Objective: to analyze the optimal number of days of active drainage after total thyroidectomy Data sources and methods: a longitudinal cohort study was conducted that followed the process of preparing 65 for the duration of 19.07.2023. to 19.01.2024. patients for total thyroidectomy and their postoperative course with special reference to the drain and drainage content. Descriptive statistical methods were used to describe the frequency distribution of the investigated variables; the Kolmogorov-Smirnov test was used to test the normality of the distribution; homoscedasticity was tested by Levene's homogeneity of variance test; to check the differences in the amount of aspirate between several independent groups of subjects (according to the pathohistological findings), one-way analysis of variance with post hoc Tukey test was used. The Chi square test (χ2 test) was used to examine differences in the distribution of categorical variables (gender and pathohistological findings). Non-parametric correlations (Spearman's) were used to examine the relationship between age and body weight with the amount of aspirate. The level of statistical significance was P < 0.05. The statistical packages IBM SPSS Statistics for Windows, version 25 (IBM Corp., Armonk, NY, USA; 2017) and JASP, version 0.17.2.1 (Department of Psychological Methods, University of Amsterdam, Amsterdam, The Netherlands) were used for processing. Results: Based on the research results, the optimal number of days for the application of active drainage after total thyroidectomy can be considered 2 days. Data analysis revealed that the amount of aspirate is significantly higher on the first day, while the amount of aspirate decreases on the second and third day of drainage. Significant differences in the amount of aspirate between the first and second days, and between the second and third day, indicate that most of the fluid is removed already in the first 24 hours. Also, the results of the research showed that older age, higher body weight and male sex of the patient are associated with larger amounts of aspirate. Conclusion: The hypothesis of this thesis has been confirmed and defended. Considering that the differences in the amount of aspirates decrease after the first day and that there are no significant differences in the total amount of aspirates between the second and the third day, it can be concluded that reducing the duration of active drainage to 2 days could be sufficient for effective management of postoperative effusion and reduction of possible complications.