Before the procedure an oral premedication is given. After admission to the operating room, intravenous access is established and the patient receives a drip infusion of 500 ml 0.9% Natrium Chloratum with an antibiotic (2nd generation cephalosporin). Constant monitoring is ensured of ECG, heart rate, and pulse oxymetry. Non-invasive blood pressure measurement is taken every five minutes. To maintain patients' blood oxygenation, oxygen is delivered with the use of a facemask. Spinal anesthesia is performed with patients in the sitting position, most frequently in the L3 L4 space (in the case of technical difficulties - L2 L3 or L4 L5) using 8-15 mg 0.5% hyperbaric bupivacaine depending on the patient's anthropometric parameters. The needles used are 25-27G pencil point. After drug administration, the patient is placed in the supine position.