ASA classification and interobserver agreement among veterinarians and graduate students in Brazil

Abstract

ASA classification is a widespread system used for assessing physical status in surgical patients. However, studies have shown weak interobserver agreement in human and in a smaller scale in animals. This study’s goal was investigating this system’s usage profile and interobserver agreement among veterinarians and graduate students through an online survey containing demographic and professional qualification questions and five clinical cases. Ninety-four participants representing thirteen states (predominantly RJ and SP) responded the questionnaire, amongst 48.9% were veterinarians graduated in 26 different institutions – majorly general clinicians – and 51.1% were graduate students from 48 different institutions. There were 79.8% female and 20.2% male respondents and there was no difference in gender distribution between veterinarians and students. Among veterinarians (67.4% graduates and 32.6% postgraduates), 76.1% reported using ASA classification “always” or “sometimes” although only 19.6% reported working directly in anesthesia which shows a broad usage of this system. Almost every participant reported having learned the ASA classification in graduate course (93.5% of the veterinarians and 89.5% of students). There were no significant correlations between “study degree” and “time from graduation” and ASA status usage however veterinary anesthetists reported using it more frequently (P < 0.0001). No difference was shown in ASA status attributed by veterinarians and students for each of the presented cases: A (P = 0,263), B (P = 0.121), C (P = 0.443), D (P = 0.939) and E (P = 0.849), although there was weak interobserver agreement among veterinarians (Fleiss k = 0.365, P < 0.0001) and students (Fleiss k = 0.363, P < 0.0001). All five clinical cases were classified in at least three different ASA classes by veterinarians and four of them were classified in at least four different ASA classes by students, showing high dispersion. This study showed weak interobserver agreement in ASA classification among veterinarians and among students besides showing a widespread usage of this physical status classification system.