Anesthesia for cesarean section requires special importance because it may affect both mother
and the baby. To avoid maternal hypotension related to spinal anesthesia must be the primary
objective during anesthesia. Even though many factors influence sensory nerve block for
surgical anesthesia, local anesthetic dose is the main determinant. Another factor that
influence the sensory nerve block is the obesity related to pregnancy. Due to the enlargement
of epidural venous plexus related to pregnancy, the subarachnoid and epidural space reduces,
so the local anesthetic requirement also reduces. Many investigators recommend lower dose of
local anesthetic in obese patients due to reduced requirement There are many studies about
dose regimens for cesarean anesthesia, but ideal dose have not been found. Investigators have
designed this study to see the effects of conventional dose (10 mg bupivacaine) vs. low dose
plus fentanyl (7,5 mg bupivacaine+25 mcg fentanyl) in obese and normal weight pregnant for
cesarean section. The hypothesis was: the low dose regimen provides surgical anesthesia in
obese patients while avoiding maternal hypotension.