Ksenija Slankamenac

The Comprehensive Complication Index: A Novel Continuous Scale to Measure Surgical Morbidity.

Objective:To develop and validate a comprehensive complication index (CCI) that integrates all events with their respective severity. Background:Reporting of surgical complications is inconsistent and often incomplete. Most studies fail to provide information about the severity of complications, or inform only on the most severe event, ignoring events of lesser severity. Methods:We used an established classification of complications, adopting methods from operation risk index analysis in marketing research to develop a formula that considers all complications that may occur in a patient. The weights of each grade of complication, defined as median reference values, were obtained from 472 participants, who rated 30 different complications. Validation to assess sensitivity to treatment effects and validity of the CCI was performed by 4 different approaches, based on 1299 patients. Results:The CCI is calculated as the sum of all complications that are weighted for their severity (multiplication of the median reference values from patients and physicians). The final formula yields a continuous scale to rank the severity of any combination of complications from 0 to 100 in a single patient. The CCI was highly sensitive in detecting treatment effect differences in the context of a randomized trial (effect size detected by CCI vs conventional standardized morbidity outcomes). It also showed a negative correlation with postoperative health status (r = −0.24, P = 0.002), and high correlation with the results of patient-rated single and multiple complications on conjoint analysis (r = 0.94, P < 0.001). Conclusions:The CCI summarizes all postoperative complications and is more sensitive than existing morbidity endpoints. It may serve as a standardized and widely applicable primary endpoint in surgical trials and other interventional fields of medicine. The CCI can be readily computed on the basis of tabulated complications according to the Clavien-Dindo classification (available at www.assessurgery.com).

Assessment of hepatic steatosis by expert pathologists: the end of a gold standard

Background:The presence of fat in the liver is considered a major risk for postoperative complication after liver surgery and transplantation. The current standard of quantification of hepatic steatosis is microscopic evaluation by pathologists, although consistency in such assessment remains unclear. Computerized image analysis is an alternative method for objective assessment of the degree of hepatic steatosis. Methods:High resolution images of hematoxylin and eosin stained liver sections from 46 consecutive patients, initially diagnosed with liver steatosis, were blindly assessed by 4 established expert pathologists from different institutions. Computerized analysis was carried out simultaneously on the same sections. Interobserver agreement and correlation between the pathologists’ and computerized assessment were evaluated using intraclass correlation coefficients (ICC), Spearman rank correlation coefficients, or descriptive statistics. Results:Poor agreement among pathologists (ICC: 0.57) was found regarding the assessment of total steatosis, (ICC >0.7 indicates acceptable agreement). Pathologists’ estimation of micro- and macrosteatosis disclosed also poor correlation (ICC: 0.22, 0.55, respectively). Inconsistent assessment of histological features of steatohepatitis (lobular inflammation, portal inflammation, hepatocyte ballooning, and Mallory hyaline) was documented. Poor conformity was also shown between the computerized quantification and ratings of 3 pathologists (Spearman rank correlation coefficients: 0.22, 0.82, 0.28, and 0.38). Conclusion:Quantification of hepatic steatosis in histological sections is strongly observer-dependent, not reproducible, and does not correlate with the computerized estimation. Current standards of assessment, previously published data and the clinical relevance of hepatic steatosis for liver surgery and transplantation must be challenged.

The Impact of Complications on Costs of Major Surgical Procedures: A Cost Analysis of 1200 Patients

Objective:To assess the impact of postoperative complications on full in-hospital costs per case. Background:Rising expenses for complex medical procedures combined with constrained resources represent a major challenge. The severity of postoperative complications reflects surgical outcomes. The magnitude of the cost created by negative outcomes is unclear. Patients and MethodsMorbidity of 1200 consecutive patients undergoing major surgery from 2005 to 2008 in a tertiary, high-volume center was assessed by a validated, complication score system. Full in-hospital costs were collected for each patient. Statistical analysis was performed using a multivariate linear regression model adjusted for potential confounders. Results:This study population included 393 complex liver/bile duct surgeries, 110 major pancreas operations, 389 colon resections, and 308 Roux-en-Y gastric bypasses. The overall 30-day mortality rate was 1.8%, whereas morbidity was 53.8%. Patients with an uneventful course had mean costs per case of US

Are There Better Guidelines for Allocation in Liver Transplantation? A Novel Score Targeting Justice and Utility in the Model for End-Stage Liver Disease Era

27,946 (SD US

Relationship of individual scapular anatomy and degenerative rotator cuff tears

15,106). Costs increased dramatically with the severity of postoperative complications and reached the mean costs of US

Novel and simple preoperative score predicting complications after liver resection in noncirrhotic patients.

159,345 (SD US

The comprehensive complication index: a novel and more sensitive endpoint for assessing outcome and reducing sample size in randomized controlled trials

151,191) for grade IV complications. This increase in costs, up to 5 times the cost of a similar operation without complications, was observed for all types of investigated procedures, although the magnitude of the increase varied, with the highest costs in patients undergoing pancreas surgery. Conclusion:This study demonstrates the dramatic impact of postoperative complications on full in-hospital costs per case and that complications are the strongest indicator of costs. Furthermore, the study highlights a relevant savings capacity for major surgical procedures, and supports all efforts to lower negative events in the postoperative course.

The use of fatty liver grafts in modern allocation systems: risk assessment by the balance of risk (BAR) score.

Objectives:To design a new score on risk assessment for orthotopic liver transplantation (OLT) based on both donor and recipient parameters. Background:The balance of waiting list mortality and posttransplant outcome remains a difficult task in the era of the model for end-stage liver disease (MELD). Methods:Using the United Network for Organ Sharing database, a risk analysis was performed in adult recipients of OLT in the United States of America between 2002 and 2010 (n = 37,255). Living donor-, partial-, or combined-, and donation after cardiac death liver transplants were excluded. Next, a risk score was calculated (balance of risk score, BAR score) on the basis of logistic regression factors, and validated using our own OLT database (n = 233). Finally, the new score was compared with other prediction systems including donor risk index, survival outcome following liver transplantation, donor-age combined with MELD, and MELD score alone. Results:Six strongest predictors of posttransplant survival were identified: recipient MELD score, cold ischemia time, recipient age, donor age, previous OLT, and life support dependence prior to transplant. The new balance of risk score stratified recipients best in terms of patient survival in the United Network for Organ Sharing data, as in our European population. Conclusions:The BAR system provides a new, simple and reliable tool to detect unfavorable combinations of donor and recipient factors, and is readily available before decision making of accepting or not an organ for a specific recipient. This score may offer great potential for better justice and utility, as it revealed to be superior to recent developed other prediction scores.

Development and Validation of a Prediction Score for Postoperative Acute Renal Failure Following Liver Resection

BACKGROUND The etiology of rotator cuff disease is age related, as documented by prevalence data. Despite conflicting results, growing evidence suggests that distinct scapular morphologies may accelerate the underlying degenerative process. The purpose of the present study was to evaluate the predictive power of 5 commonly used radiologic parameters of scapular morphology to discriminate between patients with intact rotator cuff tendons and those with torn rotator cuff tendons. METHODS A pre hoc power analysis was performed to determine the sample size. Two independent readers measured the acromion index, lateral acromion angle, and critical shoulder angle on standardized anteroposterior radiographs. In addition, the acromial morphology according to Bigliani and the acromial slope were determined on true outlet views. Measurements were performed in 51 consecutive patients with documented degenerative rotator cuff tears and in an age- and sex-matched control group of 51 patients with intact rotator cuff tendons. Receiver operating characteristic analyses were performed to determine cutoff values and to assess the sensitivity and specificity of each parameter. RESULTS Patients with degenerative rotator cuff tears demonstrated significantly higher acromion indices, smaller lateral acromion angles, and larger critical shoulder angles than patients with intact rotator cuffs. However, no difference was found between the acromial morphology according to Bigliani and the acromial slope. With an area under the receiver operating characteristic curve of 0.855 and an odds ratio of 10.8, the critical shoulder angle represented the strongest predictor for the presence of a rotator cuff tear. CONCLUSION The acromion index, lateral acromion angle, and critical shoulder angle accurately predict the presence of degenerative rotator cuff tears.

Defining Benchmarks for Major Liver Surgery: A multicenter Analysis of 5202 Living Liver Donors.

Objective:To develop and validate a simple score to predict postoperative complications by severity after liver resection, using readily available preoperative risk factors. Background:Although liver surgery has enjoyed major development with dramatic reduction in mortality rates, the incidence of serious yet nonlethal complications remains high. No scoring system is currently available to identify those patients at higher risk for a complicated course. Methods:Complications were prospectively assessed in 615 consecutive noncirrhotic patients undergoing liver resection at the same institution. In randomly selected 60% of the population, multivariate-logistic-regression analysis was used to develop a score to predict severe complications defined as complications grades III, IV, and mortality (grade V) (Clavien-Dindo classification). The score was validated by calibration within the remaining 40% of the patients. Results:Grades III to V complications occurred in 159 (26%) of the 615 patients after liver resection, 90 (15%) were grade III, 48 (8%) grade IV, and 21 (3%) grade V. Four preoperative parameters were identified as independent predictors including American Society of Anesthesiologists category, transaminases levels (aspartate aminotransferase), extent of liver resection (>3 vs <3 segments), and the need for an additional hepaticojejunostomy or colon resection. A prediction score was calculated on the basis of 60% of the population (369 patients) using the 4 independent predictors ranging from 0 to 10 points. The risk to develop serious postoperative complications was 16% in “low risk” patients (0–2 points), 37% in “intermediate risk” patients (3–5 points) and 60% in “high risk” patients (6–10 points). The predicted mean for absolute risk for grades III to V complications was 27% in the validation population including 40% of the patients (n = 246), whereas the observed risk was 24%. Predicted and observed risks were similar throughout the different risk categories (P = 0.8). The score was significantly associated with hospital and intensive care unit stays. Costs of the entire procedure doubled among the 3 risk groups. Conclusions:This novel and simple score accurately predicts postoperative complications and cost in patients undergoing liver resection. This score allows early identification of patients at risk and may impact not only decision making for surgical intervention but also quality assessment and reimbursement.