Evaluation of block success with perfusion index measurement femoral and sciatic nerve block in patients with lower extremity surgery

Objective: Peripheral nerve block methods are now being used increasingly in extremity surgery. However, the traditional methods used to assess the success and adequacy of a block depend on time-consuming, subjective, and patient collaboration. Therefore, the search for an objective method to assess the success and adequacy of the block continues. In this study, we aimed to investigate whether the Perfusion Index (PI) measured by pulse oximetry technology is an early and quantitative marker for the evaluation of the success of combined femoral sciatic block. Method: Elective lower extremity surgery due to combined administration femoral sciatic block, between 18-65 years, ASA I-III, 80 patients were included. All patients; 30 ml 0.25% bupivacaine + 1% lidocaine solution for the sciatic block, 20 ml 0.25% bupivacaine + 1% lidocaine solution for the femoral block was applied with ultrasonography and nerve stimulator. Heart rate, mean arterial pressure, peripheral oxygen saturation, perfusion index, capillary filling time and distal skin temperature were measured at 0, 5, 10, 20, 30 minutes. Cold sensory loss test, motor force test and pin prick test were recorded. Results: In our study, when the mean PI between the lower extremity and the contralateral lower extremity were examined; At the 5, 10, 20 and 30 minutes, the mean PI averages were significantly higher (p <0.05). Cold sense loss time; 16,58 ± 7,94 min, starting time of the motor block; 12,60 ± 5,65 min, Pin-prick test positive time; 15,34 ± 6,19 min. Conclusion: It was concluded that PI is an objective, rapid, practical and non-invasive method that can be used to evaluate the success of combined femoral sciatic block. Keywords: Peripheral nerve block, Combined femoral sciatic block, Perfusion index, Increased perfusion.