Therapeutic thoracic duct drainage: A systematic review of the Eastern European experience and future potential.

Thoracic duct drainage (TDD) is gaining renewed interest, largely due to accumulation of evidence supporting the gut-lymph model, where toxic mesenteric lymph from the intestine contributes to development of multi-organ failure in acute and critical illness (ACI). Advances in minimally invasive TDD have added to this growing interest. The English TDD literature has been previously reviewed, but the more extensive Eastern European literature has not been available to English readers. Therefore, we undertook a systematic search of Eastern European human TDD studies using Scopus and PubMed databases and Russian language websites. Indications for TDD, clinical outcomes, and complications were reviewed. 113 studies, published between 1965 and 2015, were reviewed. The most common indications for TDD were hepatic failure, acute pancreatitis, and peritonitis. It was often used late and when other treatment options had been exhausted. Human TDD appeared safe and probably effective, especially when combined with lymphosorption. The benefit appeared to correlate with the volume of lymph drained. A randomized controlled trial (and some case-control studies) showed reduced mortality in patients with ACI with TDD. Other benefits included rapid normalization of blood parameters and decreased organ edema. This review provides further support for the gut-lymph model and justification for high quality randomized controlled trials of TDD in ACI. It also highlights other potential indications for TDD, such as bridging patients with liver failure to surgery or transplant.

Fluorescent Tracers for In Vivo Imaging of Lymphatic Targets.

The lymphatic system continues to gain importance in a range of conditions, and therefore, imaging of lymphatic vessels is becoming more widespread for research, diagnosis, and treatment. Fluorescent lymphatic imaging offers advantages over other methods in that it is affordable, has higher resolution, and does not require radiation exposure. However, because the lymphatic system is a one-way drainage system, the successful delivery of fluorescent tracers to lymphatic vessels represents a unique challenge. Each fluorescent tracer used for lymphatic imaging has distinct characteristics, including size, shape, charge, weight, conjugates, excitation/emission wavelength, stability, and quantum yield. These characteristics in combination with the properties of the target tissue affect the uptake of the dye into lymphatic vessels and the fluorescence quality. Here, we review the characteristics of visible wavelength and near-infrared fluorescent tracers used for in vivo lymphatic imaging and describe the various techniques used to specifically target them to lymphatic vessels for high-quality lymphatic imaging in both clinical and pre-clinical applications. We also discuss potential areas of future research to improve the lymphatic fluorescent tracer design.

Pain patterns in chronic pancreatitis and chronic primary pain.

BACKGROUND: Abdominal pain is the most distressing symptom of chronic pancreatitis (CP), and current treatments show limited benefit. Pain phenotypes may be more useful than diagnostic categories when planning treatments, and the presence or absence of constant pain in CP may be a useful prognostic indicator. AIMS: This cross-sectional study examined dimensions of pain in CP, compared pain in CP with chronic primary pain (CPP), and assessed whether constant pain in CP is associated with poorer outcomes. METHODS: Patients with CP (N = 91) and CPP (N = 127) completed the Comprehensive Pancreatitis Assessment Tool. Differences in clinical characteristics and pain dimensions were assessed between a) CP and CPP and b) CP patients with constant versus intermittent pain. Latent class regression analysis was performed (N = 192) to group participants based on pain dimensions and clinical characteristics. RESULTS: Compared to CPP, CP patients had higher quality of life (p < 0.001), lower pain severity (p < 0.001), and were more likely to use strong opioids (p < 0.001). Within CP, constant pain was associated with a stronger response to pain triggers (p < 0.05), greater pain spread (p < 0.01), greater pain severity, more features of central sensitization, greater pain catastrophising, and lower quality of life compared to intermittent pain (all p values ≤ 0.001). Latent class regression analysis identified three groups, that mapped onto the following patient groups 1) combined CPP and CP-constant, 2) majority CPP, and 3) majority CP-intermittent. CONCLUSIONS: Within CP, constant pain may represent a pain phenotype that corresponds with poorer outcomes. CP patients with constant pain show similarities to some patients with CPP, potentially indicating shared mechanisms.

Network meta-analysis comparing techniques and outcomes of stump closure after distal pancreatectomy.

BACKGROUND: The incidence of postoperative pancreatic fistula (POPF) after distal pancreatectomy remains high, and different pancreatic stump closure techniques have been used to reduce the incidence. A network meta-analysis was undertaken to compare the most frequently performed pancreatic stump closure techniques after distal pancreatectomy and determine the technique associated with the lowest POPF rate. METHODS: A systematic search of the Scopus, PubMed, MEDLINE and Embase databases was conducted to identify eligible RCTs. The primary outcome was the occurrence of clinically relevant POPF. Secondary outcomes were duration of operation, blood loss, intrabdominal collections, postoperative complications and 30-day mortality. RESULTS: Sixteen RCTs including 1984 patients and eight different pancreatic stump closure techniques were included in the network meta-analysis. Patch coverage of the pancreatic stump (round ligament or seromuscular patch) after stapler or suture closure ranked best, with the lowest rates of clinically relevant POPF, lowest volume of intraoperative blood loss, fewer intra-abdominal abscesses, and lower rates of overall complications and 30-day mortality. Round ligament patch closure outperformed seromuscular patch closure in preventing clinically relevant POPF with a significantly larger cohort for comparative analysis. Pancreaticoenteric anastomotic closure consistently ranked poorly for most reported postoperative outcomes. CONCLUSION: Patch coverage after stapler or suture closure has the lowest POPF rate and best outcomes among stump closure techniques after distal pancreatectomy.

ANTECEDENTES: La incidencia de fístula pancreática (postoperative pancreatic fistula, POPF) tras una pancreatectomía distal sigue siendo alta y se han utilizado diferentes técnicas para el cierre del muñón pancreático con la intención de reducir su incidencia. Se realizó un metaanálisis en red para comparar las técnicas de cierre del muñón pancreático realizadas con más frecuencia después de la pancreatectomía distal y determinar qué técnica se asocia a una menor tasa de POPF. MÉTODOS: Se realizó una búsqueda sistemática en las bases de datos Scopus, PubMed, Medline y EMBASE de los RCTs que podían ser incluidos en estudio. La variable principal fue la aparición de POPF clínicamente relevante. Las variables secundarias fueron el tiempo operatorio, la pérdida de sangre, las colecciones intraabdominales, las complicaciones postoperatorias y la mortalidad a los 30 días. RESULTADOS: En el metaanálisis se incluyeron 16 RCTs con 1.984 pacientes y 8 técnicas diferentes de cierre del muñón pancreático. Los mejores resultados (menor tasa de POPF clínicamente relevante, menor pérdida sanguínea intraoperatoria, menor número de abscesos intraabdominales, menor tasa de complicaciones generales y menor mortalidad a los 30 días) se obtuvieron con el refuerzo del muñón pancreático con parches (de ligamento redondo o seromuscular), seguidos del grapado quirúrgico o la sutura simple. El cierre con parche del ligamento redondo fue superior al parche seromuscular en la prevención de POPF clínicamente relevante en una cohorte suficiente para el análisis estadístico comparativo. Los peores resultados en la mayoría de las variables postoperatorias se obtuvieron con el cierre simple. CONCLUSIÓN: En la pancreatectomía distal, la menor tasa de POPF y los mejores resultados perioperatorios se obtuvieron con el refuerzo con parches, seguidos del grapado quirúrgico o la sutura simple.

Patient-Reported Barriers to Accessing Surgical Care in Northern Vanuatu.

BACKGROUND: The Lancet Commission on Global Surgery proposed that population access to essential surgical care within 2 h is a core indicator of health system preparedness. Little evidence exists to characterise access to surgical care for island nations, including Vanuatu, a lower middle-income country in the Western Pacific. METHODS: A descriptive, facility-based, survey of surgical inpatients was undertaken over a 6-month period at Northern Provincial Hospital (NPH), Espiritu Santo, Vanuatu. This evaluated demographics, access to surgical care using the 'three delays' framework and clinical outcomes. RESULTS: A total of 121 participants were surveyed (60% of all surgical admissions), of which 31% required emergency surgery. Only 20% of emergency surgical cases accessed care within 2 h. There were no emergency cases from Torba or Malekula. The first delay (delay in seeking care) had the biggest impact on timely access. There was a geographic gradient to access, gender preponderance (males), and a delay in seeking surgical care due to a preference for traditional healers. CONCLUSION: There is urgent need to improve access to surgical care in Vanuatu, particularly for Torba and Malekula catchments. Demographic, geographic, sociocultural, and economic factors impact on timely access to surgical care within the northern regions of Vanuatu and support the notion that addressing access barriers is more complex than ensuring the availability of surgical resources. Future priorities should include efforts to reduce the first delay, address the role of traditional medicine, and review the geographic disparities in access.

Meta-analysis of an artery-first approach versus standard pancreatoduodenectomy on perioperative outcomes and survival.

BACKGROUND: The aim of this systematic review and meta-analysis was to evaluate perioperative outcomes and survival in patients undergoing an artery-first approach to pancreatoduodenectomy in comparison with those having standard pancreatoduodenectomy. METHODS: A systematic search of PubMed, MEDLINE, Embase and the Cochrane Database of Systematic Reviews was performed in accordance with PRISMA guidelines. Comparative studies including patients who underwent artery-first pancreatoduodenectomy and standard pancreatoduodenectomy were analysed. RESULTS: Seventeen studies were included in the final analysis. There were 16 retrospective cohort or case-control studies and one RCT. A total of 1472 patients were included in the meta-analysis, of whom 771 underwent artery-first pancreatoduodenectomy and 701 had standard pancreatoduodenectomy. Intraoperative blood loss (mean difference -389 ml; P < 0·001) and the proportion of patients requiring intraoperative transfusion (10·6 per cent (54 of 508) versus 40·1 per cent (186 of 464); P < 0·001) were significantly lower in the artery-first group. Although rates of perioperative mortality were comparable between the two groups, perioperative morbidity (35·5 per cent (263 of 741) versus 44·3 per cent (277 of 625); P = 0·002), and the incidence of grade B/C pancreatic fistula (7·4 per cent (26 of 353) versus 12·8 per cent (42 of 327); P = 0·031) were significantly lower in the artery-first group. The R0 resection rate (75·8 per cent (269 of 355) versus 67·0 per cent (280 of 418); P < 0·001) and overall survival (hazard ratio 0·72, 95 per cent c.i. 0·60 to 0·87; P < 0·001) were significantly higher in the artery-first group. CONCLUSION: The artery-first approach to pancreatoduodenectomy may be associated with improved perioperative outcomes and survival.

A comprehensive pain assessment tool (COMPAT) for chronic pancreatitis: Development, face validation and pilot evaluation.

BACKGROUND/OBJECTIVES: Chronic pancreatitis (CP) pain is challenging to treat. Treatment selection is hampered by there being no validated pain assessment tool that accounts for the complexity of CP pain and its underlying mechanisms. This study aims to develop a comprehensive pain assessment tool (COMPAT) specific for CP, evaluate its face validity with experts and patients and test it with a pilot cohort of patients. METHODS: COMPAT was developed from existing pain assessment tools and a literature review. Face validity was conducted by pancreatologists and CP patients using an item-content validity index for importance, relevance and clarity. Subsequent revisions were made to COMPAT. A pilot cohort of CP patients tested COMPAT. RESULTS: COMPAT was developed and covered all important aspects of CP pain. Experts and CP patients reported that 70% of questions were important and relevant to CP pain. Most experts were willing to use COMPAT in clinic, ward/hospital and research settings. The most common location of pain was the epigastrium and food was the most important trigger. Pain Pattern C (constant background pain with pain attacks), had significantly higher frequency of pain attacks, higher opioid use, and affective descriptors of pain than Pattern A (pain attacks with no background pain). CONCLUSIONS: COMPAT has high face validity and met with high acceptance. CP patients successfully self-reported their pain with COMPAT. The results reveal many differences in the CP pain within the pilot cohort, which may reflect different mechanisms of pain. A larger prospective cohort study is planned to further validate COMPAT.

High-resolution electrical mapping of porcine gastric slow-wave propagation from the mucosal surface.

BACKGROUND: Gastric motility is coordinated by bioelectrical slow waves, and gastric dysrhythmias are reported in motility disorders. High-resolution (HR) mapping has advanced the accurate assessment of gastric dysrhythmias, offering promise as a diagnostic technique. However, HR mapping has been restricted to invasive surgical serosal access. This study investigates the feasibility of HR mapping from the gastric mucosal surface. METHODS: Experiments were conducted in vivo in 14 weaner pigs. Reference serosal recordings were performed with flexible-printed-circuit (FPC) arrays (128-192 electrodes). Mucosal recordings were performed by two methods: (i) FPC array aligned directly opposite the serosal array, and (ii) cardiac mapping catheter modified for gastric mucosal recordings. Slow-wave propagation and morphology characteristics were quantified and compared between simultaneous serosal and mucosal recordings. KEY RESULTS: Slow-wave activity was consistently recorded from the mucosal surface from both electrode arrays. Mucosally recorded slow-wave propagation was consistent with reference serosal activation pattern, frequency (P≥.3), and velocity (P≥.4). However, mucosally recorded slow-wave morphology exhibited reduced amplitude (65-72% reduced, P<.001) and wider downstroke width (18-31% wider, P≤.02), compared to serosal data. Dysrhythmias were successfully mapped and classified from the mucosal surface, accorded with serosal data, and were consistent with known dysrhythmic mechanisms in the porcine model. CONCLUSIONS & INFERENCES: High-resolution gastric electrical mapping was achieved from the mucosal surface, and demonstrated consistent propagation characteristics with serosal data. However, mucosal signal morphology was attenuated, demonstrating necessity for optimized electrode designs and analytical algorithms. This study demonstrates feasibility of endoscopic HR mapping, providing a foundation for advancement of minimally invasive spatiotemporal gastric mapping as a clinical and scientific tool.

Pain assessment in chronic pancreatitis: A comparative review of methods.

BACKGROUND: Patients with chronic pancreatitis (CP) frequently report chronic abdominal pain that adversely impacts their quality of life. Assessment of pain in CP is required for clinical management and clinical studies. International consensus guidelines recognized a lack of specific and validated pain assessment tools for CP. Therefore, the aim of this systematic review is to identify and compare all clinical studies that assessed pain in the context of a treatment for pain in CP. METHODS: A systematic literature search was performed in PubMed, Cochrane Library and Ovid MEDLINE. The search identified all intervention studies for pain in CP and the pain assessment tools used based on pre-defined inclusion and exclusion criteria. RESULTS: Of 341 articles identified, 137 studies were included. Pain assessment tools were both general and CP-specific. The latter were used in only 22 (16%) studies. Despite recommendations the aspects of pain assessed were limited and variable between tools. Validation of these tools in CP patients was limited to quality of life measures. None of the pain assessment tools evaluated duration of pain and postprandial pain. CONCLUSIONS: There are no published pain assessment tools for CP that includes all relevant aspects of pain. There is the need to develop a comprehensive and validated pain assessment tool for patients with CP to standardised pain assessment, identify likely underlying pain mechanisms, help select appropriate treatments, report outcomes from interventions, improve clinical communication and aid the allocation of patients to clinical trials.

Challenges and Opportunities in the Provision of Surgical Care in Vanuatu: A Mixed Methods Analysis.

BACKGROUND: The Pacific island nation of Vanuatu faces a number of challenges in delivering surgical care to its population. We aimed to understand and document the barriers, opportunities and required actions to improve surgical care in the country using a mixed methods analysis which incorporated the perspectives of local health stakeholders. METHODS: A baseline quantitative assessment of surgical capacity in Vanuatu was carried out using the WHO situational analysis tool. Twenty semi-structured interviews were then conducted on the two main islands (Efate and Espiritu Santo) with surgeons, allied health staff, health managers, policy-makers and other key stakeholders, using a grounded theory qualitative case study methodology. Initial informants were identified by purposive sampling followed by snowball sampling until theoretical saturation was reached. Interviews were open and axially coded with subsequent thematic analysis. RESULTS: Vanuatu faces deficits in surgical infrastructure, equipment and human resources, especially in the rural provinces. Geographic isolation, poverty and culture-including the use of traditional medicine and low health literacy-all act as barriers to patients accessing timely surgical care. Issues with governance, human resourcing and perioperative care were commonly identified by stakeholders as key challenges facing surgical services. Increasing outreach clinics, developing efficient referral systems, building provincial surgical capacity and undertaking locally led research were identified as key actions that can improve surgical care. CONCLUSION: Documenting locally identified challenges and opportunities for surgical care in Vanuatu is an important first step towards developing formal strategies for improving surgical services at the country level.

Naso-enteric Tube Placement: A Review of Methods to Confirm Tip Location, Global Applicability and Requirements.

BACKGROUND: The insertion of a tube through the nose and into the stomach or beyond is a common clinical procedure for feeding and decompression. The safety, accuracy and reliability of tube insertion and methods used to confirm the location of the naso-enteric tube (NET) tip have not been systematically reviewed. The aim of this study is to review and compare these methods and determine their global applicability by end-user engagement. METHODS: A systematic literature review of four major databases was performed to identify all relevant studies. The methods for NET tip localization were then compared for their accuracy with reference to a gold standard method (radiography or endoscopy). The global applicability of the different methods was analysed using a house of quality matrix. RESULTS: After applying the inclusion and exclusion criteria, 76 articles were selected. Limitations were found to be associated with the 20 different methods described for NET tip localization. The method with the best combined sensitivity and specificity (where n > 1) was ultrasound/sonography, followed by external magnetic guidance, electromagnetic methods and then capnography/capnometry. The top three performance criteria that were considered most important for global applicability were cost per tube/disposable, success rate and cost for non-disposable components. CONCLUSION: There is no ideal method for confirming NET tip localisation. While radiography (the gold standard used for comparison) and ultrasound were the most accurate methods, they are costly and not universally available. There remains the need to develop a low-cost, easy-use, accurate and reliable method for NET tip localization.

Classifying the severity of acute pancreatitis: towards a way forward.

BACKGROUND: The recent development of two different severity classifications for acute pancreatitis has appropriately raised questions about which should be used. The aim of this paper is to review the two new severity classifications, outline their differences, review validation studies, and identify gaps in knowledge to suggest a way forward. METHODS: A literature review was performed to identify the purposes and differences between the classifications. Validation studies and those comparing the two different classifications were also reviewed. RESULTS: The Revised Atlanta Classification (RAC) and the Determinants Based Classification (DBC) both rely on assessment of local and systemic factors. The differences between the classifications provides opportunities for further research to improve the accuracy and utility of severity classification. This includes understanding how best to tailor severity classification to setting (e.g. secondary or tertiary hospital) and purpose (e.g. clinical management or research). A key difference is that the RAC does not consider infected pancreatic necrosis an indicator of severe disease. There is also the need to develop methods for the accurate non-invasive diagnosis of infected necrosis and evaluation of the characteristics of organ dysfunction in relation to severity and outcome. CONCLUSION: Further improvement in severity classification is possible and research priorities have been identified. For now, the decision as to which classification to use should be on the basis of setting, validity, accuracy, and ease of use.

Meta-analysis of gut barrier dysfunction in patients with acute pancreatitis.

BACKGROUND: The gut is implicated in the pathogenesis of acute pancreatitis but there is discrepancy between individual studies regarding the prevalence of gut barrier dysfunction in patients with acute pancreatitis. The aim of this study was to determine the prevalence of gut barrier dysfunction in acute pancreatitis, the effect of different co-variables, and changes in gut barrier function associated with the use of various therapeutic modalities. METHODS: A literature search was performed using PRISMA and MOOSE guidelines. Summary estimates were presented as pooled prevalence of gut barrier dysfunction and the associated 95 per cent c.i. RESULTS: A total of 44 prospective clinical studies were included in the systematic review, of which 18 studies were subjected to meta-analysis. The pooled prevalence of gut barrier dysfunction was 59 (95 per cent c.i. 48 to 70) per cent; the prevalence was not significantly affected by disease severity, timing of assessment after hospital admission or type of test used, but showed a statistically significant association with age. Overall, nine of 13 randomized clinical trials reported a significant improvement in gut barrier function following intervention compared with the control group, but only three of six studies that used standard enteral nutrition reported a statistically significant improvement in gut barrier function after intervention. CONCLUSION: Gut barrier dysfunction is present in three of five patients with acute pancreatitis, and the prevalence is affected by patient age but not by disease severity. Clinical studies are needed to evaluate the effect of enteral nutrition on gut function in acute pancreatitis.

Systematic review of skills transfer after surgical simulation-based training.

BACKGROUND: Simulation-based training assumes that skills are directly transferable to the patient-based setting, but few studies have correlated simulated performance with surgical performance. METHODS: A systematic search strategy was undertaken to find studies published since the last systematic review, published in 2007. Inclusion of articles was determined using a predetermined protocol, independent assessment by two reviewers and a final consensus decision. Studies that reported on the use of surgical simulation-based training and assessed the transferability of the acquired skills to a patient-based setting were included. RESULTS: Twenty-seven randomized clinical trials and seven non-randomized comparative studies were included. Fourteen studies investigated laparoscopic procedures, 13 endoscopic procedures and seven other procedures. These studies provided strong evidence that participants who reached proficiency in simulation-based training performed better in the patient-based setting than their counterparts who did not have simulation-based training. Simulation-based training was equally as effective as patient-based training for colonoscopy, laparoscopic camera navigation and endoscopic sinus surgery in the patient-based setting. CONCLUSION: These studies strengthen the evidence that simulation-based training, as part of a structured programme and incorporating predetermined proficiency levels, results in skills transfer to the operative setting.

[International multidisciplinary classification of acute pancreatitis severity: the 2013 Spanish edition]. / Clasificación Internacional y Multidisciplinaria de la Pancreatitis Aguda: Edición Española 2013.

OBJECTIVE: To develop a new classification of acute pancreatitis severity on the basis of a sound conceptual framework, comprehensive review of the published evidence, and worldwide consultation. BACKGROUNDS: The Atlanta definitions of acute pancreatitis severity are ingrained in the lexicon of specialist in pancreatic diseases, but are suboptimal because these definitions are based on the empiric description of events not associated with severity. METHODS: A personal invitation to contribute to the development of a new classification of acute pancreatitis severity was sent to all surgeons, gastroenterologists, internists, intensivists and radiologists currently active in the field of clinical acute pancreatitis. The invitation was not limited to members of certain associations or residents of certain countries. A global web-based survey was conducted, and a dedicated international symposium was organized to bring contributors from different disciplines together and discuss the concept and definitions. RESULTS: The new classification of severity is based on the actual local and systemic determinants of severity, rather than on the description of events that are non-causally associated with severity. The local determinant relates to whether there is (peri) pancreatic necrosis or not, and if present, whether it is sterile or infected. The systemic determinant relates to whether there is organ failure or not, and if present, whether it is transient or persistent. The presence of one determinant can modify the effect of another, whereby the presence of both infected (peri) pancreatic necrosis and persistent organ failure has a greater impact upon severity than either determinant alone. The derivation of a classification based on the above principles results in four categories of severity: mild, moderate, severe, and critical. CONCLUSIONS: This classification is the result of a consultative process among specialists in pancreatic diseases from 49 countries spanning North America, South America, Europe, Asia, Oceania and Africa. It provides a set of concise up to date definitions of all the main entities pertinent to classifying the severity of acute pancreatitis in clinical practice and research. This ensures that the determinant-based classification can be used in a uniform manner throughout the world.

[Multidisciplinar international classification of the severity of acute pancreatitis: Italian version 2013]. / Classificazione Internazionale Multidisciplinare della Gravità della Pancreatite Acuta Versione Italiana 2013.

AIM: The aim of this paper was to present the 2013 Italian edition of a new international classification of acute pancreatitis severity. The Atlanta definitions of acute pancreatitis severity are ingrained in the lexicon of pancreatologists but suboptimal because these definitions are based on empiric description of occurrences that are merely associated with severity. METHODS: A personal invitation to contribute to the development of a new international classification of acute pancreatitis severity was sent to all surgeons, gastroenterologists, internists, intensivists, and radiologists who are currently active in clinical research on acute pancreatitis. A global web-based survey was conducted and a dedicated international symposium was organized to bring contributors from different disciplines together and discuss the concept and definitions. RESULTS: The new international classification is based on the actual local and systemic determinants of severity, rather than description of events that are correlated with severity. The local determinant relates to whether there is (peri)pancreatic necrosis or not, and if present, whether it is sterile or infected. The systemic determinant relates to whether there is organ failure or not, and if present, whether it is transient or persistent. The presence of one determinant can modify the effect of another such that the presence of both infected (peri)pancreatic necrosis and persistent organ failure have a greater effect on severity than either determinant alone. The derivation of a classification based on the above principles results in 4 categories of severity-mild, moderate, severe, and critical. CONCLUSION: This classification provides a set of concise up-to-date definitions of all the main entities pertinent to classifying the severity of acute pancreatitis in clinical practice and research.

[Determinant-based classification of acute pancreatitis severity. International multidisciplinary classification of acute pancreatitis severity: the 2013 German edition]. / Einteilung des Schweregrads der akuten Pankreatitis. Internationale, multidisziplinäre klinische Klassifikation auf Basis pathogenetischer Determinanten: Deutsche Version 2013.

OBJECTIVE: The aim of this study was to develop a new international classification of acute pancreatitis severity on the basis of a sound conceptual framework, comprehensive review of published evidence, and worldwide consultation. BACKGROUND: The Atlanta definitions of acute pancreatitis severity are ingrained in the lexicon of pancreatologists but suboptimal because these definitions are based on empiric descriptions of occurrences that are merely associated with severity. METHODS: A personal invitation to contribute to the development of a new international classification of acute pancreatitis severity was sent to all surgeons, gastroenterologists, internists, intensive medicine specialists, and radiologists who are currently active in clinical research on acute pancreatitis. The invitation was not limited to members of certain associations or residents of certain countries. A global Web-based survey was conducted and a dedicated international symposium was organised to bring contributors from different disciplines together and discuss the concept and definitions. RESULT: The new international classification is based on the actual local and systemic determinants of severity, rather than descriptions of events that are correlated with severity. The local determinant relates to whether there is (peri)pancreatic necrosis or not, and if present, whether it is sterile or infected. The systemic determinant relates to whether there is organ failure or not, and if present, whether it is transient or persistent. The presence of one determinant can modify the effect of another such that the presence of both infected (peri)pancreatic necrosis and persistent organ failure have a greater effect on severity than either determinant alone. The derivation of a classification based on the above principles results in 4 categories of severity - mild, moderate, severe, and critical. CONCLUSIONS: This classification is the result of a consultative process amongst pancreatologists from 49 countries spanning North America, South America, Europe, Asia, Oceania, and Africa. It provides a set of concise up-to-date definitions of all the main entities pertinent to classifying the severity of acute pancreatitis in clinical practice and research. This ensures that the determinant-based classification can be used in a uniform manner throughout the world.

Rapid high-amplitude circumferential slow wave propagation during normal gastric pacemaking and dysrhythmias.

BACKGROUND: Gastric slow waves propagate aborally as rings of excitation. Circumferential propagation does not normally occur, except at the pacemaker region. We hypothesized that (i) the unexplained high-velocity, high-amplitude activity associated with the pacemaker region is a consequence of circumferential propagation; (ii) rapid, high-amplitude circumferential propagation emerges during gastric dysrhythmias; (iii) the driving network conductance might switch between interstitial cells of Cajal myenteric plexus (ICC-MP) and circular interstitial cells of Cajal intramuscular (ICC-IM) during circumferential propagation; and (iv) extracellular amplitudes and velocities are correlated. METHODS: An experimental-theoretical study was performed. High-resolution gastric mapping was performed in pigs during normal activation, pacing, and dysrhythmia. Activation profiles, velocities, and amplitudes were quantified. ICC pathways were theoretically evaluated in a bidomain model. Extracellular potentials were modeled as a function of membrane potentials. KEY RESULTS: High-velocity, high-amplitude activation was only recorded in the pacemaker region when circumferential conduction occurred. Circumferential propagation accompanied dysrhythmia in 8/8 experiments was faster than longitudinal propagation (8.9 vs 6.9 mm s(-1) ; P = 0.004) and of higher amplitude (739 vs 528 µV; P = 0.007). Simulations predicted that ICC-MP could be the driving network during longitudinal propagation, whereas during ectopic pacemaking, ICC-IM could outpace and activate ICC-MP in the circumferential axis. Experimental and modeling data demonstrated a linear relationship between velocities and amplitudes (P < 0.001). CONCLUSIONS & INFERENCES: The high-velocity and high-amplitude profile of the normal pacemaker region is due to localized circumferential propagation. Rapid circumferential propagation also emerges during a range of gastric dysrhythmias, elevating extracellular amplitudes and organizing transverse wavefronts. One possible explanation for these findings is bidirectional coupling between ICC-MP and circular ICC-IM networks.

'Artery-first' approaches to pancreatoduodenectomy.

BACKGROUND: The technique of pancreatoduodenectomy (PD) has evolved. Previously, non-resectability was determined by involvement of the portal vein-superior mesenteric vein. Because venous resection can be achieved safely and with greater awareness of the prognostic significance of the status of the posteromedial resection margin, non-resectability is now determined by involvement of the superior mesenteric artery (SMA). This change, with a need for early determination of resectability before an irreversible step, has promoted the development of an 'artery-first' approach. The aim of this study was to review, and illustrate, this approach. METHODS: An electronic search was performed on MEDLINE, Embase and PubMed databases from 1960 to 2011 using both medical subject headings and truncated word searches to identify all published articles that related to this topic. RESULTS: The search revealed six different surgical approaches that can be considered as 'artery first'. These involved approaching the SMA from the retroperitoneum (posterior approach), the uncinate process (medial uncinate approach), the infracolic region medial to the duodenojejunal flexure (inferior infracolic or mesenteric approach), the infracolic retroperitoneum lateral to the duodenojenunal flexure (left posterior approach), the supracolic region (inferior supracolic approach) and through the lesser sac (superior approach). CONCLUSION: The six approaches described provide a range of options for the early determination of arterial involvement, depending on the location and size of the tumour, and before the 'point of no return'. Whether these approaches will achieve an increase in the proportion of patients with negative margins, improve locoregional control and increase long-term survival has yet to be determined.

Mortality risk stratification in severely anaemic Jehovah's Witness patients.

The aim of this retrospective cohort study was to identify early risk factors of mortality and develop a mortality risk stratification instrument for severely anaemic Jehovah's Witness patients. It has been shown that Jehovah's Witness patients with the Auckland Anaemia Mortality Risk Score (Auckland AMRS) of 0 to 3 had 4% mortality, Auckland AMRS 4 to 5 32%, Auckland AMRS 6 to 7 50% and Auckland AMRS 8 and above 83%. It is concluded that the Auckland AMRS predicts mortality of severely anaemic Jehovah's Witness patients.