Feeding en route: Prey availability and traits influence prey selection by an avian predator on migration.

During animal migration, ephemeral communities of taxa at all trophic levels co-occur over space and time. The interactions between predators and prey along migration corridors are ecologically and evolutionarily significant. However, these interactions remain understudied in terrestrial systems and warrant further investigations using novel approaches. We investigated the predator-prey interactions between a migrating avivorous predator and ephemeral avian prey community in the fall migration season. We tested for associations between avian traits and prey selection and hypothesized that prey traits (i.e. relative size, flocking behaviour, habitat, migration tendency and availability) would influence prey selection by a sexually dimorphic raptor on migration. To document prey consumption, we sampled trace prey DNA from beaks and talons of migrating sharp-shinned hawks Accipiter striatus (n = 588). We determined prey availability in the ephemeral avian community by extracting weekly abundance indices from eBird Status and Trends data. We used discrete choice models to assess prey selection and visualized the frequency of prey in diet and availability on the landscape over the fall migration season. Using eDNA metabarcoding, we detected prey species on 94.1% of the hawks sampled (n = 525/588) comprising 1396 prey species detections from 65 prey species. Prey frequency in diet and eBird relative abundance of prey species were correlated over the migration season for top-selected prey species, suggesting prey availability is an important component of raptor-songbird interactions during fall. Prey size, flocking behaviour and non-breeding habitat association were prey traits that significantly influenced predator choice. We found differences between female and male hawk prey selection, suggesting that sexual size dimorphism has led to distinct foraging strategies on migration. This research integrated field data collected by a volunteer-powered raptor migration monitoring station and public-generated data from eBird to reveal elusive predator-prey dynamics occurring in an ephemeral raptor-songbird community during fall migration. Understanding dynamic raptor-songbird interactions along migration routes remains a relatively unexplored frontier in animal ecology and is necessary for the conservation and management efforts of migratory and resident communities.

Durante la migración animal, las comunidades efímeras de taxones de todos los niveles tróficos coexisten en el espacio y el tiempo. Las interacciones entre depredadores y presas a lo largo de los corredores migratorios son significativas desde el punto de vista ecológica y evolutivo. Sin embargo, estas interacciones siguen siendo poco estudiadas en los sistemas terrestres y justifican más investigaciones utilizando enfoques novedosos. Investigamos las interacciones depredador­presa entre un depredador avívoro migratorio y una comunidad de presas aviares efímeras en la temporada migratoria otoñal. Probamos las asociaciones entre los rasgos de las aves y la selección de presas y planteamos la hipótesis de que los rasgos de las presas (tamaño relativo, comportamiento de bandada, hábitat, tendencia migratoria y disponibilidad) influirían en la selección de presas por parte de una rapaz sexualmente dimórfica durante la migración. Para documentar el consumo de presas, recogimos rastros de ADN de presas de picos y garras de Gavilán Americano Accipiter striatus (n = 588) migratorios. Determinamos la disponibilidad de presas en la comunidad de aves efímeras extrayendo índices de abundancia semanales de los datos de eBird Estado y Tendencias. Utilizamos modelos de elección discreta para evaluar la selección de presas y visualizamos la frecuencia de las presas en la dieta y la disponibilidad en el paisaje durante la temporada migratoria otoñal. Utilizando el metacódigo de barras del ADN ambiental, detectamos especies de presas en el 94,1% de los halcones muestreados (n = 525/588), comprendiendo 1396 detecciones de 65 especies de presas. La frecuencia de presas en la dieta y la abundancia relativa de especies de presas en eBird se correlacionaron a lo largo de la temporada de migración para las principales especies de presas seleccionadas, lo que sugiere que la disponibilidad de presas es un componente importante de las interacciones entre aves rapaces y aves canoras durante el otoño. El tamaño de las presas, el comportamiento de las bandadas y la asociación con el hábitat no reproductivo fueron rasgos de presa que influyeron significativamente en la elección de los depredadores. Encontramos diferencias entre la selección de presas de gavilán hembra y macho, lo que sugiere que el dimorfismo sexual de tamaño ha conducido a distintas estrategias de alimentación durante la migración. Esta investigación integró datos de campo recopilados por una estación de monitoreo de migración de rapaces impulsada por voluntarios y datos generados públicamente por eBird para revelar la esquiva dinámica depredador­presa que ocurre en una comunidad efímera de rapaces y aves canoras durante la migración otoñal. Comprender las interacciones dinámicas entre rapaces y aves canoras a lo largo de las rutas migratorias sigue siendo una frontera relativamente inexplorada en la ecología animal y es necesaria para los esfuerzos de conservación y gestión de las comunidades migratorias y residentes.

Hemolytic parasites affect survival in migrating red-tailed hawks.

Migrating birds face a myriad of hazards, including higher exposure to parasites and numerous competing energy demands. It follows that migration may act as a selective filter and limit population growth. Understanding how individual-level physiological condition and disease status scale up to population dynamics through differential survival of individuals is necessary to identify threats and management interventions for migratory populations, many of which face increasing conservation challenges. However, linking individual physiological condition, parasite infection status and survival can be difficult. We examined the relationship among two measures of physiological condition [scaled-mass index and heterophil/leukocyte (H/L) ratio], hematozoa (i.e. hemoparasites) presence and abundance, and constitutive immunity in 353 autumn migrating red-tailed hawks (Buteo jamaicensis calurus) from 2004 to 2018. Hematazoa (i.e. Haemoproteus and Leucocytozoon) were in the blood smears from 139 red-tailed hawks (39.4%). H/L ratio decreased with scaled-mass index. Adults had a significantly higher H/L ratio than juveniles. Our two measures of immune defences, hemolytic-complement activity and bacteria-killing ability, were highly positively correlated. Our most notable finding was a negative relationship between Haemoproteus parasitemia and survival (i.e. documented individual mortality), indicating that haemosporidian parasites influence survival during a challenging life stage. The effect of haemosporidian parasites on individuals is often debated, and we provide evidence that parasitemia can affect individual survival. In contrast, we did not find evidence of trade-offs between survival and immune defences.

Snap-freezing in the Field: Effect of Sample Holding Time on Performance of Bactericidal Assays.

Comparative analyses in biology rely on the quality of available data. Methodological differences among studies may introduce variation in results that obscure patterns. In the field of eco-immunology, functional immune assays such as antimicrobial capacity assays are widely used for among-species applications. Sample storage time and animal handling time can influence assay results in some species, but how sample holding time prior to freezing influences assay results is unknown. Sample holding time can vary widely in field studies on wild animals, prompting the need to understand the implications of such variation on assay results. We investigated the hypothesis that sample holding time prior to freezing influences assay results in six species (Leiocephalus carinatus, Iguana iguana, Loxodonta africana, Ceratotherium simum, Columba livia, and Buteo swainsoni) by comparing antibacterial capacity of serum with varying processing times prior to snap-freezing. Blood was collected once from each individual and aliquots were placed on ice and assigned different holding times (0, 30, 60, 180, and 240 min), after which each sample was centrifuged, then serum was separated and snap-frozen on dry ice and stored at -80ºC for 60 days prior to assaying. For each aliquot, we conducted antibacterial capacity assays with serial dilutions of serum inoculated with E. coli and extracted the dilution at 50% antibacterial capacity for analysis. We found a decrease in antibacterial capacity with increased holding time in one of the six species tested (B. swainsoni), driven in part by complete loss of antibacterial capacity in some individuals at the 240-min time point. While the majority of species' antibacterial capacity were not affected, our results demonstrate the need to conduct pilot assays spanning the anticipated variation in sample holding times to develop appropriate field protocols.

Impact of SARS-CoV-2 pandemic on pancreatic cancer services and treatment pathways: United Kingdom experience.

INTRODUCTION: The SARS-CoV-2 pandemic presented healthcare providers with an extreme challenge to provide cancer services. The impact upon the diagnostic and treatment capacity to treat pancreatic cancer is unclear. This study aimed to identify national variation in treatment pathways during the pandemic. METHODS: A survey was distributed to all United Kingdom pancreatic specialist centres, to assess diagnostic, therapeutic and interventional services availability, and alterations in treatment pathways. A repeating methodology enabled assessment over time as the pandemic evolved. RESULTS: Responses were received from all 29 centres. Over the first six weeks of the pandemic, less than a quarter of centres had normal availability of diagnostic pathways and a fifth of centres had no capacity whatsoever to undertake surgery. As the pandemic progressed services have gradually improved though most centres remain constrained to some degree. One third of centres changed their standard resectable pathway from surgery-first to neoadjuvant chemotherapy. Elderly patients, and those with COPD were less likely to be offered treatment during the pandemic. CONCLUSION: The COVID-19 pandemic has affected the capacity of the NHS to provide diagnostic and staging investigations for pancreatic cancer. The impact of revised treatment pathways has yet to be realised.

Lung-protective ventilation vs conventional ventilation in emergency surgery.

Lung-protective ventilation significantly reduces mortality in patients with acute respiratory distress syndrome, but do the advantages of this approach transfer from the intensive care unit to the operating room?

Chlamydia (lymphogranuloma venereum) peritonitis in a male patient.

A 49-year-old man presented with a 1-week history of abdominal pain, distension, diarrhoea and fatigue. CT of the abdomen and pelvis revealed peritonitis with no identifiable cause. Diagnostic laparoscopy was performed, which excluded gastrointestinal perforation. Peritoneal fluid tested positive for Chlamydia trachomatis and rectal swabs were positive for C. trachomatis serovars consistent with lymphogranuloma venereum (LGV). Additional blood tests also revealed a diagnosis of syphilis. This is a rare documented case of LGV peritonitis in a male without associated immunodeficiency. The patient recovered well following laparoscopic washout and a course of appropriate antibiotics.

Chyle leak following pancreatico-duodenectomy: a tertiary hepatopancreaticobiliary unit's experience and a proposed management algorithm.

BACKGROUND: Chyle leak (CL) is an uncommon complication of pancreatico-duodenectomy (PD). Its incidence, risk factors, and effect on prognosis are not well described and optimum management remains debated. This study aims to calculate incidence of CL following PD and identify risk factors. Following a literature review, we have proposed a management algorithm. METHODS: This is a retrospective review of all patients who underwent PD between January 2006 and April 2020 at a tertiary hepatopancreaticobiliary unit in the UK. The following data were obtained: age, gender, American Society of Anesthesiologists grade, body mass index, co-morbidities, duration of surgery, tumour histology, length of stay and mortality. RESULTS: A total of 560 patients were included. Seventeen developed CL (3.04%). Median age was 64 years (range 50-81). Sixteen (94.1%) patients still had their surgical drain in at the time of CL diagnosis. One (5.9%) did not and had free intra-abdominal fluid on computed tomography; a diagnosis was made after an ultrasound-guided drain had been inserted. CL patients were more likely to have higher body mass index (mean 30.5 kg/m2 (range 17-43) versus 26.7 kg/m2 (22-38)) (P = 0.02) and longer duration of operation (mean 6.2 h (range 4.3-9.0) versus 5.6 (3.0-11.0)) (P = 0.03). All cases of CL resolved without operative intervention. CL did not affect length of stay (median 10 days (range 4-41) versus 11 (4-34)). CONCLUSIONS: In our series, 3.04% of patients who underwent PD developed CL. No patients required a return to theatre, and none had CL recurrence.

Seasonal muscle ultrastructure plasticity and resistance of muscle structural changes during temperature increases in resident black-capped chickadees and rock pigeons.

Resident birds in temperate zones respond to seasonally fluctuating temperatures by adjusting their physiology, such as changes in basal metabolic rate or peak metabolic rate during cold exposure, or altering their organ sizes, so as to match the thermogenic requirements of their current environment. Climate change is predicted to cause increases in the frequency of heat and cold wave events, which could increase the likelihood that birds will face an environmental mismatch. Here, we examined seasonality and the effects of acute and chronic heat shock to 33°C and subsequent recovery from heat shock on the ultrastructure of the superficial pectoralis muscle fiber diameter, myonuclear domain (MND) and capillary density in two temperate bird species of differing body mass, the black-capped chickadee (Poecile atricapillus) and the rock pigeon (Columba livia). We found that muscle fiber ultrastructure did not change with heat treatment. However, in black-capped chickadees, there was a significant increase in fiber diameter in spring phenotype birds compared with summer phenotype birds. In rock pigeons, we saw no differences in fiber diameter across seasons. Capillary density did not change as a function of fiber diameter in black-capped chickadees, but did change seasonally, as did MND. Across seasons, as fiber diameter decreased, capillary density increased in the pectoralis muscle of rock pigeons. For both species in this study, we found that as fiber diameter increased, so did MND. Our findings imply that these two temperate birds employ different muscular growth strategies that may be metabolically beneficial to each.

Anatomical variation of arterial blood supply of liver segment IV

There has been a dilemma about the arterial supply of segment IV of the liver, and the subsequent risk of ischaemia, necrosis, hepatic artery thrombosis of segment IV after split-liver transplantation or the associating liver partition and portal vein ligation for staged hepatectomy procedure. We report a rare case of anatomical variation of the arterial blood supply of segment IV of the liver. In this case the proper hepatic artery trifurcated into left, middle and right branches that supplied the liver. Moreover, Segment IV received dual blood supply from both, the middle hepatic artery and the right branch of the proper hepatic artery. Identifying such anatomical variation prior to any liver surgery is essential. It is of particular significance in defining the resection line in liver surgeries. In order to avoid ischaemia, necrosis or cholangiopathy in segment IV, the division of liver parenchyma needs to be based on the anatomy of the arterial blood supply and the intrahepatic blood distribution to segment IV

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Comparison of lipase and amylase for diagnosing post-operative pancreatic fistulae.

BACKGROUND: To ascertain if post-operative drain fluid lipase is superior to amylase in routinely detecting clinically significant post-operative pancreatic fistulae (POPF). METHOD: Between January 2015 and March 2016 data were collected on all patients undergoing pancreatic surgery at a regional referral centre. Routine drain fluid analysis was performed on post-operative patients as part of a locally defined enhanced recovery protocol. POPF was diagnosed in accordance with the recently updated International Study Group of Pancreatic Surgery guidance. RESULTS: During the study period, there were 68 pancreatic resections. The median age was 69.1 years. A total of 11 (15.9%) patients developed clinically significant POPF (nine type B and two type C). The median drain amylase result in patients with type B or C leak was 532 IU/L (interquartile range (IQR) 264-833). This was significantly higher than those without a clinical fistula (median 38, IQR 15-376, P = 0.012). The median drain lipase result was 1504 IU/L (IQR 746-2236). This was significantly higher than those without a clinical fistula (median 57, IQR 13-1277, P = 0.012). Fluid amylase had a sensitivity of 81.8% and specificity of 69.2%; fluid lipase had a sensitivity of 91% and specificity of 64.9%. CONCLUSION: Our experience suggests drain fluid amylase or lipase results are not sufficiently sensitive or specific to reassure clinicians and rule out clinically significant POPF. However, if biochemical tests are used to aid decision-making, then lipase is a more sensitive biochemical marker than amylase for the routine detection of clinically significant POPF.

ATYPICAL CHLAMYDIACEAE IN WILD POPULATIONS OF HAWKS ( BUTEO SPP.) IN CALIFORNIA.

Chlamydiaceae bacteria infect many vertebrate hosts, and previous reports based on polymerase chain reaction (PCR) assays and serologic assays that are prone to cross-reaction among chlamydial organisms have been used to describe the prevalence of either DNA fragments or antibodies to Chlamydia spp. in wild raptorial populations. This study reports the PCR-based prevalence of Chlamydiaceae DNA that does not 100% match any avian or mammalian Chlamydiaceae in wild populations of hawks in California Buteo species. In this study, multimucosal swab samples ( n = 291) for quantitative PCR (qPCR) and plasma ( n = 78) for serology were collected from wild hawks. All available plasma samples were negative for antibodies using a C. psittaci-specific elementary body agglutination test (EBA; n = 78). For IgY antibodies all 51 available samples were negative using the indirect immunofluorescent assay. The overall prevalence of Chlamydiaceae DNA detection in wild Buteo species sampled was 1.37% (4/291) via qPCR-based analysis. Two fledgling Swainson's hawks ( Buteo swainsoni) and two juvenile red-tailed hawks ( Buteo jamaicensis) were positive by qPCR-based assay for an atypical chlamydial sequence that did not 100% match any known C. psittaci genotype. Positive swab samples from these four birds were sequenced based on the ompA gene and compared by high-resolution melt analysis with all known avian and mammalian Chlamydiaceae. The amplicon sequence did not 100% match any known avian chlamydial sequence; however, it was most similar (98.6%) to C. psittaci M56, a genotype that is typically found in muskrats and hares. Culture and full genome sequence analysis of Chlamydia spp. isolated from diseased hawks will be necessary to classify this organism and to better understand its epizootiology and potential health impact on wild Buteo populations in California.

Anatomical variations of the renal arterial vasculature: An Australian perspective.

INTRODUCTION: Variations of the renal arteries have been studied and published across various population groups, but similar information for the ethnically diverse nation of Australia is lacking. This study describes the pattern of renal artery anomalies in a section of the Australian population based on computed tomography (CT) angiograms of the abdomen and cadaveric dissection. METHODS: The renal arterial vasculature of 594 kidneys from 300 subjects (28 cadavers, 272 CT) was studied. The number and pattern of renal arteries were categorised on the basis of laterality, point of origin and termination in the kidney (superior pole, hilum and inferior pole), symmetry and sex. RESULTS: Multiple renal arteries were discovered in 22% of subjects and 12.12% of kidneys. The most common pattern observed was the presence of one variant renal artery (93.1%), compared to the finding of two (5.6%) and three (1.4%) multiple arteries. The aorta was the most frequent site of origin for anomalous vessels, while the hilum was the predominant point of entry. No significant difference was established between left- and right-sided kidneys (13.8% vs. 12.5%; P = 0.627); however, unilateral distribution was more common than bilateral additional renal arteries (16.7% vs. 3.4%; P < 0.01), and variations among males were more than females (27.2% vs. 15.2%; P < 0.05). A higher rate of multiple renal arteries was noted in cadaveric dissections compared to CT images (46.4% vs. 19.5%; P < 0.01). CONCLUSION: These findings provide application of an evidence-based teaching tool that facilitates education regarding renal arterial variations in Australia.

The effect of post-mortem computed tomography angiography (PMCTA) using water-soluble, iodine-based radiographic contrast on histological analysis of the liver, kidneys and left ventricle of the heart.

The purpose of this study was to investigate the impact of post-mortem computed-tomography angiography (PMCTA) on the histology of the liver, kidneys and heart. Multiple tissue cores were collected from the liver, left and right kidneys and left ventricle utilizing CT-guided biopsy. Subsequent whole body PMCTA was performed using a solution of polyethylene glycol and iodinated radiographic contrast, and an embalming pump. Corresponding biopsy cores were collected at autopsy, and blinded histology analysis assessing for PMCTA-induced histology artefact was performed. The blinded analysis of pre-PMCTA and post-PMCTA biopsy samples demonstrated that whole body PMCTA had no effect on the histological analyses of the liver (0%, CI = 0-13.7%), left ventricle of the heart (0%, CI = 0-36.9%) and right kidney (0%, CI = 13.2%), however likely caused increased Bowman's capsule spaces in the left kidney of one case (4%, CI = 0.01-20.4%). Other artefactual histological changes identified included eosinophilic material in the liver, whiter interstitium and dilated tubules in kidney samples, and autolysis-related changes, however these could not be categorically attributed to the PMCTA procedure. PMCTA causes zero or minimal effect to the histological examination of the liver, left kidney, right kidney and left ventricle, and as such performing PMCTA prior to autopsy is unlikely to impact autopsy histological results in these organs.

Variation in survival after surgery for peri-ampullary cancer in a regional cancer network.

BACKGROUND: Centralisation of specialist surgical services requires that patients are referred to a regional centre for surgery. This process may disadvantage patients who live far from the regional centre or are referred from other hospitals by making referral less likely and by delaying treatment, thereby allowing tumour progression. The aim of this study is to explore the outcome of surgery for peri-ampullary cancer (PC) with respect to referring hospital and travel distance for treatment within a network served by five hospitals. METHODS: Review of a unit database was undertaken of patients undergoing surgery for PC between January 2006 and May 2014. RESULTS: 394 patients were studied. Although both the median travel distance for patients from the five hospitals (10.8, 86, 78.8, 54.7 and 89.2 km) (p < 0.05), and the annual operation rate for PC (2.99, 3.29, 2.13, 3.32 and 3.07 per 100,000) (p = 0.044) were significantly different, no correlation was noted between patient travel distance and population operation rate at each hospital. No difference was noted between patients from each hospital in terms of resection completion rate or pathological stage of the resected tumours. The median survival after diagnosis for patients referred from different hospitals ranged from 1.2 to 1.7 years and regression analysis revealed that increased travel distance to the regional centre was associated with a small survival advantage. CONCLUSION: Although variation in the provision and outcome of surgery for PC between regional hospitals is noted, this is not adversely affected by geographical isolation from the regional centre. TRIAL REGISTRATION: This study is part of post-graduate research degree project. The study is registered with ClinicalTrials.gov (unique identifier NCT02296736 ) November 18, 2014.

Differentiating Simple Hepatic Cysts from Mucinous Cystic Neoplasms: Radiological Features, Cyst Fluid Tumour Marker Analysis and Multidisciplinary Team Outcomes.

BACKGROUND: Differentiating hepatic mucinous cystic neoplasms (MCNs) from simple hepatic cysts (SCs) preoperatively is a challenging task. Our aim was to determine whether radiological features on ultrasound scan (USS), CT or MRI, cyst fluid tumour markers, or multidisciplinary team (MDT) outcomes could differentiate MCN from SC. METHODS: A retrospective review of radiological features, cyst fluid tumour marker levels and MDT outcomes in 52 patients was performed. RESULTS: There were 13 patients with MCN, 38 with SC and one ciliated foregut cyst. MCNs were more often solitary (p = 0.006). Although no other individual radiological characteristic on USS, CT or MRI was predictive of MCN, MDT outcomes stating that a cyst was complex in nature were highly predictive (p = 0.0007). Cyst fluid carbohydrate antigen 19-9, carcino-embryonic antigen and cancer antigen 125 were unable to differentiate MCN from SC (p = 0.45, p = 0.49, and p = 0.73, respectively). CONCLUSIONS: MDT outcomes are of greatest value when trying to differentiate MCN from SC, as well as having a solitary cyst on imaging. Conventional cyst fluid tumour markers are unhelpful. All suspicious cystic liver lesions should be discussed pre-operatively by a hepatobiliary MDT to determine the most appropriate surgical approach.

Rebound growth of hepatic colorectal metastases after neo-adjuvant chemotherapy: effect on survival after resection.

BACKGROUND: A period of recovery is commonly allowed between completion of chemotherapy for colorectal liver metastases (CRLM) and resection, during which tumour progression may occur. The study-aim is to assess the growth of CRLM in this interval and association with outcome. METHOD: Data on 146 patients were analysed. Change in tumour size was assessed by comparing size determined by imaging performed on completion of chemotherapy with that determined by examination of the resected specimen, categorised by RECIST criteria. RESULTS: In the interval before surgery sixteen patients (11%) fulfilled criteria for partial response (PR), 48 (33%) had stable disease (SD) and 82 (56%) had progressive disease (PD). Among patients with PD following chemotherapy the median disease-free survival of patients who initially responded (26 months) was longer than in those who initially had stable disease (7 months) (P = 0.002). No association was noted between rate of tumour growth after completion of chemotherapy and disease-free survival. CONCLUSION: Change in tumour size after completion of chemotherapy is variable and can be rapid, especially in patients who initially respond to treatment. However, disease-free survival is determined by tumour behaviour during treatment and not by change in size after completion of chemotherapy.

Assessment of the effect of interval from presentation to surgery on outcome in patients with peri-ampullary malignancy.

BACKGROUND: Delay between diagnosis of peri-ampullary cancer (PC) and surgery may allow tumour progression and affect outcome. The aim of this study was to explore associations of interval to surgery (IS) with pathological outcomes and survival in patients with PC. METHOD: A database review of all patients undergoing surgery between 2006 and 2014 was undertaken. IS was measured from diagnosis by imaging. Potential association between IS and survival was measured using Cox regression analysis, and between IS and pathological outcome with multivariate logistic analysis. RESULTS: 388 patients underwent surgery. The median IS was 49 days (1-551 days), and was not associated with any of the evaluated outcomes in patients with pancreatic (149) or distal bile duct (46) cancer. For patients with ampullary cancer (71) longer IS was associated with improved survival, with median survival of 27.5 months for patients waiting ≤ median IS (35) and 38.3 months for patients waiting > median IS (36) for surgery (p = 0.041). A higher rate of margin positivity (31.4%) was also noted among patients who waited less than the median IS compared to those waiting longer than this interval (11.4%) (p = 0.032). CONCLUSION: For patients with ampullary cancer there is a paradoxical improvement in outcome among those with a longer IS, which may be explained by progression to inoperability of more aggressive lesions.

Delayed diagnosis of alpha-1-antitrypsin deficiency following post-hepatectomy liver failure: A case report.

Post-hepatectomy liver failure (PHLF) is a leading cause of morbidity and mortality following major liver resection. The development of PHLF is dependent on the volume of the remaining liver tissue and hepatocyte function. Without effective pre-operative assessment, patients with undiagnosed liver disease could be at increased risk of PHLF. We report a case of a 60-year-old male patient with PHLF secondary to undiagnosed alpha-1-antitrypsin deficiency (AATD) following major liver resection. He initially presented with acute large bowel obstruction secondary to a colorectal adenocarcinoma, which had metastasized to the liver. There was no significant past medical history apart from mild chronic obstructive pulmonary disease. After colonic surgery and liver directed neo-adjuvant chemotherapy, he underwent a laparoscopic partially extended right hepatectomy and radio-frequency ablation. Post-operatively he developed PHLF. The cause of PHLF remained unknown, prompting re-analysis of the histology, which showed evidence of AATD. He subsequently developed progressive liver dysfunction, portal hypertension, and eventually an extensive parastomal bleed, which led to his death; this was ultimately due to a combination of AATD and chemotherapy. This case highlights that formal testing for AATD in all patients with a known history of chronic obstructive pulmonary disease, heavy smoking, or strong family history could help prevent the development of PHLF in patients undergoing major liver resection.

Clinical assessment before hepatectomy identifies high-risk patients.

BACKGROUND: Liver resection is associated with significant morbidity, and assessment of risk is an important part of preoperative consultations. Objective methods exist to assess operative risk, including cardiopulmonary exercise testing (CPX). Subjective assessment is also made in clinic, and patients perceived to be high-risk are referred for CPX at our institution. This article addresses clinicians' ability to identify patients with a higher risk of surgical complications after hepatectomy, using selection for CPX as a surrogate marker for increased operative risk. MATERIALS AND METHODS: Prospectively collected data on patients undergoing hepatectomy between February 2008 and November 2013 were retrieved and the cohort divided according to CPX referral. Complications were classified using the Clavien-Dindo system. RESULTS: CPX testing was carried out before 101 of 405 liver resections during the study period. The median age was 72 and 64 in CPX and non-CPX groups, respectively (P < 0.001). The resection size was similar between the groups. No difference was noted for grade III complications between CPX and non-CPX tested-groups; however, 19 (18.8%) and 28 (9.2%) patients suffered grade IV-V complications, respectively (P = 0.009). There was no difference in long-term survival between groups (P = 0.63). CONCLUSIONS: This study attempts to assess clinicians' ability to identify patients at greater risk of complications after hepatectomy. The confirmation that patients identified in this way are at greater risk of grade IV-V complications demonstrates the value of preoperative counseling. High-risk patients do not have worse long-term outcomes suggesting survival is determined by other factors, particularly disease recurrence.