Predicting Hypotension after Spinal Anesthesia for Elective Cesarean Delivery Using a Multimodal Ultrasound Approach: A Prospective Observational Study

Background: Spinal anesthesia-induced hypotension (SAIH) is common during cesarean delivery, and clinical predictors perform poorly. Aims and Objective: To evaluate the inferior vena cava collapsibility index (IVCCI), subclavian vein collapsibility index (SCVCI) and left ventricular end-diastolic area (LVEDA), alone and combined, for predicting SAIH. Materials and Methods: This prospective observational study enrolled 100 consecutive term parturients (ASA II) undergoing elective cesarean delivery under spinal anesthesia at a tertiary centre in Jhansi (May 2025–April 2026). IVCCI, SCVCI and LVEDA were measured before the block. SAIH was defined as a systolic blood pressure fall >20% from baseline or <90 mmHg within 30 minutes. Sensitivity, specificity, predictive values and receiver operating characteristic curves were analysed. Results: SAIH occurred in 64 parturients (64%; 95% CI 54.2–72.7). IVCCI values did not overlap between groups (area under the curve [AUC] 1.00, 95% CI 0.96–1.00); at the ≥40% cut-off, sensitivity was 90.6% and specificity 100%. SCVCI ≥21% had a sensitivity of 93.8% and specificity of 61.1% (AUC 0.81); LVEDA did not discriminate (AUC 0.46). A multimodal rule (IVCCI ≥40% or SCVCI ≥21%) increased sensitivity to 98.4% (p=0.06 vs IVCCI alone) and negative predictive value to 95.7%, but reduced specificity (61.1%) and accuracy (85% vs 94%). Hypotensive parturients had a higher baseline heart rate (100.5 vs 85.3 bpm; p<0.001). Conclusion: IVCCI showed excellent apparent discrimination for SAIH in this single-centre cohort. Adding SCVCI increased sensitivity but reduced specificity and accuracy, and LVEDA added no predictive information. These thresholds require independent validation.