Objective. To determine the effectiveness of the use of small doses and volumes of local anesthetics for nerve block anaesthesia, as a component of combined anesthesia for orthopedic and traumatological operations on the lower extremities in children.

Materials and methods. The study comprised 36 children aged 7 to 17 years who underwent elective orthopedic and traumatologic surgery on the lower extremities. The patients were divided into two groups. Patients from the 1st group underwent combined general and nerve block anesthesia with a combination of lidocaine 1 % and ropivacaine 0,75 % in a 1:1 ratio with standard doses of local anesthetics; Patients from the 2nd group underwent combined general and conduction anesthesia with a combination of 1 % lidocaine and 0,5 % ropivacaine in a 1:1 ratio with small doses of local anesthetics. The effectiveness of anesthesia and the duration of postoperative pain relief was assessed in both groups.

Results. The study found that both combinations of local anesthetics were effective. The dosage of lidocaine in children from the 1st group was 2,1 [1,95; 2,5] mg/kg, and from the 2nd group 1,45 [1,25; 1,75] mg/kg, and the dosage ropivacaine in patients in the 1st group was 1,6 [1,45; 1,9] mg/kg, and in the 2nd group — 0,74 [0,63; 0,86] mg/kg, respectively. The volume of local anesthetic used for blockade of the sciatic nerve in the 1st group was 0,28 [0,25; 0,33] ml/kg, in the 2nd group it was 0,19 [0,14; 0,23] ml/kg . The volume of local anesthetic for blockade of the femoral nerve in the 1st group was 0,15 [0,13; 0,2] ml/kg, and in the 2nd group it was 0,11 [0,1; 0,12] ml/kg. There were no significant complications and adverse outcomes associated with anesthesia.

Conclusion. Combined general and nerve block anesthesia with small doses and volumes of local anesthetics provides effective and safe pain relief during orthopedic and traumatological operations on the lower extremities in children and reduces the risk of systemic toxicity.