Effect of Different Left Lateral Table Tilt for Elective Cesarean Delivery Under Spinal Anesthesia
Effect of Different Left Lateral Table Tilt for Elective Cesarean Delivery Under Spinal Anesthesia
The recommended position of the mother under caesarean section after spinal anesthesia is 15
 degrees left. However, recent research has challenged the basic principles and practicality
 of the left-turn 15 degree position. Higuchi et al used nuclear magnetic imaging to directly
 prove that in the supine position, the position of the full-left 30 degrees of the full-term
 pregnancy of the full-term pregnancy relieved the inferior vena cava compression and the
 left-angle of 15 degrees did not. Therefore, there are more and more controversies about the
 choice of cesarean section position. This experiment aims to explore effects of different
 positions (15 degrees left, 30 degrees left and supine) for elective cesarean section on
 lumbar anesthesia for fetal acid-base balance and maternal Hemodynamic.
When the pregnant woman in the third trimester is in the supine position, the enlarged uterus
 may oppress the inferior vena cava, thereby reducing the amount of blood and heart output of
 the pregnant woman. This affects the mother mainly, such as dizziness, nausea and vomiting,
 chills, and severe irritability，difficulty breathing or even cardiac arrest, the impact on
 the fetus is mainly the reduction of blood flow in the placenta, affecting the blood exchange
 of the uterus placenta, causing neonatal respiratory distress, acidosis and even death. The
 recommended position of the mother under caesarean section after spinal anesthesia is 15
 degrees left. However, recent research has challenged the basic principles and practicality
 of the left-turn 15 degree position. Higuchi et al used nuclear magnetic imaging to directly
 prove that in the supine position, the position of the full-left 30 degrees of the full-term
 pregnancy of the full-term pregnancy relieved the inferior vena cava compression and the
 left-angle of 15 degrees did not. Therefore, there are more and more controversies about the
 choice of cesarean section position. This experiment aims to explore effects of different
 positions (15 degrees left, 30 degrees left and supine) for elective cesarean section on
 lumbar anesthesia for fetal acid-base balance and maternal Hemodynamic.
Inclusion Criteria:

 -  Singleton pregnancy at term via elective cesarean section

 -  Height from 150 cm to 180 cm

 -  American Society of Anesthesiologists (ASA) grade from I to II grade

 -  BMI（Body Mass Index，mearsured weight divided by height squared）less than 35 kg/m2.

 Exclusion Criteria:

 -  Transverse lie

 -  Fetal macrosomia

 -  Uterine abnormalities (e.g., large fibroids, bicornuate uterus)

 -  Polyhydramnios

 -  Ruptured membranes

 -  Oligohydramnios

 -  Intrauterine growth restriction

 -  Gestational or nongestational hypertension, diabetes, eclampsia

 -  Hypertensive disorder or any condition associated with autonomic neuropathy (e.g.,
 diabetes mellitus for more than 10 yr), with renal failure

 -  Have contraindications for spinal anesthesia（Such as low back infection, spinal
 deformity, etc.）

 -  Participants refused to sign informed consent.