Perfusion Index as a Predictor of Hypotension Following Sub-arachnoid Block Among Patients Undergoing Lower Segment Caesarean Section

Spinal anesthesia is employed to provide excellent surgical conditions in case of C-Section. It is the anesthetic technique of choice among obstetric patients. However it is associated with sympathectomy which reduces the venous return and ultimately causes hypotension. This hypotension is mainly due to redistribution of blood volume to the peripheral compartment. Perfusion index which is measured by Pulse Oximetery is a ratio of pulsatile to non-pulsatile blood in the peripheral compartment of the body. As spinal anesthesia causes sympathectomy, peripheral blood volume increases. As a result perfusion index value should rise. This will then co-relate with hypotension. In simple terms those individuals who have a high baseline Perfusion index value will more likely to develop hypotension. This study aims to identify the baseline perfusion index value which co-relates with development of hypotension following sub-arachnoid block for C-section.