Objectives: To evaluate the analgesic effect of spinal anesthesia with a mixture of bupivacaine and morphine and its side effects in prepared subtotal hysterectomy. Subjects and method: A prospective observational study, analyzing on 50 patients with ASA 1-2, aged 18-60, without contraindication for spinal anesthesia, who had prepared subtotal hysterectomy at Thai Nguyen University of Medicine and Pharmacy Hospital. The patients were not taken premedication and indicated the needle at L2 - L3 slot, injected the mixture with the dose of bupivacaine 0.2 mg/kg + 0.1 mg morphine. Results: This method achieved good results. The analgesic latent duration at T10 was 3.26 +/- 0.47 minutes. The insensitive duration was 122.32 +/-:15.5 minutes. 100 percent of patients achieved a good level of analgesia for surgery. The pain-relief duration after the su'rgery was 23.06 +/- 0.8 hours. During the surgery, the patients who had nausea took up 2 percent, with shakes - 4 percent, and itchiness - 4 percent. After the surgery, there was no patient suffering from vomiting or nausea
those with itchiness accounted for 4 percent and with urinary retention - 2 percent.