What is considered a low platelet count from the perspective of epidural catheter placement?

What is considered a low platelet count from the perspective of epidural catheter placement and why is there controversy regarding choosing a lowest “safe” platelet count?

An epidural hematoma is a catastrophic complication, which can lead to permanent paralysis. It is, therefore, pru-dent to practice in a conservative manner and not place an epidural anesthetic if the patient is at any risk of developing this complication. Cousins and Bromage recommended in 1988 that one should not perform an epidural anesthetic if the platelet count is less than 100,000 mm⁻³. Recently, how-ever, this recommendation has been widely disputed.

Thrombocytopenia is the most common hematologic disorder during pregnancy. Choosing an absolute platelet count below which it is considered too dangerous to place a neuraxial anesthetic may dictate the use of general anes-thesia, a riskier technique in the parturient. Hawkins et al. (1997) reviewed pregnancy-related deaths in the United States between 1985 and 1990 and found that the fatality rate for a parturient administered general anesthesia for cesarean section was 32 deaths per million and for neuraxial anesthesia was only 2 deaths per million.

Refraining from administering a neuraxial anesthetic during the labor and delivery process based on a low platelet count commits the patient, at least, to a painful labor. It is possible that later in the course of labor the woman may require a cesarean delivery, perhaps emergently. The anesthesiologist in that situation may then be forced to administer an anesthetic under less than optimal conditions.