Evaluation of the Safety and Efficacy of a Novel Thrombin Containing Combination Hemostatic Powder Using a Historical Control.

This clinical study compares 2 hemostatic agents, a novel combination powder (CP) (HEMOBLAST™ Bellows) and an established polysaccharide starch powder (PP) (Arista™ AH) to assess the usefulness of CP. Retrospective comparative analysis of CP (July 2018 to July 2019, 68 patients) to PP (January 2011 to January 2013, 94 patients) in cardiothoracic patients was performed using linear regression models adjusting for age, sex, and procedure type for the endpoints: blood loss; protamine to skin closure time (hemostasis time); chest tube output and blood products required 48 hours postoperatively; ICU stay; postoperative comorbidities; and 30 day mortality. 162 patients (108 M: 54 F) underwent 162 cardiothoracic surgical procedures including: transplantation (n = 44), placement of ventricular assist device (n = 87), and others (n = 31). Use of CP compared to PP (Estimated Mean Difference [95% CI], P-value) produced significant reductions: blood loss (mL) (-886.51 [-1457.76, -312.26], P = 0.003); protamine to skin closure time (min) (-16.81 [-28.03, -5.59], P = 0.004); chest tube output (48 hrs, mL) (-445.76 [-669.38, -222.14], P < 0.001); packed red blood cell transfusions (units) (-0.98 [-1.56, -0.4], P = 0.001); and postoperative comorbidities (-0.31 [-0.55, -0.07], P = 0.012). There were no differences in the ICU stay (4.07 [-2.01, 10.15], P = 0.188) or 30-day mortality (0.57 [0.20, 1.63], P = 0.291). The use of CP in complex cardiothoracic operations resulted in improved hemostasis and significant clinical benefits in blood loss, transfusion requirements, morbidity, and time in operating room.

SPOT GRADE II: Clinical Validation of a New Method for Reproducibly Quantifying Surgical Wound Bleeding: Prospective, Multicenter, Multispecialty, Single-Arm Study.

The SPOT GRADE (SG), a Surface Bleeding Severity Scale, is a unique visual method for assessing bleeding severity based on quantitative determinations of blood flow. This study assessed the reliability of the SG scale in a clinical setting and collected initial data on the safety and efficacy of HEMOBLAST Bellows (HB), a hemostatic agent, in abdominal and orthopedic operations. Twenty-seven patients were enrolled across 3 centers and received the investigational device. Bleeding severity and hemostasis were independently assessed by 2 surgical investigators at baseline and at 3, 6, and 10 minutes after application of HB and compared for agreement. The mean paired κ statistic for assignment of SG scores was .7754. The mean paired κ statistics for determining eligibility for participation in the trial based on bleeding severity and the mean paired κ statistics determining the presence of hemostasis were .9301 and .9301, respectively. The proportion of patients achieving hemostasis within 3, 6, and 10 minutes of HB application were 50.0%, 79.2%, and 91.7%, respectively. There were no unanticipated adverse device effects and one possible serious adverse device effect, as determined by the Independent Data Monitoring Committee (IDMC). The reliability of the SG scale was validated in a clinical setting. Initial data on the safety and efficacy of HB in abdominal and orthopedic operations were collected, and there were no concerns raised by the investigators or the IDMC.

An immediate access dialysis graft designed to prevent needle-related complications: Results from the initial pre-clinical studies.

INTRODUCTION: No technology has been specifically developed with the intent to reduce needle-related vascular access injuries; a significant source of complications and abandonment. We present the initial pre-clinical study results of a novel, self-sealing, immediate cannulation dialysis graft that aims to prevent needle-related complications; to promote safe, reliable needle access; to reduce catheter use; and could facilitate home hemodialyisis. METHODS: The innovative graft design consists of two cannulation chambers with self-sealing properties and materials that prevent side and back wall needle puncture. Study and control grafts (expanded polytetrafluoroethylene) were implanted in one pig and 10 sheep in two studies over the course of 1 year. First cannulation occurred immediately post implant for all study grafts. Post-cannulation time to hemostasis, hematoma and seroma formation, infection, and patency were recorded. RESULTS: The two studies account for nearly 60 weeks (average 6.4 weeks/graft) of study graft follow-up. In the ovine study, average study graft time to hemostasis was 27.3 s (standard deviation = 26.3, range = 0-120), and the control averaged 177.2 s (standard deviation = 113.4, range = 60-600), p < 0.0001. Secondary patency was 75% and 67% for the study and control grafts, respectively. Neither study nor control groups experienced seroma, graft infections, or deaths. DISCUSSION: All novel grafts in the studies were implanted successfully and functioned as intended. There were no complications related to tunneling of the study graft and the chamber prevented back/side wall needle injury. This novel technology may help to mitigate these needle-related complications, while allowing for early/immediate cannulation which could also reduce catheter contact time.

Prospective, multicenter, randomized, controlled trial evaluating the performance of a novel combination powder vs hemostatic matrix in cardiothoracic operations.

AIM: This trial compared the hemostatic performance of a novel combination powder (CP) to a control hemostatic matrix (HM) in cardiothoracic operations. METHODS: Patients meeting eligibility criteria were enrolled after providing informed consent. Subjects were randomized intraoperatively to receive CP (HEMOBLAST Bellows; Biom'up, France) or HM (FLOSEAL Hemostatic Matrix; Baxter Healthcare Corporation, Hayward, CA). Bleeding was assessed using a clinically validated, quantitative bleeding severity scale. The primary endpoint was total time to hemostasis (TTTH), from the start of device preparation, as an indicator of when a surgeon asks for a surgical hemostat until hemostasis was achieved. TTTH at 3 minutes was utilized for the primary analysis, while TTTH at 5 minutes was considered as a secondary endpoint. RESULTS: A total of 105 subjects were enrolled across four institutions. The primary efficacy endpoint for the superiority of CP relative to HM for success at achieving hemostasis within 3 minutes was met, with 64.2% of the CP group achieving hemostasis compared with 9.6% of the HM group, a difference of 54.54% (37.4%-71.6%; P < .001 for superiority). The secondary efficacy endpoint was also met, with 92.5% of the CP group achieving hemostasis at 5 minutes versus 44.2% in the HM group, a difference of 48.2% (31.1%-65.4%; P < .001 for noninferiority). There were no device-related adverse events. CONCLUSIONS: In this multicenter, randomized, controlled trial, comparison of CP to HM revealed CP superiority and noninferiority for TTTH at 3 and 5 minutes, respectively.

Objective Assessment of the Early Stages of the Learning Curve for the Senhance Surgical Robotic System.

OBJECTIVE: The purpose of this research is to study the early stages of the Senhance learning curve to report how force feedback impacts learning rate. This serves as an exploratory investigation into assumptions that fellows and faculty will adjust faster to the Senhance in comparison with residents, and that force feedback will not hinder skill acquisition. DESIGN: In this study, participants completed the peg transfer and precision cutting task from the Fundamentals of Laparoscopic Surgery (FLS) manual skills assessment five times each using the Senhance while instrument motion was tracked. SETTING: This study took place in the Surgical Education and Activities Laboratory at Duke University Medical Center. PARTICIPANTS: Participants for this study were residents, fellows, and faculty from Duke University Medical Center in general surgery and gynecology specialties (N = 16). RESULTS: Postulated linear mixed effects models with participant level random effects showed significant improvement with additional attempts for the peg transfer task after adjusting for surgical experience and force feedback respectively for the primary FLS score metric. The secondary metric of total instrument path length also showed improvement (significant decreases) in path length with additional attempts after respectively adjusting for surgical experience and force feedback. CONCLUSIONS: This study investigates the early stages of the learning curve of the Senhance. Exploratory modeling indicates that residents, fellows, and faculty surgeons rapidly adapt to the controls of the Senhance regardless of experience level and force feedback engagement. The results from this study may serve as motivation for future prospective studies that achieve sufficient statistical power with a larger sample size and strict experimental design.

Thromboembolic Events with Enterprise Versus Pipeline: Porcine In Vivo Experiment.

BACKGROUND: Thromboembolic complications are serious adverse events associated with stenting of intracranial aneurysms. For the development of novel devices, currently no practical model exists to evaluate distal embolic events. The purpose of the current study was 2-fold: 1) assess the feasibility of a porcine carotid bifurcation model for in vivo testing of stent thrombogenicity and 2) compare the thrombogenicity of the Enterprise vascular reconstruction device versus the Pipeline embolization device (PED). METHODS: Six Yorkshire pigs underwent implantation of size-matched devices across the carotid bifurcation. Each animal received 1 Enterprise and 1 PED contralaterally. Baseline and 2-week follow-up angiography were performed. Images were analyzed including detailed measurements of the rete mirabile, a small-vessel conglomerate supplied by branches of the common carotid artery. RESULTS: In the absence of thromboembolic events at 2 weeks (n = 8), the perfused rete area measured 134.4 ± 6.9 mm2. In the presence of thromboembolic events (n = 4), the perfused rete was reduced to an area covering 37.1 ± 8.6 mm2 (P < 0.01). There was no difference in thrombogenicity between Enterprise and PED with a thromboembolic event rate of 33.3% for both devices (P > 0.99). CONCLUSION: The swine carotid stent model allows in vivo analysis of device-related thrombogenicity and distal embolic event rates. Size reduction of the perfused rete mirabile indicates the presence of thromboembolic events. Both Enterprise and PED were associated with similar thrombogenicity in this experiment.

Sample Entropy of Speed Power Spectrum as a Measure of Laparoscopic Surgical Instrument Trajectory Smoothness.

In this study the complexity of the speed power spectrum is assessed as a metric for measuring trajectory smoothness. There are a variety of published methods for analyzing trajectory smoothness but many lack validity. This preliminary study took an information theoretic approach to assess trajectory smoothness by applying the sample entropy measure to the speed power spectrum of simulated and experimental trajectories. The complexity measurements of the speed power spectrum were compared to a traditional jerk-based measure of trajectory smoothness, namely $\log $-dimensionless jerk. The approach was first tested on basic simulated shape tracings with varying locations of sporadic movement, simulated as Gaussian noise. This method was duplicated in an experimental setting with the same shapes and locations of sporadic movement by capturing the trace trajectories using an electromagnetic motion tracking system. Finally, this approach was applied to kinematic data of laparoscopic surgical instrument tips, captured over 105 iterations of a basic surgical task. Analysis from all three testing scenarios showed that there is a statistically significant linear correlation between $\log $-dimensionless jerk and the sample entropy of speed power spectra.

A novel paraplegia model in awake behaving macaques.

Lower limb paralysis from spinal cord injury (SCI) or neurological disease carries a poor prognosis for recovery and remains a large societal burden. Neurophysiological and neuroprosthetic research have the potential to improve quality of life for these patients; however, the lack of an ethical and sustainable nonhuman primate model for paraplegia hinders their advancement. Therefore, our multidisciplinary team developed a way to induce temporary paralysis in awake behaving macaques by creating a fully implantable lumbar epidural catheter-subcutaneous port system that enables easy and reliable targeted drug delivery for sensorimotor blockade. During treadmill walking, aliquots of 1.5% lidocaine with 1:200,000 epinephrine were percutaneously injected into the ports of three rhesus macaques while surface electromyography (EMG) recorded muscle activity from their quadriceps and gastrocnemii. Diminution of EMG amplitude, loss of voluntary leg movement, and inability to bear weight were achieved for 60-90 min in each animal, followed by a complete recovery of function. The monkeys remained alert and cooperative during the paralysis trials and continued to take food rewards, and the ports remained functional after several months. This technique will enable recording from the cortex and/or spinal cord in awake behaving nonhuman primates during the onset, maintenance, and resolution of paraplegia for the first time, thus opening the door to answering basic neurophysiological questions about the acute neurological response to spinal cord injury and recovery. It will also negate the need to permanently injure otherwise high-value research animals for certain experimental paradigms aimed at developing and testing neural interface decoding algorithms for patients with lower extremity dysfunction.NEW & NOTEWORTHY A novel implantable lumbar epidural catheter-subcutaneous port system enables targeted drug delivery and induction of temporary paraplegia in awake, behaving nonhuman primates. Three macaques displayed loss of voluntary leg movement for 60-90 min after injection of lidocaine with epinephrine, followed by a full recovery. This technique for the first time will enable ethical live recording from the proximal central nervous system during the acute onset, maintenance, and resolution of paraplegia.

Tissue engineered vascular grafts: Origins, development, and current strategies for clinical application.

Since the development of a dependable and durable synthetic non-autogenous vascular conduit in the mid-twentieth century, the field of vascular surgery has experienced tremendous growth. Concomitant with this growth, development in the field of bioengineering and the development of different tissue engineering techniques have expanded the armamentarium of the surgeon for treating a variety of complex cardiovascular diseases. The recent development of completely tissue engineered vascular conduits that can be implanted for clinical application is a particularly exciting development in this field. With the rapid advances in the field of tissue engineering, the great hope of the surgeon remains that this conduit will function like a true blood vessel with an intact endothelial layer, with the ability to respond to endogenous vasoactive compounds. Eventually, these engineered tissues may have the potential to supplant older organic but not truly biologic technologies, which are used currently.

Estudio Multicéntrico Nacional. Análisis de las complicaciones de colonoscopías realizadas por coloproctólogos / National Multicentric Study. Analysis of complications of colonoscopy performed by colorectal surgeons

Introducción: la colonoscopía es el método estándar para el diagnóstico y tratamiento de la patología colorrectal. Su incidencia a nivel nacional entre los cirujanos es desconocido. Objetivo: analizar las complicaciones de la videocolonoscopía en series institucionales. Pacientes y Métodos: se analizaron las videocolonoscopías realizadas entre enero 2009 y diciembre de 2010 Variables: complicaciones, patología previa, sexo y edad, indicación, tipo de endoscopía, complicación, número y sitio de la complicación, clínica, metodología y momento del diagnóstico, tratamiento y evaluación de complicaciones. Resultados: de 6629 colonoscopías, el 58% fueron del sexo femenino. Hubo un 94,7% de llegadas al ciego. El tiempo fue de 28,7’ (20’-45’). La edad promedio fue de 53,5 años (13-92). Fueron ambulatorias en el 90,1%. Se hicieron 4057 (61,2%) estudios diagnósticos y 2572 (38,8%) terapéuticos. Se registraron 17 lesiones (0,25%), 12 (0,18%) estaban relacionadas al procedimiento. Las complicaciones luego de colonoscopías diagnósticas fueron del 0,12% y del 0,31% en procedimientos terapéuticos. Las complicaciones fueron resueltas con expectación en 4, cirugía en 7 y endoscopia en 1. No hubo mortalidad ni morbilidad asociadas. Existieron resultados similares entre los diferentes centros participantes. Discusión: la incidencia de complicaciones, luego de colonoscopía, fue baja. Las más frecuentes fueron la perforación y la hemorragia. La incidencia fue similar tanto en estudios diagnósticos como en terapéuticos. Fue evidente que cuando el diagnóstico fue precoz y el tratamiento oportuno, la morbi-mortalidad fue baja o nula. La relación de equivalencia de resultados entre centros de referencia y centros del interior infiere que la calidad del estudio fue similar entre ambos. Cuando se considera que fueron entrenados en centros similares al de referencia es dable atribuir a la colonoscopía realizada por coloproctólogos los mismos resultados... (TRUNCADO).

Background: colonoscopy is diagnostic standard of colorectal diseases. Its adoption by proctologists is unknown. Objective: to analyze nationwide colonoscopic complications performed by colorectal surgeons. Method: all colonoscopies performed between January 2009 and December 2010 were analyzed by type of colonoscopy and complication, previous pathology, age and gender, number and site of complication, diagnosis and treatment. Results: 6629 colonoscopies were performed, 58% of them were female. Cecum visualization was possible in almost 95% in 20 to 45 minutes. Average age was 53,5 years. Almost 91% were ambulatory. 62% of them were diagnostic procedures. There were 17 complications, 12 after diagnostic procedures. Complications were treated by expectation in 4 and surgery in 7. There was neither morbidity nor mortality in this series. Similar results were found in different centers. Discussion: incidence of complications after colonoscopy is low. Perforation and hemorrhage are the most frequent and its incidence is similar in diagnostic and therapeutic scopes. In early diagnosis, morbidity and mortality were lower. Relation of incidence between high and low volume hospitals were similar, even between colorectal surgeons with same results. Conclusion: colonoscopy is a safe procedure performed by colorectal surgeons, either diagnostic or therapeutic, supported for the first time by nationwide data.

Arteriovenous fistula creation using the Optiflow vascular anastomosis device: a first in man pilot study.

Although arteriovenous fistulae are the preferred form of dialysis vascular access they continue to have significant problems with maturation failure. The Optiflow device is a sutureless anastomotic conduit which could potentially reduce surgical time and also standardize the surgical procedure. We report herein on the "First in Man" experience with the Optiflow device.

Tissue-engineered vascular grafts: autologous off-the-shelf vascular access?

Dialysis grafts have provided reliable access for millions of patients in need of renal replacement therapy. However, regardless of the material used for artificial dialysis grafts their mean patency remains generally poor and infection rates are greater than native arteriovenous fistulas. The need for superior alternatives to conventional synthetic materials used for vascular access has been an area of investigation for more than 25 years and recently there has been a great deal of progress in the field of tissue-engineered vascular grafts. Many of these technologies are either commercially available or are now entering early phases of clinical trials. This review briefly covers the history, potential advantages, and disadvantages of these technologies, which are likely to create an impact in the field of vascular access surgery.

Colonoscopías por cirujanos especialistas: ¿Qué opinan los coloproctologos? Resultados de una encuesta / Colonoscopy by surgeons. What do colorectal surgeons think. Results of a national survey

Introducción: la colonoscopía constituye el método estándar actualmente para el diagnóstico y tratamiento de la patología colorrectal. Su realización por proctólogos o gastroenterólogos es tema de debate. Objetivo: Analizar distintos aspectos sobre la colonoscopía por proctólogos entre los miembros de la Sociedad Argentina de Coloproctología (SACP). Diseño: Análisis de encuesta. Lugar de Aplicación: Sector Coloproctología. Institución Privada Universitaria. Método: se realizo una encuesta de opción múltiple entre todos los miembros titulares de la SACP. No hubo rechazos y la encuesta estaba completa en todos los casos. No se excluyo ninguna respuesta. Total: 60 encuestas. Resultados: Todos excepto 6 realizan Videocolonoscopias. Realizaron su formación en hospitales privados, residencia o en su trabajo. El número de colonoscopias en su entrenamiento fue: 27 sin respuesta, <100 (17), 100 (6), 200 (4) y > 200 (4). En 9 casos las hace sólo el cirujano, en 21 el clínico y en 32, ambos. En 20 casos son endoscopias diagnósticas; los restantes hacen Polipectomías (38), esclerosis y dilatación (27) y endoprótesis (12). Solo 39 usan anestesista. En 52 es ambulatorio o de corta estadía. En 23 casos no documentan el estudio; 10 no archivan los informes; 24 casos no usan consentimiento, 3 creen que no debe formar parte de la especialidad y que su formación no debe ser regulada por la SACP. De los mayores de 60 años, solo 4 hacen colonoscopias, mientras que en los menores sólo 5 no la realizan. Discusión: la colonoscopia continúa su desarrollo como método terapéutico ampliando sus indicaciones e incorporando nuevas técnicas como la disección endoscopía submucosa, mucosectomía, etc. Los cirujanos colorrectales deben incorporar estas técnicas desde su formación. No todos los consultados realizan colonoscopías terapéuticas. No es unánime aún la opinión entre los miembros consultados sobre quién debe idealmente realizar el estudio... (TRUNCADO)

Backgroud: colonoscopy is a standard diagnostic and therapeutic method for colorrectal disease. Wether or not it should be performed by colorrectal surgeons remains in question. Objective: to analyze several aspects about colonoscopy by surgeons between members of Argentinean Society of Coloproctology (ASC). Design: survey. Setting: Colorectal Sector. Private Universitary Institution. Method: a national survey between members of ASC had been performed. There were no rejections. The survey was answered completely in all cases. Neither question nor ítem were refused. There were 60 answers. Results: All surgeons but 6 do perform colonoscopy. They had been trained in private institutions, residency program or in their actual job. The volume of endoscopies during their training was: 27 did not answer, 17 did fewer than 100, 6 about 100, 4 did 200 and 4 more than 200. In 9 cases colonoscopies are performed by surgeons, 21 by clinic and 32 both. In 20 cases are diagnostic endoscopies, the others are polipectomies (38), sclerosis, dilatation (27) and colorectal stents in 12. Only 39 of them use anesthesiology. The procedure was ambulatory in 52. There was not any document of the procedure in 10, no informed consent in 24, 3 of them do not believed that it should be a part of specialty and without rules from the ASC. Discussion: colonoscopy move forward as therapeutic and diagnostic standard method, with more indications, technology, etc. Colorectal surgeons must have this training in his background. There is no uniform thinking between members about who should do this procedure. Conclusions: most of surgeons consider that colonoscopy should be taught during residency and become major subject in Specialty. It shall be a part of general surgery program as well and shall be monitorized by our Society.

An early study on the mechanisms that allow tissue-engineered vascular grafts to resist intimal hyperplasia.

Intimal hyperplasia is one of the prominent failure mechanisms for arteriovenous fistulas and arteriovenous access grafts. Human tissue-engineered vascular grafts (TEVGs) were implanted as arteriovenous grafts in a novel baboon model. Ultrasound was used to monitor flow rates and vascular diameters throughout the study. Intimal hyperplasia in the outflow vein of TEVGs was assessed at the anastomosis and at juxta-anastomotic regions via histological analysis, and was compared to intimal hyperplasia with polytetrafluoroethylene (PTFE) grafts in the baboon model and in literature reports from other animal models. Less venous intimal hyperplasia was observed in histological sections with arteriovenous TEVGs than with arteriovenous PTFE grafts. TEVGs were associated with a mild, noninflammatory intimal hyperplasia. The extent of intimal tissue that formed with TEVG placement correlated with the rate of blood flow through tissue engineered vascular grafts at 2 weeks postimplant. Outflow vein dilatation was observed with increased flow rate. Both mid-graft flow rates and outflow vein diameters reached a plateau by week 4, which suggested that venous remodeling and intimal hyperplasia largely occurred within the first 4 weeks of implant in the baboon model. Given their compliant and noninflammatory nature, TEVGs appear resistant to triggers for venous intimal hyperplasia that are common for PTFE arteriovenous grafts, including (1) abundant proinflammatory macrophage populations that are associated with PTFE grafts and (2) compliance mismatch between PTFE grafts and the outflow vein. Our findings suggest that arteriovenous TEVGs develop only a mild form of venous intimal hyperplasia, which results from the typical hemodynamic changes that are associated with arteriovenous settings.

Decellularized tissue-engineered blood vessel as an arterial conduit.

Arterial tissue-engineering techniques that have been reported previously typically involve long waiting times of several months while cells from the recipient are cultured to create the engineered vessel. In this study, we developed a different approach to arterial tissue engineering that can substantially reduce the waiting time for a graft. Tissue-engineered vessels (TEVs) were grown from banked porcine smooth muscle cells that were allogeneic to the intended recipient, using a biomimetic perfusion system. The engineered vessels were then decellularized, leaving behind the mechanically robust extracellular matrix of the graft wall. The acellular grafts were then seeded with cells that were derived from the intended recipient--either endothelial progenitor cells (EPC) or endothelial cell (EC)--on the graft lumen. TEV were then implanted as end-to-side grafts in the porcine carotid artery, which is a rigorous testbed due to its tendency for graft occlusion. The EPC- and EC-seeded TEV all remained patent for 30 d in this study, whereas the contralateral control vein grafts were patent in only 3/8 implants. Going along with the improved patency, the cell-seeded TEV demonstrated less neointimal hyperplasia and fewer proliferating cells than did the vein grafts. Proteins in the mammalian target of rapamycin signaling pathway tended to be decreased in TEV compared with vein grafts, implicating this pathway in the TEV's resistance to occlusion from intimal hyperplasia. These results indicate that a readily available, decellularized tissue-engineered vessel can be seeded with autologous endothelial progenitor cells to provide a biological vascular graft that resists both clotting and intimal hyperplasia. In addition, these results show that engineered connective tissues can be grown from banked cells, rendered acellular, and then used for tissue regeneration in vivo.

Readily available tissue-engineered vascular grafts.

Autologous or synthetic vascular grafts are used routinely for providing access in hemodialysis or for arterial bypass in patients with cardiovascular disease. However, some patients either lack suitable autologous tissue or cannot receive synthetic grafts. Such patients could benefit from a vascular graft produced by tissue engineering. Here, we engineer vascular grafts using human allogeneic or canine smooth muscle cells grown on a tubular polyglycolic acid scaffold. Cellular material was removed with detergents to render the grafts nonimmunogenic. Mechanical properties of the human vascular grafts were similar to native human blood vessels, and the grafts could withstand long-term storage at 4 °C. Human engineered grafts were tested in a baboon model of arteriovenous access for hemodialysis. Canine grafts were tested in a dog model of peripheral and coronary artery bypass. Grafts demonstrated excellent patency and resisted dilatation, calcification, and intimal hyperplasia. Such tissue-engineered vascular grafts may provide a readily available option for patients without suitable autologous tissue or for those who are not candidates for synthetic grafts.

Ligadura interesfintérica del trayecto fistuloso (LIFT): nuevo abordaje para el tratamiento de las fístulas anales complejas / LIFT: Ligation of Intersphincteric Fistula Tract: new approach in surgical treatment of complex anal fistula

Introducción: el tratamiento de la fístula perianal compleja es un desafío para el especialista. No existe una técnica de elección, dado sus incidencias variables de recidiva o incontinencia anal. Objetivo: presentar una técnica recientemente publicada para el tratamiento de las fístulas perianales complejas, cuya aplicación iniciamos en nuestra institución (LIFT-ligadura interesfintérica del trayecto fistuloso). Diseño: nota técnica. Lugar de Aplicación: Sector Coloproctología. Institución Privada Universitaria. Método: según la descripción original el procedimiento consiste en la ligadura y sección del trayecto fistuloso luego de ser identificado en el espacio interesfintérico sin dividir el esfínter anal. Conclusiones: las potenciales ventajas de este procedimiento incluyen: preservación de la anatomía del complejo esfinteriano evitando la sección del esfínter anal, mejores resultados funcionales (hasta la fecha sin impacto en la incontinencia según la literatura), es simple técnicamente, de bajo costo y se puede realizar nuevamente en caso de recidiva sin mayores inconvenientes. Tiene resultados similares y aún mejores que las técnicas conocidas. Es importante establecer el impacto en la continencia anal y la recidiva a largo plazo.

Background: treatment of fistula-in-ano is one of the most challenging experiences for the colorectal surgeon in benign anal surgery. There is none standard technique because of recurrence and incontinence index. Objective: To introduce a novel technique recently published to treat complex anal fistula: LIFT (ligation of the intersphineteric fistula tract). We initiated our experience in this procedure at our institution. Setting: Colorectal Unit, Sanatorio Modelo, Tucumán. Design: Technical note. Methods: according original paper, the surgeon ligates and divides fistula tract after its identification with a probe. Caution must be taking to avoid damage to anal sphincter when intersphincteric groove is accessed. Conclusion: potential advantages of this procedure are: sphincter saving technique, similar results and recurrence rates with other techniques, it is easy to do and to learn, low cost, better functional outcome and yet without incontinence reports. Comparative and long follow-up trials are needed to establish real advantages in surgical treatment of anal fistula.

Hemorragia rectocolónica aguda masiva secundaria a colitis ulcerosa asociada a lipodistrofía mesentérica colónica / Mesenteric lipodystrophy associated to ulcerative colitis: case report

Mesentenc lipodystrophy is part of a spectrum of idiopathic primary inflammatory and fibrotic processes that affect the mesentery. Pathophysiologically, these processes may affect the integrity of the gastrointestinal lumen and mesenteric vessels by a mass effect. We report a 64 year old male with an ulcerative colitis who consulted in the emergency room due to hematochezia. The computed tomography revealed a marked mesenteric thickening and colon and rectal wall lesions. The patient was subjected to a proctocolectomy with a good postoperative evolution.

La lipodistrofía mesentérica es una enfermedad inflamatoria crónica inespecífica progresiva que afecta el tejido adiposo del intestino delgado (mesenterio) o del mesocolon. Su etiología es idiopática y su fisiopatología permanece incierta. La lipodistrofía mesentérica con compromiso colorrectal es una condición muy poco frecuente y su asociación a colitis ulcerosa es aún mßs rara. No hemos encontrado ningún reporte previo en la literatura. Se comunica un caso de lipodistrofía colorrectal asociada a colitis ulcerosa que se presentó con sangrado digestivo bajo agudo masivo.

Tratamiento quirúrgico de la fístula anal: análisis de nuestra experiencia / Surgical treatment of anal fistula: analysis of our experience

Introducción: las fistulas perianales tienen una incidencia de 1/10000, son más frecuentes en varones jóvenes. Su tratamiento es complejo debido a la posibilidad de recidiva e incontinencia anal. Objetivo: analizar la morbilidad y los resultados inmediatos y alejados, en pacientes operados por fistula perianal. Diseño: retrospectivo. Serie consecutiva. Período: 2000-2007. Población: 168 casos consecutivos intervenidos quirúrgicamente en forma electiva. Lugar de aplicación: sector coloproctología. Institución Privada Universitaria. Método: variables: edad, sexo, etiología, técnica quirúrgica, patología asociada, morbilidad inmediata y alejada. Incontinencia (SCORE CCF-Cleveland Clinic Florida). Resultado: Edad: 48 años (15-71). Sexo 3/1 (H-M). la etiología fue: criptoglandular 94%, enfermedad de Crohn 1,2 %, cuerpo extraño 2,4 %, posthemorroidectomia 1,2%, postepisiotomía 0,6 %, postesfinterotomía lateral 0,6%. Según tipo, fístulas simples 71,4% y complejas 28,6%. Las técnicas quirúrgicas utilizadas fueron, fistulotomía 71%, sedal 11,3%, descenso mucoso 17%. El 56% presentaron patología anal asociada: hemorroides 45%, fisura 4,7% estenosis anal 5,9%. El seguimiento fue posible en el 80,9%. Recidivaron 9 casos. La incontinencia inmediata fue del 27,9% y alejada en fístulas simples 1,2% y en complejas 11%. Conclusiones: la etiología fue principalmente criptoglandular. Las técnicas más utilizadas fueron la fistulotomía y el descenso mucoso, esta última con menor índice de recidiva. La morbilidad fue baja. El índice de incontinencia fue variable y estuvo relacionado con la complejidad de la fístula y el tratamiento realizado. Se registraron casos de incontinencia alejada únicamente en las fístulas complejas.