Before going to the operating room, the patient must remove glasses, contact lenses, dentures and all jewelry. When the patient is admitted to the operating room, a blood pressure cuff is placed on his arm, ECG electrodes are attached to his chest to monitor his heart rate, and a clip (pulse oximeter) is placed on his finger to measure blood oxygen saturation. In this way, the anesthesiologist monitors the patient's vital functions on a monitor during anesthesia, which is called monitoring. The extent of monitoring depends on the type and complexity of the operation and the patient's associated diseases.

In addition to the usual basic monitoring described above, in certain operations or patients, we use extended monitoring (supervision): direct continuous measurement of blood pressure by inserting a plastic cannula into the artery, measuring the depth of anesthesia using a BIS (bispectral index) monitor by placing special electrodes on the patient's forehead, measuring urine volume (a urinary catheter is inserted before the operation), measuring brain tissue oxygenation (oxygen saturation) with an NIRS (near infrared spectroscopy) monitor, measuring temperature...; there are also a wide variety of technologically highly developed and accurate monitors that are used in demanding operations (LIDCO, PICCO...) to measure hemodynamic parameters, such as: cardiac output, pulmonary pressure.

During general anesthesia, respiratory parameters and lung function are also monitored on the anesthesia machine monitor for all patients: breathing rate and depth, % of oxygen in the breathing mixture, CO2 in exhaled air... The anesthesiologist or anesthesiology nurse is with the patient throughout the operation, carefully monitoring the aforementioned parameters and reacting immediately to the slightest deviations. In this way, the anesthesiologist individually adjusts the depth of anesthesia to the individual phases of the operation and the health condition of the individual patient.

Before each anesthesia, the anesthesiologist nurse inserts a plastic cannula into the patient's arm vein and sets up an infusion. Through this intravenous route, the patient is then given all the necessary substances and medications that he or she needs during and after the surgery: sleeping pills, medications to relieve pain and nausea, medications to regulate blood pressure and pulse, fluids, blood...