Biomedical subjects

U Lehmann

Publications and source records attributed to U Lehmann.

At least 55 records · Page 3Linked to original sources

PubMed1997

[Initial cranial CT for evaluating the prognosis of craniocerebral trauma].

A total of 208 multiple trauma patients with head injury (HI) were investigated who had been treated in the period from 1990 to 1995. The average age was 35.2 +/- 17.7 years; the injury severity according to ISS was 30.2 +/- 8.6 points; 20.5% died as a result of the HI; the mortality of all patients was 26.5%. The Glasgow Coma Scale (GCS) was determined at an average of 22 min after trauma (8.0 +/- 4.3 points) at the scene of accident. The patients were classified according to GCS into minor HI (group 1: 14-15 points), moderate HI (group 2: 9-13 points) and severe HI (group 3: 3-8 points). Patient outcome was assessed by the Glasgow Outcome Scale (GOS) and was classified as good (GOS 4 and 5) and poor (GOS 1, 2 and 3) outcome. At the latest, 2 h after trauma, a CT scan of the head (CCT) was done. The HI groups are compared regarding frequency of types of injury. In all HI groups the fractures of the bony face occurred at the same frequency (36.0-38.9%). The frequency of calotte fractures (Kal-Fx) increased from group 1 (8.0%) to 2 (19.2%) and 3 (25.6%); fractures of the skull base significantly differed between group 1 (16.0%), 2 (7.8%) and 3 (33.4%). Epidural hemorrhage (EDB) appeared only in group 2 (7.8%) and 3 (6.7); subdural hemorrhage was found in group 1 (2.7%), 2 (7.8%) and 3 (10.0%). Subarachnoid hemorrhage (SAB) was significantly more frequently seen, dependent on HI severity, in group 3 (26.7%) compared to group 2 (11.7%) and 1 (8.0%). Intracerebral contusion (ICK) significantly increased from group 1 (12.0%) to 2 (27.3) and 3 (45.6%). Brain swelling (BS) also significantly increased from group 1 (8.0%) to 2 (19.5%) and 3 (49.0%) and lesions of ventricles (VL) from group 1 (2.7%) to 2 (11.7%) and 3 (20.0%). Midline shift (13.4%) and signs of herniation (4.5%) only occurred in group 3. The analysis of correlation/regression and receiver operating characteristics was able to predict 79% of patients' outcome accurately using GCS (r 0.54; P < 0.0001) alone, using CCT (r 0.65; P < 0.0001) 87% were correctly predicted with significant variables Cal-Fx, EDB, SAB and BS. CCT with GCS (r 0.74; P < 0.0001) were able to predict 88% accurately with significant variables Cal-Fx, EDB, BS and GCS. The combination of CCT with GCS, age and ISS (r 0.78; P < 0.0001) was able to predict only 87% correctly, although the r value was the highest; significant variable were Kal-Fx, EDB, BS, VL, GCS, age and ISS.

Adolescent↗

PubMed1997

Prehospital care, importance of early intervention on outcome.

The improvement of rescue systems and on-scene therapy has lead to a significant reduction of early posttraumatic death. It was the goal of this study to critically analyse the value of prehospital care in respect to early but also to delayed complications (single = SOF or multiple organ failure = MOF) In a retrospective analysis 1223 polytraumatized patients treated during 1984 and 1994, with an injury severity of more than 20 points according to the Injury Severity Score = ISS, on-scene therapy ("field stabilization") was evaluated. We could show that a sufficient preclinical airway management has major influence on late prognosis (MOF). We therefore definitely recommend early intubation at the scene in these patients. The intravenous access at the emergency place is always necessary independent whether the patient is in hemorrhagic shock or not. Loss of time can increase shock mechanisms making intravenous access even more difficult. If there is already a peripheral vasoconstriction and the localisation of an peripheral vein renders more difficult, one possibility is a venae section to get safe access. Concerning the amount of preclinical infusion controverse opinions exist. Our evaluation could not give an satisfactory statement because of a differing high incidence of mass bleeding in the groups with low (< 1000 ml) and high (> 2000 ml) preclinical infusion. The improvement of rescue systems and on-scene therapy has lead to a significant reduction of early posttraumatic death. Especially in those injuries, that are directly associated with the development of early death, i.e. intracranial bleeding, massive hemorrhage from thoracic and intraabdominal lesions these regimens on scene improved survival significantly (Fig 1) (Trunkey 1983). Nevertheless it is still discussed whether a longer rescue time is then justified to intensify on scene therapy. Recent publications demonstrate for instance that infusion therapy beginning on scene is not always necessary and sometimes especially in severe hemorrhagic shock can even aggrevate bleeding (Bickell 1989, Bickell 1991, Bickell 1993, Crawford 1991, Gross 1988, Stern 1993). On the other hand the value of on scene intubation and ventilation and chest tubing in these patients is critically discussed (Mattox 1989). Most of these studies however have their origin in the USA and are related exclusively to penetrating trauma (knife and gunshot wounds), which is completely different from underlying pathomechanisms (pure hemorrhagic shock). Only one reports of the same experience with blunt trauma (Barone 1986). Thus for severe blunt trauma the question is still open: "field stabilization" or "load and go" (Krausz 1992). A decision that always has to be related to the definite rescue time (Smith 1985). It was the goal of this study to critically analyse the value of prehospital care in respect to early but also to delayed complications (single = SOF or multiple organ failure = MOF).

Abdominal Injuries↗

PubMed1997

[Vascular segmentation with fuzzy and standard methods].

Explore the source record for details and available documents.

Angiography, Digital Subtraction↗

PubMed1997

[Functional, neuropsychological and social outcome of polytrauma patients with severe craniocerebral trauma].

The aim of this study was to identify, in (pre-) clinically obtained data, parameters predicting the outcome of patients with multiple trauma and severe head injury. Fifty-eight patients aged 27 +/- 10 years were investigated an average of 5.8 years after the accident. The Hanover Polytrauma Score was 34 +/- 11 points, the initially assessed Glasgow Coma Scale (GCS) was 6.2 +/- 3.2 points; and the duration of coma was 15.4 +/- 14.4 days. The primary length of stay in hospital averaged 33.4 days, including 22.9 days in the intensive care unit and 20.2 days of ventilation. For a further 223 days the patients were treated at the Neurologic Clinic of Hessisch Oldendorf. Besides different neurologic deficiency symptoms, the psychometric tests showed deficits in all areas. In particular, information processing speed, concentration, recent memory and learning performance were impaired. There was free mobility of all joints in 33% of the patients. Due to injury the elbow and ankle joint developed the worst restriction. Central paralysis and heterotopic ossification also caused a restriction in joint mobility. Half of the patients were confronted with different social changes. The rate of return to work was dependent on age. Some 42% of all patients had taken up their former profession, 5% were still in training or at college, 32% were retrained to other professions, 16% were unemployed and 5% were completely retired on pension. Age, injury severity, GCS, duration of coma and duration of weaning were suitable predictors in correlation- and regression analysis. The Glasgow Outcome Scale showed good recovery and moderate disability in 53%, severe disability in 33% and persistent vegetative state in 14% of the patients.

Activities of Daily Living↗

PubMed1996

[Multiple organ failure after severe trauma: predictable by the MEGX liver function test?].

Alanine Transaminase↗

PubMed1996

[Prognosis of polytrauma patients with severe craniocerebral trauma during the critical care phase].

In this study multiple trauma patients with severe head injury showed a different functional, neuropsychological and social outcome depending on several clinical parameters. In a stepwise regression analysis age, injury severity, Glasgow Coma Scale, length of coma and weaning time were proved to be suitable predictors. During the intensive care stay an early prognosis on severe head injury patients is possible.

Activities of Daily Living↗

PubMed1995

The influence of thioctic acid on metabolism and function of the diabetic heart.

Streptozotocin-diabetes as a model for insulin-deficient Type 1 diabetes leads to cardiomyopathy, characterized by a 50% reduced glucose uptake (P < 0.001) and increased lactate and pyruvate levels (P < 0.001), i.e. a reduced glucose utilization by the heart. As thioctic acid (TA) has favourable effects on glucose metabolism, the influence of this drug at two different doses (0.1 mg/ml and 0.5 mg/ml, added to the perfusion medium) was investigated in the heart after 2 weeks of diabetes, using the working rat heart model at physiological workload about 45 min. TA at high doses led to a normalization of glucose uptake (P < 0.001) and glucose utilization, and consequently to a normalization of oxygen uptake (P < 0.001), myocardial ATP levels (P < 0.001) as well as cardiac output (P < 0.05). Whereas a low dose of TA resulted in a normalization of lactate and pyruvate production (P < 0.001), neither a normalization of glucose utilization nor of cardiac output was achieved by this low dosage. Additionally, TA improved at both doses utilization of endogenous glycogen in the diabetic heart (P < 0.001), the latter here already delivering 45% of the utilized glucose. TA acts especially by increasing glucose uptake, glycogen breakdown and glucose oxidation. Thus, metabolic and hemodynamic sequelae of insulin-deficiency in the heart can be corrected by TA. Due to its anti-diabetic effects on cardiac metabolism, TA could be considered an adjuvant therapy in diabetic cardiomyopathy.

Adenosine Triphosphate↗

PubMed1995

Treatment results of patients with multiple trauma: an analysis of 3406 cases treated between 1972 and 1991 at a German Level I Trauma Center.

The quality and progress of treatment for 3406 multiple trauma patients was reviewed retrospectively. Two periods (1972 to 1981, the first decade, and 1982 to 1991, the second decade) were compared. Sixty-nine percent of patients with multiple trauma had cerebral injuries, 62% thoracic trauma, and 86% fractures (40% open fractures). Concerning injury combinations, there was an increase of head/extremity injuries and thoracic/extremity injuries, whereas all combinations with abdominal injuries decreased. The relation between severity of injury as well as number of injured body regions and the mortality rate was significant. In the second decade prehospital care became more aggressive with an increase in use of intravenous fluid resuscitation (from 80% to 98%), intubation (from 84% to 91%), and chest tube insertion (from 37% to 76%). Rescue times were progressively shortened. For initial clinical diagnosis of massive abdominal hemorrhage, ultrasound (89%) nearly replaced peritoneal lavage (10%) and led to earlier surgical approach. For diagnosis of head injury, CT scan was used more frequently. Primary stabilization of long bone fractures, especially of the lower limb, is recommended. Concerning complications, the change in volume therapy helped to nearly eliminate acute renal failure (from 8.4% to 3.7%), the modification of respirator treatment led to a decrease of pulmonary insufficiency (ARDS; from 18.2% to 12.0%), whereas the rate of multiple organ failure increased. The mortality rate declined from 37% in the first decade to 22% in the second decade. The incidence of lethal multiple organ failure increased from 13.8% in the first decade to 18.6% in the second decade, whereas the mortality rate of ARDS decreased from 32.4% to 15.9%. Further reduction of incidents of death is only possible with causal therapy of posttraumatic organ failure immediately after injury.

Accidents, Traffic↗

PubMed1995

Monoethylglycinexylidide as an early predictor of posttraumatic multiple organ failure.

The prognostic value of a dynamic liver-function test, based on the hepatic conversion of lidocaine to monoethylglycinexylidide (MEGX), in predicting multiple organ failure (MOF) was prospectively investigated in 28 critically ill patients after multiple trauma. The MEGX test and conventional static liver tests (bilirubin, aspartate aminotransferase, glutamate dehydrogenase, and factor V) were performed on days 1, 3, 5, and 7 after trauma. Patients were classified by a modified MOF score into a group without (n = 18) and a group with the MOF syndrome (n = 10). One patient who developed MOF on the basis of a bacterial septicemia was excluded from the general evaluation. No significant differences were observed in the MEGX values of the two groups on day 1. All patients who subsequently developed MOF, however, displayed a sharp decrease in their MEGX values between days 1 and 3. Analysis of the data using receiver operating characteristic (ROC) curves revealed that the results of the MEGX test on day 3 provided the greatest discriminating power between patients with and without subsequent MOF. A cut-off MEGX value of 30 micrograms/L on day 3 was associated with a prognostic sensitivity of 89% and a prognostic specificity of 94%.

Adult↗

PubMed1995

[Effect of primary fracture management on craniocerebral trauma in polytrauma. An animal experiment study].

Severe head trauma (BI) associated with long bone fractures is present in about 60% of polytraumatized patients admitted to hospital. However, there is no consensus regarding early fracture stabilization in such patients. In an experimental sheep study, the influence of intramedullary nailing of the femur (IMNF) on a cold-induced, vasogenic brain edema (method of Klatzo) in combination with traumatic hemorrhagic shock (THS) was investigated. Three animal groups (n = 6) were explored: group A, only BI; group B, BI and THS; group C, BI, THS and IMNF. The animals remained intubated, on controlled ventilation, sedated and received analgesia during the whole experiment. For a period of 6 h after the cold-induced brain injury the hemodynamic changes were measured and the intracranial pressure (ICP) was recorded in the left and the right hemisphere continuously. The hemorrhagic shock (MAP = 60 mm Hg) was maintained over 1.5 h. At the end of the reperfusion period (2 h) the nailing of the femur was performed. The animals were killed and the percentage water content of the brain was determined and compared with the brain water content of a control group (n = 6). There were no significant differences in ICP between groups A, B and C before or after IMNF, but in group C the ICP increased significantly after nailing. Brain water content in group C was significantly higher than in the control group and slightly significantly higher than in groups A and B. Brain edema and ICP are increased by IMNF.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1995

[Does initial management of polytrauma patients have an effect on the development of multiple organ failure? Evaluation of preclinical and clinical data of 1,112 polytrauma patients].

The aim of this study was to investigate criteria in the preclinical and early clinical treatment which contribute to the development of posttraumatic multiple organ failure (MOV). In a retrospective study, 1112 primarily treated patients with multiple trauma and an injury severity > 20 on the Hanover Polytrauma Score (PTS) were investigated. The patients were classified according to Goris into groups with MOV (+MOV; 16.8%) and without MOV (-MOV). Patients with MOV had a significantly higher injury severity score (39.1 vs 33.7). A significantly higher proportion of +MOV patients had severe trunk injuries: thorax (85.2% vs 68.9%), abdomen (37.0% vs 26.1%) and pelvis (49.4% vs 35.6%). -MOV patients had significantly more injuries of the extremities (83.6% vs 72.8%). Differences in preclinical management were seen. The proportion of helicopter transports was significantly higher in the -MOV group (67.9% vs 57.8%). A positive effect was seen for early preclinical intubation. Patients who were intubated before arrival at the hospital had the same rate of MOV incidence as late intubated patients, but they had significantly higher (trunk) injury severity. +MOV patients received a significantly higher quantity of fluid replacement. In particular, more blood units and fresh frozen plasma were given in the first 24 h after trauma, possibly in association with the trunk injuries and the consequently increased hemorrhage. The mortality for all patients was 27.2%, in the +MOV group 60.4%. Posttraumatic MOV was the most frequent cause of death (37.5%), and the mean time of death after MOV was 16.7 days.

Adult↗

PubMed1994

Refined mapping of the human Ets-related gene Elk-1 to Xp11.2-p11.4, distal to the OATL1 region.

The gene for human Elk-1, an Ets-related transcription factor, has previously been localized to a region that lies on the short arm of chromosome X and that is involved in specific chromosomal translocations associated with synovial sarcoma and renal adenocarcinomas. We have used fluorescence in situ hybridization and a panel of tumor-derived somatic cell hybrids to refine the localization of Elk-1, in particular with regard to the rearrangements in these tumors. Elk-1 has been assigned to Xp11.2-p11.4, distal to the OATL1 region.

Animals↗

PubMed1993

[Results of treatment of polytraumatized patients. A comparative analysis of 3,406 cases between 1972 and 1991].

The treatment data on 3,406 patients with multiple injuries were analyzed retrospectively from the viewpoint of quality control. The diagnosis, therapy, complications and course were documented and the treatment results of two decades (1972-1981 and 1982-1991) compared. Young people with an average age of 31 years were mostly affected: 86% had fractures (40% open injuries), 69% head injuries and 62% thoracic trauma. Head injury together with thoracic trauma was the most frequent injury combination and affected the duration of ventilation therapy and the intensive care course. The relationship between the kind and severity of injury [categorized according to the Hannover Polytrauma Score (PTS)] and the lethality rate was significant. Preclinical treatment (infusion, intubation, thoracic tube) has increased in the past decade, and rescue time has been shortened. For the initial clinical diagnosis, ultrasound and the CT scan have been used more frequently. In patient treatment the elimination of massive hemorrhage still has first priority. Primary stabilization of long tubular bones, mostly of the lower limb, is aspired for. Volume therapy has changed over the last decade, so the risk of acute renal failure has been nearly eliminated. Nowadays late complications, e.g., multiorgan failure, are well in the foreground. Today at Hannover Medical School the average intensive care time is 13.7 days and the hospitalization time 31 days. When the two decades were compared, mortality was seen to have declined from 40% to 18%. In the future if the mortality rate is to be reduced further, this can only be done by treating the cause of post-traumatic organ failure.

Adolescent↗

PubMed1992

Effect of ascorbic acid on neutrophil functions and hypoxanthine/xanthine oxidase-generated, oxygen-derived radicals.

The chemiluminescence of isolated neutrophils, stimulated with N-formyl-L-methionyl-L-leucyl-L-phenylalanine, latex, lipopolysaccharide from Escherichia coli, zymosan A, or 4 beta-phorbol 12 beta-myristate 13 alpha-acetate was inhibited up to 99% by the dose-dependent oxygen radical scavenging activity of 6 mmol/l ascorbic acid. The chemiluminescence of neutrophils in blood, stimulated with 4 beta-phorbol 12 beta-myristate 13 alpha-acetate, or with zymosan A was inhibited 35% or 48%, respectively, by 6 mmol/l ascorbic acid. Ascorbic acid, up to 6 mmol/l, did not inhibit the release of beta-N-acetylglucosaminidase and elastase from isolated neutrophils activated by the above stimulatory agents. During neutrophil/nylon fibre interaction ascorbic acid reduced the oxygen radical production dose-dependently (77% inhibition of the chemiluminescence response at 6 mmol/l ascorbic acid), whereas the adherence was unaffected. Hypoxanthine/xanthine oxidase-generated oxygen radicals were scavenged by ascorbic acid in a dose-dependent manner (99% inhibition of the chemiluminescence response at 100 mumol/l ascorbic acid). From these results, ascorbic acid can highly be recommended for animal experiments and clinical studies in patients with trauma, shock and sepsis and for studies to prevent or reduce reperfusion injuries.

Antioxidants↗

PubMed1992

Determination of human neutrophil elastase in bronchoalveolar lavage fluid: homogeneous immunoactivation versus heterogeneous enzyme immunoassay.

Elastase mass concentrations of bronchoalveolar lavage fluid were determined by a homogeneous immunoactivation and a heterogeneous enzyme immunoassay. There was an excellent correlation between both assay systems (y = 1.0376 . x + 1.311; r = 0.9901; n = 43) indicating the suitability of the immunoactivation method for the determination of elastase concentrations in bronchoalveolar lavage fluid as a matrix. Furthermore, dilution of bronchoalveolar lavage fluid samples did not influence the elastase recovery of either assay system.

Bronchoalveolar Lavage Fluid↗

PubMed1991

[Variations of cemento-enamel junction of human teeth. Literature review].

The paper gives an account of the variations of the cemento-enamel borderline. Till now, the most studies were conducted on ground sections. Only a few descriptions of the relationship between enamel and cementum along the circumferential junction can be find. The authors described 5 variations which were discussed: cementum meets enamel, cementum fails to meet enamel, cementum overlaps enamel, enamel overlaps cementum, undertermined type. These observations show the unpredictable variability of enamel-cementum junction. It should be noted that the relationship is not constant along the circumferential crown root demarcation line.

Dental Cementum↗

PubMed1987

Complexes of DNA hairpins and a single-stranded oligonucleotide detected by affinity chromatography and mung bean nuclease cleavage.

The emergence of a simple translation device consisting of an assembler strand (primordial mRNA) and RNA hairpins (primordial tRNA) is presumed to be an important step leading to the origin of life. The assumption of a non-enzymatic interaction of primordial tRNA and mRNA is experimentally approached. DNA hairpins containing five or more adenosine residues in the loop are able to bind to complementary oligonucleotides covalently bound to cellulose. The exact number of base pairs formed between the hairpins and the assembler strand is determined by two methods applied to DNA hairpin/assembler complexes. The melting temperature of a complex is measured and the cleavage pattern by nuclease from mung bean is determined. The loop of the smallest hairpin able to bind consists of five adenosine residues and only three base pairs are formed. This supports the idea of a primordial recognition similar to the contemporary codon-anticodon interaction.

Biological Evolution↗

PubMed1985

Chromatographic separation as selection process for prebiotic evolution and the origin of the genetic code.

A model for the evolution of a translation apparatus has been suggested where oligonucleotides in a hairpin conformation act as primordial adapters. Specifically activated amino acids are assumed to be attached to these hairpin molecules. For the specific activation, a chromatographic separation of, e.g. ala and CMP from gly and GMP can be accomplished on silica (e.g. of volcanic origin) with aqueous salt solutions. Other adsorbents like clays (kaolin, bentonite, montmorillonite), different silicates (florisil, magnesium trisilicate, calcium silicate, talc), hydroxyapatite, barium sulfate, calcium carbonate, calcium fluoride and titanoxide have been examined as model systems for the separation of nucleotides, nucleosides and amino acids on mineral surfaces. The possible role of chromatographic separation of amino acids for the formation of proteinoids, composed of selected amino acids, is also considered.

Amino Acids↗