This study aims to distinguish between premixed, sequential, and manually mixed administration of intrathecal fentanyl and bupivacaine in cesarean section.

Cesarean section (CS) is a lifesaving procedure when there is both maternal and fetal problems. The rate of CS increases dramatically from time to time. Regional anesthesia techniques are highly preferred for CS compared to general anesthesia.

Coadministration of intrathecal opioids and local anesthetics (LAs) have been found to produce a potent intra and postoperative analgesic synergism without further depression of efferent sympathetic activity, hence results in less adverse hemodynamic effects, even with sub-therapeutic doses of LAs.

Fentanyl has been considered the intrathecal LAs adjuvant of choice owing to its potency, fast onset and short duration of action, and lower incidence of respiratory depression.

Inclusion Criteria:

• Age from 18 to 40 years.
• Height between 150 to175 cm.
• Body mass index (BMI) between 18.5 and 30 kg/m2.
• American Society of Anesthesiology (ASA) physical status II.
• Scheduled for cesarean section under spinal anesthesia.

Exclusion Criteria:

• Pre-operation hypotension and bradycardia.
• Preeclampsia.
• Multiple pregnancy and macrosomia.
• Complete or partial failed spinal.
• Patients with skin infections at the site of injection.
• Patients with coagulation disorders.
• Patients with spinal deformities.
• Patients having regional nerve block other than spinal anesthesia.

Women undergoing cesarean section

The data will be available upon a reasonable request from the corresponding author after the end of study for one year.

After the end of study for one year.

The data will be available upon a reasonable request from the corresponding author.