I read with interest the study by Ngan Kee et al.  1They found that a combination of high-dose phenylephrine infusion and rapid crystalloid cohydration virtually eliminated hypotension in women undergoing cesarean delivery during spinal anesthesia. Preventing or treating hypotension in the parturient after spinal anesthesia for cesarean delivery has been the subject of numerous of studies and, as the authors noted, has been referred to as the “Holy Grail” of obstetric anesthesia.2However, the incidence of major complications from hypotension, such as myocardial infarction or stroke to the mother, or neonatal acidosis or low Apgar scores in the baby is almost nonexistent.2,3The most common complications from hypotension are nausea and vomiting, which may be disturbing but are not dangerous.4Furthermore, treating hypotension when it does occur is straightforward; it almost always responds to relatively small boluses of either ephedrine or phenylephrine.

I contend that using a phenylephrine infusion to prevent hypotension during routine cesarean delivery is too aggressive and not safe, as the authors suggest.1A phenylephrine infusion is not benign. Phenylephrine is a potent vasoconstrictor that can cause reactive hypertension and reflex bradycardia. Indeed, close to 50% of the patients in this study developed hypertension from the phenylephrine. Furthermore, to safely use a phenylephrine infusion, especially in high doses as used in this study, the patient should have an indwelling arterial line for continuous blood pressure monitoring. This monitor would be otherwise unnecessary in a healthy parturient. Assessing blood pressure even every minute by an automated blood pressure cuff is simply not sufficient and impractical. Studies to prevent hypotension in parturients are important, but this regimen seems to have risks that outweigh its benefits. The treatment should not be worse than the disease.

Mount Sinai School of Medicine of New York University, New York, New York. yaakov.beilin@mountsinai.org

Ngan Kee WD, Khaw KS, Ng FF: Prevention of hypotension during spinal anesthesia for cesarean delivery. Anesthesiology 2005; 103:744–50
Macarthur A: Solving the problem of spinal-induced hypotension in obstetric anesthesia. Can J Anaesth 2002; 49:536–9
Desalu I, Kushimo OT: Is ephedrine infusion more effective at preventing hypotension than traditional prehydration during spinal anaesthesia for caesarean section in African parturients? Int J Obstet Anesth 2005; 14:294–9
Juhani TP, Hannele H: Complications during spinal anesthesia for cesarean delivery: A clinical report of one year's experience. Reg Anesth 1993; 18:128–31