Perfusion index as a predictor of hypotension following subarachnoid block in parturients with non-severe pre-eclampsia undergoing lower segment cesarean section

Abstract

Background and Aims: Perfusion index, which assesses perfusion dynamics is used as a non‑invasive method in spinal anesthesia cases to detect the occurrence of hypotension. A Perfusion Index value after which hypotension is common can be assessed. Methods: In this prospective double-blind observational study, 100 parturients were included. Baseline Perfusion Index was recorded and spinal anesthesia was carried out with Injection bupivacaine 0.5% (hyperbaric), 10 mg at L3 - L4 / L2 - L3 intervertebral space. Fall in Systolic Blood Pressure < 20 % of baseline was defined as hypotension. Chi-Square test and independent sample t-test was used for the statistical analysis. Spearman’s rank correlation coefficient was applied to assess the correlation between baseline PI and hypotension. The receiver operating characteristic (ROC) curve was mapped for PI and the occurrence of hypotension. Results: The occurrence of hypotension in parturients with PI < 4.25 was 40.9% compared to 94.6% in parturients with PI > 4.25. There was a remarkable association between baseline PI > 4.25, the number of episodes of hypotension 53/100 (p-value < 0.0001) and the total dose of phenylephrine used 53/100 (p-value 0.02). T