To compare two infusion rates of norepinephrine for prophylaxis against post-spinal hypotension during caesarean delivery.

Hypotension after spinal anesthesia for cesarean delivery is common and is caused mainly by peripheral vasodilatation. Although the intravenous administration of fluids helps, it does not always prevent maternal hypotension. Usually, this hypotension is treated with phenylephrine or ephedrine.

Norepinephrine has been recently introduced for prophylaxis against post-spinal hypotension during cesarean delivery due to its α-adrenergic activity in addition to the weak β-adrenergic activity.

Although the use of norepinephrine for this purpose has shown promising results. However, no sufficient data are available with regard to its optimum dose.

The objective of this study is to compare two infusion rates of norepinephrine for prophylaxis against post-spinal hypotension during caesarean delivery.

Inclusion Criteria:

• Pregnant women scheduled for cesarean section under spinal anesthesia
• Gestational age of at least 37 weeks

Exclusion Criteria:

• Patient refusal
• Contraindications of spinal anesthesia
• Allergy to the study drug
• Height<150 cm, weight < 60 kg, body mass index (BMI) ≥40 kg/m2.
• patients with cardiac morbidities
• Hypertensive disorders of pregnancy.
• Prepartum hemorrhage