Phenylephrine has become the favoured agent for hypotension during spinal anesthesia for Cesarean and studies show that using a continuous prophylactic infusion works best and also lowers nausea and vomiting. link
Norepinephrine is a similarly acting agent and studies are appearing showing its utility in preventing hypotension. “A manually titrated infusion of 5 µg/mL of norepinephrine was effective for maintaining BP and decreasing the incidence of hypotension, with no detectable detrimental effect on neonatal outcome”.
Some dose ideas are present in this study. But it may take time and more studies to be adopted by anesthesiologists more familiar with its ICU use, as well as direct comparison with current agents.