Sciatic Nerve Blockade by Subgluteal Access 12.5 ml of 1% Lidocaine: US Guidance Versus US Guidance With Electrical Stimulation of Peripheral Nerves (Influence of the Sciatic Nerve Blockade on the Effectiveness of Small Doses of Local Anesthetic.).

Sciatic Nerve Blockade by Subgluteal Access 12.5 ml of 1% Lidocaine: US Guidance Versus US Guidance With Electrical Stimulation of Peripheral Nerves (Influence of the Sciatic Nerve Blockade on the Effectiveness of Small Doses of Local Anesthetic.).

In modern anesthesiology, peripheral nerve blocks are performed using ultrasound control and electrical stimulation of peripheral nerves (PEN), or only ultrasound control or only EPN. The most effective methods are with the use of ultrasound control. Until now, the effectiveness of the sciatic nerve blockade by the subgluteal approach, performed only under ultrasound control without EPN, in comparison with the blockade of the sciatic nerve performed under ultrasound control with EPN, has not been established.

There is no data on how the effectiveness of the blockade of the sciatic nerve with small doses of lidocaine is influenced by the method of performing the blockade: under ultrasound control versus ultrasound control with electrostimulation of the nerve.

Research hypothesis: the blockade of the sciatic nerve by the subgluteal approach (12.5 ml 1%lidocaine -Minimum Effective Dose - previously established ) performed only under ultrasound control has the same effectiveness as the blockade performed under the ultrasound control with EPN.

Inclusion Criteria:

• indication requiring anesthesia maintenance;
• patient's written consent about the type of anesthesia and possible complications of regional anesthesia

Exclusion Criteria:

• patient's refusal of application for the proposed form of anesthesia;
• patients younger than 18 years;
• patients weighing less than 50 kg;
• a physical status score of more than 3 determined by the American Society of Anesthesiologists (ASA);
• a history of allergic reactions to the drugs used;
• coagulopathies;
• infections of the skin at the injection site;
• neurological or neuromuscular diseases;
• severe liver diseases or kidney failures;
• an inability to cooperate with the patient.