Actuality: Frailty is a geriatric syndrome characterized by an age-associated decrease in the physiological reserve and functions of many body systems, leading to an increased vulnerability of the elderly organism to the effects of endo- and exogenous factors, with a high risk of adverse outcomes for health, loss of autonomy and death [1]. Purpose: To develop ways to optimize the preoperative preparation of patients with senile asthenia in order to prevent postoperative delirium and evaluate their effectiveness. Material and methods: 279 people: control group - standard management, 133 patients aged 66 to 86 years (average age 71.4 + 1.2 years, men - 74 people, women - 59 people); the studied group - management according to the algorithm, 146 elderly patients aged 65 to 84 years (average age 72.8 + 2.6 years, men - 79 people, women - 67 people). Results: we analyzed the effectiveness of the algorithm we proposed, it turned out that postoperative delirium developed in 38.4 + 0.5 cases in the control group patients, in patients of the study group - 4.3 + 0.01, 8.9 times less often when applying the algorithm for preparing elderly and senile patients with asthenia syndrome for planned surgical interventions on the abdominal organs (χ2 = 0.95, p = 0.6578, which indicated statistically significant differences in the results). Attention was also drawn to the fact that the duration of postoperative delirium was 38.1 + 3.2 hours in patients of the control group, and 11.2 + 1.4 hours (p