The effects of intraoperative fluid management on hemodynamics and tissue oxygenation according to PVİ (Pleth variability index) in thoracic surgery

The Effects of Intraoperative Fluid Management on Hemodynamics and Tissue Oxygenation According to PVI (Pleth Variability Index) in Thoracic Surgery Aim: Fluid management in thoracic surgery is important in terms of morbidity and mortality. Insufficient fluid replacement can adversely affect many systems, especially hemodynamics. Beside of that, excessive fluid therapy can cause adverse effects on mainly in the lung and many other systems. PVI monitoring, which is noninvasive, easy to use and interpretable, a new and dynamic method for monitoring intravascular fluid volume. In this study, the effects of PVI and traditional fluid regimens on hemodynamics and tissue oxygenation were investigated with PVI in patients who underwent thoracotomy. Materials and Methods: After receiving ethics committee approval, 80 patients (aged between 18-65 years, ASA I-III) who underwent thoracotomy were included in the study. ECG, invasive arterial monitoring, oxygen saturation, temperature monitoring and PVI monitoring were performed in all patients, and 2 ml/kg/h fluid was administered through with the standard anesthesia tecnique. The patients were divided into two groups as control (Group C) and PVI (Group P). Additional fluid requirement in Group C was made according to hemodynamic data. In group P, 250 ml bolus crystalloid was given when PVI>14. Mean arterial pressure (MAP) was aimed to be above 60 mmHg. In case of below 60 mmHg pressure despite adequate fluid support, positive inotropes initiated as a support. Blood pressure, heart rate, peripheral oxygen saturation, arterial blood gas values and lactate were monitored at 30- minute intervals. All kind of administered fluid, blood products and urine output were recorded. In the postoperative period, the blood tests and arterial blood gas analysis of the patients, who were extubated and taken to the Thoracic Surgery Intensive Care Unit, were examined. Results: There was no significant difference between the demographic data of the patients. Although there was no difference between the total amount of fluid given and other follow-up parameters, saturation and MAP values were higher and creatinine values were lower in the PVI group in the postoperative period. Conclusion: PVI follow-up provides better hemodynamics by allowing patients to be given fluids at the appropriate time and in the required amount. It also prevents lung damage that may occur due to excessive fluid load. Peripheral oxygen saturation, which is an indicator of tissue oxygenation, was better in the PVI group and this outcome can be accepted as a consequence of its positive effects on the lung. Similarly, lower creatinine levels can be considered as a positive effect on renal perfusion. Compared with the traditional fluid method, PVI monitoring may be more essential and may produce significant results, especially in patients with advanced age, high ASA score, and severe comorbidities. Key Words: Thoracotomy, Fluid Management, Pleth Variability Index.