Biomedical subjects

O Trentz

Publications and source records attributed to O Trentz.

At least 19 recordsLinked to original sources

PubMed2007

Immunohistochemical characterization of Fas (CD95) and Fas Ligand (FasL/CD95L) expression in the injured brain: relationship with neuronal cell death and inflammatory mediators.

Traumatic brain injury causes progressive tissue atrophy and consequent neurological dysfunction, resulting from neuronal cell death in both animal models and patients. Fas (CD95) and Fas ligand (FasL/CD95L) are important mediators of apoptosis. However, little is known about the relationship between Fas and FasL and neuronal cell death in mice lacking the genes for inflammatory cytokines. In the present study, double tumor necrosis factor/lymphotoxin-alpha knockout (-/-) and interleukin-6-/- mice were subjected to closed head injury (CHI) and sacrificed at 24 hours or 7 days post-injury. Consecutive brain sections were evaluated for Fas and FasL expression, in situ DNA fragmentation (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling; TUNEL), morphologic characteristics of apoptotic cell death and leukocyte infiltration. A peak incidence of TUNEL positive cells was found in the injured cortex at 24 hours which remained slightly elevated at 7 days and coincided with maximum Fas expression. FasL was only moderately increased at 24 hours and showed maximum expression at 7 days. A few TUNEL positive cells were also found in the ipsilateral hippocampus at 24 hours. Apoptotic, TUNEL positive cells mostly co-localized with neurons and Fas and FasL immunoreactivity. The amount of accumulated polymorphonuclear leukocytes and CD11b positive cells was maximal in the injured hemispheres at 24 hours. We show strong evidence that Fas and FasL might be involved in neuronal apoptosis after CHI. Furthermore, Fas and FasL upregulation seems to be independent of neuroinflammation since no differences were found between cytokine-/- and wild-type mice.

Animals↗

PubMed2006

Early experience with the retrievable OptEase vena cava filter in high-risk trauma patients.

OBJECTIVES: Prophylactic vena cava filters (VCF) are efficient in preventing pulmonary embolism. Filter retrieval avoids the potential long-term complications of permanent VCF. Clinical evaluation was focused on filter-related complications and feasibility of retrieval in high-risk trauma patients. METHODS: Analysis of single-institution consecutive case series of patients who received a prophylactic OptEase VCF after multiple trauma between 08/2003 and 12/2004. Data were collected prospectively. RESULTS: A total of 37 OptEase filters were inserted prophylactically after multiple trauma (median patient age 35 years, range, 17-73 years, median ISS 41, range, 17-59). All patients had contraindications for pharmacological prophylaxis for thromboembolic events. 32 filters (86%) were retrieved after 16 days (range, 7-25 days). 12 of 33 filters (36%) demonstrated trapped clots/thrombosis within the filter structure on pre-retrieval cavography. Two patients received anticoagulation before filter retrieval due to filter thrombosis (6%). Symptomatic PE was observed in 1 patient (3%) 5 days after VCF retrieval. Minor caudal filter migration was observed in 1 patient (3%). Overall mortality was 3%. CONCLUSIONS: Retrieval of the OptEase filter is safe and feasible. Temporary filter placement avoids possible long-term complications of permanent VCF. It is an efficient form of PE prophylaxis when temporary contraindications to anticoagulation are present.

Adolescent↗

PubMed2006

[Entrapment of the anterior tibial artery in a distal tibial fracture after intramedullary nailing].

We present a patient with a closed displaced distal tibia fracture with entrapment of the anterior tibial vessels in the fracture after tibial nailing. This complication was initially not recognised. After several debridements of the forefoot on the same side due to open metatarsal fractures and severe soft tissue injury, a free latissimus dorsi flap was used for covering the dorsum pedis. Preoperative angiography showed occlusion of the anterior tibial artery at the fracture line which was interpreted as a secondary occlusion due to an intima lesion of the vessel after injury. The entrapment in the fracture line was recognised intra-operatively during the preparation of the anterior tibial vessel.

Aged↗

PubMed2006

[Influence of V.A.C.-therapy on cytokines and growth factors in traumatic wounds].

OBJECTIVE: Clinical observations have shown an accelerated wound healing in wounds of patients treated by Vacuum Assisted Closure (V.A.C.)-therapy. The mechanisms of improved wound healing on cellular level have been hitherto less investigated. In this study the levels of proinflammatory interleukins (IL-6, IL-8, IL-10) and growth factors (VEGF, FGF-2) in serum and wound were monitored. METHODS: The study included 21 patients with traumatic wounds that could not be closed during the first surgical intervention. The soft tissue defects (n = 21) were closed temporarily by Epigard. During the first second-look operation after 2.0 +/- 0.2 days in an average, Epigard was used for another 2.5 +/- 0.4 days as temporary soft tissue coverage in 13 patients (group A). In the remaining 8 patients the wound conditioning was done by V.A.C.(R) for 2.4 +/- 0.3 days (group B). A total of 428 samples of serum and wound fluid samples were collected during the first and second look operation. Levels of IL-6, IL-8, IL-10, VEGF and FGF were measured specific by ELISA. RESULTS: In all interleukins and growth factors there were significant lower serum level concentrations compared with those in wound fluids. During the first temporary dressing change after wound coverage with Epigard the wound samples showed the following levels [Mean (SEM)]: IL-6 49 816 (19 889) pg/ml, IL-8 54 (16) ng/ml, IL-10 314 (44) pg/ml, VEGF 4 746 (766) pg/ml, FGF-2 494 (89) pg/ml. During the second dressing changes we monitored the following levels in group A: IL-6 7 218 (2 542) pg/ml, IL-8 69 (27) ng/ml, IL-10 261 (58) pg/ml, VEGF 3 551 (661) pg/ml, FGF-2 355 (67) pg/ml. In group B the samples of the wound fluid showed the following results: IL-6 16 966 (4 124) pg/ml [p = 0.02], IL-8 223 (91) ng/ml [p = 0.03], IL-10 233 (76) pg/ml [p = 0.38], VEGF 7 490 (1 565) pg/ml [p = 0.01], FGF-2 352 (43) pg/ml [p = 0.48]. CONCLUSION: The increased local release of IL-6, IL-8 and VEGF in wounds after V.A.C.-therapy may be involved in the accumulation of neutrophil granulocytes and angiogenesis, which seams to play a crucial role for the accelerated granulation tissue formation after V.A.C.-therapy compared to wounds treated by Epigard.

Compartment Syndromes↗

PubMed2006

Systemic effects of severe trauma on the function and apoptosis of human skeletal cells.

Systemic factors are believed to be pivotal for the development of heterotopic ossification in severely-injured patients. In this study, cell cultures of putative target cells (human fibroblastic cells, osteoblastic cells (MG-63), and bone-marrow stromal cells (hBM)) were incubated with serum from ten consecutive polytraumatised patients taken from post-traumatic day 1 to day 21 and with serum from 12 healthy control subjects. The serum from the polytraumatised patients significantly stimulated the proliferation of fibroblasts, MG-63 and of hBM cells. The activity of alkaline phosphatase in MG-63 and hBM cells was significantly decreased when exposed to the serum of the severely-injured patient. After three weeks in 3D cell cultures, matrix production and osteogenic gene expression of hBM cells were equal in the patient and control groups. However, the serum from the polytraumatised patients significantly decreased apoptosis of hBM cells compared with the control serum (4.3% vs 19.1%, p = 0.031). Increased proliferation of osteoblastic cells and reduced apoptosis of osteoprogenitors may be responsible for increased osteogenesis in severely-injured patients.

Adult↗

PubMed2005

Hypocretin-1 (orexin A) deficiency in acute traumatic brain injury.

Hypocretin-1 is involved in the regulation of the sleep-wake cycle. The authors prospectively assessed CSF hypocretin-1 levels in 44 consecutive patients with acute traumatic brain injury (TBI). Compared with controls, hypocretin-1 levels were abnormally lower in 95% of patients with moderate to severe TBI and in 97% of patients with posttraumatic brain CT changes. Hypocretin-1 deficiency after TBI may reflect hypothalamic damage and be linked with the frequent development of posttraumatic sleep-wake disorders.

Adolescent↗

PubMed2005

Effect of low molecular weight heparin (dalteparin) and fondaparinux (Arixtra) on human osteoblasts in vitro.

BACKGROUND: The prolonged administration of heparin for prevention and treatment of venous thromboembolism has been associated with a risk of heparin-induced osteoporosis. Fondaparinux is a new antithrombotic drug that specifically inhibits factor Xa. Because of the known interactions of other antithrombotic agents with bone remodelling, the effects of fondaparinux on human osteoblasts were analysed in vitro. METHODS: Primary human osteoblast cell cultures were incubated with either the low molecular weight heparin dalteparin at concentrations of 30, 300 and 900 microg/ml or with fondaparinux at concentrations of 25, 50, 100, 150, 200 and 250 microg/ml. Cellular proliferation rate and protein synthesis were measured. Expression of genes encoding osteocalcin, collagen type I and alkaline phosphatase was examined by reverse transcriptase-polymerase chain reaction. RESULTS: Incubation with dalteparin led to a significant, dose-dependent inhibition of osteoblast proliferation, inhibition of protein synthesis, and inhibited expression of phenotype markers (osteocalcin and alkaline phosphatase genes) after 3 and 7 days. No inhibitory effects were observed in the fondaparinux-treated cells. CONCLUSION: Fondaparinux did not inhibit osteoblast proliferation in vitro and may reduce the risk of heparin-induced osteoporosis associated with long-term heparin administration.

Alkaline Phosphatase↗

PubMed2005

[Influence of sacral fracture on the long-term outcome of pelvic ring injuries].

Initial treatment of pelvic ring fractures with involvement of the iliosacral complex is directed at bleeding control and fixation of the pelvic ring. However, long-term outcome is determined by persisting neurological deficits, malunion of the posterior pelvic ring with low back pain, and urological lesions. Between 1991 and 2000, 173 patients with sacral fractures were treated at our institution. Sacral fractures as part of type B2 ("lateral compression") or type C ("vertical shear") pelvic ring fractures were treated conservatively, if dislocation was less than 1 cm. Fractures with a dislocation of more than 1 cm were treated operatively (n=33, 19%). A total of 112 patients were examined after an average of 4.9 years. Of the 39 patients with primary neurological deficits (35%) only 4 showed complete neurological recovery. Chronic low back pain was rarely observed (n=8, 7%) and only in type C injuries. The low incidence of chronic low back pain justifies conservative treatment of minimally (<1 cm) displaced sacral fractures. Long-term outcome is largely determined by neurological deficits, which persist in 30% of all patients with sacral fractures.

Adolescent↗

PubMed2005

V.A.C. instillation: in vitro model. Part 1.

The reproducibility of a V.A.C. (Vacuum Assisted Closure) instillation system was investigated by means of an in vitro model. The relation between the volume of a delivered solution and its removal from the system was studied in foams of various size. The relationship of instillation time periods and the volume of delivered solution was determined.

Anti-Bacterial Agents↗

PubMed2004

Low molecular weight heparin-induced skin necrosis-a systematic review.

BACKGROUND: Low molecular weight heparins (LMWHs) are currently used as a standard for anti-thrombotic therapy. Skin necrosis caused by LMWH is a rare and probably under-reported complication. The aim of our systematic review is to analyse the present literature for cases of LMWH-induced skin necrosis, emphasising the pathogenesis, clinical pattern, and management of this rare side effect. METHODS: We performed a Medline literature search (PubMed database) and manual cross-referencing to identify all articles related to LMWH-induced skin necrosis. Data were analysed for type of LMWH used, time until skin necrosis occurred, localisation, size, laboratory findings, switch anticoagulant, complications, and outcome. Additionally, the case of a patient from our hospital is presented. RESULTS: We included a total of 20 articles (21 cases) reporting on LMWH-induced skin necrosis. Skin necrosis occurred locally and distant from the injection site. Heparin-induced antibodies were frequently observed (positive 9/11 articles, negative 2/11). However, severe thrombocytopenia (platelet count <100,000 cells/ml) occurred in only four cases, while platelet count remained normal in 50% of the cases. After patients had been switched to other anti-thrombotic drugs, the clinical course was usually benign; however, reconstructive surgery was necessary in two cases. CONCLUSION: LMWH-induced skin necrosis may occur as part of the heparin-induced thrombocytopenia (HIT) syndrome, but other pathomechanisms, including allergic reactions and local trauma, may also be involved. When HIT is excluded, unfractionated heparin is a safe switch anticoagulant. Otherwise, non-heparin preparations such as hirudin or fondaparinux should be preferred.

Anticoagulants↗

PubMed2004

[The role of transarterial embolisation in the treatment of patients with abdominal injuries].

INTRODUCTION: The role of transarterial embolisation in patients with abdominal injuries is controversial. Some trauma centres advocate routine angiography, whereas others believe in restricted indications such as increasing haematomas or persistent/recurrent haematuria. METHOD: We prospectively studied 167 patients with blunt and penetrating abdominal trauma. We used restricted indications for angiography and embolisation. RESULTS: Eleven of 167 patients with abdominal trauma (7%) were treated with angiography and embolisation., Overall, three of 11 patients (27%) with angiography and embolisation were treated emergently and eight of them (73%) at an average of 7.3 days. There were no complications due to the embolisation procedure, and all bleeding could be stopped. CONCLUSION: Transarterial angiography and embolisation is an important and safe tool in the treatment of acute abdominal injury when used for restricted indications. We believe this should not be performed as a routine procedure, especially in unstable patients.

Abdominal Injuries↗

PubMed2004

[Shock trauma room management of the multiple-traumatized patient with skull-brain injuries. A systematic review of the literature].

This overview reviews the literature on multiply injured patients with traumatic brain injuries. Clinical trials were systematically collected (MEDLINE, Cochrane, and hand searches) and classified into evidence levels (1 to 5 according to the Oxford system).A detailed analysis of the literature of traumatic brain injuries has been elaborated by the Brain Trauma Foundation and has been published in the World Wide Web (http://www2.braintrauma.org/). The following procedures should be performed in the emergency room for multiply injured patients with traumatic brain injuries: (1) recording of precise history to identify risk factors for severe traumatic brain injury, (2) measurement of the Glasgow Coma Scale (GCS), pupillary reflex, and mean arterial pressure, (3) diagnostic evaluation with a CT scan, and (4) rapid surgical decompression if indicated.

Clinical Trials as Topic↗

PubMed2004

[New application of v.a.C. (vacuum assisted closure) in the abdominal cavity in case of open abdomen therapy].

OBJECTIVE: The problem of the temporary vacuum assisted closure (V.A.C.) of open abdomen situation is that the fluids, following the negative pressure, pass the abdominal cavity and in case of a local infection disseminate over the whole abdominal cavity. METHODS: The usual open abdominal wound V.A.C. technique was modified by using an auxiliary, independently operating V.A.C. system positioned intra-abdominally and connected with a separate drainage tube introduced into the lateral abdominal wall. This arrangement prevents further spreading of a local intra-abdominal infection in case of a necrotising pancreatitis after traumatic pancreas rupture. RESULTS: The drainage volumes were comparable from superficial and intra-abdominal V.A.C. system. A total of 30 reoperations were necessary due to a leasion of the pancreas before a primary closure of the open abdominal wound could be applied after 72 days. No bowel fistulas or intra-abdominal abscess formations were observed. The follow-up have not shown any hernia of the abdominal wall up to the present. CONCLUSION: Additional intra-abdominally positioned V.A.C. system with an own drainage system supports open abdomen therapy with the standard abdominal V.A.C. system and prevents dissemination of intra-abdominal infection.

Abdominal Injuries↗

PubMed2004

[Reconstruction of posttraumatic bony defects of the lower extremity: callotaxis or free vascularized fibula graft?].

PURPOSE/BACKGROUND: Several methods have been established for the treatment of bony defects of the lower extremity. The purpose of this paper is to evaluate the use of a free vascularized fibula graft for these defects in comparison to callotaxis and segmental transport. METHOD AND CLINICAL MATERIAL: Retrospective analysis of data from 32 patients treated between 1981 and 1999 at the University Hospital in Zurich, Switzerland with bony defects of the lower extremity. RESULTS: The reconstruction of the bony defect was successful in 80 % with fibula graft, in 94 % with callotaxis and in 83 % with segmental transport. In the group with the fibula transplantation 2.6 re-interventions due to complications had to be performed, in the callotaxis group there were 3.6 and in the segmental transport group 5.2 surgical re-interventions. The time between primary intervention and full weight bearing was 16 months in the fibula transplantation group, 7.6 months in the callotaxis group and 10.7 months in the segmental transport group. CONCLUSION: The results show that these three options can be used for different indications. Reconstruction can be planned according to the following rules: Segmental bony defects of the entire circumference of up to 5 cm are best treated by initial shortening followed by callus distraction. Bony defects from 5 to 12 cm are best treated by segmental transport while maintaining limb length. Defects > 12 cm are best treated by reconstruction with a vascularized free fibula graft.

Accidents, Traffic↗

PubMed2003

[Cost analysis of acute therapy of polytrauma patients].

The rising costs of the Swiss health care system are currently a source of discussion. Precise facts about the treatment costs in Switzerland are not available. The aim of this paper is to assess the price of the acute therapy of multiple trauma patients at the University Hospital of Zurich. We analysed the exact treatment costs of 16 patients with an average Injury Severity Score (ISS) of 33.9. All these cases had a private or a supplementary insurance coverage, were foreigners or were otherwise invoiced according to the so-called hospital tariff (Spitalleistungskatalog/SLK). We developed a concept to measure the expenditure not covered by the insurance of those with a basic insurance, who entail the largest percent of all hospitalized patients. The average amount invoiced was 128,135 Swiss Francs (31,266-310,358 CHF). After subtracting the profit, gained on cases charged according to the SLK, the remaining deficit per ordinary insured was 42-65% or 33,703-138,829 CHF The range of this amount depends on the insurance status of the afflicted person. If hospitals are required to work with a balanced budget, then these losses can no longer be neglected. New forms of invoicing multiply trauma patients must be found in Switzerland.

Adolescent↗

PubMed2002

[Treatment of proximal ulnar comminuted fractures--a challenge].

INTRODUCTION: Comminuted fractures of the proximal ulna are severe injuries often complicated by involvement of the elbow joint and damaged soft tissues. The treatment of these fractures is very demanding and the results often mediocre due to of ancillary injuries (Dislocation in the humero-ulnar joint and associated radial head fractures). We analyzed the results of the treatment of these fractures and investigated whether other factors than the severity of fracture type influenced the final outcome. METHOD: Retrospective analysis of 18 patients with comminuted proximal ulna fractures. These comminuted ulna fractures included not only C-fractures according the the AO classification but also A1, A3, B1 and B3 fractures. Postoperative clinical and radiological examinations were routinely performed at 1/2-1 year intervals following treatment according to bone healing and work begin. This was done up to 48 months following treatment. Elbow function was recorded one year after the accident using the Morrey score. RESULTS: According the the AO classification, of the total of 18 patients, four suffered from an A-fracture, four from a B-fracture and 10 from a C-fracture. Eight of the 18 patients had an open fracture. 10/18 of the patients also had a fractured radial head and 9/18 of the cases had a dislocation of the humero-ulnar joint. The average range of motion based on a postoperative examination after one year was extension/flexion 0 degree/20 degrees/120 degrees and pronation/supination 70 degrees/0 degree/70 degrees. The assessment based on the Morrey-score indicated excellent to good results for 10 patients, average results for four patients and poor results for four patients. CONCLUSION: Despite correct diagnosis of the severity of injury and adequate treatment the results are only mediocre due to associated injuries (dislocation, radial head fractures). The goal is a stable anatomic reconstruction to allow early functional treatment.

Adult↗

PubMed2001

Prediction of psychiatric morbidity in severely injured accident victims at one-year follow-up.

The objective of this study was to assess the prevalence of posttraumatic stress disorder (PTSD) and symptoms of depression and anxiety in severely injured accident victims 1 yr posttrauma and to predict psychiatric morbidity by means of variables assessed shortly after the accident. The sample consisted of 106 consecutive patients with accidental injuries (mean Injury Severity Score = 21.9, mean Glasgow Coma Scale score = 14.4) admitted to the intensive care unit of a University Hospital. Patients with severe head injuries, suicide attempters, and victims of physical assault were excluded. At 1-yr follow-up, two patients (1.9%) had PTSD, and 13 (12.3%) had subsyndromal PTSD. Eighteen patients (17%) had clinically relevant symptoms of anxiety, and nine (8.5%) were depressed. Overall, 27 patients (25.5%) showed some form of psychiatric morbidity (full or subsyndromal PTSD and/or anxiety and/or depression). Logistic regression analysis, using 1-yr psychiatric morbidity status as the dependent variable, allowed correct classification of 83.8% of patients 12 mo postaccident (specificity 91.8%, sensitivity 61.5%). Biographical risk factors and a sense of death threat contributed significantly to the predictive model. We conclude that a substantial proportion of severely injured accident victims develop some form of psychiatric morbidity that can be predicted to some degree by mainly psychosocial variables.

Adaptation, Psychological↗

PubMed2001

Regulation of chemokines and chemokine receptors after experimental closed head injury.

The expression of the chemokines macrophage inflammatory protein (MIP)-2 and MIP-1alpha and of their receptors CXCR2 and CCR5 was assessed in wild type (WT) and TNF/lymphotoxin-alpha knockout (TNF/LT-alpha-/-) mice subjected to closed head injury (CHI). At 4 h after trauma intracerebral MIP-2 and MIP-1alpha levels were increased in both groups with MIP-2 concentrations being significantly higher in WT than in TNF/LT-alpha-/- animals (p < 0.05). Thereafter, MIP-2 production declined rapidly, whereas MIP-1alpha remained elevated for 7 days. Expression of CXCR2 was confined to astrocytes and increased dramatically within 24 h in both mouse types. Contrarily, CCR5 expression remained constitutively low and was mainly localized to microglia. These results show that after CHI, chemokines and their receptors are regulated differentially and with independent kinetics.

Animals↗