Background: Many attempts have been made to look for predictors of hypotension during spinal anaesthesia. Perfusion index (PI) obtained from pulse oximeter has been recently come into focus as predictor of hypotension during spinal anaesthesia for lower segment caesarean section (LSCS).

Aims and Objectives: To estimate the correlation between baseline perfusion index and incidence of hypotension following sub arachnoid block in LSCS.

Materials and Methods: In this prospective observational study, thirty parturients belonging to American society of Anesthesiologists (ASA) physical status 1 or 2 with uncomplicated pregnancies scheduled for elective caesarean section under spinal anaesthesia were included in the study. Spinal anaesthesia was performed with 2ml of 0.5% bupivacaine (hyperbaric) at L3-L4 or L2-L3 interspinous space using a 25G Quincke needle. Hypotension is defined as a decrease in systolic blood pressure (SBP) > 25% from baseline.

Results: The incidence of hypotension among study subjects was 66.7% There was significant correlation between baseline PI and fall in SAP from baseline (r= 0.368, P < 0.05).The optimal cutoff point across a range of cutoff points for PI was found to be 3.6 with a sensitivity of 80% and specificity of 60%,

Conclusion: Baseline perfusion index >3.6 is associated with a higher incidence of hypotension following spinal anaesthesia in elective LSCS.

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Dr Sebastian S Valiaveedan

Department of Anaesthesiology and critical care, Jubilee Mission Medical College and Research Institute Thrissur, Kerala, India

Mobile number-9544361422, Email: This email address is being protected from spambots. You need JavaScript enabled to view it.