Pierre A. Clavien

In Brief Background and Aims: The lack of consensus on how to define and grade adverse postoperative events has greatly hampered the evaluation of surgical procedures. A new classification of complications, initiated in 1992, was updated 5 years ago. It is based on the type of therapy needed to correct the complication. The principle of the classification was to be simple, reproducible, flexible, and applicable irrespective of the cultural background. The aim of the current study was to critically evaluate this classification from the perspective of its use in the literature, by assessing interobserver variability in grading complex complication scenarios and to correlate the classification grades with patients', nurses', and doctors’ perception. Material and Methods: Reports from the literature using the classification system were systematically analyzed. Next, 11 scenarios illustrating difficult cases were prepared to develop a consensus on how to rank the various complications. Third, 7 centers from different continents, having routinely used the classification, independently assessed the 11 scenarios. An agreement analysis was performed to test the accuracy and reliability of the classification. Finally, the perception of the severity was tested in patients, nurses, and physicians by presenting 30 scenarios, each illustrating a specific grade of complication. Results: We noted a dramatic increase in the use of the classification in many fields of surgery. About half of the studies used the contracted form, whereas the rest used the full range of grading. Two-thirds of the publications avoided subjective terms such as minor or major complications. The study of 11 difficult cases among various centers revealed a high degree of agreement in identifying and ranking complications (89% agreement), and enabled a better definition of unclear situations. Each grade of complications significantly correlated with the perception by patients, nurses, and physicians (P < 0.05, Kruskal-Wallis test). Conclusions: This 5-year evaluation provides strong evidence that the classification is valid and applicable worldwide in many fields of surgery. No modification in the general principle of classification is warranted in view of the use in ongoing publications and trials. Subjective, inaccurate, or confusing terms such as “minor or major” should be removed from the surgical literature. A critical appraisal 5 years after introducing a new system to rank postoperative complications has shown a rapid and wide acceptance in the literature. To further support the use of this system, we documented an excellent correlation between the various grades of severity and perception by patients and health care providers, and obtained consensus among experts to rank difficult cases. The grades are sufficiently self explanatory that subjective terms such as minor and major complications should be avoided.

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.

BACKGROUND: Cold ischemia/warm reperfusion (CI/WR) liver injury remains a problem in liver transplants. Sinusoidal endothelial cells (SEC) are a target of CI/WR injury, during which they undergo apoptosis. Because caspase proteases have been implicated in apoptosis, our aim was to determine whether liver CI/WR injury induces a caspase-dependent apoptosis of SEC. METHODS: Rat livers were stored in the University of Wisconsin (UW) solution for 24 hr at 4 degrees C and reperfused for 1 hr at 37 degrees C in vitro. Apoptosis was quantitated using the TUNEL assay, and caspase 3 activation determined by immunohistochemical analysis. Rat liver orthotopic liver transplants (OLT) were also performed using livers stored for 30 hr. RESULTS: Terminal deoxynucleotide transferase-mediated dUTP nick end labeling (TUNEL) positive hepatocytes were rare and did not increase during CI/WR injury. In contrast, TUNEL positive SEC increased 6-fold after reperfusion of livers stored under cold ischemic conditions, compared with controls or livers stored but not reperfused. Immunohistochemical analysis demonstrated active caspase 3 only in endothelial cells after CI/WR injury. When IDN-1965, a caspase inhibitor, was given i.v. to the donor animal and added to UW solution and the reperfusion media, TUNEL positive endothelial cells were reduced 63+/-11% (P<0.05). Similarly, the duration of survival after OLT was significantly increased in the presence of the inhibitor. CONCLUSION: During liver CI/WR injury: 1) selective apoptosis of endothelial cells occurs; 2) caspase 3 is activated only in endothelial cells; and 3) a caspase inhibitor reduces endothelial cell apoptosis and prolongs animal survival after OLT. The pharmacologic use of caspase inhibitors could prove useful in clinical transplantation.