Thomas Bohrer

Clinical Decision-making, Ultrasonography, and Scores for Evaluation of Suspected Acute Appendicitis

Abstract. Diagnosing acute appendicitis (aA) remains difficult. This study evaluated the utility of ultrasonography (US) compared to clinical decision-making alone and scoring systems to establish the indication for laparotomy in patients in whom aA was suspected. The prospectively documented data of 2209 patients admitted for suspicion of aA, who underwent US by one of 12 surgeons, formed a database in which the diagnostic and procedural performance of clinical decision-making, US, two scoring systems (Ohmann and Eskelinen scores), and clinical algorithms taking account of clinical and either US findings or score results, were retrospectively evaluated. The results of either modality were correlated with final diagnoses obtained by laparotomy in 696 patients, of whom 540 had aA (prevalence 24.45%) and follow-up data in the remainder. US had the highest specificity (97%, compared to 93% for the Ohmann and Eskelinen scores and 94% for the clinical evaluation and algorithms) and lowest overall rate of false-positive findings (negative laparotomy rate 7.6%). The scores were accurate in refuting the diagnosis of aA but otherwise not superior to US. The best overall diagnostic and procedural results were obtained with the algorithms that combined the results of either US or the Ohmann score with clinical evaluation, which produced the most favorable numbers of negative laparotomies, potential perforations, and missed cases of aA. US is the diagnostic standard of reference for patients with a possible diagnosis of aA. It yields diagnostic results superior to those of scoring systems and provisional clinical evaluation. However, the benefits of US by ultrasonographically trained surgeons are only fully appreciated within the context of clinical algorithms. The joint evaluation of score results and clinical evaluation may deliver information of similar accuracy.

Parathyroid Xenotransplantation without Immunosuppression in Experimental Hypoparathyroidism: Long-term In Vivo Function following Microencapsulation with a Clinically Suitable Alginate

Permanent hypoparthyroidism is one of the most difficult of all endocrine disorders to treat medically. Because this deficiency syndrome rarely is a life-threatening condition, systemic immunosuppression for recipients of transgenic transplants is not justified. An alternative would be protecting the tissue to be transplanted from the immunologic response (immunoisolation) by coating it with a semipermeable membrane- microencapsulation. Unfortunately, prior to the first clinical use, further analysis of the coating substance (alginate) demonstrated that it has potential cancerogenic properties. Using a purified amitogenic alginate suitable for clinical use, we accomplished allotransplantation in a long-term animal model and reported the first clinical cases without postoperative immunosuppression recently. In view of the potential clinical use, we investigated the ability of the microencapsulation technology with the novel amitogenic alginate in experimental hypoparathyroidism (80 parathyroidectomized rats) to enable transgenic transplantation across the highest immunologic barrier (xenotransplantation: human to rat) to ensure intact transplant function without immunosuppression. In a controlled, long-term animal study, the effect of microencapsulation on xenotransplanted human parathyroid tissue was evaluated over a period of 30 weeks (microencapsulated and naked hyperplastic parathyroid tissue, respectively). Functionally, human parathyroid tissue was able to replace that of rats. More than 6 months after xenotransplantation 32 of 40 animals that had received microencapsulated transplants were normocalcemic. In contrast, serum calcium concentrations dropped to postparathyroidectomy levels within 3 weeks in the animals that had received naked tissue only. Correspondingly, normocalcemic animals showed vital parathyroid tissue inside the microcapsules, which were surrounded by a small rim of fibroblasts. When combining microencapsulation with an improved tissue culture method, xenotransplantation of human parathyroid tissue and maintenance of its physiologic function is reproducibly achieved over the highest transplantation barrier. Using the amitogenic alginate may be a crucial step toward the first clinical use of this technique for parathyroid xenotransplantation without immunosuppression.

Feasibility of MRI in the diagnosis of acute diverticulitis: initial results

Purpose: The purpose of this study was to evaluate MRI as a diagnostic tool in patients with suspected acute sigmoid diverticulitis. Furthermore, we sought to develop an optimal imaging protocol in these patients.Patients and methods: Eleven patients with suspected acute diverticulitis were included in the study. All patients were imaged in a 1.0 T clinical scanner using a body-array coil. Imaging sequences were single-shot TSE, HASTE-, STIR- and TrueFisp-sequence. All were obtained in the frontal plane. The diagnosis was verified by a single experienced investigator, using ultrasound, and overall clinicopathological outcome.Results: MRI enabled visualization of signs of an acute diverticulitis in all patients. However, the diagnosis of acute diverticulitis was obtained in 10 patients only. The mean imaging time was 17.5 ± 5.5 min. STIR- and TrueFisp-sequences alone displayed all findings, e.g pericolonic exsudation, edema and segmental narrowing, whereas SSTSE and HASTE-sequences showed no additional information. Therefore, it appeared that the imaging protocol could be restricted to STIR- and TrueFisp-sequences.Conclusion: MRI is feasible as a fast, accurate and investigator-independent diagnostic tool in patients with suspected acute diverticulitis. To prove its value in comparison to computed tomography or ultrasound, further studies are needed.

A clinical chameleon: postoperative hypoparathyroidism

BackgroundAbout 1,200 patients per year develop postoperative hypoparathyroidism alone in Germany. Many of those patients may be misdiagnosed as the symptoms of this disease may vary and can be atypical.Patient/resultsAs an example, we describe the first known case of an elderly patient with a long history of seizures as a complication of an undiagnosed chronic hypoparathyroidism after surgery of a pT4-esophageal carcinoma. The 63-year-old male patient underwent laryngo–hypopharyngo–esophagectomy with gastric transposition and partial thyroid resection for a proximal esophageal carcinoma in 1994. About half a year later, the patient developed for the first time a convulsive syncope. Misleading diagnoses were for years suspected metastasis formation and a dumping syndrome. The general physician of the patient called him the epilepsy man, while no cause of the seizures were found. More than a decade of years later, when the correct diagnosis was made, finally by determination of parathyroid hormone levels, the seizures of the patient were completely eliminated by calcium supplementation therapy. The patient’s quality of life improved clearly in the following time.ConclusionIt is essential to consider chronic hypoparathyroidism in the differential diagnosis of patients with hypocalcemia who have undergone extended neck and proximal esophageal surgery before. In addition to that, it is mandatory to autotransplant parathyroids during the initial procedure which might be accidentally removed during surgery and to monitor parathyroid function in each patient in the further course postoperatively.

Optimierung der Sauerstoffversorgung von Mikrokapseln zur transgenen Transplantation der Parathyreoidea durch Perfluorokarbon (FC 43)

Background: At least 1000 new patients per annum suffer from permanent hypoparathyroidism in Germany alone, generally caused by thyroid surgery. The need for transgenic transplantation of parathyroid tissue (PT) is undisputed. In this study it was tested whether perfluorocarbone (FC 43) increases as additive the oxygen supply and stability of microcapsules containing PT, as the first results in islet cell transplantation have indicated before. Methods: Hyperplastic PT was cut into 144, ca. 2-mm3 large particles and underwent a tissue culture passage. After 3 days, 48 of these particles were microencapsulated without and with FC 43, respectively, in highly purified alginate microspheres. A total of 48 native PT particles formed the control group. Every 4 days the stability of the capsules was controlled by a standardized test. The function of the encapsulated PT was evaluated by the measurement of the PTH release every 4 days and the vitality of PT was determined by histological evaluation (H&E staining). The duration of the study was 32 days for all measurements. Results: The diameters of microcapsules without and with FC 43 remained nearly constant with 2.26±0.09 and 2.21±0.12 mm. PTH release was in the median 2068.14 pg/ml (initially: 3249.52 pg/ml) for microcapsules without FC 43 and 3051.17 pg/ml (initially: 2814.54 pg/ml) for microcapsules containing FC 43 and 67.1 pg/ml (initially: 2698.53 pg/ml) for native PT particles after 32 days. Histologically, PT of microcapsules without FC 43 showed a vitality of 45% after 32 days, whereas PT encapsulated with FC 43 had a vitality of 55%. Native PT particles already developed total necrosis after 8 days. Conclusions: These results clearly indicate the importance of the biophysical properties of alginate material for the microencapsulated transplants. FC 43 significantly improves in vitro the nutritive supply of encapsulated PT followed by increased function while maintaining constant stability of the microspheres.

Postoperative sternale Wundheilungsstörungen im Alter

ZusammenfassungHintergrundPostoperative sternale Wundkomplikationen, wie Sternuminstabilitäten, oberflächliche und/oder tiefe Wundinfektionen sind selten, aber mit signifikantem Einfluss auf Morbidität und Mortalität. Insbesondere die steigende Anzahl an älteren Patienten, die mehrere Risikofaktoren aufweisen sind gefährdet sternale Wundkomplikationen zu entwickeln.Patienten und MethodenIn der vorliegenden Studie führen wir zwei Arbeiten zusammen, um den Einfluss des Alters bezüglich postoperativer sternaler Wundkomplikationen zu untersuchen. (1) Aus einem konsekutiven Kollektiv von 339 herzchirurgischen Patienten wurden 86 ältere Patienten (≥75 Jahre) entweder dem konventionellen Sternumverschluss oder der Verschlusstechnik nach Robicsek prospektiv randomisiert. Primäre Endpunkte waren oberflächliche und/oder tiefe sternale Wundinfekte und Sternuminstablilität; sekundäre Endpunkte beinhalteten eine Zusammenfassung klinischer Parameter. (2) Zusätzlich untersuchten wir in einer retrospektiven Arbeit bei 54/5273 Patienten mit Mediastinitis den Einfluss des Alters auf deren weiteren Verlauf.Ergebnisse:(1) Einen statistisch signifikanten Vorteil der Robicsek Verschlusstechnik auf primäre Endpunkte wurde nicht festgestellt, allerdings konnten signifikante Vorteile auf sekundäre Endpunkte gezeigt werden: Nachbeatmung (p=0,03), thorakales Schmerzempfinden >3 Tage (p=0,04) und Krankenhausaufenthaltsdauer (p=0,05). (2) 54/5273 (1,02%) Patienten entwickelten eine Mediastinitis. 12/54 (22%) Patienten verstarben innerhalb 6 Monaten nach der initialer Operation. Risikofaktoren für Mortalität waren Insulin-abhängiger Diabetes mellitus (p=0,05), Niereninsuffizienz (p=0,01), verzögerter Sternumverschluss (p=0,05), Intensivaufenthalt >10 Tage (p=0,01) und Methicillin-resistenter Staphylococcus aureus (p=0,03) oder Pilzinfektion (p=0,02).SchlussfolgerungIn der älteren Bevölkerung bietet der Sternumverschluss nach Robicsek keinen Vorteil bezüglich postoperativer sternalerWundkomplikationen, allerdings sind eindeutige Vorteile bezüglich der Nachbeatmungsdauer, dem thorakalen Schmerzempfinden und der Krankenhausaufenthaltsdauer festzustellen.AbstractBackgroundPostoperative sternal wound complications including superficial and/or deep sternal wound infection and sternal dehiscence are not frequent, but when present impacts significantly morbidity and mortality. Especially the growing population of advanced age patients with several risk factors are prone to suffer sternal wound complications.Patients and methodsIn our present report, we conducted two studies to analyse the influence of advanced age on postoperative sternal wound complications. (1) We present a subset of 86 advanced aged patients (≥75 years) out of a consecutive cohort of 339 cardiac surgery patients prospectively randomised to receive either conventional sternal closure or with the method described by Robicsek. Primary end-points were superficial and/or deep sternal wound infections and sternal dehiscence; secondary end-points included a composite of clinical parameters. (2) In addition, we assess retrospective data of 54/5273 patients with mediastinitis concerning the influence of advanced age on the outcome after therapy.Results(1) There was no statistical impact of the bilateral and longitudinal parasternal wiring on primary end-points. Furthermore, there was significant influence on secondary end-points: ventilation support (p=0.03), chest pain >3 days (p=0.04), and hospital-stay (p=0.05). (2) 54/5273 (1.02%) patients developed postoperative mediastinitis. 12/54 (22%) patients died within 6 months of the initial operation. Predictors of mortality were insulin-dependent diabetes mellitus (p=0.05), renal insufficiency (p=0.01), delayed sternal closure (p=0.05), ICU stay >10 days (p=0.01), and methicillin-resistant Staphylococcus aureus (p=0.03) or fungal-infection (p=0.02).ConclusionIn the elderly population no statistical benefit is found in postoperative sternal wound complication, if the bilateral and longitudinal parasternal closure techniques are performed, but there are obvious positive influences on clinical parameters, like ventilation support, chest pain, and hospital-stay.

Ist Lebensqualität auf der Chirurgischen Intensivstation evaluierbar? Eine klinische Kooperationsstudie Pflege — Arzt

In der vorliegenden Studie wird in Kooperation von Pflegepersonal und Arzt zunachst die Frage nach Erhebungsinstrumenten fur die Evaluierung von Lebensqualitat, dann aber auch betriebs-wirtschaftliche Konsequenzen und Umsetzung der aus der Studie resultierenden Bedurfnisse des Patienten in die tagliche Pflegepraxis diskutiert. Es werden qualitatsrelevante Daten aus objektiver Perspektive, wie Vitalfunktionen, Schwere der Erkrankung aber auch Personalsituation, Behandlungsaufwand und besondere Interventionen mit in einem Interview erfragten Subjektivdaten der Patienten in Beziehung gesetzt. Einzelergebnisse bezuglich des Schmerz- und Schlafempfindens bez. kritisierter Handlungsweisen werden vom Behandlungsteam weitaus negativer eingeschatzt geben aber direkt stationsintern Anlas zu Strategieanderungen in der Behandlung und im allgemeinen Stationsablauf.