Preoperative Testing & Laboratory is a diagnostic laboratory that offers many services, including clinical laboratory services, pathology laboratory services, and blood tests. Visit Preoperative Testing & Laboratory located at 525 E Plaza Dr, Santa Maria, CA. This Santa Maria diagnostic laboratory is one of the best in California. As part of the Dignity Health network, Preoperative Testing & Laboratory is dedicated to delivering high quality, compassionate care and access to Santa Maria and nearby communities.