Topographic variability of the esophageal left atrial relation influencing ablation lines in patients with atrial fibrillation.

UNLABELLED Topography of the esophagus in atrial fibrillation ablation. INTRODUCTION The close anatomic relationship of the posterior wall of the left atrium (LA) and the thermosensitive esophagus creates a potential hazard in catheter ablation procedures. METHODS AND RESULTS In 30 patients (pts) with atrial fibrillation (AF) undergoing catheter ablation, we prospectively studied the course and contact of the esophagus in relation to LA and the topographic proximity to ablation lines encircling the right-sided and left-sided pulmonary veins (PV) as well as to the posterior line connecting the encircling lines using the electromagnetic mapping system for reconstruction of LA and for tagging of the esophagus. This new technique of anatomic tagging of the esophagus was validated against the CT scan as a standard imaging procedure. The esophageal course was highly variable, extending from courses in direct vicinity to the left- or right-sided PV as well as in the midportion of the posterior LA. In order to avoid energy application in direct proximity to the esophagus, adjustments of the left and right PV encircling lines were necessary in 14/30 pts (47%) and 3/30 (10%). In 30 pts (100%), the mid- to inferior areas of the posterior LA revealed contact with the esophagus. Therefore, posterior and inferior linear ablation lines were abandoned and shifted to superior in 29 pts (97%). CONCLUSIONS Anatomic tagging of esophagus revealed a highly variable proximity to different areas of the posterior LA suggesting individual adjustment of encircling and linear ablation lines in AF ablation procedures to avoid the life threatening complication of esophagus perforation.

β-Glucan Antigenemia Anticipates Diagnosis of Blood Culture–Negative Intraabdominal Candidiasis

Rationale: Life-threatening intraabdominal candidiasis (IAC) occurs in 30 to 40% of high-risk surgical intensive care unit (ICU) patients. Although early IAC diagnosis is crucial, blood cultures are negative, and the role of Candida score/colonization indexes is not established. Objectives: The aim of this prospective Fungal Infection Network of Switzerland (FUNGINOS) cohort study was to assess accuracy of 1,3-β-d-glucan (BG) antigenemia for diagnosis of IAC. Methods: Four hundred thirty-four consecutive adults with abdominal surgery or acute pancreatitis and ICU stay 72 hours or longer were screened: 89 (20.5%) at high risk for IAC were studied (68 recurrent gastrointestinal tract perforation, 21 acute necrotizing pancreatitis). Diagnostic accuracy of serum BG (Fungitell), Candida score, and colonization indexes was compared. Measurements and Main Results: Fifty-eight of 89 (65%) patients were colonized by Candida; 29 of 89 (33%) presented IAC (27 of 29 with negative blood cultures). Nine hundred twenty-one sera were analyzed (9/patient): median BG was 253 pg/ml (46–9,557) in IAC versus 99 pg/ml (8–440) in colonization (P < 0.01). Sensitivity and specificity of two consecutive BG measurements greater than or equal to 80 pg/ml were 65 and 78%, respectively. In recurrent gastrointestinal tract perforation it was 75 and 77% versus 90 and 38% (Candida score ≥ 3), 79 and 34% (colonization index ≥ 0.5), and 54 and 63% (corrected colonization index ≥ 0.4), respectively. BG positivity anticipated IAC diagnosis (5 d) and antifungal therapy (6 d). Severe sepsis/septic shock and death occurred in 10 of 11 (91%) and 4 of 11 (36%) patients with BG 400 pg/ml or more versus 5 of 18 (28%, P = 0.002) and 1 of 18 (6%, P = 0.05) with BG measurement less than 400 pg/ml. β-Glucan decreased in IAC responding to therapy and increased in nonresponse. Conclusions: BG antigenemia is superior to Candida score and colonization indexes and anticipates diagnosis of blood culture–negative IAC. This proof-of-concept observation in strictly selected high-risk surgical ICU patients deserves investigation of BG-driven preemptive therapy.

P2X7 receptors mediate resistance to toxin-induced cell lysis

In the majority of cells, the integrity of the plasmalemma is recurrently compromised by mechanical or chemical stress. Serum complement or bacterial pore-forming toxins can perforate the plasma membrane provoking uncontrolled Ca(2+) influx, loss of cytoplasmic constituents and cell lysis. Plasmalemmal blebbing has previously been shown to protect cells against bacterial pore-forming toxins. The activation of the P2X7 receptor (P2X7R), an ATP-gated trimeric membrane cation channel, triggers Ca(2+) influx and induces blebbing. We have investigated the role of the P2X7R as a regulator of plasmalemmal protection after toxin-induced membrane perforation caused by bacterial streptolysin O (SLO). Our results show that the expression and activation of the P2X7R furnishes cells with an increased chance of surviving attacks by SLO. This protective effect can be demonstrated not only in human embryonic kidney 293 (HEK) cells transfected with the P2X7R, but also in human mast cells (HMC-1), which express the receptor endogenously. In addition, this effect is abolished by treatment with blebbistatin or A-438079, a selective P2X7R antagonist. Thus blebbing, which is elicited by the ATP-mediated, paracrine activation of the P2X7R, is part of a cellular non-immune defense mechanism. It pre-empts plasmalemmal damage and promotes cellular survival. This mechanism is of considerable importance for cells of the immune system which carry the P2X7R and which are specifically exposed to toxin attacks.

Ceramide in Plasma Membrane Repair

The perforation of the plasmalemma by pore-forming toxins causes an influx of Ca2+ and an efflux of cytoplasmic proteins. In order to ensure cellular survival, lesions have to be identified, plugged and removed from the membrane. The Ca2+-driven fusion of lysosomes with the plasma membrane leads to hydrolysis of sphingomyelin by acid sphingomyelinase and a formation of ceramide platforms in the outer leaflet of the lipid bilayer. We propose that the negative curvature, promoted by tighter packing of lipids in the outer layer, leads to an inward vesiculation of the damaged area for its endocytotic uptake and internal degradation. In contrast, the activation of neutral sphingomyelinase triggers the production of ceramide within the inner leaflet of the lipid bilayer, thereby promoting an outward curvature, which enables the cell to shed the membrane-containing toxin pore into the extracellular space. In this process, ceramide is supported by members of the annexin protein family which act as Ca2+ sensors and as membrane fusion agents.

Is thermochemotherapy with the Synergo system a viable treatment option in patients with recurrent non-muscle-invasive bladder cancer?

OBJECTIVES To prospectively evaluate the outcome of combined microwave-induced bladder wall hyperthermia and intravesical mitomycin C instillation (thermochemotherapy) in patients with recurrent non-muscle-invasive bladder cancer. METHODS Between 2003 and 2009, 21 patients (median age 70 years, range 35-95 years) with recurrent non-muscle-invasive bladder cancer (pTaG1-2 n = 9; pTaG3 n = 3; pT1 n = 9; concurrent pTis n = 8) were prospectively enrolled. Of 21 patients, 15 (71%) had received previous intravesical instillations with bacillus Calmette-Guérin, mitomycin C and/or farmorubicin. Thermochemotherapy using the Synergo system was carried out in 11 of 21 patients (52%) with curative intent, and in 10 of 21 patients (48%) as prophylaxis against recurrence. RESULTS The median number of thermochemotherapy cycles per patient was six (range 1-12). Adverse effects were frequent and severe: urinary urgency/frequency in 11 of 21 patients (52%), pain in eight of 21 patients (38%) and gross hematuria in five of 21 patients (24%). In eight of 21 patients (38%), thermochemotherapy had to be abandoned because of the severity of the adverse effects (pain in 3/8, severe bladder spasms in 2/8, allergic reaction in 2/8, urethral perforation in 1/8). Overall, six of 21 patients (29%) remained free of tumor after a median follow up of 50 months (range 1-120), six of 21 patients (29%) had to undergo cystectomy because of multifocal recurrences or cancer progression and seven of 21 patients (33%) died (2/7 of metastatic disease, 5/7 of non-cancer related causes). CONCLUSIONS Given the high rate of severe side-effects leading to treatment discontinuation, as well as the limited tumor response, thermochemotherapy should be offered only in highly selected cases of recurrent non-muscle-invasive bladder cancer.

Fractures in Children and Adolescents

Fractures of the growing bone require fixation techniques, which preclude any injury to the growth plate regions. This requirement is met by Elastic Stable Intramedullary Nails (ESIN) which are positioned between both metaphyseal regions. Pronounced malposition and/or shortening, open fractures and fractures with impending skin perforation are indications for clavicle nailing in adolescents. Retrograde nailing with two elastic nails, inserted from lateral, is the method of choice for stabilization of humerus fractures. In radial neck fractures with severe tilting of the radial head, a retrograde nail may reduce and fix the head. In Monteggia lesions, the ulna fracture is reduced and fixed with an antegrade nail. Forearm fractures with unacceptable axial deviation are reduced and fixed with one antegrade nail in the ulna and a retrograde nail in the radius. Ascending elastic nailing is done for femur shaft and proximal femur fractures. The medial and lateral entry sites are located above the distal physis. End caps are used to prevent shortening in spiral and multiple segment fractures. Fractures of the distal third of the femur are nailed in a descending technique. The entry sites of two nails are located on the lateral cortex below the greater trochanter. Combined tibia and fibula fractures, open fractures and unstable fracture types such as spiral and multifragmental tibia fractures are good indications for ESIN. Descending nailing is the method of choice. The nail entry points are medially and laterally distal to the apophysis of the proximal tibia. Thorough knowledge of each fracture type, fracture location and age specific healing pattern is necessary for safe and effective treatment of pediatric fractures

Primum et super omnium: nihil nocere Operationsindikation im Wandel bei Divertikulitis

Diverticulitis is a common disease in western countries and its incidence is increasing especially among young patients. Colonic diverticulosis, incidentally diagnosed by endoscopy or CT-scanning, has no immediate clinical consequences. Progression to diverticulitis develops in only 4 % of cases. In the last decades management of diverticular disease evolved and expectative treatment and less invasive techniques have gained importance. Elective resection has traditionally been advised after a second episode of diverticulitis or after a first episode if the patient was less than 50 years of age or complicated disease occurred. Recent changes in understanding the natural history of diverticular disease have substantially modified treatment paradigms. Elective resection in case of recurrent diverticular disease should be performed on a individual basis and in cases with complications like intestinal obstruction or fistulas. Primary anastomosis is an option even in emergency surgery due to colonic perforation, while diverting operations are indicated for selected patient groups with a high risk profile. Several prospective studies showed good results for laparoscopic drainage and lavage in the setting of perforated diverticulitis with generalized peritonitis, though this concept needs to be controlled with randomized clinical trials before application into the daily practice. This article should provide a short overview of trends in the surgical treatment of diverticulitis, help to understand the natural history of the disease and thereby explain the currently lower frequency of surgical interventions for diverticulitis.

Additional surgical procedure is a risk factor for surgical site infections after laparoscopic cholecystectomy

PURPOSE: Surgical site infections (SSI) are associated with increased costs and length of hospital stay, readmission rates, and mortality. The aim of this study was to identify risk factors for SSI in patients undergoing laparoscopic cholecystectomy. METHODS: Analysis of 35,432 laparoscopic cholecystectomies of a prospective multicenter database was performed. Risk factors for SSI were identified among demographic data, preoperative patients' history, and operative data using multivariate analysis. RESULTS: SSIs after laparoscopic cholecystectomy were seen in 0.8 % (n = 291) of the patients. Multivariate analysis identified the following parameters as risk factors for SSI: additional surgical procedure (odds ratio [OR] 4.0, 95 % confidence interval [CI] 2.2-7.5), age over 55 years (OR 2.4 [1.8-3.2]), conversion to open procedure (OR 2.6 [1.9-3.6]), postoperative hematoma (OR 1.9 [1.2-3.1]), duration of operation >60 min (OR 2.5 [1.7-3.6], cystic stump insufficiency (OR 12.5 [4.2-37.2]), gallbladder perforation (OR 6.2 [2.4-16.1]), gallbladder empyema (OR 1.7 [1.1-2.7]), and surgical revision (OR 15.7 [10.4-23.7]. SSIs were associated with a significantly prolonged hospital stay (p < 0.001), higher postoperative mortality (p < 0.001), and increased rate of surgical revision (p < 0.001). CONCLUSIONS: Additional surgical procedure was identified as a strong risk factor for SSI after laparoscopic cholecystectomy. Furthermore, operation time >60 min, age >55 years, conversion to open procedure, cystic stump insufficiency, postoperative hematoma, gallbladder perforation, gallbladder empyema, or surgical revision were identified as specific risk factors for SSI after laparoscopic cholecystectomy.

Efficient and Safe Small-Bowel Adhesiolysis

Small-intestine adhesiolysis can be very time consuming and may be associated with bowel wall damage. The risk for injuries to the small or large bowel resulting in increased morbidity and costs is considerable. Both efficient and gentle dissection of adhesions is important in order to avoid intraoperative perforation or, worse, postoperative intestinal leaks. We present a technique using drops of body-warm isotonic saline solution to create an edematous swelling of the adhesions. This procedure not only protects the bowel from cooling and drying, but also simplifies the dissection and, thus, lowers the risk of intestinal lesions.

Survival after trepanation—Early cranial surgery from Late Iron Age Switzerland

Trepanation is defined as the intentional perforation of the cranial vault with removal of a piece of skull bone. In Europe, trepanation is known to have been practiced at least since the Neolithic, and it can still be found today in East African native tribes. Two skulls with lesions from the Late Iron Age site Münsingen-Rain (420–240 BC) were investigated. The aim of this study was to analyse the lesions and to determine whether they were caused by surgical interventions. Both individuals were analysed by current morphologic-anthropological methods and radiological examinations were performed with a multislice CT-scanner. Additionally, this work surveys trepanations reported in Switzerland and calculates survival rates. In Switzerland, 34 individuals with trepanations have been published. As a tendency, the survival rate appears to be relatively high from the Neolithic to Late Antiquity but then decreases until Pre-Modern times. The 78% survival rate in Late Iron Age Switzerland indicates that the surgery was often performed successfully. Skull injuries sustained in conflicts could have been a reason for trepanation during the Iron Age.

Radiation dose in pneumatic reduction of ileo-colic intussusceptions--results from a single-institution study

BACKGROUND Air enema under fluoroscopy is a well-accepted procedure for the treatment of childhood intussusception. However, the reported radiation doses of pneumatic reduction with conventional fluoroscopy units have been high in decades past. OBJECTIVE To compare current radiation doses at our institution to past doses reported by others for fluoroscopic-guided pneumatic reduction of ileo-colic intussusception in children. MATERIALS AND METHODS Since 2007 radiologists and residents in our department who perform reduction of intussusceptions have received a radiation risk training. We retrospectively analyzed the data of 45 children (5 months-8 years) who underwent a total of 48 pneumatic reductions of ileo-colic intussusception between 2008 and 2012. We analyzed data for screening time and dose area product (DAP) and compared these data to those reported up to and including the year 2000. RESULTS Our mean screening time measured by the DAP-meter was 53.8 s (range 1-320 s, median 33.0 s). The mean DAP was 11.4 cGy ∙ cm(2) (range 1-145 cGy ∙ cm(2), median 5.45 cGy ∙ cm(2)). There was one bowel perforation, in a 1-year-old boy requiring surgical revision. Only three studies in the literature presented radiation exposure results on children who received pneumatic or hydrostatic reduction of intussusception under fluoroscopy. Screening times and dose area products in those studies, which were published in the 1990 s and in the year 2000, were substantially higher than those in our sample. CONCLUSION Low-frequency pulsed fluoroscopy and other dose-saving keys as well as the radiation risk training might have helped to improve the quality of the procedure in terms of radiation exposure.

Defying death: Cellular survival strategies following plasmalemmal injury by bacterial toxins

The perforation of the plasmalemma by pore-forming toxins causes an influx of Ca(2+) and an efflux of cytoplasmic constituents. In order to ensure survival, the cell needs to identify, plug and remove lesions from its membrane. Quarantined by membrane folds and isolated by membrane fusion, the pores are removed from the plasmalemma and expelled into the extracellular space. Outward vesiculation and microparticle shedding seem to be the strategies of choice to eliminate toxin-perforated membrane regions from the plasmalemma of host cells. Depending on the cell type and the nature of injury, the membrane lesion can also be taken up by endocytosis and degraded internally. Host cells make excellent use of an initial, moderate rise in intracellular [Ca(2+)], which triggers containment of the toxin-inflicted damage and resealing of the damaged plasmalemma. Additional Ca(2+)-dependent defensive cellular actions range from the release of effector molecules in order to warn neighbouring cells, to the activation of caspases for the initiation of apoptosis in order to eliminate heavily damaged, dysregulated cells. Injury to the plasmalemma by bacterial toxins can be prevented by the early sequestration of bacterial toxins. Artificial liposomes can act as a decoy system preferentially binding and neutralizing bacterial toxins.