How Many Is Too Many? Using Cognitive Load Theory to Determine the Maximum Safe Number of Inpatient Consultations for Trainees.

Purpose: Cognitive load, specifically extraneous load (EL) reflective of distractions, may provide evidence of a lack of focus, potentially making additional work unsafe. The assessment of trainees performing inpatient consultations provides a helpful model for examining this question. The goal of this study was to provide useful information to clinical and educational leaders to optimize inpatient consultation services and rotations and mitigate potential patient safety risk.

Method: In 2019, using the Consult Cognitive Load instrument, the authors obtained EL data from inpatient consultations performed by internal medicine fellows and psychiatry residents across 5 University of California hospitals. In 2023, the authors constructed a Wright map to compare the participants' EL data with the number of prior initial consultations performed during the shift.

Results: Of 326 trainees contacted, 139 (43%) completed the EL survey items. The Wright map shows that trainees were estimated to agree that interruptions were already distracting at the first consultation of the shift. After 4 consultations, trainees were estimated to strongly agree that interruptions were distracting, and to agree that emotions, extraneous information, and technology were distracting.

Conclusions: The authors propose a quantitative, empirically driven, mean safety limit of 4 new inpatient consultations per shift for trainees to avoid cognitive overload, thereby potentially supporting patient safety. Clinical and educational leaders can adjust this limit to fit the unique needs of their practice setting. A similar approach using cognitive load and item response theory could be used to conduct patient safety research in other domains.