Innovations in materials and techniques for spinal anesthesia make it an appropriate choice for many ambulatory surgical procedures and for more traditional inpatient uses. The technique is easily and safely performed in either the lateral, sitting, or jackknife positions with a variety of agent preparations tailored to the surgical requirements. Sedation is often provided to minimize patient anxiety both preoperatively and intraoperatively, usually to the satisfaction of patients who expected to “go to sleep” for their operation. New needle technologies have made postdural puncture headache uncommon (1%). Given the increased risk of epidural hematoma, anticoagulated patients need special consideration in light of new therapies and indications.

The dermatomal distribution of spinal anesthesia can be targeted to a specific patient population and procedure, although interindividual variability limits predictability. Continuous spinal anesthesia may be preferable in some cases. For ambulatory patients, factors that encourage early voiding will minimize time to home readiness. Lidocaine has the optimal onset and duration profile for most outpatient anesthesia; however, transient neurologic symptoms (TNS) occurring after lidocaine spinal anesthesia have recently been documented in a number of prospective studies and epidemiologic reports. TNS can be markedly uncomfortable and occur in approximately 20% of outpatients receiving lidocaine, the group most at risk. Mepivacaine does not appear to offer any advantage over lidocaine, whereas procaine may cause a lower incidence of TNS. Bupivacaine has the lowest associated incidence of TNS and has been adapted for ambulatory surgery using small doses in the 5 to 10 mg range. Ropivacaine resembles bupivacaine for spinal anesthesia with an equipotency ratio of 2:1. Intrathecal adjuncts, such as fentanyl, can improve the success rate of small-dose local anesthetics without prolonging discharge time, making spinal anesthesia more suitable for the growing trend toward outpatient surgery.