T92. Diversity in clinical practice of “Continuous” intraoperative neurophysiologic monitoring (IONM)

Abstract

Introduction Despite advances in neurophysiologic techniques and increased utilization of IONM across a wide diversity of surgical cases, there remain no formal guidelines or consensus about best practice parameters in the implementation of “continuous” monitoring. As critical IONM changes may occur at any time during a surgical procedure, even during “non-critical” periods, variations in total duration of neuromonitoring as well as frequency of evoked potential (EP) acquisition may adversely impact timely and reliable interpretation and communication of such neurophysiologic changes to the surgical team. It is our goal to evaluate the potential variability of IONM practice in both private and academic settings. Methods A practice survey was administered to attendees of the IONM Special Interest Group sessions at the annual ACNS meetings in 2016 (Part I) and 2017 (Part II). This included multiple choice as well as open-ended questions on topics such as the frequency of somatosensory and transcranial motor evoked potential (SSEP and tcMEP) acquisition in the OR, appropriate “start” and “end” times of neuromonitoring, effective communication between the IONM and surgical teams, as well as the number of simultaneous cases that are confidently monitored, and issues related to job satisfaction. These findings are summarized here. Results A total of 35 surveys were returned in 2016 and 30 surveys in 2017, respondents comprising IONM providers in academic, private, and mixed practices. The most popular answer for frequency of SSEP acquisition was every 3–5 min (48%), followed by every 5–7 min (23%). Most common responses regarding frequency of tcMEP acquisition were every 10–15 min (43%) followed by every 5–7 min (25%). Regarding the appropriate duration of an incision/exposure break, answers were especially variable, ranging from zero, to however long it takes to complete exposure (even if that exceeds 30 min). When asked about the maximum number of cases that are simultaneously monitored, responses also varied widely, ranging from 1 to 10 or more. For the question asking how many cases IONM providers felt comfortable monitoring simultaneously, the most common responses ranged from 1 to 6. The most frequent answer to the question of how many cases respondents felt confident monitoring simultaneously was 3 cases or less. A majority of respondents reported satisfaction most of the time with their current practice of IONM. Conclusion There is significant diversity in the clinical practice of IONM, including the frequency of evoked potential acquisition, duration of “continuous” neuromonitoring for a given procedure, and number of simultaneous cases monitored. By highlighting this variability across IONM providers, we are better able to evaluate clinical areas where future improvements and development of emerging practice parameters may be considered that have the potential to positively impact perioperative care and improve patient outcomes.