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S Sauerland

Publications and source records attributed to S Sauerland.

At least 55 records · Page 3Linked to original sources

Retrospective clinical studies in surgery: potentials and pitfalls.

As many surgical studies are performed retrospectively, it is desirable to improve the conduct, analysis and reporting of such research designs. This article reviews some of the most common forms of bias encountered in clinical research and outlines various types of study design and analysis that can help to minimize the amount of bias introduced into the results. We describe the advantages and disadvantages of 'raw' data analysis, stratified analysis, matched pair analysis and multivariate analysis, and apply them to an example of a hypothetical hand surgery study.

Controlled Clinical Trials as Topic↗

[The role of preoperative oesophageal manometry in patients with gastro-oesophageal reflux disease].

BACKGROUND: Oesophageal manometry has become a standard investigation in the management of functional disorders of the oesophagus. However, the importance of the various manometry parameters for the surgical management of patients with gastro-oesophageal reflux disease (GERD) has not yet been studied adequately. AIM: This study examined the importance of manometric findings on surgical treatment results in patients with GERD. PATIENTS AND METHODS: Between January 1995 and January 2000, 123 consecutively referred patients with GERD symptoms were studied. Ninety-seven of these (52 women and 45 men, mean age 48 years) underwent Nissen fundoplication in conventional or laparoscopic technique. Preoperatively, each patient received stationary oesophageal manometry with a water perfusion catheter, gastroduodenoscopy and 24h-pH-metry of the oesophagus. Independent of manometric results, patients received 360 degrees fundoplicatio with 2 cm cuff ("floppy Nissen"). RESULTS: Eighty-five of the 97 patients (88 %) had an incompetent lower oesophageal sphincter. Hypomotility was diagnosed in 17 (18 %). Amotile achalasia and diffuse oesophageal spasms were seen in two and one patient, respectively, who were not operated on. Follow-up data were available for 92 % of patients (mean follow-up time 1.8 years). Five and 8 patients (1 and 2 of these with hypomotility) postoperatively developed persistent dysphagia and GERD recurrence, respectively (relative risks 1.2 and 1.6). Two patients (one with hypomotility) required surgical revision. CONCLUSIONS: Preoperative oesophageal manometry in GERD patients is useful only for determining the position of the upper boundary of the lower oesophageal sphincter and for ruling out specific motility disorders. In patients with oesophageal hypomotility, "floppy Nissen" fundoplicatio can be performed without an excess risk of dysphagia.

Deglutition Disorders↗

[Incisional hernia repair in Germany at the crossroads: a comparison of two hospital surveys in 1995 and 2001].

INTRODUCTION: Incisional hernia repair has become a controversial issue in surgery. METHODS: To survey the current practice patterns of incisional hernia repair, a questionnaire was mailed to 2 380 surgical departments in Germany. Responses were received from 732 hospitals. The results of the current survey were compared with that of a similar survey performed in 1995. RESULTS: Overall, the incidence of incisional hernia surgery seems to have markedly increased. An increasing number of operations is performed in specialized large centres. Depending on hernia type (primary hernia < 5 cm, primary hernia > 5 cm, recurrent hernia) mesh materials have gained popularity (15 %, 67 %, and 79 %, respectively) as compared to 1995. Prolene(R) (34 %) and Vypro(R) (25 %) are the currently preferred meshes. The number of hospitals that use non-resorbable suturing material has doubled between 1995 (22 %) and 2001 (45 %). Interrupted suture are no longer the standard technique for fascia closure (80 % in 1995, 50 % in 2001). Autodermal skin graft and laparoscopic hernia repair are of little importance. Although literature data suggest high recurrence rates, most surgeons still expect that only 5-10 % of their primary or recurrent hernia repairs will fail. CONCLUSIONS: Incisional hernia repair is undergoing radical changes. However, it is unclear whether these changes in surgical techniques and materials were caused by the individual surgeon's clinical expertise, the recent publication of important trials, or the financial circumstances.

Cicatrix↗

The European Association for Endoscopic Surgery clinical practice guideline on the pneumoperitoneum for laparoscopic surgery.

BACKGROUND: The pneumoperitoneum is the crucial element in laparoscopic surgery. Different clinical problems are associated with this procedure, which has led to various modifications of the technique. The aim of this guideline is to define the scientifically proven standards of the pneumoperitoneum. METHODS: Based on systematic literature searches (Medline, Embase, and Cochrane), an expert panel consensually formulated clinical recommendations, which were graded according to the strength of available literature evidence. RECOMMENDATIONS: Preoperatively, all patients should be assessed for the presence of cardiac, pulmonary, hepatic, renal, or vascular comorbidity. Presupposing appropriate perioperative measures and surgical technique, there is no reason to contraindicate pneumoperitoneum in patients with peritonitis or intraabdominal malignancy. During laparoscopy, monitoring of end tidal CO2 concentration is mandatory. The available data on closed- (Veress needle) and open-access techniques do not allow us to principally favor the use of either technique. Using 2 to 5-mm instead of 5 to 10-mm trocars improves cosmetic result and postoperative pain marginally. It is recommended to use the lowest intraabdominal pressure allowing adequate exposure of the operative field, rather than using a routine pressure. In patients with limited cardiac, pulmonary, or renal function, abdominal wall lifting combined with low-pressure pneumoperitoneum might be an alternative. Abdominal wall lifting devices have no clinically relevant advantages compared to low-pressure (5-7 mmHg) pneumoperitoneum. In patients with cardiopulmonary diseases, intra- and postoperative arterial blood gas monitoring is recommended. The clinical benefits of warmed, humidified insufflation gas are minor and contradictory. Intraoperative sequential intermittent pneumatic compression of the lower extremities is recommended for all prolonged laparoscopic procedures. For the prevention of postoperative pain a wide range of treatment options exists. Although all these options seem to reduce pain, the data currently do not justify a general recommendation.

Contraindications↗

Classification and surgical treatment of incisional hernia. Results of an experts' meeting.

BACKGROUND: The treatment of incisional hernia (IH) is a current problem in modern surgery. Many important aspects of incisional hernia surgery are yet to be answered, especially the choice of surgical technique and its adaptation to the individual patient. The aim of this experts' meeting was to resolve some current questions in incisional hernia surgery and to organise an international hernia register. METHODS: An international panel of ten experts met under the auspices of the European Hernia Society (GREPA) to investigate the classification and therapeutic alternatives for incisional hernia. Prior to the conference, all experts were asked to submit their arguments in the form of published results. All papers received were weighted according to their scientific quality and relevance. The information from this correspondence was used as a basis for panel discussion. The personal experiences of the participants and other aspects of individualised therapy were also considered. RESULTS: The expert panel suggested a new classification of incisional hernia based on localisation, size, recurrences and symptoms. All experts agreed that the fascia duplication and the fascia adaptation should only be used for small incisional hernias. Fascia duplication is of value only in the horizontal direction. The technical details and the pros and cons of each procedure were discussed for prosthetic implantation using onlay and sublay techniques and the technique of autodermal hernioplasty. CONCLUSIONS: The management of incisional hernia is currently not standardised. In order to answer relevant questions of incisional hernia surgery, an international hernia register should be established.

Hernia, Ventral↗

A pig hemorrhagic shock model: oxygen debt and metabolic acidemia as indicators of severity.

"Uncontrolled bleeding," "a controlled prefixed bleeding volume," or "controlled decrements in blood pressure" are traditional models of experimental hemorrhagic shock. They are influenced by compensatory mechanisms and do not adequately reflect the severity of the cellular insult as a major target for therapeutic strategies. The aim of this study was to develop an animal model that uses oxygen debt (OD) and metabolic acidemia as indicators of hemorrhage severity. Twenty-five female pigs (mean weight: 23.8 kg) were anesthesized and randomized to 1 of 5 groups of increasing OD (<50 through >120 mL/kg). The predetermined OD was accrued by hemorrhage uniformly over 60 min and followed by retransfusion. The animals were allowed to recover under anesthesia for 200 min and were then observed for 3 days. The extent of metabolic derangements were quantified by arterial base excess (BE) and plasma lactate (LAC) measurements. OD, BE, and LAC were shown to be superior as predictors of outcome in comparison with traditional variables ("bleeding volume," "blood pressure," "cardiac output") in correlation and regression. Of the analyzed predictors of outcome, BE and LAC showed the highest correlation to levels of OD (r = -0.78, 0.8 respectively; P < 0.0001), and regression models were developed. The LD50 for OD was 95.0 mL/kg, for BE -15.3 mmol/L and for LAC 7.7 mmol/L. By using the developed regression models, it is possible to estimate accurately the actual level of OD from BE and LAC values obtained during hemorrhagic shock. OD, BE, and LAC appear to be optimal indicators of severity for a pig hemorrhagic shock model.

Animals↗

Complexity and non-linearity in shock research: reductionism or synthesis?

The various analytical techniques used to explain the many supposed mediators of sepsis and septic shock have outpaced the integrative approaches that simplify this complexity for the physiologist and the clinician. In this article we discuss the pros and cons of reductionism and its limitations in the field of shock research and emphasize the need for synthesis research. Taking account of the historical development of natural science, we will discuss the question of how far a reductionist approach can help to explain biological phenomena and conclude that reductionism, although essential to the scientific process, reduces the evidence absurdity if exaggerated. The part is never the whole, and it is impossible to understand the whole through limited dissections of its parts. The understanding of complex systems requires approaches other than those of explanatory reductionism. We emphasize a different approach-systems thinking. Systems scientists are not interested in the underlying components; they describe and characterize complex relations. Other disciplines that use systems thinking should be studied. However, to follow the concept of synthesis, reductionists must describe the components of the system. Reductionism and synthesis are therefore the two sides of a coin. Professional synthesis research is a serious challenge in shock research.

Animals↗

The effect of additional brain injury on systemic interleukin (IL)-10 and IL-13 levels in trauma patients.

OBJECTIVE: Besides interleukin (IL)-10, accumulating evidence from in vitro studies has indicated a strong antiinflammatory capacity for IL-13. A prospective clinical study was undertaken to assess the influence of additional brain injury on systemic IL-10 and IL-13 levels as markers for the antiinflammatory state in trauma patients. MATERIAL AND METHODS: The course of IL-10 and IL-13 plasma levels from 32 patients with an isolated severe head trauma (SHT), 50 patients with multiple injuries and additional SHT and 39 patients with multiple injuries without SHT was detected using ELISA-technique. Blood samples from 37 healthy blood donors were analysed for control. RESULTS: IL-10 levels were significantly elevated in all 3 injury groups within 3 h after trauma. The lowest initial release was detected in patients with an isolated SHT (Injury severity score; ISS: 18.1 +/- 5.6). No difference could be demonstrated for the IL-10 levels from multiple injured patients with (ISS: 35.3 +/- 9.6) or without additional SHT (ISS: 25.5 +/- 11.7), though there were relevant differences in the ISS. In contrast, the IL-13 plasma levels were not elevated systemically after trauma. CONCLUSIONS: IL-10 but not IL-13 is a detectable antiinflammatory marker in trauma patients with or without brain injury and to a minor degree in patients with an isolated SHT.

Adult↗

Laparoscopic fundoplication for gastro-oesophageal reflux disease - a consensus development conference and the evidence-based benefit.

The aim of this paper is to demonstrate an example of evidence-based medicine for a clinically relevant and frequent disease - gastro-oesophageal reflux disease - for which an increasing number of laparoscopic operations is performed. A consensus development conference was performed on this topic in 1996. During the following 3-year period, increase of knowledge shown by the number of publications was monitored and the consecutive changes of the consensus as well as its consequences and impact were analysed. The six published randomised clinical trials revealed important information about the technique of the laparoscopic operation focussing on the gastric fundic mobilisation and the modification of the anti-reflux wrap. Five consecutive consensus conferences were performed and published. Citations of the 1996 consensus conference could not be found in the major surgical journals - not even by participants of the conference. The responsibility of societies to run such conferences continues.

Consensus Statements as Topic↗

Consensus conferences must include a systematic search and categorization of the evidence.

BACKGROUND: Ideally, a consensus panel combines expert knowledge with external evidence derived from the literature. To date, many consensus conferences do not use a structured approach to search the literature, but simply compile an add-on reference list from all papers cited by the panelists. This study examined how well such panelists retrieved the relevant literature. METHODS: We used the reference lists of nine surgeons who took part in a consensus conference on common bile duct stones. We included all papers that were referred to as randomized controlled trials (RCTs). We then compared this list with a database search in order to calculate sensitivity and specificity. RESULTS: The nine experts cited between 35 and 518 papers, but only eight papers on average were RCTs. Of the 49 papers that the experts believed to be RCTs, only 23 actually were RCTs. The sensitivity resp. specificity for correctly identifying an RCT was 0.21 (95% Cl, 0.11-0.30) resp. 0.80 (95% Cl; 0.64-0.95). RCTs that included the word "randomized" in their title were significantly more likely to be identified (relative risk, 1.31; 95% Cl, 1.18-1.45). CONCLUSION: Our data indicate that consensus panelists usually do not perform systematic literature searches, but simply use their favorite papers to back up their arguments. Because this may lead to a biased selection of the evidence base on which the consensus statements are founded, a systematic search of all relevant articles should become a mandatory task in any consensus or guideline process.

Consensus Statements as Topic↗

Serum uric acid and patterns of radiographic osteoarthritis--the Ulm Osteoarthritis Study.

OBJECTIVE: To assess the association between uric acid and patterns of osteoarthritis (OA). METHODS: OA patterns were studied in 809 patients with arthroplasty due to hip or knee OA. Patients with OA were categorized as having bilateral or generalized OA according to the presence of radiographic OA in the contralateral or different finger joints. Odds ratios (OR) and 95% confidence intervals (CI) for thirds of serum uric acid and OA patterns were estimated with multivariable logistic regression. RESULTS: Eighty-five percent of the participants had bilateral OA and 26% generalized OA. A positive association between serum uric acid and generalized OA was observed in patients with hip OA (highest versus lowest tertile OR=3.5; 95% CI: 1.3-9.1), but not among patients with knee OA (corresponding OR = 1.1). Serum uric acid was not associated with bilateral OA. CONCLUSION: Our results suggest a possible role of elevated serum uric acid in the multifactorial etiology of generalized OA.

Aged↗

Risks and benefits of preoperative high dose methylprednisolone in surgical patients: a systematic review.

BACKGROUND: A single preoperative high dose of methylprednisolone (15 to 30 mg/kg) has been advocated in surgery, because it may inhibit the surgical stress response and thereby improve postoperative outcome and convalescence. However, these potential clinical benefits must be weighed against possible adverse effects. OBJECTIVE: To conduct a risk-benefit analysis using a meta-analysis, to compare complication rates and clinical advantages associated with the use of high dose methylprednisolone in surgical patients. METHODS: Randomised controlled trials of high dose methylprednisolone in elective and trauma surgery were systematically searched for in various literature databases. Outcome data on adverse effects, postoperative pain and hospital stay were extracted and statistically pooled in fixed-effects meta-analyses. RESULTS: We located 51 studies in elective cardiac and noncardiac surgery, as well as traumatology. Pooled data failed to show any significant increase in complication rates. In patients treated with corticosteroids, nonsignificantly more gastrointestinal bleeding and wound complications were observed; the 95% confidence interval boundaries of the numbers-needed-to-harm were 59 and 38, respectively. The only significant finding was a reduction of pulmonary complications (risk difference -3.5%; 95% confidence interval -1.0 to -6.1), mainly in trauma patients. CONCLUSION: For patients undergoing surgical procedures, a perioperative single-shot administration of high dose methylprednisolone is not associated with a significant increase in the incidence of adverse effects. In patients with multiple fractures, limited evidence suggests promising benefits of glucocorticoids on pulmonary complications.

Animals↗

The pros and cons of evidence-based surgery.

INTRODUCTION: Evidence-based medicine (EBM) has been proposed as a new paradigm of practising medicine. However, an unproductive polarisation between supporters and opponents can make its unbiased assessment difficult. This review gives an overview of the arguments and discusses their surgeon-specific importance. DISCUSSION: As EBM claims a position in the centre of medicine, it borders with other highly debated topics as, for instance, rationing and equity of care, doctor-patient interaction, medical research and education. Most arguments against EBM relate to its role in reducing health expenses by rationing healthcare. We think that the principles of EBM can be applied to make the inevitable process of rationing fair and reproducible. In addition, evidence-based surgery is criticised for interfering with patient individuality and physician autonomy, although this is a misunderstanding. Furthermore, the evidence-basis of EBM, in particular the randomised controlled trial (RCT) and systematic review, has been subject of discussion. Additionally, surgical research has its own inherent difficulties and, ultimately, some clinicians have doubted the practical feasibility of applying EBM at the bedside, because searching and critically appraising the literature is too difficult and time consuming. CONCLUSIONS: We believe that most critics consider EBM to be a potentially dangerous tool, because they fear it will be used against themselves. Thus, these conflicts only prove that EBM as a methodology may have a strong impact on solving them. As EBM has already made discernible progress, surgeons should not stand aside from these activities, which are bound to strongly influence healthcare in the next century.

Humans↗

Diagnosis and treatment of diverticular disease: results of a consensus development conference. The Scientific Committee of the European Association for Endoscopic Surgery.

BACKGROUND: With the aim of resolving the current controversy over the diagnosis and treatment of diverticular disease, this consensus development conference set out to summarize the actual state of the art. METHODS: A multidisciplinary panel of international experts (n = 16) was selected to take part in the consensus process. Prior to the conference, all experts were asked to answer a series of questions on diverticular disease. The consensus statement compiled out of these evaluations was modified during a joint meeting of the panel members, then presented for discussion in a public session, and finally revised by the expert panel. The finalized statement was mailed to all panel members for approval (Delphi method). RESULTS: Asymptomatic diverticulosis, diverticular disease (with actual or recurrent symptoms), and complicated diverticular disease were defined separately. No agreement was reached on whether barium enema or colonoscopy is the better choice as an initial diagnostic tool in uncomplicated cases. In complicated cases, computed tomography is recommended for diagnosis. After two attacks of diverticular disease, elective resection should be considered. For patients in whom a concomitant carcinoma cannot be excluded and those with chronic complications (fistula, stenosis, or bleeding) surgery is also indicated. Laparoscopic sigmoid colectomy is recommended only for uncomplicated and, after percutaneous drainage of abscesses, Hinchey stage I and II cases. CONCLUSIONS: Laparoscopic surgery has already begun to influence the management of diverticular disease, but the randomized controlled trials needed to support therapy decisions are largely missing.

Diverticulitis↗

[The status of perioperative pain therapy in Germany. Results of a representative, anonymous survey of 1,000 surgical clinic. Pain Study Group].

To evaluate the status of perioperative pain management we mailed a anonymous postal survey to all 2,254 surgical departments in Germany. We received answers from 1,000 clinics (44.4%) which were representative related to their regional distribution. We asked the responsible surgeons to report their organizational structure and responsibilities for treating pain patients, the significance of the problem, their methods of measuring pain, and the usage of different analgesic drugs and methods. In 47% the surgeon and the anesthesist together had responsibility for adequate postoperative pain treatment; in 33% and 14%, respectively, it was the surgeon and anesthesist alone. Only 41% knew the interdisciplinary statement on pain therapy of the Professional Societies of German Surgeons and Anaesthesists from 1992. Although the importance of postoperative pain is globally acknowledged, only 19.1% of all departments had a written concept for pain treatment. Pain was measured in only 11% of the clinics mainly by using the visual analogue scale. Most surgeons relieve pain solely with systemic drugs. Regional analgesia was used by 18% only 51% of the surgeons decide on the choice and dosage of analgesic therapy on the ward; 33% admit that pain therapy often starts after complaints of the patient. 70% of all surgeons never participated in a congress on pain. We conclude that postoperative pain management in most German surgical departments still lacks effectiveness, adequacy, and organizational and scientific background.

Analgesics↗

Laparoscopic vs conventional appendectomy--a meta-analysis of randomised controlled trials.

AIM: To compare the effectiveness and safety of laparoscopic and conventional "open" appendectomy in the treatment of acute appendicitis. METHODS: Meta-analysis of randomised controlled trials available by May 1998 that compared both techniques. Within each trial and for each outcome an effect size was calculated; the effect sizes were then pooled by a random-effects model. RESULTS: We summarised outcome data of 2877 patients included in 28 trials. Operating time was +16 min (95% confidence interval +12-20 min) longer for laparoscopic appendectomy. Overall complication rates were comparable, but wound infections were definitely reduced after laparoscopy [rate difference -4.2%, (-2.3% to -6.1%)]. Intra-abdominal abscesses, however, occurred slightly more frequently [+0.9%, (-0.4% to +2.3%)]. Hospital stay after laparoscopic appendectomy was 15 h (8-23 h) shorter, and patients returned to full fitness or work 7 days (5-9 days) earlier. Pain intensity on day 1 was slightly less. Heterogeneity was present for some outcome measures due to methodological differences among the primary studies. CONCLUSION: Laparoscopic appendectomy reduces wound infections and eases postoperative recovery. Nevertheless, the various differences among the primary studies and their partly flawed methodology make it difficult to generalise from these findings.

Acute Disease↗