Patient safety topics were among the scientific presentations at the Annual Meeting of the International Anesthesia Research Society March 12-16 in Los Angeles.
Dr. D. Bacon and colleagues from Buffalo considered contributing factors to serious adverse surgical and anesthetic outcomes using the ORYX system for evaluation of performance measures promoted by the JCAHO. Overall surgical morbidity was 0.85% and overall surgical mortality (including the first two postop days) was 0.52%. Among the factors statistically associated with serious adverse outcomes were: greater number of preexisting comorbidities, ASA Class 3 or higher, preop nitrates, invasive monitoring, and longer duration of anesthesia.
The practice of extubating adult patients while still “deep” under anesthesia at the end of a surgical case was surveyed by Dr. M. Daley of Baylor. 80% of respondents employ the practice sometimes and 24-43% of respondents do so more than 50% of the time. Concerns about laryngospasm and aspiration were prominently mentioned by respondents who do not use the practice. Prospective randomized studies on the risk:benefit ratio of deep extubation are planned.
Carbon monoxide production by dry CO2 absorbant reacting with isoflurane was reduced by more than a third with the use of a potassium hydroxide-free “soda lime” absorbant, reported Drs. E. Knoell and H. Gilly of Vienna, Austria.
The risk of adverse cardiac outcome following liver transplantation was studied by Dr. G. Neelakanta and associates from UCLA. In 359 patients, there were four MIs and three cardiac deaths. Use of preop stress echo is to be studied further.
Dr. S. Parnass et al. of Rush Medical College did a survey on practices regarding postop pain management epidural catheters in patients receiving antithrombosis therapy with low molecular weight heparin. There was a fairly even split between the pro and con camps. Departments using epidurals had rules and protocols for timing of catheter removal and heparin dosing.
Video Studies
Finally, Dr. V. Wertheim and associates from UC San Diego studied the validity of using videotapes of OR cases to evaluate anesthetists’ performance by comparing ratings of tapes (“off line”) with similar ratings made live (“real time”) in the actual OR during the anesthetic. There was strong intra-observer reproducibility and strong agreement between real time and off line analyses of the same anesthetics. Demonstrating the utility of using videotapes of anesthetic cases to study human factors and human performance “will provide a rational basis for the study of training strategies, work schedules, and anesthesia devices, hopefully leading to enhanced safety.”
These brief descriptions only highlight the IARS presentations. Readers with further interest are referred to S150-S172 in the February, 1999 (Vol. 88, No. 2S), supplement to Anesthesia and Analgesia.