Multiple soft-mode vibrations of lead zirconate.

Polarized Raman, IR, and time-domain THz spectroscopy of orthorhombic lead zirconate single crystals have yielded a comprehensive picture of temperature-dependent quasiharmonic frequencies of its low-frequency phonon modes. It is argued that these modes primarily involve vibrations of Pb ions and librations of oxygen octahedra. Their relation to phonon modes of the parent cubic phase is proposed. Counts of the observed IR and Raman active modes belonging to distinct irreducible representations agree quite well with group-theory predictions. Analysis of the results yields insight into the phase transition mechanism, involving a soft ferroelectric branch coupled by a trilinear term to another two oxygen octahedra tilt modes.

Ferroelastic structures of n-pentyl-, n- hexyl- and n-nonylammonium dihydrogenphosphate crystals.

This study reports the structure redeterminations of C(5)H(11)NH(3)(+).H(2)PO(4)(-) (n-pentylammonium dihydrogenphosphate, C5ADP), C(6)H(13)NH(3)(+).H(2)PO(4)(-) (n-hexylammonium dihydrogenphosphate, C6ADP) and C(9)H(19)NH(3)(+).H(2)PO(4)(-) (n-nonylammonium dihydrogenphosphate, C9ADP). The structures are monoclinic (P2(1)/n), belonging to the series of previously studied structures C2ADP-C8ADP and C10ADP. The structures exhibit reproducible ferroelastic switching. There are hydrogen bonds between the dihydrogenphosphates and the n-alkylammonium groups. Among them there are two hydrogen bonds with hydrogens which hop from the donor to the acceptor oxygens during the ferroelastic switching. C5ADP as well as C3ADP differ from the other members of the series by packing of the double layers of the dihydrogenphosphates. Moreover, the packing of n-alkylammonium molecules in all these structures depends on the parity of the number of atoms in the n-alkylammonium chains. All the samples contained two domains and their structures were refined as twins.

[Fundamentals of comprehensive prevention of the post-traumatic fat embolism syndrome]. / Základy komplexní profylaxe syndromu posttraumatické tukové embolie.

Urgent top standard provisions implemented as soon as possible after serious injuries with the aim to prevent the development of shock or treat incipient and developing shock are among the most important aspects of prophylaxis of the traumatic fat embolism syndrome (FE). These provisions comprise quantitative and qualitative replacement of blood losses, prevention of spasms of the peripheral blood vessels, restoration of the microcirculation, maintenance of the acid-base equilibrium and a normal state of coagulation, normalization of fluctuations of the post-traumatic metabolic and humoral response, blocking of pathological impulses from the site of the fracture incl. settling of the long bones; suppression of hypoxia, in particular also by artificial pulmonary ventilation; a high caloric intake to prevent excessive development of lipolysis. Surgical operations with the exception of urgent ones which form part of urgent intensive care must be postponed to the time when clinical manifestations of traumatic shock have completely subsided. The group of comprehensive prophylactic provisions comprises also pharmacological measures/drugs and substances which influence the pathogenetic basis associated with the genesis and development of the FE syndrome and the more general syndrome of post-traumatic dyslipidaemic coagulopathy resp.

[The role of pharmacology in the comprehensive prophylaxis of post-traumatic fat embolism]. / Farmakologický podíl na komplexní profylaxi syndromu poúrazové tukové embolie (TE).

Immediate high-standard provisions implemented as soon as possible after serious injuries with the aim to prevent the development of shock or to treat incipient and developing shock is one of the most important aspects of prophylaxis of the syndrome of traumatic fat embolism (FE). An important place is held by the rostoration of normal microcirculation, replacement of blood losses and the control of hypoxia, in particular by artificial pulmonary ventilation. A high caloric intake both by the parenteral and enteral route has among others the objective to prevent excessive development of lipolysis. Surgical operations with the exception of urgent ones which must not be delayed should be postponed till complete regression of clinical manifestations of traumatic shock. The group of comprehensive provisions comprises pharmacological provisions against traumatic shock and pharmacological participation in the prophylaxis of the FE syndrome: Lipostabil; Trasylol; heparin and other anticoagulants in small doses; hydrocortisone; dextrans, CaCl2 and possibly other effective substances or drugs in rational individually recommended doses and expedient combinations.

[Possibilities of determining prognosis in the transformation of post-traumatic dyslipidemic coagulopathy into the clinical fat embolism syndrome]. / Moznost stanovení prognózy prechodu posttraumatické dyslipidemické koagulopatie do klinického syndromu tukové embolie.

The clinical and laboratory retrospective and prospective study orientated to the observation of total posttraumatic response of the organisms to serious injuries (fractures of long bones of lower extremities, fractures of bones of pelvis, serious multiple injuries of body cavities associated with fractures) has concentrated hyperglobulaemia and at the same time also of disorders of blood coagulation. These in all three institutes on the verification of the significance of hyperglobulaemia, disorders of blood coagulation and persistent tachycardia. The analysis of the relations between the findings of fat hyperglobulaemia, disorders of coagulation and persistent tachycardia has made it possible to present a thesis which is very important from the practical viewpoint, and namely that the persistent tachycardia in case of in-patients is in fact a clinical reflection or manifestation, an equivalent, even of the incidence of fat studies concentrated on the syndrome of traumatic fat embolism (F. E.) were carried out within a uniform concept of "post-traumatic dyslipidemic coagulopathy - PDC". A statistically significant relation has been proved between the incidence of fat hyperglobulaemia and the incidence of persistent tachycardia. When identifying the relations between individual laboratory and clinical findings the authors have proceeded from a pre-requisite we have objectified before, and namely that fat hyperglobulaemia and disorders in blood coagulation contribute significantly to the development of the syndrome of post-traumatic fat embolism. The origin of persistent tachycardia which is motivated in patients with fractures of bones neither by the increase of temperature nor by any other pathophysiological circumstances, represents a turning point or a time limit between PDC as a latent pathological condition and PDC with clinical manifestations, being associated in the subclinical form only with persistent tachycardia or in the manifest form with other evident symptoms (including persistent tachycardia). It is then possible to use the symptom of an early and persistent tachycardia in the clinical practice for the prognostication of possibilities of unfavourable pathophysiological development of the subclinical form of fat embolism into the clinically manifest form of fat embolism.

[Definition of "polytrauma" and "polytraumatism"]. / K definici polytraumatu a polytraumatismu.

Polytrauma (multitrauma) is a short verbal equivalent used for severely injured patients usually with associated injury (i.e. two or more severe injuries in at least two areas of the body), less often with a multiple injury (i.e. two or more severe injuries in one body area). An important condition for the use of the term polytrauma is the incidence of the traumatic shock and/or hemorrhagic hypotensis and a serious endangering of one or more vital functions of the organism. At least one out of two or more injuries or the sum total of all injuries endangers the life of the injured person with polytrauma. For its variable and non-homogeneous content the term polytrauma cannot be used as a final diagnosis without an objective quantification of the extent of the severity of the injury. The author therefore recommends to use this term to express a severe injury endangering the life as a general term which must be necessarily specified by the actual morphological and functional diagnoses. The term "polytraumatism" used in practice is not exactly a synonym of polytrauma, however, it has a direct generalizing relation to it. Polytraumatism embraces the broad health care and general societal problem area relating to severe associated and multiple injuries (i.e. to polytrauma). The author presents the actual classification of polytraumas according to their severity into four, three or two groups. This classification is based on the principles of general quantification of the severity of the injury (from the viewpoint of individual injuries and at the same time from the viewpoint of all concurrent injuries) divided into five or six grades.

Early complications in patients with multiple injuries and polytraumatism with special regard to traumatic fat embolism.

In the introductory part contemporary data concerning fat embolism occurrence and mortality, as taken from the world literature, are evaluated. Thus, the author opens the whole complicated problem of post-mortem examination findings with a different extent of fat embolization (most often in the lungs, rarely in organs belonging to the area supplied by the systemic blood circulation) on the one hand and the fat embolism clinical syndrome on the other hand. The clinical syndrome is a rare phenomenon in comparison with the relatively frequent morphological abduction findings of a more serious character (of the 2nd and higher degree). The evaluation of fat embolism as the main cause of death cannot be based only on the morphological findings, ascertained at the post-mortem examination in the organs of patients who died of injury consequences. At the same time, however, the question is open of evaluating the fat embolism syndrome as the contrary of the fulminant form of fat embolism to the classical fat embolism syndrome as it manifests itself in practice after the free interval. The author sees the mentioned contrary in the fact that the diagnosis of the fulminant fat embolism syndrome resulting in death within a few hours is mainly based on the microscopical findings of fat embolism in the capillaries of the organs whereas that of the classical fat embolism syndrome is possible not only clinically but can be confirmed also macroscopically and microscopically, morphologically and histologically in the cases of death of such injured patients. The morphological confirmation of the classical fat embolism syndrome after an accidental death within some weeks after the injury and after the clinical course of the classical syndrome has, however, time limits as far as the macroscopical findings but especially the microscopical evidence of fat embolism are concerned. In this part of the study many statements of the author are based on the occurrence of 208 patients with fat embolism in the continuously observed clinical material of all the hospitalized injured persons (16,706) at the Research Institute of Traumatology between 1963-1983. In consideration of the accumulated admission of severely injured patients from traffic accidents especially, the total mortality is 6.55% (6.25% of men; 7.18% of women). Fat embolism as the main cause of death makes up 10.15% (8.25% of men; 13.61% of women) of total mortality. The occurrence of the fat embolism syndrome is, however, much lower: 1.25% (1.16% of men; 1.43% of women). The fat embolism syndrome mortality is high: 53.73% (44.70% of men; 68.42% of women).

Fat globulemia in early diagnostics of traumatic fat embolism.

In our opinion, this clinical study demonstrates the intravascular formation of globules, macroglobules and their aggregations both in the association with the type of general anaesthesia and with the operative osteosynthesis of long bones. Within the framework of this study changes in the level of lactic acid in blood serum and of total ketosubstances in blood were followed as well as the levels of total lipids, triglycerides, phospholipides, serum lipase, non-esterified and esterified fatty acids, changes in blood coagulation and 17-ketosteroides in blood. The observed changes supported the opinion that the development of fat globulemia was associated with humoral and physicochemical changes in blood. Repeated evaluations of fat globulemia in plasma are important for studies on pathogenesis and development of fat embolism. In practice, they help: to diagnose especially subclinical forms of fat embolism with non-marked clinical symptoms; to define a suitable term of both primary and delayed operation performed in the period of ending katabolic phase after severe trauma; to define an optimum time for the indication of osteosynthesis to the end of manifest fat embolism; to control positive effects of drugs used for the prophylaction and treatment of fat embolism. In this way it is possible to objective the effectiveness of a rational prophylaxis and treatment of fat embolism. Following factors contribute to macroglobulamia and to manifestation of F. E.: injuries to bones, tissues and organs; stress, posttraumatic shock; severe hemorrhagic hypotension; posttraumatic hypercoagulation with possible binding to the development of a consumption coagulopathy; heavy changes of acid-base balance; increase of catecholamines in plasma; hormonal and general metabolic disturbances; posttraumatic dyslipidemia with special regard to the decrease of beta-lipoproteins and of lipoproteinlipase activity together with the increase of lipoproteins having a very low density and with the occurrence of a significant lipoprotein coalescence. The prospective study on the globulemia changes is based on the following examinations: in 76 injured patients: a short time observation (24 hours) of the globulemia changer after osteosyntheses in general anesthesia. The operative interventions were usually performed 6 to 8 days after injury. in 60 injured patients with fractures (single or multiple fractures, fractures in polytrauma patients): a long-time observation (28 days) of the globulemia changes.

Indications of primary osteosynthesis in patients with fractures of long bones of extremities with special regard to multiple and associated fractures of femur diaphysis.

Fractures of the long shaft-shaped bones were evaluated upto the sixties as an isolated therapeutic problem. During the past fifteen years, however, views as regards treatment of fractures of long bones began to change along with the increasing number of multiple fractures and polytraumas. It was revealed that fractures of the long bones and pelvic fractures have a bearing on the development of the syndrome of fat embolism, the syndrome of acute respiratory distress in adults, on the development of shock damage of the lungs, heart, kidneys, liver, pancreas etc. Evidence was accumulating that unstable fractures of the long shaft-shaped bones contribute towards the development of these complications. During the past ten years stable osteosynthesis of fractures of the long bones, in particular of the lower extremities, has gained priority among operations which have a positive effect on the stabilization of the organism in the early postinjury stage of polytrauma. Modern traumatology solves the dilemma which developed in practice from the need of early osteosynthesis on the one hand and reflections on possible deterioration of the general condition of the organism of the severely injured as a result of urgent or early osteosynthesis, on the other hand. Modern traumatology seeks a basis for objective assessment of conditions and parameters for possible primary or early delayed osteosynthesis in multiple injuries with the aim to shift the indication for stable osteosynthesis of fractures of the femur in multiple injuries to the onset of the stabilization phase.