Closed claims studies in anesthesia: a literature review and implications for practice.

Historically, closed malpractice claims have been used to identify and examine potential causes for adverse anesthesia outcomes. In the United States, the American Association of Nurse Anesthetists and the American Society of Anesthesiologists have compiled and analyzed such data. In all claims filed, respiratory events were most common, and the most common outcome class was brain damage or death. These findings and others led to improved practice standards, including end-tidal carbon dioxide and pulse oximetry monitoring. Although some researchers have cited closed claims studies as evidence of anesthesia risk trends, the nature of the data makes it inappropriate for calculation or comparison of risk. Further work is needed to elucidate some mechanisms of injury and to develop interventions to maximize patient safety.