The objectives of this prospective, observational study were (1) to determine whether a transplanted liver graft releases proinflammatory cytokines into the systemic circulation upon reperfusion and (2) to determine whether they contribute to any subsequent hemodynamic instability observed after graft reperfusion (if this release occurs). Blood samples from 17 consecutive patients undergoing liver transplantation were analyzed for cytokines, including tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), IL-2, IL-6, and IL-8. Blood samples were obtained from the radial artery, portal vein, and flush blood (a sample taken from a catheter placed above the infrahepatic inferior vena cava clamp). The amount of catecholamines necessary to maintain a mean arterial pressure between 65 and 75 mm Hg during graft reperfusion was compared with the level of cytokines. A statistical analysis was performed with the least squares method, Kendall's tau-b test, and regression analysis. We demonstrated that flush blood from the liver grafts contained a significant amount and variety of cytokines. Most of these were removed by graft irrigation. The concentration of TNF-α in samples obtained from flush blood at the end of liver irrigation was significantly higher than the concentration in samples obtained from the radial artery (P = 0.0067) or portal vein (P = 0.0003) before reperfusion. This correlated directly with the amount of catecholamines used to treat hemodynamic instability. Although there were increased levels of IL-1β, IL-2, and IL-8 in the flush blood, there was no statistically significant correlation between the levels of these cytokines and the amount of catecholamines used. Liver Transpl, 2011. © 2011 AASLD.

Hemodynamic instability (HDI) during liver transplantation (LT) can be difficult to manage and increases postoperative morbidity and mortality. In addition to surgical causes of HDI, patient- and graft-related factors are also important. Nitric oxide–mediated vasodilatation is a common denominator associated with end-stage liver disease related to HDI. Despite intense investigation, optimal management strategies remain elusive. In this consensus article, experts from the International Liver Transplantation Society, the Liver Intensive Care Group of Europe, and the Society for the Advancement of Transplant Anesthesia performed a rigorous review of the most current literature regarding the epidemiology, causes, and management of HDI during LT. Special attention has been paid to unique LT-associated conditions including the causes and management of vasoplegic syndrome, cardiomyopathies, LT-related arrhythmias, right and left ventricular dysfunction, and the specifics of medical and fluid management in end-stage liver disease as well as problems specifically related to portal circulation. When possible, management recommendations are made.

In various medical and surgical specialties, it is essential to acquire fibreoptic upper airway endoscopy skills for successful endotracheal intubation, especially when faced with a difficult airway. The aim of our study was to evaluate the learning curves of residents performing fibreoptic upper airway endoscopy in the simulation environment. Following a standardized video and practice session, 16 residents newly enrolled in the anesthesiology program performed nasal fibreoptic endoscopy of the upper airway (endpoint being the carina) on a high fidelity simulator. Weekly 20-min sessions continued for a period of one month. Each attempt was designated as either a “success” or a “failure” based on the study participant’s ability or inability to visualize the carina in ≤60 sec and with ≤five collisions with the simulated mucosal wall. Proficiency was attained when the downward graphical trend of the cumulative sum (CUSUM) analysis crossed two adjacent boundary lines, i.e., an acceptable failure rate was reached. The residents’ mean number of attempts at fibreoptic airway endoscopy was 47 (9) with a range of 32–64. Time to visualization of the carina was 51 (36) sec. Three classical patterns of CUSUM trends were observed: proficient (n = 7); not proficient with a downward (improvement) trend (n = 3); and not proficient with an upward (worsening) trend (n = 6). The number of attempts at which proficiency was achieved varied from 27 to 58. There is a large variation in the learning curves of residents performing fibreoptic upper airway endoscopy. The training for fibreoptic airway endoscopy should be tailored to the needs of each individual. Dans différentes spécialités médicales et chirurgicales, l’acquisition de compétences en matière d’endoscopie des voies aériennes supérieures par fibre optique est essentielle pour réussir une intubation endotrachéale, particulièrement lorsqu’on est confronté à des voies aériennes difficiles. L’objectif de notre étude était d’évaluer les courbes d’apprentissage des résidents réalisant une endoscopie des voies aériennes supérieures par fibre optique dans un contexte de simulation. Après une séance standardisée de vidéo et de pratique, 16 résidents nouvellement inscrits au programme d’anesthésiologie ont réalisé une endoscopie nasale par fibre optique des voies aériennes supérieures (jusqu’à la carène) sur un simulateur haute fidélité. Des séances hebdomadaires de 20 min se sont poursuivies pendant un mois. Chaque tentative a été considérée comme étant soit une « réussite » ou un « échec » selon la capacité ou l’incapacité du participant à l’étude à visualiser la carène en ≤60 sec et avec ≤cinq collisions contre la paroi muqueuse simulée. La compétence était atteinte lorsque la tendance graphique vers le bas de l’analyse de la somme cumulée (CUSUM) croisait deux lignes de délimitation adjacentes, c.-à-d. qu’un taux d’échec acceptable était atteint. Le nombre moyen de tentatives des résidents pour l’endoscopie des voies aériennes par fibre optique était de 47 (9), avec des résultats allant de 32 à 64. Le temps jusqu’à visualisation de la carène était de 51 (36) sec. Trois schémas classiques de tendances de CUSUM ont été observés : compétent (n = 7); non compétent avec une tendance à la baisse (amélioration) (n = 3); et non compétent avec une tendance à la hausse (aggravation) (n = 6). Le nombre de tentatives pour atteindre la compétence variait de 27 à 58. Il existe une importante variation dans les courbes d’apprentissage des résidents réalisant une endoscopie des voies aériennes supérieures par fibre optique. La formation pour l’endoscopie des voies aériennes par fibre optique devrait être personnalisée selon les besoins de chacun.

In this review, we analyze the epidemiology of thromboses related to end-stage liver disease (ESLD), discuss causes of hypercoagulability, describe susceptible populations, and critically evaluate proposed prophylaxis and treatment of thromboses. Classically, ESLD has been regarded as a model for coagulopathy, and patients were deemed to be at high risk for bleeding complications. Patients with ESLD are not auto-anticoagulated, and they do not have a lower risk of portal vein thrombosis, intracardiac thrombus formation, pulmonary embolism or hepatic artery thrombosis. Though the cause of hypercoagulability is multifactorial, endothelial dysfunction likely plays a central role for all patients with ESLD. Some subpopulations, such as patients with nonalcoholic steatohepatitis and autoimmune conditions, are at increased risk of thrombotic events as are patients of Hispanic ethnicity. The science behind prophylaxis of different types of clotting and treatment of thromboses is developing rapidly. A number of medications, including low molecular weight heparin, unfractionated heparin, aspirin, vitamin K antagonists, and direct oral anticoagulants can be used, but clear guidelines are lacking. Acute intraoperative clotting can be associated with high mortality. Routine use of transesophageal echocardiography can be helpful in early recognition and treatment of intraoperative thrombosis. Heparin should be reserved for cases of intracardiac thrombus/pulmonary embolism without hemodynamic instability. In unstable patients, low dose of recombinant tissue plasminogen activator can be used. In this new era of heightened awareness of thrombotic events in ESLD patients, prospective randomized trials are urgently needed to best guide clinical practice.

End stage liver disease (ESLD) is associated with significant thrombotic complications. In this study, we attempted to determine if patients with ESLD, due to oncologic or autoimmune diseases, are susceptible to thrombosis to a greater extent than patients with ESLD due to other causes. In this retrospective study, we analyzed the UNOS database to determine the incidence of thrombotic complications in orthotopic liver transplant (OLT) recipients with autoimmune and oncologic conditions. Between 2000 and 2012, 65,646 OLTs were performed. We found 4,247 cases of preoperative portal vein thrombosis (PVT) and 1,233 cases of postoperative vascular thrombosis (VT) leading to graft failure. Statistical evaluation demonstrated that patients with either hepatocellular carcinoma (HCC) or autoimmune hepatitis (AIC) had a higher incidence of PVT (p = 0.05 and 0.03 respectively). Patients with primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and AIC had a higher incidence of postoperative VT associated with graft failure (p < 0.0001, p < 0.0001, p = 0.05 respectively). Patients with preoperative PVT had a higher incidence of postoperative VT (p < 0.0001). Multivariable logistic regression demonstrated that patients with AIC, and BMI ≥40, having had a transjugular intrahepatic portosystemic shunt, and those with diabetes mellitus were more likely to have preoperative PVT: odds ratio (OR)(1.36, 1.19, 1.78, 1.22 respectively). Patients with PSC, PBC, AIC, BMI ≤18, or with a preoperative PVT were more likely to have a postoperative VT: OR (1.93, 2.09, 1.64, 1.60, and 2.01, respectively). Despite the limited number of variables available in the UNOS database potentially related to thrombotic complications, this analysis demonstrates a clear association between autoimmune causes of ESLD and perioperative thrombotic complications. Perioperative management of patients at risk should include strategies to reduce the potential for these complications.