Time-Out and Its Role in Neurosurgery

A Prospective Look at the Prevalence of Setup Electrode-Swap Errors Across Over 450 Intraoperative Neuromonitoring Cases

Intraoperative neurophysiological monitoring (IONM) is shown to be useful in surgeries when the nervous system is at risk. Its success in part relies upon proper setup of often dozens of electrodes correctly placed and secured upon patients and inserted in specific stimulating and recording receptacles. Given the complicated setups and the demanding operating room environment, errors in setup are bound to occur. These have led to false negatives associated with new patient morbidities including, at times, paralysis. No studies quantify the prevalence of these types of setup errors. Approximately 800,000 operations annually utilize intraoperative neuromonitoring in the US alone, so even a small percentage of errors suggests clinical significance. In addition, these types of errors hinder the overall effectiveness of IONM and may result in lower reported sensitivities and lower cost-effectiveness of this important service. We sought to discover through a prospective study and verification through chart review the prevalence of "electrode-swap" errors (when recording and/or stimulating electrodes are incorrectly placed on the patient or in the IONM equipment during setup) across all procedures monitored. We found recording and/or stimulating electrode set up errors in 24 of 454 cases (5.3%). These data and examples of how errors were discovered intraoperatively are reported. We also offer techniques to help reduce this error rate. This study demonstrates a significant potential avoidable error in IONM diagnostic utility, patient outcome, and sensitivity/specificity of alert criteria. The value of identifying and correcting these errors is consequential, multifaceted, and far-reaching.

Study design methodology in neurosurgical research

Background

Medical research has evolved from individual expert-described opinions and techniques to scientifically designed methodology-based studies. There are different study designs, and selecting an appropriate study design is critical to appropriately answer the research question being investigated.

Main body

A research question may be addressed using different approaches that can be descriptive, analytical, or experimental. The choice of study design is influenced by features as that related to exposure (intervention) and disease (outcome); considerations related to time, resources, ethics and gaps in scientific knowledge that remain to be filled. The purpose of this review is to provide an overview of the basic study designs as it is the foundation of neurosurgical research to provide valid scientific evidence.

Conclusion

Quality in scientific research begins with a clear hypothesis and a well-formulated design. This entails a thorough understanding of the different study designs to choose the best suited to answer the investigated research question.