Longer small bowel segments are resected in emergency surgery for ileocaecal Crohn's disease with a higher ileostomy and complication rate.

BACKGROUND: Repeated intestinal resections may have disabling consequences in patients with Crohn's disease even in the absence of short bowel syndrome. Our aim was to evaluate the length of resected small bowel in patients undergoing elective and emergency surgery for ileocolic Crohn's disease. METHODS: A prospective observational study was conducted on patients undergoing surgery for ileocolonic Crohn's disease in a single colorectal centre from May 2010 to April 2018. The following patients were included: (1) patients with first presentation of ileocaecal Crohn's disease undergoing elective surgery; (2) patients with ileocaecal Crohn's disease undergoing emergency surgery; (3) patients with recurrent Crohn's disease of the distal ileum undergoing elective surgery. The primary outcomes were length of resected small bowel and the ileostomy rate. Operating time, complications and readmissions within 30 days were the secondary outcomes. RESULTS: One hundred and sixty-eight patients were included: 87 patients in the elective primary surgery group, 50 patients in the emergency surgery group and 31 in the elective redo surgery group. Eleven patients (22%) in the emergency surgery group had an ileostomy compared to 10 (11.5%) in the elective surgery group (p < 0.0001). In the emergency surgery group the median length of the resected small bowel was 10 cm longer than into the group having elective surgery for primary Crohn's disease. CONCLUSIONS: Patients undergoing emergency surgery for Crohn's disease have a higher rate of stoma formation and 30-day complications. Laparoscopic surgery in the emergency setting has a higher conversion rate and involves resection of longer segments of small bowel.

2D versus 3D laparoscopic total mesorectal excision: a developmental multicentre randomised controlled trial.

AIMS: The role of laparoscopy in rectal cancer has been questioned. 3D laparoscopic systems are suggested to aid optimal surgical performance but have not been evaluated in advanced procedures. We hypothesised that stereoscopic imaging could improve the performance of laparoscopic total mesorectal excision (TME). METHODS: A multicentre developmental randomised controlled trial comparing 2D and 3D laparoscopic TME was performed (ISRCTN59485808). Trial surgeons were colorectal consultants that had completed their TME proficiency curve and underwent stereoscopic visual testing. Patients requiring elective laparoscopic TME with curative intent were centrally randomised (1:1) to 2D or 3D using Karl Storz IMAGE1 S D3-Link™ and 10-mm TIPCAM®1S 3D passive polarising laparoscopic systems. Outcomes were enacted adverse events as assessed by the observational clinical human reliability analysis technique, intraoperative data, 30-day patient outcomes, histopathological specimen assessment and surgeon cognitive load. RESULTS: 88 patients were included. There were no differences in patient or tumour demographics, surgeon stereopsis, case difficulty, cognitive load, operative time, blood loss or conversion between the trial arms. 1377 intraoperative adverse events were identified (median 18 per case, IQR 14-21, range 2-49) with no differences seen between the 2D and 3D arms (18 (95% CI 17-21) vs. 17 (95% CI 16-19), p = 0.437). 3D laparoscopy had non-significantly higher mesorectal fascial plane resections (94 vs. 77%, p = 0.059; OR 0.23 (95% CI 0.05-1.16)) but equal lymph node yield and circumferential margin distance and involvement. 30-day morbidity, anastomotic leak, re-operation, length of stay and readmission rates were equal between the 2D and 3D arms. CONCLUSION: Feasibility of performing multicentre 3D laparoscopic multicentre trials of specialist performed complex procedures is shown. 3D imaging did not alter the number of intraoperative adverse events; however, a potential improvement in mesorectal specimen quality was observed and should form the focus of future 3D laparoscopic TME trials.

Laparoscopic Redo Ileocolic Resection for Crohn's Disease in Patients with Previous Multiple Laparotomies.

PURPOSES:: Over 80% of patients with primary ileocolic Crohn's disease have a surgical resection within 10 years of diagnosis, and 40%-50% of them need further surgery within 15 years. Laparoscopic surgery can be challenging due to a thickened mesentery and the potential for fistulas, abscesses, and phlegmons. Aim of this study is to analyze the short-term outcomes of laparoscopic redo ileocolic resections for Crohn's disease in patients with previous multiple laparotomies. METHODS:: All patients undergoing laparoscopic surgery for ileocolic Crohn's disease from March 2006 to February 2017 were prospectively evaluated. Short term outcomes of laparoscopic ileocolic resection were compared between patients with previous multiple major surgeries and recurrent Crohn's disease, and patients undergoing surgery for the first presentation of Crohn's disease and no history of previous surgery. Conversion rate and 30-day morbidity were the primary outcomes. Reoperations, readmissions, operating time and length of stay were the secondary outcomes. RESULTS:: 29 patients with recurrent Crohn's disease and previous multiple laparotomies were included: the number of laparotomies these patients previously underwent was 2 in 19 cases (65.5%), 3 in 9 (31%), and 4 in 1 (3.5%). In total, 90 patients with no history of any previous abdominal surgery, who underwent laparoscopic ileocecal resection for Crohn's disease, represented the control group. No differences were found in morbidity and conversion rate. Operating time was longer in patients with history of previous abdominal surgery. CONCLUSION:: Laparoscopic redo ileocolic resection for Crohn's disease is feasible and safe in patients with previous multiple laparotomies at the expense of longer operating time.

EAES classification of intraoperative adverse events in laparoscopic surgery.

BACKGROUND: Surgical outcomes are traditionally evaluated by post-operative data such as histopathology and morbidity. Although these outcomes are reported using accepted systems, their ability to influence operative performance is limited by their retrospective application. Interest in direct measurement of intraoperative events is growing but no available systems applicable to routine practice exist. We aimed to develop a structured, practical method to report intraoperative adverse events enacted during minimal access surgical procedures. METHODS: A structured mixed methodology approach was adopted. Current intraoperative adverse event reporting practices and desirable system characteristics were sought through a survey of the EAES executive. The observational clinical human reliability analysis method was applied to a series of laparoscopic total mesorectal excision (TME) case videos to identify intraoperative adverse events. In keeping with survey results, observed events were further categorised into non-consequential and consequential, which were further subdivided into four levels based upon the principle of therapy required to correct the event. A second survey phase explored usability, acceptability, face and content validity of the novel classification. RESULTS: 217 h of TME surgery were analysed to develop and continually refine the five-point hierarchical structure. 34 EAES expert surgeons (69%) responded. The lack of an accepted system was the main barrier to routine reporting. Simplicity, reproducibility and clinical utility were identified as essential requirements. The observed distribution of intraoperative adverse events was 60.1% grade I (non-consequential), 37.1% grade II (minor corrective action), 2.4% grade III (major correction or change in post-operative care) and 0.1% grade IV (life threatening). 84% agreed with the proposed classification (Likert scale 4.04) and 92% felt it was applicable to their practice and incorporated all desirable characteristics. CONCLUSION: A clinically applicable intraoperative adverse event classification, which is acceptable to expert surgeons, is reported and complements the objective assessment of minimal access surgical performance.

Designing a high performance, stable spectroscopic biosensor for the binding of large and small molecules.

In the context of FTIR ATR-based sensors, the organic layer covering the ATR element has to be as stable as possible for optimal spectroscopic measurements. Previously, this self-assembled covering was considered stable after several hours under a PBS flux, probably due to a hydrophobic barrier, which prevents water penetration into the grafted network. Stability and reactivity, measured simultaneously using FTIR ATR, identify the limits of the previously used molecular construction. For the first time, surface etching of the previous functionalised Ge devices (Ge-PEG-NHS), a few minutes after BSA injection, was observed. It was concluded that the molecular chain deformation of Ge-PEG-NHS likely occurred when large molecules were bound. BSA loaded onto a Ge-PEG-NHS surface led to network deprotection, with the probable disruption of hydrogen bonds for single barrier-based networks. This, in turn, was presumably influenced by the random deposition of the NHS moiety on the PEG chain. A new functionalised germanium device, using a rapid three-step in situ procedure, provides an efficient robust network composed of two protective barriers, ideal for the binding of various sized molecules. The Ge-APS-PEG-NHS device has shown exceptional sensitivity with regards to BSA and ethanolamine target molecules while offering homogeneous NHS distribution.

Bayesian networks to identify statistical dependencies. A case study of Spanish university students' habits.

OBJECTIVE: The present study sought to discover the relationships among different features characterizing Spanish university students' habits through a Bayesian network (BN). The set of features with the strongest influence in specific features can be determined. METHODS: A BN was built from a dataset composed of 13 relevant features, determining the dependencies and conditional independencies from empirical data in a multivariate context. The structure was learned with the bnlearn package in R language introducing prior knowledge, and the parameters were obtained with Netica software. Three reasoning patterns were considered to make inferences: intercausal, evidential, and causal reasoning. RESULTS: BN determined the different relationships. Through inference several conclusions were achieved, for instance a high probability value of physical activity in low state was obtained when active peers were instantiated to none state, self-rated fitness to fair state, bmi to normal weight, sitting time to moderate, age to 22-25, and gender to woman state. CONCLUSIONS: Bayesian networks may help to characterize Spanish University students' habits.

Application of objective clinical human reliability analysis (OCHRA) in assessment of technical performance in laparoscopic rectal cancer surgery.

BACKGROUND: Laparoscopic rectal resection is technically challenging, with outcomes dependent upon technical performance. No robust objective assessment tool exists for laparoscopic rectal resection surgery. This study aimed to investigate the application of the objective clinical human reliability analysis (OCHRA) technique for assessing technical performance of laparoscopic rectal surgery and explore the validity and reliability of this technique. METHODS: Laparoscopic rectal cancer resection operations were described in the format of a hierarchical task analysis. Potential technical errors were defined. The OCHRA technique was used to identify technical errors enacted in videos of twenty consecutive laparoscopic rectal cancer resection operations from a single site. The procedural task, spatial location, and circumstances of all identified errors were logged. Clinical validity was assessed through correlation with clinical outcomes; reliability was assessed by test-retest. RESULTS: A total of 335 execution errors identified, with a median 15 per operation. More errors were observed during pelvic tasks compared with abdominal tasks (p < 0.001). Within the pelvis, more errors were observed during dissection on the right side than the left (p = 0.03). Test-retest confirmed reliability (r = 0.97, p < 0.001). A significant correlation was observed between error frequency and mesorectal specimen quality (r s = 0.52, p = 0.02) and with blood loss (r s = 0.609, p = 0.004). CONCLUSIONS: OCHRA offers a valid and reliable method for evaluating technical performance of laparoscopic rectal surgery.

Islet product characteristics and factors related to successful human islet transplantation from the Collaborative Islet Transplant Registry (CITR) 1999-2010.

The Collaborative Islet Transplant Registry (CITR) collects data on clinical islet isolations and transplants. This retrospective report analyzed 1017 islet isolation procedures performed for 537 recipients of allogeneic clinical islet transplantation in 1999-2010. This study describes changes in donor and islet isolation variables by era and factors associated with quantity and quality of final islet products. Donor body weight and BMI increased significantly over the period (p<0.001). Islet yield measures have improved with time including islet equivalent (IEQ)/particle ratio and IEQs infused. The average dose of islets infused significantly increased in the era of 2007-2010 when compared to 1999-2002 (445.4±156.8 vs. 421.3±155.4×0(3) IEQ; p<0.05). Islet purity and total number of ß cells significantly improved over the study period (p<0.01 and <0.05, respectively). Otherwise, the quality of clinical islets has remained consistently very high through this period, and differs substantially from nonclinical islets. In multivariate analysis of all recipient, donor and islet factors, and medical management factors, the only islet product characteristic that correlated with clinical outcomes was total IEQs infused. This analysis shows improvements in both quantity and some quality criteria of clinical islets produced over 1999-2010, and these parallel improvements in clinical outcomes over the same period.

The selective use of splenic flexure mobilization is safe in both laparoscopic and open anterior resections.

AIM: Splenic flexure mobilization (SFM) is standard practice in anterior resections. No previous studies have compared outcomes with and without SFM in laparoscopic and open colorectal cancer surgery. This study aimed to determine whether routine or selective SFM should be advised. METHOD: Data were collected prospectively on all elective anterior resections for cancer in our unit between October 2006 and November 2009. RESULTS: Of 263 resections, SFM data were recorded in 216; 138 were laparoscopic (32% with SFM, 3.6% converted) and 78 open (68% with SFM). Eighty-eight were low anterior resections (LARs) for mid-low rectal cancers, with 54 laparoscopic (50% with SFM) and 34 open (91% with SFM). Comparing laparoscopic with SFM to without, differences were found in the proportion of LARs (61%vs 29%, P<0.001), defunctioning ileostomy rates (75%vs 46%, P=0.001) and operative time (median 255 vs 185 min, P<0.001), with no differences in age, gender, body mass index, American Society of Anesthesiology score, preoperative treatment, length of stay, lymph node yield, conversion rate, mortality, anastomotic leakage, reoperation, readmission and R0 resection. No differences in outcomes were seen between laparoscopic LARs with and without SFM or between open resections with and without SFM. CONCLUSION: Our results show no disadvantage in short-term clinical or oncological outcomes when SFM was avoided. Laparoscopic anterior resections with SFM take longer. A selective approach to SFM is safe during anterior resection (open or laparoscopic), including mid-low rectal cancers.

Can we predict the spreading of a two-liquid system from the spreading of the corresponding liquid-air systems?

We present new data obtained from the spreading of a series of oil droplets, on top of a hydrophobic grafted silicon substrate, in air and immersed in water. We follow the contact angle and radius dynamics of hexane, dodecane, hexadecane, dibutyl phthalate, and squalane from the first milliseconds to approximately 1 s. Analysis of the images allows us to make several hundred contact angle and droplet radius measurements with great accuracy. The G-Dyna (Seveno et al. Langmuir 2010, 25, 13034) software is then used to fit the data with one of the wetting theories, the molecular-kinetic theory (MKT) (Blake et al. J. Colloid Interface Sci.1969, 30, 421), which takes into account the dissipation at the three-phase zone at the contact line. This theory allows us to extract the coefficient of friction of the contact line, which expresses the relationship between the driving force, that is, the unbalanced Young force, and the contact-line velocity V. It is first shown that the MKT is appropriate to describe the experimental data and then that the contact-line friction is a linear function of the viscosity as theoretically predicted. This is checked for oil-air and oil-water systems. A linear relation between the contact-line friction measured in oil-water systems and the contact-line frictions of the parent single liquid system seems plausible. To the best of our knowledge, this is the first trial to establish a link between the dynamics of wetting in liquid-liquid and in liquid-air systems.

Dynamics of wetting revisited.

We present new spreading-drop data obtained over four orders of time and apply our new analysis tool G-Dyna to demonstrate the specific range over which the various models of dynamic wetting would seem to apply for our experimental system. We follow the contact angle and radius dynamics of four liquids on the smooth silica surface of silicon wafers or PET from the first milliseconds to several seconds. Analysis of the images allows us to make several hundred contact angle and droplet radius measurements with great accuracy. The G-Dyna software is then used to fit the data to the relevant theory (hydrodynamic, molecular-kinetic theory, Petrov and De Ruijter combined models, and Shikhmurzaev's formula). The distributions, correlations, and average values of the free parameters are analyzed and it is shown that for the systems studied even with very good data and a robust fitting procedure, it may be difficult to make reliable claims as to the model which best describes results for a given system. This conclusions also suggests that claims based on smaller data sets and less stringent fitting procedures should be treated with caution.

Fourier transform infrared immunosensors for model hapten molecules.

We report experimental results concerning the detection of 2,4-dinitrophenol, under its free form or coupled to human serum albumin using Fourier transform infrared spectroscopy-based sensors. Competitive immunoreactions were carried out using several anti-dinitrophenol monoclonal antibodies. Comparison with enzyme-linked immunosorbent assays in competition is given for standard operating conditions. FTIR detection limits are comparable to those obtained by ELISA. The limits of detection are about 5-15 ng/mL for the coupled DNP. Using the LO-DNP61 antibody, a detection limit of congruent with 5 ng/mL was also estimated for the free DNP molecules but is much higher for the other antibodies.

Ligand-receptor interactions in complex media: a new type of biosensors for the detection of coagulation factor VIII.

Detection of receptor-ligand interaction in complex media remains a challenging issue. We report experimental results demonstrating the specific detection of the coagulation factor VIII in the presence of a large excess of other proteins using the new BIA-ATR technology based on attenuated total reflection Fourier transform infrared spectroscopy. The principle of the detection is related to the ability of factor VIII molecules to bind to lipid membranes containing at least 8% phosphatidylserine. Several therapeutic concentrates of factor VIII were analyzed and the binding of the coagulation factor was monitored as a function of time. We show that a non-specific adsorption of stabilizing agents (typically, von Willebrand factor and human serum albumin) may be avoided by controlling the geometry of the ATR element. A linear response of the sensors as a function of the factor VIII concentration is described for different lipid membrane compositions.

Superhydrophobic surfaces from various polypropylenes.

Superhydrophobic surfaces were prepared from solutions of isotactic polypropylenes of various molecular weights using soft chemistry. Varying the conditions of the experiments (polymer concentration and initial amount of the coated solution) allowed us to optimize the superhydrophobic behavior of the polymer film. Results show that decreasing the concentration and/or film thicknesses decreases the probability to get superhydrophobicity for all polypropylenes tested. Measurement and analysis of advancing and receding contact angles as well as estimation of surface homogeneity were performed. Similar results were obtained with syndio- as well as atactic polypropylenes.

Mock artery distension: comparison of optical, mechanical and theoretical results.

The relationship between the pressure inside a cylindrical mock vessel and the change in radius is called radial compliance. It has been postulated that it is the internal change in radius with pressure that has a significant effect on blood flow disturbance or the interaction of a graft or synthetic tube with an indwelling stent or catheter. A variety of techniques are widely used in determining this parameter. Some are direct measurements of the internal diameter and some methods measure the outer diameter along with the use of theoretical calculations in determining this parameter. It is essential to understand and evaluate all the techniques widely used in the cardiovascular industry. This research work is an effort towards making this comparison.

Linear elastic mechanics of mock arteries: empirical versus theoretically predicted pulsatile stent deflection.

Evaluation of a medical device requires human or animal studies to be conducted. In the past decade, the use of mock arteries or mock vessels has found its place in the cardiovascular industry as a best alternative to researchers. Mechanical characteristics of the mock artery play a significant role on the stent and vascular grafts being tested. It is these mechanical characteristics that determine the amount of load applied on the medical device thus deciding the validity of the fatigue test on the devices. This paper is an effort towards determining the distension of the mock artery and relating it to the distension of the vascular stent.

Contact-line friction of liquid drops on self-assembled monolayers: chain-length effects.

The static and dynamic wetting properties of self-assembled alkanethiol monolayers of increasing chain length were studied. The molecular-kinetic theory of wetting was used to interpret the dynamic contact angle data and evaluate the contact-line friction on the microscopic scale. Although the surfaces had a similar static wettability, the coefficient of contact-line friction zeta0 increased linearly with alkyl chain length. This result supports the hypothesis of energy dissipation due to a local deformation of the nanometer-thick layer at the contact line.

Biochemical interaction analysis on ATR devices: a wet chemistry approach for surface functionalization.

A new generic device suitable for the investigation of ligand-receptor interactions is presented. In particular, the research focused on optical waveguides constituted by an attenuated total internal reflection (ATR) element, transparent in the infrared and whose surfaces were activated in view of covalently binding a receptor. Silicon and germanium ATR elements were considered. The original method is based on the grafting of bifunctional spacer molecules directly at the surface of the germanium crystal, avoiding the deposition of an intermediate metal layer. The grafting of these binding molecules (under their N-hydroxysuccinimidyl ester forms) was performed either by wet chemistry or by photochemistry. The functionalized surfaces, which allow the binding of molecules bearing peripherical NH2 groups, were successfully used, e.g., for the detection of proteins (streptavidin) or of small molecules (biotin). In the latter case, the biotin was readily detected for concentrations as low as 10(-12) M.

Single versus double ended high frequency pressurization of mock arteries: symmetry of expansion.

A series of experiments was carried out to evaluate the expansion characteristics of silicone mock arteries at frequencies from 5 to 100 Hz. Of particular interest was the magnitude of expansion along the length of the tube versus frequency. The tubes were pressurized from one end or from both ends. In general, results indicate asymmetric expansion along the length of the tube. This asymmetry, however, changed dramatically with frequency. These changes are not fully explainable by standard experimental considerations such as compliance and harmonics.

Uso de fixador esquelético externo tipo I para osteossíntese de tibiotarso em galinhas da raça Plymouth Rock Branca Modelo experimental para uso em aves selvagens / The use of type I external skeletal fixer for osteosynthesis of tibiotarsus in white plymouth rock chickens experimental model for the use in wild birds / Alteraciones morfológicas en los órganos genitales de perros y gatos provenientes de villas rurales de la región de umuarama ­ pr

Este estudo avaliou a eficiência do fixador esquelético externo, tipo I, para o tratamento de fratura de tibiotarso em oito galinhas adultas da raça Plymouth Rock Branca. As aves foram pré-anestesiadas com sulfato de morfina e anestesiadas com halotano. Em seguida, foi realizada fratura na diáfise do tibiotarso esquerdo, por meio de serra oscilatória. Quatro pinos de Kirschner foram inseridos por meio das corticais ósseas, dois proximalmente e dois distalmente do foco da fratura. Após a redução da fratura, os pinos foram conectados externamente por meio de uma barra de acrílico autopolimerizável, na face lateral externa do membro. O retorno da capacidade de utilização do membro foi observado em 24,00 + ou - 16,42 dias, e a cicatrização óssea ocorreu em 40,37 + ou - 11,80 dias. Em três aves (37,5%) observou-se deslocamento dos pinos, o que levou a claudicação persistente até o final do experimento, no 60º dia de pós-operatório. Os resultados do experimento demonstraram que redução aberta e aplicação de fixador esquelético externo, tipo I, não é um método totalmente efetivo para o tratamento de fraturas de tibiotarso em galinhas da raça Plymouth Rock Branca e não deve ser indicado, pois pode promover migração dos pinos e desestabilização da fratura.

ABSTRACT: This study evaluated the effi ciency of the type I external skeletal fi xer for the treatment of tibiotarsus fracture in eight adult White Plymouth Rock chickens. The birds were pre-anesthetized with morphine sulfate and anesthetized with halothane, and submitted to a diaphisary fracture in the left tibiotarsus, performed with an oscillatory saw. Four Kirschner wires were inserted through the bone cortices, being two proximally and two distally to the fracture. After the fracture reduction the wires were externally connected by a bar of auto polymerizing acrylic resin, in the external lateral face of the member. The return to the capacity to use the member was observed in 24.00 ± 16.42 days, and the bone healing occurred in 40.37 ± 11.80 days. In three individuals (37.5%) there was observed wire displacement, leading to lameness which persisted until the end of the research, 60 days after the surgery. The results of this study showed that open reduction and the use of type I external skeletal fi xer is not a totally effective method for the treatment of tibiotarsus fractures in White Plymouth Rock chickens, causing dislocation of the wires and disestablishment of the fracture

RESUMEN: En este estudio se evaluó la efi cacia del fi jador esquelético externo tipo I para el tratamiento de fractura de tibiotarso en ocho gallinas adultas de la raza Plymouth Rock Blanca. Las aves fueron preanestesiadas con sulfato de morfi na y anestesiadas con halotano, y sometidas a una fractura diafi sária en el tibiotarso izquierdo, con una sierra oscilatoria. Se insertaron cuatro pinos de Kirschner a través de las corticales del hueso, siendo dos en posición proximal y dos en posición distal a la fractura. Después de la reducción de la fractura los pinos fueron conectados externamente por una pieza de resina acrílica de auto polimerización, en la parte lateral externa del miembro. Se observó retorno de la capacidad de uso del miembro en 24,00 ± 16,42 días, y cicatrización del hueso en 40,37 ± 11,80 días. En tres individuos (37,5%) se observó desplazamiento de los pinos, llevando a claudicación que persistió hasta el fi nal de la investigación, 60 días después de la cirugía. Los resultados de este estudio mostraron que reducción abierta y uso de fi jador esquelético externo tipo I no es un método totalmente efi caz para el tratamiento de fracturas de tibiotarso en gallinas de la raza Plymouth Rock Blanca, causando dislocación de los pinos y desestabilización de la fractura