Effects of propofol and sevoflurane on hepatic blood flow : a randomized controlled trial

Background Maintaining adequate perioperative hepatic blood flow (HBF) supply is essential for preservation of postoperative normal liver function. Propofol and sevoflurane affect arterial and portal HBF. Previous studies have suggested that propofol increases total HBF, primarily by increasing portal HBF, while sevoflurane has only minimal effect on total HBF. Primary objective was to compare the effect of propofol (group P) and sevoflurane (group S) on arterial, portal and total HBF and on the caval and portal vein pressure during major abdominal surgery. The study was performed in patients undergoing pancreaticoduodenectomy because - in contrast to hepatic surgical procedures - this is a standardized surgical procedure without potential anticipated severe hemodynamic disturbances, and it allows direct access to the hepatic blood vessels. Methods Patients were randomized according to the type of anesthetic drug used. For both groups, Bispectral Index (BIS) monitoring was used to monitor depth of anesthesia. All patients received goal-directed hemodynamic therapy (GDHT) guided by the transpulmonary thermodilution technique. Hemodynamic data were measured, recorded and guided by Pulsioflex (TM). Arterial, portal and total HBF were measured directly, using ultrasound transit time flow measurements (TTFM) and were related to hemodynamic variables. Results Eighteen patients were included. There was no significant difference between groups in arterial, portal and total HBF. As a result of the GDHT, pre-set hemodynamic targets were obtained in both groups, but MAP was significantly lower in group S (p = 0.01). In order to obtain these pre-set hemodynamic targets, group S necessitated a significantly higher need for vasopressor support (p < 0.01). Conclusion Hepatic blood flow was similar under a propofol-based and a sevoflurane-based anesthetic regimen. Related to the application of GDHT, pre-set hemodynamic goals were maintained in both groups, but sevoflurane-anaesthetized patients had a significantly higher need for vasopressor support

Predicting perioperative acute kidney injury in liver surgery

Introduction: During the perioperative period, acute kidney injury (AKI) is a serious complication with increased short- and long-term mortality (1, 2, 3). In former studies, the incidence of AKI following hepatobiliary surgery varied between 5.1 and 15.5% (10, 11, 13-15). The aim of the study is to examine the perioperative risk factors for development of AKI in patients undergoing liver surgery and to compare predictive models made by supervised decision tree models. Methods: In this retrospective cohort study, patients who had undergone liver surgery between March 2010 and December 2017 in Ghent University Hospital were screened after ethical committee approval. A set of preoperative and postoperative laboratory results, surgery and patient characteristics were collected. To create a predictive model, the dataset was randomly divided into a training set (60%) to train the model and a test set (40%) to analyze the accuracy of the model. To train the model, tree-based models were used in the form of a simple tree, pruned tree, bagging trees, random forests and boosting trees. Results: 1162 patients were analyzed and because of missing data, 602 patients had to be excluded from the dataset. The misclassification error of the different decision tree models varied between 3.12% and 4.02%. Random forests is the prediction model with the lowest misclassification error of 3.12%. The difference in serum creatinine immediately after surgery is ranked as the highest predictor with a relative influence of 50% in the boosting trees model. This predictor is followed by postoperative serum creatinine with a relative influence of 13%. At the third place is preoperative hemoglobin with a relative influence of 9.2%. Conclusion: Decision tree models can predict AKI after hepatobiliary surgery in this study. Of all the predictive models, random forests had the lowest misclassification rate and this model should be explored more often in future research trials

How sensitive and specific are MRI features of sacroiliitis for diagnosis of spondyloarthritis in patients with inflammatory back pain?

Objective: To determine the sensitivity and specificity of MRI features of sacroiliitis in spondyloarthritis (SpA). Materials and methods: A retrospective study reviewed MRI of the sacroiliac (SI) joints in 517 patients with inflammatory back pain. Sensitivity, specificity, positive and negative likelihood ratios of active and structural lesions of sacroiliitis with final clinical diagnosis as golden standard was calculated. Results: MRI showed active inflammation in 42% of patients (bone marrow oedema (BMO) (41.5%), capsulitis (3.3%), enthesitis (2.5%)) and structural changes in 48.8% of patients (erosion (25%), fat infiltration (31.6%), sclerosis (32%) and ankylosis (7.6%)). BMO was the MRI feature with the highest sensitivity (65.1%) for diagnosis of SpA. Capsulitis (99%), enthesitis (98.4%), ankylosis (97.4%) and erosion (94.8%) had a high specificity for diagnosis of SPA, whereas BMO (74.3%), sclerosis (75.8%) and fat infiltration (84.0%) were less specific. BMO concomitant with enthesitis, capsulitis or erosions increased the specificity. Concomitant presence of BMO and sclerosis or fat infiltration decreased the specificity. Conclusion: BMO is moderately sensitive and specific for diagnosis of SpA in patients with inflammatory back pain. BMO concomitant with enthesitis, capsulitis, ankylosis or erosion increases the specificity. Concomitant fat infiltration or sclerosis decreases the specificity for diagnosis of SpA. Of all lesions, erosion had by far the highest positive likelihood ratio for diagnosis of SpA