Can Passive Leg Raise Prevent Spinal Anesthesia-induced Hypotension During Cesarean Section?

All over the world, spinal anesthesia is widely used in cesarean sections due to its superiority over general anesthesia. Due to reasons such as increased sensitivity to local anesthetics and increased intra-abdominal pressure in pregnant women, the frequency of hypotension increases by up to 70%. As a result of the blockage of sympathetic vasoconstrictor fibers originating from T1-L2 segments, loss of peripheral resistance, venous ponding occurs, and cardiac output decreases. Also, the level required for cesarean operation is T4 or T5, and the possibility of affecting the cardiac accelerator fibers, so bradycardia due to the increase in parasympathetic activity may deepen the hypotension. If postspinal hypotension is not managed correctly, it may lead to maternal and fetal complications. In addition to classical methods such as fluid loading and prophylactic vasoconstrictor application to prevent hypotension in pregnant women after spinal anesthesia, techniques such as wrapping the lower extremity, lifting, or applying both together have been in question.

Passive leg raise application is an easy method that allows the blood collected in the lower part of the body to participate in the central circulation with the effect of gravity. An increase in venous return occurs with the passage of blood from the lower extremities to the thorax. Thus, it leads to an increase in stroke volume and an increase in cardiac output. In this study, we aimed to determine the effectiveness of passive leg raising in preventing or reducing the depth of hypotension after spinal anesthesia in pregnant women who underwent cesarean section under spinal anesthesia.