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Resumen Introduccion La invasion macrovascular (IMV) en los pacientes con carcinoma hepatocelular (CHC) es un factor de muy mal pronostico. El tratamiento de estos casos es todavia controvertido. El objetivo de este estudio es valorar los resultados a corto y a largo plazo de la reseccion hepatica asociada a trombectomia en una serie de pacientes con CHC asociado a IMV. Metodos Estudio retrospectivo de cohortes en los pacientes sometidos a reseccion hepatica por CHC durante el periodo 2007-2015 (n = 120). Del total, 108 pacientes no presentaban IMV, mientras 12 presentaban al diagnostico IMV: 1 paciente presentaba IMV en la porta comun (Vp4), 8 pacientes en ramas portales de primer orden (Vp3), 1 paciente en ramas sectoriales (Vp2), 1 paciente en ramas segmentarias (Vp1), y ademas 1 paciente presentaba trombosis en una vena suprahepatica principal hasta la entrada en vena cava (Vv2). Resultados Los pacientes con IMV necesitaron con mayor frecuencia una hepatectomia mayor frente a los sin IMV (83,3% vs 25,9%, p La supervivencia global a 1, 3 y 5 anos fue del 66,7, del 33,3 y del 22,2%, respectivamente, en los pacientes con IMV, y del 90,7, del 72,4 y del 52,2% en el grupo sin IMV (p = 0,009). Conclusion La hepatectomia asociada a trombectomia parece estar justificada en un grupo seleccionado de pacientes con CHC e IMV, pudiendo aportar un beneficio de supervivencia con una aceptable tasa de morbilidad.

This review highlights recently reported strategies aimed at quantifying severity of illness earlier in the course of acute pancreatitis and at preventing secondary infection in pancreatic necrosis.New and improved scoring models appear to suggest that the optimal interventional window is between 24 and 72 h of the onset of severe acute pancreatitis. Prospective randomized clinical trials in which patients with severe acute pancreatitis were treated with broad-spectrum antimicrobial regimens as prophylaxis, however, have demonstrated no benefit in terms of preventing late infection in pancreatic necrosis. In contrast, early enteral nutrition with various formulas and supplements, including probiotics, may confer a clinical advantage in terms of morbidity and mortality.Continuing to advocate antimicrobial prophylaxis in severe acute pancreatitis is not reasonable, in view of the evidence now available from two large clinical trials. Current guidelines should be revised because of the potential harm to gastrointestinal ecology associated with long-term antibiotic treatment. A suitable alternative way to prevent bacterial overgrowth and secondary infection is lacking, however.

To assess the association between inappropriate antibiotic therapy and clinical outcomes for complicated community-acquired intra-abdominal infections in Spain, patient records from October 1998 to August 2002 in 24 hospitals were reviewed. Initial empiric therapy was classified appropriate if all isolates were sensitive to at least 1 of the antibiotics administered. Multivariate analyses were performed to assess associations between appropriateness of therapy and patient outcomes. Healthcare resource use was measured as hospital length of stay (LOS) and d on intravenous antibiotic therapy. A total of 425 patients were included. Of these, 387 (91%) received appropriate initial empiric therapy. Patients on inappropriate therapy were less likely to have clinical success (79% vs 26%, p

Complicated intraabdominal infections (i.e., those requiring both operative drainage and antimicrobial therapy) are among the most common infections in general surgery. Antimicrobial therapy is an important element in the management of these infections; there are convincing data that absent or inadequate empiric antibiotic therapy results in both increased failure rates and increased mortality. 1–4 The infecting flora seen with community-acquired intraabdominal infections is well known and consists of aerobic, facultative, and anaerobic gram-negative bacilli, various streptococci and enterococci, and a plethora of gram-positive anaerobes. 5–7 The synergistic interactions between endotoxin-bearing gram-negative organisms and Bacteroides fragilis define both groups as important targets for antimicrobial therapy. 8 Ertapenem (formerly MK-0826, Merck & Co., Inc.) is being investigated as a once-a-day parenteral β-lactam antimicrobial agent with the potential for use as monotherapy for the treatment of community-acquired mixed flora infections. This approach is based on its spectrum of activity, previously reported clinical studies that used once-a-day dosing, pharmacodynamic studies in animals, and pharmacokinetic studies in both humans and animals. 9,10 Ertapenem is highly active in vitro against gram-positive and gram-negative aerobic, facultative, and anaerobic bacteria, including the predominant pathogens responsible for intraabdominal infections. 11–13 However, it provides limited coverage against Pseudomonas aeruginosa, Acinetobacter spp, and enterococci, organisms generally associated with nosocomial infections. The primary objectives of this study were to determine the clinical and microbiologic efficacy and safety of ertapenem for patients with complicated intraabdominal infections. The comparative agent was piperacillin/tazobactam, a β-lactam/β-lactamase inhibitor combination agent that has been well studied and is approved in the treatment of intraabdominal infection. 14 This agent is typically administered at 3.375 g every 6 hours in the United States. This study also provided an opportunity to analyze an additional element of clinical trial design, the adequacy of surgical source control. Inadequate control of infection, through either incomplete drainage or incomplete management of enteric perforations, is an independent risk factor for treatment failure. 15,16 An expert panel review process was conducted to examine, under blinded conditions, the adequacy of surgical source control as a component of evaluability in a prospectively generated and well-documented group of patients.

Anaerobes are an important component of many serious, deep tissue infections, especially complicated intra-abdominal (IAI), complicated skin and skin structure (SSSI), and acute pelvic (PI) infections. This study compares the efficacy of ertapenem, 1 g once a day, in the treatment of adults with anaerobic IAI, SSSI, and PI to piperacillin-tazobactam, 3.375 g every 6 hours.Three randomized, double-blind trials comparing ertapenem to piperacillin-tazobactam for treatment of IAI, SSSI, and PI were conducted. This subgroup analysis included 623 patients, whose baseline culture grew one or more anaerobic pathogens, from these three studies.Anaerobes most commonly isolated were Bacteroides fragilis group (IAI) and peptostreptococci (SSSI and PI). The median duration of ertapenem and piperacillin-tazobactam therapy, respectively, in these subgroups was 6 and 7 days for IAI, 7 and 8 days for SSSI, and 4 and 5 days for PI. Cure rates for all evaluable patients with anaerobic infection were 89.3% (242/271) for ertapenem and 85.9% (220/256) for piperacillin-tazobactam (95% CI for the difference, adjusting for infection, -2.6% to 9.3%), indicating that the two treatments were equivalent. Cure rates by infection, for ertapenem and piperacillin-tazobactam, respectively, were as follows: IAI, 86.4% (133/154) and 82.4% (117/142); SSSI, 84.4% (27/32) and 82.4% (28/34); PI, 96.5% (82/85) and 93.8% (75/80). The frequency and severity of drug-related adverse experiences were comparable in both treatment groups.In this subgroup analysis, ertapenem was as effective as piperacillin-tazobactam for treatment of adults with moderate to severe anaerobic IAI, SSSI, and PI, was generally well tolerated, and had a similar safety profile.

Bacterial infections are frequent complications in patients with liver cirrhosis. Cirrhotic patients present abnormalities in both innate and adaptive immune responses, including a deficient neutrophil recruitment to infected sites. The purpose of this study was to assess neutrophil-endothelium interactions in cirrhotic patients and evaluate the effects of G-CSF on this process. We studied neutrophil adhesion and transendothelial migration in 14 cirrhotic patients and 14 healthy controls. We also analyzed neutrophil expression of the adhesion molecules CD62L and CD11b in whole blood by flow cytometry. Cirrhotic patients expressed higher levels of CD11b than healthy controls, whereas CD62L expression was significantly lower, suggesting exposure of neutrophils to activating agents within the bloodstream. Neutrophils from cirrhotic patients showed increased adhesion to both resting and tumor necrosis factor alpha-stimulated microvascular endothelial cells and decreased transendothelial migration. Granulocyte colony-stimulating factor (G-CSF) (100 ng/ml) significantly enhanced neutrophil adhesion to microvascular endothelial cells in healthy controls but not in cirrhotic patients. G-CSF also significantly improved neutrophil transmigration in cirrhotic patients and healthy controls. In conclusion, cirrhotic patients exhibit increased neutrophil adhesion to microvascular endothelium and deficient transendothelial migration. G-CSF enhances neutrophil transendothelial migration in cirrhotic patients despite having no effect on neutrophil adhesion. Therefore, G-CSF may be able to increase neutrophil recruitment into infected sites in these patients.

Background: Secondary peritonitis is an advanced form of complicated intra-abdominal infection (cIAI) requiring hospitalization, surgical source control, and empiric antibiotic therapy against causative aerobic and anaerobic bacteria. Methods: This pooled analysis of four prospective, active-controlled randomized clinical trials compared the efficacy and safety of moxifloxacin with that of comparator antibiotics in patients with confirmed secondary peritonitis. The primary efficacy endpoint was clinical success rate at test-of-cure (TOC) between day 10 and 45 post-therapy in the per-protocol (PP) population. Safety and clinical efficacy were assessed also in the intent-to-treat population (ITT). Bacteriological success was assessed at TOC in the microbiologically-valid population as a secondary efficacy endpoint. Results: Overall clinical success rates at TOC were 85.3% (431 of 505 patients) in the moxifloxacin and 88.4% (459 of 519 patients) in the comparator treatment groups (PP population, point estimate for the difference in success rates: -3.0%; 95% CI -7.06%, 1.05%), respectively. Similar clinical success rates between moxifloxacin and comparators were observed by anatomical site of infection, and ranged from 80.6% to 100% for moxifloxacin and from 71.4% to 96.6% for comparators, respectively. Bacteriologic success rates were similar with moxifloxacin (82.4%) and comparators (86.8%), respectively. The proportion of patients experiencing any treatment-emergent adverse events was slightly higher with moxifloxacin (67.3%) versus comparators (59.8%). Rates of drug-related adverse events (20.9% versus 20.0%) and deaths (4.3% versus 3.4%) were similar in moxifloxacin and comparator groups; none of the deaths were drug-related. Conclusions: The data suggests that once-daily IV (or IV/PO) moxifloxacin has a comparable efficacy and safety profile to antibiotic regimens approved previously in the subgroup of patients with secondary peritonitis of mild-to-moderate severity.

Accurate detection of liver lesions is of great importance in hepatic surgery planning. Recent studies have shown that the detection rate of liver lesions is significantly higher in gadoxetic acid-enhanced magnetic resonance imaging (Gd–EOB–DTPA-enhanced MRI) than in contrast-enhanced portal-phase computed tomography (CT); however, the latter remains essential because of its high specificity, good performance in estimating liver volumes and better vessel visibility. To characterize liver lesions using both the above image modalities, we propose a multimodal nonrigid registration framework using organ-focused mutual information (OF-MI). This proposal tries to improve mutual information (MI) based registration by adding spatial information, benefiting from the availability of expert liver segmentation in clinical protocols. The incorporation of an additional information channel containing liver segmentation information was studied. A dataset of real clinical images and simulated images was used in the validation process. A Gd–EOB–DTPA-enhanced MRI simulation framework is presented. To evaluate results, warping index errors were calculated for the simulated data, and landmark-based and surface-based errors were calculated for the real data. An improvement of the registration accuracy for OF-MI as compared with MI was found for both simulated and real datasets. Statistical significance of the difference was tested and confirmed in the simulated dataset (p < 0.01).

Antibiotic therapy for complicated intra-abdominal infections (cIAIs) should provide broad-spectrum coverage both Gram-positive and Gram-negative microorganisms. The PROMISE study compared the clinical and bacteriological efficacy and safety of moxifloxacin versus ertapenem for the treatment of cIAIs. This randomised, prospective, double-dummy, double-blind, multicentre trial was designed as a non-inferiority study. The safety and efficacy of 5–14 days of daily intravenous moxifloxacin (400mg) or ertapenem (1g) were compared in patients with cIAIs requiring surgery and parenteral antibiotic therapy. The primary and secondary endpoints included clinical and bacteriological responses at 21–28 days after the end of treatment (TOC), respectively. Of 830 enrolled patients, 699 were efficacy valid. Moxifloxacin was non-inferior to ertapenem regarding clinical success [89.5% (315/352) versus 93.4% (324/347); 95% confidence interval (CI) −7.9%, 0.4%]. There were no significant differences between groups for any of the primary causes or types of cIAI regarding clinical response. Bacteriological success was achieved in 86.5% (257/297) of moxifloxacin-treated patients and 90.2% (249/276) of ertapenem-treated patients (95% CI −9.0%, 1.5%). There were no major differences between groups regarding the frequency or types of organisms eradicated. The incidence of adverse events (AEs) was higher with moxifloxacin than ertapenem (P=0.039), however a similar number of drug-related AEs was seen in each group (P=1.000). Wound infections, nausea and increased lipase were the most commonly reported AEs with both agents. The results show that moxifloxacin is a valuable treatment option for a range of community-acquired cIAIs with mild-to-moderate severity [Clinical Trials.gov Identifier: NCT00492726].

Laura Fernandez-de-Manuel1,5, Maria J. Ledesma-Carbayo1,5, Daniel Jimenez-Carretero1,5, Javier Pascau2, Jose L. Rubio-Guivernau1,5, Jose M. Tellado3, Enrique Ramon4, Manuel Desco2 and Andres Santos1,5 1Biomedical Image Technologies Lab, Universidad Politecnica de Madrid 2Medicina y Cirugia Experimental, Hospital General Universitario Gregorio Maranon 3 Servicio de Cirugia General I, Hospital General Universitario Gregorio Maranon 4 Servicio de Radiodiagnostico, Hospital General Universitario Gregorio Maranon, Madrid 5Biomedical Research Center in Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN), Madrid Spain

In this work we propose an active surface method to segment complete liver volumes from preoperative CT abdominal images. The method finds the surface that minimizes an energy function combining intensity inside and outside the surface, gradient information and curvature restrictions. The implementation is based on a level set technique following a multi-resolution strategy to reduce computing time. It requires only a single seed point inside the liver to initialize the active surface. The algorithm has been validated on a set of previously diagnosed livers. Resulting segmentations have been supervised by clinicians and radiologists, and numerically evaluated in terms of volume measurements with respect to those obtained from radiologists' manual segmentations. Additionally, radiologists analyzed the necessity of additional corrections on segmenting volumes.

Skin test anergy, the failure to produce a delayed type hypersensitivity (DTH) response, is associated with an increase in infection-related complications and death usually due to multiple organ failure (MOF). Refractory intravascular activation of polymorphonuclear neutrophils (PMNs) has been implicated in the development of MOF. We studied 20 critically ill surgical patients with life threatening infections to determine if PMN intravascular activation was present and how this affected essential PMN functions such as exudation. The 11 anergic patients had a more intense inflammatory response to their infection. Plasma lactoferrin was 6.1 ± 0.3 μg/ml in anergic patients compared to 3.9 ± 1.5 in reactives P < 0.05, accompanied by reduced total primary (3.3 ± 1.9 vs 4.7 ± 2.1 μg/106 PMN P < 0.01) and secondary (2.8 ± 0.4 vs 5.0 ± 0.9 μg/106 PMN P < 0.01) granule content, respectively. In vitro superoxide production following 100 ng/ml PMA stimulation was 0.44 ± 0.1 in anergics vs 0.36 ± 0.1 nmol/μg PMN protein in reactivities, P < 0.05. PMN chemotaxis was 8.2 ± 0.6 PMNs/HPF in anergics compared to 10.2 ± 1.6 PMNs/HPF in reactives P < 0.05, accompanied by decreased PMN delivery to skin blister windows (3.2 ± 1.4 vs 4.5 ± 1.9 × 107 PMN/ml, respectively, P < 0.05). We conclude that critically ill anergic surgical patients have increased intravascular PMN activation, which may contribute to oxygen-derived tissue damage in the vascular space, as well as a deficient delivery of effector cells in areas of bacterial invasion. This may lead to inability to clear the inflammatory signals which set up the vicious circle of MOF leading to death.

Background & Aims: In patients with severe, necrotizing pancreatitis, it is common to administer early, broad-spectrum antibiotics, often a carbapenem, in the hope of reducing the incidence of pancreatic and peripancreatic infections, although the benefits of doing so have not been proved. Methods: A multicenter, prospective, double-blind, placebo-controlled randomized study set in 32 centers within North America and Europe. Participants: One hundred patients with clinically severe, confirmed necrotizing pancreatitis: 50 received meropenem and 50 received placebo. Interventions: Meropenem (1 g intravenously every 8 hours) or placebo within 5 days of the onset of symptoms for 7 to 21 days. Main Outcome Measures: Primary endpoint: development of pancreatic or peripancreatic infection within 42 days following randomization. Other endpoints: time between onset of pancreatitis and the development of pancreatic or peripancreatic infection; all-cause mortality; requirement for surgical intervention; development of nonpancreatic infections within 42 days following randomization. Results: Pancreatic or peripancreatic infections developed in 18% (9 of 50) of patients in the meropenem group compared with 12% (6 of 50) in the placebo group (P = 0.401). Overall mortality rate was 20% (10 of 50) in the meropenem group and 18% (9 of 50) in the placebo group (P = 0.799). Surgical intervention was required in 26% (13 of 50) and 20% (10 of 50) of the meropenem and placebo groups, respectively (P = 0.476). Conclusions: This study demonstrated no statistically significant difference between the treatment groups for pancreatic or peripancreatic infection, mortality, or requirement for surgical intervention, and did not support early prophylactic antimicrobial use in patients with severe acute necrotizing pancreatitis

Serious nosocomial intra-abdominal infections are associated with high morbidity and mortality and represent a substantial drain on healthcare resources. Effective management of this type of infection requires the early use of appropriate, broad-spectrum empiric antimicrobial therapy. The consequences of delayed or inappropriate antimicrobial treatment can be severe-leading to an increased risk of death, re-operation, or prolonged hospitalization. Therefore, it is necessary to begin treatment as soon as possible with the most appropriate regimen, in terms of spectrum, timing, and duration.Review of pertinent English-language literature.Serious nosocomial intra-abdominal infections require broad-spectrum coverage because of the wide range of possible pathogens, which include difficult-to-treat organisms such as Pseudomonas aeruginosa and Bacteroides spp., and resistant strains of Klebsiella spp., Escherichia coli, and methicillin-resistant Staphylococcus aureus acquired from the hospital flora. The early use of appropriate, broad-spectrum empiric antimicrobial therapy for treating high-risk patients with intra-abdominal infections is considered, and appropriate use of the carbapenems, meropenem, and imipenem/cilastatin, is described.The carbapenems meropenem and imipenem/cilastatin have a spectrum of antimicrobial activity that covers the majority of expected pathogens, including anaerobes, as well as difficult-to-treat and resistant gram-negative strains. Early and appropriate use can reduce mortality and morbidity. Data from published clinical trials support the clinical effectiveness of these two carbapenems in intra-abdominal infections.

Objective: This study investigated whether treatment with the anti-tumor necrosis factor-or monoclonal antibody afelimomab would improve survival in septic patients with serum interleukin (IL)-6 concentrations of >1000 pg/ml, Design: Multicenter, double-blind, randomized, placebo-controlled study. Setting: Eighty-four intensive care units in academic medical centers in Europe and Israel. Patients: A total of 944 septic patients were screened and stratified by the results of a rapid qualitative immunostrip test for serum IL-6 concentrations. Patients with a positive test kit result indicating IL-6 concentrations of >1000 pg/mL were randomized to receive either afelimomab (n = 224) or placebo (n = 222), Patients with a negative IL-6 test (n = 498) were not randomized and were followed up for 28 days. Interventions: Treatment consisted of 15-min infusions of 1 mg/kg afelimomab or matching placebo every 8 hrs for 3 days. Standard surgical and intensive care therapy was otherwise delivered. Measurements and Main Results:The study was terminated prematurely after an interim analysis estimated that the primary efficacy end points would not be met. The 28-day mortality rate in the nonrandomized patients (39.6%, 197 of 498) was significantly lower (p

The peritoneal cavity contains resident and migratory cell populations, which play crucial roles in the local defensive response against bacterial invasion. Although mononuclear phagocytes predominate in the peritoneal cavity of healthy subjects, recent attention has been focused on mesothelial and dendritic cells. Kinetic analysis of inflammatory mediators has derived from experimental models of peritonitis, but advances in the understanding of the roles of molecules such as lipocortins, PAF, leukotriene B4, PPAR gamma agonists, and chemokines has also been made. Little is known about the peritoneal response to physical trauma in the context of the abdominal compartment syndrome. Studies on the cellular and molecular pathology of intra-abdominal abscesses, peritoneal sclerosis, and other less frequent clinical entities (e.g., tertiary peritonitis) are needed. Biological therapy may contribute to improved clinical management of such diseases.

Bacterial infections are frequent, life-threatening complications in cirrhotic patients. This study investigated in vivo neutrophil migration and phagocytic activity in cirrhotic patients with advanced liver disease, in liver transplant recipients, and in healthy volunteers, by use of the skin window technique. Complement receptor type III (CR3) expression was also measured in blood and elicited neutrophils. Neutrophil migration to skin windows and neutrophil in vivo phagocytosis of heat-killed Escherichia coli were significantly decreased in cirrhotic patients compared with healthy controls. Neutrophil migration and phagocytosis were decreased in cirrhotic patients with previous episodes of bacterial infection compared with noninfected patients. Expression of CR3 in circulating neutrophils was significantly higher in cirrhotic patients, whereas it was significantly reduced in elicited neutrophils of cirrhotic patients with previous bacterial infection. These data suggest that deficient neutrophil recruitment to the infection site and impaired phagocytic activity may contribute to bacterial infections in cirrhotic patients with advanced liver disease.

Background Catheter hub contamination is being increasingly recognized as a source of catheter-related sepsis. The authors have investigated the efficacy of a new hub design in preventing endoluminal catheter contamination and catheter-related sepsis arising at the hub. Methods Adult surgical and intensive care patients requiring a subclavian catheter for at least 1 week were randomly assigned to receive catheters with standard connectors (control group, n = 73) or equipped with a new hub model (new hub group, n = 78). Skin, catheter tip, and hub cultures were performed at the time the catheter was withdrawn because therapy was terminated or because of suspicion of sepsis, in which case peripheral blood cultures were taken. Results Of the 151 patients included, 15 (10%) developed catheter-related sepsis. Catheters were more often withdrawn because suspicion of infection in the control group (42 vs. 19%, p < 0.005). Catheter sepsis rate was higher in the control group (16 vs. 4%, p < 0.01) because of the low rate of catheter sepsis arising at the hub observed in the new hub group (1 vs. 11%, p < 0.01). The prevalence of culture-positive catheter hubs without associated bacteremia (colonization) was higher in the control group (18 vs. 5%, p < 0.03). Conclusions A new catheter hub has proved to be useful in preventing endoluminal bacterial colonization and catheter-related sepsis in subclavian lines inserted for a mean of 2 weeks.

OBJECTIVE To determine the mechanism for the reduced polymorphonuclear leukocyte exudation in critically ill anergic patients. DESIGN Prospective consecutive patient study. SETTING Tertiary care surgical intensive care unit. PATIENTS Eighteen patients with intra-abdominal injections were studied. INTERVENTIONS Critically ill patients were stratified based on their delayed type hypersensitivity response to ubiquitous antigens. Polymorphonuclear leukocytes were isolated from blood and from exudate blister type skin windows. Adhesion and chemotactic surface receptors were measured, as was cytokine content and chemoattraction capacity of skin window fluid for control neutrophils. MEASUREMENTS AND MAIN RESULTS Circulating neutrophils from anergic patients have increased CR3 adherence receptors compared with those neutrophils from reactive patients. f-met-leu-phe receptors are equal in number and C5a receptors are either significantly reduced in number or occupied with ligand. This same receptor pattern is maintained after neutrophil exudation in both patient groups. Serum and skin window fluid from anergic patients attracted less neutrophils in vitro and in vivo. CONCLUSIONS These data suggest two possible mechanisms for the reduced neutrophil delivery of critically ill anergic patients: a receptor-mediated increased adherence to vascular endothelium preventing diapedesis; reduced chemo-attraction potential of serum, and possibly, exudate fluid.

Objectives: To examine the oxidative capacity of circulating and exudate polymorphonuclear neutrophils from reactive patients and anergic patients before surgery to determine why anergic patients have increased sepsis-related mortality once an infectious complication develops. Design: Prospective in vitro patient study. Setting: Tertiary care, major university teaching hospital. Participants: Surgical patients admitted for major elective gastrointestinal surgery. Main Outcome and Measures: We used flow cytometry and the dye 2-7-dichlorofluorescein diacetate to measure hydrogen peroxide production of circulating and exudate polymorphonuclear neutrophils at baseline and after stimulation with Staphylococcus epidermidis. Results: We found that polymorphonuclear neutrophils were primed in the intravascular space as evidenced by increased numbers of formyl-methionyl-leucyl-phenylalanine receptors, increased hydrogen peroxide production at baseline, and increased hydrogen peroxide production with stimulation. These results were more evident in the anergic patient. After exudation, anergic polymorphonuclear neutrophils lost most of their capacity to produce additional hydrogen peroxide. Conclusions: The data suggest that this intravascular priming adversely affected polymorphonuclear neutrophils during exudation, more marked in the anergic patient, and may contribute to the sepsis-related mortality of the anergic patients. (Arch Surg. 1993;128:691-695)

The neutrophil has been implicated as a source of oxygen free radicals provoking the reperfusion injury in various ischemic organs. This provided the motivation to explore the pathophysiologic role of the neutrophil in a swine model of postischemic latissimus dorsi myocutaneous flaps. Neutrophil function, neutrophil sequestration, and the anatomic distribution of muscle injury were estimated following a 6- to 8-hour global ischemic insult. Neutrophil function as measured by phorbol myristate acetate-stimulated superoxide production was found to be enhanced on reperfusion of ischemic flaps (n = 17). Neutrophil sequestration estimated from the arterial-venous difference of flap blood (n = 12) demonstrated that postischemic flaps more avidly sequester neutrophils than nonischemic flaps. The anatomic distribution of muscle injury (n = 7) was predominantly localized to the proximal portion of the ischemic flap. The enhanced functional response exhibited by neutrophils reperfusing an ischemic myocutaneous flap supports an active neutrophil role in the mediation of reperfusion injury.

• Albeit anergy in patients before surgery is associated with an increase in septic-related complications and mortality, it is not clear whether this is due to a downregulated nonspecific host defense or a specific cellular immune defect. We studied polymorphonuclear leukocyte neutrophil (PMN) function in 14 patients who were admitted for elective surgery and compared them with 5 healthy controls. At admission, patients were classified according to their delayed-type hypersensitivity skin test response into reactive or anergic groups. In vivo PMN delivery to skin windows, the plasma lactoferrin level, serum and skin window fluid chemoattractant activity, and in vitro superoxide production were measured. Compared with reactive patients, anergic patients showed an increased cell delivery (8.7× 10 6 PMNs per well vs 1.6× 10 6 PMNs per well), an increased plasma lactoferrin level (4.4± 1.5 mg/L vs 3.1 ± 0.8 mg/L), an increased chemoattractant capacity of serum and skin window fluid (38 ± 21 cells per high-power field vs 16.8±7.2 cells per high-power field), and an increased superoxide production. We concluded that nonspecific host defense, as reflected by PMNs, is enhanced in anergic patients before surgery and may not explain the increased susceptibility to infection. ( Arch Surg. 1990;125:49-53)

The role of the Nae/Ke ratio (the ratio of exchangeable sodium to exchangeable potassium) was examined as a nutritional marker in surgical patients in relation to anthropometrical and biochemical indexes by its ability to identify patients at risk for mortality after hospitalization. In 73 patients with sepsis and malnutrition (Training Group, Madrid) the following were determined: percentage of recent weight loss, triceps skin fold, midarm muscle circumference, serum albumin, serum transferrin, delayed hypersensitivity skin test response, total lymphocytes, and Nae/Ke ratio by multiple isotope dilution. The predictive power of Nae/Ke ratio was so strong (F = 105.1; p less than 0.00001) that it displaced anthropometric, biochemical, and immunologic variables from the linear equation derived from stepwise discriminant analysis using hospital mortality as the dependent variable. A theoretical curve of expected deaths was developed, based on an equation obtained by logistic regression analysis: Pr/death/ = 1/(1 + e[11.8-5.2 Nae/Ke]). Pre- and post-test probabilities on that curve allowed us to determine two cut-off values, Nae/Ke ratios of 1.5 and 2.5, which were markers for nonrisk and mortality, respectively. The model was tested in a heterogeneous data base of surgical patients (n = 417) in another hospital (Validation Group, Montreal). For patients exhibiting an abnormal Nae/Ke ratio (greater than 1.2) and a greater than 10% of probability of death, 54 deaths were expected and 53 observed (X2 = 1.8 NS). Two tests confirmed the basic agreement between the model and its performance, a G statistic of -0.704 and the area beneath the "receiver-operating-characteristic" (ROC) curve (Az = 0.904 + 0.0516 for the Madrid group vs. Az = 0.915 + 0.0349 for the Montreal group, NS). It was concluded from this analysis that, compared with the usual anthropometric measurements, the Nae/Ke ratio, if available, is the best method for identifying malnourished patients at risk of dying.

Proceedings of: 2011 33rd Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). Boston, MA, USA, 30 August - 03 September 2011. Advanced liver surgery requires a precise pre-operative planning, where liver segmentation and remnant liver volume are key elements to avoid post-operative liver failure. In that context, level-set algorithms have achieved better results than others, especially with altered liver parenchyma or in cases with previous surgery. In order to improve functional liver parenchyma volume measurements, in this work we propose two strategies to enhance previous level-set algorithms: an optimal multi-resolution strategy with fine details correction and adaptive curvature, as well as an additional semiautomatic step imposing local curvature constraints. Results show more accurate segmentations, especially in elongated structures, detecting internal lesions and avoiding leakages to close structures. This study was partially supported by research projects PI09/91058, PI09/91065,ENTEPRASE PS-300000-2009-5, AMIT-CDTI, TEC2010-21619-C04 and PRECISION IPT-300000- 2010-3, from Spain’s Ministry of Science & Innovation, the project ARTEMIS Comunidad de Madrid, and with assistance from the European Regional Development Fund (FEDER). Publicado