National Register of Postoperative Outcomes in the Russian Federation: a Multicenter Observational Study

Currently, the incidence of perioperative complications and mortality associated with surgical intervention are minimized. However, taking into account the significant number of surgical interventions performed worldwide (more than 300 million per year), the total number of patients with complicated postoperative periods is large, and postoperative mortality ranks third in the structure of causes of death (7, 7%), second only to coronary heart disease and stroke. Moreover, even in discharged patients, complications that develop can significantly reduce quality of life and worsen long-term prognosis. To a greater extent, the above applies to high-risk patients, whose identification is a priority task of anesthesiology.

Identification of risk factors that cause a high probability of an unfavorable outcome is currently unthinkable without conducting comprehensive prospective population-based studies, which, on the one hand, make it possible to assess the contribution of many variables to the risk of complications and mortality, and on the other hand, to maximally cover a certain population by identifying characteristic predictors for it. To date, several population-based studies and programs have been described in the literature that have led to the creation of national databases (registries) of postoperative outcomes. Such studies include several international (ISOS, EuSOS and ASOS) and national ones, such as SweSOS [8] or ColSOS , which are at different stages of implementation. Among the national databases, the best known is the ACS-NSQIP (American College of Surgeons National Surgical Quality Improvement Program) database, which contains information on the outcomes of surgical treatment for more than 5 million patients in the United States since 1991 .

The results obtained from these studies often vary widely, due to the diversity of approaches to study inclusion criteria, differences in the characteristics of the populations studied, and the lack of a uniform view on the classification of postoperative outcomes. When assessing mortality, the authors most often record 30-day mortality, however, taking into account modern ideas about the role of perioperative factors and complications in the development of an unfavorable long-term outcome, the need to determine one-year mortality becomes obvious. As shown by the national observational study SweSOS, the mortality rate increases significantly over time, with 30-day mortality being 1.8%, 3-month mortality - 3.9%, and 6-month and annual mortality - 5.0% and 8.5% , respectively .

There is also no uniform approach to the registration of postoperative complications, and modern protocols use several systems, the most common of which are the classification of the joint working group of ESA (The European Society of Anesthesiologists) and ESICM (The European Society of Intensive Care Medicine, The European). Society of Intensive Care Medicine) and the ACS-NSQIP classification (The American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP)). And although they are similar in many ways (complications are grouped into blocks according to the nature of the disorders), differences are also present, and even the same complication may have a different definition. In addition, some significant outcomes are not included in these classifications, which predetermines their underestimation.

Of course, one of the advantages of creating a large population-based database is the recording of a large number of potential predictors of adverse outcome and subsequent assessment of their individual contribution to the complex perioperative risk. The type of surgical intervention itself is a factor that largely determines the likelihood of complications.