Prediction of hypotension during the alveolar recruitment maneuver in spine surgery: A prospective observational study

Abstract

Abstract Background: Atelectasis can occur in many clinical practices. One way to prevent this complication is through the alveolar recruitment maneuver (ARM). However, hemodynamic compromise can accompany ARM. This study aims to reduce the hemodynamic effect of ARM by predicting hypotension during ARM using a non-invasive method. Methods: 94 American Society of Anesthesiologists (ASA) physical status I-II patients aged 19 to 75 with scheduled surgery were enrolled. After anesthesia, we performed a stepwise ARM by MAQUET Flow I. Data on the mean blood pressure (MBP), heart rate, pleth variability index (PVI) and perfusion index (Pi), cardiac index (CI), and stroke volume variation (SVV) were collected before induction of anesthesia (T0), just before ARM (T1), at the start of ARM(T2), 0.5 min(T3), 1 min (T4), 1.5 min (T5, end of ARM), and 2 min after the beginning of ARM (T6). Results: Hypotension was defined as when the MBP at T5 decreased by 20% or more compared to the baseline mean blood pressure; 75 patients developed hypotension during ARM. Pi was considerably higher in the hypotension group than the non-hypotension group before induction. The area under the receiver operating characteristic curve of Pi for predicting hypotension during ARM was 0.718 (95% CI 0.615~0.806; p=0.004), and the threshold value of the Pi was 2.4. Conclusion: A Higher Perfusion index value before induction of anesthesia can be used to predict the development of hypotension during ARM. Prophylactic management of the following hypotension during ARM could be considered in high baseline Pi patients.