ESRA19-0534 Sciatic nerve block combined with femoral nerve block in postoperative pain management after total knee arthroplasty with megaendoprosthesis in two patients with osteosarcoma

Background and aims Total knee arthroplasty (TKA) is associated with severe postoperative pain. Parenteral opioids are increasingly replaced by peripheral nerve blocks (PNBs) and periarticular injections in postoperative pain management. Methods 15-year-old male, BMI 19, with osteosarcoma in left distal femur scheduled for tumour resection and TKA refused the proposed continuous neuroaxial anaesthesia. The patient opted for general anaesthesia with PNB for postoperative pain control. 21-year-old female, BMI 17, with left distal femur osteosarcoma and solitary pulmonary metastasis agreed to spinal anaesthesia with intravenous sedation and PNBs for pain control. Ultrasound guided femoral catheter placement for intermittent femoral nerve block with bolus of levobupivacain 0.25% 15 mL was followed in both patients by sciatic nerve block guided by peripheral nerve stimulator, with 10 mL of 0.5% levobupivacain, in PACU, after the surgical procedure. Results In both cases the patient was sent to the ward with VAS 2, both received boluses via femoral catheter 8 hourly. Early physiotherapy started 24 hours after the surgery. 48 hours postoperatively both patients had VAS 2. Femoral catheters were removed. In addition to local anaesthetic via femoral catheter the general anaesthesia patient received altogether one dose of opioid and two doses of NSAIR in the whole postoperative period, while the spinal anaesthesia patient received NSAIR until day 3. Conclusions Regional techniques provide powerful analgesia with minimal risk and few adverse effects. The technique combining intermittent femoral with sciatic nerve block proved to be adequate for postoperative pain control after major knee surgery in our two patients.