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Biomedical subjects

L Schweiberer

Publications and source records attributed to L Schweiberer.

At least 109 records · Page 6Linked to original sources
PubMed1994

[Stabilization procedures in large soft-tissue and bone defects].

When stabilizing fractures with large soft tissue and bone defects, the primary concern is to avoid additional vascularization damage. Therefore, external fixation is still the standard method. In metaphysical fractures, joint transfixation should be avoided if possible. Concerning closed comminuted fractures of femoral and tibial shaft fractures, interlocking nailing shows the lowest complication rate. The introduction of unreamed nailing of open fractures shows the same low infection rate as external fixation, so it can be considered an alternative method. Early plate fixation is applied for fractures of the upper extremities as well as the proximal and distal femur, if secure covering with vital tissue can be provided. As this is not guaranteed in the case of the tibial shaft, plate fixation remains the absolute last resort. Concerning distal and proximal fractures of the tibial pylon and tibia head, plate fixation is very often applied for definitive stabilization. However, the secondary application represents a considerably lower infection and fracture-healing risk.

Adolescent↗
PubMed1994

[Possibilities in the reconstruction of bone defects].

The importance of the functional unit "bone-soft-tissue" for the treatment of bone defects is discussed. A division is made between non-vascular and vascular bone transport. The individual methods are explained and their clinical significance is illustrated partly using case material. In general, the best way to fill small defects in vital soft tissue is to use cancellous autografts. For bridging longer bone defects callus distraction is the method of first choice, but in individual cases vascularized bone transfer can be taken from the iliac crest or the fibula. Homo- or heterografts should only be used in cases where no autologic bone material is available or when there is not enough.

Arm Injuries↗
PubMed1994

[Stabilizing procedures in tumor-induced bone defects of the pelvis and extremities].

With malignant tumors of the skeleton the same therapeutic limb-saving guidelines must apply for the proximal sections of the locomotor system--the shoulder and pelvic girdles--as for the limbs themselves, especially since amputation here can hardly be surpassed by other resectional interventions with respect to operative risk, disfigurement and functional loss. The possibilities of surgical therapy for tumorous invasion of the pelvic girdle and the extremities are considered in some detail.

Adolescent↗
PubMed1994

[Treatment concept in infected bone and soft-tissue defects].

The first priority when treating infected bone and soft-tissue defects is the maintenance or reconstruction of vitality, vascularity and stability. This means that when signs of infection are apparent, this is an immediate indication for operative revision with protective preparations on the tissue and radical debridement. Treatment of the soft-tissue damage is carried out with local or microsurgically connected muscle flaps. As for stability, in early infection the retention of well-bonded implants is often possible. If not, it is often necessary to change over to external fixation. Reconstruction of bone damage is carried out after the infection recedes, and complete healing is finally achieved by further treatment changes to conservative means or further stabilizing treatment.

Adolescent↗
PubMed1994

[The contribution of the general and trauma surgeon in neurotraumatology: experiences and results of 10 years].

In acute medical service, general and traumatic surgeons are faced with the problem of treating severe head and brain injuries. In the department of surgery of the University Hospital in Munich, we have been performing neurotraumatological treatment since 1982. Within 10 years we saw 138 patients with severe head and brain injury. We had 48 cases of epidural hematoma. 81 of acute subdural hematoma. 84 of intracerebral contusional bleeding, 5 of depression fractures and 3 of hygromas. All these patients underwent surgical treatment. Osteoplastic trepanation was performed in 49 patients and osteoclastic trepanation in 60. Further interventions were elevation of the 5 depression fractures and evacuation of the 3 hygromas. Comparison with other investigations in departments of neurological surgery in the United States suggest that our results reflect a similar outcome (according to Jennet and Bond's outcome scale: 1, cured; 2, slightly handicapped; 3 severely handicapped; 4, vegetative state; 5, expired). The Traumatic Coma Data Bank (1991) recorded outcome of severe head and brain injuries as follows: 1, 27%; 2, 16%; 3, 16%; 4, 5%; 5, 36%; and our own results were: 1, 24%; 2, 17%; 3, 15%; 4, 5%; 5, 39%. Organization procedures and treatment strategies are suggested.

Adolescent↗
PubMed1994

[Increased pre- and postoperative thrombocyte activity in vascular surgery patients].

To determine the effect of vascular surgery on platelet function, a perioperative investigation of 37 patients with peripheral arterial disease (PAD) was performed using the Stagnation Point Adhesio-Aggregometer (SPAA). The SPAA provides well defined flow conditions. By means of dark field microscopy platelet microthrombus formation can be directly observed and measured continuously. Mathematical evaluation of resulting growth curves renders the constants for adhesion and aggregation, Kpw and Kpp, respectively. The PAD patients were divided into 2 groups: diabetics (n = 9) and nondiabetics (n = 28), and were examined perioperatively at regular intervals (average: n = 8). Preoperatively all patients received aspirin and low molecular weight heparin (LMWH). As of surgery and up to the third postoperative day all patients received unfractionated heparin (UH), at which time LMWH was resumed. Plasma fibrinogen concentration was also determined. Data obtained preoperatively were compared to those of 40 healthy volunteers (without medications). In the present study a significant increase (p < 0.001) in platelet reactivity was verified in PAD patients in spite of aspirin and LMWH administration. As of the first and up to the 8th day after surgery, a marked increase in platelet adhesivity and aggregability as well as plasma fibrinogen concentration and a concomitant decrease in platelet count was observed. Maximum values were obtained during intravenous administration of UH. Thrombocytopenia (< 150,000/ml) was observed in 12 patients. The hypercoagulability response to vascular surgery observed in the present study occurred in spite of therapy with aspirin and heparin. Our findings indicate the need for further improvement in conventional therapy and the SPAA as a useful tool in monitoring the effectiveness of current as well as of future inhibitors of platelet function.

Adult↗
PubMed1994

[Operation planning of secondary interventions after polytrauma].

A prospective study of 135 secondary operations (> 24 h after trauma) in patients with multiple injuries (ISS 40.6 pts) was performed to determine specific and unspecific indicators of the inflammatory response that may indicate the degree of risk of postoperative organ failure in these patients. On the morning of the operation each patients' data were recorded and blood samples were collected. Patients were divided in those in whom respiratory, renal and/or hepatic failure developed or preexisting organ failure worsened by more than 20% from baseline within 2 days after the operation and those who had no complications. In 29 patients who were operated upon between 24 and 72 h after trauma only the pO2/FiO2 ratio allowed discrimination between the two groups. The overall accuracy of this parameter as a predictor of postoperative organ failure was 83%, with a sensitivity of 78% and a specificity of 85%. In 106 patients with secondary operations later than 72 h after trauma, neutrophil elastase, C-reactive protein and platelet count revealed the highest predictive accuracy, with cut-off values of 250 ng/ml, 11 mg/dl and 180 x 10(6)/ml, respectively. The combined accuracy of these three parameters in prediction of postoperative organ failure was 79% (sensitivity 73%, specificity 83%). In this group of patients the pO2/FiO2 ratio was of less value and blood pressure, heart rate, renal function parameters, lactate and coagulation parameters were of no value.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute-Phase Reaction↗
PubMed1994

[Early mortality in polytrauma. A critical analysis of preventable errors].

In order to assess the impact of errors on outcome and to identify the rate of preventable deaths we investigated 40 premature deaths that had occurred among polytraumatized patients (blunt trauma; average ISS 53 points) in a prospective study (years 1986-1992) in a level I trauma centre. On analysing the patients' course on the basis of a complete set of data we detected 41 management and timing errors, 15 mistakes in treatment and 8 diagnostic problems. According to the significance of the errors the patients could be divided into three groups: in group 1 (n = 12; 30%) no errors were found, in group 2 (n = 22; 45%) there were errors but these definitely had no influence on the outcome, and in group 3 (n = 6;15%) we ascertained errors with a possible influence on the deaths. In none of the 40 cases of premature death could it be definitely shown that the adverse outcome could have been avoided. In the care of polytraumatized patients there was a clear predominance of management and timing errors insofar as they accounted for 64% of all errors that occurred and had frequently preceded possibly preventable deaths (88% in group 3). To diminish sources of error in the management of polytraumatized patients we must demand that more accurate clinical standards and algorithms be developed and introduced into the treatment of such patients.

Adolescent↗
PubMed1994

[An algorithm for management of shock in polytrauma].

The initial management of patients with multiple trauma requires a well-defined plan of action for immediate and adequate therapy, that ensures fast recognition of life-threatening conditions and injuries. While treatment protocols for specific situations and injuries are fairly well defined, there are few such concepts for the overall management process. Therefore, we designed a comprehensive algorithm for in-hospital trauma care to give priority-based guidelines to the trauma room physician. The full management plan (diagnostic and therapeutic interventions in sequence) is implemented in seven flow charts. The first algorithm starts with the initial assessment of immediate life-threatening disorders of A (airways), B (breathing) and C (circulation) and is followed by the early stabilization and maintenance of vital functions. It is followed by six interrelated flow charts, based on disturbed physiological functions (respiration, circulation) and anatomical injuries (thorax, abdomen, head/brain, spine/pelvic girdle/extremities), which are worked up simultaneously and repeatedly. This algorithm is not only intended as an overall guideline for use the management of severely injured patients, but is also indispensable for quality assurance.

Algorithms↗
PubMed1994

[Development of clinical algorithms for quality assurance in management of multiple trauma].

Resuscitation and management of high-risk multiple trauma patients require a systematic and coordinated approach to diagnostic and therapeutic interventions. Clinical algorithms with branch chain decision logic can provide a clear and organized transformation of clinical standards for trauma care. Owing to their capability in formalization and standardization, algorithms define precisely the process of care and serve as a central interface within the system of quality assurance and quality control. The standardized document symbols and conventions for information processing according to ANSI/ISO/CCITT regulations are generally applied to the flowchart design of clinical algorithms. Special starting and ending point symbols make it possible to break down complex processes in several single interrelated algorithms. Inclusion of optional criteria checklists reduces the number of decision nodes and loops and minimizes the extent of a comprehensive algorithm. Clinical algorithms are an excellent tool for converting highly complex concepts of multiple trauma management into a logical, prioritized and systematic process of care.

Algorithms↗
PubMed1994

Force required for bone segment transport in the treatment of large bone defects using medullary nail fixation.

In distraction osteogenesis, different factors influence quality and quantity of bone formation. These factors are rigidity of fixation, frequency, and velocity of transport; and integrity of periosteum, endosteum, and intramedullary vascularization. Little data are available on forces related to distraction osteogenesis and limb lengthening, and no data on forces related to bone segment transport. This experiment investigates the correlation of the bone regeneration process with transport forces. Bone segment transport over an intramedullary nail provides an excellent model for measurement of external forces during distraction osteogenesis because soft-tissue and muscle resistance is reduced as compared with limb lengthening. In an animal experiment (sheep), tibial shaft defects of 20 mm and 45 mm were treated. External transport forces were measured daily during bilateral wire transport of a bone segment over an intramedullary nail. Forces increased during transport. Overall transport forces for large defects were slightly higher than those for small defects, reaching 350 N by the end of transport. For large defects, transport forces leveled off during bone transport and rose again at the end. Correspondingly, for large defects, stress relaxation within the tissues increased during the third and the sixth week of transport. This plateau may be interpreted as a reduction of internal forces within the repair tissues at the distraction site, implying a spreading of the healing phases during the bone regeneration process or geometrically different shapes of the regenerate.

Animals↗
PubMed1994

[Practical and theoretical limits of score systems].

Trauma-scoring is a measurement of injury severity. Before conclusions can be drawn from their results, their validity, reliability and practicability need to be known. With respect to these factors the following statements may be proposed: some scores do have relatively low inter-rater reliability; retrospective interpretation of findings and diagnoses in the patient records may be equivocal; parameters contributing to the score may be lacking in some records; scoring may be time-consuming; the parameters selected to make up the score may not include all the relevant ones; the influence of time is neglected; different methods of patient selection may confound the interpretation of scoring results; most scores are only evaluated with respect to mortality; the scores are interpreted exclusively on the basis of statistical probabilities. We suggest that such scores as the ISS, PTS, (R)TS, which have been fairly well studied with respect to validity, reliability, and practicability, be prepared.

Humans↗
PubMed1993

[Enzyme liberation and activation of the kallikrein-kinin system in experimental pancreatitis. Studies of portal vein blood, pancreatic lymph and peritoneal effusion].

The clinical course of acute pancreatitis is strongly influenced by secondary cardiac, pulmonary and renal damage. The aim of the present study was to gather information about the compartment promoting the systemic damage. Therefore the activity of lipase, phospholipase A and plasma pro-kallikrein and the concentration of tissue kallikrein and kininogen were measured in portal venous blood, pancreatic lymph and peritoneal exudate. Anaesthetized pigs were subjected to fluid resuscitation to keep systemic haemodynamic parameters constant. The pancreas was isolated in situ. The pigs were randomly assigned to a control group (n = 9) or one of the two pancreatitis groups (n = 10 each). Pancreatitis was induced by i.a. infusion of free fatty acid (FFS) or retrograde infusion of 5% sodium taurocholate intraductally (NaT). In both pancreatitis groups the activity of lipase and phospholipase A increased. The most pronounced changes were seen in the peritoneal exudate (phospholipase A activity 40 min after induction: control 10.0 U/l, NaT 72.2 U/l). In both pancreatitis groups there was evidence for activation of the tissue kallikrein kinin system in the form of an increase in the kallikrein concentration and a decrease in the kininogen concentration. Again the changes were most pronounced in the peritoneal exudate (tissue kallikrein 40 min after induction: control 14.7 ng/ml, NaT 452 ng/ml).

Acute Disease↗
PubMed1993

Increased serum concentrations of procollagen type III peptide in severely injured patients: an indicator of fibrosing activity?

OBJECTIVES: To determine the serum concentrations of procollagen type III peptide in severely injured patients with different outcomes and to evaluate the relationship between serum procollagen type III peptide concentrations, sources of increased posttraumatic fibrotic activity (wounds, lung, liver, kidney), and decreased elimination of procollagen type III peptide (liver). DESIGN: Prospective study. SETTING: Surgical ICU, university hospital. PATIENTS: Fifty-seven patients (mean injury severity score: 38.5 points, range 13 to 75 points), between 16 and 70 yrs of age, treated in our institution within 6 hrs after the accident. MEASUREMENTS: Serial measurements were started on admission and continued on a 6-hr basis. After 48 hrs, the monitoring interval was extended to 24 hrs until recovery (but at least until day 14) or death. At each point of evaluation, pulmonary and circulatory function parameters and chest radiographs (once a day) were evaluated, the results were recorded, and blood samples were drawn to determine procollagen type III peptide, total bilirubin, creatinine, gamma-glutamyl transferase, polymorphonuclear elastase, and other parameters. Statistic evaluation was done with the Wilcoxon test, Spearman rank correlation, and a multiple regression model. RESULTS: Mean procollagen type III peptide serum concentrations (+/- SD) were significantly different in patients who died (8.0 +/- 3.8 U/mL) compared with those patients who survived with organ failure (2.7 +/- 1.3 U/mL) or without complications (1.4 +/- 0.5 U/mL), respectively. Significant correlations of procollagen type III peptide concentrations with the serum bilirubin concentrations (r = .7), days with need of mechanical ventilation (r = .64), PaO2/FIO2 ratio (r = -.6), polymorphonuclear elastase (r = .6), serum creatinine concentrations (r = .55), and injury severity score (r = .33) were observed. There was a tendency toward higher serum procollagen type III peptide concentrations in patients with severe skeletal injuries. CONCLUSIONS: Serum procollagen type III peptide concentrations in severely injured patients may be considerably increased in correlation with injury severity and outcome. Procollagen type III peptide serum concentrations seem to reflect the sum of increased collagen formation from wound healing and fibrogenesis of mediator-related organ damage (especially lung) and decreased procollagen type III peptide excretion due to impaired liver function. Further data are necessary to evaluate the role of hepatic elimination in these patients.

Adolescent↗
PubMed1993

Inhibition of plasma kallikrein with aprotinin in porcine endotoxin shock.

Activation of the contact phase of coagulation has been implicated in the pathogenesis of septic shock. We wanted to determine if inhibition of plasma kallikrein can prevent arterial hypotension and liberation of kinins from kininogen, induced by an infusion of bacterial lipopolysaccharide (LPS) in anesthetized, ventilated 20-kg pigs. The LPS was given IV in a dose of 5 micrograms/kg/h for 8 hours. The plasma kallikrein inhibitor aprotinin, 537 mumol, was given IV during 8 hours, resulting in plasma levels above 10 mumol/L. Ten animals (SA) received LPS and aprotinin and ten randomized controls (SC) received LPS and saline. Kinin-containing kininogen was determined on the basis of the amount of kinin releasable in plasma samples by incubation with trypsin. Kininogen decreased to 58% +/- 4% of the baseline value without any difference between groups. This may indicate participation of other processes than degradation by plasma kallikrein in the decrease of kininogen. Arterial blood pressure was higher at 7 hours in the SA animals than in the SC group (101% +/- 11% vs. 68% +/- 8%; mean +/- SEM; p = 0.026). Fibrin monomer and C3adesArg plasma levels were attenuated by aprotinin treatment. These findings underscore the important role of the contact system in LPS shock.

Animals↗
PubMed1993

[Operative injury in spinal surgery in the management of polytrauma patients].

The release of indicators and mediators of the posttraumatic inflammatory response following spine surgery was measured in patients with multiple injuries. Eight of a group of 113 patients (mean injury severity score 36) who underwent delayed operative stabilization of vertebral fractures (> 24 h after trauma) were studied. The following significant postoperative changes of blood levels (median values, Wilcoxon signed-rank test) compared with the preoperative starting point were found: polymorphonuclear granulocyte elastase rose from 220 to 337 ng/ml, cathepsin B from 84.5 to 135.5 mU/l, C-reactive protein from 9.1 to 11.6 mg/dl, lactate from 9.6 to 15.2 mg/dl and neopterin from 6.9 to 15.2 nmol/l, while antithrombin III fell from 107.5% to 84%, platelet count from 102 to 88 x 10(9)/l and pO2/FiO2-ratio from 361 to 260. The alterations in the blood levels of these parameters following spine surgery showed a pattern similar, albeit of lesser magnitude, to that which can be observed after severe accidental trauma. We conclude that the additional activation of the inflammatory response following surgery for vertebral lesions should be taken into account when planning these operations in patients with multiple injuries.

Acute-Phase Proteins↗
PubMed1993

[Does laparoscopic appendectomy have advantages? Laparoscopic appendectomy in comparison with conventional appendectomy--an observational study during introduction of laparoscopy].

From October 1990 to October 1992 the first 23 laparoscopically operated patients were recorded. 11 patients retrospectively including a supplementary questioning to missing data, 12 patients prospectively with a follow-up 6-8 weeks later. They were compared with 35 from April 1991 to April 1992 conventionally operated and prospectively observed patients. Laparoscopy was performed on patients with subacute clinical signs. The median age was comparable. Acute appendicitis was histologically confirmed in 18% of the laparoscopically and in 80% of the conventionally operated patients. Operating time was in mean 110 minutes for laparoscopic and 65 minutes for open appendectomy. The postoperative complications for laparoscopy included 4 Douglas abscesses (2 x open and 2 x pararectal revisions), one peritonitis due to a defect Roeder-loop and an haematoma of the abdominal wall. One case of wound infection (3%), one pericoecal abscess which needed an ileoascendostomy and a postoperative fatigue syndrome were recorded for open appendectomy. The postoperative return to normal diet was faster for laparoscopy. Return to normal bowel habits, the need of analgesia and the nominal analogue scales concerning pain, quality of sleep, well-being and appetite showed no obvious differences between the two operation methods. The postoperative stay was on average 6.7 days for laparoscopy and 5.6 days for the open operation. The results show the severe complications which may happen when introducing this new operation method. The laparoscopic appendectomy should only be performed electively in subacute appendicitis or when diagnostic exploration shows an inflamed appendix. Careful rinsing of the operation site and perioperative antibiotic treatment are mandatory. We made good experiences when using a stapler for the removal of the appendix.

Adolescent↗