Prediction of post-induction hypotension by point-of-care echocardiography: A prospective observational study

Background: Post-induction hypotension (PIH) is a common side effect of general anaesthesia and is associated with poor perioperative outcomes. We assessed the ability of two point-of-care echocardiographic variables to predict the occurrence of PIH: the passive leg raising-induced changes in the velocity-time integral of the left ventricular outflow tract (Delta VTI-PLR) and the inferior vena cava collapsibility index (IVC-CI). Methods: We studied 64 patients > 50 years scheduled for elective abdominal surgery. Delta VTI-PLR and IVC-CI were prospectively obtained before general anaesthesia induction. PIH was defined by a systolic arterial pressure < 90 mmHg or a mean arterial pressure < 65 mmHg or by a decrease in systolic or mean arterial pressure > 30% from pre-induction level. Intraclass correlation coefficients (ICCs) were calculated to assess the reproducibility of echocardiographic measurements. Receiver operating characteristic (ROC) curves with 95% confidence intervals (Cls) were generated to test the ability of Delta VTI-PLR and IVC-CI to predict the occurrence of PIH. Results: PIH occurred in 33 (51%) patients. The ICCs for VTI and IVC measurements showed excellent reproducibility. The occurrence of PIH was accurately predicted by Delta VTI-PLR with an area under the ROC curve (AUROC) of 0.89 (95% CI: 0.80-0.97), a threshold value of 18% with a sensitivity of 88% (95% CI: 71-97%) and a specificity of 84% (95% CI: 66-94%). The occurrence of PIH was poorly predicted by IVC-CI with an AUROC of 0.68 (95% CI: 0.54-0.80) and a threshold value of 42%. Conclusions: Delta VTI-PLR, unlike IVC-CI, could reliably predict the occurrence of PIH. The use of Delta VTI-PLR could help individualise anaesthesia management to prevent PIH. (C) 2022 Societe francaise d'anesthesie et de reanimation (Sfar). Published by Elsevier Masson SAS. All rights reserved.