Surgical times components; induction of regional anesthesia till delivery (I-D interval); incision of the skin till delivery (S-D interval); and incision of the uterus till delivery (U-D interval)) were recorded using a stopwatch.
Immediately after delivery, umbilical cords were clamped on both ends and an arterial blood sample was collected anaerobically in a pre-heparinized insulin syringe. PH, base excess (BE), carbon dioxide pressure (PCO2), Oxygen pressure (PO2) and Bicarbonate (HCO3) levels were measured at 37oC by pH and gas analyzer (Gem, Premier3000, USA). The gas analysis was done in less than 30 minutes after sampling.
Apgar score was assessed by a neonatologist at the 1st and 5th minutes after birth . Advanced resuscitation included positive pressure ventilation, chest compression and/or drugs administration. All resuscitated babies were transferred to neonatal intensive care unit for post resuscitation care. Fetal distress was defined by an umbilical cord pH \<7.12
