Ultrasound and Neuraxial Anesthesia in Pregnancy

Ultrasonography is routinely performed during pregnancy by obstetricians to visualize the fetus, making patients familiar and comfortable with its usage. Ultrasonography does not result in adverse effects to the mother or fetus and is readily available at most facilities, yet is not routinely used to identify lumbar interspaces prior to providing neuraxial anesthesia. Ultrasonography is a valuable tool for accurately identifying lumbar intervertebral spaces and is more accurate than simple palpation of obscure anatomic landmarks. The investigators are interested to know the accuracy of anatomic landmark palpation in predicting the lumbar interspace of neuraxial anesthesia administration compared to identification of the interspace by ultrasound. The investigators are also interested in presenting anesthesia providers with feedback regarding their accuracy and then investigating whether this feedback causes a change in provider practice (i.e. use of ultrasound) or improved identification of the interspace prior to providing neuraxial anesthesia.