Unilateral hypobaric spinal anesthesia is an anesthetic technique that provides hemodynamic stability, indicated for subumbilical surgery, especially in elderly subjects. The aim of this work was to demonstrate the effectiveness of this technique, which is very commonly practiced at the reference hospital in Maradi, through a descriptive and cross-sectional retrospective study over three years. Only patients who underwent surgery and had a complete file were included. A total of 56 patients were included, with a female predominance and a mean age of 78.03±5.4 years. The age group [60-70 years] represents 50%. The types of surgeries performed were traumatic and vascular. Surgical indications were dominated by pelvic limb trauma in 60.71% of cases. More than half of our patients (57.14%) had at least one comorbidity, with diabetes and hypertension at the forefront, accounting for 40.66% and 37.51%, respectively. At admission, patients presented a diverse hemodynamic state. Indeed, 10 had hypotension and 7 had hypertension. Bupivacaine was the only local anesthetic administered. Fentanyl and clonidine were the associated adjuvants. Osteosynthesis was the main surgical indication followed by amputation with respective rates of 51.78% and 28.57%. After anesthesia, patients were positioned in the lateral decubitus position, with the limb to be operated on positioned above, for 15 minutes. After this period, a failure rate of 8.20% was observed. Conversely, success was noted in 51 patients, 11 of whom had received a blood transfusion for intraoperative bleeding. However, no use of vasopressors was reported. The average duration of surgery was 64±11 minutes. No major incidents or conversions were reported intraoperatively. The average stay in the post-anesthesia recovery room was 43±12 minutes. The average anesthesia duration was 87±13 minutes. No incidents were reported postoperatively. This study allowed us to highlight the contribution of hypobaric unilateral spinal anes