Classification of A Nonroutine Surgical Event

By January 10, 2021Uncategorized

Despite efforts to improve perioperative patient safety over the past two decades, medical errors remain a significant cause of morbidity and mortality [1]. Safety improvement research has long been hindered by the weak relationship between healthcare interventions and adverse outcomes like morbidity and mortality [2]. These outcomes are rare in clinical research, limiting statistical power to demonstrate associations [2]. As a result, traditional methods of measuring morbidity and mortality have indicated inconsistent relationships with healthcare interventions [2]. Recently, an alternative to rare outcome measures, known as the “nonroutine event,” has been proposed [2]. 

A nonroutine event is defined as any aspect of clinical care perceived by clinicians or observers as a deviation from optimal care for a patient in a specific clinical scenario [3]. The concept of a nonroutine event includes not only the occurrence or near-occurrence of patient injury but also flawed care processes such as missing or broken equipment, delayed lab tests, insufficient training, and interpersonal communication errors [4,5]. It encompasses incidents that may not be directly linked to patient injury, which previously have been unreliably documented by reporting systems [4]. The nonroutine event reporting system is modeled after safety processes in the nuclear power industry where any deviation from optimal operating procedures is reported and investigated [4]. The foundation of this safety concept is represented by the principle of the “accident triangle” that relates frequent, low-importance events to infrequent, high-importance events such as morbidity and mortality [4]. 

The nonroutine event concept is broader than previous measurements used to assess clinical performance and medical error [2]. Because most nonroutine events do not involve errors by the care provider and few lead to patient injury, nonroutine events allow researchers to study underlying system processes without the negative implications of medical error [2,5].  

Initially, nonroutine events were used to retrospectively analyze workflow disruptions in anesthesia teams [5]. A 2002 study completed by researchers affiliated with the University of California, San Diego investigated the prevalence of nonroutine events in anesthesia care [6]. Anesthesiologists spend roughly 45% of the initial set-up time at the start of a normal workday on drug and fluid tasks, such as obtaining and filling syringes [6]. In observing anesthesiologists complete 68 drug and fluidrelated tasks, the researchers noted several nonroutine events including: difficulty finding anesthesia supplies, providers bumping into or tripping over IV poles or lines, malfunctioning infusion pumps, and blood leaking from IVs [6]. The results of the study suggested that many anesthesia drug and fluid tasks are inefficient, which may promote medical error [6]. 

The observed high incidence of nonroutine events has made it possible to collect prospective data to improve safety systems [6]. Today, nonroutine events are also used to assess the workflow of various surgical teams and team performance in the operating room [5]. A 2019 study completed at Children’s National Hospital in Washington, D.C. investigated the incidence of nonroutine events during pediatric trauma resuscitation [1]. The researchers reviewed 39 resuscitations and identified 337 nonroutine events [1]. The most frequent nonroutine event was failure to stabilize the cervical spine [1]. The results of the study highlighted common errors during pediatric trauma resuscitation that may lead to adverse outcomes [1]. 

Medical errors compromising patient safety and resulting in patient harm remain a significant health burden [1]. The nonroutine event concept provides a system to collect detailed information about types of deviations from optimal care and to show associations with long-term patient outcomes [4]. 




  1. Webman, R., Fritzeen, J., Yang, J., Ye, G., Mullan, P., & Qureshi, F. et al. (2016). Classification and team response to nonroutine events occurring during pediatric trauma resuscitation. Journal of Trauma and Acute Care Surgery, 81(4), 666-673. doi:10.1097/ta.0000000000001196 
  1. Lane-Fall, M., & Bass, E. (2020). “Nonroutine Events” as a Nonroutine Outcome for Perioperative Systems Research. Anesthesiology, 133(1), 8-10. doi:10.1097/aln.0000000000003125 
  1. Wacker, J. (2010). Managing Non-Routine Events in Anesthesia–A Concept to Measure and Improve Anesthesia Quality. Human Factors, 52(2):282-294. doi:10.1177/0018720809359178 
  1. Liberman, J., Slagle, J., Whitney, G., Shotwell, M., Lorinc, A., Porterfield, E., & Weinger, M. (2020). Incidence and Classification of Nonroutine Events during Anesthesia Care. Anesthesiology, 133(1), 41-52. doi:10.1097/aln.0000000000003336 
  1. Law, K. E., Hildebrand, E. A., Hawthorne, H. J., Hallbeck, M. S., Branaghan, R. J., Dowdy, S. C., & Blocker, R. C. (2019). A pilot study of non-routine events in gynecological surgery: Type, impact, and effect. Gynecologic Oncology, 152(2), 298-303. doi:10.1016/j.ygyno.2018.11.035 
  1. Weinger, M. (2002). Human Factors Research in Anesthesia Patient Safety: Techniques to Elucidate Factors Affecting Clinical Task Performance and Decision Making. Journal of The American Medical Informatics Association, 9(90061), 58S-63. doi:10.1197/jamia.m1229