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A Ekkernkamp

Publications and source records attributed to A Ekkernkamp.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Emergency ultrasound for blunt abdominal trauma--meta-analysis update 2003].

Emergency ultrasound has established itself as a key procedure of primary diagnostic work-up for blunt abdominal and multiple trauma. However, in a systematic review published in 2001 ultrasonography turned out to provide an unexpectedly low sensitivity. We conducted an update of this analysis to investigate if test characteristics will be maintained including recent studies. Prospective trials published between January 1957 and January 2003 were identified using the Medline/Oldmedline, Embase and Cochrane Controlled Trials Register databases. The searching strategy comprised a manual search as well as a search along the world-wide web. Qualitative rating was carried out by two investigators using criteria proposed by the Centre for Evidence-Based Medicine, Oxford. We investigated a composite endpoint (i. e., free fluid and/or organ laceration) as well as the single criteria organ injury and free intraabdominal fluid collections. After calculation of two-by-two-tables, Summary Receiver Operating Characteristics (SROC) and Q* values were determined together with their 95% confidence intervals. The Q* value was proposed as the point of intersection where sensitivity equals specificity. In addition, a random effects model was employed to compute common positive and negative likelihood ratios (LR). By assessing the title and/or abstract, 349 of 957 papers contained potentially valid information for the purpose of this review. A total of 67 studies were deemed eligible, nine of which had to be excluded from meta-analysis because of dual publication. This left 58 trials allocating 16,361 subjects for statistical analysis. Despite a trend towards improved study designs observed during the past decade, the included trials were of average methodological quality. Two-thirds of all investigations fulfilled two or less of the six possible quality criteria. The diagnostic reference standard was applied independently in only 40% of all protocols. With regard to the composite endpoint and the sonographic depiction of free fluid, the Q* value was estimated at 0.91, whereas Q* equaled 0.90 for the detection of organ injury. Q* values subsequently decreased with improving study quality and fell clearly below 0.80 in methodologically proper studies. Accounting for a negative LR of 0.23 (composite endpoint) and an assumed prevalence of 35% of intraabdominal injury, a post-test probability of 11% will remain in case of a negative sonogram. In pediatric trauma, ultrasound showed even worse test characteristics (negative LR = 0.43). Thus, in case of a 35% prevalence, the post-test probability has to estimated at 19%. Emergency ultrasound provides high specificity but insufficient sensitivity to reliably rule out intraabdominal injury.

Abdominal Injuries↗
PubMed2003

A likelihood ratio approach to meta-analysis of diagnostic studies.

OBJECTIVE: To develop a clinically and methodologically sound approach to diagnostic meta-analysis. METHODS: Two-step model was used involving four fictitious sets of 10 studies each with varying sensitivity and specificity; this was followed by the application of the method to data from a published systematic review of emergency ultrasound. Multidimensional test characteristics (relating to the detection or exclusion of the condition of interest) were described by likelihood ratio scatterplots and pooled likelihood ratios. Likelihood ratios summarise the ability of a test to revise the prior probability of disease. They can be summarised by established fixed-effects and random-effects methods. RESULTS: Likelihood ratios precisely describe both directions of test performance. By plotting positive against negative likelihood ratios, together with their 95% confidence intervals, a multidimensional forest plot is obtained that can be interpreted in analogy to therapeutic meta-analyses. There are accepted threshold values of positive and negative likelihood ratios (i.e. 10.0 and 0.1) to recommend a test for clinical use. In the matrix space, distinct test characteristics can even be assessed by eyeballing. With regard to data from the real meta-analysis, the suggested high discriminatory power of ultrasound was only partially qualified by likelihood ratios. The positive value confirms the reliability of a positive scan, whereas the negative value questions a normal sonogram. CONCLUSIONS: A full characterisation of test performance requires multidimensional effect measures. Likelihood ratios are recommended descriptors of the two dimensions of diagnostic research evidence and provide a convenient means to visualise and to communicate results as weighted summary estimates of a diagnostic meta-analysis.

Diagnosis↗
PubMed2002

[Risk evaluation in German clinics. Results of a survey].

INTRODUCTION: Risk evaluation is essential for the choice of individual surgical therapy. The aim of this survey was to examine whether preoperative risk analysis is routine in surgical therapy. METHODS: A questionnaire was sent to 1,159 clinics to assess how preoperative risk was evaluated and who carried out the evaluation. In addition, the factors used to determine the postoperative course and the way in which postoperative complications were observed were established. RESULTS: A total of 636 clinics filled out the questionnaire. Preoperative risk factors substantially influenced the postoperative course. The ASA classification was the most commonly used. Anesthesiologists together with surgeons evaluated the preoperative risk in 67% of cases. No preoperative risk evaluation was made in 12% of the clinics, and 21% did not record the postoperative complications regularly. CONCLUSIONS: Risk evaluation and control of postoperative complications are an important part of good clinical practice.

Germany↗
PubMed2002

[Mobility of unstable fractures of the odontoid during helmet removal. A biomechanical study].

In severe motorcyclist accidents unstable injuries of the cervical spine can usually not be excluded before an X-ray has been taken in the hospital. Despite this the helmet has to be taken off at the place of the accident in order to provide adequate treatment and airway management of the injured driver. There are no data in the current literature showing what happens to unstable lesions of the cervical spine during helmet removal. An experimental unstable lesion of the cervical spine was created by an osteotomy of the odontoid in 10 fresh frozen cadavers with intact soft tissues. All motions occurring in the segments C1-2 and C2-3 during helmet removal were recorded by fluoroscopy. The average motion in the unstable segment C1-2 was 23.7 degrees during a full range of extension-flexion movement of the cervical spine without any signs of dislocation of the segment. After application of the helmet there was one case of dislocation of C1-2 in neutral supine position already, and two further cases of dislocations during helmet removal. The average motion of C1-2 recorded during helmet removal was 19.0 degrees (2-25 degrees ), median 18.0 degrees. In order to avoid fracture dislocations and motion in the unstable upper cervical spine the helmet should better be cut in pieces at the place of the accident. There is a need for discussions with helmet producers to develop a new generation of helmets that can be removed easily without manipulating the head.

Accidents, Traffic↗
PubMed2002

[Does hospital structure influence the outcome of operative treatment of femoral neck fractures?].

UNLABELLED: Data on 32 007 patients suffering from a medial fracture of the femoral neck have been collected between 1993 and 1999 in a database for external quality assurance organized by the chamber of physicians in Westfalia-Lippe. A statistical analysis (ANOVA, chi-square-test) has been performed to find out whether factors like specialization, annual volume or level of the hospital (primary, secondary or tertiary hospital) influence the outcome. RESULTS: Patients with higher preoperative risk-factors are treated more often in primary hospitals. These clinics perform conservative treatment significantly more often than tertiary hospitals (6.5 % vs. 3.8 %). Osteosyntheses are performed more often in departments specialized in traumatology (13 %) or tertiary hospitals (16.8 %). Preoperative length of stay was 0.5-0.7 days shorter in these hospitals. There is no significant difference in postoperative complications all together (23.2-25.6 %), but a significantly lower rate in postoperative complications after osteosynthesis performed by departments specialized in traumatology (11.3 % vs. 18.8 %). A volume load of more than 50 cases per year correlates with a significant decline in postoperative complications (22.5 % vs. 28.2 %). Risk adjusted mortality does not show significant differences among the different levels of hospitals. CONCLUSIONS: There are distinct differences regarding the way of treatment and procedural quality, but not concerning the short-term outcome between hospitals of different levels.

Arthroplasty, Replacement, Hip↗
PubMed2001

Shed L-selectin (sCD62L) load in trauma patients.

BACKGROUND: Low circulating plasma concentrations of the leukocyte adhesion molecule L-selectin (sCD62L) were found to be associated with an increased risk for subsequent lung failure and case fatality after severe trauma. The objective of this study was to determine the robustness of soluble L-selectin, correcting for a broad spectrum of physiological variables. METHODS: Patients with suspected multiple and/or trunk injuries were enrolled into this study over a 1-year period. Plasma samples were obtained on hospital presentation, and circulating soluble L-selectin was measured with a commercially available ELISA kit. Study records comprised all relevant clinical and laboratory data. Thirty-day survival rate, subsequent acute lung failure, and nosocomial pneumonia were defined as study endpoints. Statistical analysis was performed using multivariate logistic regression models. RESULTS: Seventy patients with a mean age of 35.51 years (range, 10-87 years) and a mean ISS score of 36.61 (95% CI, 31.08-42.14) entered the study. Eleven patients died, leading to an attributable mortality of 15.70%. L-Selectin levels did not differ between survivors and nonsurvivors. Five patients progressed to acute lung injury, whereas 11 patients developed hospital-acquired pneumonia. Lower L-selectin levels indicated patients at risk for lung injury with a relative odds estimated at 4.43 (P = 0.017). Statistical significance diminished in the multivariate model. In contrast, plasma concentrations of circulating sCD62L were significantly decreased in patients developing nosocomial pneumonia (P = 0.023), with a twofold increased relative odds (OR, 1.96; 95% CI, 0.51-7.50). No effect modification was observed by the included covariables. CONCLUSIONS: The results of this study highlight the independent predictive value of initially decreased soluble L-selectin levels for the identification of patients susceptible to subsequent respiratory complications after severe trauma.

Adolescent↗
PubMed2001

[Femoral neck fracture in the younger patient. Contrast between guideline and management reality--results of external quality assurance in 1,747 follow-up cases].

UNLABELLED: Between January 1993 and December 1998 26.005 patients with hip fractures underwent treatment in departments of general surgery and traumatology in Westfalia-Lippe, Germany. Data of these patients were reported to the chamber of physicians where a report card system for external quality assurance has been established since 1991. 1.747 patients were between 10 and 60 years of age. Treatment according to the guideline of hip fractures of the German College of Traumatology is compared to treatment in reality. RESULTS: Conservative treatment declined to 2% in 1998; only 43% of these comparetively young patients were labeled as emergencies. Only 45.4% of all osteosyntheses were performed on the day of hospital admission. Almost 30% of the patients undergo hip replacement as first line therapy. Timing of operation is related to the frequency of operations per department and specialisation: the more operations per year the shorter the length of stay before operation. Early treatment is more likely in departments of traumatology than in departments of general surgery. Lethality and morbidity do not increase with early treatment. CONCLUSIONS: The reality of treatment of hip fractures does not meet the criteria of the guideline. Further efforts have to be undertaken for the benefit of relatively young patients with hip fractures.

Adolescent↗
PubMed2001

[Spinal epidural hematoma as a sequelae of knife stab injury. A diagnostic problem?].

Spinal epidural hematoma are a rare but serious complication of thoracic stab wounds. Their incidence should always be taken into consideration when first examining the patient, and it is also necessary to be able to find proof in either MRI or CT-scan. In our case the patients diffuse neurologic symptoms connected with a rather unreliable appearing personality made the diagnosis even more difficult. Initially it was possible to show the defect only in MRI.

Adult↗
PubMed2001

[Value of magnetic resonance tomography (MRI) in diagnosis of triplane fractures of the distal tibia].

The rare transitional fractures occur in adolescents at a time of incomplete dosis of the epiphysis. The anatomy of this fracture type is complex with the fracture line running in multiple planes. Conventional plain film radiographs often underestimate the extent and geometry of the fracture due to its transverse components. This study was performed to asses the benefit of MR-imaging compared to plain film radiographs in diagnosis and analysis regarding fracture-type, anatomy and dislocation of fracture. During a time period of 18 months we treated 15 patients with a fracture of the distal tibial epiphysis. In addition to plain film radiographs they got MRI of the distal tibia. Plain film radiographs and MRI were anonymized and diagnosed by 2 surgeons and 2 radiologists. 12 transitional fractures were diagnosed in plain radiographs as well as MRI, but regarding our criteria as above, we found two wrong classifications of fracture-type, an underestimation of fracture dislocation of an average of 0.5 mm in plain film radiographs and two rotational dislocations were missed. The MRI was found to provide anatomical detail and information superior to plain film radiographs.

Adolescent↗
PubMed2001

Immune response to perforated and partially demineralized bone allografts.

Immune responses have been shown to be involved in the pathogenesis of clinical complications of cortical bone allografts. In an attempt to reduce the immunogenicity of these allografts, we evaluated cortical bone allografts modified by laser perforation and partial demineralization transplanted orthotopically into sheep tibiae. The recipient animals were divided into three groups, of eight animals each, according to the type of cortical allograft that was transplanted: group 1, no treatment (control); group 2, demineralization only; and group 3, laser perforation and partial demineralization. All animals were tissue-typed by biochemical definition of MHC class I molecules, using unidimensional isoelectric focusing and Western blotting. Mismatches of donors and recipients were assessed by testing samples of each donor and recipient pair in parallel and by comparing their individual bands. Donor-specific alloantibodies were detected by a similar technique, using an enzyme-linked immunosorbent assay (ELISA) format. Negative controls were included in all tests. All grafts were poorly immunogenic, whether they were untreated, processed by partial demineralization, or processed by both laser perforation and partial demineralization. Only two recipient animals showed a transient, antibody-mediated donor-specific immune response. One of these animals had received a control allograft, whereas the other animal had received a laser-perforated and partially demineralized bone allograft. All of the grafts in this study, including control grafts, were stripped of soft tissues and their bone marrow was removed; cellular sources of alloantibody stimulation may have been eliminated by these processes. The results of this study suggest that immune responses to bone allografts may be reduced by removing the bone marrow and adjacent soft tissues. The processing of cortical bone allografts by laser perforation and partial demineralization appeared to have little effect on immune responses.

Animals↗
PubMed2001

The determination of ketone bodies: preanalytical, analytical and physiological considerations.

The arterial ketone body ratio is calculated as the ratio of arterial levels of acetoacetate/beta-hydroxybutyrate. It correlates with survival in experimental hemorrhagic shock and outcome after liver surgery and myocardial infarction. Procedures for determination of ketone bodies are often laborious and unreliable. As yet the relationship between results from arterial and venous samples is unclear. We therefore describe the determination of the ketone bodies acetoacetate and 3-hydroxybutyrate by an easy, reliable, rapid, inexpensive enzymatic assay using 3-hydroxybutyrate dehydrogenase (E.C. 1.1.1.30) in a semi-automated setting that does not require deproteinization. Preanalytical parameters, including separation from corpuscular elements within 1 h and storage on ice for less than 1 h, must be strictly observed to avoid rapid decay of acetoacetate by spontaneous decarboxylation. The assay has high sensitivity, specificity (+/-5%), and precision (CV <2.5%) with a measurable range of 5-500 micromol/l for either ketone body, and requires only 23.5 microl of plasma. At temperatures below -17 degrees C plasma may be stored for prolonged periods. Results from prospectively scheduled simultaneous sampling of arterial blood and venous blood from the right atrium in 100 consecutive patients with severe multiple trauma (mean Injury Severity Score 38+/-13) support the view that the lung has no role in ketone body metabolism. We conclude that central venous blood can safely be substituted for arterial blood for determination of the ketone body ratio.

3-Hydroxybutyric Acid↗
PubMed2001

Systematic review and meta-analysis of antibiotic therapy for bone and joint infections.

We set out to evaluate the clinical efficacy of individual antibiotic agents for bone and joint infections in adults. Published and unpublished controlled trials reported between 1966 and 2000 were reviewed to determine if they involved random or quasi-random allocation to systemically administered antimicrobials or local antibiotic therapy for osteomyelitis and septic arthritis. Quiescence of infection after 1 year of follow-up was defined as the primary outcome measure. 22 trials containing 927 patients were eligible for final analysis. Varying proportions of the entire study population could be evaluated with respect to primary and secondary endpoints. Methodological quality was poor among most studies, and interpretability of results was further limited by small sample sizes, missing descriptions of patient populations and disease characteristics, and the frequent application of concomitant antibiotics. A trend towards improved, long-lasting infection control was observed in favour of a rifampicin-ciprofloxacin combination versus ciprofloxacin monotherapy for the treatment of staphylococcal infections related to orthopaedic devices (absolute risk difference [ARD] 28-9%; 95% CI -0.7 to 54.4%). Obviously unbalanced comparative studies showed some benefit of ticarcillin for bone infections caused by Pseudomonas species. No significant differences in therapeutic efficacy were found among trials comparing oral fluoroquinolones with intravenous beta-lactam drugs for both end-of-treatment (OR 0.8; 0.5 to 1.4) and long-term results (OR 1.3; 0.8 to 2.1). A variety of drugs was used as controls, thereby leading to inconsistent findings of drug-related side effects. Only one randomised trial was suitable to investigate the impact of polymethylmethacrylate gentamicin bead chains compared with parenteral antibiotics for skeletal infections, although this study was biased by patients receiving both combined local and systemic antibiotic therapy. Whereas intention-to-treat evaluation suggested a therapeutic advantage of systemic over local therapy, this trend diminished in the per-protocol analysis (1-year follow-up ARD -2.3;-17.5 to 10.8%). There exists little high-quality evidence on antibiotic therapy for osteomyelitis and septic arthritis. The observed heterogeneity among patient populations and medical and surgical treatment concepts preclude reliable inferences from the available data.

Anti-Bacterial Agents↗
PubMed2001

Systematic review and meta-analysis of emergency ultrasonography for blunt abdominal trauma.

BACKGROUND: How precise and reliable is ultrasonography as a primary tool for injury assessment in blunt abdominal trauma? METHODS: A systematic review and meta-analysis were conducted of prospective clinical trials of ultrasonography for blunt abdominal trauma. Publications were retrieved by structured searching among databases, review articles and major text books. Authors and experts in the field were contacted for original and unpublished data. For statistical analysis, summary receiver operating characteristic curves (SROCs) were computed using weighted and robust regression models, with Q* denoting the shoulder of the curve. Post-test probabilities were calculated as a function of pooled likelihood ratios (LRs). RESULTS: Thirty of 123 trials enrolling 9047 patients were eligible for final analysis. With respect to targeting organ lesions, ultrasonography showed a summary Q* value of 0.91 (inverse variance weights, 95 per cent confidence interval (c.i.) 0.76-1.07); negative predictive values ranged from 0.72 to 0.99. A similar SROC slope was calculated for screening for free fluid (Q* = 0.89 (95 per cent c.i. 0.73-1.05)). Ultrasonography detects the presence of organ lesions, but fails to exclude abdominal injuries (random effects negative LR 0.23 (95 per cent c.i. 0.18-0.28)). Given a pretest probability of 50 per cent for blunt abdominal injury, a post-test probability of nearly 25 per cent remains in the case of a negative sonogram. CONCLUSION: Despite its high specificity, ultrasonography has an unexpectedly low sensitivity for the detection of both free fluid and organ lesions. In clinically suspected abdominal trauma, another assessment (e.g. helical computed tomography) must be performed regardless of the initial ultrasonographic findings.

Abdominal Injuries↗
PubMed2001

[Early death of the severly injured patient--A retrospective analysis].

With 44.9 % trauma is the main cause of death in men under 40 years. From September 3(rd) 1997 to June 30(th) 1998 174 patients with severe injuries or polytrauma were treated in our hospital. The mean ISS was 29 (18-75). 15 (8.75 %) patients died within the first 24 hours. The mean age was 34.5 (2-85) years. The mean ISS of these patients was 48 (25-75). In a retrospective study we analyzed the pattern of injury as well as the preclinical and clinical management. The fact that orthopedic surgery still has got a poor position within the patient's satisfaction-scale and that 15 of 174 analyzed patients had to die within the first 24 hours points out the importance of internal and external quality improvement measurements.

Adolescent↗
PubMed2001

The stabilizing effects of different orthoses in the intact and unstable upper cervical spine: a cadaver study.

BACKGROUND: Although cervical orthoses are frequently used in prehospital stabilization and in the definitive treatment for lesions of the cervical spine, there is little information about the control of extension-flexion, lateral bending, and rotation given to individual segments by different designs. METHODS: In an experimental in vitro study with four fresh frozen cadavers, the halo vest was compared with the soft collar, prefabricated Minerva brace, and Miami J collar. The controlling effects for the segments C1-2 and C2-3 were tested for all four devices in the intact and the unstable spine with an Anderson type II fracture of the odontoid. RESULTS: All four orthoses reduced the range of motion at both C1-2 and C2-3 of the intact spine significantly, although none of the three semirigid devices provided a halo-like immobilization in the intact spine. The osteotomy of the odontoid increased the range of motion in the segment C1-2. The soft collar did not give any clinically relevant stability to the unstable spine. Miami J and Minerva brace provided a similar moderate control in the sagittal plane but a much better control of "torque" in the upper cervical spine. The halo vest did not allow any measurable motion in any plane with our experimental external loading. CONCLUSION: The halo vest seems to be the first choice for conservative treatment of unstable injuries of the upper cervical spine, although pin track problems, accurate fitting of the vest, and a lack of patient compliance lead to clinical failures.

Biomechanical Phenomena↗
PubMed2001

Discriminatory power of 3.5 MHz convex and 7.5 MHz linear ultrasound probes for the imaging of traumatic splenic lesions: a feasibility study.

BACKGROUND: Ultrasound is a powerful tool for recognition of free fluid after blunt abdominal trauma, whereas its role for detection of organ lesions remains to be defined. The objective of this study was to determine the diagnostic value of different ultrasound transducers for the precise detection of visceral damage rather than its surrogates in case of splenic injury. METHODS: After a standardized focused abdominal sonogram for trauma protocol to screen for hemoperitoneum, 37 slim, hemodynamically stable subjects with suspected torso trauma were investigated for the extent of parenchymal lesions of the spleen using a 3.5 MHz curved array and a 7.5 MHz linear device. Helical computed tomographic scanning was carried out as the reference standard in all cases. RESULTS: Twenty patients presented splenic damage. The 7.5 MHz transducer showed higher accuracy than the lower frequency probe for the detection of tissue irregularities (difference in proportions, 16.2%; 95% confidence interval, -1.9%-33.5%). A similar trend was observed for 13 lacerations subsequently progressing to two-timed splenic rupture that required surgery (absolute risk reduction, 8.1%; 95% confidence interval, -7.6%-23.9%). With an observed prevalence of 54% for the presence of splenic injury, organ lacerations could be excluded more confidently using the linear probe (posttest probability, 16% vs. 36%). CONCLUSION: In slim patients, higher frequency linear ultrasound probes can provide therapy-relevant information on the integrity of splenic parenchyma after blunt abdominal trauma.

Abdominal Injuries↗
PubMed2001

[Computer-assisted, robot-assisted hip prosthesis--standard procedure or specialty indication?].

Approximately 150,000 total hip replacements annually are performed in Germany, with an increasing incidence of implants carried out on young subjects. Due to aseptic loosening, this group will undergo some revision arthroplasty after 15 years. Therefore, a permanent fixation appears mandatory. In case of posttraumatic or postoperative anatomical changes, exact preoperative planning by x-rays is extremely difficult. This might result in a higher rate of complications (e.g., displacement of the implanted prosthesis, fractures of the proximal femur), as documented by the available literature. The preoperative planning with CT images obtained at the 3D workstation shows the exact cortical situation, while the robot-assisted surgery allows the precise execution of the preoperative plan during surgery. By this point of time, long-term results of computer-guided, robot-assisted implantation of endoprosthesic devices are still lacking. However, the preliminary data indicate good results by means of anatomical position of the endoprosthesis and perioperative complications.

Arthroplasty, Replacement, Hip↗