Apparent acquired resistance to local anesthetics in a pregnant patient: Coincidence or a novel entity?—A Case report

We present a case of a 28-year-old pregnant patient in labor with two prior cesarean sections with a history of both successful and failed spinal anesthesia in her first and second pregnancies, respectively. This time, attempts at spinal anesthesia failed twice despite ruling out the common causes such as technical or drug error. Surgery was ultimately performed under general anesthesia uneventfully. While technical factors may contribute substantially to failure of spinal anesthesia, the sequence of events in this case, viz. one successful subarachnoid block followed by two unsuccessful ones three and seven years apart, supported by investigative evidence, indicates a possible acquired resistance to local anesthetics.