In April 2004, Lorenzo Sanchez underwent knee surgery performed by orthopaedic surgeon, Dr. James Levi. Dr. Daniel Hughes administered anesthesia during the operation. Following the surgery, Sanchez had severe and permanent nerve damage in his leg. Plaintiff filed suit for medical malpractice against Levi, Tucson Orthopaedic Institute, Hughes and Old Pueblo Anesthesiology, relying on the doctrine of res ipsa loquitor. After Sanchez provided an affidavit of an orthopaedic surgeon but not an anesthesiologist, Old Pueblo Anesthesiology moved to dismiss the complaint on the grounds that under A.R.S. § 12-2603(B), the orthopaedic surgeon was not qualified to provide expert testimony against Dr. Hughes. The trial court granted the motion. Tucson Orthopaedic also moved for summary judgment on the grounds that Sanchez failed to establish their case of medical malpractice because res ipsa loquitor was inapplicable and the exert affidavit filed by Sanchez did not meet the requirements of A.R.S. § 12-2603(B). The trial court granted this motion as well, finding that Sanchez had not proven how Levi’s conduct fell below the standard of care or how it caused Sanchez’s injuries. Sanchez appealed both decisions separately. On appeal, Sanchez argued that the trial court erred by finding that A.R.S. § 12-2603 abolishes the doctrine of res ipsa loquitor.
The Arizona Appeal Court affirmed the trial court’s ruling, reasoning that because Sanchez did not establish the elements of res ipsa loquitor, it need not address whether § 12-2603 operates to abolish the doctrine in medical malpractices cases. The Court ruled that because Sanchez alleged that the administration of anesthesiology alone could have caused the injury and did not offer any evidence to show that it was more probable than not that the orthopaedic surgeon had simultaneous control of the injury-causing instrumentality, Sanchez failed to show that Levi had exclusive control of the instrumentality that caused his injury. In a res ipsa loquitor case, the plaintiff is not required to exclude all other possible causes of the injury, but must show that the defendant’s negligence was the most probable cause. The Court explained that this case differs from one involving multiple defendants where it is clear that both were in control of the injury-causing instrument at the time of negligence – in this circumstance, an inference can be made that one or both had caused the plaintiff’s harm. Because Sanchez could not identify the instrumentality that caused the injury, he could not determine which of the two doctors acted negligently.
Judge Eckerstrom authored the opinion, Judges Espinosa and Vásquez concurred.
 The appeal regarding the claims against Old Pueblo Anesthesiology was addressed in a prior opinion by the Arizona Appeals Court, Sanchez v. Old Pueblo Anesthesia, P.C., 218 Ariz. 317, 183 P.3d 1285 (App. 2008).