As any anesthetist or anesthesiologist knows, there is always a risk of complications when a patient is put under general anesthesia. This risk became reality when Dr. Giorgio Ionnelli’s dog died while undergoing an experimental cardiac surgical procedure. The veterinary technician administering and monitoring the isoflurane anesthesia tried, but she was unable to revive and save the animal when its blood pressure dropped acutely, and the animal went into cardiac arrest.

Ionnelli voluntarily halted his study until the school’s veterinarians and the IACUC could investigate the incident. After a thorough review, the investigators reported that they found no problems with the surgeon’s performance, the technician’s efforts to revive the dog, or the readouts from the blood pressure and electrocardiographic monitors. They suspected that the anesthetic vaporizer, which had been serviced recently, was providing an excessive amount of isoflurane gas at each setting of the machine. This suspicion was confirmed after an inspection by another technician from the company that had serviced the vaporizer. The machine was repaired and recalibrated, but the IACUC was faced with the question of what to report to the federal government, if anything. Some IACUC members and Ionnelli believed this was a single instance of a mechanical failure and not noncompliance with the PHS Policy1 or the Guide2. However, the chairman of the IACUC said that because Ionnelli voluntarily halted his study, and the IACUC did not disagree with that action, the stoppage was analogous to a suspension by the IACUC and it had to be reported as such to OLAW and the USDA. The veterinarians were unsure of what advice to give to the IACUC. Although Ionnelli’s IACUC-approved protocol clearly stated that after induction, anesthesia would be maintained at three percent isoflurane, and that was what was recorded on the anesthesia monitoring sheet, they knew that the numbers on the vaporizer showing the percent of isoflurane being delivered were not meant to be taken as the standard for judging the depth of anesthesia. Rather, they believed it was the job of the person monitoring the animal to adjust the anesthetic depth as needed.

What should the veterinarians tell the IACUC? What, if anything, should the IACUC report to OLAW and the USDA? Is there anything that might be done to help prevent a repeat of this problem?