Michael C. Truss
Hannover Medical School
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European Urology | 2012
Dionysios Mitropoulos; Walter Artibani; Markus Graefen; Mesut Remzi; Morgan Rouprêt; Michael C. Truss
CONTEXT The incidence of postoperative complications is still the most frequently used surrogate marker of quality in surgery, but no standard guidelines or criteria exist for reporting surgical complications in the area of urology. OBJECTIVE To review the available reporting systems used for urologic surgical complications, to establish a possible change in attitude towards reporting of complications using standardised systems, to assess systematically the Clavien-Dindo system when used for the reporting of complications related to urologic surgical procedures, to identify shortcomings in reporting complications, and to propose recommendations for the development and implementation of future reporting systems that are focused on patient-centred outcomes. EVIDENCE ACQUISITION Standardised systems for reporting and classification of surgical complications were identified through a systematic review of the literature. To establish a possible change in attitude towards reporting of complications related to urologic procedures, we performed a systematic literature search of all papers reporting complications after urologic surgery published in European Urology, Journal of Urology, Urology, BJU International, and World Journal of Urology in 1999-2000 and 2009-2010. Data identification for the systematic assessment of the Clavien-Dindo system currently used for the reporting of complications related to urologic surgical interventions involved a Medline/Embase search and the search engines of individual urologic journals and publishers using Clavien, urology, and complications as keywords. All selected papers were full-text retrieved and assessed; analysis was done based on structured forms. EVIDENCE SYNTHESIS The systematic review of the literature for standardised systems used for reporting and classification of surgical complications revealed five such systems. As far as the attitude of urologists towards reporting of complications, a shift could be seen in the number of studies using most of the Martin criteria, as well as in the number of studies using either standardised criteria or the Clavien-Dindo system. The latter system was not properly used in 72 papers (35.3%). CONCLUSIONS Uniformed reporting of complications after urologic procedures will aid all those involved in patient care and scientific publishing (authors, reviewers, and editors). It will also contribute to the improvement of the scientific quality of papers published in the field of urologic surgery. When reporting the outcomes of urologic procedures, the committee proposes a series of quality criteria.
World Journal of Urology | 2001
Michael C. Truss; Christian G. Stief; Stefan Ückert; Armin J. Becker; J. Wefer; Dirk Schultheiss; Udo Jonas
Abstract Anticholinergic drugs are currently the therapy of choice to treat urgency and urge incontinence. However, muscarinergic receptor blockers with adequate selectivity for detrusor smooth muscle are not available. Also, in contrast to the normal detrusor, the unstable detrusor neurotransmission seems to be at least partially regulated by non-cholinergic (NANC) pathways. These factors may explain the common side effects and the limited clinical efficacy of these compounds. Specific modulation of intracellular second messenger pathways offers the possibility of organ selective manipulation of tissue function, specifically contraction and relaxation of smooth musculature. Because of their central role in the intracellular regulation of smooth muscle tone phosphodiesterases (PDEs) are an attractive pharmacological targets. The PDE 5 specific inhibitor sildenafil (Viagra) has revolutionized the treatment of patients with erectile dysfunction. Numerous other PDE inhibitors are currently under investigation for the treatment of various disorders. We investigated the role of PDEs in human detrusor smooth muscle. Our data demonstrate the presence of five PDE isoenzymes in human detrusor and suggest, for the first time, that the cAMP pathway and the calcium/calmodulin-stimulated PDE (PDE 1) are of functional importance in the intracellular regulation in this tissue in vitro. In addition, initial clinical data with the PDE 1 inhibitor vinpocetine in patients not responding to standard anticholinergic therapy indicate a possible role for vinpocetine in the treatment of urgency, urge incontinence and, possibly, low compliance bladder and interstitial cystitis. The results of a larger randomized, double-blind, placebo-controlled, multicenter trial with vinpocetine show a tendency in favor of vinpocetine over placebo; however, statistically significant results were documented for one parameter only. This might be due to the rather low dosage chosen and the small sample size. Further studies are necessary and currently underway to delineate the optimal dosage, indications and patient population. Modulation of intracellular key enzymes effecting second messenger metabolism, i.e. isoenzyme-selective PDE inhibition is a novel approach which possibly avoids the limitations of anticholinergic therapy in patients with lower urinary tract dysfunction.
The Journal of Urology | 2006
Martin L. Metzelder; Felix Schier; Claus Petersen; Michael C. Truss; Benno M. Ure
PURPOSE We assessed the feasibility of laparoscopic transabdominal dismembered pyeloplasty in 46 infants and children with regard to patient age. MATERIALS AND METHODS A total of 46 consecutive infants and children (31 male and 15 female) underwent laparoscopic transabdominal dismembered pyeloplasty using a 3 to 4-trocar technique. All patients had confirmed unilateral deterioration of renal function on isotope renography. The 46 patients were divided into 3 age groups--1 to 12 months (group 1, 14 patients), 1 to 7 years (group 2, 15 patients) and 7 to 18 years (group 3, 17 patients). Followup included clinical and ultrasound assessment, and isotope renography at 3 months. RESULTS Laparoscopic pyeloplasty was feasible in 44 of 46 patients (96%). Mean operative time was 175 minutes (range 120 to 270). The operation was converted due to impracticality of stenting the PUJ in 1 patient, and due to bleeding in 1. Mean operative time in 44 successful laparoscopic procedures was not significantly different among the 3 age groups (171 minutes in group 1, 169 minutes in group 2 and 173 minutes in group 3). Two patients required operative intervention for PUJ leakage, and 1 underwent percutaneous nephrostomy with a further uneventful course. Mean followup was 29 months (range 3 to 86). A total of 44 patients (96%) were asymptomatic and had improved PUJ drainage on isotope renography. Two patients underwent redo pyeloplasty due to recurrent hydronephrosis at 1 month and 2 years. CONCLUSIONS Laparoscopic transabdominal dismembered pyeloplasty is effective and safe in infants and children. The feasibility is also excellent in patients younger than 1 year. The transabdominal approach revealed good exposition without a disadvantage for the patient.
Urological Research | 1996
Michael C. Truss; Stefan Ückert; Christian G. Stief; Wolf-Georg Forssmann; Udo Jonas
Phosphodiesterases (PDEs) are key enzymes involved in the regulation of intracellular cyclic nucleotide metabolism. The aim of the present study was to identify and to characterize the PDE isoenzymes present in the human detrusor smooth muscle. Human detrusor PDE isoenzymes were separated by Q-Sepharose anion exchange and calmodulin-agarose affinity chromatography and characterized upon their kinetic characteristics and their sensitivity to allosteric modulators and inhibitors. All five presently known PDE isoenzyme families were identified: one high-affinity, low-Km calcium/calmodulin-stimulated PDE I with a slight preference for cGMP over cAMP, one cGMP-stimulated PDE II, one cGMP-inhibited PDE III, one cAMP-specific PDE IV and one cGMP-specific PDE IV. All five known PDE isoenzyme families exist in human detrusor smooth musculature. The kinetic characteristics, together with functional in vitro studies, suggest that the PDE I may be of importance in the intracellular regulation of the human detrusor smooth muscle tone.
Urology | 2001
Armin J. Becker; Stefan Ückert; Christian G. Stief; Michael C. Truss; Stefan Machtens; Friedemann Scheller; Wolfram H. Knapp; Uwe Hartmann; Udo Jonas
OBJECTIVES To examine the functional effects of bradykinin (BK) and angiotensin II (AN II) on isolated human cavernous tissue and to detect any changes in the AN II levels in cavernous and peripheral blood samples taken from healthy volunteers at different functional conditions of the penile erectile tissue. Metabolites of the renin-angiotensin system and endothelium-derived vasoactive substances are known to be involved in the regulation of arterial vascular tone. The human corpus cavernosum (HCC), consisting of endothelial and smooth muscle cells, can be regarded as a compartment comparable to the vascular system. METHODS The relaxing and contracting properties of BK and AN II on isolated HCC were investigated using the organ bath technique. Tissue levels of adenosine-3,5-cyclic monophosphate (cAMP) and guanosine-3,5-cyclic monophosphate (cGMP) were determined using specific radioimmunoassays, after exposing isolated HCC strips in a dose-dependent manner to BK, forskolin, and sodium nitroprusside. Blood samples were drawn simultaneously from the corpus cavernosum and cubital vein of 34 healthy volunteers at stages of penile flaccidity, tumescence, rigidity, and detumescence. Penile erection was induced by audiovisual and tactile stimulation. AN II levels were determined using a radioimmunoassay. RESULTS In vitro, BK, forskolin, and sodium nitroprusside elicited dose-dependent relaxation of norepinephrine-induced tension of isolated HCC, and AN II evoked dose-dependent contraction of the HCC strips. The relaxing potency of BK was paralleled by its ability to elevate the intracellular levels of cAMP and cGMP. In vivo, the AN II levels in the cavernous plasma increased from 21.8 +/- 4.6 pg/mL in the flaccidity phase to 27.9 +/- 10 pg/mL in the detumescence phase. In the peripheral plasma, the AN II levels were 17.2 +/- 6.2 to 19.5 +/- 6.5 pg/mL in the respective penile stages. Thus, the mean AN II levels in the cavernous blood were about 30% higher than in the blood samples taken from the cubital vein. In the cavernous blood, the increase in the AN II plasma levels in the detumescence phase (27.9 +/- 10 pg/mL) was statistically significant. CONCLUSIONS Our results suggest that penile cavernous smooth muscle tone is partially balanced by kinin-induced relaxation and AN II-induced contraction. Since the tissue and plasma levels of both peptides are regulated by the activity of the angiotensin-converting enzyme, there might be a rationale for the use of angiotensin-converting enzyme inhibitors in the treatment of erectile dysfunction associated with arterial hypertension.
World Journal of Urology | 2003
Jens-Uwe Stolzenburg; Michael C. Truss; Minh Do; Robert Rabenalt; Heidemarie Pfeiffer; Michael Dunzinger; Bernd Aedtner; Christian G. Stief; Udo Jonas; Wolfgang Dorschner
During the last decade, laparoscopy has become a standard technique in the armoury of the urologist due to constant technological advances and refinements. Laparoscopic radical prostatectomy (LRPE), although technically demanding and associated with a considerable learning curve, has become the surgical procedure of choice in selected and specialized urological centers around the globe for patients with clinically localized prostate cancer. However, a major drawback of LRPE is the transperitoneal route of access to the extraperitoneal prostate. The principal disadvantages of LRPE are potential intraperitoneal complications, such as bowel injury, ileus, intraperitoneal bleeding, intraperitoneal urinary leakage, intraperitoneal adhesion formation and concomitant small bowel obstruction. Endoscopic extraperitoneal radical prostatectomy (EERPE) is a further advancement of minimal invasive surgery as it overcomes the limitations of LRPE by the strictly extraperitoneal route of access combining the advantages of minimal invasive surgery with those of an extraperitoneal procedure. Based on our growing experience with this procedure, we have introduced several technical modifications, improvements and refinements including a nerve-sparing, potency-preserving approach (nEERPE) in an effort to further improve this minimally invasive procedure.
The Journal of Urology | 1998
Armin J. Becker; Christian G. Stief; Stephan Machtens; Dirk Schultheiss; Uwe Hartmann; Michael C. Truss; Udo Jonas
PURPOSE For most patients with erectile dysfunction oral agents are a preferred treatment option. Oral or buccal phentolamine has been shown to produce full erections in impotent subsets of study populations. We evaluate the efficacy of oral phentolamine. MATERIALS AND METHODS After a comprehensive evaluation 44 patients with recent onset (less than 3 years) of erectile dysfunction and a high likelihood of organogenic etiology underwent a prospective, double-blind and placebo controlled trial with oral phentolamine after placebo. RESULTS After placebo 4 of the 44 patients who reported full erections were excluded from study. Of the 40 patients in the double-blind phase full erections were achieved by 2 of 10 with placebo, and 3 of 10 with 20 mg., 5 of 10 with 40 mg. and 4 of 10 with 60 mg. phentolamine. There were no serious complications observed during the study, and only a single minor side effect occurred in 1 patient after 60 mg. phentolamine. CONCLUSIONS Our results indicate that oral phentolamine may be of benefit for the treatment of erectile dysfunction. Further studies are required to corroborate our findings.
BJUI | 2005
Jens-Uwe Stolzenburg; Hartwig Schwaibold; Shiv Mohan Bhanot; Robert Rabenalt; Minh Do; Michael C. Truss; Kossen Ho; Christopher J. Anderson
To develop a modular training scheme which enabled the use of individual steps of laparoscopic radical prostatectomy (RP) for teaching and training surgeons with varied experience, including residents with no experience in open RP, as in extending laparoscopic surgery to more complex operations like RP, the proper training of urologists is crucial.
World Journal of Urology | 2000
Michael C. Truss; Christian G. Stief; Stefan Ückert; Armin J. Becker; Dirk Schultheiss; Stefan Machtens; Udo Jonas
Abstract Current pharmacological treatment modalities for urge incontinence and low compliance bladder are limited by a low clinical efficacy and the significant side effects of the standard drugs available. Previous in vitro studies indicated a possible functional relevance of the intracellular phosphodiesterase (PDE)-1 isoenzyme in the regulation of human detrusor smooth muscle contractility. We therefore investigated the effect of the PDE-1 inhibitor vinpocetine in nonresponders to standard pharmacological therapy. In 11/19 patients (57.9%) clinical symptoms and/or urodynamic parameters were improved. Although these initial data are preliminary, they represent the first evidence that isoenzyme-selective PDE inhibition may be a novel approach to the treatment of lower urinary tract disorders.
BJUI | 2003
J.-U. Stolzenburg; Michael C. Truss
During the last decade laparoscopy has become a standard technique available to the urologist, through constant technological advances and refinements. The progress of laparoscopic/endoscopic techniques allows the indications for this surgery to include complex oncological procedures like radical prostatectomy. Since the first description of laparoscopic radical prostatectomy (LRP) in the early 1990s the technique has undergone significant technical modifications. Transperitoneal LRP is now a standard procedure and can be used successfully and reproducibly, giving results comparable with those from the open retropubic procedure. Despite many advantages, transperitoneal laparoscopy is associated with potential intraperitoneal complications. Because of the limitations inherent in the transperitoneal route, a totally extraperitoneal endoscopic radical prostatectomy (EERPE) has been developed. The totally extraperitoneal endoscopic access provides a safe and minimally invasive approach to various urological procedures, including prostatectomy. This technical improvement completely obviates intra‐abdominal complications. EERPE combines the advantages of minimally invasive laparoscopy and the open retropubic approach. We review the surgical techniques of LRP and EERPE, and highlight the indications, contraindications and outcomes.