Evaluation of spinal anesthesia efficiency with pleth variability index and perfusion index

Introduction and Objective: Nowadays, spinal block is applied in most lower abdominal, perineum and lower extremity surgeries, considering the patients request. Perfusion index is a measure shown in many pulse oximeters. In this study; it was aimed to evaluate patients undergoing elective or emergency surgeries in the main building operating room of Dicle University Hospitals and who underwent spinal block in terms of predicting the success of the block by measuring pleth variability index (PVI) and perfusion index (PI) with a bedside pulse oximeter device. Materials and Methods: Patients undergoing lower abdominal, perineum and lower extremity surgery, scheduled for emergency or elective surgery, and undergoing spinal anesthesia were included in this study. 53 male and female patients with ASA I-II and between the ages of 18-65 were included in the study. In addition to standard anesthesia monitoring, all patients were monitored with a pulse oximeter device for PVI and PI measurements with spectrophotometric method. Hemodynamic parameters, PVI and PI values of the patients were recorded at baseline and at the 1st, 3rd, 5th, 10th and 20th minutes. At the same time, the dermatome area without pain with the pinprick test was recorded as the level of sensory block. In addition, motor strength was evaluated with the Modified Bromage Scale in the lower extremities at the same time. Results: Looking at the average PI in the finger and toe; basal values in the toe were found to be significantly lower (p <0.05), while the PI averages at the 3rd, 5th, 10th and 20th minutes were significantly higher (p <0.05) and the difference at the 1st minute was not significant (p> 0.05). Comparing the average PI measured from the toe at different times; the difference between the baseline value and the 1st, 3rd, 5th, 10th, and 20th minutes was found to be significant (p <0.05). No significant correlation was found between the MAP and PI and PVI averages obtained from the toes of the patients at the 1st, 3rd, 5th, 10th and 20th minutes. Conclusion: As a result, we found that the PI values measured from the toe after spinal block started to increase significantly from the first minute compared to the basal values. We concluded that measurement of Pİ is valuable and useful in early, easy and objective evaluation of spinal block success. Keywords: Spinal anesthesia, pleth variability index, perfusion index