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L Schweiberer

Publications and source records attributed to L Schweiberer.

At least 181 records · Page 10Linked to original sources
PubMed1990

[Retro- and prospective studies on the value of clinical and laboratory chemical data in acute appendicitis].

In a retrospective study 536 appendicectomized patients were analyzed, in order to identify anamnestic, clinical and laboratory findings which allow the differentiation between acute and non-acute appendicitis. 150 consecutive patients were studied prospectively, which were referred to our department with a presumptive diagnosis of acute appendicitis. Eight single criteria were found, which exhibited a significantly different frequency in acute and non-acute appendicitis. Each criterion showed a low sensitivity and specificity; a score, which was created by combination of these single criteria also had low sensitivity and specificity. We conclude that the correct indication for appendicectomy highly depends on clinical experience of the surgeon.

Acute Disease↗
PubMed1990

[Treatment of defects of the long bones using distraction osteogenesis (Ilizarov) and intramedullary nailing. Theoretic principles, animal experiments, clinical relevance].

For large shaft defects of tibia and femur, distraction-compression osteosynthesis (Ilizarov) provides an ideal autologous bone graft. Combination of this with an intramedullary interlocking nail instead of an external fixator could improve patient comfort, because transport with a small external device takes only one-third of the total fixation period. Using 21 adult female sheep we created standardized tibia shaft defects 20 mm (medium size) and 45 mm (large size) in length. The tibiae were stabilized with non-reamed intramedullary interlocking nails. Following corticotomy by chisel, segments were transported using subcutaneous traction wires with a screw as a fulcrum to maintain stationary skin exit points without soft tissue problems. The external traction devices were removed after 12 or 16 weeks. Animals were sacrificed after 12 or 24 weeks with medium-size defects, and after 16 or 32 weeks with large defects. We evaluated the results clinically, by standardized weekly X-rays and, after sacrifice, by quantitative computed tomography (QCT). No animals had to be excluded from the study. Despite primary destruction of the intramedullary circulation all distraction gaps were spanned with bone. X-Rays showed typical signs of good quality of distraction bone regeneration (narrow radiolucent zone in the middle of the regenerate, longitudinal structure), continuous calcification, and cortex formation. QCT cross sections showed completely circular bone regeneration with small and large defects. Bone regeneration was faster on the dorsal side, where more bone was formed than ventrally. Small defects can remain ventrally in the regenerate; these close secondarily.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

[New bone formation following implantation of various hydroxyapatite ceramics. Animal experiment with bore hole models of the sheep tibia].

The aim of this study was to measure new bone formation after implantation of hydroxylapatite ceramic materials compared with autogenous and allogenous cancellous bone implantations. Eight standardised bore holes, each 6 mm in diameter, were drilled in the left medial tibia of each of seven merino sheep. Seven of these holes were filled with hydroxylapatite ceramic materials: Bio-Oss, Pyrost, autogenous and deep frozen allogenous spongiosa in various sequences. The empty hole was used for comparison. Results were evaluated after fluorescent marking with calcein green 6 weeks postoperatively. The extent of new bone formation was determined by means of fluorescence microscopy, microradiography and histological sections and quantified by means of an automatic surface-measuring programme. Whilst implantation of autogenous spongiosa resulted in almost complete slicing of the defect, the holes filled with hydroxylapatite ceramic materials showed no significant difference from the empty defect. We conclude that this purely inorganic material cannot stimulate new bone formation.

Animals↗
PubMed1989

Prognostic value of serum phospholipase A in the multitraumatized patient.

Phospholipase A serum activity was prospectively studied in 39 patients with multiple trauma. There was no correlation of phospholipase A activity with type or severity of injury. With increasing phospholipase A levels, a rise in mortality was found. A prediction of fatal outcome on an individual basis was not possible. The sensitivity for complications was 90%, whereas the predictive value of the positive test (64%) and specificity (47%) were low. When the behavior of phospholipase A and elastase release were compared, no correlation between these two parameters could be detected. Therefore, PMN leukocytes do not seem to be a major source of phospholipase A in serum.

Acute Kidney Injury↗
PubMed1989

Release of arachidonic acid metabolites during acute pancreatitis in pigs.

The pancreatic release of arachidonic acid metabolites was studied in a porcine model of acute pancreatitis. In situ isolation of the pancreatic gland enabled selective collection of pancreatic venous blood, pancreatic lymph, and ascites fluid. Three experimental groups were studied: 1) control (n = 9); 2) hemorrhagic pancreatitis induced by injection of 5% bile salt (sodium taurocholate) into the pancreatic duct (n = 10); and 3) edematous pancreatitis induced by injection of free fatty acid (FFA) into the pancreatic artery (n = 10). Determinations of cyclooxygenase metabolites were performed by radioimmunoassay; lipoxygenase metabolites (LTC4, LTD4) were measured by radioimmunoassay after purification by high-performance liquid chromatography. Prostaglandin (PG)F1 alpha, thromboxane B2, and PGF2 alpha concentrations were almost doubled in the lymph of the FFA group during pancreatitis, as were PGF1 alpha levels in pancreatic venous blood. However, concentrations of cyclooxygenase metabolites remained unchanged in the control group and in the bile salt group. Concentrations of LTC4 and LTD4 in lymph and ascites fluid of both pancreatitis groups increased from about 50 pg/ml to a mean level of 600 pg/ml at 6 h. Leukotriene concentrations in the control group were consistently below 50 pg/ml. The results of this study indicate that above all LTC4 and LTD4 are released from the organ and that these arachidonic acid metabolites may be also involved in the events following acute pancreatitis contributing to the systemic effects of the disease.

Acute Disease↗
PubMed1989

[Experiences with rotation atherotomy and atherectomy].

In addition to currently available, low risk procedures for reestablishment of patency in arteriosclerotic vascular segments with bougier techniques as described by Dotter and the balloon dilatation modification according to Grüntzig, as necessary together with local thrombolysis, important new developments based on mechanical principles are the atherectomy according to Simpson as well as the rotation atherotomy with a flexible catheter and slowly rotating milling head or rapidly rotating head as used by Kensey. To provide a larger lumen of recanalization, we developed an atherotomy lathing catheter with a rapidly rotating head and various diameters which is now available for intraoperative use. The thrombendarterectomy as described by Vollmar with the "ring stripper" is used only intraoperatively and can only be performed retrograde. The effect of laser systems encompasses disintegration and ablation of occlusive material. The rotation atherotomy is based on the capability of discrimination between hard occlusive material and elastic vascular wall through suitable construction of the lathe head (Figures 1 a to 1 e). Since, in passive catheters, the capability of lathing at the tip is associated with a high risk of perforation and a lateral possibility for lathing is not achievable, the lathing performance should be small, at the center of rotation and orthogonal to the axis of rotation at the outer radius. Through combination with a spherical disc face perpendicular to the axis of rotation, which protrudes only slightly from the hemispherical catheter tip, with a maximum at the center and minimum at the lateral borders, the lathing head has only a slight risk of perforation and no undesired sheering forces (Figures 2a to 2d).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

The impact of splenectomy on antibody response in the porcine model.

Some controversy exists regarding the antibody response after splenectomy and spleen preserving operations. In a porcine model the specific IgG antibody response to tetanus toxoid and type 6B pneumococcal polysaccharide was studied in 10 animals with splenectomy, 11 animals with splenic resection, 10 animals with splenic autotransplantation and 10 sham operated control animals. The operative groups were divided in two subgroups, receiving either the immuno adjuvant MTP-PE or the vehicle alone. Specific antibodies were determined by ELISA. Immunization with tetanus toxoid led to slightly lower peak IgG levels in splenectomized animals, but this was statistically not significant as compared to controls. In addition, the distribution of responders (78%) was not influenced by type of operation. Type 6B-pneumococcal polysaccharide proved to be a weak immunogen (19% responders). Splenectomy or spleen preserving surgery had no impact on the proportion of responders and peak IgG antibody titers of responders to this antigen. Additional administration of MTP-PE did not significantly increase the proportion of responders and had no impact on peak IgG antibody levels to tetanus toxoid and type 6B pneumococcal polysaccharide. These results show in contrast to previous studies in man, that under controlled conditions in the porcine model serum antibody responses to T-cell dependent and T-cell independent antigens are only slightly decreased by splenectomy. In addition, no effects of spleen preserving operations on antibody response are observed, and there is no change after concomitant administration of a muramyl peptide.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1989

Thoracic manifestations of internal pancreatic fistulas: report of five cases.

Thoracic manifestations of internal pancreatic fistulas are rare. During the last 8 yr, we have treated one patient with a mediastinal pseudocyst, three patients with pancreaticopleural fistulas, and one patient with a pancreaticobronchial fistula. Recurrent pleural effusions represent one of the main clinical features in this entity, and can often lead to false diagnoses. Determination of pancreatic enzyme activity, as well as the combination of ultrasonography, computerized tomography, and endoscopic retrograde cholangiopancreatography (ERCP), enable the establishment of the diagnosis. A complete pancreatic evaluation is the rationale for an adequate and efficient therapy which should always aim at a focal assentation.

Adult↗
PubMed1989

[Fractures of the spine].

The standard treatment for stable fractures of the spine is functional. Owing to the improvement of surgical methods and special implants, the percentage of operatively treated spine fractures has increased from 10% to 20%. In contrast to the necessity for multisegmental fixation with the rod instruments used formerly, the recently developed implants (plates, fixators) allow stable, brief, and therefore functionally more favourable immobilization.

Fracture Fixation, Internal↗
PubMed1989

[Changes and progress in fracture treatment of the proximal and distal lower leg].

In the treatment of proximal and distal tibial fractures, special attention has to be focused on the severity of tissue damage. Guidelines are given in the paper. (1) For tibial head fractures, stable internal fixation is usually necessary but should be delayed for 1 week. The best approach is lateral or ventral. The use of implants for buttressing has to be kept to a minimum. Concomitant ligamentous injuries are reconstructed, and damaged menisci should be preserved. (2) In the case of distal tibial fractures, those not involving the joint can be treated non-operatively. The internal fixation method by Ruedi is rarely indicated. When joint fractures involve tissue damage reconstruction is necessary. It is essential to achieve normal length of fibula. The joint is reconstructed with minimal use of implants. In addition, external fixation is usually necessary.

Adult↗
PubMed1989

[Fractures of the proximal humerus].

The Neer four-part classification for displaced proximal humeral fractures is the most useful classification so far devised for consistent diagnosis and treatment. Nevertheless, there are several points in the Neer classification that need changing. Group II fractures, i.e., displaced fractures of the anatomical neck have a severe prognosis, excluding a mild graduation as in group II. Displaced four-segment fractures can be classified in group IV as well as in group V, which means the classification less than sharp. Without disregarding Neer's criteria, we use our own simplified classification: group A: extra-articular non-displaced two- to four-segment fractures; group B: extra-articular displaced two- to four-segment fractures; group C: intra-articular impacted or dislocated two- to four-segment fractures. The prognosis following fracture treatment is heavily influenced by the outcome of avascular necrosis of the head. Additionally, surgical treatment offers the change of further devascularization. Rigid plate fixation leads to a high incidence of avascular necrosis. In the case of displaced fractures, we prefer open reduction and internal fixation by means of tension-band wiring. Screws have a limited use in the presence of decreased pullout strength in osteoporotic bone. A Neer II prosthesis is indicated as a primary procedure for impacted fractures of the humeral head, displaced or dislocated four-part fractures and dislocated three-part fractures in elderly patients. In other patients primary open reduction with internal fixation is preferred. Relief of impaction of the humeral head should be avoided. In case of a late osteonecrosis in younger patients hemiarthroplasty is indicated as a secondary procedure.

Fracture Fixation, Internal↗
PubMed1989

[Fractures of the distal end of the radius].

Attitudes to the treatment of distal radial fracture are now more critical than previously, especially where intraarticular fracture is concerned. Inadequate primary reduction and such complications as redislocation or dystrophic problems lead to poor results. Quantification of fracture instability is becoming increasingly important in fracture classification, determination of the indications for the different treatment modalities and management. Accurate anatomical reduction also improves later function. The quality of alignment attained during the treatment depends on the quality of reduction. Closed reduction by means of traction should be achieved by pulling on fingers I, II and IV. The radial dislocation should be corrected first and then the dorsal dislocation; a cast applied to the lower arm is sufficient for immobilization. Primary surgery is indicated more urgently and the type of surgery in more detail, for example, when there are steps in the articular surface or when there is more than one factor in instability. Pin fixation should be applied sooner and more frequently with either primary or early secondary indications. Plate fixation is mostly achieved from the volar surface; it is indicated in flexion fractures and sometimes in extension fractures, but only in combination with rigid screw fixation with or without bone grafting. We are finding increasingly more indications for external fixation, not only in the case of open fractures with soft tissue damage but also with multiple fragments or comminuted fractures, sometimes in combination with bone grafting.

Bone Nails↗
PubMed1989

[Changes and progress in fracture treatment in polytrauma].

The last 20 years have seen a great deal of controversy about the indications for and the timing of operative fracture treatment in multiply injured patients. In central Europe a standardized concept of treatment has been widely adopted since the late 1970s. In this concept a few types of fractures are given a high priority and are operated on early. Most fracture types, however, are not stabilized by internal fixation until several days after the injury. The treatment of closed femoral shaft fractures is still hotly debated. So far, not a single prospective study proving the advantages or disadvantages of early fixation has been published.

Fracture Fixation, Internal↗