American Society of Anesthesiologists Score: still useful after 60 years? Results of the EuSOS Study

Abstract

ObjectiveThe European Surgical Outcomes Study described mortality following in-patient surgery. Several factors were identified that were able to predict poor outcomes in a multivariate analysis. These included age, procedure urgency, severity and type and the American Association of Anaesthesia score. This study describes in greater detail the relationship between the American Association of Anaesthesia score and postoperative mortality.MethodsPatients in this 7-day cohort study were enrolled in April 2011. Consecutive patients aged 16 years and older undergoing inpatient non-cardiac surgery with a recorded American Association of Anaesthesia score in 498 hospitals across 28 European nations were included and followed up for a maximum of 60 days. The primary endpoint was in-hospital mortality. Decision tree analysis with the CHAID (SPSS) system was used to delineate nodes associated with mortality.ResultsThe study enrolled 46,539 patients. Due to missing values, 873 patients were excluded, resulting in the analysis of 45,666 patients. Increasing American Association of Anaesthesia scores were associated with increased admission rates to intensive care and higher mortality rates. Despite a progressive relationship with mortality, discrimination was poor, with an area under the ROC curve of 0.658 (95% CI 0.642 - 0.6775). Using regression trees (CHAID), we identified four discrete American Association of Anaesthesia nodes associated with mortality, with American Association of Anaesthesia 1 and American Association of Anaesthesia 2 compressed into the same node.ConclusionThe American Association of Anaesthesia score can be used to determine higher risk groups of surgical patients, but clinicians cannot use the score to discriminate between grades 1 and 2. Overall, the discriminatory power of the model was less than acceptable for widespread use.

Systematic review of the use of big data to improve surgery in low- and middle-income countries

“…). Following assessment, 68 articles, involving 708 032 patients across 71 LMICs, were included in the review ( Tables S1 and S2 , supporting information). Country‐specific patient numbers were reported in 60 studies but were absent from six and two provided total LMIC patient numbers only.…”

“…The largest cohort of patients originated from the DATASUS registry in Brazil (428 346 patients), which explored outcomes after hysterectomy. Five multinational observational cohort studies were performed in the past 5 years, with the majority conducted over 7 days.…”

“…a Number of studies and b number of patients in studies of LMICs. Countries with fewer than 100 patients recruited for a multinational study were excluded from a , as were studies in which LMIC‐specific patient numbers were not specified…”

Categorical measurements of subjectiveness: is there still a role for the ASA classification?

“…This brings us to ask what we should currently expect from the ASA score. Moreno et al., ( 13 ) in this edition, used data from the EuSOS study to further evaluate the role of the ASA score in modern practice. It was a very timely analysis for which the authors should be commended.…”

“…( 15 ) Moreno’s work highlights the importance of keeping a high level of suspicion regarding the validity of old practices. ( 13 ) It may not be sufficient to deconstruct the role of a very old tool, but this is a move forward in the interpretation of the ASA score.…”