P had a lumbar laminectomy with spinal fusion on June 17, 2003, at D's Medical Center. P filed suit alleging that she was infected by Escherichia coli bacteria (more commonly referred to as E. coli) during the surgery. In their third amended petition, P alleged a res ipsa loquitur theory against Ds on the basis that an infection in the surgical site itself does not occur in the absence of negligence. P alleged that all of the equipment and materials used in the surgery were prepared by D and P was unconscious due to anesthesia given to her at the time of the surgery, that her body and the surgical site were under the exclusive and joint control of Ds, and that Ds had greater knowledge of the possible causes of the infection. Ds moved to dismiss. P conceded that they could not prove the specific way in which the negligence occurred, but urged that they should be able to rely on expert testimony in support of the theory of res ipsa loquitur to show that Ds were negligent. The trial court dismissed the suit with prejudice. This appeal resulted.