Perfusion index in the follow-up of postoperative pain: hypertensive patient sample

Background: The relative changes in perfusion index following postoperative analgesia were investigated. The study also aimed to investigate the ability of perfusion index to predict analgesic requirements. As a secondary aim, the results of the relative changes in perfusion index in individuals with hypertension were analyzed. Methods: A total of 100 patients with American Society of Anesthesiologists (ASA) 1-3 with or without hypertension who were scheduled to undergo open abdominal surgery between 01 April 2023 and 30 November 2023 were included in the study. The relative variability of visual analogue scale and perfusion index in patients receiving postoperative analgesia was examined. We also studied at which these variables predicted postoperative pain following rescue analgesia. The patients with hypertension were analysed alongside other patient groups. Results: The relative change in perfusion index was found to have a higher ability to predict the need for analgesia in patients with high postoperative Visuel Analogue Scale (VAS) scores. This ability was found to be increased in patients with hypertension. The number of patients with moderate to high pain (VAS >6) in the postoperative period was found to be 86. Conclusions: The area under the Receiver Operating Characteristic (ROC) curve was found to have a sensitivity of 64% with a positive predictive value of 86%. Therefore relative changes in perfusion index can be used as a method to predict postoperative pain. Clinical Trial Registration: Protocol ID: 76988455-050, Identification No NCT06535581.