the first years after implantation. Measurement of C-reactive protein (CRP) can be normal especially in cases of chronic (low grade) PPI and cannot be used as an exclusion criterion. The standard diagnostic procedure includes preoperative joint aspiration with culture and leukocyte counts as well as culture and histology of periprosthetic tissue. Imaging techniques, such as magnetic resonance imaging (MRI) and scintigraphy are of inferior significance. Newer methods, such as sonication of removed implants have revolutionized the diagnostics and several cases which had previously been considered aseptic loosening failures have now been reclassified as PPI. Essential parameters for the treatment algorithm are maturity of the biofilm, stability of the prosthesis, the causative organism and the state of the soft tissue. Retention of the prosthesis can only be considered when the biofilm is still immature (acute PPI). In chronic (low grade) PPI eradication of the infection can only be achieved by exchanging the prosthesis. This has to be performed either as a one-stage procedure or as a two-stage exchange with a short (2-4 weeks) or a long (> 6 weeks) interval. Biofilm active antibiotics play an essential role in the treatment of PPI and have to be used as targeted therapy. DISCUSSION: Successful therapy and diagnostics of PPI require following an exact algorithm. The interdisciplinary cooperation between specialists for infectious diseases and microbiologists represents a decisive factor.


Subject(s)
Algorithms , Anti-Bacterial Agents/therapeutic use , Arthroplasty, Replacement, Hip/adverse effects , Prosthesis-Related Infections/diagnosis , Prosthesis-Related Infections/therapy , Humans , Prosthesis-Related Infections/etiology
20.
Chirurgie (Heidelb) ; 2024 Sep 06.
Article in German | MEDLINE | ID: mdl-39242447

ABSTRACT

At the latest since the Medical Services Healthcare Insurance Reform Act (MDK), the declared will of the legislation is the conversion of operations previously carried out in an inpatient setting to an outpatient setting. In trauma surgery and orthopedics numerous operations are carried out that could principally also be performed in an outpatient setting; however, a prerequisite is a medical assessment of the suitability of patients as well as an economic and normative framework that makes outpatient surgery attractive. Both the Outpatient Surgery in Hospitals Catalogue (AOP-Katalog) and the first edition of the Hybrid Diagnosis-related Groups (DRG) define interventions in trauma surgery that could be carried out in an outpatient setting. Hospitals are therefore required to find solutions for these interventions under processual and economic provisos. These range from omission of outpatient operations to the expansion as a separate financial department in the hospital. With the introduction of the hybrid DRG, the legislation enables equal remuneration for outpatient versus short-term inpatient treatment and leaves the case management up to the hospital; however, the performance of the AOP in the setting of a hospital and also hybrid case flat rates are as a rule not economically viable and bear the risk of the failure of all efforts at conversion to outpatient settings. It is necessary to carry out a fundamental revision of the remuneration and framework conditions for outpatient operations in trauma surgery and orthopedics in hospitals, involving practitioners. This is the only way that the conversion to outpatient treatment can succeed.

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