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.).
Condition: Nerve Block; Efficiency; Sciatic Nerve; Ultrasonography; Minimum Effective Dose
Study type: Interventional

Summary: 
      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.
    


Intervention name(s): Sciatic nerve block under ultrasound control with a electrostimulator peripheral nerves 12.5 ml 1% lidocaine; sciatic nerve blockade under ultrasound control without a peripheral nerve stimulator 12.5 ml 1% lidocaine
Intervention type(s): Procedure; Procedure
Intervention description(s): Following the ultrasound visualization of the femoral nerve, a insulated injection needle was connected to the nerve stimulator . Under ultrasound visualization guidance, the needle of the electronic nerve stimulator was positioned at the sciatic nerve (in plane) from its lateral side at a slightly superior position . A marker for LA introduction was the visualization of the needle end near the nerve, and a positive muscular response . Subsequently, the introduction of LA solution was initiated (12.5 ml 1% lidocaine).If LA was spreading from the lateral side down to the nerve, then the needle was replaced to the upper point of the nerve and the rest of LA was introduced, and vice versa . The presence of a complete and incomplete spread of LA along the entire circumference of the nerve was assessed. Correspondingly, if the anesthetic was spreading upwardly, the needle would be downwardly replaced.
In addition, a femoral nerve block is performed.; Under ultrasound visualization guidance, the needle owas positioned at the sciatic nerve (in plane) from its lateral side at a slightly superior position . A marker for LA introduction was the visualization of the needle end near the nerve. Subsequently, the introduction of LA solution was initiated. The position of the needle was corrected 1-2 times according to the type of anesthetic spread. If LA was spreading from the lateral side down to the nerve, then the needle was replaced to the upper point of the nerve and the rest of LA was introduced, and vice versa . The presence of a complete and incomplete spread of LA (12.5 ml 1% lidocaine) along the entire circumference of the nerve was assessed. Correspondingly, if the anesthetic was spreading upwardly, the needle would be downwardly replaced.
In addition, a femoral nerve block is performed.
Other intervention name(s): Anesthesia for lower limb surgery; Anesthesia for lower limb surgery
Intervention MeSH terms: Lidocaine; Anesthetics
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Other
Keywords: sciatic nerve block; ultrasound guidance; electrical stimulation of peripheral nerves; lidocaine; Аnesthetics Local; Minimum Effective Dose